JP2018120145A - Daylighting sheet and daylighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a daylighting sheet which allows for directing sunlight entering through windows to a ceiling inside a building which is not directly irradiated when the sunlight enters at usual incident angles, converting the sunlight into diffusion light that is uniformly diffused in an opening direction, and efficiently irradiating a ceiling surface, innermost wall surfaces furthest from the windows and the like inside the building while suppressing color separation.SOLUTION: A daylighting film comprises a first base material 2 and a second base material 4 laminated together. The first base material 2 has therein a crazed region consisting of molecular bundles and micropores and extending in stripes along a first direction D1. The second base material 4 has protrusions and recesses repeatedly arranged along the first direction D1, forming a concavo-convex pattern that irregularly meanders about a second direction D2 crossing the first direction D1 such that inter-ridge distance varies among ridge lines comprising apexes of the protrusions of the concavo-convex pattern.SELECTED DRAWING: Figure 2

Description

  In the present invention, when sunlight or artificial light (hereinafter may be collectively referred to as “light”) is introduced into the interior of a building such as a house from the outside, it is attached to a window or the like that serves as a light inlet. The present invention relates to a daylighting sheet and a daylighting apparatus.

  Conventionally, a technique using a prism sheet has been proposed as a technique for efficiently collecting light incident on a window of a building such as a house into the building.

  For example, Patent Document 1 discloses an agricultural or architectural film and sheet for the purpose of controlling the lighting of an agricultural film and sheet or a fitting such as a shoji. In this film and sheet, the film-like polymer resin having transparency is subjected to crazing treatment or stretching treatment. Further, there has been proposed a lighting tool that increases the ratio of craze in the film by increasing the processing tension in the processing process, thereby improving the lighting control function based on the visual field controllability and the air permeability.

  Patent Document 2 discloses a light-transmitting support for the purpose of guiding light incident on a window to the ceiling or the back of the room and for easy installation and ensuring a field of view from the room to the outdoors. A daylighting film in which a plurality of unit prisms and a flat surface are formed on at least one of the surfaces has been proposed.

  Further, Patent Document 3 discloses a prism-shaped portion having two inclined surfaces with respect to the plane of the transparent substrate on one side of the transparent substrate for the purpose of enabling sufficient lighting even under low solar altitude conditions. Has a prism array in which a plurality of prisms are arranged, and a lighting prism sheet capable of adjusting an angle formed by one inclined surface of the prism-shaped portion and a perpendicular to the plane of the transparent substrate has been proposed.

  Further, Patent Document 4 proposes a light management structure in which a plurality of polyhedral refractive prisms are arranged in order on one side of an optical substrate for the purpose of turning light such as sunlight in a useful direction. Has been.

JP 2003-339252 A Japanese Patent Laid-Open No. 2008-040021 JP 2010-066755 A Special table 2013-514549 gazette

The prior art disclosed in Patent Document 1 to Patent Document 3 described above is a technique for reflecting light from the upper side, for example, in the direction of a ceiling in a building, or for daylighting.
However, in the above-described prior art, there is a problem that light is reflected in a narrow range in the frontage direction (that is, the horizontal direction) in the building, and it is difficult to light the entire building.
In order to solve this problem, as a result of intensive investigations by the present inventors, two sheets are arranged so that the extending directions of the periodic structures of the sheets having the periodic structures as disclosed in the prior art are orthogonal to each other. A configuration is conceivable, but in such a configuration, when light including a plurality of wavelengths such as sunlight (hereinafter referred to as multicolor light) is collected, the light is reflected in different directions for each wavelength and separated for each color. I found out that there was a problem of being visible (the color separation of light was visually recognized). This color separation of light does not appear in measured values or physical property values such as illuminance and lighting ratio, but is darkness that is visible to the human eye, and this darkness creates a sense of discomfort for people living in the building. .

Based on the above problems, there is a need for a daylighting sheet 1 as shown in FIG. That is, when the light is collected into the building, the window is emitted from above the axis A that is emitted from a light source (not shown) such as the sun that is higher than the window material W of the window and indicates the third direction D3 outside the building. The polychromatic light incident on the material W is emitted toward the ceiling above the third direction D3 in the building (ie, the ceiling direction), and in the first direction D1 (ie, the frontage direction) orthogonal to the third direction D3. Is required to have a daylighting sheet 1 that emits a wide angle and does not separate the colors of the multicolored light in the second direction D2 (that is, the vertical direction) orthogonal to the third direction D3 and the first direction D1. It has been.
Therefore, the present invention can emit multicolor light in the second direction D2 to the same side as the incident direction with respect to the axis A of the multicolor light (in FIG. 1, above the axis A in FIG. 1), and in the first direction D1. Provides a daylighting sheet and a daylighting device capable of emitting polychromatic light at a wider angle.

The present invention has the following configuration.
[1] A daylighting sheet in which a first base material and a second base material are arranged so as to overlap each other, the inside of the first base material is composed of molecular bundles and fine holes, and is striped along the first direction. A craze region extending in a shape is formed, and the second base material is repeatedly uneven along the first direction, and the intervals between the plurality of ridge lines formed by the vertices of the protrusions of the unevenness vary. A daylighting sheet on which a wavy uneven pattern meandering about a second direction intersecting the first direction irregularly is formed.
[2] The first direction is a direction parallel to the floor surface of the building, and the second direction is a direction perpendicular to the floor surface of the building. ] The daylighting sheet | seat of description.
[3] The daylighting sheet according to [1] or [2], wherein the most frequent pitch of the crazing region is 1 μm or more and 30 μm or less.
[4] The daylighting sheet according to any one of [1] to [3], wherein the most frequent pitch of the concavo-convex pattern is 1 μm or more and 30 μm or less.
[5] The second base material includes a resin base material and a resin light diffusion layer provided on one side of the base material, and the uneven pattern is formed on a surface of the light diffusion layer. The daylighting sheet according to any one of the above [1] to [4], which is an uneven pattern forming sheet.
[6] A daylighting apparatus including the daylighting sheet according to any one of [1] to [5].

  According to the daylighting sheet and the daylighting apparatus of the present invention, in the second direction D2, the multi-color light is emitted while being reflected back to the same side as the incident direction with respect to the axis A perpendicular to the surface of the window material W. In the first direction D1 intersecting the direction D2, multicolor light can be emitted at a wider angle, and the light can be collected without being separated for each color.

It is a schematic diagram for demonstrating the lighting in the lighting sheet which concerns on this invention. It is a side view of the lighting sheet which is 1st embodiment which concerns on this invention. It is a perspective view of the 1st substrate which constitutes the lighting sheet which is the first embodiment of the present invention. It is a side view at the time of seeing the 1st substrate shown in Drawing 3 from the 1st direction D1, and is a figure showing signs that the light which entered the 1st substrate reflects. It is a microscope picture of an example of the 1st base material shown in FIG. It is a schematic diagram for demonstrating the manufacturing method of the 1st base material shown in FIG. 3, Comprising: (a) is a 1st example of the manufacturing apparatus of a 1st base material, (b) is manufacture of a 1st base material. It is a 2nd example of an apparatus. It is a perspective view of the 2nd substrate which constitutes the lighting sheet which is the first embodiment of the present invention. It is a perspective view of the 1st example of the original for producing the 2nd substrate which constitutes the lighting sheet which is the first embodiment of the present invention. It is a side view of the lighting sheet which is 2nd embodiment which concerns on this invention. It is a side view of the lighting sheet which is 3rd embodiment which concerns on this invention. It is a figure regarding evaluation of the 1st base material used for the lighting sheet of Example 1, (a) is a mimetic diagram of optical arrangement for performing evaluation, and (b) is light receiver S to the 1st base material. It is a top view which shows the moving direction of. It is a figure regarding evaluation of the 1st base material used for the lighting sheet of Example 1, (a) is a graph which shows light distribution of the 1st base material for every incidence angle, and (b) is based on a lighting sheet. It is a schematic diagram which shows the outline | summary of lighting. It is a graph which shows the incident angle dependence of the polychromatic light in the output ratio of the 1st base material used for the lighting sheet of Example 1. FIG. It is a graph which shows the light distribution of the total light quantity reflected in the craze area | region of the 1st base material used for the lighting sheet of Example 1. FIG. It is a graph which shows the ratio of the reflected light amount integrated value with respect to the total emitted light amount of the 1st base material used for the lighting sheet of Example 1. FIG. It is a graph which shows the incident angle dependence of the diffusion angle in the 1st direction of the 2nd base material used for the lighting sheet of Example 1. FIG. It is a figure which shows the optical arrangement | positioning for measuring the emission characteristic of the polychromatic light of the lighting sheet of Example 1, 2 and Comparative Examples 1-6, Comprising: (a) is a perspective view, (b) is a front view. is there. It is a figure which shows the optical arrangement | positioning for measuring the emission characteristic of the polychromatic light of the daylighting sheet | seat of Example 1, 2 and Comparative Examples 1-6, (a) is a side view, (b) is a top view. is there. It is a schematic diagram for demonstrating the measuring point in the optical arrangement | positioning for measuring the emission characteristic of the polychromatic light of the daylighting sheet | seat of Examples 1, 2 and Comparative Examples 1-6.

