JP2023130568A - Light control sheet, photosensitive composition and manufacturing method of light control sheet - Google Patents

Abstract

To provide a light control sheet capable of suppressing peeling between a light control layer and a transparent electrode layer, while suppressing cohesion of spacers; photosensitive compositions and a manufacturing method of the light control sheet.SOLUTION: A light control sheet 10 comprises a light control layer 11 including an organic polymer layer 11A, liquid crystal compositions 11B and spacers SP, transparent electrode layers 12A and 12B, and transparent support layers 13A and 13B. The organic polymer layer 11A is a polymer obtained by polymerizing a photopolymerizable compound; and the photopolymerizable compound is at least one type selected from a monomer containing one or both of an acryloyl group and a methacryloyl group and containing at least one type selected from a group consisting of a hydrocarbon group, an ether group, an ester group and an amide group, and a monomer containing any one of an acryloyl group and the methacryloyl group and containing a hydroxy group, where a glass-transition temperature of the polymer is 323 K or more and 363 K or less.SELECTED DRAWING: Figure 2

Description

The present invention relates to a light control sheet, a photosensitive composition, and a method for producing a light control sheet.

The light control sheet includes a light control layer and a pair of transparent electrode layers sandwiching the light control layer. The light control layer includes, for example, a transparent organic polymer layer, a liquid crystal composition, and a spacer for controlling the thickness of the light control layer. The organic polymer layer has multiple voids. The liquid crystal composition fills the voids in the organic polymer layer. The liquid crystal composition includes liquid crystal molecules. The liquid crystal molecules have different orientations between a state in which no potential difference occurs between the pair of transparent electrode layers and a state in which a potential difference occurs between the pair of transparent electrode layers. For example, a light control sheet exhibits an opaque state due to the alignment of liquid crystal molecules when there is no potential difference between a pair of transparent electrode layers, and an opaque state due to the alignment of liquid crystal molecules when a potential difference is generated between a pair of transparent electrode layers. Indicates a transparent state.

A light control sheet requires high adhesion between each layer from the viewpoint of suppressing peeling of each layer constituting the light control sheet during manufacturing and processing. For example, by forming an organic polymer layer by polymerizing a photosensitive composition containing a highly polar monomer such as a polymerizable phosphoric acid compound, the polarity of the organic polymer layer can be increased. Thereby, the adhesion between the light control layer and the transparent electrode layer can be improved (see, for example, Patent Document 1).

JP2018-203945A

However, when a monomer having relatively high polarity is used as a material for the organic polymer layer, spacers tend to aggregate depending on the polarity of the monomer in the photosensitive composition containing the raw materials for the light control layer. When the spacers aggregate in the photosensitive composition, the thickness of the light control layer tends to vary due to uneven distribution of the spacers. Further, excessive aggregation of spacers may prevent proper arrangement of the organic polymer layer and the liquid crystal composition in the light control layer, which may cause partial functional deterioration of the light control sheet.

A light control sheet for solving the above problems includes a light control layer including an organic polymer layer that partitions a plurality of voids, a liquid crystal composition that fills the voids, and a spacer, and a pair of transparent sheets sandwiching the light control layer. A light control sheet comprising an electrode layer, a pair of transparent support layers sandwiching the light control layer and the pair of transparent electrode layers, the light control sheet changing the transmittance of visible light by driving the liquid crystal composition, The polymer layer is a polymer obtained by polymerizing a photopolymerizable compound, and the photopolymerizable compound contains one or both of an acryloyl group and a methacryloyl group, and a hydrocarbon group, an ether group, At least one type selected from a monomer containing at least one type selected from the group consisting of an ester group and an amide group, and a monomer containing only one of an acryloyl group and a methacryloyl group and a hydroxy group. and the glass transition temperature Tg _ave of the polymer calculated using the following formula (1) from the glass transition temperature Tg _k of each photopolymerizable compound and the mass ratio W _k of each photopolymerizable compound is 323K or more. It is 363K or less.

A photosensitive composition for solving the above problems is a photosensitive composition for producing a light control layer, and includes a photopolymerizable compound and a liquid crystal composition, the photopolymerizable compound comprising: A monomer containing one or both of an acryloyl group and a methacryloyl group, and at least one selected from the group consisting of a hydrocarbon group, an ether group, an ester group, and an amide group, and an acryloyl group and a methacryloyl group. and at least one monomer containing a hydroxy group, and the glass transition temperature Tg _ave of the polymer obtained by polymerizing the photopolymerizable compound, and each light The glass transition temperature Tg _ave calculated from the glass transition temperature Tg _k of the polymerizable compound and the mass ratio W _k of each photopolymerizable compound using the above formula (1) is 323K or more and 363K or less.

A method for producing a light control sheet for solving the above problems includes a photosensitive composition containing a photopolymerizable compound and a liquid crystal composition in the transparent electrode layer of a laminate including a transparent electrode layer and a transparent support layer. and applying light while the photosensitive composition is placed between the laminate coated with the photosensitive composition and the other laminate. a step of polymerizing a photopolymerizable compound to form a polymer, the photopolymerizable compound containing either or both of an acryloyl group and a methacryloyl group, and a hydrocarbon group, an ether group, or an ester group. , a monomer containing at least one selected from the group consisting of an amide group, and a monomer containing only one of an acryloyl group and a methacryloyl group, and a hydroxy group. , the glass transition temperature Tg _ave of the polymer calculated using the above formula (1) from the glass transition temperature Tg _k of each photopolymerizable compound and the mass ratio W _k of each photopolymerizable compound is 323K or more and 363K or less It is.

According to each of the above structures and the above manufacturing method, by using a monomer constituted by an atomic group with relatively low polarity as a photopolymerizable compound, it is possible to suppress aggregation of spacers when forming a light control layer. Further, by setting the glass transition temperature Tg _ave of the polymer constituting the organic polymer layer to 323K or higher, excessive softening of the light control layer is suppressed. Therefore, the mechanical strength of the light control layer can be increased. Thereby, peeling within the light control layer can be suppressed. By setting the glass transition temperature Tg _ave of the polymer constituting the organic polymer layer to 363K or less, excessive hardening of the light control layer is suppressed, thereby improving the adhesion between the light control layer and the transparent electrode layer. can be increased. Thereby, interlayer peeling between the light control layer and the transparent electrode layer can be suppressed.

