JP2015084044A - Light diffusion member and lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light diffusion member and a lighting system capable of diffusing incident light to a wide range.SOLUTION: A light diffusion member 3 includes: a reflection base 31; and a cured product layer 32 having an electron beam curable resin layer or a thermosetting resin layer arranged on the reflection base. A surface of the cured product layer on a side opposite to the reflection base is made into a rough surface. The cured product layer includes a plurality of resin beads 34. The surface of the cured product layer on the side opposite to the reflection base has convexoconcave by the plurality of resin beads arranged in a surface direction.

Description

  The present invention relates to a light diffusing member and a daylighting system.

  Light control sheet that improves daylighting efficiency by reflecting outside light incident on the window toward the indoor ceiling as part of efforts to reduce carbon dioxide emissions and reduce power consumption by reducing the intensity of indoor lighting. Has been proposed. For example, in Patent Document 1, a light control sheet having a structure in which transmissive portions and light-shielding portions are alternately arranged is attached to, for example, a window glass, and sunlight is taken in indoors in summer due to a difference in the incident angle of sunlight. In the winter, the intake of sunlight is increased.

JP 2010-259406 A

  The light taken indoors by the light control sheet is incident on the ceiling or wall surface. Wallpapers are often provided on the ceiling and walls. However, the conventional wallpaper has a total light reflectance as low as 90% or less, and the light incident on the wallpaper cannot be efficiently diffusely reflected indoors. For this reason, even if outside light is taken indoors with the light control sheet, conventionally, the taken light cannot be effectively used for daylighting.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a light diffusing member and a daylighting system capable of diffusing incident light over a wide range.

In order to solve the above problems, in one embodiment of the present invention,
A reflective substrate;
A cured product layer comprising an electron beam curable resin layer or a thermosetting resin layer disposed on the reflective substrate,
A light diffusing member is provided in which a surface of the cured product layer opposite to the reflective substrate is roughened.

  Moreover, the surface on the opposite side to the said reflective base material of the said hardened | cured material layer may be embossed.

  Moreover, the said hardened | cured material layer may contain the some resin bead, and the surface on the opposite side to the said reflective base material of the said hardened | cured material layer is uneven | corrugated by the said some resin bead arrange | positioned in the said surface direction. You may have.

In another aspect of the present invention, a first light control member that reflects incident light in a predetermined direction;
A second light control member for diffusing the light reflected by the first light control member,
The second light control member is
A reflective substrate;
A cured product layer comprising an electron beam curable resin layer or a thermosetting resin layer disposed on the reflective substrate,
There is provided a daylighting system in which a surface of the cured product layer opposite to the reflective base is roughened.

  Incident light incident on the first light control member may be external light, and the second light control member may be disposed on an indoor ceiling surface or wall surface.

  The second light control member may diffuse the light reflected by the first light control member and diffuse the illumination light incident on the second light control member.

  According to the present invention, incident light can be diffused over a wide range.

The figure which shows schematic structure of the lighting system provided with the light-diffusion member which concerns on one Embodiment. Sectional drawing of the light control member 2 laminated | stacked on a window or the lighting tool 4. FIG. The perspective view of the slat 21 of the blind 5. FIG. The main sectional view of slat 21. Sectional drawing of the light-diffusion member 3 by which the unevenness | corrugation was formed in the upper surface of the electron beam cured resin layer or the thermosetting resin layer 32. FIG. Sectional drawing of the light-diffusion member 3 in which the unevenness | corrugation by the resin bead was formed. The figure which shows the experimental result of the experiment 1. FIG. The figure which shows the experimental result of experiment 2

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a diagram showing a schematic configuration of a daylighting system 1 including a light diffusing member according to an embodiment of the present invention. The daylighting system 1 of FIG. 1 includes a light control member (first light control member) 2 and a light diffusion member (second light control member 2) 3.

  The light control member 2 is used by being laminated on, for example, a window or a lighting tool 4, or is incorporated in a blind 5 provided separately from the window or the lighting tool 4 as shown in FIG.