  The present invention is a daylighting sheet in which a first base material and a second base material are arranged so as to overlap each other, and the inside of the first base material is composed of molecular bundles and micropores along the first direction. A craze region extending in a striped shape is formed, and the second base material is repeatedly uneven along the first direction, and the intervals between a plurality of ridgelines formed by the vertices of the convex portions of the unevenness vary. The present invention relates to a daylighting sheet on which a wavy uneven pattern meandering about a second direction intersecting the first direction is formed. That is, this invention has a 1st base material and a 2nd base material at least.

  Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following embodiments. In each drawing, dimensions and shapes may be exaggerated for easy understanding. In the following description, as shown in FIGS. 1 and 2, the direction parallel to the floor surface of the building and the surface of the window material W is defined as the first direction D1, parallel to the floor surface of the building, and in the first direction D1. A direction orthogonal to the third direction is defined as a second direction D2, and a direction perpendicular to the first direction D1 and the third direction D3 and parallel to the side wall surface of the building and the vertical direction is defined as a second direction D2.

As shown in FIG. 1, the daylighting sheet 1 according to the present invention is provided, for example, inside a window material W of a window formed on a wall B or the like of a building (not shown) (that is, inside the building), A first base material 2 and a second base material 4 are provided. The first base material 2 and the second base material 4 are overlapped.
Examples of the material of the window material W include glass generally used for windows, and include float glass (that is, single-layer transparent plate glass), tempered glass, ground glass, and the like.

  Hereinafter, a specific configuration example of the daylighting sheet 1 will be described. In addition, this invention includes 1st, 2nd and 3rd embodiment. Further, the present invention is not limited to the first, second and third embodiments.

[First embodiment]
As shown in FIG. 2 (a), the daylighting sheet 1A according to the first embodiment of the present invention has an adhesive layer 8A, an ultraviolet absorbing support 6, an adhesive layer 8B, The one base material 2, the adhesive layer 8C, and the second base material 4 are arranged so as to overlap in this order. The window material W and the daylighting sheet 1A are bonded via an adhesive layer 8A made of an adhesive or the like. That is, the adhesive layer 8 </ b> A is interposed between the building-inside surface Wb of the window material W and the window-side incident surface 2 a of the first base material 2.

The adhesive layer 8A is an arbitrary layer and may or may not be present. The adhesive layer 8A is for adhering the window material W and the ultraviolet absorbing support 6, and there is no particular limitation on the adhesive constituting the adhesive layer 8A. It can be appropriately selected and used according to the above. Specific examples of the adhesive include acrylic, urethane, and silicone adhesives from the viewpoint of weather resistance and transparency. When the adhesive layer 8A is used, the material of the adhesive layer 8A is that the window material W and the ultraviolet absorbing support 6 can be bonded, and the incident light with respect to the material of the window material W and the material of the ultraviolet absorbing support 6 is used. There is no particular limitation as long as it has an appropriate refractive index considering the refractive index at the wavelength of (for example, sunlight). On the other hand, when the adhesive layer 8A is not used, it is possible to fix the daylighting sheet 1A and the window material W with a fixture or the like. Examples of the fixing position include the daylighting sheet 1A and the end of the window material W.

  In the ultraviolet absorbing support 6, the first base material 2 and the second base material 4 are deteriorated by irradiating the first base material 2 and the second base material 4 with ultraviolet light included in incident light incident on the window material W. In this case, the material is made of a material that can absorb ultraviolet rays contained in such incident light. However, the ultraviolet absorbing support 6 may be omitted when the incident light does not include ultraviolet rays or when the material of the first base material 2 or the second base material 4 is resistant to ultraviolet rays.

  The adhesive layer 8B is an arbitrary layer and may or may not be present. The adhesive layer 8B is for adhering the ultraviolet absorbing support 6 and the first substrate 2, and is not particularly limited as an adhesive constituting the adhesive 8B. Among the various conventionally known adhesives Can be appropriately selected according to the situation. Specific examples of the adhesive include acrylic, urethane, and silicone adhesives from the viewpoint of weather resistance and transparency. In the case where the adhesive layer 8B is used, the material of the adhesive layer 8B can adhere the ultraviolet absorbing support 6 and the first base 2 and the material of the ultraviolet absorbing support 6 and the first base 2 There is no particular limitation as long as it has an appropriate refractive index in consideration of the refractive index at the wavelength of incident light with respect to the material. On the other hand, when the adhesive layer 8B is not used, fixing the ultraviolet absorbing support 6 and the first substrate 2 with a fixture or the like can be mentioned. Examples of the fixing position include the ultraviolet absorbing support 6 and the end of the first substrate 2.

  The first base material 2 is emitted from a light source such as the sun at a position higher than the building window in the arrangement shown in FIG. 1 and is incident on the window material W from above the axis A indicating the third direction D3 outside the building. This is for emitting polychromatic light toward the ceiling above the third direction D3 in the building (that is, toward the ceiling). The first direction D1 is parallel to the floor surface of the building.

The first base material 2 will be described in more detail.
The 1st base material 2 is a base material in which the craze area | region 8 which consists of a molecular bundle | flux and a micropore and extends in stripes along a 1st direction is formed inside. Here, since the first base material 2 in the present invention is preferably composed of a polymer resin film as will be described later, the first base material 2 is hereinafter assumed to be composed of a polymer resin film. One substrate 2 will be described.

  The craze region 8 includes a surface craze appearing on the surface of the substrate and an internal craze generated inside, and indicates a region having a fine cracked pattern. The craze region 8 formed on the first substrate is generally composed of molecular bundles (fibrils) and voids, and has a structure similar to a sponge as a whole (see FIG. 5, microscope: JSM6460LA, manufacturer: Japan). Electronics Corporation). The molecular bundle can also be said to be a fiberized portion formed in a strip shape parallel to the width direction. A void is also called a hole, and there are an infinite number so as to communicate discontinuously inside the craze region 8. The size of the void is not limited, but is, for example, 5 nm to 20 nm in diameter. The craze region 8 is preferably formed in a stripe shape from the viewpoint of daylighting use. Here, the striped shape means a state in which the craze regions 8 are formed in parallel or substantially in parallel. Craze region 8 may be formed at random intervals, or may be formed at regular intervals.

  The voids in the craze region 8 of the first base material 2 in which the craze region 8 is formed may be a gas such as air, or may be filled with a colorant, a stabilizer, a conductive polymer, or the like. A gas (particularly air) is preferred.

The thickness of the first substrate 2 is preferably 0.5 μm to 1000 μm, more preferably 1 μm to 800 μm, further preferably 2 μm to 500 μm, and particularly preferably 10 μm to 300 μm, It is very preferable that it is 50 micrometers-200 micrometers.
The crazed region 8 formed in a striped shape is preferably substantially parallel to the direction of molecular orientation of the polymer resin film 20. The width of the craze region 8 is preferably 0.5 μm to 100 μm, more preferably 1 μm to 50 μm, still more preferably 2 μm to 30 μm, and particularly preferably 4 μm to 10 μm. The interval (pitch) in the second direction D2 between the craze region 8 and the craze region 8 is preferably 0.1 μm to 1000 μm, more preferably 1 μm to 800 μm, and even more preferably 1 μm to 100 μm. It is more preferably 1 μm to 50 μm, particularly preferably 1 μm to 30 μm, particularly preferably 5 μm to 30 μm, more particularly preferably 10 μm to 30 μm, and preferably 20 μm to 30 μm. Most preferred. The most frequent pitch in the second direction D2 between the craze region 8 and the craze region 8 is preferably 0.1 μm to 1000 μm, more preferably 1 μm to 800 μm, and more preferably 1 μm to 100 μm, like the above pitch. Is more preferably 1 μm to 50 μm, particularly preferably 1 μm to 30 μm, particularly preferably 5 μm to 30 μm, more preferably 10 μm to 30 μm, and more preferably 20 μm to 30 μm. Most preferably.

  In this invention, a commercial item can be used for the 1st base material 2 provided with the structure mentioned above. As the 1st base material 2, the monotran (trademark) film made from NAC Co., Ltd. is mentioned, for example.

  In the first base material 2, the second direction D <b> 2 shown in FIG. 1 is the width direction of the craze region 8, and the first direction D <b> 1 shown in the same drawing is the length direction of the craze region 8. That is, the first base material 2 is arranged with the width direction of the craze region 8 facing the second direction D2 and the length direction of the craze region 8 facing the first direction D1.

  In the first substrate 2, as shown in FIG. 4, the incident angle from the third direction D3 perpendicular to the incident surface 2a is 0 °, and the direction approaching the upper end of the incident surface 2a from the axis A is + (positive). For example, the reflected light integrated value when the incident light is incident on the incident surface 2a at + 30 ° to + 60 ° is 25% or more of the incident light amount, and the reflection when the incident light is incident at + 30 ° to + 50 °. It is preferable that the light integrated value is 30% or more of the incident light amount. By satisfying these conditions, the polychromatic light incident on the window material W is emitted toward the second substrate 4 with high efficiency.