In the light control sheet, at least one of the photopolymerizable compounds is a monomer represented by the following formula (2), R ¹ and R ² are each hydrogen or a methyl group, and the number of repeating units n is , 5 or more and 20 or less, and the mass ratio of the monomer represented by the following formula (2) is preferably 2.5% or more and 10% or less based on the total solid content of the light control layer.

In the above photosensitive composition, at least one of the photopolymerizable compounds is a monomer represented by the above formula (2), R ¹ and R ² are hydrogen or a methyl group, and the number of repeating units n is , 5 or more and 20 or less, and the mass ratio of the monomer represented by the above formula (2) is preferably 2.5% or more and 10% or less based on the total solid content of the photosensitive composition.

In the method for producing a light control sheet, at least one of the photopolymerizable compounds is a monomer represented by the above formula (2), R ¹ and R ² are hydrogen or a methyl group, and the number of repeating units is n is 5 or more and 20 or less, and the mass ratio of the monomer represented by the above formula (2) is preferably 2.5% or more and 10% or less based on the total solid content of the photosensitive composition. .

According to each of the above configurations and the above manufacturing method, the polarity of the organic polymer layer in the monomer state can be set to suppress the aggregation of the spacer, while the polarity of the organic polymer layer in the state of the organic polymer layer in which the monomers are polymerized is increased, so that the light control layer The adhesion between the transparent electrode layer and the transparent electrode layer can be further improved.

According to the present invention, peeling between the light control layer and the transparent electrode layer can be suppressed while suppressing aggregation of spacers.

FIG. 1 is a schematic diagram showing the layer structure of a light control sheet. FIG. 2 is a schematic diagram showing the structure of the light control layer. FIG. 3 is a table showing the component ratios and evaluation results of Examples 1 to 7. FIG. 4 is a table showing the component ratios and evaluation results of Examples 8 to 14. FIG. 5 is a table showing the component ratios and evaluation results of Examples 15 to 17 and Comparative Examples 1 to 4. FIG. 6 is a table showing the component ratios and evaluation results of Comparative Examples 5 to 11. FIG. 7 is a diagram showing the appearance of the light control sheet after the peel test.

[Dimmer sheet]
The light control sheet is attached to a transparent base material to which it is attached. The transparent base material is a glass substrate or a resin substrate. Examples of transparent substrates include window glasses mounted on moving objects such as vehicles and aircraft, window glasses installed in buildings, and partitions placed inside cars and indoors. The surface to which the light control sheet is attached is flat or curved. The light control sheet may be sandwiched between two transparent substrates.

The drive type of the light control sheet of this embodiment is, for example, a normal type in which the light control sheet changes from an opaque state to a transparent state by applying a voltage, and returns from the transparent state to an opaque state by canceling the voltage application. Note that the light control sheet may be of a reverse type, in which the light control sheet changes from a transparent state to an opaque state by applying a voltage, and returns from an opaque state to a transparent state by canceling the voltage application.

[Laminated structure of light control sheet]
As shown in FIG. 1, the light control sheet 10 includes a light control layer 11, a first transparent electrode layer 12A, a second transparent electrode layer 12B, a first transparent support layer 13A, and a second transparent support layer 13B. The light control layer 11 is sandwiched between a first transparent electrode layer 12A and a second transparent electrode layer 12B. The first transparent support layer 13A supports the surface of the first transparent electrode layer 12A opposite to the light control layer 11. The second transparent support layer 13B supports the surface of the second transparent electrode layer 12B opposite to the light control layer 11.

The light control layer 11 is made of, for example, polymer dispersed liquid crystal (PDLC), polymer network liquid crystal (PNLC), capsule type nematic liquid crystal (NCAP), etc. Has a structure. The light control layer 11 containing polymer-dispersed liquid crystal has a resin layer with a large number of independent voids or voids having a shape in which parts of independent shapes are joined, and a liquid crystal composition is filled in the voids. Hold. A polymer network type liquid crystal includes a polymer network, which is a resin layer having a three-dimensional mesh shape, and holds liquid crystal molecules as aligned particles in the voids of the polymer network. The capsule-type nematic liquid crystal layer holds a capsule-shaped liquid crystal composition in a resin layer. The light control layer 11 of this embodiment includes a polymer network type liquid crystal.

The first transparent electrode layer 12A and the second transparent electrode layer 12B each have optical transparency to transmit visible light and electrical conductivity. Examples of materials constituting the first transparent electrode layer 12A and the second transparent electrode layer 12B include indium tin oxide, fluorine-doped tin oxide, tin oxide, zinc oxide, carbon nanotubes, and poly 3,4-ethylenedioxythiophene, respectively. At least one type selected from the group consisting of:

The first transparent support layer 13A and the second transparent support layer 13B each have a light transmittance that transmits visible light and an electrical insulation property. The materials constituting the first transparent support layer 13A and the second transparent support layer 13B are each an organic polymer compound or an inorganic polymer compound. An example of the organic polymer compound is at least one selected from the group consisting of polyester, polyacrylate, polycarbonate, and polyolefin. An example of the inorganic polymer compound is at least one selected from the group consisting of silicon dioxide, silicon oxynitride, and silicon nitride.

The first transparent electrode layer 12A is connected to the control unit 20 through the first wiring 21A and the first electrode 22A. The second transparent electrode layer 12B is connected to the control unit 20 through a second wiring 21B and a second electrode 22B. Each of the first wiring 21A and the second wiring 21B is composed of, for example, a metal wire and an insulating layer covering the metal wire. The wire is made of copper, for example. The insulating layer is made of resin, for example. Each of the first electrode 22A and the second electrode 22B is, for example, a flexible printed circuit (FPC).

