JPWO2016195054A1 - Daylighting member - Google Patents

Abstract

The main object is to provide a daylighting member capable of exhibiting both functions of high privacy concealment and high daylighting. An incident surface that is a surface on which light is incident, an exit surface that is a surface on which light is emitted and is opposed to the incident surface, and the incident surface is disposed between the incident surface and the exit surface. A lighting member having at least a plurality of light reflecting surfaces for reflecting light incident from the surface toward the emitting surface, wherein the lighting member has a total light transmittance of 80% or more and the incident light. The intensity of the emitted light that is incident from the surface at an incident angle of 20 ° or more and 60 ° or less and is emitted from the emission surface is measured, and the emission angle at which the intensity of the emitted light corresponding to each incident angle is maximized And the intensity of the outgoing light within the range of the outgoing angle ± 3 ° when the maximum peak intensity of the outgoing light at the outgoing angle is 100% is 40% or more. A daylighting member is provided.

Description

  The present invention relates to a daylighting member having both functions of high privacy concealment and high daylighting.

In recent years, as environmental problems such as global warming become more serious, for the purpose of energy saving and CO ₂ reduction, the daylighting member that controls the absorption of incident light by adjusting the absorption, deflection, reflection, transmission, etc. of external light Is being developed and used.

  For example, a daylighting member having a function of reflecting or refracting visible light takes in light from the outside by jumping up the light incident from the outside and guiding it upward (ceiling) where the incident light is difficult to reach. The amount (light collection amount) can be increased, and the captured light can be effectively used as indirect lighting in the room. In this way, by using the daylighting function of the daylighting member, it is possible to reduce the use time of indoor lighting and power consumption.

In Patent Document 1, as a daylighting member, a first surface, a second surface facing the first surface, and a plurality of elements arranged in a region defined by the first surface and the second surface are arranged. There is disclosed a structural layer designed so that the shape of the reflecting surface satisfies a predetermined relationship with the arrangement pitch and the incident angle of incident light. Since the structure layer has the above-described structure, light incident at a predetermined angle can be efficiently emitted in a predetermined angle range, and high daylighting performance can be obtained.
In Patent Document 1, a light transmission layer (light diffusing layer) having a light diffusing element having a periodic or aperiodic shape such as a prism sheet is disposed on the surface of the structure layer, so that incident light is directed upward. A technique is disclosed that extends the effective irradiation range of emitted light by emitting light toward the outside and diffusing light in the lateral direction.

  In addition, the study of daylighting members having an additional function in addition to the daylighting function is also proceeding. For example, a light-transmitting daylighting building material in which a light diffusion layer disclosed in Patent Document 2 is arranged increases the amount of daylighting. At the same time, by diffusing light by the light diffusing layer, it is possible to exhibit an anti-glare function for controlling light reaching directly to human eyes.

JP 2012-38626 A JP 2009-275456 A

By the way, in order to increase the light intensity of the daylighting member, it is necessary to increase the light transmittance of the daylighting member and increase the light receiving area of the daylighting member. Is easily visible, and it is difficult to ensure privacy concealment.
In general, as a method of exhibiting the privacy hiding function, for example, there is a method of increasing the haze value by diffusing light by roughening the surface of the daylighting member or providing a light diffusion layer. However, if the surface of the daylighting member is simply roughened or a light diffusion layer is provided, for example, light is scattered backward in the incident direction in the process of passing through the daylighting member, and the amount of emitted light decreases with respect to the amount of incident light. In addition, there is a problem that high daylighting performance cannot be obtained because light more than the amount necessary for exhibiting the privacy hiding function is diffused and the intensity of light contributing to improvement in illuminance is reduced.
Thus, it is not easy for the daylighting member to achieve both high privacy concealment and high daylighting.

  Patent Documents 1 and 2 disclose that a light diffusing layer is provided on a daylighting member, thereby enabling the function of adjusting the effective irradiation area of the emitted light and the antiglare function to be exhibited. It is not intended to add a privacy hiding function to the above and to enable the daylighting member to exhibit both functions of high privacy hiding and high daylighting. Further, these documents do not disclose a technique for efficiently performing both functions.

  The present invention has been made in view of the above circumstances, and a main object thereof is to provide a daylighting member capable of exhibiting both functions of high privacy concealment and high daylighting.

  As a result of intensive studies by the present inventors in order to solve the above-mentioned problems, it is possible to exhibit both functions of high privacy concealment and high daylighting by defining specific optical characteristics of the daylighting member. Found that is possible.

That is, the present invention includes an incident surface that is a surface on which light is incident, an exit surface that is a surface on which light is emitted and is opposed to the incident surface, and a space between the incident surface and the exit surface. A plurality of light reflecting surfaces that are arranged so as to intersect the incident surface and the exit surface and reflect light incident from the entrance surface toward the exit surface, The daylighting member has a total light transmittance of 80% or more, and measures the intensity of outgoing light emitted from the outgoing surface by entering light at an incident angle of 20 ° to 60 ° from the incident surface, A range of the emission angle ± 3 ° when the emission angle at which the intensity of the emission light corresponding to each incident angle is maximum is specified and the maximum peak intensity of the emission light at the emission angle is 100%. The intensity of the emitted light inside is 40% or more. Providing a lighting member, characterized in that it.
As for the light reflecting surface, “arranged between the incident surface and the exit surface so as to intersect the incident surface and the exit surface” means “disposed between the incident surface and the exit surface”. In other words.

According to the present invention, the daylighting member has both the translucency defined by the total light transmittance and the light diffusivity defined by the emitted light intensity within the range of the predetermined emission angle. Both the high privacy concealment property by light diffusion and the high daylighting property by light transmission can be exhibited.
Note that the above-described translucency and light diffusibility of the daylighting member of the present invention may be collectively referred to as “optical characteristics of the daylighting member”.

In the above invention, the daylighting member is a daylighting film having a light control layer and a light diffusion layer disposed on one surface side of the light control layer, and the light control layer is made of a transparent resin. A light transmitting portion configured, a plurality of groove portions formed on one surface of the light transmitting portion in a direction intersecting the light incident surface and the light emitting surface, and formed in the plurality of groove portions; It is preferable to have a light deflecting unit that has a refractive index different from that of the transmitting unit. In addition, “a plurality of grooves formed on one surface of the light transmitting portion in a direction intersecting with the light incident surface and the light emitting surface” is “formed on one surface of the light transmitting portion, In other words, “a plurality of grooves having the light reflecting surface”.
By using the daylighting member of the present invention as the daylighting film having the above-described configuration, the interface between the light transmission part and the light deflection part in the light control layer becomes a light reflection surface, and light is splashed by the light reflection surface. This is because the amount of light collected can be increased. Further, since light is diffused by the light diffusion layer, high privacy concealment can be exhibited in the entire daylighting film. Furthermore, by setting it as the daylighting film which has the above-mentioned structure, it becomes easy to install in desired positions, such as a window glass, and it becomes easy to show | play the effect of this invention.

  In the above invention, it is preferable that the light diffusion layer is located closer to the light exit surface than the light control layer. By making light enter the light control layer before the light diffusion layer, more light can be reflected, and by diffusing the reflected light by the light diffusion layer, high privacy concealment by light diffusion and This is because both functions of high daylighting due to light transmission can be more effectively exhibited.

  In the said invention, it is preferable that the base material layer is arrange | positioned on one surface of the said light control layer, and the said light-diffusion layer is integral with the said base material layer. This is because a single layer of the base material layer can exhibit the function of supporting the light control layer and the function of imparting desired optical properties to the entire daylighting film.

In the above invention, the daylighting member has the first glass layer, the first sealing portion, the light control layer, the second sealing portion, and the second glass layer in this order, A laminated glass having a light diffusion layer disposed on one surface of the first glass layer or the second glass layer, wherein the light control layer includes a light transmission portion made of a transparent resin, and the light A plurality of grooves formed in a direction intersecting the light incident surface and the light exit surface on one surface of the transmission portion, and light deflection formed in the plurality of groove portions and having a refractive index different from that of the light transmission portion. Part. In addition, “a plurality of grooves formed on one surface of the light transmitting portion in a direction intersecting with the light incident surface and the light emitting surface” is “formed on one surface of the light transmitting portion, In other words, “a plurality of grooves having the light reflecting surface”.
By making the daylighting member of the present invention a laminated glass having the above-described configuration, the interface between the light transmitting portion and the light deflecting portion in the light control layer becomes a light reflecting surface, and the light is reflected by the light reflecting surface. This is because the amount of light collected can be increased. Moreover, since light is diffused by the light diffusion layer, high privacy concealment can be exhibited in the entire laminated glass. Furthermore, by setting it as the laminated glass which has the above-mentioned structure, it becomes easy to install in desired places, such as an opening part, and it becomes easy to show | play the effect of this invention.

  In the above invention, it is preferable that the light diffusion layer is located closer to the light exit surface than the light control layer. By making light enter the light control layer before the light diffusion layer, more light can be reflected, and by diffusing the reflected light by the light diffusion layer, high privacy concealment by light diffusion and This is because both functions of high daylighting due to light transmission can be more effectively exhibited.

  In the said invention, it is preferable that the said light-diffusion layer is integral with the said 1st glass layer or the said 2nd glass layer. This is because the function of supporting the light control layer and the function of imparting desired optical properties to the entire laminated glass can be exhibited by a single layer of the first glass layer or the second glass layer.

  According to the present invention, since it has the predetermined optical characteristics defined by the total light transmittance and the intensity of the emitted light within the range of the predetermined emission angle, it is possible to provide a daylighting member having high privacy concealment and daylighting performance. There is an effect that can be done.

It is a schematic diagram which shows an example of the lighting member of this invention. It is explanatory drawing explaining the prescription | regulation method of the light diffusivity of the lighting member of this invention. It is a schematic diagram which shows the example of the shape of the light reflection surface in the lighting member of this invention. It is a schematic sectional drawing which shows the other example of the lighting member of this invention. It is a schematic sectional drawing which shows the other example of the lighting member of this invention. It is a schematic sectional drawing which shows the other example of the lighting member of this invention. It is a schematic sectional drawing which shows the other example of the lighting member of this invention. It is a schematic sectional drawing which shows an example of the light control layer in the lighting member of this invention. It is a schematic sectional drawing which shows the other example of the lighting member of this invention. It is a schematic sectional drawing which shows the other example of the lighting member of this invention. It is a picked-up image of privacy hiding property evaluation in an Example and a comparative example. It is a picked-up image of privacy hiding property evaluation in an Example and a comparative example.

