JP2020086177A - Light adjustment unit, light adjustment member having light adjustment unit, and mobile body having light adjustment member - Google Patents

Abstract

To provide a light adjustment unit which has an increased weather resistance, a light adjustment member having the light adjustment unit, and a mobile body having the light adjustment member.SOLUTION: A light adjustment unit (3) includes: a first laminate body (31) having a first resin base material (311), a first electrode layer (314), and a first orientation film (315) in that order; a second laminate body (32) having a second resin base material (321), a second electrode layer (324), and a second orientation film (325) in that order, the second orientation film (325) facing the first orientation film (315); a liquid crystal layer (33) between the first orientation film (315) and the second orientation film (325), the liquid crystal layer containing a dichroic dye; and a seal material (34) between the first laminate body (31) and the second laminate body (32), the seal material surrounding the liquid crystal layer (33). At least one of the first orientation film (315) and the second orientation film (325) has a thickness of at least 100 nm.SELECTED DRAWING: Figure 5

Description

The present invention relates to a light control unit capable of adjusting light transmittance, a light control member including the light control unit, and a moving body including the light control member.

BACKGROUND ART Conventionally, a light control unit capable of adjusting the light transmittance and a light control member including the light control unit are known. As a method of adjusting the light transmittance of the light control unit, a method using liquid crystal is known.

Patent Document 1 has a first laminated body having a first resin base material, a first electrode layer and a first alignment film in order, a second resin base material, a second electrode layer and a second alignment film in order, A second laminate in which the second alignment film is arranged so as to face the first alignment film; a liquid crystal layer which is located between the first alignment film and the second alignment film and contains a dichroic dye; A dimming unit is described, which is located between the one laminated body and the second laminated body and includes a sealing material surrounding the liquid crystal layer. In the light control unit described in Patent Document 1, by applying a voltage to the first electrode layer and the second electrode layer, the alignment of liquid crystal molecules and dichroic dye in the liquid crystal material forming the liquid crystal layer is controlled, Can be adjusted.

JP, 2018-84621, A

The optical characteristics of the light control unit deteriorate with use. In particular, when the light control unit is used in an environment where external light such as sunlight is radiated, the optical characteristics of the light control unit are likely to deteriorate. Such deterioration of the optical characteristics of the light control unit is remarkable when the liquid crystal layer contains a dichroic dye. Therefore, it is required to improve the weather resistance of the light control unit.

Therefore, an object of the present invention is to provide a dimming unit having improved weather resistance, a dimming member including the dimming unit, and a moving body including the dimming member.

As a result of earnest research for solving the above problems, the present inventors have found that a first laminate having a first resin substrate, a first electrode layer, and a first alignment film in order, a second resin substrate, and a second resin substrate. A second laminate having an electrode layer and a second alignment film in this order, the second alignment film being arranged to face the first alignment film, and located between the first alignment film and the second alignment film. A first alignment film and a second alignment film in a light control unit including a liquid crystal layer containing a dichroic dye and a sealant located between the first laminate and the second laminate and surrounding the liquid crystal layer. It has been found that the thickness of the film affects the weather resistance of the light control unit. The present invention has been completed based on these findings and includes the following inventions.

[1] A first laminate having a first resin base material, a first electrode layer, and a first alignment film in order,
A second laminate having a second resin base material, a second electrode layer, and a second alignment film in order, and the second alignment film provided so as to face the first alignment film;
A liquid crystal layer located between the first alignment film and the second alignment film and containing a dichroic dye;
A sealant located between the first laminate and the second laminate and surrounding the liquid crystal layer;
A dimming unit comprising:
The light control unit, wherein one or both of the first alignment film and the second alignment film have a thickness of 100 nm or more.
[2] The light control unit according to [1], wherein both the first alignment film and the second alignment film have a thickness of 100 nm or more.
[3] The light control unit according to [1], wherein one or both of the first alignment film and the second alignment film have a thickness of 200 nm or more.
[4] The light control unit according to [3], wherein both the first alignment film and the second alignment film have a thickness of 200 nm or more.
[5] The first laminate has a refractive index smaller than the refractive index of the first hard coat layer and the first hard coat layer between the first resin substrate and the first electrode layer. 1. The light control unit according to any one of [1] to [4], which has 1 low refractive index layer in order.
[6] The first laminate has a first hard coat layer between the first resin base material and the first electrode layer, and a refractive index higher than the refractive index of the first hard coat layer. 1. A high refractive index layer, and a first low refractive index layer having a refractive index lower than that of the first high refractive index layer in order, [1] to [4] Light control unit.
[7] The second laminated body has a refractive index smaller than that of the second hard coat layer and the second hard coat layer between the second resin base material and the second electrode layer. 2. The light control unit according to any one of [1] to [6], which has two low refractive index layers in order.
[8] The second laminate has a second hard coat layer between the second resin base material and the second electrode layer, and a refractive index higher than the refractive index of the second hard coat layer. 2. A high refractive index layer, and a second low refractive index layer having a refractive index smaller than that of the second high refractive index layer in order, [1] to [6]. Light control unit.
[9] L ^* measured in a state in which a voltage is applied to the liquid crystal layer so that the light transmittance of the liquid crystal layer becomes the minimum or the maximum before the weather resistance test is performed on the light control unit ^. Let L ^* , a ^*, and b ^* of the a ^* b ^* color system be L ₁ ^* , a ₁ ^*, and b ₁ ^* , respectively, and after performing a weather resistance test on the light control unit under the following conditions, L ^* , a ^*, and b ^* of the L ^* a ^* b ^* color system, which are measured in a state where a voltage is applied to the liquid crystal layer so that the light transmittance of the liquid crystal layer is minimum or maximum, are respectively expressed by L ₂ ΔE=((L ₂ ^* -L ₁ ^* ) ² +(a ₂ ^* -a ₁ ^* ) ² +(b ₂ ^* -b ₁ ^* ) ² ) ^{1 where *} , a ₂ ^* and b ₂ ^{* The} light control sheet according to any one of [1] to [8], wherein the color difference ΔE defined by ^/2 is 3.0 or less.
[Conditions for weather resistance test]
・Weather resistance tester: Atlas Weatherometer CI4000
・Test time: 250 hours ・Light source: Xenon arc lamp ・Black panel temperature: 63±3℃
・Relative humidity: 50±5% (during irradiation)
・Sample surface irradiance: 60 W/m ² (continuous irradiation at 300 to 400 nm)
-Inner filter: Type S borosilicate-Outer filter: Type S borosilicate [10] The light control unit includes a spacer provided between the first laminated body and the second laminated body, [1] ~ The light control unit according to any one of [9].
[11] The light control unit according to any one of [1] to [10],
A light transmissive member laminated on the light control unit,
A light control member.

According to the present invention, there are provided a light control unit having improved weather resistance, a light control member including the light control unit, and a moving body including the light control member.

FIG. 1 is a diagram schematically showing a configuration of a light control device according to an embodiment of the present invention. FIG. 2 is a plan view of the light control member according to the embodiment of the present invention. 3 is a sectional view taken along the line AA of FIG. FIG. 4 is a plan view of the light control unit according to the embodiment of the present invention. FIG. 5 is a sectional view taken along line BB of FIG. FIG. 6 is a cross-sectional view for explaining a translucent state (a state in which light can be transmitted) of the light control unit according to the embodiment of the present invention. FIG. 7 is a cross-sectional view for explaining a light blocking state (a state where light transmission is blocked) of the light control unit according to the embodiment of the present invention. FIG. 8: is a perspective view which shows schematically the moving body provided with the light control member which concerns on one Embodiment of this invention. FIG. 9 is a view for explaining the method of manufacturing the light control unit according to the embodiment of the present invention. FIG. 10 is a diagram (continuation of FIG. 9) for explaining the method for manufacturing the light control unit according to the embodiment of the present invention. FIG. 11 is a diagram (continuation of FIG. 10) for explaining the method for manufacturing the light control unit according to the embodiment of the present invention. FIG. 12 is a diagram (continuation of FIG. 11) for explaining the method for manufacturing the light control unit according to the embodiment of the present invention. FIG. 13 is a diagram (continuation of FIG. 12) for explaining the method of manufacturing the light control unit according to the embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. It should be noted that, in the drawings, the scale, the vertical and horizontal dimensional ratios, etc. may be changed from the actual ones and exaggerated for convenience, in consideration of ease of illustration and understanding. Further, in the present specification, the terms “plate”, “sheet” and “film” are not distinguished from each other based only on the difference in designation. For example, the term “plate” is a concept that also includes members that can be called sheets or films. Further, terms used in the present specification to specify shapes, geometric conditions and their degrees (for example, terms such as “parallel”, “orthogonal” and “identical”, length, angle, etc.) are Without being limited to a strict meaning, it is construed as meaning a range in which substantially equivalent and similar functions can be expected.

[Dimmer]
FIG. 1 is a diagram schematically showing a configuration of a light control device 1 according to an embodiment of the present invention. As shown in FIG. 1, the light control device 1 includes a light control member 2 and a light control controller 4 electrically connected to the light control member 2. In the present embodiment, the sensor device 5 and the user operation unit 6 are electrically connected to the dimming controller 4.

[Light control member]
FIG. 2 is a plan view of the light control member 2 according to the embodiment of the present invention, and FIG. 3 is a sectional view taken along the line AA of FIG. 2 and 3, the wiring that electrically connects the light control member 2 and the light control controller 4 is omitted.

As shown in FIGS. 2 and 3, the light control member 2 has a longitudinal direction X, a lateral direction Y, and a thickness direction Z that are orthogonal to each other.

As shown in FIGS. 2 and 3, the light control member 2 includes a first light transmissive member 21, a second light transmissive member 22, a first light transmissive member 21, and a second light transmissive member 22. The light control unit 3 provided between the first light transmitting member 21 and the first light transmitting member 21, the second polarizing plate 23 provided between the light control unit 3, the second light transmitting member 22, and the light control unit 3 A second polarizing plate 24, a first bonding layer 25 for bonding the first light transmitting member 21 and the first polarizing plate 23, a second light transmitting member 22, and a second polarizing plate. And a second bonding layer 26 for bonding with 24.

Although the dimming member 2 actually has a three-dimensional curved surface, in FIGS. 2 and 3 the dimming member 2 is shown as a flat plate having a rectangular shape in plan view for convenience of understanding. ing. The shape of the light control member 2 can be appropriately changed. For example, the light control member 2 may be a flat plate having a rectangular shape in plan view, or may have a curved portion and/or a bent portion.

In the present embodiment, the light transmissive members are provided on both sides of the light control unit 3, but may be provided on only one side of the light control unit 3. That is, one of the first light transmissive member 21 and the second light transmissive member 22 can be omitted. Therefore, the present invention also includes an embodiment in which one of the first light transmissive member 21 and the second light transmissive member 22 is omitted.

In the present embodiment, the polarizing plates are provided on both sides of the dimming unit 3, but may be provided on only one side of the dimming unit 3, or may not be provided on both sides of the dimming unit 3. Good. That is, the first polarizing plate 23 and the second polarizing plate 24 are optional elements and can be omitted. Therefore, the present invention also includes an embodiment in which one or both of the first polarizing plate 23 and the second polarizing plate 24 are omitted. Whether or not a polarizing plate is used can be appropriately determined based on, for example, a liquid crystal material forming a liquid crystal layer 33 (described later) of the light control unit 3. In the present embodiment, the liquid crystal material forming the liquid crystal layer 33 contains a dichroic dye together with liquid crystal molecules, and a guest-host (GH) system is adopted. When the GH method is adopted, one or both of the first polarizing plate 23 and the second polarizing plate 24 can be omitted.

[Light-transmissive member]
The first light transmissive member 21 and the second light transmissive member 22 are not particularly limited as long as they have light transmissivity (preferably visible light transmissivity).

Examples of the material forming each of the first light transmissive member 21 and the second light transmissive member 22 include, for example, glass such as soda glass, soda lime glass, potash glass, and quartz glass; poly(meth)acrylate methyl, poly. Acrylic resins such as ethyl (meth)acrylate, butyl poly(meth)acrylate, ethylene-methyl (meth)acrylate copolymer, methyl (meth)acrylate-butyl (meth)acrylate copolymer; polycarbonate resins Etc. In addition, in this specification, (meth)acrylic acid means acrylic acid or methacrylic acid. The first light transmissive member 21 and the second light transmissive member 22 may be made of the same material or may be made of different materials. The first light transmissive member 21 and/or the second light transmissive member 22 may include a component that inhibits the transmission of ultraviolet rays (for example, an ultraviolet absorber). The surface of the first light transmissive member 21 and/or the second light transmissive member 22 may be provided with a functional layer such as a high-rigidity film (for example, a cycloolefin polymer layer) or a heat reflection film.

The first light-transmissive member 21 and the second light-transmissive member 22 actually have curved surfaces having a three-dimensional shape, but in FIGS. The transmissive member 21 and the second light transmissive member 22 are shown as flat plates each having a rectangular shape in plan view. The respective shapes of the first light transmissive member 21 and the second light transmissive member 22 can be appropriately changed. For example, the first light transmissive member 21 and/or the second light transmissive member 22 may be a flat plate having a rectangular shape in plan view, or may have a curved portion and/or a bent portion.

