WO2016084752A1

WO2016084752A1 - Natural-light collecting sheet and natural-light collecting laminated body

Info

Publication number: WO2016084752A1
Application number: PCT/JP2015/082770
Authority: WO
Inventors: 喜洋金井; 井手上　正人
Original assignee: 大日本印刷株式会社
Priority date: 2014-11-25
Filing date: 2015-11-20
Publication date: 2016-06-02
Also published as: JPWO2016084752A1; JP6135889B2

Abstract

[Problem] To provide a natural-light collecting sheet and natural-light collecting laminated body that can, in response to differences in the height of sunlight due to the season and time of day, make an entire room brighter, and give someone in the room an even greater feeling of comfort without allowing there to be a time period when it becomes unnaturally dark. [Solution] A natural-light collecting sheet 1 includes: a light transmitting part 11 in which a plurality of grooves are formed in one surface thereof, and which transmits light; and a light deflecting part 12 which is formed inside of the plurality of grooves of the light transmitting part 11, and which has a refractive index that is lower than that of the light transmitting part 11. The natural-light collecting sheet is characterized by the following: the light deflecting part 12 has a first upper side 12a and a second upper side 12b on the side that forms the upper part of the light deflecting part, and has a lower side 12d on the side that forms the lower part of the light deflecting part; the first upper side 12a and the second upper side 12b are connected so as to protrude downward; the angle that the lower side 12d forms with the normal line of the one surface of the light transmitting part 11 is 1-6 degrees; and the ratio of the length D of the normal-line direction of the light deflecting part 12 to the pitch P of the light deflecting part is 2.5-3.5.

Description

Daylighting sheet and daylighting laminate

The present invention relates to a daylighting sheet and a daylighting laminate for taking in external light such as sunlight.

It is well known that so-called window glass forms a bright and comfortable indoor space by taking in outside light such as sunlight inside the building. On the other hand, however, if the outside light incident on the window glass is taken into the room as it is, there may be a problem such as feeling glare. On the other hand, several techniques for controlling the direct sunlight and adopting the indoor side in a more comfortable manner have been proposed.

Patent Documents

1 and 2 disclose a daylighting sheet that suppresses direct sunlight (direct light) and that allows efficient daylighting and allows the outdoor side to be viewed from the indoor side.

JP 2014-119737 A Japanese Patent Application Laid-Open No. 2014-119738

The present invention balances productivity and daylighting performance, responds to the difference in altitude of the sun depending on the season and time of day, makes the whole room brighter and does not have an unnaturally dark time zone, and offers higher comfort Provide a daylighting sheet and a daylighting laminate.

The daylighting sheet according to the present invention is:
A light transmitting portion that transmits light from one surface to the other surface;
A light deflection unit having a lower refractive index than the light transmission unit inside the plurality of grooves formed in the light transmission unit;
Have
The light deflection unit has a first side and a second side on one side of the direction in which the light deflection units are arranged, and a third side on the other side,
The first side and the second side are connected so as to protrude from the light transmission part side toward the inside of the light deflection part.

The daylighting sheet according to the present invention is:
The angle formed by the third side and the normal of the one surface of the light transmission part is 1 ° or more and 6 ° or less,
The ratio of the length of the normal direction of the light deflection unit to the pitch of the light deflection unit is 2.5 or more and 3.5 or less.

The daylighting sheet according to the present invention is:
The light transmitting portion of the light that is reflected most strongly among the light reflected by the light deflecting portion with respect to light having an incident angle of 10 ° or more and 60 ° or less that is a normal to the one surface of the light transmitting portion. The angle formed with the normal line on the one surface is not less than 1 ° and not more than 35 °.

The daylighting sheet according to the present invention is:
An angle between the first side and the normal to the one surface of the light transmitting portion is 10 ° or more and 12.5 ° or less,
An angle between the second side and a normal line on the one surface of the light transmission portion is −1.5 ° to 2.5 °.

The daylighting laminate according to the present invention is:
A sheet-like base material layer that transmits light;
The daylighting sheet formed on one surface side of the base material layer;
It is characterized by providing.

The daylighting laminate according to the present invention is:
A hard coat layer formed on the other surface side of the base material layer;
An adhesive layer formed on the opposite side of the daylighting sheet from the base material layer;
It is characterized by providing.

According to the daylighting sheet and daylighting laminate of the present invention, it is possible to achieve both productivity and daylighting performance, cope with the altitude difference of the sun according to the season and time, brighten the whole room and darken the time zone unnaturally. Without it, it becomes possible to give higher occupants more comfort.

The figure which expanded a part of daylighting sheet 1 is shown. The figure explaining the light to jump up of this embodiment is shown. The example of one optical path of the lighting sheet of this embodiment is shown. The other example of a light path of the lighting sheet of this embodiment is shown. The modification of the light deflection | deviation part of the lighting sheet of this embodiment is shown. The layer structure of the lighting laminated body of this embodiment is shown typically. An example of one optical path of the lighting laminated body of this embodiment is shown. The other example of an optical path of the lighting laminated body of this embodiment is shown. The layer structure of the other example of the lighting laminated body of this embodiment is shown typically. The example which applied the lighting sheet of this embodiment to the laminated glass is shown typically. The example which applied the lighting laminated body of this embodiment to the laminated glass is shown typically.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.

FIG. 1 shows an enlarged view of a part of the daylighting sheet 1. In FIG. 1, the left side of the drawing is the outdoor side, the right side of the drawing is the indoor side, the upper side is the top side, and the lower side is the ground side. FIG. 2 is a diagram for explaining the light that jumps up according to the present embodiment.