Each of the first electrode 22A and the second electrode 22B is attached to each of the first transparent electrode layer 12A and the second transparent electrode layer 12B, for example, via a conductive adhesive layer (not shown). The conductive adhesive layer is, for example, an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), an isotropic conductive film (ICF), an isotropic conductive film, or an isotropic conductive film. It is composed of conductive paste (ICP: Isotropic Conductive Paste) or the like.

Note that the connection means between the first transparent electrode layer 12A and the control section 20 and the connection means between the second transparent electrode layer 12B and the control section 20 are not limited to the above example. For example, the first wiring 21A may be directly soldered to the first transparent electrode layer 12A without using the first electrode 22A. Similarly, the second wiring 21B may be directly soldered to the second transparent electrode layer 12B without using the first electrode 22A.

The control unit 20 applies a voltage between the first transparent electrode layer 12A and the second transparent electrode layer 12B. The light control layer 11 changes the orientation of liquid crystal molecules in response to a change in voltage generated between the first transparent electrode layer 12A and the second transparent electrode layer 12B. Changes in orientation in the liquid crystal molecules change the degree of scattering, absorption, and transmission of visible light entering the light control layer 11. In the light control layer 11, when no voltage signal is applied to the first transparent electrode layer 12A and the second transparent electrode layer 12B, the direction of the long axis of the liquid crystal molecules is irregular. The degree of scattering of visible light increases, resulting in an opaque state. On the other hand, in the light control layer 11, when a voltage signal is applied to the first transparent electrode layer 12A and the second transparent electrode layer 12B, the liquid crystal molecules are oriented so that the long axis direction of the liquid crystal molecules is aligned with the first transparent electrode layer 12B. The direction is along the direction of the electric field between the layer 12A and the second transparent electrode layer 12B. As a result, the light control layer 11 becomes transparent through which visible light can easily pass through.

[Dimmer layer]
The light control layer 11 will be described in detail with reference to FIG. 2. FIG. 2 shows a part of the cross-sectional structure of the PNLC type light control sheet 10. The light control layer 11 includes an organic polymer layer 11A, a liquid crystal composition 11B, and a spacer SP. The organic polymer layer 11A defines voids 11D within the light control layer 11. The liquid crystal composition 11B fills the void 11D.

The light control layer 11 is a cured product of a photosensitive composition for manufacturing the light control layer 11. The photosensitive composition includes, for example, a photopolymerizable compound, a liquid crystal composition 11B, a polymerization initiator, and a spacer SP. The organic polymer layer 11A is a cured product of a photopolymerizable compound. The photopolymerizable compound is compatible with liquid crystal composition 11B. As the photopolymerizable compound, a monomer composed of atomic groups with relatively low polarity is used. The photopolymerizable compound is one type of monomer or a combination of two or more types of monomers that satisfy either Condition 1 or Condition 2 below.

- (Condition 1) Contains either or both of an acryloyl group and a methacryloyl group, and at least one selected from the group consisting of a hydrocarbon group, an ether group, an ester group, and an amide group.

- (Condition 2) Contains only one of either an acryloyl group or a methacryloyl group, and also a hydroxy group.
A monomer that satisfies the above condition 1 or 2 is constituted by an atomic group with relatively low polarity, and therefore is difficult to induce aggregation of the spacer SP. Therefore, by using a monomer that satisfies the above conditions 1 or 2 as a photopolymerizable compound, when forming the light control layer 11, it is possible to suppress aggregation of the spacers SP that occurs in the photosensitive composition.

The organic polymer layer 11A is composed of a polymer obtained by polymerizing the above monomers. The glass transition temperature Tg _ave of the polymer constituting the organic polymer layer 11A is 323K or more and 363K or less. The glass transition temperature Tg _ave of the polymer can be calculated from the glass transition temperature Tg _k of each monomer and the mass ratio W _k of each monomer in the light control layer 11 using the following formula (1).

Glass transition temperature is an index of viscoelasticity in resin materials. For example, the higher the glass transition temperature, the more likely the resin material will harden and become glassy at room temperature, and the lower the glass transition temperature, the easier the resin material will be softened and become rubbery at room temperature. Excessive softening of the light control layer 11 is suppressed because the glass transition temperature Tg _ave of the polymer constituting the organic polymer layer 11A is 323K or higher. Therefore, the mechanical strength of the light control layer 11 can be increased. Thereby, in the light control sheet 10, peeling within the light control layer 11 can be suppressed. By setting the glass transition temperature Tg _ave of the polymer constituting the organic polymer layer 11A to 363K or less, excessive hardening of the light control layer 11 is suppressed, so that the light control layer 11 and the transparent electrode layer 12A, 12B can be improved. Thereby, in the light control sheet 10, interlayer peeling between the light control layer 11 and the transparent electrode layers 12A and 12B can be suppressed.

Further, at least one kind of the photopolymerizable compound is preferably a monomer that satisfies the following condition 3 among the monomers that satisfy either of the above conditions 1 and 2.
- (Condition 3) A monomer represented by the following formula (2).

In the above formula (2), R ¹ and R ² are each hydrogen or a methyl group. The number n of repeating units is 5 or more and 20 or less. The mass ratio of the monomer represented by the above formula (2) is, for example, 2.5% or more and 10% or less based on the total solid content of the photosensitive composition. Note that the mass ratio of the monomer represented by the above formula (2) is, for example, 2.5% or more and 10% or less with respect to the total solid content of the light control layer 11.

By using the monomer represented by the above formula (2), the polarity of the monomer state is set to a level that does not induce aggregation of the spacer SP, and the polarity of the state of the organic polymer layer 11A in which the monomer is polymerized is increased to make it transparent. Adhesion with the electrode layers 12A and 12B can be improved.

Liquid crystal composition 11B includes liquid crystal compound 11BL. Note that the liquid crystal composition 11B may further contain a viscosity reducing agent, an antifoaming agent, an antioxidant, a weathering agent, a dichroic dye, and the like. Examples of weathering agents are ultraviolet absorbers and light stabilizers.