In a preferred embodiment, the first light transmissive member 21 and the second light transmissive member 22 are transparent members, for example, glass plates.

The thickness of each of the first light transmissive member 21 and the second light transmissive member 22 can be appropriately adjusted. The thickness of each of the first light transmissive member 21 and the second light transmissive member 22 is preferably 0.6 mm or more and 3.4 mm or less, more preferably 1.9 mm or more and 2.1 mm or less. The first light transmissive member 21 and the second light transmissive member 22 may have the same thickness or different thicknesses. When the thickness of each light transmissive member is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of each light transmissive member can be measured by observing a cross-section microscope.

[Polarizer]
As shown in FIG. 3, the first polarizing plate 23 is provided between the first light transmissive member 21 and the light control unit 3, and the second polarizing plate 24 is provided with the second light transmissive member 22. It is provided between the light control unit 3 and the light control unit 3. However, the first polarizing plate 23 and the second polarizing plate 24 are optional elements and can be omitted. Therefore, the present invention also includes an embodiment in which one or both of the first polarizing plate 23 and the second polarizing plate 24 are omitted. Whether or not the polarizing plate is used can be appropriately determined based on, for example, the driving method of the adopted liquid crystal molecules. For example, when the GH system is adopted, one or both of the first polarizing plate 23 and the second polarizing plate 24 can be omitted.

The first polarizing plate 23 and the second polarizing plate 24 each have an absorption axis and a polarization axis (transmission axis) orthogonal to the absorption axis. Each of the first polarizing plate 23 and the second polarizing plate 24 selectively absorbs one linearly polarized light component vibrating in a direction parallel to the absorption axis, and vibrates in a direction parallel to a transmission axis orthogonal to the absorption axis. It has a polarization function of selectively transmitting the other linearly polarized light component that is used. The first polarizing plate 23 and the second polarizing plate 24 each include, for example, a polarizer. The polarizer is configured so as to exhibit a desired polarization function, and is typically produced by stretching PVA (polyvinyl alcohol) doped with an iodine compound. Generally, when a polarizer is produced by stretching, the absorption axis of the polarizer is determined according to the stretching direction, and the polarizers stretched in the same direction have the same absorption axis. As arrangement modes of the first polarizing plate 23 and the second polarizing plate 24, a mode called “parallel nicol” in which the absorption axis of the first polarizing plate 23 and the absorption axis of the second polarizing plate 24 are parallel to each other, There is a mode called “crossed nicols” in which the absorption axis of the polarizing plate 23 and the absorption axis of the second polarizing plate 24 are perpendicular to each other.

[Joining layer]
As illustrated in FIG. 3, the first bonding layer 25 is provided between the first light transmissive member 21 and the first polarizing plate 23, and the first light transmissive member 21 and the first polarizing plate 23 are provided. And the second bonding layer 26 is provided between the second light transmitting member 22 and the second polarizing plate 24, and bonds the second light transmitting member 22 and the second polarizing plate 24. ..

In the embodiment in which the first polarizing plate 23 is omitted, the first bonding layer 25 is provided between the first light transmissive member 21 and the light control unit 3, and the first light transmissive member 21 and the light control unit are provided. Join 3 and. In the embodiment in which the second polarizing plate 24 is omitted, the second bonding layer 26 is provided between the second light transmissive member 22 and the light control unit 3, and the second light transmissive member 22 and the light control unit 3 are provided. Join 3 and.

The first bonding layer 25 and the second bonding layer 26 each have light transmissivity (preferably visible light transmissivity). The first bonding layer 25 and the second bonding layer 26 can be formed with an adhesive or a pressure-sensitive adhesive, respectively. Examples of the adhesive or pressure-sensitive adhesive include polyvinyl butyral type, urethane type, acrylic type, epoxy type, rubber type and polyolefin type. Examples of the polyolefin-based adhesive or pressure-sensitive adhesive include EVA (ethylene-vinyl acetate copolymer) and COP (cycloolefin polymer). The first bonding layer 25 and the second bonding layer 26 may be formed of the same adhesive or pressure-sensitive adhesive or different adhesives or pressure-sensitive adhesives. In a preferred embodiment, the first bonding layer 25 and the second bonding layer 26 are each made of a polyvinyl butyral adhesive.

The thickness of each of the first bonding layer 25 and the second bonding layer 26 can be appropriately adjusted. The thickness of each of the first bonding layer 25 and the second bonding layer 26 is preferably 0.01 mm or more and 5.2 mm or less, more preferably 0.4 mm or more and 3.5 mm or less. The first bonding layer 25 and the second bonding layer 26 may have the same thickness or different thicknesses. When the thickness of each bonding layer is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of each bonding layer can be measured by cross-sectional microscopic observation.

[Light control unit]
As shown in FIG. 3, the light control unit 3 is provided between the first light transmissive member 21 and the second light transmissive member 22, and imparts a light control function to the light control member 2. By applying a voltage from the external power source to the light control unit 3 (the first electrode layer 314 and the second electrode layer 324 of the light control unit 3), the light transmittance of the light control unit 3 (preferably visible light transmittance) Changes. That is, the state of the light control unit 3 changes between the first state in which the light transmittance is maximum and the second state in which the light transmittance is minimum. The light transmittance can be measured using a spectrophotometer (“UV-3100PC” manufactured by Shimadzu Corporation, JIS K 0115 compliant product). The visible light transmittance can be calculated as an average value of the transmittance of each wavelength when measured in the wavelength range of 380 nm to 780 nm.

FIG. 4 is a plan view of the light control unit 3 according to the embodiment of the present invention, and FIG. 5 is a sectional view taken along line BB of FIG. 4 and 5, the wiring that electrically connects the dimming unit 3 and the dimming controller 4 and the connecting portion of the dimming unit 3 that is connected to the wiring are omitted.

As shown in FIGS. 4 and 5, the dimming unit 3 has a longitudinal direction X, a lateral direction Y, and a thickness direction Z that are orthogonal to each other. The longitudinal direction, the lateral direction, and the thickness direction of the light control unit 3 correspond to the longitudinal direction, the lateral direction, and the thickness direction of the light control member 2, respectively.

As shown in FIGS. 4 and 5, the light control unit 3 has a sheet shape and preferably has flexibility.

As shown in FIGS. 4 and 5, the dimming unit 3 includes a first stacked body 31, a second stacked body 32, and a liquid crystal layer 33 located between the first stacked body 31 and the second stacked body 32. And a sealing material 34 located between the first stacked body 31 and the second stacked body 32 and surrounding the liquid crystal layer 33 in a circumferential shape, and located between the first stacked body 31 and the second stacked body 32. And a plurality of spacers 35.

In this specification, one of the pair of laminated bodies provided facing each other is referred to as a "first laminated body" and the other is referred to as a "second laminated body". The laminated body selected as the “first laminated body” may be any one of a pair of laminated bodies. In the present embodiment, the stacked body located on the upper side in FIG. 5 is selected as the “first stacked body”, but even if the stacked body located on the lower side in FIG. 5 is selected as the “first stacked body”. Good.

The light control unit 3 has improved weather resistance and can exhibit the following optical characteristics.

Before performing the weather resistance test on the light control unit 3, L ^* a ^* b measured with voltage applied to the liquid crystal layer 33 so that the light transmittance of the liquid crystal layer 33 becomes minimum or maximum. ^* L ^* , a ^*, and b ^* of the color system are L ₁ ^* , a ₁ ^*, and b ₁ ^* , respectively, and after performing a weather resistance test on the light control unit 3 under the following conditions, the liquid crystal layer 33 The L ^* a ^* b ^* color system L ^* , a ^*, and b ^* measured with a voltage applied to the liquid crystal layer 33 such that the light transmittance is minimum or maximum are L ₂ ^* , a, respectively. ₂ ^* and _b ^{2 *} and the time, at _{^{ΔE = ((L 2 * -L}} 1 *) 2 + (a 2 * -a 1 *) 2 + (b 2 * -b 1 *) 2) 1/2 The defined color difference ΔE (L ^* a ^* b ^* color difference (CIE1976) is preferably as small as possible (closer to 0). The color difference ΔE is preferably 3.0 or less, more preferably 2.5 or less, and even more preferably. Is 2.0 or less, and more preferably 1.8 or less.

L ₁ ^* , a ₁ ^* and b ₁ ^* are set so that the light transmittance of the liquid crystal layer 33 of the dimming unit 3 becomes the minimum or the maximum by using the dimming unit 3 before the weather resistance test. It is measured with a voltage applied to the liquid crystal layer 33. L ₂ ^* , a ₂ ^*, and b ₂ ^* are set so that the light transmittance of the liquid crystal layer 33 of the light control unit 3 becomes minimum or maximum by using the light control unit 3 after the weather resistance test. It is measured with a voltage applied to the liquid crystal layer 33.

The L ^* a ^* b ^* color system means a color system standardized by CIE (International Commission on Illumination) and adopted by JIS Z 8781-4:2013. In the L ^* a ^* b ^* color system, lightness is represented by L ^* , and chromaticity indicating hue and saturation is represented by a ^* and b ^* . L ^* a ^* b ^* color system of ^L *, ^{a *} and ^{b *,} JIS Z 8722: spectrophotometer conform to 2009 (for example, Otsuka Electronics RETS-1250VA) is measured using the. Specifically, light is emitted from the light source to the main surface of the light control unit 3, reflected light in the regular reflection direction is received by the detector, and the received reflected light is converted into the L ^* a ^* b ^* color system. L ^* , a ^* and b ^* are determined. The light irradiation is performed on the main surface of the light control unit 3 at an incident angle of 90 degrees (the normal direction of the main surface of the light control unit 3 is 0 degree). The main surface of the light control unit 3 to which the light is irradiated may be the main surface on the first stacked body 31 side or the main surface on the second stacked body 32 side. Examples of the light source include a tungsten halogen (WI) lamp alone, a combination of a deuterium (D2) lamp and a tungsten halogen (WI) lamp, and the like.

In the embodiment employing the normally white method, as will be described later, when sufficient voltage is applied to the first electrode layer 314 and the second electrode layer 324, the light transmission of the liquid crystal layer 33 of the dimming unit 3 is performed. Minimal rate. Therefore, in the embodiment in which the normally white method is adopted, the light transmittance of the liquid crystal layer 33 is minimum in L ₁ ^* , a ₁ ^* , b ₁ ^* , L ₂ ^* , a ₂ ^* , and b ₂ ^*. As described above, the measurement is performed while a sufficient voltage is applied to the first electrode layer 314 and the second electrode layer 324.

In the embodiment in which the normally black method is adopted, as will be described later, when a sufficient voltage is applied to the first electrode layer 314 and the second electrode layer 324, the liquid crystal layer 33 of the dimming unit 3 is not affected. Maximum light transmission. Therefore, in the embodiment in which the normally black method is adopted, L ₁ ^* , a ₁ ^* , b ₁ ^* , L ₂ ^* , a ₂ ^* , and b ₂ ^* have the maximum light transmittance of the liquid crystal layer 33. As described above, the voltage is applied to the first electrode layer 314 and the second electrode layer 324.

The conditions of the weather resistance test are as follows. The weather resistance test is performed in the state where no voltage is applied to the liquid crystal layer 33.
[Conditions for weather resistance test]
・Weather resistance tester: Atlas Weatherometer CI4000 (Distributor: Toyo Seiki Co., Ltd.)
・Test time: 250 hours ・Light source: Xenon arc lamp ・Black panel temperature: 63±3℃
・Relative humidity: 50±5% (during irradiation)
・Sample surface irradiance: 60 W/m ² (continuous irradiation at 300 to 400 nm)
・Inner filter: Type S borosilicate ・Outer filter: Type S borosilicate

[Laminate]
As shown in FIG. 5, the first stacked body 31 includes a first resin base material 311, a first electrode layer 314, and a first alignment film 315 in order.

As shown in FIG. 5, the first laminated body 31 includes the first hard coat layer 312 and the first low refractive index layer 313 between the first resin base material 311 and the first electrode layer 314. It is provided in order from the material 311 side. That is, the first stacked body 31 includes the first resin base material 311, the first hard coat layer 312, the first low refractive index layer 313, the first electrode layer 314, and the first alignment film 315 in this order. However, in the first laminated body 31, the first hard coat layer 312 and the first low refractive index layer 313 are optional elements and can be omitted. Therefore, the present invention also includes an embodiment in which one or both of the first hard coat layer 312 and the first low refractive index layer 313 are omitted in the first laminated body 31.

As shown in FIG. 5, the first stacked body 31 is provided on the other surface of the first resin base material 311 in addition to the first hard coat layer 312 provided on one surface of the first resin base material 311. And an additional hard coat layer 316. However, the additional hard coat layer 316 is an optional element and can be omitted. Therefore, the present invention also includes embodiments in which the additional hard coat layer 316 is omitted.