The daylighting sheet 1 has a light transmission part 11 and a light deflection part 12.

The light transmission part 11 is a part which transmits light, and both surfaces of the part where the light transmission part 11 is arranged in the daylighting sheet 1 are formed substantially in parallel. The surface may be smooth or non-smooth. If smooth, this makes it easier to see the scenery through the daylighting sheet 1. In particular, if the indoor side is non-smooth, the contact area with the base material layer can be increased and the adhesion can be improved, the emitted light can be scattered to reduce the diffraction image, and the scenery through the daylighting sheet 1 can be reduced. Becomes difficult to see and privacy is improved. It is preferable that the light transmitting portion 11 transmits light without scattering. This improves the visibility of the scenery on the back side. Moreover, the fall of the lighting performance by the incident angle to a reflective surface deviating from a total reflection angle by scattering can be suppressed. Here, “transmits without scattering light” means a portion formed without adding a material that intentionally scatters, and inevitably occurs when light passes through the material. Scattering is allowed to occur.

In the present embodiment, the light transmitting portion 11 has a substantially trapezoidal cross section between the two light deflecting portions 12 in the cross section shown in FIG. 1, and has a short upper bottom on the outdoor side and a long lower bottom on the indoor side. Sides forming the interface with the portion 12 are leg portions. However, since the leg portion has a shape that follows the shape of the light deflection portion 12 described later, it is not necessarily a straight line.

Examples of the material constituting the light transmitting portion 11 include transparent resins mainly composed of one or more of acrylic, styrene, polycarbonate, polyethylene terephthalate, acrylonitrile, etc., and epoxy acrylate and urethane acrylate reactive resins (ionizing radiation). Curable resin).

Here, the refractive index of the material constituting the light transmitting portion 11 is preferably in the range of 1.58 or more and 1.61 or less, more preferably 1.59 or more and 1.60 or less from the versatility of the raw materials. If the refractive index is lower than this, sufficient lighting performance may not be obtained. On the other hand, if the refractive index is higher than this, there may be a problem in adhesion and moldability from the viewpoint of material selection.

The light deflection unit 12 is a part formed between two adjacent light transmission units 11. That is, as described above, the light transmission portions 11 are arranged in parallel in the direction along the sheet surface at a predetermined interval, and a concave portion having a predetermined shape is formed between the light transmission portions 11. The concave portion in the present embodiment is a groove having a cross-sectional shape corresponding to the cross-sectional shape of the light deflection unit 12 described later, and the light deflection unit 12 is formed by filling the material constituting the light deflection unit 12 therein. ing. Therefore, the light deflection unit 12 has a cross-sectional shape based on the recess.

The light deflecting unit 12 is a layer configured to be able to deflect the light irradiated here by totally reflecting the light. For this reason, the light deflection unit 12 is filled with a material having a lower refractive index than the light transmission unit 11. According to this, if the incident light satisfies the total reflection condition due to the difference in the refractive index between the light deflecting unit 12 and the light transmitting unit 11 and the angle of the light incident on the interface, the light is totally reflected here. Can be reflected and deflected. As will be described in detail later, the direction of the deflected light is changed, and for example, it can be eliminated from direct light that gives glare by irradiating the ceiling. The refractive index of the material forming the light deflection unit 12 is preferably in the range of 1.45 to 1.51, and more preferably 1.46 to 1.49, from the versatility of the raw materials.

Further, the refractive index difference between the light transmitting portion 11 and the light deflecting portion 12 at that time is preferably 0.07 or more, and more preferably 0.1 or more.

Furthermore, in the present embodiment, the light deflection unit 12 has the following shape.

The light deflection unit 12 has a polygonal shape. Among them, the upper side is formed so that the two

sides

12a and 12b are continuous in the indoor / outdoor direction and protrude downward. That is, the first upper side 12a is arranged on the outdoor side, and the second upper side 12b is arranged on the indoor side. In other words, it has the first upper side 12a and the second upper side 12b on one side in the direction in which the light deflection units 12 are arranged, the lower side 12d on the other side, and the first upper side 12a and the second upper side 12b It is connected so as to protrude from the 11 side toward the inside of the light deflecting unit 12. The first upper side 12a constitutes the first side, the second upper side 12b constitutes the second side, and the lower side 12d constitutes the third side.

When the first upper side 12a and the second upper side 12b are in the posture shown in FIG. 1, the inclination angles θ _U1 and θ are different from each other with respect to the horizontal plane (the normal of the sheet surface of the daylighting sheet 1). _U2 is equipped. Here, θ _U1 and θ _U2 are inclined upward toward the outdoor side (sun side), and θ _U1 is set to an angle larger than θ _U2 . Thereby, in consideration of the altitude of the sun that varies depending on the season and time, it is possible to expand the scene in which sunlight can be totally reflected and deflected at the interface between the light transmission unit 11 and the light deflection unit 12. Therefore, it is preferable that the angle θ _U1 and the angle θ _U2 are also determined from this viewpoint.

In the present embodiment, the angle of attack θ _IN is set to 10 ° to 60 °, and the angle of the light that is most strongly jumped out of the jump angle θ _OUT at each angle of attack θ _IN is 1 ° to 35 °. The daylighting sheet 1 is formed as described above. Splashed angle theta _OUT, light incident from the outside is an angle theta _OUT of jumping chamber, as shown in Table 1 below, it is to determine the brightness uniformity of the chamber. For the angle of the light to be raised, for example, a three-dimensional variable angle spectrocolor measurement system GCMS-11 (Murakami Color) is used as a measuring instrument. As shown in FIG. 2, with respect to the incident light L _IN incident on the sample at an incident angle of 10 ° to 60 ° with an azimuth angle of 0 °, the emitted light L _IN of 0 ° to 70 ° is emitted. The brightness is measured at 1 ° intervals. Then, the light having the highest luminance value is the light that most strongly jumps up.