The type of retention of the liquid crystal composition 11B by the organic polymer layer 11A is one selected from the group consisting of a polymer dispersion type, a polymer network type, and a capsule type. Alternatively, the type of retention of the liquid crystal composition 11B by the organic polymer layer 11A may be a type combining a plurality of types from these groups.

The organic polymer layer 11A of the polymer-dispersed light control layer 11 defines a large number of isolated voids 11D. The organic polymer layer 11A of the polymer network type light control layer 11 has three-dimensional mesh-like voids 11D. The liquid crystal composition 11B is located within the interconnected mesh-like voids 11D. The organic polymer layer 11A of the capsule-shaped light control layer 11 has dispersed capsule-shaped voids 11D. The size of the void 11D is two or more types, and the shape of the void 11D is spherical, ellipsoidal, or irregular.

The dielectric constant of the liquid crystal compound 11BL in the long axis direction is higher than the dielectric constant of the liquid crystal compound 11BL in the short axis direction, and has positive dielectric anisotropy. Alternatively, the dielectric constant of the liquid crystal compound 11BL in the long axis direction is lower than the dielectric constant of the liquid crystal compound 11BL in the short axis direction, and has negative dielectric anisotropy. The dielectric anisotropy of the liquid crystal compound 11BL is appropriately selected based on the presence or absence of each alignment layer in the light control sheet 10 and the driving type.

The liquid crystal compound 11BL is a Schiff base type, an azo type, an azoxy type, a biphenyl type, a terphenyl type, a benzoic acid ester type, a tolan type, a pyrimidine type, a pyridazine type, a cyclohexanecarboxylic acid ester type, a phenylcyclohexane type, a biphenylcyclohexane type, At least one type selected from the group consisting of dicyanobenzene, naphthalene, and dioxane. The non-polymerizable liquid crystal compound is one type of liquid crystal compound or a combination of two or more types of liquid crystal compounds.

The lower limit of the content of the organic polymer layer 11A with respect to the total amount of the organic polymer layer 11A and the liquid crystal composition 11B is 20% by mass, and the more preferable lower limit of the content is 30% by mass. The upper limit of the content of the organic polymer layer 11A with respect to the total amount of the organic polymer layer 11A and the liquid crystal composition 11B is 70% by mass, and the more preferable upper limit of the content is 60% by mass.

The lower limit and upper limit of the content of the organic polymer layer 11A are determined according to the range in which the liquid crystal particles made of the liquid crystal composition 11B can be phase-separated from the cured product of the photopolymerizable compound during the curing process of the photopolymerizable compound. It's decided. When it is necessary to increase the mechanical strength of the organic polymer layer 11A, it is preferable that the lower limit of the content of the organic polymer layer 11A is high. When it is necessary to lower the driving voltage of the liquid crystal compound 11BL, it is preferable that the upper limit of the content of the organic polymer layer 11A is low.

The spacers SP are dispersed throughout the organic polymer layer 11A. The spacer SP determines the thickness of the light control layer 11 around the spacer SP, and also makes the thickness of the light control layer 11 uniform. The spacer SP is, for example, a granular spacer. The spacer SP has translucency and may be colorless and transparent or colored and transparent.

The polymerization initiator is at least one selected from the group consisting of diketone compounds, acetophenone compounds, benzoin compounds, benzophenone compounds, and thioxanthone compounds. The polymerization initiator may be one type of compound or a combination of two or more types of compounds. An example of the polymerization initiator is one selected from the group consisting of benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and cyclohexylphenyl ketone.

The control unit 20 applies a driving voltage to the first transparent electrode layer 12A and the second transparent electrode layer 12B, so that the liquid crystal compound 11BL is controlled by the potential difference between the first transparent electrode layer 12A and the second transparent electrode layer 12B. Control orientation. The driving voltage is a voltage for changing the transmittance of visible light in the light control layer 11 by driving the liquid crystal compound 11BL. The control unit 20 changes the alignment state of the liquid crystal compound 11BL and switches the state of the light control sheet 10 from one of the transparent state and the opaque state to the other. The light control sheet 10 in an opaque state has a higher haze, which is a cloudiness value, than in a transparent state.

When the application of the driving voltage is removed, the long axis direction of the liquid crystal compound 11BL becomes disordered. As a result, the light control sheet 10 causes scattering in the light control layer 11 over the entire visible light range, and becomes opaque. When a driving voltage is applied, the liquid crystal compound 11BL receives an alignment regulating force due to an electric field. At this time, the long axis direction of the liquid crystal compound 11BL is aligned along the electric field direction. Thereby, the total light transmittance of the light control sheet 10 becomes higher than that in the opaque state. When the application of the driving voltage is removed again, the alignment regulating force caused by the electric field is removed from the liquid crystal compound 11BL, and the long axis direction of the liquid crystal compound 11BL becomes disordered. As a result, the light control sheet 10 causes scattering in the light control layer 11 over the entire visible light range, and becomes opaque again.

[Manufacturing method of light control sheet]
The method for manufacturing the light control sheet 10 includes preparing a sheet consisting of a first transparent support layer 13A having a first transparent electrode layer 12A and a sheet consisting of a second transparent support layer 13B having a second transparent electrode layer 12B. do. The first transparent electrode layer 12A and the second transparent electrode layer 12B are formed by a known thin film forming method such as sputtering, vacuum deposition, or coating.

Next, a photosensitive composition is prepared. The photosensitive composition is prepared by mixing and stirring a photopolymerizable compound, which is a monomer that satisfies Condition 1 or Condition 2 above, liquid crystal composition 11B, a polymerization initiator, spacer SP, and other additives. can get.