As shown in FIG. 5, the second stacked body 32 includes a second resin base material 321, a second electrode layer 324, and a second alignment film 325 in this order. As shown in FIG. 5, the second stacked body 32 is provided so that the second alignment film 325 faces the first alignment film 315.

As shown in FIG. 5, the second laminated body 32 includes the second hard coat layer 322 and the second low refractive index layer 323 between the second resin base material 321 and the second electrode layer 324. It is provided in order from the material 321 side. That is, the second stacked body 32 includes the second resin base material 321, the second hard coat layer 322, the second low refractive index layer 323, the second electrode layer 324, and the second alignment film 325 in this order. However, in the second laminated body 32, the second hard coat layer 322 and the second low refractive index layer 323 are optional elements and can be omitted. Therefore, the present invention also includes an embodiment in which one or both of the second hard coat layer 322 and the second low refractive index layer 323 are omitted in the second laminated body 32.

As shown in FIG. 5, the second laminated body 32 is provided on the other surface of the second resin base material 321 in addition to the second hard coat layer 322 provided on one surface of the second resin base material 321. And an additional hard coat layer 326. However, the additional hard coat layer 326 is an optional element and can be omitted. Therefore, the present invention also includes embodiments in which the additional hard coat layer 326 is omitted.

[Resin base material]
Each of the first resin base material 311 and the second resin base material 321 is a member for supporting a layer provided on the surface thereof. By using a resin base material instead of a glass base material, it is possible to realize a thin and lightweight structure. Further, by using the resin base material, the light control unit 3 can be provided with flexibility, and the light control unit 3 can have not only a two-dimensional curved surface shape but also a three-dimensional curved surface shape. Here, the two-dimensional curved surface means a curved surface that is two-dimensionally curved about a single axis, or a surface that is curved two-dimensionally with the same or different curvatures about a plurality of mutually parallel axes. To do. On the other hand, the three-dimensional curved surface means a surface that is partially or wholly bent around each of a plurality of non-parallel axis lines.

The first resin base material 311 and the second resin base material 321 each have a sheet shape and have light transmissivity (preferably visible light transmissivity). Each of the first resin base material 311 and the second resin base material 321 preferably has flexibility. In a preferred embodiment, the first resin base material 311 and the second resin base material 321 are transparent films. The first resin base material 311 and the second resin base material 321 may be made of the same synthetic resin, or may be made of different synthetic resins. Examples of the synthetic resin forming the first resin base material 311 and the second resin base material 321 include polyolefin resins such as polyethylene resin and polypropylene resin; polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl alcohol resin, vinyl chloride- Vinyl-based resins such as vinyl acetate copolymer resin, ethylene-vinyl acetate copolymer resin, ethylene-vinyl alcohol copolymer resin; polyethylene terephthalate resin, polypropylene terephthalate, polybutylene terephthalate resin, polyethylene naphthalate resin, ethylene naphthalate-isophthalate. Polyester resin such as copolymer resin; poly(meth)acrylic acid methyl resin, poly(meth)acrylic acid ethyl resin, poly(meth)butyl acrylate resin, etc. acrylic resin; nylon 6, nylon 66, etc. polyamide resin; Cellulose resins such as acetyl cellulose resins; aromatic polycarbonate resins based on bisphenols (bisphenol A, etc.), polycarbonate resins such as aliphatic polycarbonate resins such as diethylene glycol bisallyl carbonate, and the like.

The thickness of each of the first resin base material 311 and the second resin base material 321 can be appropriately adjusted. The thickness of each of the first resin base material 311 and the second resin base material 321 is preferably 23 μm or more and 250 μm or less, and more preferably 50 μm or more and 188 μm or less. When the thickness of each resin substrate is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of each resin substrate can be measured by observing a cross-section microscope.

The surface of the first resin base material 311 and/or the second resin base material 321 may be subjected to a physical or chemical surface treatment such as an oxidation method or a roughening method for the purpose of improving adhesion. Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone/ultraviolet treatment method, and the like, and examples of the roughening method include a sandblast method, a solvent treatment method, and the like.

An easy-adhesion layer may be formed on the surfaces of the first resin base material 311 and/or the second resin base material 321. Examples of the easily adhesive resin contained in the easily adhesive layer (sometimes referred to as a primer layer or an anchor layer) include acrylic resin, vinyl chloride-vinyl acetate copolymer, polyester resin, urethane resin, chlorinated polypropylene, and chlorine. And polyethylene.

[Hard coat layer]
The first hard coat layer 312, the second hard coat layer 322, and the additional hard coat layers 316 and 326 are 2B in the pencil hardness test (4.9 N load) defined by JIS K5600-5-4 (1999), respectively. It is a layer having the above hardness. The hardness of each hard coat layer can be appropriately adjusted in terms of scratch resistance required for the light control unit 3. The upper limit of the hardness of each hard coat layer is not particularly limited, but is usually about H.

The thickness of each of the first hard coat layer 312, the second hard coat layer 322 and the additional hard coat layers 316 and 326 can be appropriately adjusted. The thickness of each hard coat layer is preferably 0.5 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm or less. These hard coat layers may have the same thickness or different thicknesses. When the thickness of each hard coat layer is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of each hard coat layer can be measured by cross-sectional microscopic observation.

At least one of the first hard coat layer 312 and the second hard coat layer 322 may include high refractive index particles. Since the first hard coat layer 312 contains high refractive index particles, the first hard coat layer 312 can function as a high refractive index layer, and the first hard coat layer 312 can be indexed together with the first low refractive index layer 313. It can function as a matching layer. Similarly, since the second hard coat layer 322 contains high refractive index particles, the second hard coat layer 322 can function as a high refractive index layer, and the second hard coat layer 322 can be the second low refractive index layer. 323 and can function as an index matching layer. The high refractive index particles such as titanium oxide (TiO _2, refractive index: 2.3 to 2.7), niobium oxide _(Nb 2 _{O 5,} refractive index: 2.33), zirconium oxide (ZrO _2, refraction Ratio: 2.10), antimony oxide (Sb ₂ O ₅ , refractive index: 2.04), tin oxide (SnO ₂ , refractive index: 2.00), indium tin oxide (ITO, refractive index: 1.95 to 2.00), cerium oxide (CeO ₂ , refractive index: 1.95), aluminum-doped zinc oxide (AZO, refractive index: 1.90 to 2.00), gallium-doped zinc oxide (GZO, refractive index: 1.00). 90 to 2.00), zinc antimonate (ZnSb ₂ O _6, refractive index: 1.90 to 2.00), zinc oxide (ZnO, refractive index: 1.90), yttrium oxide _(Y 2 _{O 3,} the refractive Ratio: 1.87), antimony-doped tin oxide (ATO, refractive index: 1.75 to 1.85), phosphorus-doped tin oxide (PTO, refractive index: 1.75 to 1.85), and the like. Can be mentioned. The amount of high refractive index particles contained in the first hard coat layer 312 or the second hard coat layer 322 can be appropriately adjusted.

The first hard coat layer 312, the second hard coat layer 322, and the additional hard coat layers 316 and 326 can be made of resin, respectively. Each hard coat layer is formed by curing a composition containing an ionizing radiation curable resin (ionizing radiation curable resin composition), and preferably contains a cured product of an ionizing radiation curable resin.

[Ionizing radiation curable resin and ionizing radiation curable resin composition]
The following description of the ionizing radiation-curable resin and the ionizing radiation-curable resin composition, unless otherwise specified, only the ionizing radiation-curable resin and the ionizing radiation-curable resin composition used for forming the hard coat layer. However, it is also applied to ionizing radiation curable resins and ionizing radiation curable resin compositions used for forming other layers.

The ionizing radiation curable resin composition contains one or more ionizing radiation curable resins. The ionizing radiation curable resin composition is, for example, a mixture of a solid content such as an ionizing radiation curable resin and a solvent or a dispersion medium. Examples of the solvent or dispersion medium include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ethyl acetate, butyl acetate, 2-methoxyethyl acetate, and 2-ethoxy acetate. Ester-based organic solvents such as ethyl; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol; ketone-based organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone Solvents; ether organic solvents such as diethyl ether, dioxane, tetrahydrofuran; chlorine organic solvents such as dichloromethane, carbon tetrachloride, trichloroethylene, tetrachloroethylene; inorganic solvents such as water. As the solvent or dispersion medium, one type may be used alone, or two or more types may be used in combination.

The ionizing radiation curable resin is a resin that undergoes a cross-linking polymerization reaction upon irradiation with ionizing radiation and changes into a three-dimensional polymer structure. The ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking a molecule, and usually ultraviolet rays (UV) or electron beams (EB) are used, but other X Electromagnetic waves such as rays and γ rays, and charged particle rays such as α rays and ion rays are also included. Among the ionizing radiation curable resins, the electron beam curable resins are preferable because they can be solvent-free and stable curing characteristics can be obtained.

Examples of the ionizing radiation curable resin include, for example, a polymerizable unsaturated bond crosslinkable by irradiation with ionizing radiation (for example, an ethylenic double bond), a cationically polymerizable functional group (for example, a (meth)acryloyl group, a vinyl group, One or more types of monomers, oligomers, prepolymers and the like having an allyl group etc.) in the molecule can be used. In addition, in this specification, a "(meth)acryloyl group" means an acryloyl group or a methacryloyl group.

The weight average molecular weight of the monomer used as the ionizing radiation curable resin is, for example, less than 1,000. In addition, in this specification, a "weight average molecular weight" is a value measured by a gel permeation chromatography (GPC) method using polystyrene as a standard substance.

Examples of the above-mentioned monomer used as the ionizing radiation-curable resin include (meth)acrylate monomers having a radically polymerizable unsaturated group in the molecule and the like, and polyfunctional (meth)acrylate monomers are particularly preferable. In addition, in this specification, "(meth)acrylate" means an acrylate or a methacrylate.

The polyfunctional (meth)acrylate monomer is a (meth)acrylate monomer having two or more (two or more) polymerizable unsaturated bonds, preferably three or more (three or more functional) polymerizable unsaturated bonds in the molecule. Examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth). Acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth) Acrylate, ethylene oxide modified di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide modified trimethylolpropane tri(meth)acrylate, di Pentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, tris(acryloxyethyl)isocyanurate, propion Examples thereof include acid-modified dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethylene oxide-modified dipentaerythritol hexa(meth)acrylate, and caprolactone-modified dipentaerythritol hexa(meth)acrylate. The polyfunctional (meth)acrylates may be used alone or in combination of two or more. A monofunctional (meth)acrylate may be used together with the polyfunctional (meth)acrylate for the purpose of lowering the viscosity thereof.

The weight average molecular weight of the oligomer used as the ionizing radiation curable resin is, for example, 1,000 or more and less than 10,000. Examples of the above-mentioned oligomer used as the ionizing radiation-curable resin include (meth)acrylate oligomers having a radically polymerizable unsaturated group in the molecule, and particularly, two polymerizable unsaturated bonds are included in the molecule. A polyfunctional (meth)acrylate oligomer having the above (bifunctional or more) is preferable. Examples of the polyfunctional (meth)acrylate oligomer include polycarbonate (meth)acrylate, acrylic silicone (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate. , Polybutadiene (meth)acrylate, silicon (meth)acrylate, oligomers having a cationically polymerizable functional group in the molecule (for example, novolac type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.) and the like. ..

The weight average molecular weight of the prepolymer used as the ionizing radiation curable resin is, for example, 10,000 or more. The weight average molecular weight of the prepolymer is preferably 10,000 or more and 80,000 or less, more preferably 10,000 or more and 40,000 or less. Examples of the above-mentioned prepolymer used as the ionizing radiation curable resin include (meth)acrylate prepolymers having a radically polymerizable unsaturated group in the molecule, and particularly, a polymerizable unsaturated bond in the molecule. A polyfunctional (meth)acrylate prepolymer having two or more (bifunctional or more) is preferable. Examples of the polyfunctional (meth)acrylate prepolymer include polycarbonate (meth)acrylate, acrylic silicone (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, and polyether (meth). Acrylate, polybutadiene (meth)acrylate, silicon (meth)acrylate, oligomer having a cationically polymerizable functional group in the molecule (for example, novolac type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.) and the like. Be done.

Polycarbonate (meth)acrylate is not particularly limited as long as it has a carbonate bond in the polymer main chain and a (meth)acrylate group at the terminal or side chain. For example, polycarbonate polyol can be replaced with (meth)acrylic acid. It can be obtained by esterification. The polycarbonate (meth)acrylate may be, for example, urethane (meth)acrylate having a polycarbonate skeleton. The urethane (meth)acrylate having a polycarbonate skeleton is obtained, for example, by reacting a polycarbonate polyol, a polyvalent isocyanate compound, and a hydroxy (meth)acrylate. Acrylic silicone (meth)acrylate can be obtained by radically copolymerizing a silicone macromonomer with a (meth)acrylate monomer. The urethane (meth)acrylate can be obtained, for example, by esterifying a polyurethane oligomer obtained by reacting a polyether polyol or polyester polyol with a polyisocyanate with (meth)acrylic acid. Epoxy (meth)acrylate can be obtained by, for example, reacting (meth)acrylic acid with the oxirane ring of a bisphenol type epoxy resin or novolac type epoxy resin having a relatively low molecular weight to esterify. A carboxyl-modified epoxy (meth)acrylate obtained by partially modifying this epoxy (meth)acrylate with a dibasic carboxylic acid anhydride can also be used. Polyester (meth)acrylate is obtained, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of polyvalent carboxylic acid and polyhydric alcohol with (meth)acrylic acid It can be obtained by esterifying the terminal hydroxyl group of the oligomer obtained by adding alkylene oxide with (meth)acrylic acid. The polyether (meth)acrylate can be obtained by esterifying the hydroxyl group of the polyether polyol with (meth)acrylic acid. Polybutadiene (meth)acrylate can be obtained by adding (meth)acrylic acid to the side chain of a polybutadiene oligomer. Silicon (meth)acrylate can be obtained by adding (meth)(meth)acrylic acid to the terminal or side chain of silicon having a polysiloxane bond in the main chain.