Here, ○ indicates that the whole room is uniformly brightened, △ indicates that the whole room is bright but partly dark, and X indicates that the part that is felt bright is less than half the whole room. .

In the present embodiment, the angle θ _U1 of the first upper side 12a is 10 ° to 12.5 ° and the angle θ _U2 of the second upper side 12b is −1.5 ° to 2.5 °.

By setting to such an angle, it corresponds to the difference in altitude of the sun according to the season and time, the angle of the light that jumps up most strongly among the jumping angles θ _OUT to the room can be kept within a certain range, It is possible to give the occupants higher comfort without having a time zone in which the entire room is bright and unnaturally darkened.

When the angle θ _U1 of the first upper side 12a is smaller than 10 °, it is difficult to jump up light with a high incident angle. In addition, when the angle θ _U1 of the first upper side 12a is larger than 12.5 °, an incident angle with a weak jumping up exists in the vicinity of 40 °.

If the angle θ _U2 of the second upper side 12b is smaller than −1.5 °, there is a risk that problems may occur in the manufacturing aspects such as mold fabrication and releasability during molding. In addition, when the angle θ _U2 of the second upper side 12b is larger than 2.5 °, it is difficult to jump up light having an incident angle of 10 ° or less.

On the other hand, the lower side 12d on the lower side opposite to the first upper side 12a and the second upper side 12b has an inclination angle of θ _D with respect to the horizontal plane, that is, the normal line on the surface of the transmission part 11. Yes. θ _D is preferably set to 1 ° or more and 6 ° or less from the viewpoint of manufacturing.

The pitch P in which the light deflection units 12 are arranged is not particularly limited, but is preferably 10 μm or more and 200 μm or less. If the pitch P of the light deflection section 12 is too narrow, the shape becomes fine, so that processing becomes difficult during manufacturing. On the other hand, if the pitch P of the light deflection section 12 is too wide, the mold releasability of the material tends to decrease when molding with a mold.

Further, the size of the outer side of the cross section of the light deflection unit 12, that is, the opening side of the recess between the light transmission units 11) is not particularly limited, but is preferably 5 μm or more and 150 μm or less. If this width is too narrow, it becomes a fine shape, making processing difficult. On the other hand, if this width is too wide, the releasability of the material tends to decrease when molding with a mold.

The length of the light deflection unit 12 in the thickness direction (the left-right direction in FIG. 1) is not particularly limited, but is preferably 10 μm or more and 200 μm or less. If this is too short, the processing of the light deflection unit 25 itself may be difficult. On the other hand, if this is too long, the production of the mold for forming the light deflection section 25 and the releasability of the material from the mold may be lowered, and the productivity may be deteriorated.

Further, the aspect ratio Ra of the light deflection unit 12 which is the length in the normal direction on the surface of the transmission unit 11 with respect to the pitch P of the light deflection unit 12 is preferably 2.5 or more and 3.5 or less. By setting such an aspect ratio Ra, it is possible to achieve both productivity and maximum performance.

The main optical path of the daylighting sheet 1 described above will be described. Note that the optical path examples necessary for the description are conceptual, and do not strictly represent the degree of refraction or reflection.

FIG. 3 shows an example of one optical path of the daylighting sheet 1 of the present embodiment.

The light L _S1 shown in FIG. 3 is applied to the daylighting sheet 1 at an incident angle (angle formed from a horizontal plane) _θIN1 based on the solar altitude at that time. The light L _S1 incident on the daylighting sheet 1 is refracted and incident in the light transmitting portion 11. The light L _{S1 that} has passed through the light transmission part 11 reaches the second upper side 12 b in the interface between the light transmission part 11 and the light deflection part 12. At this time, if it is equal to or greater than the total reflection critical angle, it is totally reflected at the interface as shown in FIG. As a result, sunlight is deflected, and light is collected to the back of the room, and direct light that causes glare can be suppressed.

FIG. 4 shows another example of the optical path of the daylighting sheet 1 of the present embodiment.

The light L _S2 shown in FIG. 4 is applied to the daylighting sheet 1 at an incident angle (angle formed from a horizontal plane) _θIN2 based on the solar altitude at that time. The light L _S2 incident on the daylighting sheet is refracted and incident in the light transmitting portion 11. The light L _{S2 that} has passed through the light transmission part 11 reaches the first upper side 12 a in the interface between the light transmission part 11 and the light deflection part 12. At this time, if it is equal to or greater than the total reflection critical angle, it is totally reflected at the interface as shown in FIG. The light L _S1 totally reflected by the first upper side 12 a is transmitted again through the light transmission unit 11 and reaches the second upper side 12 b in the interface between the light transmission unit 11 and the light deflection unit 12. At this time, if it is equal to or greater than the total reflection critical angle, it is totally reflected at the interface as shown in FIG. As a result, sunlight is deflected, and light is collected to the back of the room, and direct light that causes glare can be suppressed.

That is, in the example shown in FIG. 4, sunlight is totally reflected and deflected twice at the first upper side 12a and the second upper side 12b at the interface between the light transmitting unit 11 and the light deflecting unit 12 to cause glare. Prevents light.