Then, a step of applying a photosensitive composition to at least one of the pair of sheets is performed. The coating method is a known method such as an inkjet method, a gravure coating method, a spin coating method, a slit coating method, a bar coating method, a flexo coating method, a die coating method, a dip coating method, a roll coating method, and the like. Thereafter, the pair of sheets are bonded together with the layer coated with the photosensitive composition facing inside. Finally, a step is performed in which the stack of sheets sandwiching the layer coated with the photosensitive composition is irradiated with light of a specific wavelength, such as ultraviolet rays, that advances the polymerization reaction of the polymerizable composition. This forms the light control layer 11.

[Effects of embodiment]
According to this embodiment, the effects listed below can be obtained.
(1) By using a monomer that satisfies either Condition 1 or Condition 2 above as the photopolymerizable compound, the light control layer 11 can be Aggregation of spacers SP during formation can be suppressed.

(2) By setting the glass transition temperature Tg _ave of the polymer constituting the organic polymer layer 11A to 323K or higher, excessive softening of the light control layer 11 can be suppressed and the mechanical strength of the light control layer 11 can be increased. can. Thereby, in the light control sheet 10, peeling within the light control layer 11 can be suppressed.

(3) By setting the glass transition temperature Tg _ave of the polymer constituting the organic polymer layer 11A to 363K or less, excessive hardening of the light control layer 11 is suppressed, so that the light control layer 11 and the transparent electrode layer 12A , 12B can be improved. Thereby, in the light control sheet 10, interlayer peeling between the light control layer 11 and the transparent electrode layers 12A and 12B can be suppressed.

(4) By using a monomer that satisfies the above condition 3 as the photopolymerizable compound, while suppressing the aggregation of the spacer SP in the monomer state, the light control layer 11 and the transparent electrode layer in the state of the organic polymer layer 11A The adhesion between 12A and 12B can be further improved.

[Example]
Examples and comparative examples will be described with reference to FIGS. 3 to 7. Note that the following examples are examples for explaining the effects of the above embodiments, and do not limit the present invention. Moreover, in Examples and Comparative Examples, a plurality of monomers among the first to fourteenth monomers described below were used as photopolymerizable compounds.

[First monomer]
・Monomer name: Isobornyl acrylate (manufactured by Shin Nakamura Chemical Co., Ltd.)
・Functional group: Hydrocarbon group only ・Glass transition temperature: 370.15K
・Suitable conditions: Condition 1
・Molecular skeleton: Formula (3)

[Second monomer]
・Monomer name: 2-ethylhexyl acrylate (manufactured by Mitsubishi Chemical Corporation)
・Functional group: Hydrocarbon group only ・Glass transition temperature: 203.15K
・Suitable conditions: Condition 1
・Molecular skeleton: Formula (4)

[Third monomer]
・Monomer name: Trimethylolpropane triacrylate (manufactured by Shin Nakamura Chemical Co., Ltd.)
・Functional group: Hydrocarbon group only ・Glass transition temperature: 335.15K
・Suitable conditions: Condition 1
・Molecular skeleton: Formula (5)

[Fourth monomer]
・Monomer name: Light acrylate MTG-A (manufactured by Kyoeisha Chemical Co., Ltd., Light acrylate is a registered trademark)
・Functional group: Ether group ・Glass transition temperature: 223.15K
・Suitable conditions: Condition 1
・Molecular skeleton: Formula (6)

[Fifth monomer]
・Monomer name: Light acrylate 3EG-A (manufactured by Kyoeisha Chemical Co., Ltd., Light acrylate is a registered trademark)
・Functional group: Ether group ・Glass transition temperature: 323.15K
・Suitable conditions: Condition 1
・Molecular skeleton: Formula (7)

[Sixth monomer]
・Monomer name: Light acrylate 9EG-A (manufactured by Kyoeisha Chemical Co., Ltd., Light acrylate is a registered trademark)
・Functional group: Ether group ・Glass transition temperature: 276.15K
・Suitable conditions: Condition 1, Condition 3
・Molecular skeleton: Formula (8)

[Seventh monomer]
・Monomer name: Light acrylate 14EG-A (manufactured by Kyoeisha Chemical Co., Ltd., Light acrylate is a registered trademark)
・Functional group: Ether group ・Glass transition temperature: 231.15K
・Suitable conditions: Condition 1, Condition 3
・Molecular skeleton: Formula (9)

[Eighth monomer]
・Monomer name: N,N-diethylacrylamide (manufactured by Tokyo Chemical Industry Co., Ltd.)
・Functional group: Amide group ・Glass transition temperature: 354.15K
・Suitable conditions: Condition 1
・Molecular skeleton: Formula (10)

[9th monomer]
・Monomer name: 2-hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
・Functional group: Hydroxy group ・Glass transition temperature: 328.15K
・Suitable conditions: Condition 2
・Molecular skeleton: Formula (11)

[10th monomer]
・Monomer name: NK ester-701 (manufactured by Shin Nakamura Chemical Co., Ltd.)
・Functional group: Hydroxy group ・Glass transition temperature: 280.00K
・Compatible conditions: None ・Molecular skeleton: Formula (12)

[11th monomer]
・Monomer name: Epoxy ester 70PA (manufactured by Kyoeisha Chemical Co., Ltd.)
・Functional group: Hydroxy group ・Glass transition temperature: 320.00K
・Compatible conditions: None ・Molecular skeleton: Formula (13)

[12th monomer]
・Monomer name: Epoxy ester 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.)
・Functional group: Hydroxy group ・Glass transition temperature: 360.00K
・Compatible conditions: None ・Molecular skeleton: Formula (14)

[13th monomer]
・Monomer name: Carboxyethyl acrylate (manufactured by Sigma-Aldrich Japan LLC)
・Functional group: Carboxy group ・Glass transition temperature: 370.00K
・Compatible conditions: None ・Molecular skeleton: Formula (15)

[14th monomer]
・Monomer name: Light Ester P-1M (manufactured by Kyoeisha Chemical Co., Ltd.)
・Functional group: Phosphoric acid group ・Glass transition temperature: 360.00K
・Compatible conditions: None ・Molecular skeleton: Formula (16)

[Example 1]
As shown in FIG. 3, first, a photosensitive composition for forming the light control layer 11 was prepared. The photosensitive composition contains 42.3% by mass of the first monomer, 4.7% by mass of the fourth monomer, and 50% by mass of the liquid crystal compound 11BL, based on the total solid content contained in the photosensitive composition. It was configured to contain 2% by mass of a polymerization initiator and 1% by mass of a spacer SP. As the liquid crystal compound 11BL, MLC-6609 (manufactured by Merck & Co., Ltd.) was used. As a polymerization initiator, 2-hydroxy-2-methyl-1-phenylpropanone (manufactured by IGM Resins) was used. Micropearl SP-214 (manufactured by Sekisui Chemical Co., Ltd., Micropearl is a registered trademark) was used as the spacer SP.