  In the first substrate 2, 95% or more of the total integrated value of the reflected light emitted from the emitting surface 2b is continuously distributed within the range of the peak angle ± 20 ° of the reflected light integrated value. Is preferred. By satisfying this condition, the light flux having the scattering degree of light emitted from the second substrate 4 (range of light distribution) having a width of about 40 ° in the vertical direction and a width of about 30 ° in the parallel direction. Thus, the light is emitted with high efficiency, and the room can be efficiently illuminated. In order to develop the above-described emission characteristics with respect to incident light, the most frequent pitch in the second direction D2 of the crazing region 8 in the first substrate 2 is preferably 1 μm or more and 30 μm or less, and is 10 μm or more and 30 μm or less. More preferably.

In the first base material 2, for example, the reflected light emitted in the + direction (that is, the ceiling direction) with respect to the axis A out of the total emitted light amount when the incident light is incident on the incident surface 2 a at + 30 ° to + 70 °. The ratio of the integrated values is 40% or more. For example, the integrated value of the reflected light emitted in the + direction with respect to the axis A out of the total emitted light amount when the incident light is incident on the incident surface 2a at + 40 ° to + 60 °. The ratio is preferably 50% or more of the incident light amount. By satisfying these conditions, the polychromatic light incident on the window material W is emitted above the third direction D3 in the building (that is, the ceiling direction), that is, in the + direction with respect to the axis A, and the lighting is performed well. Is called.
In order to develop the above-described emission characteristics with respect to incident light, the most frequent pitch in the second direction D2 of the crazing region 8 in the first substrate 2 is preferably 1 μm or more and 30 μm or less, and is 10 μm or more and 30 μm or less. More preferably.

  In the present invention, the first base material 2 is preferably formed by molding a resin composition containing a resin component (preferably a thermoplastic resin) into a polymer resin film, and then subjecting the polymer resin film to a crazing treatment. By doing so, it is obtained by forming the craze region 8 in a striped pattern. In this specification, the crazing treatment refers to applying an external force to the polymer resin film by stretching or pressing the polymer resin film, and gradually shearing the molecular bundle at the external force applying portion (that is, the initial stage of the molecular bundle). This refers to a process for generating a surface craze and an internal craze. When the material of the polymer resin film is transparent (when it has transparency), the crazing treatment hardly reduces the transparency of the material, and the polymer resin film obtained by the crazing treatment retains its transparency. It becomes. The polymer resin film obtained using a thermoplastic resin is not particularly limited in its production method, and can be obtained by applying various molding methods. For example, it is industrially advantageous to apply a T-die extrusion method that is generally widely used or an inflation method that performs blow-up.

  The first substrate 2 of the present invention is composed of a polymer resin film having orientation in a desired direction because it is easy to form the craze region 8 in a stripe shape along the orientation direction. Is preferred. The degree of orientation is (a) resin temperature at the time of molding, (b) take-up speed, (c) cooling rate, (d) molecular weight of resin, (e) molecular weight distribution of resin, (f) molecular structure of resin Can be controlled by changing (g) the draw ratio, particularly in the case of the T-die method, and (h) blow-up ratio, etc., particularly in the case of the inflation method. Therefore, it is possible to produce a film having an orientation degree in a desired preferable range by appropriately controlling the requirements (a) to (g). When the degree of orientation is insufficient, the film can be stretched to obtain an appropriate degree of orientation.

  As the resin (polymer resin) component constituting the first base material 2, a thermoplastic resin or a thermosetting resin that is transparent or translucent and capable of forming a base material (eg, film) is particularly preferable. Any of them can be adopted without limitation, but a thermoplastic resin is preferable from the viewpoint of easiness of formation of the craze region 8 and the like.

Examples of the thermoplastic resin include olefin resin, polyester, polyamide, polyimide (PI), styrene resin, polycarbonate, halogen-containing thermoplastic resin, and nitrile resin. Among these thermoplastic resins, it is preferable to use at least one selected from the group consisting of an olefin resin, a polyester, a styrene resin, and a halogen-containing thermoplastic resin from the viewpoint of moldability to a film and an economical viewpoint. At least one selected from the group consisting of a polyolefin and a cycloolefin copolymer is more preferable, and at least one selected from the group consisting of a polypropylene and a cycloolefin copolymer is more preferable.
A resin component may be used individually by 1 type, and may be used in mixture of 2 or more types. The resin component may be a resin obtained by copolymerizing each other. The first substrate 2 may be a single layer or a multilayer (two or more layers). In view of the ease of forming the crazing region 8 at room temperature, a resin having a glass transition temperature of −45 ° C. or higher, preferably −30 ° C. or higher, particularly preferably −15 ° C. or higher is used. Is desirable. When using the resin composition for monolayering or multilayering when forming the first substrate 2, it is preferable that the glass transition temperature of the thermoplastic resin as the main constituent component is in the above range.

  Examples of the olefin resin include polyolefin and cycloolefin copolymer (COC). Examples of the polyolefin include polyethylene (eg, low density branched polyethylene, high density linear polyethylene, low density linear polyethylene, etc., also referred to as PE), polypropylene (eg, isotactic polypropylene, syndiotactic polypropylene, etc., also referred to as PP). .), Poly (1-butene), poly (4-methyl-1-pentene), and the like. Examples of the cycloolefin copolymer include a cycloolefin copolymer obtained by copolymerizing ethylene and norbornene.

Examples of the polyester include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polynaphthalene terephthalate.
Examples of polyamide (PA) include nylon-4, nylon-6, nylon-6,6, nylon-4,6, nylon-12, amorphous nylon and the like. Preferable polyamide is at least one selected from the group consisting of nylon-6, nylon-6,6 and amorphous nylon.

  Examples of the styrene resin include polystyrene (PS), rubber graft polystyrene (HIPS), and acrylonitrile / butadiene / styrene copolymer (ABS).

  Examples of the polycarbonate include fragrances composed of 2,2-bis (4-oxyphenyl) alkane, bis (4-oxyphenyl), ether, bis (4-oxyphenyl) sulfone, sulfide, or sulfoxide bisphenols. Group polycarbonate can be exemplified.

  Examples of the halogen-containing thermoplastic resin include homopolymers of polyvinylidene fluoride, copolymers with tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, vinylidene chloride, polytetrafluoroethylene (PTFE), and the like. .

  Examples of the nitrile resin include acrylonitrile, methacrylonitrile, and mixtures thereof.

  An embodiment in which a crazed region is formed in a stripe shape in a polymer resin film substantially parallel to the molecular orientation direction will be described. In order to form the craze region in the polymer resin film in a striped pattern, for example, using an apparatus as shown in FIG. 6A, it is easy to adjust the width of the craze region, the separation of the craze region, and the like. Therefore, it is preferable. That is, the craze forming apparatus shown in FIG. 6A includes, for example, a crazing processing machine including a support P having a sharp edge at the tip and a guide roller, and a tension applying mechanism (not shown). Become. The polymer resin film 20 held in a tensioned state is brought into contact with the edge of the support (the tip of P) in a direction substantially parallel to the molecular orientation direction, and the polymer resin film 20 is locally bent so as to be deformed. And the creasing region can be continuously formed in stripes in a direction substantially perpendicular to the moving direction by gradually moving the bending deformation region relative to the polymer resin film. . In order to move the bending deformation region relative to the polymer resin film, (A) maintaining the bending angle of the deformation of the polymer resin film 20, the support P and the guide roller are integrated with the polymer resin film. A structure in which the polymer resin film 20 is moved; or (B) a structure in which the polymer resin film 20 is moved with respect to the support P and the guide roller while maintaining the bending angle of deformation of the polymer resin film 20 is possible.

  According to the structure of (A), it is possible to repeatedly perform the crazing process a plurality of times at an arbitrary distance required over the length direction of the polymer resin film, and the polymer resin film 20 is more easily and regularly arranged. It is preferable because a continuous craze region 8 can be formed. Moreover, in order to form the regular and continuous craze area | region 8, it is preferable to set the tension | tensile_strength provided to the polymer resin film 20 comparatively low, and to repeat a crazing process in multiple times. The formation of the craze region 8 in a direction substantially parallel to the molecular orientation direction in this way is because the craze region 8 is formed relatively easily by pulling in the direction perpendicular to the molecular chain orientation direction. This is considered to be because it is difficult to form the craze region 8 in a direction perpendicular to the direction.

  In the above description, the craze regions 8 are formed in stripes on the polymer resin film having orientation in a desired direction. However, when the craze regions 8 are formed in stripes on the non-oriented polymer resin film. It is preferable to form the craze region 8 in a striped pattern using an apparatus as shown in FIG. 6B because it is easy to adjust the width of the craze region 8, the distance between the craze regions 8, and the like. That is, in the craze forming apparatus shown in FIG. 6B, the polymer resin film 20 held in tension is brought into contact with the edge 31a of the support 31, and the polymer resin film 20 is locally bent and deformed. A craze region 8 is continuously formed in a stripe shape in a direction substantially perpendicular to the moving direction by gradually moving the bending deformation region relative to the polymer resin film. be able to. As disclosed in JP-A-11-231108, the craze region 8 may be formed in a striped pattern by stretching the polymer resin film.