Hereinafter, the daylighting member of the present invention will be described in detail.
The daylighting member of the present invention includes an incident surface that is a surface on which light is incident, an exit surface that is a surface on which light is emitted and faces the incident surface, the incident surface, and the exit surface. A lighting member that has at least a plurality of light reflecting surfaces that are arranged so as to intersect the incident surface and the emitting surface and reflect light incident from the incident surface toward the emitting surface, The daylighting member has a total light transmittance of 80% or more, and measures the intensity of outgoing light emitted from the outgoing surface by entering light at an incident angle of 20 ° to 60 ° from the incident surface. The emission angle at which the intensity of the emitted light corresponding to each incident angle is maximized is specified, and the emission angle is ± 3 ° when the maximum peak intensity of the emitted light at the emission angle is 100%. The intensity of the emitted light within the range is 40% or more. And characterized in that.

The daylighting member of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing an example of a daylighting member of the present invention. Moreover, FIG. 2 is explanatory drawing explaining the prescription | regulation method of the light diffusivity of the lighting member of this invention.
As shown in FIG. 1, the daylighting member 10 of the present invention is an incident surface 1 that is a surface on which light is incident, a surface that emits light, and a surface that faces the incident surface 1. A plurality of light reflections arranged between the exit surface 2 and the entrance surface 1 and the exit surface 2 so as to intersect the entrance surface 1 and the exit surface 2 and reflect the light incident from the entrance surface 1 toward the exit surface 2 And at least a surface 3. In the daylighting member 10 illustrated in FIG. 1, a plurality of light deflecting units 4 each having a light reflecting surface 3 are arranged between an incident surface 1 and an exit surface 2, and the air between adjacent light deflecting units 4 serves as a light transmitting unit. In this embodiment, the layer 5 is used.
The daylighting member 10 has desired translucency and light diffusibility. Here, the desired translucency of the daylighting member 10 means that the total light transmittance is 80% or more.
The desired light diffusing the lighting member 10 has, incident light L _in at a predetermined incident angle theta _in from the entrance surface 1 of 20 ° to 60 ° of the optical member 10 as shown in FIGS. 1 and 2 Then, the intensity I _out of the outgoing light L _out emitted from the outgoing surface 2 is measured. At this time, the intensity _{I out} of exiting light _{L out} corresponding to each incident angle theta _in the identify emission angle theta _OUTMAX which maximizes the maximum peak intensity _{I OUTMAX} of the outgoing light _{L out} on the emission angle theta _OUTMAX 100 It means that the intensity I _out of the outgoing light L _out within the range of the outgoing angle θ _outMax ± 3 ° is 40% or more.
The incident angle θ _in is defined by an angle (polar angle) formed by the light source with respect to the axis X with the axis X in the normal direction to the incident surface 1. Further, the emission angle θ _out is defined by an angle (polar angle) formed with the axis X in the normal direction to the emission surface 2 and the emission light L _out with respect to the axis X.

  According to the present invention, the daylighting member has both the translucency defined by the total light transmittance and the light diffusivity defined by the emitted light intensity within the range of the predetermined emission angle. When the other space is viewed from one space through the daylighting member, the state of both spaces is less visible. At the same time, the amount of light incident through the daylighting member can be increased, and more light can be jumped up at a desired angle. Thereby, the daylighting member of the present invention can exhibit both functions of high privacy concealment by light diffusion and high daylighting by light transmission.

  In the present invention, light and light rays are visible light having a wavelength range of 380 nm to 780 nm unless otherwise specified.

  Hereinafter, the daylighting member of the present invention will be described by dividing it into optical characteristics and aspects of the daylighting member.

I. Optical characteristics The daylighting member of the present invention has desired light-transmitting properties and light-diffusing properties.

A. Translucency The daylighting member of the present invention exhibits a total light transmittance of 80% or more in the whole daylighting member regardless of the aspect of the daylighting member described later.
The total light transmittance of the entire daylighting member is an index indicating the proportion of light emitted from the exit surface among the light incident from the entrance surface of the daylighting member. In addition, the higher the total light transmittance, the more light is scattered forward by the daylighting member. For this reason, the higher the total light transmittance, the greater the amount of light emitted from the exit surface, and the higher daylighting performance can be achieved. Among them, the daylighting member of the present invention preferably has a total light transmittance of 80% or more, particularly 85% or more. If the total light transmittance is smaller than the above range, the light incident on the daylighting member is scattered back, or the light is absorbed into the daylighting member, and the amount of light emitted from the emission surface side is reduced, thereby exhibiting a high daylighting function. This is because it may become impossible.
In the present invention, the total light transmittance is a value calculated using a haze meter HR100 (manufactured by Murakami Color Research Laboratory, JIS K7361: 1999 compliant method).

B. Light diffusivity The daylighting member of the present invention is an outgoing light that is incident from the incident surface of the daylighting member at an incident angle of 20 ° to 60 ° and emitted from the outgoing surface regardless of the aspect of the daylighting member described later. The intensity at which the intensity of the emitted light corresponding to each incident angle is maximized is determined, and the maximum peak intensity of the emitted light at the identified emitted angle is 100%. The intensity of the outgoing light within the range of the outgoing angle ± 3 ° (hereinafter simply referred to as “converted intensity of outgoing light within the range of the outgoing angle ± 3 ° indicating the maximum peak intensity for each incident angle”). That is 40% or more. Among these, the strength is preferably 40% or more, particularly 48% or more. Moreover, although the said intensity | strength is so preferable that it is high, it is preferable that it is 90% or less.
In this invention, the conversion intensity | strength of the emitted light which exists in the range of the emission angle +/- 3 degree which shows the maximum peak intensity | strength for every incident angle was forward-scattered and radiate | emitted out of the light which injected into the lighting member at each incident angle. It becomes an index representing the degree of light spread (light diffusibility). For this reason, the higher the intensity, the higher privacy concealment due to the diffusion of light within the desired region. Moreover, since the attenuation of the amount of light and intensity | strength by spreading | diffusion of an excessive amount of light can be suppressed, the fall of a lighting function can be prevented.
On the other hand, if the converted intensity of the emitted light within the range of the emission angle ± 3 ° indicating the maximum peak intensity for each incident angle in the entire daylighting member is lower than the above range, the light is not diffused and privacy concealment is ensured. There are cases in which the effect of glare due to the inability to do so or the direct arrival of emitted light to the human eye is increased.

The above-mentioned parameters defining the light diffusibility of the daylighting member are measured by the following method.
First, a three-dimensional variable angle spectrocolorimetry system (GCMS11 manufactured by Murakami Color Research Laboratory Co., Ltd.) is used as the measurement device, and the light source is positioned on the incident surface side and the light receiver is positioned on the output surface side. The daylighting member of the present invention is fixed. The measurement device settings are as follows.
Measurement mode: Transmission measurement mode Incident angle: 20 ° to 60 ° (incident angle of light with respect to the normal direction of the incident surface)
Light reception angle: within a range of −70 ° to + 70 ° (light emission angle with respect to the normal direction of the emission surface)
・ Light source: D65
・ Field of view: 2 °
・ Measurement area: about φ3mm at 0 ° light reception angle, about 3mm × 13.3mm at 77 ° light reception angle (ellipse)
Next, light is irradiated at a predetermined incident angle from the light source to the incident surface of the daylighting member. First, one point in the range of 20 ° or more and 60 ° or less is set as the incident angle of light. Light incident from the set incident angle is emitted from the emission surface through the daylighting member. The emitted light at this time is received while moving the light receiver every 1 ° within the range of the light receiving angle, and the peak intensity of the emitted light at each outgoing angle is measured. And the outgoing angle when the peak intensity of outgoing light becomes the maximum is specified. The peak intensity of the outgoing light at the specified outgoing angle becomes the “maximum peak intensity” of the outgoing light at the set incident angle. Subsequently, the measured intensity of the outgoing light received within the range of ± 3 ° from the specified outgoing angle is converted into the intensity (converted intensity) when the maximum peak intensity is 100%. .
At this time, within the range of the specified output angle ± 3 °, the output angle at which the measurement intensity of the output light is the lowest, that is, “specified output angle + 3 °” and “specified output angle−3 °”, By obtaining the converted intensity of the emitted light with respect to the maximum peak intensity, the lower limit value of the converted intensity with respect to the maximum peak intensity can be specified for all the emitted lights within the range of the specified emission angle ± 3 °. If the lower limit value is within the range of the intensity defined earlier, all the emitted light within the range of the specified emission angle ± 3 ° will show the converted intensity within the range of the intensity defined earlier. .
In addition, let the conversion intensity value of the emitted light with respect to the maximum peak intensity at the specified emission angle ± 3 ° be the light diffusivity for the light incident from the set incident angle.
Next, another point in the range of 20 ° to 60 ° is set as the incident angle, and measurement is performed in the same manner. For example, the incident angle is set every 10 ° within a range of 20 ° to 60 °, and measurement is performed for each set incident angle. In this embodiment, which will be described later, the incident angles were set to 20 °, 30 °, 40 °, 50 °, and 60 °.
In this way, while changing the incident angle within the above range, the emission angle at which the emitted light has the maximum peak intensity is specified for each incident angle, and the maximum of the emitted light received within the specified emission angle ± 3 ° range. By obtaining the converted intensity with respect to the peak intensity, the light diffusibility of the daylighting member of the present invention can be determined. In the daylighting member of the present invention, the converted intensity of the outgoing light within the range of the outgoing angle ± 3 ° indicating the maximum peak intensity with respect to all the incident angles within the range of 20 ° to 60 ° is in the above range. By being inside, desired light diffusibility is exhibited.

In the daylighting member of the present invention, as a method for enabling the above-described light diffusibility to be exhibited, a structure capable of exhibiting a light diffusing function on an incident surface or an output surface (hereinafter, referred to as a light diffusing structure) may be used. ) Is provided. Specifically, the light diffusion structure is a structure in which the incident surface or the emission surface has an uneven shape showing a desired surface roughness, or fine particles that cause light diffusion on the incident surface or the emission surface (hereinafter referred to as light diffusion particles). In some cases). Among them, the daylighting member of the present invention is preferably provided with a light diffusion structure on the light exit surface located on the outermost side of the daylighting member because the above-described optical characteristics are easily exhibited.
The surface roughness of the light reflecting surface and details of the light diffusion structure will be described later.

II. Aspects of Daylighting Member The daylighting member of the present invention includes an incident surface that is a surface on which light is incident, an exit surface that is a surface on which light is emitted and faces the incident surface, and the incident surface. And at least a plurality of light reflecting surfaces that are arranged so as to intersect the incident surface and the emitting surface between the emitting surfaces and reflect the light incident from the incident surface toward the emitting surface, The above-mentioned optical characteristics are shown.