A first sheet containing a first transparent electrode layer 12A made of indium tin oxide (ITO) and a first transparent support layer 13A made of polyethylene terephthalate was prepared. Similarly, a second sheet including a second transparent electrode layer 12B made of indium tin oxide and a second transparent support layer 13B made of polyethylene terephthalate was prepared. A photosensitive composition for forming the light control layer 11 was applied to the surface of the first sheet where the first transparent electrode layer 12A was exposed. Then, the photosensitive composition was irradiated with ultraviolet rays with the photosensitive composition sandwiched between the pair of sheets so that the exposed surface of the second transparent electrode layer 12B of the second sheet was in contact with the photosensitive composition. . Thereby, the photopolymerizable compound was polymerized and the photosensitive composition was cured. Through the above procedure, the light control sheet 10 of Example 1 was obtained. The glass transition temperature Tg _ave of the polymer contained in the light control layer 11 of Example 1 was 347.3K.

[Example 2]
The light control sheet 10 of Example 2 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 40.0% by mass of the first monomer, 7.0% by mass of the fifth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 362.7K.

[Example 3]
The light control sheet 10 of Example 3 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 37.6% by mass of a first monomer, 9.4% by mass of a fifth monomer, 50% by mass of liquid crystal compound 11BL, 2% by mass of a polymerization initiator, and 1% by mass of a polymerization initiator. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 359.7K.

[Example 4]
The light control sheet 10 of Example 4 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 28.2% by mass of a first monomer, 18.8% by mass of a fifth monomer, 50% by mass of liquid crystal compound 11BL, 2% by mass of a polymerization initiator, and 1% by mass of a polymerization initiator. The spacer SP is configured to include a spacer SP. The glass transition temperature _Tgave of the polymer included in the light control layer 11 was 349.8K.

[Example 5]
The light control sheet 10 of Example 5 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 44.2% by mass of the first monomer, 2.8% by mass of the sixth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 362.7K.

[Example 6]
The light control sheet 10 of Example 6 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 51.3% by mass of the first monomer, 5.7% by mass of the sixth monomer, 40% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 358.0K.

[Example 7]
The light control sheet 10 of Example 7 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 42.3% by mass of the first monomer, 4.7% by mass of the sixth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 358.0K.

[Example 8]
As shown in FIG. 4, the light control sheet 10 of Example 8 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 33.3% by mass of the first monomer, 3.7% by mass of the sixth monomer, 60% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 358.0K.

[Example 9]
The light control sheet 10 of Example 9 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 37.6% by mass of the first monomer, 9.4% by mass of the sixth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 346.6K.

[Example 10]
The light control sheet 10 of Example 10 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 44.2% by mass of the first monomer, 2.8% by mass of the seventh monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 357.3K.

[Example 11]
The light control sheet 10 of Example 11 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 51.3% by mass of the first monomer, 5.7% by mass of the seventh monomer, 40% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 349.2K.

[Example 12]
The light control sheet 10 of Example 12 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 42.3% by mass of the first monomer, 4.7% by mass of the seventh monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 349.2K.

[Example 13]
The light control sheet 10 of Example 13 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 33.3% by mass of the first monomer, 3.7% by mass of the seventh monomer, 60% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 349.2K.

[Example 14]
The light control sheet 10 of Example 14 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 37.6% by mass of the first monomer, 9.4% by mass of the seventh monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 330.4K.

[Example 15]
As shown in FIG. 5, the light control sheet 10 of Example 15 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 23.5% by mass of the first monomer, 23.5% by mass of the eighth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature _Tgave of the polymer included in the light control layer 11 was 362.0K.

[Example 16]
The light control sheet 10 of Example 16 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 37.6% by mass of the first monomer, 9.4% by mass of the ninth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 360.9K.

[Example 17]
The light control sheet 10 of Example 17 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition includes 26.8% by mass of the first monomer, 2.8% by mass of the second monomer, 14.6% by mass of the third monomer, and 2.8% by mass of the fourth monomer. It was configured to contain 50% by mass of liquid crystal compound 11BL, 2% by mass of polymerization initiator, and 1% by mass of spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 330.1K.

[Comparative example 1]
A light control sheet 10 of Comparative Example 1 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition includes 25.4% by mass of the first monomer, 7.0% by mass of the second monomer, 6.1% by mass of the third monomer, and 8.5% by mass of the fourth monomer. It was configured to contain 50% by mass of liquid crystal compound 11BL, 2% by mass of polymerization initiator, and 1% by mass of spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 294.8K.

[Comparative example 2]
A light control sheet 10 of Comparative Example 2 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition includes 43.7% by mass of the first monomer, 0.3% by mass of the second monomer, 2.8% by mass of the third monomer, and 0.2% by mass of the fourth monomer. It was configured to contain 50% by mass of liquid crystal compound 11BL, 2% by mass of polymerization initiator, and 1% by mass of spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 365.2K.

[Comparative example 3]
Light control sheet 10 of Comparative Example 3 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 45.8% by mass of the first monomer, 1.2% by mass of the sixth monomer, 50% by mass of liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer contained in the light control layer 11 was 367.0K.

[Comparative example 4]
Light control sheet 10 of Comparative Example 4 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 25.9% by mass of the first monomer, 21.1% by mass of the sixth monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 321.4K.

[Comparative example 5]
As shown in FIG. 6, a light control sheet 10 of Comparative Example 5 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 45.8% by mass of the first monomer, 1.2% by mass of the seventh monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 364.7K.

[Comparative example 6]
As shown in FIG. 6, a light control sheet 10 of Comparative Example 6 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 25.9% by mass of the first monomer, 21.1% by mass of the seventh monomer, 50% by mass of liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 291.7K.

[Comparative Example 7]
Light control sheet 10 of Comparative Example 7 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 42.3% by mass of the first monomer, 4.7% by mass of the 10th monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature _Tgave of the polymer included in the light control layer 11 was 358.6K.

[Comparative example 8]
Light control sheet 10 of Comparative Example 8 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 44.7% by mass of the first monomer, 2.3% by mass of the 11th monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 367.7K.

[Comparative Example 9]
Light control sheet 10 of Comparative Example 9 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 44.7% by mass of the first monomer, 2.3% by mass of the 12th monomer, 50% by mass of the liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 370.0K.

[Comparative Example 10]
A light control sheet 10 of Comparative Example 10 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 44.7% by mass of the first monomer, 2.3% by mass of the 13th monomer, 50% by mass of liquid crystal compound 11BL, 2% by mass of the polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 370.5K.

[Comparative Example 11]
A light control sheet 10 of Comparative Example 11 was obtained in the same manner as Example 1 except that the components of the photosensitive composition were different. The photosensitive composition contains 44.7% by mass of the first monomer, 2.3% by mass of the 14th monomer, 50% by mass of liquid crystal compound 11BL, 2% by mass of a polymerization initiator, and 1% by mass. The spacer SP is configured to include a spacer SP. The glass transition temperature Tg _ave of the polymer included in the light control layer 11 was 370.0K.

[Evaluation 1: Spacer dispersibility]
Regarding the photosensitive compositions used in each Example and each Comparative Example, the dispersibility of spacers SP was evaluated based on the presence or absence of sedimentation of spacers SP. A photosensitive composition in which the spacer SP is stably dispersed and no precipitation of the spacer SP is observed is marked as "○", and a photosensitive composition in which precipitation of the spacer SP is confirmed is marked as "x". did.

As shown in FIGS. 3 to 6, when the monomer used as the photopolymerizable compound satisfies either Condition 1 or Condition 2, as in Examples 1 to 17 and Comparative Examples 1 to 6, No sedimentation of spacer SP was confirmed. On the other hand, when a monomer containing two methacryloyl groups or two acryloyl groups in addition to a hydroxyl group was used as in Comparative Examples 7 to 9, precipitation of the spacer SP was confirmed in the photosensitive composition. It was done. When a monomer containing a carboxy group or a phosphoric acid group was used as in Comparative Examples 10 and 11, precipitation of the spacer SP was confirmed in the photosensitive composition. That is, when the monomer used as the photopolymerizable compound did not meet either Condition 1 or Condition 2, sedimentation of the spacer SP was confirmed in the photosensitive composition. Therefore, it was confirmed that sedimentation of the spacer SP can be suppressed by using a monomer with relatively low polarity as the photopolymerizable compound.

[Evaluation 2: Peeling test]
After cutting the light control sheet 10 of each example and each comparative example into a width of 25 mm, the first sheet of the pair of sheets sandwiching the light control layer 11 was peeled off at an angle of 180°, and the peel strength was measured. . As for the evaluation criteria, those with a peel strength of 0.1 N/25 mm or more were considered acceptable, and those with a peel strength of less than 0.1 N/25 mm were judged as failed.

Furthermore, the viscoelasticity of the light control layer 11 after the peel test was visually evaluated. The light control layer 11 has moderate viscoelasticity, and the light control layer 11 is glass-like and brittle, or the light control layer 11 is rubber-like and softened. I marked it with an “×”. The peel test was conducted on the light control sheets 10 of Examples 1 to 17 and Comparative Examples 1 to 6 in which no sedimentation of the spacer SP was observed in Evaluation 1.

As in Examples 1 to 17, when the glass transition temperature Tg _ave of the polymer polymerized with the photopolymerizable compound was 323 K or more and 363 K or less, the peel strength was 0.1 N/25 mm or more. In particular, Examples 5 to 14 that satisfied Condition 3 exhibited high peel strengths of 0.5 to 2.3 N/25 mm. On the other hand, when the glass transition temperature Tg _ave is less than 323K as in Comparative Examples 1, 4, and 6, or when the glass transition temperature Tg _ave is over 363K as in Comparative Examples 2, 3, and 5, The peel strength was less than 0.1 N/25 mm in all cases.

As shown in (a) in the table of FIG. 7, the light control layer 11 included in the light control sheets 10 of Examples 1 to 17 has a moderate viscoelasticity ( Evaluation result: 〇). The failure mode in the peel tests of Examples 1 to 17 was peeling at the interface between the light control layer 11 and the first transparent electrode layer 12A. No major damage was observed in the appearance of the light control layer 11 after the peel test in Examples 1 to 17.

As shown in (b) in the table of FIG. 7, the light control layer 11 included in the light control sheets 10 of Comparative Examples 1, 4, and 6 having a glass transition temperature Tg _ave of less than 323K was excessively softened and became rubbery. (Evaluation result: ×). The failure mode in the peel test of Comparative Examples 1, 4, and 6 was that in addition to peeling at the interface between the light control layer 11 and the first transparent electrode layer 12A, intralayer peeling occurred in a part of the light control layer 11. A failure mode in which the first transparent electrode layer 12A was adhered to and stretched was confirmed.

As shown in (c) in the table of FIG. 7, the light control layer 11 included in the light control sheets 10 of Comparative Examples 2, 3, and 5 having a glass transition temperature Tg _ave of over 363K was excessively hardened and brittle. It was glass-like (evaluation result: ×). The failure mode in the peel tests of Comparative Examples 2, 3, and 5 was peeling at the interface between the light control layer 11 and the first transparent electrode layer 12A, and as a result, peeling did not occur smoothly and peeled off intermittently. Zipping occurred. In the light control layer 11 after the peel test of Comparative Examples 2, 3, and 5, peel marks Z due to zipping were confirmed.

From the above, by setting the glass transition temperature Tg _ave of the polymer polymerized with the photopolymerizable compound to 323K or more and 363K or less, peeling within the light control layer 11 and the light control layer 11 and the first transparent electrode layer can be prevented. It was confirmed that interlayer peeling with 12A could be suppressed.

[Evaluation 3: Optical properties]
In the light control sheet 10 of each Example and each Comparative Example, haze was measured in each of the opaque state and transparent state. The measurement method was based on JIS K 7136:2000. Note that the haze in the transparent state was defined as the value when the haze value was saturated when a voltage was applied between the pair of transparent electrode layers.

As shown in FIGS. 3 to 6, the light control sheets 10 of Examples 1 to 17 and Comparative Examples 1 to 6 each have a haze of 20% or less in an opaque state and a haze of 80% or more in a transparent state. there were. For the light control sheets 10 of Comparative Examples 7 to 11 in which sedimentation of the spacer SP was confirmed, haze measurement was not performed.

[Example of change]
Note that the above embodiment can be modified and implemented as follows.
- The photopolymerizable compound may be one that satisfies at least either Condition 1 or Condition 2 above, and does not need to satisfy Condition 3.

- The spacer SP may not be added to the photosensitive composition, but may be included in the light control layer 11 by other means. For example, the spacers SP may be dispersed by applying a dispersion medium in which the spacers SP are dispersed to a sheet including a transparent electrode layer and a transparent support layer, and then heating the sheet to remove the solvent. Thereafter, by applying a photosensitive composition that does not contain the spacer SP, the light control layer 11 that contains the spacer SP is formed.

SP... Spacer 10... Light control sheet 11... Light control layer 11A... Organic polymer layer 11B... Liquid crystal composition 11BL... Liquid crystal compound 11D... Gap 12A... First transparent electrode layer 12B... Second transparent electrode layer 13A... First transparent Support layer 13B...Second transparent support layer 20...Driver 21A...First wiring 21B...Second wiring 22A...First electrode 22B...Second electrode

Claims (6)

an organic polymer layer that partitions a plurality of voids, a liquid crystal composition that fills the voids, and a light control layer that includes a spacer;
a pair of transparent electrode layers sandwiching the light control layer;
A pair of transparent support layers sandwiching the light control layer and the pair of transparent electrode layers,
A light control sheet that changes visible light transmittance by driving the liquid crystal composition,
The organic polymer layer is a polymer obtained by polymerizing a photopolymerizable compound,
The photopolymerizable compound is
A monomer containing one or both of an acryloyl group and a methacryloyl group, and at least one selected from the group consisting of a hydrocarbon group, an ether group, an ester group, and an amide group;
At least one kind selected from a monomer containing only one of an acryloyl group and a methacryloyl group and containing a hydroxy group,
The glass transition temperature Tg _ave of the polymer, which is calculated using the following formula (1) from the glass transition temperature Tg _k of each photopolymerizable compound and the mass ratio W _k of each photopolymerizable compound, is 323K or more and 363K or less. be

A light control sheet characterized by: At least one kind of the photopolymerizable compound is a monomer represented by the following formula (2),

R ¹ and R ² are each hydrogen or methyl group,
The number of repeating units n is 5 or more and 20 or less,
The light control sheet according to claim 1, wherein a mass ratio of the monomer represented by the above formula (2) is 2.5% or more and 10% or less based on the total solid content of the light control layer. . A photosensitive composition for producing a light control layer, comprising:
Including a photopolymerizable compound and a liquid crystal composition,
The photopolymerizable compound is
A monomer containing one or both of an acryloyl group and a methacryloyl group, and at least one selected from the group consisting of a hydrocarbon group, an ether group, an ester group, and an amide group;
At least one kind selected from a monomer containing only one of an acryloyl group and a methacryloyl group and containing a hydroxy group,
The glass transition temperature Tg _ave of the polymer obtained by polymerizing _the photopolymerizable compounds is expressed by the following _formula ( The glass transition temperature Tg _ave calculated using 1) is 323K or more and 363K or less.

A photosensitive composition characterized by: At least one kind of the photopolymerizable compound is a monomer represented by the following formula (2),

R ¹ and R ² are hydrogen or a methyl group,
The number of repeating units n is 5 or more and 20 or less,
The photosensitive composition according to claim 3, wherein the mass ratio of the monomer represented by the above formula (2) is 2.5% or more and 10% or less based on the total solid content of the photosensitive composition. Composition. Applying a photosensitive composition containing a photopolymerizable compound and a liquid crystal composition to the transparent electrode layer of the laminate including the transparent electrode layer and the transparent support layer;
The photopolymerizable compound is polymerized by irradiating light while the photosensitive composition is placed between the laminate coated with the photosensitive composition and the other laminate. forming a polymer;
The photopolymerizable compound is
A monomer containing one or both of an acryloyl group and a methacryloyl group, and at least one selected from the group consisting of a hydrocarbon group, an ether group, an ester group, and an amide group;
At least one kind selected from a monomer containing only one of an acryloyl group and a methacryloyl group and containing a hydroxy group,
The glass transition temperature Tg _ave of the polymer, which is calculated using the following formula (1) from the glass transition temperature Tg _k of each photopolymerizable compound and the mass ratio W _k of each photopolymerizable compound, is 323K or more and 363K or less. be

A method for manufacturing a light control sheet, characterized by the following. At least one kind of the photopolymerizable compound is a monomer represented by the following formula (2),

R ¹ and R ² are hydrogen or a methyl group,
The number of repeating units n is 5 or more and 20 or less,
The light control according to claim 5, wherein a mass ratio of the monomer represented by the above formula (2) is 2.5% or more and 10% or less based on the total solid content of the photosensitive composition. Method of manufacturing sheets.

Images