  The tension applied to the polymer resin film 20 in order to form the craze region 8 on the polymer resin film 20 in a striped pattern using the craze forming apparatus shown in FIG. However, it is preferably 90% or more and less than 100% of the breaking stress. The edge angle α of the support P is not limited, but is preferably 50 degrees or less, and more preferably 30 degrees or less. Further, the bending angle θ of the polymer resin film 20 is not limited, but is preferably 140 degrees or less, more preferably 120 degrees or less, and further preferably 110 degrees or less. The moving speed is not limited, but is preferably 100 mm / min or less, and particularly preferably 10 mm / min to 4 mm / min.

  The width of the craze regions 8 formed in the polymer resin film 20, the spacing between the craze regions 8, the ratio of the number of penetrated craze regions 8, and the like indicate the degree of molecular orientation of the polymer resin film 20 and the craze region 8. The temperature and speed at the time of formation, the tension of the polymer resin film 20 (tension in the tension state), the edge angle α of the support, the bending angle θ of the film, and the like can be adjusted. For example, when the tension at the time of forming the craze region 8 is increased or the bending angle θ is decreased, the interval between the craze regions 8 formed in a stripe shape is narrowed, and the ratio of the number of penetrated craze regions 8 is increased. To do. In addition, if a crazing process is performed in multiple times, the craze area | region 8 can be grown also to a depth direction.

  The adhesive 8C is an arbitrary layer and may or may not be present. The adhesive layer 8C is for adhering the first base material 2 and the second base material 4, and there is no particular limitation on the adhesive constituting the adhesive 8C, and among various conventionally known adhesives. Can be appropriately selected according to the situation. Specific examples of the adhesive include acrylic, urethane, and silicone adhesives from the viewpoint of weather resistance and transparency. In addition, when using the adhesive layer 8C, the material of the adhesive layer 8C can adhere the first base material 2 and the second base material 4 described later, and the first base material 2 and the second base material are used. There is no particular limitation as long as it has an appropriate refractive index in consideration of the refractive index at the wavelength of incident light for the material of No. 4. On the other hand, when the adhesive layer 8C is not used, fixing the first base material 2 and the second base material 4 with a fixture or the like can be mentioned. As for the fixing position, the edge part of the 1st base material 2 and the 2nd base material 4 is mentioned, for example.

  As shown in FIG. 7, the second base material 4 is for emitting the multicolor light emitted from the first base material 2 at a wide angle in the first direction D1 (ie, the frontage direction) orthogonal to the third direction D3. It is.

The second substrate 4 will be described in more detail.
The second base material is irregularly repeated along the first direction, and each of the second base material irregularly intersects the first direction so that the intervals between the ridge lines formed by the vertices of the convex portions of the unevenness vary. It is a base material in which a wavy uneven pattern meandering about the second direction is formed.
The second substrate 4 is [i] a substrate composed of a transparent substrate 11, [ii] a transparent substrate 11, and a predetermined surface on the surface opposite to the substrate 11 in contact with the substrate 11. And a base material having a light diffusing layer 12 in which a concavo-convex pattern is formed so that the concavo-convex pattern is repeated along the direction. That is, the second base material 4 may be a single-layer base material composed of the transparent base material 11 or a multi-layer base material in which the light diffusion layer 12 is laminated on the transparent base material 11. May be.
The concavo-convex pattern is preferably a wavy concavo-convex pattern. As for the 2nd base material 4, the 1st direction D1 shown in FIG. 1 turns into the said predetermined direction, ie, the direction where the unevenness | corrugation is repeated. That is, the 2nd base material 4 is arrange | positioned toward the 1st direction D1 in the direction where the unevenness | corrugation is repeated.
In addition, the base material 11 and the light-diffusion layer 12 may be integrated.

  The concavo-convex pattern of the second base material 4 changes irregularly so that the intervals between the plurality of ridge lines formed by the vertices of the convex portions of the concavo-convex vary, and the second direction intersects the first direction as a center. It is a meandering uneven pattern. Moreover, in the said uneven | corrugated pattern of the 2nd base material 4, it is preferable that the height dimension of the said unevenness | corrugation is changing irregularly. And it is preferable that the heights of the plurality of ridge lines made up of the vertices of the projections and depressions of the unevenness also change irregularly, and the heights of the plurality of valley lines 12b made up of the bottom ends of the unevenness also change irregularly. .

  The concavo-convex pattern preferably has a mode pitch of 1 μm to 30 μm, and the average depth of the bottom of the concavo-convex pattern is preferably 10% or more when the mode pitch is 100%. The aspect ratio of the concavo-convex pattern is preferably 0.1 or more and 1.0 or less.

Although it does not specifically limit as the base material 11 of the 2nd base material 4, For example, the base material which has resin components, such as a thermoplastic resin and a thermosetting resin, as a main component is mentioned. The resin component can be used alone or in combination of two or more.
As the thermoplastic resin, acrylic resin (for example, poly (meth) methyl acrylate, poly (meth) ethyl acrylate, etc. (meth) acrylic acid means acrylic acid or methacrylic acid), polyamide, polyolefin ( For example, polyethylene, polypropylene, etc.), polycarbonate, polyester (eg, polyethylene terephthalate, polyethylene naphthalate, etc.), polystyrene, polyphenylene sulfide, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer resin (ABS resin), acrylonitrile-styrene copolymer Resin, polyacetal, polyvinyl alcohol, polyvinylidene chloride, polyetherimide, acetylcellulose, nitrocellulose, cellulose propionate, ethylcellulose, etc. It is.
Examples of the thermosetting resin include phenol resin, epoxy resin, melamine resin, urea resin, unsaturated polyester resin, polyurethane resin, silicone resin, diallyl phthalate resin, and silicone resin.

The light diffusion layer 12 of the second substrate 4 is not particularly limited as long as fine irregularities can be transferred. Examples thereof include ionizing radiation curable resins, thermosetting resins, thermoplastic resins, and the like, and ionizing radiation curable resins. Is preferred.
Examples of the ionizing radiation curable resin include an ultraviolet curable resin and an electron beam curable resin. The type of ionizing radiation to be irradiated is appropriately selected according to the type of resin. In general, the ionizing radiation often means ultraviolet rays and electron beams, but in the present specification, visible rays, X-rays, ion rays and the like are also included.

  Examples of ionizing radiation curable resins include epoxy acrylate, epoxidized oil acrylate, urethane acrylate, unsaturated polyester, polyester acrylate, polyether acrylate, vinyl / acrylate, polyene / acrylate, silicon acrylate, polybutadiene, and polystyrylmethyl methacrylate. Resins having structural units derived from monomers such as polymers, aliphatic acrylates, alicyclic acrylates, aromatic acrylates, hydroxyl group-containing acrylates, allyl group-containing acrylates, glycidyl group-containing acrylates, carboxy group-containing acrylates, and halogen-containing acrylates. It is done. Among them, it is preferable to use a polymer (including a prepolymer) containing epoxy acrylate as a monomer.

  Moreover, as thermosetting resin, the resin similar to each thermosetting resin specifically illustrated with resin as a main component which comprises the base material 11 can be mentioned. Moreover, as a thermoplastic resin, the same resin as each thermoplastic resin specifically illustrated with resin as a main component which comprises the base material 11 can be mentioned.

Moreover, in order to improve the light diffusibility of the 2nd base material 4, the base material 11 consists of the light-diffusion agent which consists of an inorganic compound, and an organic compound in the range which does not impair optical characteristics, such as a light transmittance. An organic light diffusing agent can be included.
Examples of the inorganic light diffusing agent include silica, white carbon, talc, magnesium oxide, zinc oxide, titanium oxide, calcium carbonate, aluminum hydroxide, barium sulfate, glass, mica and the like.
Examples of the organic light diffusing agent include styrene polymer particles, acrylic polymer particles, and siloxane polymer particles. These light diffusing agents can be used alone or in combination of two or more.
The content of the light diffusing agent is preferably 10 parts by mass or less with respect to 100 parts by mass of the first resin, which will be described later, because it is difficult to impair the light transmittance.

In order to further improve the light diffusibility of the second substrate 4, the substrate 11 can contain fine bubbles within a range that does not significantly impair optical characteristics such as light transmittance. The fine bubbles have little light absorption and are difficult to reduce the light transmittance.
As a method for forming fine bubbles, a foaming agent is mixed into the base material 11 (for example, a method disclosed in Japanese Patent Laid-Open Nos. 5-2112811 and 6-107842), or an acrylic foamed resin is foamed. A method (for example, a method disclosed in Japanese Patent Application Laid-Open No. 2004-2812) containing fine bubbles after treatment can be applied. Furthermore, a method of causing fine bubbles to foam non-uniformly at a specific position (for example, a method disclosed in Japanese Patent Application Laid-Open No. 2006-124499) is preferable in that more uniform surface irradiation is possible.
The light diffusing agent and the fine foam can be used in combination.