As can be seen from the above, according to the daylighting sheet 1, if the inclination angle θ _U1 of the first upper side 12a and the inclination angle θ _U2 of the second upper side 12b have a relationship of θ _U1 > θ _U2 , the light L _S1 , Such as L _S2 , at least a part of sunlight having different traveling angles can be deflected by total reflection and provided to the indoor side, and at least one of the incident amounts of sunlight into the room can be greatly reduced. It becomes possible to eliminate direct light from the part (so-called direct sunlight). Thereby, a bright and comfortable indoor space can be formed.

FIG. 5 shows a modification of the light deflection unit of the daylighting sheet 1 of the present embodiment.

In the example shown in FIG. 5, the opening side 12 f (side facing the outdoor side in the present embodiment) of the groove formed between the light transmitting portions 11 in the light deflecting portion 12 is formed in a recessed shape. .

Further, from the viewpoint of scattering the totally reflected light, the interface between the light deflecting unit 12 and the light transmitting unit 11 may be a mat surface that is a surface on which numerous minute irregularities are formed.

In this embodiment, the lower side 12d is a straight line, but the shape of the lower side is not limited to this, and the lower side 12d is formed by a side having a plurality of angles like the upper side. Also good.

Next, an example in which the daylighting laminate 2 using the daylighting sheet 1 of the present embodiment is bonded to the panel 3 will be described.

FIG. 6 schematically shows the layer structure of the daylighting laminate 2 of the present embodiment.

6 shows the posture in which the panel surface of the daylighting laminate 2 is vertical. In FIG. 6, the left side of the drawing is the outdoor side, the right side of the drawing is the indoor side, the upper side is the top side, and the lower side is the ground side.

The daylighting laminate 2 includes a hard coat layer 21, a base material layer 22, a daylighting sheet 1, and an adhesive layer 23 from the indoor side, and is bonded to the indoor side surface of the panel 3. Hereinafter, each of these layers will be described.

Panel 3 is a plate-like translucent panel having translucency used for a normal building or vehicle window such as a glass panel or a resin panel. Therefore, a known plate glass or resin plate can be used as a member constituting the panel 3.

The hard coat layer 21 is a layer provided on the outermost surface of the daylighting sheet 1 opposite to the panel 3 for the purpose of surface protection. The hard coat layer 21 can be formed as a transparent resin layer, and is preferably formed as a cured resin layer formed by curing a curable resin from the viewpoint of resistance to scratches and surface contamination.

Specifically, ionizing radiation curable resins, other known curable resins, and the like may be appropriately employed according to the required performance. Examples of the ionizing radiation curable resin include acrylate-based, oxetane-based, and silicone-based resins. For example, acrylate-based ionizing radiation curable resins include monofunctional (meth) acrylate monomers, bifunctional (meth) acrylate monomers, (meth) acrylate monomers such as trifunctional or higher (meth) acrylate monomers, urethane (meta ) Acrylate, epoxy (meth) acrylate, polyester (meth) acrylate and other (meth) acrylate ester oligomers or (meth) acrylate ester prepolymers. Examples of tri- or higher functional (meth) acrylate monomers include trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like.

Further, the hard coat layer 21 may be added with a function of improving the stain resistance. This can be achieved, for example, by adding a silicone compound, a fluorine compound, or the like. Further, as other functions, a light scattering function, an antistatic property improvement function, and a water repellency improvement function may be provided.

Examples include those containing spherical particles in the layer for imparting a light scattering function. As the spherical particles, hollow particles such as silica, calcium carbonate, and acrylic, titanium oxide, barium sulfate, magnesium oxide, acrylic beads, urethane beads, and the like can be used. These spherical particles can be formed by appropriately dispersing in a resin. The spherical particles may exhibit a light scattering function due to a difference in refractive index from the cured resin layer within the layer, or may be cueed to exhibit a light scattering function at the air interface. In order to efficiently diffuse light in the visible range, it is preferable to mainly use spherical particles having a diameter in the range of 200 nm to 50 μm.

As materials that can be used for improving the antistatic property, PEDOT-PSS (PEDOT (Poly (3,4-ethylenedioxythiophene); 3,4-ethylenedioxythiophene polymer) and PSS (polynesylsulfonate) are used as the electron conduction type. ); A styrene sulfonic acid polymer)), and the ionic conductive type includes lithium salt materials.

Further, examples of materials that can be used for improving water repellency include fluorine compounds.

The base material layer 22 is a layer serving as a base material for forming the daylighting sheet 1. Therefore, the base material layer 22 has translucency and supports it so that deformation of the daylighting sheet 1 can be prevented. From this point of view, as specific examples of the material constituting the base material layer 22, for example, a transparent resin mainly composed of one or more of acrylic, styrene, polycarbonate, polyethylene terephthalate, acrylonitrile, and the like, epoxy acrylate, urethane acrylate The reactive resin (ionizing radiation curable resin etc.) can be mentioned.

The thickness of the base material layer 22 is not particularly limited, but is preferably 25 μm or more and 300 μm or less. If the thickness of the base material layer 22 is out of this range, there is a risk of causing problems in workability. For example, if the base material layer 22 is too thin, wrinkles are likely to occur. Moreover, if the base material layer 22 is too thick, winding will become difficult in an intermediate process among the processes which manufacture the daylighting sheet 20. FIG.

The refractive index of the base material layer 22 may be the same as or different from the refractive index of the transmission part 11 of the daylighting sheet 1. However, if there is a difference in refractive index between the two, the possibility of light being deflected at the interface increases, so even if they are the same material or different materials, the refractive index difference is small or there is no refractive index difference. It is preferable.