A. Light Reflecting Surface The light reflecting surface in the present invention is disposed between the incident surface and the emitting surface so as to intersect the incident surface and the emitting surface, and directs light incident from the incident surface toward the emitting surface. It is a reflective surface. Since the light reflecting surface reflects incident light with high efficiency, the amount of light emitted from the light emitting surface can be increased, and the light can be emitted in a desired direction. Thereby, the daylighting member of the present invention can exhibit high daylighting performance.
The light reflecting surface is disposed between the incident surface and the emitting surface in a direction intersecting with the incident surface and the emitting surface, so that “the light reflecting surface is between the incident surface and the emitting surface”. It is said to be arranged. Further, the light reflecting surface intersects with the incident surface and the emitting surface, as illustrated in FIG. 4B described later, the light reflecting surface or an extended surface of the light reflecting surface is the emitting surface and the incident surface. Including the case of crossing.

  The light reflecting surface preferably has high smoothness in order to reflect a lot of light. Specifically, the arithmetic average roughness (Ra) of the light reflecting surface is preferably 200 nm or less, more preferably 25 nm or less, and particularly preferably 10 nm or less. This is because if the arithmetic average roughness (Ra) of the light reflecting surface is larger than the above upper limit value, light scattering may occur on the light reflecting surface, which may make it difficult to obtain desired lighting properties.

The arithmetic mean roughness (Ra) of the light reflecting surface is measured by a measurement method using a non-contact white interferometer (for example, Zygo NewView 6200 manufactured by Canon), or by cross-sectional observation using a scanning electron microscope (SEM). Determined by the method.
When a non-contact type white interferometer is used, the three-point average value measured in a measurement range of 50 μm × 50 μm can be used as the arithmetic average roughness (Ra). When a scanning electron microscope (SEM) is used, the cross section of the light reflecting surface is observed by SEM at 23 ° C. according to JIS B0601: 2001, and an interface outline (roughness curve) is obtained from the obtained image. Is extracted from the roughness curve, and only the reference length L is extracted in the direction of the average line. The average curve direction of the extracted portion is the X axis, and the direction of the vertical magnification is the Y axis. ), The value calculated by applying the roughness curve equation to the integral equation defined in JIS B0601: 2001 can be used as the arithmetic average roughness (Ra).

The light reflecting surface may be orthogonal to the incident surface and the emitting surface, and the light reflecting surface 3 may be inclined with respect to the incident surface 1 and the emitting surface 2 as shown in FIG.
In particular, the light reflecting surface is preferably inclined with respect to the incident surface. Specifically, the light reflecting surface is inclined with respect to the incident surface with an incident angle of 40 ° or more. It is preferable that the angle can be emitted at an emission angle smaller than the angle. This is because by jumping up the light so that the emission angle becomes smaller than the incident angle, it is possible to exhibit high daylighting performance in a wide range in the normal direction with respect to the emission surface.
Further, as shown in FIG. 3A, the light reflecting surface 3 may have a plurality of surfaces (3a to 3c) having different inclination angles with respect to the incident surface 1, as shown in FIG. 3B. A part of the light reflecting surface 3 may have a curved surface (3d), and the tangent to the curved surface may be inclined with respect to the incident surface 1. The angle of inclination of the light reflecting surface with respect to the incident surface is an axis in the direction normal to the incident surface, and the angle formed by the axis and the light reflecting surface or an extension line of the light reflecting surface is subtracted from 90 °. It is a portion indicated by θs in FIGS. 2 and 3A. When a part of the light reflecting surface has a curved surface, the inclination angle refers to an angle obtained by subtracting an angle formed by the axis and the tangent line of the light reflecting surface from 90 °.
In particular, the light reflecting surface is preferably a multistage shape having a plurality of surfaces having different inclination angles. This is because the light can be bounced up so that the emission angle becomes smaller than the incident angle with respect to the light incident at various incident angles. In addition, the multi-stage shape allows the incident light to be repeatedly reflected, the light can be bounced up to a desired angle, and the emission angle can be further reduced.
The multi-stage shape is preferably a two-stage shape or a three-stage shape.

  When the light reflecting surface has a multi-stage shape, it is preferable that the surface closer to the incident surface side has a smaller inclination angle with respect to the incident surface. This is because the target range of the incident angle of incident light that can jump up the light in a desired direction on the light reflecting surface can be widened.

The daylighting member of the present invention has a plurality of light reflecting surfaces between the incident surface and the reflecting surface. The shape of each light reflecting surface may be the same or different. In addition, the inclination angles of the light reflecting surfaces with respect to the incident surface may all be the same, or may be different for each light reflecting surface.
In particular, when the daylighting member of the present invention is used so that the entrance surface and the exit surface are upright with respect to the ground, the inclination angle θs of the light reflection surface with respect to the entrance surface gradually increases from the ceiling side to the ground side. It is preferable. The smaller the tilt angle θs of the light reflecting surface with respect to the incident surface, the more the light can travel. On the other hand, the greater the tilt angle θs of the light reflecting surface with respect to the incident surface, the more light travels immediately above the daylighting member. It is because it becomes possible to make it.

As a mode of the light reflecting surface, it is only necessary to reflect light with a desired reflectance. For example, a light deflecting unit having a refractive index higher than that of air is disposed between the incident surface and the emitting surface, or the refractive index is By disposing the light deflecting portion and the light transmitting portion made of different materials in contact with each other, it is possible to obtain a different refractive index interface that causes reflection of light by utilizing a refractive index difference. Among the different refractive index interfaces, the different refractive index interface through which light travels from the high refractive index region to the low refractive index region becomes a total reflection surface, and thus can reflect light with high reflectance.
The light reflecting surface may be a mirror reflecting surface on which a metal film or the like is formed.

B. Incident surface or exit surface The incident surface in the present invention is the surface on the light incident side of the daylighting member. Further, the emission surface in the present invention is a surface on the light emitting side where light is emitted, and is a surface facing the incident surface. The entrance surface and the exit surface of the daylighting member may be virtual surfaces according to the aspect of the daylighting member of the present invention. Further, as described above, the incident surface or the emission surface of the daylighting member may have a light diffusion structure that can exhibit the above-described optical characteristics.

C. Others The daylighting member of the present invention is usually disposed so as to intersect between the entrance surface and the exit surface, and has a facing surface at a position facing the light reflecting surface. In other words, the daylighting member of the present invention is disposed between the entrance surface and the exit surface and has a facing surface at a position facing the light reflecting surface.
If the opposing surface is a different refractive index interface or a specular reflecting surface, the opposing surface can also function as a light reflecting surface.

  As described above, the daylighting member of the present invention may have an arbitrary layer such as a light diffusion layer having a light diffusion structure in order to be able to exhibit desired optical characteristics. The light diffusion layer will be described later.

D. Aspect of Daylighting Member The aspect of the daylighting member of the present invention is not particularly limited as long as it has at least the above-described incident surface, exit surface, and light reflecting surface and has predetermined optical characteristics. Examples of the daylighting member of the present invention include the following modes.
That is, the first aspect of the daylighting member of the present invention is such that the daylighting member includes a light control layer and a light diffusion layer disposed on one surface side of the light control layer, A plurality of light transmission parts arranged in a direction intersecting with the light incident surface and the light emission surface, and a plurality of light deflection parts arranged between the adjacent light transmission parts. It is an aspect in which at least one of the interfaces located in the direction intersecting the light incident surface and the light exit surface between the light deflecting portions is a daylighting film that is the light reflecting surface.
That is, the first aspect of the daylighting member of the present invention is such that the daylighting member includes a light control layer and a light diffusion layer disposed on one surface side of the light control layer. A plurality of light transmission portions disposed between the incident surface and the light exit surface, and a plurality of light deflection portions disposed between the adjacent light transmission portions, the light transmission portion and the light deflection portion. Among these, at least one of the interfaces located between the entrance surface and the exit surface is a daylighting film having the light reflecting surface.

Further, according to a second aspect of the lighting member of the present invention, the lighting member includes a first glass layer, a first sealing portion, a light control layer, a second sealing portion, and a second glass layer. In this order, and the light control layer is the same as the light control layer in the daylighting member of the first aspect, and the light diffusion layer is formed on one surface of the first glass layer or the second glass layer. Is a laminated glass in which is disposed.
Hereinafter, each aspect of the lighting member of the present invention will be described.

1. The first aspect of the daylighting member The first aspect of the daylighting member of the present invention (hereinafter sometimes referred to as “this aspect” in this section) is that the daylighting member is one of the light control layer and the light control layer. A light diffusing layer disposed on the surface side of the light, and the light control layer includes a plurality of light transmissive portions disposed in a direction intersecting the light incident surface and the light emitting surface, and the adjacent light transmissive portions. A plurality of light deflecting portions disposed between the light transmitting portion and the light deflecting portion, wherein at least one of the interfaces located in a direction intersecting the light incident surface and the light emitting surface is the light. It is a daylighting film which is a reflective surface.
In the daylighting film, the light control layer side surface may be the incident surface (light incident surface of the daylighting film) of the daylighting member of the present aspect, and the light diffusion layer side surface of the daylighting member of the present aspect. The incident surface (the light incident surface of the daylighting film) may be used.

The daylighting member of this aspect is demonstrated with reference to figures. FIG. 4A and FIG. 4B are a schematic perspective view and a cross-sectional view showing an example of the daylighting member of this aspect, that is, a daylighting film.
The daylighting member 10 of this embodiment is a daylighting film having the light control layer 20 and a light diffusion layer 22A disposed on the light emission surface side of the light control layer 20 via the base material layer 21. The light diffusion layer 22A will be described later.
The light control layer 20 illustrated in FIG. 4 is formed on the light incident surface 1 side of the light transmitting portion 11 and the light transmitting surface 11 of the refractive index n1 made of a transparent resin. 2, a plurality of grooves 13 formed in the thickness direction of the light transmission portion 11, and a light deflection portion 12 formed in the plurality of groove portions 13 and having a refractive index n2 different from that of the light transmission portion 11. Have. The light transmission part 11 has a single-layer structure in which a plurality of light transmission parts 11 located between adjacent light deflection parts 12 are connected. Such a structure of the light control layer is called a louver type. The light deflection unit 12 is a resin layer made of a transparent resin having a lower refractive index than that of the transparent resin constituting the light transmission unit 11. The side surface f of the groove portion 13 positioned in the thickness direction of the light transmission portion 11 becomes a different refractive index interface because the light transmission portion 11 and the light deflection portion 12 having different refractive indexes are in contact with each other, at least one of which is the light reflection surface 3. Function.
Moreover, although not shown in figure, the lighting member which has a some light transmission part and a light deflection part separately on a base material so that it may illustrate in FIG. 1 is also contained in this aspect.