  As a method for producing the second substrate 4, there is a method of performing a transfer step of transferring fine irregularities of the original plate 40 to another material using the original plate 40 shown in FIG. 8. In this example, the fine irregularities formed on the surface of the hard layer 42 of the original 40 are transferred to another material to obtain a primary transfer product having a reverse pattern of the fine irregularities of the original 40 on the surface, and then the above 1 The reverse pattern of the next transfer product is transferred to another material to obtain the second substrate 4 that is a secondary transfer product. As the transfer step, for example, a publicly known method disclosed in Japanese Patent No. 4683011 can be adopted.

Specifically, for example, an uncured ionizing radiation curable resin-containing resin composition containing a release agent is 1 μm or more and 100 μm or less (preferably 3 μm or more and 30 μm or less) with respect to the fine unevenness of the original plate 40 shown in FIG. It is applied with a coater such as a T-die coater, a roll coater or a bar coater so as to be within the thickness. Next, the resin composition is cured by irradiating with ionizing radiation, and then the original plate 40 is peeled off to obtain a primary transfer product. The primary transfer product has a reversal pattern of fine irregularities of the original 40. On the other hand, a transparent substrate 11 is prepared, and an uncured ionizing radiation curable resin-containing resin composition is applied on one surface thereof with a thickness that sufficiently covers fine irregularities. And the said primary is so that the surface which has the inversion pattern of the primary transfer product obtained previously may be pressed with respect to the layer (coating film) of the apply | coated uncured ionizing radiation curable resin containing resin composition. The transfer product is pressed, and then the ionizing radiation curable resin is cured by irradiating with ionizing radiation, and then the primary transfer product is peeled off. Irradiation with ionizing radiation may be performed from either one of the primary transfer product side and the transparent substrate 11 side having ionizing radiation transparency. Accordingly, the transparent substrate 11 and the light diffusing layer 12 including the ionizing radiation curable resin cured product formed on one surface thereof are formed, and fine irregularities are formed on the surface of the light diffusing layer in FIG. The second substrate 4 shown (that is, the secondary transfer product) is obtained.
Further, instead of the above-mentioned uncured ionizing radiation curable resin-containing resin composition, the thermoplastic resin constituting the second base material or the resin composition thereof is molded so that the fine irregularities of the original plate 40 are filled. A molded product in which the fine unevenness is transferred to the surface may be produced, and this molded product may be used as the second substrate. It does not specifically limit as a shaping | molding method, For example, injection molding etc. are mentioned.

  Further, nickel, copper, silver, gold, or other metal plating is performed on the fine irregularities of the original plate 40 shown in FIG. 8 to deposit a plating layer having a thickness of, for example, 200 μm or more and 500 μm or less, and then the original plate is peeled off. You can also obtain a metal primary transfer product. The metal primary transfer product also has a reversal pattern of the fine irregularities of the original. A secondary transfer product can also be obtained from a metal primary transfer product by the same transfer method as that described above.

In the above-mentioned process, it is preferable to dilute the uncured ionizing radiation curable resin with a solvent or the like. A fluororesin, a silicone resin, or the like may be added to the uncured ionizing radiation curable resin-containing resin composition. When the uncured ionizing radiation curable resin is ultraviolet curable, it is preferable to add a photopolymerization initiator such as acetophenones and benzophenones to the uncured ionizing radiation curable resin-containing resin composition. . Moreover, it is preferable to contain acrylic ester in uncured ionizing radiation-curable resin-containing resin composition. Examples of the acrylic ester include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and the like. In addition, (meth) acrylate means an acrylate or a methacrylate.
As long as the fine unevenness can be transferred, the specific method is not limited.

  When a thermosetting resin is used as the material of the light diffusion layer 12, for example, a liquid uncured thermosetting resin-containing resin composition is applied to fine irregularities and cured by heating. In the case of using a thermoplastic resin, there is a method in which a sheet of a thermoplastic resin is used, heated and softened while being pressed against fine irregularities, and then cooled.

  In addition, as described above, in the case of producing a secondary transfer product, for example, a method using a plating roll described in Japanese Patent No. 4683011 is also exemplified. Specifically, first, a long sheet-like material is manufactured as an original plate, the original plate is rounded and attached to the inside of a cylinder, plating is performed with a roll inserted inside the cylinder, and the roll is removed from the cylinder. Take out and obtain a plating roll (primary transfer product). Subsequently, the 2nd base material 4 (namely, secondary transfer product) is obtained by transferring the fine unevenness | corrugation of the said plating roll.

  As the original plate, either a single wafer type or a web type can be used. If a web type master is used, a web type primary transfer product and a secondary transfer product can be obtained. In the single-wafer type, a stamp method using the single-wafer type original as a flat plate, a roll imprint method using a single-wafer type original wound around a roll as a cylindrical die, and the like can be applied. Further, a single-wafer type master may be arranged inside the mold of the injection molding machine. However, in the method using these single-wafer type masters, it is necessary to repeat the transfer many times in order to mass-produce the second substrate 4. When the transferability (releasability) is low, clogging occurs in the fine unevenness to be transferred, and the transfer of the fine unevenness may be incomplete. On the other hand, when the original is a web type, fine irregularities can be transferred continuously in a large area, and a necessary amount of the second substrate 4 can be produced in a short time without repeating many transfers.

Next, the original plate 40 will be described.
As shown in FIG. 8, the original plate 40 includes a base material 41 and a hard layer 42.
The hard layer 42 is a film-like layer whose surface has a concavo-convex structure that is the basis of the concavo-convex structure on the surface of the second substrate 4. The surface of the base material 41 (interface with the hard layer 42) has a concavo-convex structure following the concavo-convex structure on the surface of the hard layer 42.

As the original plate 40, there are the following types (i) (see Japanese Patent Application Laid-Open No. 2008-302591) and types (ii) (see Japanese Patent Application Laid-Open No. 2008-304701).
(I) The base material 41 is a heat-shrinkable uniaxial heat-shrinkable film made of a first resin having a glass transition temperature Tg1, and the hard layer 42 has a glass transition temperature Tg2 (where Tg2−Tg1 ≧ 10). ° C) second resin.
(Ii) The base material 41 is a heat-shrinkable uniaxial heat-shrinkable film, and the hard layer 42 is made of a metal or a metal compound.

The original plate 40 of type (i) is obtained by heating a laminate in which the second resin is laminated on a uniaxial heat-shrinkable film made of the first resin at a temperature between Tg2 and Tg1. It is done.
When the uniaxial heat-shrinkable film is thermally shrunk by heating, the heat-shrinkable uniaxial heat-shrinkable film becomes the substrate 41. The second resin is deformed so as to be folded into a hard layer 42 as the uniaxial heat-shrinkable film shrinks.
The thickness of the second resin laminated on the uniaxial heat-shrinkable film is preferably 0.05 μm to 5.0 μm.
In addition, the preferable conditions for producing the original plate 40 of the type (i) are the same as those described in Japanese Patent Application Laid-Open No. 2008-302591.

The original plate 40 of the type (ii) is obtained by heating a laminate in which a metal or a metal compound is laminated on a uniaxial heat shrinkable film.
When the uniaxial heat-shrinkable film is thermally shrunk by heating, the heat-shrinkable uniaxial heat-shrinkable film becomes the substrate 41. The metal or metal compound is deformed so as to be folded into a hard layer 42 as the uniaxial heat-shrinkable film shrinks.
The thickness of the metal or metal compound laminated on the uniaxial heat-shrinkable film is preferably 0.01 μm to 0.2 μm.
Other preferred conditions for producing the type (ii) master 40 are the same as those described in JP-A-2008-304701.

  Furthermore, in order to provide the second base material 4 with an appropriate light diffusibility that does not divide the color of the multicolored light, the concave / convex pattern 42a of the original 40 may have a large number of convex portions. Therefore, the anisotropy of the wavy uneven pattern 42a is moderately weakened by the convex portion. The apparent mode diameter of the convex part is preferably 1 μm or more and 10 μm or less, more preferably 3 μm or more and 6 μm or less, and further preferably 4 μm or more and 5 μm or less.

  In the second base material 4, as shown in FIG. 7, the incident angle from the third direction D3 perpendicular to the incident surface 4a is 0 °, and the direction approaching the upper end of the incident surface 4a from the axis A is + (positive). For example, when the incident light is incident on the incident surface 4a from 0 ° to + 70 °, the illuminance peak value of the light emitted from the inner surface of the uneven pattern 12a (that is, the output surface 4b) is set to 1. In the relative illuminance distribution curve in the first direction D1, the half value (diffusion angle) width of the relative illuminance distribution curve is 20 ° or more, and the 0.25 (¼) value (diffusion angle) width of the relative illuminance distribution curve is 30. It is preferable that it is more than °. By satisfying these conditions, the polychromatic light emitted from the first base material 2 is emitted at a wide angle in the first direction D1 (that is, the frontage direction) orthogonal to the third direction D3.