In order to improve the adhesiveness with the light deflection layer 12 provided thereon, the base material layer 22 may be subjected to corona discharge treatment, chromium oxidation treatment, hot air treatment, ozone / ultraviolet treatment method, or the like on one or both sides as desired. A physical or chemical surface treatment such as an oxidation method, a concavo-convex method such as a sand blast method or a solvent treatment method can be applied. In addition, the base material layer 22 may be subjected to a treatment such as forming a primer layer for enhancing adhesiveness. The material used for forming the primer layer is not particularly limited, and examples thereof include acrylic resins, vinyl chloride / vinyl acetate copolymer resins, polyester resins, polyurethane resins, chlorinated polypropylene resins, and chlorinated polyethylene resins. The thickness of the primer layer is preferably 1 to 30 um, and more preferably 1 to 10 um. The surface of the base layer 22 on which the light deflection layer is formed may be smooth, or may be a physical or chemical surface treatment such as the above sandblasting method or a roughening method such as a solvent treatment method, or spherical particles in the primer layer, etc. May be non-smooth.

The adhesive layer 23 is a layer for adhering the daylighting sheet 1 to the panel 3. The material constituting the adhesive layer 23 is not particularly limited as long as it can adhere the daylighting sheet 1 to the panel 3, and a known pressure-sensitive adhesive, adhesive, photo-curing resin, thermosetting resin, or the like is used. it can. As a more specific example, for example, an acrylic pressure-sensitive adhesive can be used as the adhesive layer 23, and more specifically, a pressure-sensitive adhesive in which an acrylic copolymer and an isocyanate compound are combined. However, the material constituting the adhesive layer 23 is preferably made of a material excellent in translucency and weather resistance due to the properties of the daylighting sheet 1.

The thickness of the adhesive layer 23 is not particularly limited, but is preferably 10 μm or more and 100 μm or less. If the adhesive layer 23 is too thin, the adhesion between the panel 3 and the daylighting sheet 1 may be reduced. If the adhesive layer 23 is too thick, it is difficult to make the thickness of the adhesive layer 23 uniform.

The daylighting sheet 1 may be provided with a configuration for adding another function to any one of the above-described layers. For example, an ultraviolet absorber, a heat ray absorber, or a near infrared absorber may be added to provide an ultraviolet ray absorbing function, a heat ray absorbing function, or a near infrared ray absorbing function.

The near-infrared absorbing function can be improved by adding or applying a near-infrared absorber (near-infrared absorbing dye) to one or more of the above layers. As the near-infrared absorbing dye, it is preferable to use one that absorbs a wavelength region of 800 nm to 1100 nm. The near-infrared transmittance in the wavelength region is preferably 20% or less, and more preferably 10% or less. On the other hand, the near-infrared absorbing dye preferably has a sufficient transmittance in the visible light region, that is, in the wavelength region of 380 nm to 780 nm.

The ultraviolet absorbing function can be improved by adding or applying an ultraviolet absorber exemplified below to one or more of the above layers. Examples of ultraviolet absorbers include benzotriazole ultraviolet absorbers (TINUVINＵＶP, TINUVIN P FL, TINUVIN 234, TINUVIN 326, TINUVIN 326 FL, TINUVIN 328, TINUVIN 329, TINUVIN 329 FL, all manufactured by BASF Japan Ltd.), and triazine. UV absorbers (TINUVIN 1577 ED, manufactured by BASF Japan Ltd.), benzophenone ultraviolet absorbers (CHIMASSORB 81, CHIMASORB 81 FL, all manufactured by BASF Japan Ltd.), benzoate UV absorbers (TINUVIN 120, BASF Japan Ltd.) Manufactured).

The heat ray absorbing function can be improved by adding or applying a heat ray absorbent exemplified below to one or more of the above layers. Examples of the heat ray absorbent include metal oxide ultrafine particles such as antimony-doped tin oxide (ATO) or tin-doped indium oxide (ITO) and phthalocyanine compounds.

The daylighting laminate 2 described above is manufactured, for example, as follows.

The light deflection layer 12 of the daylighting laminate 2 can be formed by a method using a die roll. That is, a mold roll is prepared in which irregularities capable of transferring the light transmitting portion 11 of the light deflection layer 12 are provided on the outer peripheral surface of the cylindrical roll. And the base material used as the base material layer 22 is inserted between a die roll and the nip roll arrange | positioned so as to oppose this. And a mold roll and a nip roll are rotated, supplying the composition which comprises the light transmissive part 11 between one side of the base materials 22 and a mold roll. Thereby, the composition which comprises the light transmissive part 11 is filled in the uneven part of the unevenness | corrugation formed in the surface of a metal mold | die roll, and this composition becomes what follows the uneven | corrugated surface shape of a metal mold | die roll.

Here, the above-mentioned composition is preferable as the composition constituting the light transmission part 11, but more specific examples are as follows. That is, a photocurable resin composition comprising a photocurable prepolymer (P1), a reactive diluent monomer (M1), and a high refractive index material (H1) and a photopolymerization initiator (I1) as necessary. Can be used.

Examples of the photocurable prepolymer (P1) include epoxy acrylates such as bisphenol A, bisphenol F, and phenol novolac, urethane acrylates such as hexamethylene diisocyanate, isophorone diisocyanate, polyether acrylates, and polyesters. Examples include acrylate-based and polythiol-based prepolymers.

Examples of the reactive dilution monomer (M1) include reactive monomers such as vinyl pyrrolidone, 2-phenoxyethyl acrylate, 2-ethylhexyl acrylate, β-hydroxy acrylate, and tetrahydrofurfuryl acrylate, and 2-hydroxy-3 -Bifunctional or higher functional monomers such as acryloyloxypropyl methacrylate, polyethylene glycol diacrylate, tetraethylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate and the like.