The weight average molecular weight of the ionizing radiation curable resin is preferably 500 or more, more preferably 1000 or more. When the weight average molecular weight of the ionizing radiation curable resin is in the above range, a coating film of the ionizing radiation curable resin composition can be easily formed when the ionizing radiation curable resin composition is applied.

The weight average molecular weight of the ionizing radiation curable resin is preferably 80,000 or less, more preferably 50,000 or less. When the weight average molecular weight of the ionizing radiation curable resin is in the above range, the viscosity of the ionizing radiation curable resin composition can be easily adjusted to a viscosity suitable for coating.

The ionizing radiation curable resin is preferably at least one selected from polyfunctional monomers and oligomers having a weight average molecular weight of 500 or more. Examples of such polyfunctional monomers or oligomers include acrylate resins such as dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, urethane acrylate, polyester acrylate, and epoxy acrylate.

The ionizing radiation curable resin composition may optionally contain a component involved in the curing reaction of the ionizing radiation curable resin, for example, a photopolymerization initiator (sensitizer). For example, when the ionizing radiation-curable resin is cured by irradiation with ultraviolet rays, the ionizing radiation-curable resin composition preferably contains a photopolymerization initiator (sensitizer). Since the ionizing radiation curable resin is sufficiently cured by irradiation with an electron beam, when the ionizing radiation curable resin is cured by irradiation with an electron beam, the ionizing radiation curable resin composition contains a photopolymerization initiator (sensitizer). Agent) may not be included.

When the ionizing radiation curable resin has a radical polymerizable unsaturated group, as the photopolymerization initiator, for example, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, Michler benzoyl benzoate, Michler's ketone, diphenyl sulfide, At least one kind of dibenzyl disulfide, diethyl oxide, triphenylbiimidazole, isopropyl-N,N-dimethylaminobenzoate and the like can be used. When the ionizing radiation-curable resin has a cationically polymerizable functional group, examples of the photopolymerization initiator include aromatic diazonium salts, aromatic sulfonium salts, metallocene compounds, benzoin sulfonates, and fryloxysulfoxonium. At least one kind such as diallyl iodosyl salt can be used.

The amount of the photopolymerization initiator contained in the ionizing radiation curable resin composition is not particularly limited, but is usually 0.1 part by mass with respect to 100 parts by mass of the ionizing radiation curable resin contained in the ionizing radiation curable resin composition. It is above 10 parts by mass.

The ionizing radiation-curable resin composition is, if necessary, a solvent-drying resin (a thermoplastic resin or the like that forms a film by simply drying the solvent added to adjust the solid content during coating). , A thermosetting resin or the like may be included. By adding a solvent drying type resin to the ionizing radiation curable resin composition, it is possible to effectively prevent film defects on the coating surface of the ionizing radiation curable resin composition. As the solvent-drying resin, for example, a thermoplastic resin can be used, and as the thermoplastic resin, for example, a styrene resin, a (meth)acrylic resin, a vinyl acetate resin, a vinyl ether resin, a halogen-containing resin. , Alicyclic olefin resin, polycarbonate resin, polyester resin, polyamide resin, cellulose derivative, silicone resin and rubber or elastomer. As the thermosetting resin, for example, phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea co-condensation resin, silicon resin, Examples include polysiloxane resins and the like.

The ionizing radiation-curable resin composition is a dispersant, a surfactant, an antistatic agent, a silane cup for the purpose of increasing the hardness of the surface layer, suppressing curing shrinkage, adjusting the refractive index, etc., if necessary. Ring agent, thickener, anti-coloring agent, colorant (pigment, dye), defoaming agent, leveling agent, flame retardant, ultraviolet absorber, adhesion promoter, polymerization inhibitor, antioxidant, surface modifier, A slippery agent and the like may be included.

Formation of the layer using the ionizing radiation curable resin composition can be carried out as follows. Ionizing radiation curable resin composition is applied to the surface on which the layer is to be formed, and after the coating film of the ionizing radiation curable resin composition is dried, it is irradiated with ionizing radiation such as ultraviolet rays and electron beams to cure it. The resin composition is cured. As a result, a layer containing a cured product of the ionizing radiation curable resin is formed. Examples of the coating method include spin coating, dipping, spraying, slide coating, bar coating, roll coating, gravure coating, and die coating. When ultraviolet rays are used as the ionizing radiation, a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, and a metal halide lamp lamp can be used as the ultraviolet ray source. The wavelength of ultraviolet rays is usually 190 nm or more and 380 nm or less. When an electron beam is used as the ionizing radiation, the electron beam source may be, for example, a Cockcroft-Walt type, a Van de Graft type, a resonance transformer type, an insulating core transformer type, a linear type, a dynamitron type, a high frequency type electron. A linear accelerator can be used. The energy of the electron beam is usually 100 keV or more and 1000 keV or less, preferably 100 keV or more and 300 keV or less. The electron beam dose is usually 2 Mrad or more and 15 Mrad or less.

[Low refractive index layer]
As shown in FIG. 5, the first low refractive index layer 313 is provided between the first hard coat layer 312 and the first electrode layer 314. However, in the first stacked body 31, the first low refractive index layer 313 is an optional element and can be omitted. Therefore, the present invention also includes an embodiment in which the first low refractive index layer 313 is omitted in the first stacked body 31.

As shown in FIG. 5, the second low refractive index layer 323 is provided between the second hard coat layer 322 and the second electrode layer 324. However, in the second stacked body 32, the second low refractive index layer 323 is an optional element and can be omitted. Therefore, the present invention also includes an embodiment in which the second low refractive index layer 323 is omitted in the second stacked body 32.

The first low refractive index layer 313 has a refractive index lower than that of the first hard coat layer 312. The first low refractive index layer 313 preferably has a refractive index lower than that of the first electrode layer 314, and has a refractive index lower than that of the first resin base material 311 and the first electrode layer 314. Is more preferable. The second low refractive index layer 323 has a refractive index lower than that of the second hard coat layer 322. The second low refractive index layer 323 preferably has a refractive index lower than that of the second electrode layer 324, and has a refractive index lower than that of the second resin base material 321 and the second electrode layer 324. Is more preferable. The first low refractive index layer 313 and the second low refractive index layer 323 may have the same refractive index or may have different refractive indexes. The refractive index of the low refractive index layer is measured according to JIS K7142 (2008) when the low refractive index layer is present alone. The refractive index of the low refractive index layer can be measured by the same method as the refractive index of the hard coat layer.

The first low refractive index layer 313 and the second low refractive index layer 323 may each be composed of a single low refractive index layer, or may be composed of two or more low refractive index layers. .. When two or more low refractive index layers are provided, it is preferable to provide a difference in the refractive index and the thickness of each low refractive index layer.

The thickness of each of the first low refractive index layer 313 and the second low refractive index layer 323 can be appropriately adjusted. The first low refractive index layer 313 and the second low refractive index layer 323 may have the same thickness or different thicknesses. The thickness of each low refractive index layer is preferably 0.005 μm or more and 500 μm or less, more preferably 0.01 μm or more and 0.1 μm or less. When the thickness of each low refractive index layer is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of each low refractive index layer can be measured by observing a cross-section microscope.

Each of the first low refractive index layer 313 and the second low refractive index layer 323 can function as an index matching layer. Since the first low-refractive index layer 313 and the second low-refractive index layer 323 function as index matching layers, it is possible to reduce the visibility (so-called bone appearance phenomenon) of the first electrode layer 314 and the second electrode layer 324. it can.

The first low refractive index layer 313 and the second low refractive index layer 323 each include, for example, a binder resin and low refractive index particles dispersed in the binder resin. The first low-refractive index layer 313 and the second low-refractive index layer 323 are layers formed by curing a composition containing a curable resin and low-refractive index particles, respectively. Included as binder resin.

The shape of the low refractive index particles in a single particle state is preferably spherical. The spherical shape includes, for example, a true spherical shape and an elliptic spherical shape. The average particle diameter can be measured on a volume basis by a laser diffraction/scattering method according to JIS Z8825:2013. Examples of commercially available devices for measuring the volume-based particle size distribution by the laser diffraction/scattering method include a particle size distribution measuring device LS-230 manufactured by Beckman Coulter, Inc.

Examples of the low refractive index particles include silica particles and magnesium fluoride particles. The low refractive index particles may be used alone or in combination of two or more. The low refractive index particles may be solid particles or hollow particles. The low refractive index particles may have a photopolymerizable functional group on the surface. The low refractive index particles having such a photopolymerizable functional group on the surface can be produced by surface-treating the low refractive index particles with a silane coupling agent or the like. The amount of low refractive index particles contained in each of the first low refractive index layer 313 and the second low refractive index layer 323 can be appropriately adjusted.

The curable resin is preferably a thermosetting resin or an ionizing radiation curable resin, more preferably an ionizing radiation curable resin. That is, each of the first low refractive index layer 313 and the second low refractive index layer 323 preferably contains a cured product of a thermosetting resin or a cured product of an ionizing radiation curable resin, and the cured ionizing radiation curable resin. It is more preferable to include the thing. The low-refractive index particles may be present in the first low-refractive index layer 313 or the second low-refractive index layer 323 in a state of being combined with a cured product of a thermosetting resin or a cured product of an ionizing radiation curable resin.

Examples of the thermosetting resin include acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin.

The description of the ionizing radiation-curable resin is the same as the above description, and will be omitted.

The binder resin may be mixed with a resin having a low refractive index such as a resin having a fluorine atom introduced therein or an organopolysiloxane.

The first low refractive index layer 313 and the second low refractive index layer 323 include a thermosetting resin or an ionizing radiation curable resin, a solid content such as low refractive index particles (for example, silica particles), a solvent or a dispersion medium. It can be formed by a composition containing (a composition for forming a low refractive index layer). The description of the solvent or dispersion medium is the same as above, and will not be repeated. The low refractive index layer can be formed, for example, by the same method as the method for forming the hard coat layer. For example, the composition for forming a low refractive index layer is applied to the surface on which a layer is to be formed, the coating film of the composition for forming a low refractive index layer is dried, and then the composition for forming a low refractive index layer is cured. As a result, a layer containing a cured product of a thermosetting resin or a cured product of an ionizing radiation curable resin is formed.

The first low refractive index layer 313 and the second low refractive index layer 323 may be configured without using the low refractive index particles. The first low-refractive index layer 313 and the second low-refractive index layer 323 are, for example, a fluororesin, a low-refractive index resin such as organopolysiloxane, a low-refractive index substance such as silica or magnesium fluoride, or a combination thereof. And the like.

[Electrode layer]
As shown in FIG. 5, the first electrode layer 314 is provided closer to the first resin base material 311 than the first alignment film 315, and the second electrode layer 324 is second to the second alignment film 325. It is provided on the resin base material 321 side. In the present embodiment, the peripheral portion of the first electrode layer 314 is covered with the first alignment film 315, and the end portion of the sealing material 34 on the first electrode layer 314 side is fixed to the first alignment film 315. There is. Similarly, the peripheral portion of the second electrode layer 324 is covered with the second alignment film 325, and the end portion of the sealing material 34 on the second electrode layer 324 side is fixed to the second alignment film 325. However, the peripheral portion of the first electrode layer 314 is exposed from the first alignment film 315 (that is, not covered with the first alignment film 315), and the end of the sealing material 34 on the first electrode layer 314 side. The part may be fixed to the peripheral part of the first electrode layer 314. Similarly, the peripheral portion of the second electrode layer 324 is exposed from the second alignment film 325 (that is, not covered with the second alignment film 325), and the second electrode layer 324 side of the sealing material 34 is provided. The end portion may be fixed to the peripheral portion of the second electrode layer 324.

The first electrode layer 314 and the second electrode layer 324 are, for example, transparent conductive layers. The first electrode layer 314 and the second electrode layer 324 are, for example, an inorganic transparent conductive layer material, an organic transparent conductive layer material, or an inorganic transparent conductive layer material and an organic transparent conductive material, respectively. It can be formed of a mixed material with a layer material. Examples of the inorganic transparent conductive layer material include indium tin oxide (ITO), antimony-doped tin oxide (ATO), zinc oxide, indium oxide (In ₂ O ₃ ), aluminum-doped zinc oxide (AZO), and gallium-doped. Examples thereof include zinc oxide (GZO), tin oxide, zinc oxide-tin oxide-based, indium oxide-tin oxide-based, zinc oxide-indium oxide-magnesium oxide-based metal oxides, and carbon nanotubes. In a preferred embodiment, the first electrode layer 314 and the second electrode layer 324 each include indium tin oxide (ITO).

The first electrode layer 314 and the second electrode layer 324 are connected to the dimming controller 4 via, for example, FPCs (Flexible Printed Circuits). The arrangement mode of the first electrode layer 314 and the second electrode layer 324 is not particularly limited. Each of the first electrode layer 314 and the second electrode layer 324 may be arranged only at a predetermined position by patterning, or may be arranged on the entire surface. An electric field acting on the liquid crystal layer 33 disposed between the first electrode layer 314 and the second electrode layer 324 is formed according to the voltage applied to the first electrode layer 314 and the second electrode layer 324, and the liquid crystal layer The alignment of the liquid crystal molecules and the dichroic dye in the liquid crystal material constituting 33 is adjusted.

The refractive index of each of the first electrode layer 314 and the second electrode layer 324 is preferably 1.5 or more and 2.5 or less, more preferably 1.5 or more and 2.0 or less. The first electrode layer 314 and the second electrode layer 324 may have the same refractive index or different refractive indexes. The refractive index of the electrode layer is measured according to JIS K7142 (2008) when the electrode layer is present alone. The refractive index of the electrode layer can be measured by the same method as the refractive index of the hard coat layer.

The thickness of each of the first electrode layer 314 and the second electrode layer 324 can be appropriately adjusted. The first electrode layer 314 and the second electrode layer 324 may have the same thickness or different thicknesses. The thickness of each electrode layer is preferably 10 nm or more and 100 nm or less, more preferably 20 nm or more and 50 nm or less. When the thickness of each electrode layer is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of each electrode layer can be measured by cross-sectional microscopic observation.

[Alignment film]
As shown in FIG. 5, the first alignment film 315 and the second alignment film 325 are adjacent to the liquid crystal layer 33, respectively, and control the alignment of liquid crystal molecules in the liquid crystal material forming the liquid crystal layer 33. The method for producing the alignment film is not particularly limited. The first alignment film 315 and the second alignment film 325 having liquid crystal alignment ability can be manufactured by an arbitrary method. For example, the alignment film may be prepared by subjecting a resin layer such as polyimide to a rubbing treatment, or the polymer film may be irradiated with linearly polarized ultraviolet light to selectively react polymer chains in the polarization direction. The alignment film may be produced based on the alignment method. Instead of the alignment film and the photo-alignment film formed by such a rubbing treatment, the fine line-shaped unevenness formed by the rubbing treatment may be formed by a shaping process to produce the alignment film.

One or both of the first alignment film 315 and the second alignment film 325 has a thickness of 100 nm or more. The thickness of one or both of the first alignment film 315 and the second alignment film 325 is preferably 150 nm or more, more preferably 200 nm or more. When one of the first alignment film 315 and the second alignment film 325 has a thickness of 100 nm or more, preferably 150 nm or more, more preferably 200 nm or more, the other thickness can be appropriately adjusted, but preferably 100 nm or more, The thickness is more preferably 150 nm or more, still more preferably 200 nm or more. That is, the thickness of both the first alignment film 315 and the second alignment film 325 is preferably 100 nm or more, more preferably 150 nm or more, and even more preferably 200 nm or more. The first alignment film 315 and the second alignment film 325 may have the same thickness or different thicknesses. When the thickness of the alignment film is not constant, the average value of the thickness of the alignment film is adopted as the thickness of the alignment film. Specifically, 30 locations separated from each other in a plan view of the light control unit 3 are selected, and the thickness of the alignment film at each location is measured from an image obtained by imaging a cross section at each location with a scanning electron microscope (SEM). The average value of the measured thicknesses at 30 points is adopted as the thickness of the alignment film.

The upper limits of the thicknesses of the first alignment film 315 and the second alignment film 325 can be adjusted as appropriate, but if the thickness is too large, it becomes difficult to manufacture the alignment film. The thickness of the alignment film 325 is preferably 300 nm or less, more preferably 220 nm or less.

When the thickness of one or both of the first alignment film 315 and the second alignment film is 100 nm or more, the weather resistance of the liquid crystal layer 33 can be improved, and thus the weather resistance of the light control unit 3 is improved. be able to. The effects of the first alignment film 315 and the second alignment film 325 increase as the thicknesses of the first alignment film 315 and the second alignment film 325 increase. The light control unit 3 can exhibit the above-mentioned optical characteristics by having improved weather resistance. When the thickness of one or both of the first alignment film 315 and the second alignment film is 200 nm or more, it is possible to prevent dynamic scattering caused by applying a voltage (for example, 8 V).

It is considered that gas is generated from the constituent elements of the first stacked body 31 as the dimming unit 3 is used, and the gas enters the liquid crystal layer 33 to deteriorate the liquid crystal layer 33. When the thickness of the first alignment film 315 is 100 nm or more, the first alignment film 315 can prevent gas generated from the constituent elements of the first stacked body 31 from entering the liquid crystal layer 33. It is considered that the weather resistance of the liquid crystal layer 33 can be improved. It is considered that the gas adsorption ability of the first alignment film 315 is involved in the effect of the first alignment film 315. The component capable of generating gas is, for example, a component containing a synthetic resin. The 1st laminated body 31 has the 1st resin base material 311, the 1st hard coat layer 312, the 1st low refractive index layer 313, and the additional hard coat layer 316 as a component containing a synthetic resin. As described above, the first hard coat layer 312, the first low-refractive index layer 313, and the additional hard coat layer 316 are optional elements and can be omitted. However, the first hard coat layer 312 does not generate gas. The more components that can be obtained, the more remarkable the effect exhibited by the thickness of the first alignment film 315 being 100 nm or more. Therefore, the first stacked body 31 preferably includes one or more of the first hard coat layer 312, the first low refractive index layer 313, and the additional hard coat layer 316.

It is considered that gas is generated from the constituent elements of the second stacked body 32 as the dimming unit 3 is used, and the gas enters the liquid crystal layer 33 to deteriorate the liquid crystal layer 33. When the thickness of the second alignment film 325 is 100 nm or more, the second alignment film 325 can prevent the gas generated from the components of the second stacked body 32 from entering the liquid crystal layer 33. It is considered that the weather resistance of the liquid crystal layer 33 can be improved. It is considered that the gas adsorption ability of the second alignment film 325 is involved in the effect of the second alignment film 325. The component capable of generating gas is, for example, a component containing a synthetic resin. The second laminated body 32 has a second resin base material 321, a second hard coat layer 322, a second low refractive index layer 323, and an additional hard coat layer 326 as constituent elements containing a synthetic resin. As described above, the second hard coat layer 322, the second low refractive index layer 323, and the additional hard coat layer 326 are optional elements and can be omitted, but the gas generating gas included in the second laminate 32 is generated. The more components that can be used, the more remarkable the effect exhibited by the thickness of the second alignment film 325 being 100 nm or more. Therefore, the second laminated body 32 preferably includes one or more of the second hard coat layer 322, the second low refractive index layer 323, and the additional hard coat layer 326.

[Liquid crystal layer]
As shown in FIG. 5, the liquid crystal layer 33 is provided between the first alignment film 315 of the first stacked body 31 and the second alignment film 325 of the second stacked body 32. The liquid crystal layer 33 is a guest-host (GH) type liquid crystal layer, and the liquid crystal material forming the liquid crystal layer 33 contains a dichroic dye (guest) and liquid crystal molecules (host). In the embodiment in which the liquid crystal layer 33 is the GH type, one or both of the first polarizing plate 23 and the second polarizing plate 24 can be omitted.

The dichroic dye is a dye having a property that the absorbance in the major axis direction of the molecule and the absorbance in the minor axis direction are different. The dichroic dye preferably has a characteristic of absorbing desired visible light, and more preferably has a maximum absorption wavelength (λMAX) in the range of 380 to 680 nm. Examples of dichroic dyes include acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes, and anthraquinone dyes. A preferred dichroic dye is an azo dye. Examples of azo dyes include monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes and stilbeneazo dyes. The dichroic dyes may be used alone or in combination of two or more. For example, in order to block the entire visible light, it is preferable to use two or more dichroic dyes in combination, and it is more preferable to use three or more dichroic dyes in combination.

The thickness of the liquid crystal layer 33 can be adjusted appropriately. The thickness of the liquid crystal layer 33 is preferably 2 μm or more and 15 μm or less, more preferably 5 μm or more and 10 μm or less. When the thickness of the liquid crystal layer 33 is not constant, both the minimum thickness and the maximum thickness are preferably within the above range. The thickness of the liquid crystal layer 33 can be measured by observing a cross-section microscope.

The orientation of the liquid crystal molecules and the dichroic dye contained in the liquid crystal material forming the liquid crystal layer 33 is determined by the voltage applied to the first electrode layer 314 and the second electrode layer 324 from the external power source (for example, the dimming controller 4). And the light transmittance of the liquid crystal layer 33 changes accordingly. That is, the state of the liquid crystal layer 33 changes between the first state in which the light transmittance is maximum and the second state in which the light transmittance is minimum.

The method of changing the light transmittance of the liquid crystal layer 33 may be a normally white type or a normally black type. The normally white method is a method in which the light transmittance is maximum when no voltage is applied, and the light transmittance decreases when a voltage is applied. The normally black method is a method in which the light transmittance is minimum when no voltage is applied, and the light transmittance increases when a voltage is applied.

When the normally white method is adopted, as will be described later, when the voltage between the pair of transparent electrodes (first electrode layer 314 and second electrode layer 324) is ON, the dichroic dye 331 and the liquid crystal 222 are used. Need to be aligned in a direction (horizontal direction) perpendicular to the thickness direction Z of the light control unit 3, so that vertical alignment films are used as the first alignment film 315 and the second alignment film 325, and negative liquid crystal is used as liquid crystal molecules. Molecules are used.

When the normally black method is adopted, as will be described later, when the voltage between the pair of transparent electrodes (the first electrode layer 314 and the second electrode layer 324) is ON, the dichroic dye 331 and the liquid crystal molecules are Since it is necessary to align 332 in the direction parallel to the thickness direction Z of the light control unit 3 (vertical direction), horizontal alignment films are used as the first alignment film 315 and the second alignment film 325, and positive type liquid crystal molecules are used. Liquid crystal molecules are used.

The mechanism by which the light transmittance of the liquid crystal layer 33 changes will be described below with reference to FIGS. 6 and 7. FIG. 6 is a cross-sectional view for explaining a light-transmitting state of the light control unit 3, and FIG. 7 is a cross-sectional view for explaining a light-blocking state of the light control unit 3. Note that, in FIGS. 6 and 7, the dichroic dye and the liquid crystal molecules are conceptually shown in order to facilitate understanding of the alignment directions of the dichroic dye and the liquid crystal molecules.

As shown in FIGS. 6 and 7, the liquid crystal layer 33 includes a dichroic dye 331 and liquid crystal molecules 332. The dichroic dye 331 exists in the liquid crystal molecules 332 in a dispersed state, has the same orientation as the liquid crystal molecules 332, and is basically arranged in the same direction as the liquid crystal molecules 332.

In the embodiment in which the normally white method is adopted, the voltage between the pair of transparent electrodes (the first electrode layer 314 and the second electrode layer 324) is OFF (that is, from the external power source (for example, the dimming controller 4)). When a voltage is not applied to the first electrode layer 314 and the second electrode layer 324), a desired electric field is not applied to the liquid crystal layer 33, and the dichroic dye 331 and the liquid crystal molecule 332 are shown in FIG. As described above, the light control units 3 are arranged in a direction parallel to the thickness direction Z (vertical direction). Therefore, the light incident on the liquid crystal layer 33 (light traveling in the direction from the second alignment film 325 side to the first alignment film 315 side or from the first alignment film 315 side to the second alignment film 325 side) is The light-shielding performance of the chromatic dye 331 is not exerted so much regardless of the vibration direction of light, and light entering the liquid crystal layer 33 passes through the liquid crystal layer 33 (dichroic dye 331 and liquid crystal molecules 332) with high probability. ..

In the embodiment in which the normally white method is adopted, the voltage between the pair of transparent electrodes (the first electrode layer 314 and the second electrode layer 324) is ON (that is, from the external power source (for example, the dimming controller 4)). When a voltage is applied to the first electrode layer 314 and the second electrode layer 324), a desired electric field is applied to the liquid crystal layer 33, and the dichroic dye 331 and the liquid crystal molecules 332 are generated as shown in FIG. Further, the light control units 3 are arranged in a direction (horizontal direction) perpendicular to the thickness direction Z. Therefore, the light entering the liquid crystal layer 33 (light traveling in the direction from the second alignment film 325 side to the first alignment film 315 side or in the direction from the first alignment film 315 side to the second alignment film 325 side) is The light is blocked (absorbed) by the dichroic dye 331. The orientation of the dichroic dye 331 and the liquid crystal molecules 332 in a state where a voltage is applied is preferably twisted by 180 degrees or more with respect to the horizontal direction, and the dichroic dye 331 is preferably oriented in all horizontal directions.

In the embodiment in which the normally black method is adopted, the voltage between the pair of transparent electrodes (the first electrode layer 314 and the second electrode layer 324) is OFF (that is, from the external power source (for example, the dimming controller 4)). When a voltage is not applied to the first electrode layer 314 and the second electrode layer 324), a desired electric field is not applied to the liquid crystal layer 33, and the dichroic dye 331 and the liquid crystal molecule 332 are shown in FIG. Thus, the light control units 3 are arranged in a direction (horizontal direction) perpendicular to the thickness direction Z. Therefore, the light entering the liquid crystal layer 33 (light traveling in the direction from the second alignment film 325 side to the first alignment film 315 side or in the direction from the first alignment film 315 side to the second alignment film 325 side) is The light is blocked (absorbed) by the dichroic dye 331. The orientation of the dichroic dye 331 and the liquid crystal molecules 332 in the state where no voltage is applied is preferably twisted by 180 degrees or more with respect to the horizontal direction, and the dichroic dye 331 is preferably oriented in all horizontal directions.

In the embodiment in which the normally black method is adopted, the voltage between the pair of transparent electrodes (the first electrode layer 314 and the second electrode layer 324) is ON (that is, from the external power source (for example, the dimming controller 4)). When a voltage is applied to the first electrode layer 314 and the second electrode layer 324), a desired electric field is applied to the liquid crystal layer 33, and the dichroic dye 331 and the liquid crystal molecules 332 are generated as shown in FIG. Further, the light control units 3 are arranged in a direction parallel to the thickness direction Z (vertical direction). Therefore, the light incident on the liquid crystal layer 33 (light traveling in the direction from the second alignment film 325 side to the first alignment film 315 side or from the first alignment film 315 side to the second alignment film 325 side) is The light-shielding performance of the chromatic dye 331 is not exerted so much regardless of the vibration direction of light, and light entering the liquid crystal layer 33 passes through the liquid crystal layer 33 (dichroic dye 331 and liquid crystal molecules 332) with high probability. ..

In the embodiment in which the first polarizing plate 23 is provided, of the light that has passed through the liquid crystal layer 33 (light that travels in the direction from the second alignment film 325 side to the first alignment film 315 side), the first polarization plate Light oscillating in parallel with the polarization axis (transmission axis) of 23 (light oscillating in a direction perpendicular to the absorption axis direction of the first polarizing plate 23) passes through the first polarizing plate 23 and is emitted from the light control unit 3. To do.

In the embodiment in which the second polarizing plate 24 is provided, the second polarizing plate out of the light that has passed through the liquid crystal layer 33 (light traveling in the direction from the first alignment film 315 side to the second alignment film 325 side). Light oscillating in parallel with the polarization axis (transmission axis) of 24 (light oscillating in a direction perpendicular to the absorption axis direction of the second polarizing plate 24) passes through the second polarizing plate 24 and is emitted from the light control unit 3. To do.

In the embodiment in which the first polarizing plate 23 is provided, the dichroic dye 331 and the liquid crystal molecules 332 are in a direction parallel to the thickness direction Z of the light control unit 3 (vertical direction), and When arranged in a direction parallel to the polarization axis of the plate 23 (direction perpendicular to the absorption axis direction of the first polarizing plate 23), light vibrating in the direction orthogonal to the absorption axis direction of the first polarizing plate 23 is dichroic. The dye 331 can block light, and the light vibrating in other directions can be blocked by the first polarizing plate 23. Therefore, light that has entered the light control unit 3 (light traveling in the direction from the second alignment film 325 side to the first alignment film 315 side) can be blocked by the dichroic dye 331 and the first polarizing plate 23. it can.

In the embodiment in which the second polarizing plate 24 is provided, the dichroic dye 331 and the liquid crystal molecules 332 are in the direction parallel to the thickness direction Z of the light control unit 3 (vertical direction), and the second polarized light is used. When aligned in a direction parallel to the polarization axis of the plate 24 (direction perpendicular to the absorption axis direction of the second polarizing plate 24), the light vibrating in the direction orthogonal to the absorption axis direction of the second polarizing plate 24 is dichroic. The dye 331 can block light, and the light vibrating in other directions can be blocked by the second polarizing plate 24. Therefore, light that has entered the light control unit 3 (light traveling in the direction from the first alignment film 315 side to the second alignment film 325 side) can be blocked by the dichroic dye 331 and the second polarizing plate 24. it can.

As described above, by controlling the voltage applied to the first electrode layer 314 and the second electrode layer 324, the light transmittance (preferably visible light transmittance) of the liquid crystal layer 33 can be changed. The light transmittance (preferably visible light transmittance) of the light control unit 3 can be changed.

[Seal material]
As shown in FIGS. 4 and 5, the sealing material 34 is provided between the first stacked body 31 and the second stacked body 32, and surrounds the liquid crystal layer 33 in a circumferential shape. That is, the sealant 34 partitions the liquid crystal layer 33 filled with the liquid crystal material. The sealing material 34 plays a role of preventing the liquid crystal material forming the liquid crystal layer 33 from leaking out from the light control unit 3, and also has the first stacked body 31 (the first alignment film 315) and the second stacked body 32 (the second stacked body 32. The two alignment films 325) are joined to play a role of fixing the two to each other.

The sealing material 34 is preferably formed by curing a composition containing a thermosetting resin (thermosetting resin composition), and contains a cured product of the thermosetting resin. As the thermosetting resin, for example, epoxy resin, phenol resin, unsaturated imide resin, cyanate resin, isocyanate resin, benzoxazine resin, oxetane resin, amino resin, unsaturated polyester resin, allyl resin, dicyclopentadiene resin, silicone Resin, triazine resin, melamine resin, etc. are mentioned. The thermosetting resins may be used alone or in combination of two or more. Among thermosetting resins, epoxy resins are preferable because they are excellent in moldability and electric insulation. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin. , Stilbene type epoxy resin, triazine skeleton containing epoxy resin, fluorene skeleton containing epoxy resin, triphenolphenolmethane type epoxy resin, biphenyl type epoxy resin, xylylene type epoxy resin, biphenylaralkyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene Examples thereof include diglycidyl ether compounds of type epoxy resins, alicyclic epoxy resins, polyfunctional phenols, and polycyclic aromatics such as anthracene. Moreover, you may use the phosphorus containing epoxy resin which introduced the phosphorus compound into these epoxy resins.

The amount of the thermosetting resin contained in the thermosetting resin composition can be appropriately adjusted according to the characteristics required of the sealing material 34 and the like. The thermosetting resin composition, in addition to the thermosetting resin, a curing agent, a curing accelerator, a thermoplastic resin, an elastomer, a flame retardant, an ultraviolet absorber, an antioxidant, a photopolymerization initiator, a fluorescent whitening agent, Adhesion improvers and the like can be added. When an epoxy resin is used as the thermosetting resin, examples of the curing agent include polyfunctional phenol compounds such as phenol novolac and cresol novolac; amine compounds such as dicyandiamide, diaminodiphenylmethane and diaminodiphenylsulfone; phthalic anhydride and pyropyrolic anhydride. Acid anhydrides such as meritic acid, maleic anhydride, and maleic anhydride copolymers; polyimides and the like. When an epoxy resin is used as the thermosetting resin, examples of the curing accelerator include imidazoles and their derivatives; organic phosphorus compounds; secondary amines, tertiary amines, and quaternary ammonium salts. Can be mentioned. Examples of the ultraviolet absorber include benzotriazole type and the like. Examples of the antioxidant include hindered phenol type and styrenated phenol type. Examples of the photopolymerization initiator include benzophenones, benzyl ketals, thioxanthones and the like. Examples of the fluorescent whitening agent include stilbene derivatives and the like. Examples of the adhesion improver include urea compounds such as urea silane and silane coupling agents.

In a preferred embodiment, the sealing material 34 includes a cured product of epoxy resin. In particular, when the liquid crystal material filling method between the first laminated body 31 and the second laminated body 32 is a vacuum injection method, it is preferable to use an epoxy resin sealing material as the sealing material 34. When the ODF (One Drop Fill) method is used as the filling method of the liquid crystal material, the sealing material 34 is formed by using a hybrid type material having both thermosetting property and UV curing property (ultraviolet curing property). Preferably. This is because the touch of the liquid crystal material with the sealing material before curing induces a defect in appearance. Therefore, it is preferable that the material forming the sealing material 34 includes an ultraviolet curable acrylic resin and an epoxy resin.

The thickness of the sealing material 34 can be appropriately adjusted. The thickness of the sealing material 34 is preferably 2 μm or more and 30 μm or less, more preferably 5 μm or more and 10 μm or less. When the thickness of the sealing material 34 is not constant, the maximum thickness is preferably within the above range. The thickness of the seal material 34 can be measured by observing a cross-section microscope.

[Spacer]
The spacer 35 is disposed between the first alignment film 315 of the first stacked body 31 and the second alignment film 325 of the second stacked body 32, and the space between the first alignment film 315 and the second alignment film 325. Stipulate. The spacer 35 secures a space between the first stacked body 31 and the second stacked body 32. The liquid crystal layer 33 is formed by filling the space with the liquid crystal material. Since the liquid crystal layer 33 controls the amount of phase modulation of transmitted light, the liquid crystal layer 33 needs to have a certain degree of constant thickness between the first stacked body 31 and the second stacked body 32. Further, the plurality of spacers 35 are discretely arranged between the first stacked body 31 and the second stacked body 32. Each spacer 35 can be made of various resin materials, and in this embodiment, a bead spacer is used as the spacer 35. The bead spacer has a spherical shape. The spherical shape includes, for example, a true spherical shape and an elliptic spherical shape. Each spacer 35 may have a shape such as a truncated cone (for example, a truncated cone or a truncated pyramid). The bead-shaped spacer may be applied by being dispersed in liquid crystal or alignment film ink in addition to the spraying method. Each spacer 35 can be formed at a desired position by using a photolithography technique,

[Dimming controller, sensor device and user operation unit]
As shown in FIG. 1, a sensor device 5 and a user operation unit 6 are connected to the dimming controller 4. The dimming controller 4 controls the dimming state of the dimming unit 3, switches between transmission and blocking of light by the dimming unit 3, and changes the transmittance (transmittance) of light passing through the dimming unit 3. You can Specifically, the dimming controller 4 adjusts the voltage applied to the liquid crystal layer 33 through the first electrode layer 314 and the second electrode layer 324 of the dimming unit 3 to align the liquid crystal molecules in the liquid crystal layer 33. By changing it, it is possible to switch between blocking and transmitting light by the light control unit 3 and changing the light transmittance.

The dimming controller 4 can adjust the voltage applied to the liquid crystal layer 33 based on any method. The dimming controller 4 adjusts the voltage applied to the liquid crystal layer 33 based on, for example, the measurement result of the sensor device 5 or an instruction (command) input by the user via the user operation unit 6, and adjusts the voltage. It is possible to switch between blocking and transmitting light by the optical unit 3 and changing the light transmittance. Therefore, the dimming controller 4 may automatically adjust the voltage applied to the liquid crystal layer 33 according to the measurement result of the sensor device 5, or according to the user's instruction via the user operation unit 6. You may adjust manually. Note that the measurement target by the sensor device 5 is not particularly limited, and for example, the brightness of the usage environment may be the measurement target. In this case, switching of light blocking and transmission by the light control unit 3 or light transmittance is performed. Is changed according to the brightness of the usage environment. Further, both the sensor device 5 and the user operation unit 6 do not necessarily need to be connected to the dimming controller 4, and only one of the sensor device 5 and the user operation unit 6 may be connected. Good.

In the light control device 1 configured as described above, a voltage is applied from the light control controller 4 to the light control member 2 through wiring such as FPC (Flexible Printed Circuits). The electric field acting on the liquid crystal layer 33 of the light control unit 3 changes according to the level of the voltage applied to the first electrode layer 314 and the second electrode layer 324 of the light control unit 3, and the liquid crystal forming the liquid crystal layer 33 is changed. The alignment of liquid crystal molecules and dichroic dyes in the material is adjusted. In this way, the light control device 1 can change the transmittance of light (especially visible light) that passes through the light control unit 3. For example, by adjusting the transmittance of light that passes through the light control unit 3, it is possible to transmit outside light such as sunlight with an appropriate amount of light or to block outside light such as sunlight.

Therefore, the light control device 1 can be applied to various technical fields in which adjustment of the transmittance of light (especially visible light) is required, and the applicable range is not particularly limited. The light control device 1 can be applied to various devices that require switching between light transmission and light shielding, such as windows of moving bodies, windows of buildings, showcases, and partitions arranged in a room.

[Mobile]
In one embodiment of the present invention, the light control device 1 is applied to a moving body. Examples of the moving body to which the light control device 1 can be applied include an automobile, an airplane, a ship, and a train. When the light control device 1 is applied to a moving body, for example, the window of the moving body can be configured by the light control member 2.

FIG. 8 is a diagram schematically showing an automobile 100 as an example of a moving body equipped with the light control device 1. In the embodiment shown in FIG. 8, the sunroof of the automobile 100 is composed of the light control member 2. In the automobile 100, other windows (for example, a rear window, a side window, etc.) of the automobile 100 may be configured by the light control member 2 instead of the sunroof or in addition to the sunroof. In the automobile 100, for example, a voltage can be applied to the first electrode layer 314 and the second electrode layer 324 of the light control unit 3 from a power source such as a battery (not shown) via a wiring.

[Method of manufacturing light control unit]
Hereinafter, an embodiment of a method of manufacturing the light control unit 3 will be described with reference to FIGS. 9 to 13. 9 to 13 are views for explaining the method for manufacturing the light control unit according to the embodiment of the present invention.

First, as shown in FIGS. 9 and 10, a first substrate 30a and a second substrate 30b are prepared. As shown in FIG. 9, the first substrate 30 a includes a precursor 31 ′ of the first stacked body 31 and a plurality of spacers 35 provided on the precursor 31 ′ of the first stacked body 31. The first stacked body 31 is formed by trimming the precursor 31 ′ of the first stacked body 31. As shown in FIG. 10, the second substrate 30 b includes a precursor 32 ′ of the second stacked body 32 and a plurality of spacers 35 provided on the precursor 32 ′ of the second stacked body 32. The second laminated body 32 is formed by trimming the precursor 32 ′ of the second laminated body 32. In the present embodiment, both the first substrate 30a and the second substrate 30b have the spacer 35, but only one of the first substrate 30a and the second substrate 30b may have the spacer 35.

The first substrate 30a can be manufactured, for example, as follows. First, the first hard coat layer 312 is formed on one surface of the first resin base material 311, and the additional hard coat layer 316 is formed on the other surface of the first resin base material 311. The first hard coat layer 312 and the additional hard coat layer 316 were respectively formed by applying the ionizing radiation curable resin composition onto the first resin base material 311 and drying the coating film of the ionizing radiation curable resin composition. Then, it can be formed by irradiating ionizing radiation such as ultraviolet rays or electron beams to cure the ionizing radiation curable resin composition. Then, the first low refractive index layer 313 is formed on the first hard coat layer 312. The first low refractive index layer 313 is a composition containing a thermosetting resin or an ionizing radiation curable resin, a solid content such as low refractive index particles (for example, silica particles), and a solvent or a dispersion medium (low refractive index. (Layer forming composition) is applied on the first hard coat layer 312, the coating film of the low refractive index layer forming composition is dried, and then the low refractive index layer forming composition is cured. be able to. Then, a first electrode layer 314 is formed on the first low refractive index layer 313 by sputtering or the like. Next, the spacers 35 are sprinkled on the first electrode layer 314. Then, the composition for forming the first alignment film 315 is applied on the first electrode layer 314 on which the spacers 35 are scattered, and the coating film is dried. In the present embodiment, the coating film is formed so that the peripheral portion of the first electrode layer 314 is covered with the composition for forming the first alignment film 315, but the peripheral portion of the first electrode layer 314 is formed. The coating film may be formed so as not to be covered with the composition for forming the first alignment film 315 (that is, the peripheral portion of the first electrode layer 314 is exposed). The coating amount of the composition for forming the first alignment film 315 is adjusted so that the thickness of the first alignment film 315 is 100 nm or more. By adjusting the solid content of polyimide or the like contained in the composition for forming the first alignment film 315, the viscosity of the composition, the thickness of the coating film of the composition, and the like can be adjusted. Note that the spacer 35 may be dispersed in the composition for forming the first alignment film 315, and the composition containing the spacer 35 may be dispersed over the first electrode layer 314. Then, an alignment regulating force is applied to the coating film by rubbing, photo-alignment or the like to form the first alignment film 315. In this way, the first substrate 30a is manufactured.

The second substrate 30b can be manufactured, for example, as follows. First, the second hard coat layer 322 is formed on one surface of the second resin base material 321, and the additional hard coat layer 326 is formed on the other surface of the second resin base material 321. The second hard coat layer 322 and the additional hard coat layer 326 were respectively formed by applying the ionizing radiation curable resin composition onto the second resin base material 321 and drying the coating film of the ionizing radiation curable resin composition. Then, it can be formed by irradiating ionizing radiation such as ultraviolet rays or electron beams to cure the ionizing radiation curable resin composition. Next, the second low refractive index layer 323 is formed on the second hard coat layer 322. The second low refractive index layer 323 is a composition (low refractive index) containing a thermosetting resin or an ionizing radiation curable resin, a solid content such as low refractive index particles (for example, silica particles), and a solvent or a dispersion medium. Layer forming composition) is applied on the second hard coat layer 322, the coating film of the low refractive index layer forming composition is dried, and then the low refractive index layer forming composition is cured. be able to. Then, a second electrode layer 324 is formed on the second low refractive index layer 323 by sputtering or the like. Next, the spacers 35 are dispersed on the second electrode layer 324. Next, the composition for forming the second alignment film 325 is applied on the second electrode layer 324 on which the spacers 35 are scattered, and the coating film is dried. In the present embodiment, the coating film is formed so that the peripheral portion of the second electrode layer 324 is covered with the composition for forming the second alignment film 325, but the peripheral portion of the second electrode layer 324 is formed. The coating film may be formed so that it is not covered with the composition for forming the second alignment film 325 (that is, the peripheral portion of the second electrode layer 324 is exposed). The coating amount of the composition for forming the second alignment film 325 is adjusted so that the thickness of the second alignment film 325 is 100 nm or more. By adjusting the solid content of polyimide or the like contained in the composition for forming the second alignment film 325, the viscosity of the composition, the thickness of the coating film of the composition, and the like can be adjusted. Note that the spacer 35 may be dispersed in the composition for forming the second alignment film 325, and the composition containing the spacer 35 may be dispersed over the second electrode layer 324. Next, an alignment control force is applied to the coating film by rubbing, photo-alignment, etc., so that the second alignment film 325 is formed. In this way, the second substrate 30b is manufactured.

Next, as shown in FIG. 11, the sealing material 34 ′ is circumferentially applied on the second alignment film 325. The sealing material 34' is a viscous liquid material having adhesiveness or tackiness, and the sealing material 34 is formed by curing the sealing material 34'. In the present embodiment, the sealing material 34 ′ is applied on the second alignment film 325, but the peripheral portion of the second electrode layer 324 is not covered with the composition for forming the second alignment film 325 (that is, When the peripheral portion of the second electrode layer 324 is exposed), the sealing material 34′ may be circumferentially applied to the peripheral portion of the second electrode layer 324. Further, in the present embodiment, the seal material 34' is applied on the second alignment film 325, but the seal material 34' may be applied circumferentially on the first alignment film 315 of the first substrate 30a.

Next, as shown in FIG. 12, a liquid crystal material 33' containing liquid crystal molecules and a dichroic dye is supplied to the region of the second substrate 30b surrounded by the seal material 34'. When applying the sealing material 34' to the first substrate 30a, the liquid crystal material 33' containing liquid crystal molecules and dichroic dye is supplied to the region of the first substrate 30a surrounded by the sealing material 34'. ..

Next, as shown in FIG. 13, the first substrate 30a and the second substrate 30b are stacked under reduced pressure, for example. A roller or the like may be used to squeeze the first substrate 30a and the second substrate 30b together. In the stacked body 3′ of the first substrate 30a and the second substrate 30b, there is a space secured by the spacer 35 between the first substrate 30a and the second substrate 30b, and the space is filled. The liquid crystal material 33 ′ forms the liquid crystal layer 33.

Next, the laminated body 3'of the first substrate 30a and the second substrate 30b is subjected to ultraviolet irradiation and/or heat treatment. As a result, the sealing material 34 ′ is deformed and hardened to become the sealing material 34, and the first substrate 30 a and the second substrate 30 b are joined by the sealing material 34.

Through the above steps, between the first substrate 30a, the second substrate 30b, the liquid crystal layer 33 located between the first substrate 30a and the second substrate 30b, and between the first substrate 30a and the second substrate 30b. A precursor of the dimming unit 3 including a sealing material 34 that is located and surrounds the liquid crystal layer 33 and a spacer 35 provided between the first substrate 30a and the second substrate 30b is prepared.

Then, the first substrate 30a and the second substrate 30b are partially cut from the precursor of the light control unit 3, and the outer peripheries of the first substrate 30a and the second substrate 30b, which are extra regions, are removed (that is, the first substrate 30a and the second substrate 30b). The substrate 30a and the second substrate 30b are trimmed). A part of the sealing material 34 may be cut and removed by trimming. The trimming of the first substrate 30a and the second substrate 30b can be performed using a tool including a punching blade, a cutter, and the like. By trimming, the first substrate 30a becomes the first stacked body 31 and the second substrate 30b becomes the second stacked body 32. When a part of the sealing material 34 is also cut by the trimming, the ends of the sealing material 34 coincide with the peripheral edge of the first stacked body 31 and the peripheral edge of the second stacked body 32 in a plan view. In this way, the light control unit 3 is manufactured. In the manufactured dimming unit 3, by applying a voltage from the external power supply (for example, the dimming controller 4) to the first electrode layer 314 and the second electrode layer 324, liquid crystal molecules and dichroic dye in the liquid crystal layer 33 are applied. The orientation of can be controlled. By changing the orientations of the liquid crystal molecules and the dichroic dye, the phase modulation amount of light when passing through the liquid crystal layer 33 changes. Thereby, the transmittance of the light transmitted through the first stacked body 31, the liquid crystal layer 33, and the second stacked body 32 can be changed.

In the light control member 2, the first bonding layer 25 and the first light transmissive member 21 are sequentially stacked on the side of the first stacked body 31 of the light control unit 3, and the first bonding layer 25 causes the light control unit 3 and the first light transmission member 21 to be stacked. While bonding the transmissive member 21, the second bonding layer 26 and the second light transmissive member 22 are sequentially stacked on the second laminated body 32 side of the dimming unit 3, and the dimming unit 3 is formed by the second bonding layer 26. It can be manufactured by bonding and the second light transmissive member 22.

Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to the above-described embodiments, and may include various aspects with various modifications that can be conceived by those skilled in the art. However, the effects achieved by the present invention are not limited to the above effects. Therefore, various additions, changes and partial deletions can be made to each element described in the claims and the specification without departing from the technical idea and gist of the present invention. It is also possible to appropriately combine two or more selected from the embodiments described in this specification.

For example, a high refractive index layer can be provided between the first hard coat layer 312 and the first low refractive index layer 313 and/or between the second hard coat layer 322 and the second low refractive index layer 323. .

The high refractive index layer (hereinafter referred to as “first high refractive index layer”) provided between the first hard coat layer 312 and the first low refractive index layer 313 has a refractive index higher than that of the first hard coat layer 312. It is a layer having a large refractive index. When the first high refractive index layer is provided between the first hard coat layer 312 and the first low refractive index layer 313, the first low refractive index layer 313 is smaller than the refractive index of the first high refractive index layer. It only needs to have a refractive index, and it is not always necessary to have a refractive index smaller than that of the first hard coat layer 312.

The high refractive index layer (hereinafter referred to as “second high refractive index layer”) provided between the second hard coat layer 322 and the second low refractive index layer 323 has a refractive index higher than that of the second hard coat layer 322. It is a layer having a large refractive index. When the second high refractive index layer is provided between the second hard coat layer 322 and the second low refractive index layer 323, the second low refractive index layer 323 is smaller than the refractive index of the second high refractive index layer. It only needs to have a refractive index, and it is not always necessary to have a refractive index smaller than that of the second hard coat layer 322.

The first high refractive index layer and the second high refractive index layer may each be composed of a single high refractive index layer, or may be composed of two or more high refractive index layers. When two or more high refractive index layers are provided, it is preferable to provide a difference in the refractive index and thickness of each high refractive index layer.

The thickness of each of the first high refractive index layer and the second high refractive index layer can be appropriately adjusted. The first high refractive index layer and the second high refractive index layer may have the same thickness or different thicknesses.

The first high refractive index layer and the second high refractive index layer can each function as an index matching layer. Since the first high refractive index layer and the second high refractive index layer function as index matching layers, the visibility (so-called bone appearance phenomenon) of the first electrode layer 314 and the second electrode layer 324 can be reduced.

The first high refractive index layer and the second high refractive index layer each include, for example, a binder resin and high refractive index particles dispersed in the binder resin. The first high-refractive index layer and the second high-refractive index layer are layers formed by curing a composition containing a curable resin and high-refractive index particles, respectively, and a cured product of the curable resin is a binder resin. Including as.

As the high refractive index particles, titanium oxide (TiO ₂ , refractive index: 2.3 to 2.7), niobium oxide (Nb ₂ O ₅ , refractive index: 2.33), zirconium oxide (ZrO ₂ , refractive index: 2.10), antimony oxide (Sb ₂ O ₅ , refractive index: 2.04), tin oxide (SnO ₂ , refractive index: 2.00), tin-doped indium oxide (ITO, refractive index: 1.95 to 2. 00), cerium oxide (CeO ₂ , refractive index: 1.95), aluminum-doped zinc oxide (AZO, refractive index: 1.90 to 2.00), gallium-doped zinc oxide (GZO, refractive index: 1.90 to 2.00), zinc antimonate (ZnSb ₂ O _6, refractive index: 1.90 to 2.00), zinc oxide (ZnO, refractive index: 1.90), yttrium oxide _(Y 2 _{O 3,} the refractive index: 1.87), antimony-doped tin oxide (ATO, refractive index: 1.75 to 1.85), phosphorus-doped tin oxide (PTO, refractive index: 1.75 to 1.85), and the like. The amount of high refractive index particles contained in each of the first high and low refractive index layers and the second high refractive index layer can be adjusted as appropriate.

The curable resin is preferably a thermosetting resin or an ionizing radiation curable resin, more preferably an ionizing radiation curable resin. That is, it is preferable that the first high refractive index layer and the second high refractive index layer each include a cured product of a thermosetting resin or a cured product of an ionizing radiation curable resin. It is more preferable to include.

Examples of the thermosetting resin include acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin.

The description of the ionizing radiation-curable resin is the same as the above description, and will be omitted.

The first high refractive index layer and the second high refractive index layer are a composition containing a thermosetting resin or an ionizing radiation curable resin, a solid content such as high refractive index particles, and a solvent or a dispersion medium (high refractive index It can be formed by a layer forming composition). The description of the solvent or dispersion medium is the same as above, and will not be repeated. The high refractive index layer can be formed, for example, by the same method as the method for forming the hard coat layer. For example, the composition for forming a high refractive index layer is applied to the surface on which a layer is to be formed, the coating film of the composition for forming a high refractive index layer is dried, and then the composition for forming a high refractive index layer is cured. As a result, a layer containing a cured product of a thermosetting resin or a cured product of an ionizing radiation curable resin is formed.

[Examples 1 to 3 and Comparative Example 1]
1. Manufacture of Light Control Unit The following steps were performed to manufacture a light control unit having a configuration similar to that shown in FIGS. 4 and 5.

(1) Preparation of laminated body As the first laminated body and the second laminated body, a laminated body provided with a hard coat layer, a resin base material, a hard coat layer, a low refractive index layer and an electrode layer in this order was used. The resin base material is a polyethylene terephthalate resin base material. The hard coat layer contains a cured product of an ionizing radiation curable resin as a main component, and contains high refractive index particles (ZrO ₂ particles) and the like as other components. The low refractive index layer contains a cured product of an ionizing radiation curable resin as a binder resin, and contains silica particles or a SiO ₂ film as another component. The electrode layer is a layer (ITO layer) made of indium tin oxide.

(2) Formation of Spacer A spacer was formed on the electrode layer of the second stacked body.

(3) Formation of Alignment Film An alignment film was formed on the electrode layer of the first laminated body and the electrode layer of the second laminated body. Regarding the second laminated body, after forming the spacer on the electrode layer of the second laminated body, the alignment film was formed on the electrode layer of the second laminated body. The alignment film was formed by thin film coating. The composition for forming an alignment film contains a thermosetting resin. The thermosetting resin contained in the composition for forming an alignment film is, for example, a polyimide resin such as soluble polyimide or polyamic acid, or an acrylic resin.

The solid content in the composition for forming an alignment film is 0.5% (Comparative Example 1), 1.0% (Example 1), 1.5% (Example 2), 2.0% (Example 3). The thickness of the alignment film was adjusted to 50 nm (Comparative Example 1), 100 nm (Example 1), 150 nm (Example 2), and 200 nm (Example 3) by adjusting the above.

(4) Formation of Seal Material A seal material (thickness: 30 μm, width: 5 mm) was applied to the peripheral portion of the alignment film of the second laminate.

(5) Supply of liquid crystal material The liquid crystal material was supplied to the area surrounded by the seal material.

(6) Curing of sealing material After the first laminate and the second laminate are laminated under reduced pressure so that the alignment film of the first laminate and the alignment film of the second laminate face each other, ultraviolet irradiation and Heat treatment was performed to deform and cure the sealing material.

Through the above steps, the light control unit shown in FIGS. 4 and 5 was manufactured. The manufactured dimming unit employs a normally white method, and when no voltage is applied to the electrode layers of the first laminate and the electrode layers of the second laminate, the liquid crystal layer of the dimming unit is used. Has the maximum light transmittance, and when a sufficient voltage is applied to the electrode layer of the first stacked body and the electrode layer of the second stacked body, the light transmittance of the liquid crystal layer of the light control unit becomes the minimum.

2. Weather resistance test A weather resistance test was performed on the light control unit. The weather resistance test was carried out in the state where no voltage was applied to the liquid crystal layer.
The conditions of the weather resistance test are as follows.
・Weather resistance tester: Atlas Weatherometer CI4000 (Distributor: Toyo Seiki Co., Ltd.)
・Test time: 250 hours ・Light source: Xenon arc lamp ・Black panel temperature: 63±3℃
・Relative humidity: 50±5% (during irradiation)
・Sample surface irradiance: 60 W/m ² (continuous irradiation at 300 to 400 nm)
・Inner filter: Type S borosilicate ・Outer filter: Type S borosilicate

3. Measurement of optical characteristics The optical characteristics are measured in a state where a voltage is applied to the liquid crystal layer to minimize the light transmittance of the liquid crystal layer before or after the weather resistance test is performed on the light control unit (first The voltage applied to the electrode layer of the laminated body and the electrode layer of the second laminated body was measured at 7V). In the measurement in the state where the light transmittance of the liquid crystal layer is the minimum (the state in which the voltage applied to the electrode layer of the first laminate and the electrode layer of the second laminate is 7V), the weather resistance test time is set to 250 hours. .. The measured optical properties are total light transmittance, haze, and L ^* , a ^* and b ^* of the L ^* a ^* b ^* color system.

[Total light transmittance]
The measuring method of the total light transmittance is as follows.
The measurement was performed with HM-150 (manufactured by Murakami Color Co., Ltd.).
The sample was set in the folder provided and the measurement was performed according to JIS K7361.

[Haze]
The haze measurement method is as follows.
The measurement was performed with HM-150 (manufactured by Murakami Color Co., Ltd.).
The sample was set in the folder provided and the measurement was performed according to JIS K 7136.

[L ^* a ^* b ^* L ^* , a ^* and b ^{* of} color system]
The L ^* a ^* b ^* colorimetric system L ^* , a ^* and b ^* are measured by the following method.
The measurement was performed with RETS-1250VA (manufactured by Otsuka Electronics Co., Ltd.).
The sample was set at a predetermined position and the spectroscopic spectrum/chromaticity was measured.

[Color difference ΔE]
Before carrying out the weather resistance test on the light control unit, L ^* a ^* b ^* color system L ^* , a ^* and b ^* measured respectively in a state where the light transmittance of the liquid crystal layer is minimum. L ₁ ^* , a ₁ ^*, and b ₁ ^*, and L ^* a ^* b ^* colorimetric values measured in a state where the light transmittance of the liquid crystal layer was minimum after a weather resistance test was performed on the light control unit. systems ^L *, ^{a *} and ^{b *,} respectively _L ² _*, when the _a ^{2 *} and _{^{b 2 *, ΔE = ((}} L 2 * -L 1 *) 2 + (a 2 * -a 1 *) ^The color difference ΔE defined by 2+(b ₂ ^* −b ₁ ^* ) ² ) ^1/2 is measured in the state where the light transmittance of the liquid crystal layer is minimum, and L of the L ^* a ^* b ^* color system is measured. Calculated based on ^* , a ^* and b ^* .

4. Presence or absence of occurrence of dynamic scattering Before and after performing a weather resistance test on the light control unit, a voltage of 8 V or 10 V is applied to the electrode layer of the first laminate and the electrode layer of the second laminate, The presence or absence of occurrence of dynamic scattering was evaluated. The presence or absence of occurrence of dynamic scattering was evaluated by applying a voltage to the light control unit in steps of 1 V and observing with a microscope.

Table 1 shows the measurement results in the state where the light transmittance of the liquid crystal layer is minimum (the state in which the voltage applied to the electrode layer of the first laminate and the electrode layer of the second laminate is 7V). The dynamic scattering did not occur when the thickness of the alignment film was 200 nm (Example 3) and the applied voltage was 8 V, but it occurred in other cases.

As shown in Table 1, by adjusting the thickness of the alignment film to 100 nm or more (Examples 1 to 3), the weather resistance of the light control unit can be improved and the optical characteristics of the light control unit can be maintained. found. As shown in Table 1, the dimming unit (Comparative Example 1) in which the thickness of the alignment film is 50 nm and the weather resistance is not improved, and the thickness of the alignment film is 100 nm or more, and the weather resistance is improved. The difference in color difference ΔE between the light control units (Examples 1 to 3) was remarkable in the state where the light transmittance of the liquid crystal layer was minimum (applied voltage 7V).

DESCRIPTION OF SYMBOLS 1 Light control device 2 Light control member 3 Light control unit 4 Light control controller 5 Sensor device 6 User operation part 21 1st light transmissive member 22 2nd light transmissive member 23 1st polarizing plate 24 2nd polarizing plate 25 1st Bonding layer 26 Second bonding layer 31 First laminated body 32 Second laminated body 33 Liquid crystal layer 34 Sealing material 35 Spacer 100 Moving body (automobile)
311 First resin base material 312 First hard coat layer 313 First low refractive index layer 314 First electrode layer 315 First alignment film 316 Additional hard coat layer 321 Second resin base material 322 Second hard coat layer 323 Second Low refractive index layer 324 Second electrode layer 325 Second alignment film 326 Additional hard coat layer

Claims (11)

A first laminate having a first resin substrate, a first electrode layer, and a first alignment film in that order;
A second laminate having a second resin base material, a second electrode layer, and a second alignment film in order, and the second alignment film provided so as to face the first alignment film;
A liquid crystal layer located between the first alignment film and the second alignment film and containing a dichroic dye;
A sealant located between the first laminate and the second laminate and surrounding the liquid crystal layer;
A dimming unit comprising:
The light control unit, wherein one or both of the first alignment film and the second alignment film have a thickness of 100 nm or more. The light control unit according to claim 1, wherein both the first alignment film and the second alignment film have a thickness of 100 nm or more. The light control unit according to claim 1, wherein one or both of the first alignment film and the second alignment film have a thickness of 200 nm or more. The light control unit according to claim 3, wherein both the first alignment film and the second alignment film have a thickness of 200 nm or more. The first laminated body has a first hard coat layer between the first resin base material and the first electrode layer, and a first low refractive index having a refractive index smaller than that of the first hard coat layer. The light control unit according to any one of claims 1 to 4, which has a rate layer in order. The first laminate has a first hard coat layer between the first resin base material and the first electrode layer, and a first high refractive index having a refractive index higher than that of the first hard coat layer. 5. The light control unit according to claim 1, further comprising a refractive index layer and a first low refractive index layer having a refractive index lower than that of the first high refractive index layer in order. A second low refractive index in which the second laminate has a refractive index smaller than that of the second hard coat layer and the second hard coat layer between the second resin base material and the second electrode layer. The light control unit according to any one of claims 1 to 6, which has a rate layer in order. The second laminated body has a second hard coat layer between the second resin base material and the second electrode layer, and a second high refractive index having a refractive index larger than that of the second hard coat layer. The light control unit according to claim 1, further comprising a refractive index layer and a second low refractive index layer having a refractive index lower than that of the second high refractive index layer in order. Before performing a weather resistance test on the light control unit, L ^* a ^* b was measured with a voltage applied to the liquid crystal layer so that the light transmittance of the liquid crystal layer was minimum or maximum. ^* L ^* , a ^*, and b ^* of the color system are defined as L ₁ ^* , a ₁ ^*, and b ₁ ^* , respectively, and after performing a weather resistance test on the light control unit under the following conditions, the liquid crystal layer The L ^* a ^* b ^* color system L ^* , a ^*, and b ^* measured with a voltage applied to the liquid crystal layer such that the light transmittance is minimum or maximum are L ₂ ^* , a, respectively. ₂ ^* and _b ^{2 *} and the time, at _{^{ΔE = ((L 2 * -L}} 1 *) 2 + (a 2 * -a 1 *) 2 + (b 2 * -b 1 *) 2) 1/2 The light control sheet according to claim 1, wherein the defined color difference ΔE is 3.0 or less.
[Conditions for weather resistance test]
・Weather resistance tester: Atlas Weatherometer CI4000
・Test time: 250 hours ・Light source: Xenon arc lamp ・Black panel temperature: 63±3℃
・Relative humidity: 50±5% (during irradiation)
・Sample surface irradiance: 60 W/m ² (continuous irradiation at 300 to 400 nm)
・Inner filter: Type S borosilicate ・Outer filter: Type S borosilicate The light control unit according to any one of claims 1 to 9, wherein the light control unit includes a spacer provided between the first stacked body and the second stacked body. A light control unit according to any one of claims 1 to 10,
A light transmissive member laminated on the light control unit,
A light control member.