  FIG. 2 is a cross-sectional view of the light control member 2 stacked on the window or the lighting tool 4. The light control member 2 shown in FIG. 2 is disposed under the light control layer 7 disposed on the base material layer 6, the adhesive layer 8 disposed on the light control layer 7, and the base material layer 6. Hard coat layer 9. The light control member 2 can be laminated on the window or the lighting tool 4 through the adhesive layer 8. The light control member 2 may be supported and laminated between a pair of windows. In such a case, the adhesive layer 8 and the base material layer 6 may not be provided. Moreover, the light control member 2 may be integrally formed inside the window or the lighting tool 4.

  The light control layer 7 in FIG. 2 is formed in a base portion 11 in which a plurality of grooves 10 are formed so as to be spaced apart along one surface 7 a thereof, and in the plurality of grooves 10 in the base portion 11. In addition, a plurality of louver portions 12 having optical characteristics different from the base portion 11 are provided. By making the refractive index of the louver part 12 lower than the refractive index of the base part 11, sunlight incident from the window or the daylighting tool 4 is totally reflected at the interface between the base part 11 and the louver part 12, and the indoor ceiling Further, it is possible to provide a light deflection function that guides in the wall direction. Moreover, the light shielding function according to the incident angle of sunlight can also be provided by making the absorptivity and reflectance of ultraviolet light, visible light, infrared light, etc. of the louver part 12 higher than the base part 11. . Furthermore, the directional light emission function can be provided by making the light emission rate of the louver part 12 higher than that of the base part 11.

  In the present embodiment, external light reflected by the light control member 2 is incident on the light diffusion member 3. Therefore, it is desirable to adjust the reflection direction of the light control member 2 in accordance with the location of the light diffusion member 3. The reflection direction of the light control member 2 can be adjusted by adjusting the material and shape of the louver part 12, for example.

  The light control layer 7 may have a structure in which a plurality of prism portions that reflect incident light in a predetermined direction are arranged along the one surface 7a instead of the base portion 11 and the louver portion 12.

  FIG. 3 is a perspective view of one slat 21 constituting the blind 5, and FIG. 4 is a main sectional view of the slat 21. The slat 21 includes a base material layer 22, a light control layer 23 supported on the base material layer 22, and a functional layer (protective layer) 24 disposed on the light control layer 23. The base material layer 22, the light control layer 23, and the functional layer 24 extend along the longitudinal direction of the slat 21.

  The base material layer 22 can be formed of a transparent or translucent resin film. The light control layer 23 includes a base portion 26 formed with a plurality of grooves 25 that are spaced apart along the short direction of the slat 21, and optical characteristics different from the base portion 26 that are formed inside the grooves 25. And a plurality of louver portions 27. Each of the base portion 26 and the plurality of louver portions 27 extends in the longitudinal direction of the slat 21.

  As shown in FIG. 4, the louver part 27 has, for example, two different inclined surfaces, and can reflect light incident on these inclined surfaces in different directions indoors. Note that it is not always necessary to provide two different inclined surfaces in the louver portion 27, and only one inclined surface may be provided to reflect light in a predetermined direction indoors.

  Similar to the louver part 27 and the base part 26 shown in FIG. 2, the louver part 27 and the base part 26 in FIG. 4 are also made of different materials so that the reflection characteristics of the light incident on the louver part 27 can be variously changed. can do.

  The light diffusing member 3 according to the present embodiment is disposed on, for example, an indoor ceiling or a wall surface connected to the ceiling. Although it is not necessary to arrange the light diffusing member 3 on the entire ceiling or wall surface, it is desirable to increase the ground contact area of the light diffusing member 3 if the interior is to be illuminated as brightly as possible.

  The light diffusing member 3 can diffuse not only the external light reflected by the light control member 2 but also the illumination light incident on the light diffusing member 3. That is, the light diffusing member 3 mainly diffuses external light during the daytime and diffuses illumination light at night. Thereby, the daylighting efficiency can be improved and the lighting efficiency can be improved at night. Therefore, the use time of the indoor lighting can be shortened, the illumination intensity of the indoor lighting can be reduced, and power consumption and carbon dioxide emission can be reduced.

  The light diffusing member 3 includes a reflective base material 31 and an electron beam curable resin layer or a thermosetting resin layer 32 disposed on the reflective base material 31 as shown in a detailed cross-sectional view in FIG. The surface of the electron beam curable resin layer or the thermosetting resin layer 32 on the side opposite to the reflective substrate 31 is roughened.

  The reflective base material 31 is preferably formed of a material having excellent reflection performance. For example, a white biaxial film obtained by stretching a PET (polyethylene terephthalate) resin in a biaxial direction after film formation to align molecules and crystallize them. A PET film having a stretched void structure is used. By stretching in the biaxial direction, the strength and heat resistance can be improved.

  The electron beam curable resin layer 32 is a cured product formed by irradiating an electron beam curable resin with an electron beam. The electron beam curable resin is formed using, for example, a polymerizable monomer, a polymerizable oligomer, or a prepolymer as appropriate. For example, a polyfunctional acrylate is used as the polymerizable monomer. Examples of the polymerizable oligomer include epoxy acrylate, urethane acrylate, polyester acrylate, and polyether acrylate.

  The thermosetting resin layer 32 is a cured product formed by applying heat to the thermosetting resin. The thermosetting resin is, for example, a urethane resin or an epoxy resin.

  The electron beam curable resin or thermosetting resin of this embodiment is characterized by excellent durability, weather resistance, and abrasion resistance. In order to further improve durability, weather resistance, and abrasion resistance, various additives may be contained in the electron beam curable resin or the thermosetting resin. For example, in order to further improve the weather resistance, an ultraviolet absorber or a light stabilizer may be added. In addition, since thermosetting resins are generally inferior in abrasion resistance compared to electron beam curable resins, when using thermosetting resins, additives for improving abrasion resistance are included in thermosetting resins. May be.

  In addition, when an electron beam curable resin or a thermosetting resin is applied on the reflective substrate 31, a primer layer (not shown) is provided between the reflective substrate 31 and the electron beam curable resin or the thermosetting resin. You may arrange. The primer layer is for increasing the adhesive force between the reflective substrate 31 and the electron beam curable resin or thermosetting resin, but contains a light stabilizer or the like in the primer layer in order to further improve the weather resistance. You may let them.

  The electron beam curable resin or thermosetting resin of the present embodiment is cured by being irradiated with an electron beam or applied with heat after being applied on the reflective base material 31, or an electron beam curable resin layer or a thermosetting resin. Resin layer 32 is formed. Since the electron beam curable resin layer and the thermosetting resin 32 have a certain degree of softness even after being cured, the upper surface of the electron beam curable resin layer and the thermosetting resin 32 are brought into contact with a mold or the like having irregularities formed thereon to pressurize, as shown in FIG. As described above, the unevenness 33 can be formed on the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32. A known embossing process can be applied to the method for forming the unevenness.

  As described above, by roughening the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32, the light diffusion performance of the electron beam curable resin layer or the thermosetting resin layer 32 can be improved. In order to improve the light diffusion performance, it is desirable that the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32 is randomly inclined in various directions. Therefore, a large number of fine irregularities having various inclination angles may be formed in advance on the surface of the mold, and the irregularities may be transferred to the electron beam curable resin layer or the thermosetting resin layer 32.

  A part of the light incident on the light diffusing member 3 is diffused on the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32. Other light passes through the electron beam curable resin layer or the thermosetting resin layer 32 and reaches the reflective base material 31. However, since the reflective base material 31 is formed of a material having excellent reflective performance, the reflective base material 31. The light is reflected on the surface and passes through the electron beam curable resin layer or the thermosetting resin layer 32 again, and is diffused on the upper surface.

  Thus, the light diffusing member 3 diffuses incident light over a wide range by forming the electron beam curable resin layer or the thermosetting resin layer 32 whose upper surface is roughened on the reflective base material 31. That is, it can be scattered.

  Although FIG. 5 described above shows an example in which the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32 is roughened by embossing, the method of roughening is not limited to embossing.

  For example, as shown in FIG. 6, an electron beam curable resin or a thermosetting resin containing resin beads 34 is applied to the upper surface of the reflective substrate 31, and then an electron beam is irradiated or heat is applied. It is conceivable that the electron beam curable resin layer or the thermosetting resin layer 32 is formed by curing.

As the resin beads 34, for example, urethane beads, nylon beads, acrylic beads, silicon beads, styrene beads, polyester beads, melamine beads, and the like can be used. As described above, since the electron beam curable resin or thermosetting resin of the present embodiment needs to be excellent in durability, weather resistance, and abrasion resistance, the resin beads 34 filled therein are also A material excellent in durability, weather resistance and abrasion resistance is desirable.

  If the diameter of the resin beads 34 is larger than the thickness of the electron beam curable resin or thermosetting resin applied on the reflective substrate 31, the upper surface of the cured electron beam curable resin layer or thermosetting resin layer 32 is The head of the resin bead 34 protrudes and becomes uneven. If a large number of resin beads 34 are contained in the electron beam curable resin or the thermosetting resin, the places where the irregularities are formed are randomized, and the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32 is Roughened.

  The light incident on the electron beam curable resin or the thermosetting resin is reflected by the head of the resin bead 34 and is diffused or scattered. Therefore, the resin bead 34 is formed of a highly reflective material. desirable.

  Thus, in this embodiment, since the light-diffusion member 3 which diffuses the external light reflected by the light control member 2 is provided, the lighting efficiency can be improved. The light diffusing member 3 has an electron beam curable resin layer or a thermosetting resin layer 32 disposed on the reflective substrate 31, and the upper surface of the electron beam curable resin layer or the thermosetting resin layer 32 is roughened. Therefore, incident light can be diffused or scattered over a wide range. Therefore, the light diffusing member 3 not only diffuses the external light reflected by the light control member 2, but also diffuses the illumination light incident on the electron beam curable resin layer or the thermosetting resin layer 32. Not only the efficiency but also the lighting efficiency can be improved.

  The inventor produced the light diffusing member 3 (Example 1) shown in FIG. 5 and the light diffusing member 3 (Example 2) shown in FIG. 6 to produce optical characteristics, weather resistance tests and abrasion resistance. An experiment (Experiment 1) for conducting a sex test was conducted. In Experiment 1, a light diffusing member 3 (Comparative Example 1) made only of a reflective base material 31 having a flat upper surface, a light diffusing member 3 made of only a reflective base material 31 having an upper surface embossed (Comparative Example 2), A light diffusing member 3 (Comparative Example 3) in which resin beads 34 are contained in the reflective base material 31, and a light diffusing member 3 in which the electron beam curable resin layer 32 is arranged on the reflective base material 31 and the upper surface thereof is flattened (Comparison) A comparison with Example 4) was made.

  In the light diffusing member 3 in Examples 1 and 2, an electron beam curable resin layer 32 is disposed on a reflective base material 31. The materials of the reflective base material 31 used in Examples 1 and 2 and Comparative Examples 1 to 4 are the same, and are PET having a biaxially stretched void structure. However, the upper surface of the PET of Comparative Example 2 is embossed, and the resin beads 34 are contained in the PET of Comparative Example 3. The difference between Comparative Example 4 and Examples 1 and 2 is whether the upper surface of the electron beam curable resin layer 32 is flattened or roughened.

  FIG. 7 is a diagram showing the experimental results of Experiment 1. The average value of the total light reflectance in each of the visible light regions 380 to 780 nm of Examples 1 and 2 and Comparative Examples 1 to 4 was measured with a UV-visible spectrophotometer (SHIMAZU UV-3100PC). % Or more. Moreover, the glossiness which shows the reflectance with respect to incident light of 20 degree | times measured with the high gloss gloss checker (HORIBA IG-410) was 40 or more in the comparative examples 1 and 4, and all others were 4 or less. From this, it was found that Comparative Examples 2 and 3 and Examples 1 and 2 were excellent in diffusion performance.

Regarding the weather resistance test in which ultraviolet rays of 60 mW / cm ² were irradiated with a super UV tester (Iwasaki Electric SUV-W231), all of Comparative Examples 1 to 3 showed a change in ΔYI calculated from the reflection spectra before and after the test. That was all. On the other hand, in both Examples 1 and 2, even after the test, the color change was less than 5 and no discoloration was observed.

Regarding the abrasion resistance test in which the steel wool was reciprocated 50 times with a load of 300 g / cm ² , all of Comparative Examples 1 to 3 were visually confirmed after the test. For example, in Comparative Example 3, peeling was confirmed on the resin beads 34. On the other hand, no scratch was observed in any of Examples 1 and 2.

  According to the results of Experiment 1 shown in FIG. 7, the total light reflectance is high, the glossiness is low, there is no discoloration due to the weather resistance test, there is no decrease in reflectance due to the weather resistance test, and scratches due to the abrasion resistance test are also observed. It can be seen that it is only in the case of Examples 1 and 2 that all the conditions are not provided.

  Next, the present inventor used outside lighting light collecting film when the light diffusing member 3 shown in FIG. 5 is installed on an indoor ceiling surface and when a normal white wallpaper is installed on the ceiling surface. While measuring the illuminance of the floor surface and the wall surface when jumping up to the ceiling, an experiment (hereinafter, experiment 2) was performed to measure the color temperature reproducibility of the reflected light. The light diffusing member 3 used in Experiment 2 has an electron beam curable resin layer disposed on a reflective base material 31 having a white biaxially stretched void structure.

  FIG. 8 is a diagram showing the measurement results of Experiment 2. In FIG. As shown in the figure, the total light reflectance was higher than 95% for the light diffusing member 3, whereas it was less than 90% for the white wallpaper. The illuminance of the wall surface connected to the ceiling was 23% higher when the light diffusing member 3 was installed on the ceiling surface than when the white wallpaper was installed on the ceiling surface. The color temperature reproducibility of the reflected light from the ceiling surface was determined as the difference in the Milled value obtained by multiplying the reciprocal of the color temperature measured with a luminance meter (Konica Minolta CL-200A) by 1,000,000. Was less than 2, and white wallpaper on the ceiling was greater than 6. It is known that when the mired value is 5 or more, a human can distinguish the difference in color.

  From the measurement result of FIG. 8, it can be seen that by installing the light diffusing member 3 shown in FIG. 5 on the ceiling surface, the floor surface and the wall surface can be illuminated more brightly than when the white wallpaper is installed on the ceiling surface. Moreover, since the light-diffusion member 3 shown in FIG. 5 is excellent in the reproducibility of the color temperature of reflected light, it can maintain the whole indoors in a uniform atmosphere.

  The aspect of the present invention is not limited to the individual embodiments described above, and includes various modifications that can be conceived by those skilled in the art, and the effects of the present invention are not limited to the contents described above. That is, various additions, modifications, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

    DESCRIPTION OF SYMBOLS 1 Daylighting system, 2 Light control member, 3 Light diffusing member, 4 Window or daylighting tool, 5 Blind, 6 Base material layer, 7 Light control layer, 8 Adhesion layer, 9 Hard-coat layer, 10 Groove, 11 Base part, 12 Louver part, 21 slats, 22 base material layer, 23 light control layer, 24 functional layer, 25 base part, 26 louver part, 31 reflective base material, 32 electron beam curable resin layer or thermosetting resin layer, 33 unevenness, 34 resin beads

Claims (6)

A reflective substrate;
A cured product layer comprising an electron beam curable resin layer or a thermosetting resin layer disposed on the reflective substrate,
A light diffusing member in which a surface of the cured product layer opposite to the reflective substrate is roughened.   The light diffusing member according to claim 1, wherein a surface of the cured product layer opposite to the reflective substrate is embossed. The cured product layer contains a plurality of resin beads,
2. The light diffusing member according to claim 1, wherein a surface of the cured product layer on the side opposite to the reflective substrate has irregularities due to the plurality of resin beads arranged in the surface direction. A first light control member that reflects incident light in a predetermined direction;
A second light control member for diffusing the light reflected by the first light control member,
The second light control member is
A reflective substrate;
A cured product layer comprising an electron beam curable resin layer or a thermosetting resin layer disposed on the reflective substrate,
The daylighting system in which the surface of the cured product layer opposite to the reflective substrate is roughened. Incident light incident on the first light control member is external light,
The lighting system according to claim 4, wherein the second light control member is disposed on an indoor ceiling surface or wall surface.   6. The second light control member according to claim 4 or 5, wherein the second light control member diffuses the light reflected by the first light control member and diffuses the illumination light incident on the second light control member. Daylighting system.

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