Examples of the photopolymerization initiator (I1) include hydroxybenzoyl compounds (2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, benzoin alkyl ether, etc.), benzoyl Formate compounds (such as methylbenzoylformate), thioxanthone compounds (such as isopropylthioxanthone), benzophenones (such as benzophenone), phosphate compounds (1,3,5-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6- Trimethylbenzoyl) -phenylphosphine oxide and the like, and benzyldimethyl ketal and the like. Among these, the irradiation device for curing the photocurable resin composition and the curability of the photocurable resin composition can be arbitrarily selected. From the viewpoint of preventing coloring of the light transmitting portion 11, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone and bis (2,4,6-trimethylbenzoyl) are preferable. ) -Phenylphosphine oxide.

Also, examples of the high refractive index material (H1) include materials containing aromatics. Examples thereof include o-phenylphenol EO-modified acrylate, paracumylphenol EO-modified acrylate, bisphenol A diacrylate, and materials having a cardo structure. Examples of the material having a cardo structure include Oxol EA-0200 from Osaka Gas Chemical Company.

These photocurable prepolymer (P1), reactive diluent monomer (M1), high refractive index material (H1), and photopolymerization initiator (I1) are each one type or a combination of two or more types. Can be used.

The composition constituting the light transmission part 11 sandwiched between the mold roll and the base material and filled therein is irradiated with light from the base material side by a light irradiation device. Thereby, the composition which comprises the light transmissive part 11 can be hardened, and the shape can be fixed. And the base material layer 22 and the shape | molded light transmission part 11 are released from a metal mold | die roll with a mold release roll.

Next, the light deflection section 12 can be formed by filling the concave portion of the light transmission section 11 with the composition constituting the light deflection section 12 and curing it. In this way, the light deflection layer 12 can be formed on the base material layer 22.

An adhesive is laminated on the light deflection layer 12 thus formed to form an adhesive layer 23, and the hard coat layer 21 is attached to the base material layer 22 with an adhesive or the like, or a film is formed by coating. As the film forming method, known ones can be used, and gravure coating, bar coating, roll coating, reverse roll coating, comma coating and the like are used. The hard coat layer may be provided before forming the light deflection layer. Thus, the daylighting laminate 2 is obtained.

FIG. 7 shows an example of one optical path of the daylighting laminate 2 of the present embodiment.

The light L _S3 shown in FIG. 7 is applied to the panel 3 based on the solar altitude at that time. The light L _S3 passes through the panel 3 and the adhesive layer 23, and enters the daylighting sheet 1 at an incident angle (angle formed from a horizontal plane) _θIN3 . The light L _S3 incident on the daylighting sheet 1 is refracted and incident on the light transmitting portion 11. The light L _{S3 that} has passed through the light transmission part 11 reaches the second upper side 12 b in the interface between the light transmission part 11 and the light deflection part 12. At this time, if it is equal to or greater than the total reflection critical angle, it is totally reflected at the interface as shown in FIG. Then, the base material layer 22 and the hard coat layer 21 are transmitted. As a result, sunlight is deflected and direct light that causes glare can be suppressed.

FIG. 8 shows another example of the optical path of the daylighting laminate 2 of the present embodiment.

The light L _S4 shown in FIG. 8 is applied to the panel 3 based on the solar altitude at that time. The light L _S4 passes through the panel 3 and the adhesive layer 23 and is irradiated onto the daylighting sheet 1 at an incident angle (angle formed from a horizontal plane) _θIN4 . The light L _S4 incident on the daylighting sheet is refracted and incident in the light transmission part 11. The light L _{S4 that} has passed through the light transmission part 11 reaches the first upper side 12 a in the interface between the light transmission part 11 and the light deflection part 12. At this time, if it is equal to or greater than the total reflection critical angle, it is totally reflected at the interface as shown in FIG. The light L _S1 totally reflected by the first upper side 12 a is transmitted again through the light transmission unit 11 and reaches the second upper side 12 b in the interface between the light transmission unit 11 and the light deflection unit 12. At this time, if it is equal to or greater than the total reflection critical angle, it is totally reflected at the interface as shown in FIG. Then, the base material layer 22 and the hard coat layer 21 are transmitted. As a result, sunlight is deflected and direct light that causes glare can be suppressed.

That is, in the example shown in FIG. 8, sunlight is totally reflected and deflected twice at the first upper side 12a and the second upper side 12b at the interface between the light transmitting unit 11 and the light deflecting unit 12 to cause glare. Prevents light.

As can be seen from the above, according to the daylighting laminate 2, if the inclination angle θ _U1 of the first upper side 12a and the inclination angle θ _U2 of the second upper side 12b have a relationship of θ _U1 > θ _U2 , the light L _{Like S1} and L _S2 , at least part of sunlight having different traveling angles can be deflected by total reflection and provided indoors, and at least without significantly reducing the amount of sunlight entering the room, and at least Part of direct light (so-called direct sunlight) can be eliminated. Thereby, a bright and comfortable indoor space can be formed.

FIG. 9 schematically shows a layer configuration of another example of the daylighting laminate 2 of the present embodiment. Note that FIG. 9 shows a posture in which the panel surface is vertical, with the left side of FIG. 9 being the outdoor side, the right side of the paper being the indoor side, the upper side of the page being the top side, and the lower side of the page being the ground side.

The daylighting laminate 2 shown in FIG. 9 is manufactured by dividing the adhesive layer 23 of the daylighting laminate 2 shown in FIG. 6 into a strong adhesion layer 23a, a base film 23b, and a weak adhesion layer 23c. Further, a protective film 24 may be provided on the opposite side of the hard coat layer 21 from the substrate 22.