  In the daylighting sheet 1A described above, as shown in FIGS. 1 and 2, the light is emitted from a light source (not shown) such as the sun that is higher than the window and is incident on the window material W from above the axis A outside the building. The polychromatic light to be transmitted is transmitted through the window material W and the adhesive layer 8 </ b> A and is incident on the ultraviolet absorbing support 6. The ultraviolet absorbing support 6 absorbs ultraviolet rays contained in multicolor light. The light emitted from the ultraviolet absorbing support 6 passes through the adhesive layer 8B and enters the first base material 2.

  A part of the light incident on the first base material 2 is reflected by the craze region 8, is folded around the axis A, and is emitted upward from the axis A. At this time, the most frequent pitch of the craze area 8 is appropriately set as described above, and the pitch of the craze area 8 has a certain fluctuation range, so that the directivity of the multicolor light is maintained, and the color of the emitted light is changed. Dividing is reduced. The remainder of the light incident on the first substrate 2 is partially reflected by another craze region 8 and exits downward from the axis A.

  The light emitted from the first base material 2 passes through the adhesive layer 8 </ b> C and enters the second base material 4. The light incident on the second substrate 4 is diffused in the first direction D1 by the concave / convex pattern 12a, and is emitted from the emission surface 4b. When light is diffused by the second substrate 4, the most frequent pitch of the concavo-convex pattern 12 a is appropriately set as described above, and the intervals between the plurality of ridge lines composed of the vertices of the convex portions are irregular, respectively. In addition, the multi-color light is diffused in a wide angle in the second direction D2 and the color separation of the emitted light is reduced by meandering around the second direction D2. The light emitted from the second base material 4 is collected in the building.

As described above, in the daylighting sheet 1A, the first base material 2 reflects the multicolored light around the axis A with respect to the incident direction inclined in the second direction from the axis A, and the reflected light is reflected by the second base material 2A. The base material 4 can diffuse widely in the first direction D1 (rather than the diffusion angle of the first base material 2).
Therefore, according to the daylighting sheet 1A, the first direction D1 and the third direction D3 are directions parallel to the floor of the building, and the second direction D2 is a vertical direction and a direction along the surface of the window material W. The multicolor light is emitted from the window material W toward the ceiling in the + direction of the axis A in the building (that is, the ceiling direction), and at a wide angle in the first direction D1 (that is, the frontage direction). It is possible to prevent the colors of the multicolored light from being separated in the direction D2 (that is, in the vertical direction) and in the first direction D1.
As a result, sunlight incident on the window material W can be guided to the ceiling in the building that is not directly irradiated at a normal incident angle, and can be diffused light that is leveled in the frontage direction. The innermost wall surface farthest from the window side can be efficiently illuminated with reduced color separation.

  As described above, by using the material and shape of the first base material 2 and the material and shape of the second base material 4, it is possible to flexibly adhere to the shape of the window or the installation target, and so on. There is provided a daylighting sheet 1 that can be daylighted with a desired light distribution and angle in the first direction and the second direction.

  In addition, about the 2nd base material 4 of the above-mentioned lighting sheet 1A, the output surface 4b in which the uneven | corrugated pattern 12a is formed is arrange | positioned in a building, and the difference of the refractive index of the uneven | corrugated pattern 12a and an air refractive index is utilized. However, if the difference in refractive index between the material of the second base material 4 and the adhesive layer 8C can be made a predetermined value or more, the surface on which the concave / convex pattern 12a is formed is described. The adhesive layer 8 </ b> C and the second base material 4 may be bonded together so as to form the emission surface 4 b of the two base materials 4 so that the uneven pattern 12 a is embedded in the adhesive layer 8 </ b> C.

[Second Embodiment]
As shown in FIG. 9, in the daylighting sheet 1B of the second embodiment according to the present invention, the adhesive layer 8B of the daylighting sheet 1A is omitted, and a method of multilayer extrusion of the ultraviolet absorbing support 6 and the first substrate 2 is performed. The adhesive layer 8A, the ultraviolet absorbing support 6, the first base material 2, the adhesive layer 8C, and the second base material 4 are stacked in this order from the window side toward the inside of the building. It is what.
According to the daylighting sheet 1B, the same effect as the daylighting sheet 1A can be obtained. Further, since the adhesive layer 8B can be omitted, the thickness dimension of the daylighting sheet 1B can be reduced, and the manufacturing cost can be reduced.

[Third embodiment]
As shown in FIG. 10, the daylighting sheet 1C of the third embodiment according to the present invention omits the adhesive layer 8B of the daylighting sheet 1A, and includes an ultraviolet absorber instead of the adhesive layer 8A and the ultraviolet absorbing support 6. The ultraviolet absorbing adhesive layer 7 is adopted, and the ultraviolet absorbing adhesive layer 7, the first substrate 2, the adhesive layer 8C, and the second substrate 4 are arranged in this order from the window side into the building. Is.
According to the daylighting sheet 1C, the same effect as the daylighting sheet 1A can be obtained. Moreover, since the adhesive layers 8A and 8B can be omitted, the thickness dimension of the daylighting sheet 1C can be further reduced, and the manufacturing cost can be further reduced.

  As mentioned above, although embodiment which concerns on this invention was described, each embodiment is shown as an example and does not limit the range of invention. Various omissions, replacements, and changes can be made without departing from the scope of the invention.

  For example, the daylighting sheet 1 is provided on a building material other than the window material W of a building window or an appropriate member other than a building, and multicolor light is reflected back around the axis A in the second direction D2, and in the first direction D1. May be diffused over a wide angle.

  Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to the following examples.

Example 1
Example 1 relates to a daylighting sheet in which the adhesive layer 8A, the ultraviolet absorbing support 6, the adhesive layer 8B, the first base material 2, the adhesive layer 8C, and the second base material 4 are laminated in this order from the window material side.
A daylighting sheet 1A shown in FIG. 2 was produced. For the adhesive layers 8A, 8B and 8C, an optical double-sided adhesive film (manufacturer: Shin-Tac Kasei Co., Ltd.) was used, and the adhesive layers excluding the release films on both sides were used as adhesive layers 8A, 8B and 8C. As the ultraviolet absorbing support 6, a soft type weather resistant film (manufacturer: Mitsubishi Rayon Co., Ltd.) mainly composed of polymethyl methacrylate resin was used. As the first base material 2, a monotran film (manufacturer: NAC Co., Ltd.) was used. In general, the thickness dimension of a monotran film is 50 μm to 200 μm, and porous portions having a width of 4 μm to 10 μm are formed at intervals of 20 μm to 30 μm. In the present embodiment, the porous portions are formed at intervals of 10 μm to 30 μm.

The light distribution in the second direction D2 of the used monotran film (that is, the first substrate 2) was measured by the optical arrangement shown in FIG.
According to the graph of the light distribution for each incident angle shown in FIG. 12A, the light intensity peak of the emitted light also increases in the + direction as the incident angle with respect to the axis A shown in FIG. 12B increases in the + direction. It can be seen that white light is emitted in the second direction D2 (that is, the ceiling direction).

  In the optical arrangement shown in FIG. 11 (a), measurement was performed by moving the light receiver S with respect to the monotran film as shown in FIG. 11 (b).

  Hereinafter, for the total light transmittance, using a haze meter (model number: HM-150, manufacturer: Murakami Color Research Laboratory), the light of the standard D65 light source defined by the International Lighting Commission (CIE) is used as the first base material 2. It was made to enter into the entrance plane 2a, and obtained by measuring with visible light (wavelength: 380 nm to 800 nm) by the method prescribed | regulated to JISK7361. In the monotran film used in this example, the total light transmittance was an average of 91.6%, a maximum of 91.7%, and a minimum of 91.3%.

Moreover, about parallel light transmittance, using the haze meter (model number; HM-150, manufacturer: Murakami Color Research Laboratory), the light of the standard D65 light source of International Lighting Commission (CIE) regulation is used for the 1st base material 2. It was made to enter into the entrance plane 2a, and obtained by measuring with visible light (wavelength: 380 nm to 800 nm) by the method prescribed | regulated to JISK7361. In the monotran film used in this example, the average parallel light transmittance was 71.1%, the maximum was 71.7%, and the minimum was 70.0%.
For the diffuse light transmittance, a haze meter (model number: HM-150, manufacturer: Murakami Color Research Laboratory) is used, and the light of the standard D65 light source defined by the International Lighting Commission (CIE) is used as the first base material 2. It was made to enter into the entrance plane 2a, and obtained by measuring with visible light (wavelength: 380 nm to 800 nm) by the method prescribed | regulated to JISK7361. In the monotran film used in this example, the diffuse light transmittance was 20.5% on average, 21.7% at the maximum, and 19.8% at the minimum.

  Further, for haze, a haze meter (model number: HM-150, manufacturer: Murakami Color Research Laboratory) is used, and the light from the standard D65 light source defined by the International Lighting Commission (CIE) is used as the incident surface 2a of the first substrate 2. And measured by visible light (wavelength: 380 nm to 800 nm) by a method defined in JIS K7136. In the monotran film used in this example, the haze averaged 22.4%, maximum 23.7%, and minimum 21.7%.

Next, an LED light source having an irradiation angle of 3.5 degrees (that is, light source T) is arranged at a position 50 mm away from the base material on one side (for example, the incident surface 2a) side of the first base material 2, and from the light source The light was incident so that the optical axis with the highest emission luminance was at a predetermined incident angle with respect to the incident surface 2a of the first substrate 2. The transmitted and scattered light at that time was measured using a goniometer GENESISA (registered trademark) Gonio / FFP (manufacturer: Genesia) to obtain an illuminance curve shown in FIG.
Here, the illuminance curve refers to a plotted curve with the horizontal axis as the incident light angle and the vertical axis as the outgoing light illuminance rate. Specifically, the illuminance of light emitted from the first base material 2 with a peak at a predetermined angle is along a direction orthogonal to the longitudinal direction of the crazing region 8 of the first base material 2 (that is, the second direction D2). The light emission angle was measured at intervals of 1 ° from -90 ° to 90 ° to obtain an illuminance curve.
Then, the 1st base material 2 was abbreviate | omitted and it measured similarly to the above-mentioned method, and obtained the illumination intensity curve of the original light source, and the integrated illumination intensity (original light quantity) from -90 degrees to 90 degrees of light emission angles.
Next, among the illuminances measured at intervals of 1 ° from −90 ° to 90 ° of the illuminance curve on the incidence, an integrated value of illuminance measured at 1 ° intervals from 0 ° to 90 ° is obtained, and the first base material is obtained. The ratio with respect to the integrated illuminance value of the original light source measured at intervals of 1 ° from −90 ° to 90 ° obtained without 2 was obtained as the reflected light emission ratio.

  Further, according to the graph shown in FIG. 13, the output ratio of the first base material 2 in the positive direction of the axis A is, for example, 30% or more when the incident angle is between + 25 ° and + 55 °. It can be seen that the emission ratio in the + direction becomes 25% or more, for example, when the incident angle is between + 20 ° and + 60 °.

An LED light source (ie, light source T) with an irradiation angle of 3.5 degrees is arranged at a position 50 mm away from the base material on one side (for example, the incident surface 2a) side of the first base material 2, and the light is most emitted. Light was incident so that the optical axis at which the luminance was increased was at an incident angle with respect to the incident surface 2 a of the first base material 2.
An illuminance curve was obtained by measuring the transmitted and scattered light at that time using a goniometer GENESISA (registered trademark) Gonio / FFP (manufacturer: Genesia).
Specifically, the illuminance of light emitted from the first base material 2 with a peak at a certain angle is set to a light output angle of −90 ° to 90 ° along a direction orthogonal to the longitudinal direction of the crazing region 8 of the first base material 2. The illuminance curve was obtained by measuring at intervals of 1 °.
Next, the reflected light illuminance integrated value within the range of the reflected light emission peak value ± 20 ° is obtained for each incident angle, and the ratio to the integrated illuminance value of the reflected light emission range of 0 ° to 90 ° is obtained to obtain the reflected light distribution range. . Similarly, the reflected light illuminance integrated value in the range of the reflected light emission peak value ± 10 ° was obtained and set as the light distribution range of the reflected light.

  From the graph shown in FIG. 14, the emission light amount in the + direction of the axis A of the first base material 2 decreases as the incident angle of the polychromatic light increases for the light emission peak of ± 10 °, When the emitted light amount peak is expanded to ± 20 °, the emitted light amount in the + direction of the axis A of the first base material 2 is extremely good at 100%.

An LED light source (ie, light source T) with an irradiation angle of 3.5 degrees is arranged at a position 50 mm away from the base material on one side (for example, the incident surface 2a) side of the first base material 2, and the light is most emitted. Light was incident so that the optical axis for increasing the brightness was at a predetermined incident angle with respect to the incident surface 2 a of the first base material 2.
An illuminance curve was obtained by measuring the transmitted and scattered light at that time using a goniometer GENESISA (registered trademark) Gonio / FFP (manufactured by Genesia).
Specifically, the illuminance of light emitted from the first base material 2 with a peak at a certain angle is along a direction orthogonal to the longitudinal direction of the crazing region 8 of the first base material 2 (that is, the second direction D2). The illuminance curve was obtained by measuring the light emission angle from -90 ° to 90 ° at 1 ° intervals.

  Next, among the total amount of light emitted from the first base material 2, an integrated illuminance value obtained by measuring at an interval of 1 ° from an output angle of 0 ° to 90 ° is obtained, and the reflected light illuminance with respect to the integrated total output light illuminance value The result of obtaining the ratio of the integrated value is shown in FIG.

A nano buckling sheet (33 ° / 3 °, manufacturer: Oji Holdings Corporation) was used as the second base material 4 of the daylighting sheet 1A of this example. This nano buckling sheet is manufactured by the manufacturing method described below.
First, a heat shrinkable film made of polyethylene terephthalate with a thickness of 50 μm and a Young's modulus of 3 GPa (model number: HIPSETTE LX-60S, manufacturer: Mitsubishi Plastics, glass transition temperature Tg1: 70 ° C.) Polymethylmethacrylate diluted in toluene (model number: P4831-MMA, manufacturer: Polymer Source Co., Ltd., glass transition temperature Tg2: 100 ° C.) is coated with a bar coater to a thickness of 200 nm to form a hard layer. To obtain a laminated sheet.
Next, the laminated sheet is heated at 150 ° C. for 1 minute using a general hot air oven to heat-shrink the polyethylene terephthalate uniaxial heat-shrinkable film to 40% of the length before heating in the uniaxial direction. (The deformation rate was 60%), and the hard layer was deformed so as to be folded. Thereby, the surface fine uneven sheet | seat (original) in which the fine unevenness | corrugation which has a wavy uneven pattern and many convex parts formed on it was formed in the surface of the hard layer was obtained.
Next, transfer was performed as follows using the obtained uneven pattern forming sheet as an original plate. That is, the surface on which the concave / convex pattern forming sheet was formed was subjected to nickel plating, and the nickel plating was peeled off to obtain a secondary process sheet having a thickness of 200 μm. An uncured ultraviolet curable resin composition containing an epoxy acrylate prepolymer, 2-ethylhexyl acrylate and a benzophenone photopolymerization initiator was applied to the surface of the secondary process sheet on which the concavo-convex pattern was formed.
Next, 50 μm-thick polyethylene terephthalate (PET) was superimposed and pressed on the surface of the coating film of the uncured ultraviolet curable resin composition that was not in contact with the secondary process sheet. Subsequently, ultraviolet rays were irradiated from above the polyethylene terephthalate film to cure the uncured ultraviolet curable resin composition, and the cured product was peeled from the secondary process sheet to obtain a light diffuser. This light diffuser is composed of two layers (PET layer and resin layer cured by ultraviolet rays).

  The aspect ratio of the uneven pattern 12a of the nano buckling sheet used was 0.6.

An LED light source with an irradiation angle of 3.5 degrees (i.e., light source T) is arranged at a position 50 mm away from the substrate on the side of the second substrate 4 where the uneven pattern 12a is not provided (i.e., the incident surface 4a), The light was incident so that the optical axis with the highest luminance was perpendicular to the substrate surface.
An illuminance curve was obtained by measuring the transmitted and scattered light at that time using a goniometer GENESISA (registered trademark) Gonio / FFP (manufacturer: Genesia). The illuminance curve is a plotted curve with the horizontal axis as the light emission angle and the vertical axis as the relative illuminance.
Specifically, the relative illuminance when the illuminance of light emitted perpendicularly from the second base material (also referred to as an anisotropic light diffusion sheet) (the light emission angle of this light is 0 °) is set to 1 is an uneven pattern. An illuminance curve was obtained by measuring at an interval of 1 ° from a light emission angle of −90 ° to 90 ° along a direction perpendicular to the longitudinal direction.
0.5 value width (light emission angle range in which relative illuminance is ½ or more) and 0.25 value width (light emission angle range in which relative illuminance is ¼ or more) in a direction orthogonal to the longitudinal direction of the uneven pattern. These were determined as the diffusion angles.
Next, the incident angle is changed in increments of 10 °, and in the same manner as described above, 0.5 value (light emission angle range where the relative illuminance becomes 1/2 or more) and 0.25 value width (relative illuminance becomes 1/4 or more). The light emission angle range is determined as a change in each diffusion angle depending on the incident angle.

  According to the graph shown in FIG. 16, even if the incident angle of light in the first direction D1 with respect to the axis A varies between 0 ° and 90 °, the diffusion angle in the first direction D1 is relatively stable. You can see that

(Example 2)
Except for changing the second base material 4 of the daylighting sheet 1A of Example 1 to a nano buckling sheet (20 ° / 10 °, manufacturer: Oji Holdings Co., Ltd.) described below, it was the same as Example 1. . The nano buckling sheet of this example is manufactured by the manufacturing method described below.
First, the following coating liquid (1) is applied to one side of a polyethylene terephthalate (PET) uniaxial heat shrinkable film (“SC807”, thickness: 30 μm, glass transition temperature Tg1 = 80 ° C., manufacturer: manufactured by Toyobo Co., Ltd.). The coating was performed by a bar coater (Meyer bar # 14) so that the thickness of the hard layer after drying was 2 μm.