According to this aspect, by using the daylighting film having the above-described configuration, the interface between the light transmitting portion and the light deflecting portion in the light control layer becomes a light reflecting surface, and light is splashed by the light reflecting surface. Can increase the amount of light collected. Moreover, since light is diffused by the light diffusion layer, high privacy concealment can be exhibited in the entire daylighting film. Furthermore, by setting it as the daylighting film which has the above-mentioned structure, installation to desired positions, such as a window glass, becomes easy and it becomes easy to show | play the effect of this invention.
Hereinafter, the lighting member of this aspect is demonstrated for every structure.

(1) Light diffusion layer The light diffusion layer in this aspect is a layer arrange | positioned at the one surface side of a light control layer.
Here, the light diffusing layer is “arranged on one surface side of the light control layer” means that the light diffusing layer may be directly disposed on one surface of the light control layer. It may be arranged via.

(A) Optical properties The light diffusing layer is not particularly limited as long as it has optical properties that allow the entire daylighting member to exhibit the above-described translucency and light diffusibility when used in combination with the light control layer.
Specifically, the light diffusion layer preferably has a haze value of 30% or more, more preferably 40% or more, and particularly preferably 45% or more. When the haze value of the light diffusion layer indicates the above range, it is possible to diffuse the emitted light that is bounced up and emitted from the light control layer over the entire space, and suppresses the brightness contrast of the space to obtain an anti-glare effect. Because it can. In addition, since the haze value of the light diffusion layer is high, the privacy hiding property can be improved by the light diffusion effect of the light diffusion layer. A haze value is a value measured by the method based on JISK7136 using automatic haze computer HZ-2 (Suga test machine).

  Moreover, the light-diffusion layer should just have a total light transmittance of 80% or more, and it is preferable that it is 85% or more especially. The reason why the total light transmittance of the light diffusion layer is within the above range is the same as the reason described in the above-mentioned section “I. Optical characteristics A. Translucency”.

(B) Aspect of Light Diffusion Layer Aspect of the light diffusion layer capable of exhibiting the above optical characteristics may be any aspect having the above-described light diffusion structure. For example, a resin having light permeability and light diffusion particles are used. The 1st aspect to include and the 2nd aspect which has the uneven | corrugated shape in which the light-diffusion layer surface shows desired surface roughness are mentioned.
Hereinafter, each aspect of the light diffusion layer will be described.

(I) 1st aspect The light-diffusion layer of this aspect is a layer containing resin and light-diffusion particle | grains which have a light transmittance. In the light diffusing layer of this embodiment, the resin is a base material, and the light diffusing particles are dispersed in the resin, and the light hitting the light diffusing particles is diffused by a difference in refractive index between the light diffusing particles and the resin. be able to. Note that light diffusion caused by the difference in refractive index between the light diffusing particles and the resin may be referred to as internal diffusion.

  The daylighting member 10 illustrated in FIG. 4 includes the light diffusion layer 22 </ b> A of the first aspect, and the light diffusion layer 22 </ b> A is obtained by dispersing the light diffusion particles 31 in the resin 32.

The resin contained in the light diffusing layer of this embodiment is not particularly limited as long as it exhibits desired light transmittance and can hold and fix the light diffusing particles, and examples thereof include thermoplastic resins and cured resins. The curable resin includes an ionizing radiation curable resin cured by irradiation with ionizing radiation and a thermosetting resin cured by heating. Examples of the ionizing radiation curable resin include an ultraviolet curable resin, a visible light curable resin, and a near infrared curable resin. The “ionizing radiation” includes, for example, ultraviolet rays and electron beams, electromagnetic waves such as X-rays and γ-rays, and charged particle beams such as α-rays and ion beams. Hereinafter, the same applies to the cured resin and the ionizing radiation.
Specific examples of the resin include, for example, JP-A-2014-115669, JP-A-2012-199176, JP-A-2011-186074, JP-A-2009-230155, JP-A-2005-241920, and the like. It can be the same as that of resin used for the light-diffusion layer disclosed.

The specific light transmittance of the resin may be any size as long as a light diffusion layer formed by dispersing light diffusion particles described later can exhibit the above-described optical characteristics.
The resin may be colorless or colored as long as it has light transmission properties, but is preferably colorless.

The light diffusing particles contained in the light diffusing layer of this embodiment preferably have high light transmittance. The visible light transmittance of the light diffusing particles may be any size as long as the light diffusing layer formed by dispersing the light diffusing particles in the resin can exhibit the above optical characteristics. Specifically, it is preferably 80% or more, more preferably 83% or more, and particularly preferably 85% or more.
The visible light transmittance was measured using a infrared visible ultraviolet spectrophotometer (UV3100PC, manufactured by Shimadzu Corporation) and measured in the wavelength range of 380 nm to 780 nm according to JIS A5759: 2008. It is calculated by the calculation formula defined in The visible light transmittance defined in the present specification is a value measured by the same measuring method.

  The light diffusing particles may be colorless or colored as long as they have light permeability, but are preferably colorless. In the case of colored light diffusing particles, the light hitting the light diffusing particles is back scattered, or light is easily absorbed by the light diffusing particles, thereby reducing the light diffusion effect due to forward scattering and the amount of light emitted from the exit surface. This is because the daylighting member of the present invention may not exhibit a desired function.

  As the light diffusing particles, inorganic particles, resin particles, or a mixture of two or more of them can be selected and used depending on the type of resin. Specific examples of the inorganic particles and the resin particles include, for example, Japanese Patent Application Laid-Open Nos. 2014-115669, 2012-199176, 2011-186074, 2009-230155, and 2005-241920. It can be the same as the light diffusing particles disclosed in Japanese Laid-open Patent Publications.

  Examples of the shape of the light diffusion particle include a spherical shape, a spheroid shape, a polyhedron shape, a truncated polyhedron shape, a scale shape, and a needle shape. The particle size distribution may be either monodispersed or polydispersed, and suitable conditions can be selected as appropriate.

The average particle size of the light diffusing particles may be any size that can exhibit the desired light diffusing effect, and in particular, Mie scattering is likely to occur when light is internally diffused. Rayleigh scattering and geometric scattering It is preferable that it is a size which is hard to produce. When the size of the light diffusing particles is approximately the same as the wavelength of light, the light diffusing particles cause Mie scattering. Here, in the Mie scattering, when the particle size relative to the wavelength of light increases, the forward scattering increases compared to the back scattering. For this reason, by setting the average particle size of the light diffusing particles to a size that Mie scattering dominates, forward scattering of light is likely to occur, so that desired optical characteristics can be obtained. Specifically, the average particle size is preferably in the range of 0.5 μm to 20 μm.
If the average particle size of the light diffusing particles is larger than the above range, light backscattering tends to occur predominantly. On the other hand, if the average particle size is smaller than the above range, internal diffusion due to the light diffusing particles hardly occurs, and the light diffusing layer This is because there are cases where the desired function cannot be exhibited.
The average particle diameter means the primary particle diameter when the individual light diffusion particles are dispersed, and the secondary particle diameter when the individual light diffusion particles are aggregated. The average particle diameter of the light diffusing particles is measured by a laser diffraction particle size distribution measuring device.

  In this embodiment, the light diffusing layer may include light diffusing particles having a single average particle diameter, or may include two or more types of light diffusing particles having different average particle diameters.

  About content of the light-diffusion particle in a light-diffusion layer, what is necessary is just to be able to exhibit a desired function, and it can design suitably according to the haze value of a light-diffusion layer.

  The light diffusing layer of this embodiment may contain arbitrary additives such as an initiator, a filler, a crosslinking agent, a polymerization accelerator, a surfactant, and a viscosity modifier in addition to the light diffusing particles and the resin described above. Good. Further, high refractive index ultrafine particles or low refractive index ultrafine particles for adjusting the refractive index of the resin may be contained. Specific high-refractive index ultrafine particles or low-refractive index ultrafine particles can be the same as the particles disclosed in JP 2011-186074 A.

The refractive index ratio between the light diffusing particles and the resin contained in the light diffusing layer of the present embodiment may be a size that allows the light diffusing layer of the present embodiment to exhibit a desired optical characteristic. And if the refractive index of resin differs, it will not specifically limit. Specifically, the ratio of the material having a large refractive index to the material having a small refractive index among the refractive indexes of the light diffusing particles and the resin is preferably more than 1.000 and less than 1.020, and more than 1.000. More preferably, it is less than .010, and more preferably more than 1.000 and less than 1.005.
The refractive index of the light diffusing particles is determined by measuring the turbidity by dispersing equal amounts of the light diffusing particles in the solvent in which the refractive index is changed by changing the mixing ratio of two kinds of solvents having different refractive indexes. It is measured by measuring the refractive index of the solvent when the degree becomes minimum with an Abbe refractometer.
The refractive index of each of the light diffusing particles and the resin is not particularly limited as long as the above refractive index ratio is satisfied. The refractive index of the light diffusing particles may be larger or smaller than the refractive index of the resin. .

  The light diffusion layer of this aspect may have a smooth surface, and as illustrated in FIG. 5, a part of the light diffusion particle 31 has an uneven surface that protrudes from the surface of the light diffusion layer 22B. May be. By making the surface of the light diffusion layer an uneven surface, in addition to internal diffusion, the uneven shape on the surface of the light diffusion layer and the light diffusion layer can be formed in the same manner as in “(ii) Second mode” described later. Light can be diffused by the difference in refractive index between adjacent layers, that is, external diffusion can be caused. For this reason, the haze value of the entire light diffusion layer is the sum of the internal haze generated by internal diffusion and the external haze generated by external diffusion, so that even a thin film can exhibit desired optical characteristics. Become.

Here, the surface of the light diffusing layer is a concavo-convex shape surface, indicating that the surface of the light diffusing layer has a surface roughness that tends to cause Mie scattering when light is externally diffused and hardly causes Rayleigh scattering and geometric scattering. Specifically, the 10-point average roughness Rz of the irregular surface of the light diffusion layer is preferably larger than 0.5 μm. If the 10-point average roughness Rz of the concavo-convex shape surface of the light diffusion layer is larger than the above range, backscattering of light tends to occur predominantly, whereas if smaller than the above range, the function of external diffusion is inferior, This is because the light diffusion layer may not exhibit a desired haze value. The upper limit of the 10-point average roughness Rz of the uneven surface of the light diffusion layer is preferably 6 μm or less.
The 10-point average roughness Rz of the uneven surface of the light diffusing layer is a value measured based on JIS B0601: 1994, and with respect to the average line of the portion where the reference length is extracted from the cross-sectional curve of the object to be measured, It is the value of the difference between the average value of the elevation from the highest to the fifth peak and the average value of the elevation from the lowest to the fifth. Hereinafter, the 10-point average roughness Rz is a value measured by the same method as described above.

  At this time, the refractive index ratio between the light diffusing layer and the other layer in contact with the concavo-convex shape surface of the light diffusing layer may be any size that can cause external scattering, which will be described later. Since it can be the same as that of "ii) 2nd aspect", description here is abbreviate | omitted. The other layer in contact with the uneven surface of the light diffusion layer is usually an air layer. Further, the refractive index of the light diffusion layer at this time refers to the refractive index of the resin.

  The thickness of the light diffusion layer may be any thickness as long as it can exhibit desired optical characteristics, and can be designed as appropriate. For example, in the case of a light diffusing layer having an uneven surface, the thickness of the light diffusing layer is such that the average particle diameter of the light diffusing particles is 0.3 or more and 3 or less when the thickness of the light diffusing layer is 1. It is preferable to design so that The thickness of the light diffusion layer is a stylus type that calculates the thickness by detecting the unevenness by tracing the surface with a stylus using a stylus type film thickness meter (P-15 manufactured by KLA-Tencor Japan Co., Ltd.). It is possible to measure by this method. In addition, as a thickness prescribed | regulated in this specification, the average value of the measurement result of the thickness in the several place of the member used as object may be used.

The method for forming the light diffusing layer of this embodiment is not particularly limited as long as it can form a light diffusing layer capable of exhibiting desired optical characteristics. For example, a method of applying or coating a light diffusion layer composition containing the above-described resin and light diffusion particles on the surface of a light control layer or the like and curing the light diffusion layer composition, extrusion molding, injection Examples thereof include a method of forming a sheet by molding or the like.
The composition for light diffusion layer may contain a solvent as necessary. For example, by using a permeable solvent that is permeable to the material of the layer in which the light diffusion layer such as the light control layer is provided as the solvent, the light diffusing particles are embedded in the surface of the light control layer or the like. A light diffusion layer having a shaped surface can be formed.
The method for curing the coating film of the light diffusion layer composition can be appropriately selected depending on the type of resin in the coating film, and for example, a method of irradiating ionizing radiation such as ultraviolet rays or electron beams is used. When the coating film is cured, when the coating film contains a solvent, it is preferable to remove the solvent by drying or the like and then cure the coating film.

(Ii) Second Aspect The second aspect of the light diffusing layer (hereinafter sometimes referred to as this aspect in this section) has an uneven shape in which the surface of the light diffusing layer exhibits a desired surface roughness.

  The daylighting member 10 illustrated in FIG. 6 has the light diffusing layer 22C of the second aspect, and has a concavo-convex shape indicating a desired surface roughness on the surface.

  According to this aspect, when the light is incident on the concavo-convex shape surface of the light diffusion layer, the above-described optical characteristics can be exhibited by external diffusion.

  The material of the light diffusing layer of this embodiment may be any material that exhibits a desired light transmittance and can form a concavo-convex shape on the surface, and includes, for example, a cured resin. Specifically, a cured resin obtained by curing an ionizing radiation curable resin disclosed in JP 2000-352607 A can be mentioned. It is also possible to use the resin described in “(i) First aspect”.

  In addition to the above resin, it contains the light diffusing particles described in the section “(i) First aspect”, ultrafine particles of high refractive index and ultrafine particles of low refractive index for adjusting the refractive index, and optional additives. You may go out.

The thickness of the light diffusing layer of this embodiment may be any size as long as it has an uneven shape capable of causing external diffusion on the surface and exhibiting desired optical characteristics, for example, 3 μm to 1000 μm. In particular, the range of 10 μm to 30 μm is preferable.
In addition, the measuring method of the thickness of the light diffusion layer of this aspect uses the same method as the measuring method of the thickness of the light diffusion layer of the first aspect.

  In the light diffusing layer of this aspect, the surface roughness for causing external diffusion on the uneven surface of the light diffusing layer is likely to cause Mie scattering when light is diffused externally, causing Rayleigh scattering and geometric scattering. It is preferable that the size is difficult. Specifically, the 10-point average roughness Rz of the light diffusion layer is preferably in the range of 1 μm to 1000 μm. If the 10-point average roughness Rz of the light diffusing layer is larger than the above range, light backscattering tends to occur predominantly. On the other hand, if it is smaller than the above range, external diffusion hardly occurs on the surface of the light diffusing layer. This is because the desired function may not be exhibited.

As a method for forming the light diffusing layer of this embodiment, a method for forming the light diffusing layer containing the above-mentioned resin on the surface of the light control layer or the like and curing the coating film, or curing the coating film. And a method of adjusting the surface roughness by applying a surface treatment, and a method of adjusting the surface roughness by forming a sheet by extrusion molding, injection molding or the like and then applying the surface treatment.
As the surface treatment method, a conventionally known method such as plasma treatment, corona discharge treatment, or UV ozone treatment can be used.

(C) Arrangement Position of Light Diffusion Layer The arrangement position of the light diffusion layer may be arranged on one surface side of the light control layer. Here, the light diffusing layer is disposed on one surface side of the light control layer may be directly disposed on one surface of the light control layer, and one surface of the light control layer as described later. When the base material layer is arrange | positioned on the top, you may arrange | position on the said base material layer.
Further, the one surface side of the light control layer may be the light incident surface side of the light control layer, or may be the light exit surface side. The light incident surface of the light control layer is a surface located on the incident surface side of the daylighting member in the surface of the light control layer. Moreover, the light emission surface of the light control layer is a surface located on the light emission surface side of the daylighting member in the surface of the light control layer. Especially, it is preferable that the said light-diffusion layer is located in the light emission surface side rather than the light control layer. That is, it is preferable that the light diffusing layer is located closer to the emission surface of the daylighting member than the light control layer. When a light diffusing layer is provided on the incident surface side, incident light is scattered near the incident surface, so scattered light that is not emitted from the exit surface side, light that does not reach the light reflecting surface, and the critical angle of the light reflecting surface is set. When the light reaches at an incident angle that exceeds, the amount of light reflected from the light reflecting surface and emitted from the exit surface side decreases, and when the amount of collected light decreases, the intensity of the emitted light decreases, and the desired lighting effect This is because there is a case that cannot be obtained.

When the light diffusion layer is directly disposed on one surface of the light control layer, the light diffusion layer may be integrated with the light control layer.
The fact that the light diffusion layer is integral with the light control layer means that there is no interface between the light diffusion layer and the light control layer, that is, the surface facing the surface of the light control layer having the groove (hereinafter referred to as the non-groove portion side surface). In the “(b) Aspect of light diffusing layer (i) Aspect in which light scattering particles described in the first aspect” exist, and the non-groove portion side surface of the light control layer is “(b) Light Aspect of diffusion layer (ii) It means an aspect having the concavo-convex shape described in the section “second aspect”. The presence of light scattering particles on the non-groove portion side surface of the light control layer means that part or all of the light scattering particles are buried in the non-groove portion side surface.

Moreover, when the base material layer is arrange | positioned on the output surface of a light control layer, it is preferable that a light-diffusion layer is integral with the said base material layer. This is because a single layer of the base material layer can exhibit the function of supporting the light control layer and the function of imparting desired optical properties to the entire daylighting film.
That the light diffusion layer is integral with the base material layer means that there is no interface between the base material layer and the light diffusion layer, that is, the base material layer is “(b) Aspect of light diffusion layer (i) First aspect” The aspect containing the light-scattering particles described in the section, the surface facing the light control layer side surface of the base material layer is the concavo-convex shape described in the section “(b) Aspect of light diffusion layer (ii) Second aspect” It is said that it is an aspect which has. That the base material layer contains light scattering particles means that the light scattering particles are dispersed in the base material layer or that part of the light scattering particles protrudes from the surface of the base material layer. The base material layer will be described later.
FIG. 7 shows an example of an aspect in which the light diffusion layer and the base material layer are integrated (an aspect having the base material layer 24 with a light diffusion function) in the daylighting member (lighting film) of this aspect.

(2) Light Control Layer As the light control layer in this embodiment, a plurality of light deflecting units 4 having light reflecting surfaces 3 are arranged in parallel on the base material layer as shown in FIG. The structure which has two or more permeation | transmission parts (air layer 5) and the louver type structure are mentioned. The louver type structure includes a light transmitting portion made of a transparent resin, a plurality of groove portions formed on one surface of the light transmitting portion in a direction intersecting the light incident surface and the light emitting surface, and a plurality of groove portions. And a light deflecting portion that is formed in the groove portion and has a refractive index different from that of the light transmitting portion.
In the louver structure, the light transmission part has a single layer structure in which a plurality of light transmission parts located between adjacent light deflection parts are connected. Further, in the louver type structure, “a plurality of grooves formed on one surface of the light transmitting portion in a direction intersecting with the light incident surface and the light emitting surface” means “one of the light transmitting portions. In other words, “a plurality of grooves having the light reflecting surface formed on the surface”.
Especially, since the light control layer itself can be formed into a sheet shape, the light control layer is preferably a louver type.
Hereinafter, the louver type light control layer will be described.

(A) Groove part The groove part in this aspect is formed on one surface of the light transmission part in a direction intersecting the light incident surface and the light exit surface. That is, the groove portion is formed on one surface of the light transmission portion and has the light reflection surface.
The direction intersecting with the light incident surface and the light exit surface of the light transmitting portion is the direction intersecting with the light incident surface and the light exit surface of the daylighting member.
Usually, the groove is formed on the light incident surface side surface of the light transmitting portion.

  Examples of the opening shape of the groove include a linear shape and a curved shape. Moreover, the adjacent groove portions may be formed in parallel, may be formed randomly, or may be formed intersecting each other. Among these, it is preferable that the plurality of grooves are linear and formed in parallel. The length of such a groove is not particularly limited, and can be appropriately set according to the use of the daylighting member. The length of the groove means the length in the longitudinal direction of the groove opening when viewed from the surface on the side where the groove is formed on the surface of the light transmitting portion. The surface of the light transmitting portion on which the groove is formed may be referred to as “a surface including the groove opening of the light transmitting portion”.

The shape of the groove portion viewed from the thickness direction of the light transmission portion, that is, the cross-sectional shape of the groove portion is not particularly limited, and can be appropriately designed to have a shape in which the daylighting function by the light deflection portion is easily exhibited. Specific examples include a triangle, a rectangle, a wedge shape, and a polygon. In addition, at least one of the side surfaces of the groove portion may have a multistage shape, or a part thereof may be curved. Furthermore, the corners of the grooves may have a curvature.
The “side surface of the groove portion” refers to an interface extending in the direction intersecting the light incident surface and the light exit surface (thickness direction of the light transmissive portion) among the interfaces between the light transmissive portion and the light deflection portion, This is a portion indicated by f in FIGS. 4B and 5 to 8.

The width of the groove is not particularly limited as long as the desired daylighting function can be exerted, but the length of the widest portion is in the range of 5 μm to 150 μm, in particular in the range of 10 μm to 100 μm, in particular 12 μm to It is preferably within the range of 50 μm. If the width of the widest portion of the groove is larger than the above range, light may not be easily transmitted through the light transmitting portion and the light deflecting portion. On the other hand, if the width is smaller than the above range, a desired function may be achieved in the light deflecting portion. This is because there is a case where it cannot be fulfilled.
In addition, the width of the groove means the width of the light deflection unit, and is a portion indicated by a in FIG. 4B, for example.

The depth of the groove is not limited as long as the daylighting function of the light deflector is easily exhibited. For example, the depth of the groove is in the range of 10 μm to 250 μm, particularly in the range of 30 μm to 200 μm, and particularly in the range of 50 μm to 200 μm. Is preferred. At this time, the depth of the groove is preferably 50% or more with respect to the thickness of the light transmission part, and more preferably in the range of 70% to 98%.
The depth of the groove portion means the length from the surface including the groove opening of the light transmitting portion to the tip of the groove portion, that is, the thickness of the light deflection portion, and is a portion indicated by b in FIG. 4B, for example.

  The plurality of groove portions may be formed at equal intervals, or may be formed at different intervals. The pitch width of the groove portions, that is, the arrangement interval of the light deflecting portions is not limited as long as the daylighting function by the light deflecting portion is easily exhibited, and is the widest width between adjacent groove portions in the plane including the groove opening of the light transmitting portion. Is preferably in the range of 10 μm to 200 μm, more preferably in the range of 12 μm to 150 μm, and particularly preferably in the range of 13 μm to 100 μm. In addition, the distance between groove parts is a part shown by c in FIG.4 (b), for example.

  As will be described later, the two side surfaces in the groove portion are different refractive index interfaces because the light transmitting portion and the light deflecting portion exhibit different refractive indexes. One of the two opposite refractive index interfaces facing each other is a light reflecting surface because light travels from the high refractive index region to the low refractive index region and total reflection occurs.

(B) Light transmissive portion As a transparent resin constituting the light transmissive portion, a resin having a high light transmittance capable of forming a light transmissive portion exhibiting a light transmittance described later and having a refractive index different from that of the light deflecting portion. If it is, it will not specifically limit, However, From a viewpoint of the shape stability of a groove part, it is preferable to comprise with curable resin. Examples of the curable resin include a thermosetting resin and an ionizing radiation curable resin. Among them, an ionizing radiation curable resin is preferable from the viewpoint of versatility, curability, and light transmittance, and an ultraviolet curable resin is particularly preferable.
Specific examples of the transparent resin include a resin used as a light transmissive material disclosed in Japanese Patent Application Laid-Open No. 2014-215580, and a thermosetting material used in a light transmission part disclosed in Japanese Patent Application Laid-Open No. 2014-137441. Examples thereof include cured products of resins and ionizing radiation curable resins.

  Depending on the type of resin used, the light transmission part is, for example, a weather resistance improver such as an ultraviolet absorber or a light stabilizer disclosed in JP 2014-137441 A, a photopolymerization initiator, an antioxidant, It may contain additives such as cross-linking agents, hard coat agents, scratch-resistant fillers, polymerization inhibitors, antistatic agents, leveling agents, thixotropic agents, coupling agents, plasticizers, antifoaming agents and fillers. .

The refractive index of the light transmitting portion may be any size as long as it exhibits a refractive index different from that of the light deflection portion and can exhibit a desired refractive index difference with the light deflection portion described later. One of the side surfaces of the groove portion extending in the thickness direction of the light transmitting portion can be used as a light reflecting surface by utilizing the magnitude relationship between the refractive indexes of the light transmitting portion and the light deflecting portion. This is because the amount of collected light can be increased by jumping up the incident light on the light reflecting surface.
Especially, it is preferable that the refractive index of a light transmissive part is higher refractive index than the said light deflection | deviation part. In the daylighting member of this aspect, since the ratio of light incident from the light transmitting portion is large, the light is allowed to travel from the light transmitting portion having a high refractive index to the light deflecting portion having a low refractive index, so that the light reflecting surface Total reflection of light will occur. This is because the amount of light jumped up on the light reflecting surface can be increased.
The specific refractive index of the light transmission part is preferably in the range of 1.50 to 1.80, and particularly preferably in the range of 1.55 to 1.65. The refractive index of the light transmission part is a value at a wavelength of 589 nm measured using a multiwavelength Abbe refractometer (manufactured by Atago Co., Ltd.).

The thickness of the light transmission part is not particularly limited as long as the light control layer can have a desired optical characteristic, and can be appropriately designed according to the depth of the groove part. For example, the thickness is preferably in the range of 50 μm to 300 μm, more preferably in the range of 60 μm to 250 μm, and particularly preferably in the range of 70 μm to 220 μm. If the thickness of the light transmitting portion is larger than the above range, the amount of light collected may decrease due to a decrease in light transmittance. On the other hand, if the thickness is smaller than the above range, the depth of the groove portion becomes relatively shallow, and light is reduced. There may be a case where a desired amount of light cannot be obtained due to a decrease in the amount of light splashed on the reflecting surface.
The thickness of the light transmissive portion refers to the length from the surface of the light transmissive portion on the side where the groove is formed to the opposite surface, that is, the thickness of the light control layer.

  The light transmitting portion preferably has high light transmittance. For example, the visible light transmittance is preferably 80% or more, more preferably 83% or more, and particularly preferably 85% or more.

(C) Light deflection unit The light deflection unit in this aspect is formed in the plurality of grooves.
The light deflection unit may be a resin layer as illustrated in FIGS. 4 to 7, or may be an air layer in the groove as illustrated in FIG. 8.
Hereinafter, the light deflection unit will be described separately for a resin layer and an air layer.

(I) Resin layer When the light deflection part is a resin layer, the resin constituting the resin layer may be a resin having light permeability and a refractive index different from that of the light transmission part. For example, ionizing radiation curing Resins can be mentioned. Of these, ultraviolet curable resins and electron beam curable resins are preferred. The specific resin can be the same as “(b) Light transmitting portion”.
The resin layer may contain any additive described in the section “(b) Light transmission part”.

  The refractive index of the light deflection unit when the light deflection unit is a resin layer may be any refractive index different from the refractive index of the light transmission unit, and is preferably lower than the refractive index of the light transmission unit. The reason for this is the same as that described in the section “(b) Light transmissive part”, and the description thereof is omitted here. The refractive index of the light deflector is preferably in the range of 1.40 to 1.80, and more preferably in the range of 1.40 to 1.55. The refractive index is measured by the same method as the refractive index of the light transmission part.

  When the light deflection part is a resin layer, the resin layer preferably has a high light transmittance, and specifically, the visible light transmittance of the light deflection part is preferably 80% or more. % Or more, and particularly preferably 85% or more.

(Ii) Air layer When the light deflecting part is an air layer, the refractive index of air is usually about 1.0, which is lower than the refractive index of the light transmitting part fat described above, which corresponds to the two side surfaces of the groove part. The two interfaces of the light transmitting portion and the light deflecting portion to be used can be a different refractive index interface, and one of the different refractive index interfaces can be a light reflecting surface. In addition, by using an air layer, the light deflection unit can have high light transmittance.

(Iii) Others About the width | variety, thickness, shape, and arrangement | positioning distance of the said optical deflection | deviation part, it can be made to be the same as that of the width | variety of the groove part mentioned above, depth, a shape, and the distance between groove parts.

(D) Others As the refractive index difference between the light transmission part and the light deflection part, the larger the difference, the better. This is because the larger the refractive index difference, the more efficiently the light can be reflected at the different refractive index interface including the light reflecting surface even when the incident angle of light with respect to the daylighting member is large.
The specific refractive index difference between the light transmitting part and the light deflecting part is preferably 0.03 or more, particularly preferably 0.05 or more. If the difference in refractive index is less than the above range, it becomes impossible to efficiently reflect light at the different refractive index interface including the light reflecting surface when the angle of incident light increases. In addition, when chromatic dispersion of total reflection occurs, the long wavelength component may not be totally reflected, and only the short wavelength component may be totally reflected, which may cause a change in the color of lighting.

  In the light control layer, the surface on the side where the groove is formed may be the light incident surface of the light control layer, and the surface facing the surface on which the groove is formed may be the light incident surface of the light control layer. . Among these, it is preferable that the surface on which the groove is formed is the light incident surface of the light control layer. This is because it can be controlled by making more light incident on the light reflecting surface.

  As a method for forming the light control layer, a conventionally known method can be used depending on the embodiment. As a method for forming a louver-type light control layer, for example, a light transmissive portion having a plurality of grooves on the surface is formed on a base material layer described later by a method disclosed in Japanese Patent Application Laid-Open No. 2014-085408, and light is emitted. If the deflection part is a resin layer, the groove part is formed by filling a composition containing an ionizing radiation curable resin, which is a resin material of the resin layer, and curing it. If the light diffusion layer and the base material layer are integrated, the light transmission part and the light deflection part may be formed on the light diffusion layer by the method described above.

(E) Other structures of light control layer In the light control layer in this aspect, a plurality of light deflection units having a light reflection surface as shown in FIG. In the case of a structure having a plurality of light transmission parts, the material and arrangement of the light deflection part and the light transmission part can be the same as the material and arrangement of the light deflection part and the light transmission part in the louver structure described above.

(3) Base material layer As for the lighting member of this aspect, the base material layer may be arrange | positioned on one surface of the light control layer. This is because the light control layer is supported and the mechanical strength of the daylighting film can be improved. In particular, the base material layer is preferably disposed on the surface facing the surface on which the groove portion of the light control layer is formed.

As a base material layer, if it has the light transmittance which does not impair the translucency of the lighting member of this aspect, it will not specifically limit, A resin film and a sheet | seat can be used. For example, a polyethylene terephthalate film etc. are mentioned.
The light transmittance and thickness of the base material layer are not particularly limited.
The base material layer may contain light diffusing particles used for the light diffusing layer.

(4) Other members The daylighting member of this embodiment may have an adhesive layer, a hard coat layer, a planarization layer, and the like. These layers are preferably not provided on the light scattering layer. This is because depending on the mode of the light scattering layer, the optical characteristics of the daylighting member of this mode may be impaired.

2. The second aspect of the daylighting member The second aspect of the daylighting member of the present invention (hereinafter sometimes referred to as “this aspect” in this section) is that the daylighting member includes the first glass layer and the first sealing portion. And the light control layer, the second sealing portion, and the second glass layer in this order, the light control layer is the same as the light control layer in the daylighting member of the first aspect, In one embodiment, the light diffusion layer is laminated glass on one surface of the first glass layer or the second glass layer.
In the laminated glass, the surface on the first glass layer side may be the incident surface (light incident surface of the laminated glass) of the daylighting member of this aspect, and the surface on the second glass layer side is the daylighting of this aspect. It may be the incident surface (light incident surface of the laminated glass) of the member.

The daylighting member of this aspect is demonstrated with reference to figures. FIG. 9 is a schematic perspective view and a cross-sectional view showing an example of the daylighting member of this aspect, that is, a laminated glass.
In the daylighting member 10 of this aspect, the first glass layer 41, the first sealing material 42, the light control layer 20, the second sealing material 43, and the second glass layer 44 are laminated in this order. The glass layer 41 side is the incident surface side of the daylighting member 10. A light diffusion layer 22 </ b> A is disposed on the surface of the second glass layer 44.
The light control layer 20 and the light diffusion layer 22A are the same as those illustrated in FIG. 4, and thus description thereof is omitted here.

  According to this aspect, by using the laminated glass having the above-described configuration, the interface between the light transmitting portion and the light deflecting portion in the light control layer becomes a light reflecting surface, and light is splashed by the light reflecting surface. This is because the amount of light collected can be increased. Moreover, since light is diffused by the light diffusion layer, high privacy concealment can be exhibited in the entire laminated glass. Furthermore, by setting it as the laminated glass which has the above-mentioned structure, it becomes easy to install in desired places, such as an opening part, and it becomes easy to show | play the effect of this invention.

  Hereinafter, the lighting member of this aspect is demonstrated for every structure.

(1) Light Diffusing Layer The light diffusing layer in this embodiment is a layer disposed on one surface of the first glass layer or the second glass layer (hereinafter sometimes abbreviated as “glass layer”). It is.
About the aspect and optical characteristic of the light-diffusion layer in this aspect, since it is the same as that of the content demonstrated in the term of "1. 1st aspect of a lighting member", description here is abbreviate | omitted.
Moreover, it is preferable that the said light-diffusion layer is located in the light-projection surface side rather than the said light control layer. The reason for this is also the same as that described in the section “1. First aspect of the daylighting member”, and the description thereof is omitted here.

(2) Light Control Layer Since the light control layer in this aspect can be the same as the light control layer described in the section “1. First aspect of the daylighting member”, description thereof is omitted here. Among them, the light control layer includes a light transmission portion made of a transparent resin, a plurality of grooves formed on one surface of the light transmission portion in a direction intersecting with the light incident surface and the light emission surface, and a plurality of groove portions. It is preferable to have a light deflection part formed in the groove part and having a refractive index different from that of the light transmission part. About the reason and a suitable arrangement | positioning aspect, it is the same as that of the content demonstrated in the term of "1. The 1st aspect of a lighting member."
In the light control layer, “a plurality of grooves formed on one surface of the light transmitting portion in a direction intersecting with the light incident surface and the light emitting surface” means “one surface of the light transmitting portion. In other words, a plurality of grooves having the light reflecting surface formed above.

(3) 1st glass layer and 2nd glass layer The 1st glass layer and 2nd glass layer in this aspect are members which pinch | interpose a light control layer. The first glass layer and the second glass layer are transparent and have high light transmittance. Glass materials used for the first glass layer and the second glass layer include inorganic glass such as soda lime glass, aluminosilicate glass, borosilicate glass, organic glass such as polycarbonate and polymethyl methacrylate, inorganic / organic hybrid glass, etc. Is mentioned.

  Moreover, as a kind of glass used for a 1st glass layer and a 2nd glass layer, the kind generally used for laminated glass, such as a normal glass, a clear float glass, a highly transmissive glass, a heat-resistant glass, a wire mesh glass, is mentioned. Moreover, the kind of glass used for the glass layer integrated with the light-diffusion layer mentioned later is also mentioned.

  The first glass layer and the second glass layer may be made of the same material or different from each other. Moreover, you may have several glass plates as needed.

  The thickness of the first glass layer and the second glass layer may be the same or different. The thickness is preferably in the range of 100 μm to 50 mm, and more preferably in the range of 500 μm to 30 mm. By setting the thickness of the first glass layer and the second glass layer within the above range, a laminated glass having desired mechanical properties and optical properties can be obtained.

  The visible light transmittance of the first glass layer and the second glass layer may be of a level that does not impair the optical properties of the entire laminated glass, for example, 80% or more, preferably 82% or more, and more preferably 83% or more. Especially preferably, it is 85% or more.

One of the first glass layer and the second glass layer is preferably integral with the light diffusion layer. This is because the function of supporting the light control layer and the function of imparting desired optical properties to the entire laminated glass can be exhibited by a single layer of the first glass layer or the second glass layer.
That the light diffusion layer is integral with one of the first glass layer and the second glass layer means that there is no interface between the glass layer and the light diffusion layer, that is, the glass layer itself has a light diffusion function. Specifically, the first glass layer or the second glass layer includes the light scattering particles described in the section “1. First aspect of the daylighting member”, the first glass layer, or the second glass layer. It means that one surface of the glass layer has the desired concavo-convex shape described in the section “1. First aspect of daylighting member”.
Examples of the glass used as the glass layer integrated with such a light diffusion layer include ground glass, frosted glass, and template glass.

  In the lighting member of this aspect, it is preferable that the glass layer located in the output surface side of a laminated glass among the 1st glass layer or the said 2nd glass layer is integral with a light-diffusion layer. The reason for this is the same as the reason described in the section “1. First aspect of the daylighting member”, and the description thereof is omitted here. FIG. 10 shows an example of a mode in which the second glass layer and the light diffusion layer are integrated (a mode having the glass layer 45 with a light diffusion function).

(4) 1st sealing part and 2nd sealing part The 1st sealing part in this aspect and the 2nd sealing part (henceforth abbreviated as "sealing part") are the 1st glass layer. And a light control layer and a member that seals between the second glass layer and the light control layer.
In this aspect, the first sealing portion and the second sealing portion have light transparency.

  The sealing portion may be any member that exhibits high light transmittance and can adhere between the first glass layer and the light control layer and between the second glass layer and the light control layer. It can be an adhesive layer used in glass. As the material for the adhesive layer, for example, thermoplastic resins such as ethylene-vinyl acetate copolymer resin (EVA) and polyvinyl butyral resin (PVB), thermosetting resins, and the like can be used. You may use, and may use it in combination of 2 or more types. Of these, EVA and PVB are used alone or EVA and PVB are used in combination.

  Furthermore, one of the first sealing portion and the second sealing portion may contain a desired amount of light diffusing particles used in the light diffusing layer. This is because the first sealing portion or the second sealing portion can also function as a light diffusion layer, and there is no need to provide a separate light diffusion layer. About content of a light-diffusion particle, it can be made to be the same as that of the quantity demonstrated by the term of "(b) Aspect of a light-diffusion layer (i) 1st aspect."

  As the thickness of the sealing portion, it is possible to seal between the first glass layer and the light control layer and between the second glass layer and the light control layer, and the light transmittance of the lighting member of this aspect For example, it is preferably in the range of 100 μm to 5000 μm, more preferably in the range of 200 μm to 1600 μm.

  The visible light transmittance of the sealing portion can be the same as the visible light transmittance of the glass layer described above.

(5) Others The daylighting member of this aspect may have an arbitrary layer generally used for laminated glass.
Moreover, the lighting member of this aspect can also be used independently as a laminated glass, and can also be used as at least one of the pair of glasses in the multilayer glass in which a hollow layer is provided between the pair of glasses.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Example 1]
As a daylighting member, a daylighting film having a louver type light control layer was formed by the following procedure.

1. Adjustment of composition for light transmission part (adjustment of photocurable prepolymer (P1))
First, bisphenol A ethylene oxide, xylylene diisocyanate, phenoxyethyl acrylate, 2-hydroxyethyl acrylate, and bismuth tri (2-ethylhexanoate) are mixed at a mass ratio of 30: 15: 50: 5: 0.02. And reacted at 80 ° C. for 10 hours to obtain a photocurable prepolymer (P1).

(Preparation of photocurable prepolymer (P2))
Bisphenol A ethylene oxide, isophorone diisocyanate, phenoxyethyl acrylate, and bismuth tri (2-ethylhexanoate) are mixed at a mass ratio of 30: 20: 50: 0.02, reacted at 80 ° C. for 10 hours, and photocured. A prepolymer (P2) was obtained.

(Adjustment of composition for light transmission part)
Next, 30 parts by weight of the photocurable prepolymer (P1), 30 parts by weight of the photocurable prepolymer (P2), 10 parts by weight of phenoxyethyl acrylate as the reactive dilution monomer (M1), and the reactive dilution monomer ( 30 parts by weight of bisphenol A ethylene oxide as M2), 0.03 parts by weight of phosphate ester of tetradecanol ethylene oxide 10 mol adduct as mold release agent (S1), stearylamine as mold release agent (S2) Ethylene oxide 15 mol adduct 0.03 parts by weight, 1 part of 1-hydroxycyclohexyl phenyl ketone (trade name: Irgacure 184, manufacturer name: BASF) as a photopolymerization initiator (I1) is mixed, homogenized, and light A composition for a transmission part was obtained.
The composition for light transmission part was applied at a thickness of 100 μm, and the coating film was cured by irradiating UV light of 800 mJ / cm ² with high-pressure mercury, and using a multiwavelength Abbe refractometer (manufactured by Atago Co., Ltd.). The refractive index measured at a wavelength of 589 nm was 1.550.

2. Preparation of Light Diffusion Layer A 120 μm thick mat film (trade name: PET100FSM-50-H25, manufactured by Toyo Packaging Co., Ltd.) having an uneven shape on one surface was used as the light diffusion layer. In this mat film, the light diffusion layer and the base material layer were integrated, and the haze value was 30%.

3. Production of mold roll A mold roll used for production of the light transmission part was produced. The mold roll was cylindrical and was plated with copper, and the copper plated part was cut with a cutting tool to form a plurality of grooves corresponding to the light transmitting part. A diamond tool was used as the tool. The outer periphery of the copper plating layer of the mold roll was cut at a predetermined pitch in the roll axis direction, and the cut roll was chrome plated.

4). Formation of Light Control Layer The light diffusion layer was conveyed between the mold roll and the nip roll prepared above. In accordance with the conveyance of the light diffusion layer, the composition for the light transmission part is supplied onto the surface opposite to the concavo-convex shape surface of the light diffusion layer, and the pressing force between the mold roll and the nip roll is used. The composition for a light transmission part was filled between the mold rolls. Thereafter, the composition for light transmission part was cured by irradiating with 800 mJ / cm ² of ultraviolet light from the substrate layer side with a high-pressure mercury lamp to form a light transmission part. Thereafter, the light transmission part is released from the mold roll by a peeling roll, and the light control layer in which the light polarization parts in the plurality of grooves formed on one surface side of the light transmission part are air layers is used as the light control layer. It formed on the surface on the opposite side to the uneven | corrugated shaped surface of a diffusion layer.
The obtained light control layer has a cross-sectional shape shown in FIG. 4B, the width of the light deflection portion (groove portion) (a in FIG. 4B) is 32.1 μm, and the light deflection portion (groove portion) The depth (b in FIG. 4B) was 165 μm, and the distance between the arrangements of the light deflection portions (grooves) (c in FIG. 4B) was 26.9 μm.

5. Formation of adhesive layer 100 parts by weight of an acrylic resin adhesive (trade name: SK Dyne 2094, Soken Chemical Co., Ltd., solid content 25.0%, mixed solvent of ethyl acetate and methyl ethyl ketone) and a crosslinking agent (E-5XM) , L-45, Soken Chemical Co., Ltd., solid content 5.0%) 0.28% by mass, 1,2,3-benzotriazole 0.25 parts by weight and diluent (toluene / methyl ethyl ketone / cyclohexanone = 27 .69 g / 27.69 g / 4.61 g) and 32.0 parts by weight were mixed to obtain an adhesive layer composition.
The adhesive layer composition is applied onto a release film (trade name: E7007, manufactured by Toyobo Co., Ltd., thickness 38 μm), dried, and bonded to the surface having the groove opening of the light control layer. Obtained.

[Example 2]
A daylighting film was obtained in the same manner as in Example 1 except that a matte film having a haze value of 50% was used as the light diffusion layer (integrated type of light diffusion layer and substrate layer, thickness 120 μm).

[Example 3]
A daylighting film was obtained in the same manner as in Example 1 except that a matte film having a haze value of 80% (integrated type of light diffusion layer-base material layer, thickness 120 μm) was used as the light diffusion layer.

[Comparative Example 1]
A plurality of grooves formed on one surface side of the light transmission part using only a base layer of a PET film (A4100, light transmittance 92%, manufactured by Toyobo Co., Ltd.) having a thickness of 100 μm instead of the light diffusion layer A daylighting film was obtained in the same manner as in Example 1 except that instead of the air layer, a light deflecting portion constituting composition having the following composition was filled and cured to form a light polarizing portion.
(Light deflection unit composition)
42 parts by weight of urethane acrylate as the photocurable prepolymer (P3), 18 parts by weight of epoxy acrylate as the photocurable prepolymer (P4), 35 parts by weight of tripropylene glycol diacrylate as the reactive diluent monomer (M3), 5 parts by weight of methoxytriethylene glycol acrylate as the reactive diluent monomer (M4), 5 parts by weight of titanium dioxide P25 (average particle size 21 nm, manufactured by Nippon Aerosil Co., Ltd.) as the light diffusion particle (D1), a photopolymerization initiator ( 7 parts by weight of 1-hydroxycyclohexyl phenyl ketone (trade name: Irgacure 184, manufacturer name: BASF) was mixed and homogenized as I1) to prepare a light deflection unit composition.
The components excluding the light diffusing particles of the composition for constituting the light deflector are coated so as to have a thickness of 100 μm, and cured by irradiating with 800 mJ / cm ² of ultraviolet light with a high-pressure mercury lamp, and having a multi-wavelength Abbe refractive index. Using a meter (manufactured by Atago Co., Ltd.), the refractive index of 589 nm was measured and found to be 1.490.

[Comparative Example 2]
A daylighting film was obtained in the same manner as in Comparative Example 1 except that the matte film of Example 1 was used as the light diffusion layer instead of the base material layer.

[Comparative Example 3]
A daylighting film was obtained in the same manner as in Comparative Example 1 except that the matte film of Example 3 was used as the light diffusion layer instead of the base material layer.

[Evaluation]
The following evaluation was performed about the lighting film obtained by Examples 1-3 and Comparative Examples 1-3.
In the measurement of the total light transmittance and the evaluation of the light diffusibility, the incident surface of the daylighting film is the surface located on the surface side having the groove opening of the light control layer among the surfaces of the daylighting film (on the adhesive layer side of the daylighting film) Surface).

1. Measurement of total light transmittance The obtained daylighting film was measured using a haze meter HR100 (Murakami Color Research Laboratory Co., Ltd., JIS K7136: 1999 compliant method).

2. Light diffusivity evaluation About the obtained lighting film, diffusivity evaluation was performed with the following method.
Using a three-dimensional variable angle spectrocolorimetry system GCMS11 (Murakami Color Research Laboratory), light is incident on the daylighting film within an incident angle range of 20 ° to 60 °, and the incident light is incident on each incident angle. On the other hand, the emission angle (maximum peak emission angle) at which the peak intensity of light bounced up in the ceiling is maximized was specified. The measurement conditions and method are the same as those described in the section “I. Optical characteristics B. Light diffusibility”. In this evaluation, the incident angles are 20 °, 30 °, 40 °, 50 ° and 60 °. Measured as °. The maximum peak intensity of the outgoing light in each incident light is assumed to be 100%, and the measured intensity of the outgoing light received at the maximum peak outgoing angle ± 3 ° is converted into the converted intensity with respect to the maximum peak intensity (100%). The light diffusivity for incident light was used. Table 1 shows the minimum value of the light diffusivities determined for each incident angle as the light diffusivity of the daylighting film with respect to an incident angle of 20 ° to 60 °.

3. Privacy concealment evaluation The lighting films obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were attached to a window, and a subject was placed behind the window at a distance of 10 cm. The level at which the contour can be identified is indicated by ○, and the level at which the contour cannot be identified is indicated by ×. The subject used artificial flowers, and the image was taken with a camera from a distance of 45 cm from the daylighting film. The subjective evaluation has two directions: a case where an object on the outdoor side is observed from the indoor side through a window with a daylighting film and a case where an object on the indoor side is observed from the outdoor side via a window with a daylighting film. It was performed by observation.
The level at which the contour of the subject is indistinguishable is the level at which it is felt that the contour of the artificial petal cannot be recognized.

  Each evaluation result is shown in Table 1. Moreover, the picked-up image in privacy hiding evaluation of Examples 1-3 and the comparative example 1 is shown to FIG.11 (b)-(e) and FIG.12 (b)-(e). 11 is a photographed image when an object on the indoor side is observed from the outdoor side through a window with a daylighting film, and FIG. 12 is a photograph of an object on the outdoor side from the indoor side through a window with a daylighting film. It is a photographed image when observed. FIG. 11A and FIG. 12A are photographed images when an object is observed through a window without a daylighting film as a reference.

The daylighting films of Examples 1 to 3 having a light diffusivity with respect to an incident angle of 20 ° or more and 60 ° or less of 40% and a total light transmittance of 80% or more are both for daylighting and privacy hiding. It was possible to demonstrate high functions.
On the other hand, in Comparative Example 1 in which the light diffusivity was 40% or less, the contour of the subject could be determined, and the privacy hiding property could not be improved. Moreover, in the comparative examples 1-3 whose total light transmittance is less than 80% or more, sufficient lighting property was not acquired.

DESCRIPTION OF SYMBOLS 10 ... Daylighting member 1 ... Incident surface 2 ... Outgoing surface 3 ... Light reflection surface 4, 12 ... Light deflection part 20 ... Light control layer 22A, 22B, 22C ... Light diffusion layer

Claims (7)

An incident surface which is a surface on which light is incident;
An exit surface that is a surface on the side from which light is emitted and is opposite to the entrance surface;
A plurality of light reflecting surfaces disposed between the incident surface and the exit surface, and reflecting light incident from the entrance surface toward the exit surface;
A daylighting member having at least
The daylighting member has a total light transmittance of 80% or more, and
The intensity of the emitted light that is incident from the incident surface at an incident angle of 20 ° to 60 ° and is emitted from the output surface is measured, and the intensity of the emitted light corresponding to each incident angle is maximized. The emission angle is specified, and the intensity of the emission light within the range of the emission angle ± 3 ° when the maximum peak intensity of the emission light at the emission angle is 100% is 40% or more. A daylighting member. The daylighting member is a daylighting film having a light control layer, and a light diffusion layer disposed on one surface side of the light control layer,
The light control layer includes a light transmission portion made of a transparent resin, and a plurality of grooves having the light reflection surface formed on one surface of the light transmission portion,
The daylighting member according to claim 1, further comprising: a light deflecting portion formed in a plurality of the groove portions and having a refractive index different from that of the light transmitting portion.   The daylighting member according to claim 2, wherein the light diffusing layer is located closer to the light exit surface than the light control layer. A base material layer is disposed on one surface of the light control layer,
The daylighting member according to claim 2 or 3, wherein the light diffusion layer is integral with the base material layer. The daylighting member has a first glass layer, a first sealing portion, a light control layer, a second sealing portion, and a second glass layer in this order,
On one surface of the first glass layer or the second glass layer, a laminated glass in which a light diffusion layer is disposed,
The light control layer includes a light transmission portion made of a transparent resin, and a plurality of grooves having the light reflection surface formed on one surface of the light transmission portion,
The daylighting member according to claim 1, further comprising: a light deflecting portion formed in a plurality of the groove portions and having a refractive index different from that of the light transmitting portion.   The daylighting member according to claim 5, wherein the light diffusion layer is positioned closer to a light emission surface than the light control layer.   The daylighting member according to claim 5 or 6, wherein the light diffusion layer is integral with the first glass layer or the second glass layer.