The strong adhesive layer 23a is preferably made of an acrylic material containing a curing agent such as isocyanate. The weak adhesive layer 23c is preferably made of an acrylic material containing a curing agent such as isocyanate and a UV absorber. The base film 23b may be polyethylene terephthalate (PET) or the like.

By separating the daylighting laminate 2 from the panel 3 by separating the adhesive layer 23 into the strong adhesion layer 23a, the base film 23b, and the middle adhesion layer 23c, a part of the daylighting laminate 2 remains attached to the panel 3 It becomes possible to suppress remaining.

The protective film 24 may be polyethylene terephthalate (PET) or the like.

FIG. 10 schematically shows an example in which the daylighting sheet 1 of this embodiment is applied to a laminated glass G. Note that FIG. 10 shows a posture in which the glass surface is vertical, with the left side of FIG. 10 being the outdoor side, the right side of the paper being the indoor side, the upper side of the paper being the top side, and the lower side of the paper being the ground side.

The laminated glass G shown in FIG. 10 is configured by installing the daylighting sheet 1 shown in FIG. Thus, by applying the daylighting sheet 1 to the laminated glass G, it is possible to obtain a glass G that achieves both productivity and daylighting performance.

FIG. 11 schematically shows an example in which the daylighting laminate 2 of this embodiment is applied to a laminated glass G. Note that FIG. 11 shows a posture in which the glass surface is vertical, with the left side of FIG. 11 being the outdoor side, the right side of the paper being the indoor side, the upper side of the paper being the top side, and the lower side of the paper being the ground side.

As shown in FIG. 11, the daylighting laminate 2 as shown in FIG. 6 may be applied to the laminated glass G.

In the laminated glass G shown in FIG. 11, the daylighting laminate 2 is installed between the two glasses G. In addition to the daylighting sheet 1 shown in FIG. 1, the layered structure of the daylighting laminate 2 may be provided with the base material tank 22, the hard coat layer 21, and the protective layer 25 shown in FIG. 6. The protective layer 25 is provided for the purpose of preventing deterioration due to component transfer between the adhesive layer 23 and the daylighting sheet 1, and may be polyethylene terephthalate (PET) or the like. Further, an adhesive layer 23 may be provided on the outdoor side and the indoor side of the daylighting sheet 1 or the daylighting laminate 2. As the adhesive layer 23, EVA or PVA is preferably used.

Thus, by applying the daylighting laminate 2 to the laminated glass G, it becomes possible to obtain a laminated glass G that achieves both productivity and daylighting performance. In addition, as a roll-up daylighting screen, it is possible to use the daylighting laminate 2 or the laminated glass as one of the double glazings, or to roll and unfold the daylighting sheet 1 as a shaft. It is also possible to use it.

Examples and comparative examples of the daylighting sheet 1 are shown below. The refractive index N of the light transmitting portion 11 used in each example and comparative example is 1.60, and the refractive index of the light deflecting portion 12 is 1.47.

Table 2 summarizes the manufacturing aptitude with respect to the angles of the first upper side 12a and the second upper side 12b, the flip-up efficiency, and the incident angle that can be flipped up. In each of the examples and the comparative examples, the angles of the first upper side 12a and the second upper side 12b of the light deflection unit 12 are different.

First, the suitability for manufacturing will be explained. Manufacturability mainly relates to mold manufacturing and mold release during molding. ◎ indicates that the mold can be manufactured and the mold releasability at the time of molding is light, ◯ indicates that the mold can be manufactured and releasable, and × indicates that the mold is difficult to manufacture.

In Comparative Example 3, the angle of the second upper side 12b is −2 °, and it is difficult to manufacture the mold, and the manufacturing suitability is not good.

Next, the flip-up efficiency at each incident angle will be described. Each incident angle is the incident angle θ _IN shown in FIGS. The jumping efficiency is a ratio of 1 when all incident light is jumped up. For example, in this embodiment, when the flip-up efficiency produces an efficiency difference of 0.2 or more with respect to the front and rear angles at an incident angle of 10 °, a change in brightness is felt. Therefore, the comparative example 2 in which the flip-up efficiency is 0.49 when the angle is 40 ° and the flip-up efficiency is 0.45 when the angle is 30 ° and 0.45 when the angle is 50 ° is shown in FIG. It is not included in the examples.

In the present embodiment, the incident angle θ _IN is set to 10 ° or more and 60 ° or less. Therefore, as shown in Table 2, Comparative Example 1 in which the maximum incident angle that can be raised is 56 ° cannot be raised at an incident angle θ _{IN that} is larger than 56 °, and thus is included in the example of this embodiment. Absent. Further, Comparative Example 4 in which the minimum incident angle that can be raised is 11 ° cannot be raised at an incident angle θ _IN smaller than 11 °, and thus is not included in the example of this embodiment.

Table 3 summarizes the lighting performance and productivity with respect to the angle and aspect ratio of the lower side 12d. In each example and comparative example, the angle and the aspect ratio of the lower side 12d of the light deflection unit 12 are different.

First, productivity will be explained. Manufacturability mainly relates to mold manufacturing and mold release during molding. ◎ indicates that the mold can be manufactured and the mold releasability at the time of molding is light, ◯ indicates that the mold can be manufactured and releasable, and × indicates that the mold is difficult to manufacture.

In Comparative Example 1, since the lower side angle θ _D is outside the range of 1 ° or more and 6 ° or less, it is difficult to mold, and the manufacturing suitability is not good, and therefore, X is given.