[Coating fluid (1)]
Acrylic resin A (glass transition temperature Tg2 = 128 ° C.) and acrylic cross-linked resin particles having a particle size of 5 μm (“SSX105”, Vicat softening temperature of 200 ° C. or higher, manufacturer: Sekisui Plastics Co., Ltd.) The mixture was mixed at a solid content mass ratio of 70:30, and in addition to toluene, a coating solution (1) having a solid content concentration of 7.7 mass% was obtained.
In addition, although the above-mentioned acrylic resin A is 20 mass% of solid content concentration, the mass ratio and density | concentration in a present Example are the values calculated by the net amount (solid content amount). The following examples are also calculated with the net amount.

  Next, the laminated sheet is heated at 150 ° C. for 1 minute using a general hot air oven to heat-shrink the polyethylene terephthalate uniaxial heat-shrinkable film to 49% of the length before heating in the uniaxial direction. (The deformation rate was 51%), and the hard layer was deformed so as to be folded. Thereby, the surface fine uneven sheet | seat (original) in which the fine unevenness | corrugation which has a wavy uneven pattern and many convex parts formed on it was formed in the surface of the hard layer was obtained. Each of the formed ridges meandered and was irregularly formed in parallel with each other.

  Next, nickel was deposited to a thickness of 500 μm on the surface of the obtained surface fine concavo-convex sheet (that is, the original plate) by nickel electroforming. Subsequently, the deposited nickel was peeled from the surface fine uneven sheet, and a nickel secondary original plate having the surface fine unevenness transferred on the surface was obtained. The nickel secondary master was incorporated into a mold of an injection molding machine, and injection molding of an acrylic resin was performed to obtain an injection molded product having fine irregularities transferred on the surface. The obtained injection-molded product is a rectangular parallelepiped of 300 mm × 10 mm × 2 mm, in which fine irregularities are transferred to one surface of a pair of 2 mm × 300 mm surfaces, and the other surface is a smooth surface.

  In addition, about the aspect ratio of the uneven | corrugated pattern 12a of the nano buckling sheet | seat in a present Example, although the same suitable conditions as Example 1 were considered, the acrylic resin A, an acrylic bridge | crosslinking type resin particle, etc. are used. Therefore, quantification is difficult.

(Comparative Example 1)
A daylighting sheet of Comparative Example 1 was produced in the same manner as in Example 1 except that the second base material 4 of the daylighting sheet 1A of Example 1 was changed to a commercially available lenticular lens sheet.

(Comparative Example 2)
The daylighting sheet of Comparative Example 2 was obtained by using only the first base material 2 of the daylighting sheet 1A of Example 1 (that is, monotran film (manufacturer: NAC Co., Ltd.)).

(Comparative Example 3)
Only the second base material 4 of the daylighting sheet 1A of Example 1 (that is, a nano buckling sheet (33 ° / 3 °, manufacturer: Oji Holdings Corporation)) was used as the daylighting sheet of Comparative Example 3.

(Comparative Example 4)
Only the second base material 4 (that is, the nano buckling sheet (20 ° / 10 °, manufacturer: Oji Holdings Corporation)) of the daylighting sheet 1A of Example 2 was used as the daylighting sheet of Comparative Example 4.

(Comparative Example 5)
The first base material 2 of the daylighting sheet 1A of Example 1 was not used, and the second base material 4 was changed to a commercially available lenticular lens sheet to obtain a daylighting sheet of Comparative Example 5.

(Comparative Example 6)
The window material W and the daylighting sheet shown in FIGS. 17A and 17B and FIGS. 18A and 18B were not provided, and only windows were used.

  In each of Examples 1 and 2 and Comparative Examples 1 to 6 described above, the optical arrangement and model shown in FIGS. 17A and 17B and FIGS. As shown below, the illuminance was measured at the position shown in FIG.

<Evaluation of illuminance>
Each of the daylighting sheets of Examples 1 and 2 and Comparative Examples 1 to 6 was installed in a window, and as shown in FIG. 19, a “ceiling surface (center part)” was directly above the window at a position of 225 mm from the window. The illuminance (lux) at the center of the ceiling surface that corresponds to the "backmost wall surface (left end)" and "backmost wall surface (right end)". The illuminance (lux) at a position of 150 mm was measured.
As shown in FIG. 12 (b), the daylighting sheets of the examples and the comparative examples were arranged inside the building of the opening X of the wall surface B standing upright from the floor F. As the light source T, a spot type LED light (model number: NLSM05S-AC, manufacturer: Nikki Co., Ltd.) was used. From the light source T, white light (polychromatic light) with a 1-m illuminance 1570 lux and a total luminous flux of 280 lm was incident on the daylighting sheet while changing the incident angle from 0 ° to + 60 ° at intervals of 20 °. Moreover, about the light radiate | emitted from the lighting sheet, it measured using the digital illuminometer (model number: IM-600, manufacturer: Topcon Techno House Co., Ltd.) as the light-receiving part S. FIG.

<Evaluation of daylighting rate>
With respect to the outdoor side surface of the window in which the daylighting sheets of Examples 1 and 2 and Comparative Examples 1 to 6 are not installed, the light is “elevation angle 45 ° / azimuth angle 180 °” and “elevation angle 45 ° / The illuminance of light (the illuminance is used as a reference illuminance) when the incident light is changed into an azimuth angle of 225 ° and an elevation angle of 0 ° / 180 ° was measured with an illuminometer. The ratio of the illuminance of light when each daylighting sheet was installed in a window to the measured reference illuminance was measured as “lighting rate”.

<Evaluation of luminance unevenness>
The daylighting sheets of Example 1, Example 2 and Comparative Example 1 provided with the daylighting sheet according to the present invention were installed in a window, and the light was “elevation angle 45 ° / azimuth angle 225 ° with respect to the surface on the outdoor side of the window. The brightness unevenness of the innermost wall surface when it was incident was visually evaluated.

  Table 1 shows the results of measuring the emitted light quantity and the reflected light emission ratio under each incident condition of an elevation angle of 45 ° and an azimuth angle of 225 °.

  As can be seen from Table 1, the illuminance and the lighting rate of the daylighting sheets of Example 1 and Example 2 are much larger than the illuminance and the daylighting rate of Comparative Examples 4 and 5, and further the illuminance of the daylighting sheet of Comparative Example 6 And larger than the daylighting rate. Thereby, in the daylighting sheet 1A, it is considered that the light is reflected by being folded around the axis A, and is well-lighted. In addition, in the daylighting sheets of Example 1 and Example 2, it was confirmed that the daylighting rate exceeded 200% over the ceiling surface (center part) and the innermost wall surface (left end part and right end part), and the lighting was performed well. did.

  Regarding the evaluation of luminance unevenness, there is a large difference in the amount of emitted light and the reflected light emission ratio between the daylighting sheets of Example 1 and Example 2 and the daylighting sheet of Comparative Example 1 including a lenticular lens sheet. Although not seen, in the daylighting sheet of Comparative Example 1, the color separation of the light collected in the first direction D1 was visually recognized. Such color separation is attributed to the periodic structure of the lenticular lens sheet, and is because light for each wavelength is diffracted and diffracted in different directions (ie, emission angles).

  According to the embodiments and comparative examples described above, according to the present invention, if the first direction D1 is a direction parallel to the floor of the building and the second direction D2 is a direction perpendicular to the floor of the building, windows and windows The sunlight incident on the material W can be guided to the ceiling in the building that is not directly irradiated at the normal incident angle, and can be diffused light that is leveled in the frontage direction, and is the farthest from the ceiling surface and the window side in the building It was confirmed that a daylighting sheet that efficiently illuminates the innermost wall surface and the like and suppresses color separation can be realized.

1, 1A, 1B, 1C ... Daylighting sheet 2 ... 1st base material 4 ... 2nd base material 8 ... Craze area | region 10 ... Uneven | corrugated pattern formation sheet D1 ... 1st direction D2 ... Second direction W ... Window material

Claims (6)

A daylighting sheet in which a first base material and a second base material are arranged to overlap,
Inside the first base material, a craze region consisting of molecular bundles and micropores and extending in a stripe shape along the first direction is formed,
In the second base material, irregularities are repeated along the first direction, and each of the plurality of ridge lines composed of vertices of the convex portions of the irregularities is irregularly spaced in the first direction. A daylighting sheet in which a wavy uneven pattern meandering in the intersecting second direction is formed. Placed in the window or opening of the building,
The first direction is a direction parallel to the floor of the building,
The daylighting sheet according to claim 1, wherein the second direction is a direction perpendicular to a floor surface of the building.   The daylighting sheet according to claim 1 or 2, wherein the most frequent pitch of the craze region is 1 µm or more and 30 µm or less.   The daylighting sheet according to any one of claims 1 to 3, wherein the most frequent pitch of the concavo-convex pattern is 1 µm or more and 30 µm or less. The second substrate is
A resin base material;
A resinous light diffusion layer provided on one side of the base material,
The daylighting sheet according to any one of claims 1 to 4, which is a concavo-convex pattern forming sheet in which the concavo-convex pattern is formed on a surface of the light diffusion layer.   A daylighting apparatus comprising the daylighting sheet according to any one of claims 1 to 5.

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