Next, the lighting performance will be described. The lighting performance is the sum of the flip-up efficiency at each incident angle described in Table 1. Each incident angle is the incident angle θ _IN shown in FIGS. The jumping efficiency is a ratio of 1 when all incident light is jumped up. In this embodiment, the lighting performance of each example when the lighting performance of Comparative Example 1 is set to 100.0 is obtained as the lighting performance ratio, and the lighting performance of 85% or more that does not substantially feel the change in brightness cannot be maintained. In this case, a comparative example not included in the example of the present embodiment is used.

For example, Comparative Example 2 has a lighting performance ratio of 83.4%, which is lower than 85%, and is not included in the example of this embodiment. Moreover, since the lighting performance ratio is 83.0% and is less than 85%, the comparative example 3 is not included in the example of this embodiment.

As described above, according to the daylighting sheet 1 of the present embodiment, a plurality of grooves are formed on one surface side, the light transmitting portion 11 that transmits light, and the inside of the plurality of grooves of the light transmitting portion 11, A light deflector 12 having a refractive index lower than that of the light transmitting portion 11, and the light deflector 12 has a first upper side 12a and a second upper side 12b on the upper side, and a lower side on the lower side. 12d, and the first upper side 12a and the second upper side 12b are connected so as to protrude downward, so that both productivity and daylighting performance can be achieved and the difference in altitude of the sun depending on the season and time can be accommodated. It is possible to give the occupants higher comfort without having a time zone in which the entire room is bright and unnaturally darkened.

According to the daylighting laminate 2 of the present embodiment, the angle formed by the lower side 12d and the normal of the one surface of the light transmission part 11 is 1 ° or more and 6 ° or less, and the light with respect to the pitch P of the light deflection unit 12 Since the ratio of the length D in the direction of the normal line of the deflecting unit 12 is 2.5 or more and 3.5 or less, it is particularly possible to achieve both productivity and daylighting performance.

According to the daylighting laminate 2 of the present embodiment, out of the light reflected by the light deflection unit 12 with respect to light having an incident angle of 10 ° or more and 60 ° or less, which is a normal line on one surface of the light transmission unit 11 The angle formed by the normal line on one surface of the light transmission part 11 of the light that is most strongly bounced is 1 ° or more and 35 ° or less. It is possible to give higher occupancy to a room occupant without having a time zone during which the room is bright and unnaturally darkened.

According to the daylighting sheet 1 of the present embodiment, the angle between the first upper side 12a and the normal line on one surface of the light transmitting portion 11 is 10 ° or more and 12.5 ° or less, and the light of the second upper side 12b. Since the angle formed with the normal line on one surface of the transmission portion 11 is not less than −1.5 ° and not more than 2.5 °, it can be easily manufactured with a simple structure.

According to the daylighting laminate 2 of the present embodiment, since the sheet-like base material layer 22 that transmits light and the daylighting sheet 1 formed on one surface side of the base material layer 22 are provided, the strength is high. It can be produced.

According to the daylighting laminate 2 of the present embodiment, the hard coat layer 21 formed on the other surface side of the base material layer 22 and the adhesive formed on the surface side opposite to the base material layer 22 of the daylighting sheet 1. Therefore, it can be easily bonded to a panel such as glass.

As mentioned above, although the lighting sheet 1 and the lighting laminated body 2 have been demonstrated based on some Examples, this invention is not limited to these Examples, Various combinations or deformation | transformation are possible.

DESCRIPTION OF SYMBOLS 1 ... Daylighting sheet 11 ... Light transmission part 12 ... Light deflection | deviation part 12a ... 1st upper side (1st side)
12b ... Second upper side (second side)
12d ... Lower side (third side)
2 ... Daylighting laminate 21 ... Hard coat layer 22 ... Base material layer 23 ... Adhesive layer

Claims

A light transmitting portion that transmits light from one surface to the other surface;
A light deflection unit having a lower refractive index than the light transmission unit inside the plurality of grooves formed in the light transmission unit;
Have
The light deflection unit has a first side and a second side on one side of the direction in which the light deflection units are arranged, and a third side on the other side,
The said 1st edge | side and the said 2nd edge | side are connected so that it may become convex toward the inner side of the said light deflection | deviation part from the said light transmissive part side, The lighting sheet characterized by the above-mentioned.
The angle formed by the third side and the normal line on the one surface of the light transmission part is 1 ° or more and 6 ° or less,
2. The daylighting sheet according to claim 1, wherein a ratio of a length in a direction of the normal line of the light deflection unit to a pitch of the light deflection unit is 2.5 or more and 3.5 or less.
The light transmitting portion of the light that is reflected most strongly among the light reflected by the light deflecting portion with respect to light having an incident angle of 10 ° or more and 60 ° or less that is a normal to the one surface of the light transmitting portion. The daylighting sheet according to claim 1, wherein an angle formed with a normal line on the one surface is 1 ° or more and 35 ° or less.
An angle between the first side and the normal to the one surface of the light transmitting portion is 10 ° or more and 12.5 ° or less,
4. The angle formed between the second side and the normal to the one surface of the light transmission portion is −1.5 ° or more and 2.5 ° or less. 5. The daylighting sheet according to item.
A sheet-like base material layer that transmits light;
The daylighting sheet according to any one of claims 1 to 4, formed on one surface of the base material layer,
A daylighting laminate comprising:
A hard coat layer formed on the other surface side of the base material layer;
An adhesive layer formed on the opposite side of the daylighting sheet from the base material layer;
The daylighting laminate according to claim 5, comprising: