Dimming sheet, dimming device, and method for manufacturing dimming sheet

Abstract

The dimming layer (31) is provided with an ionizing-ray-curable resin layer (31P) that partitions a gap (31D), and a liquid crystal composition (31LC) that fills the gap (31D). A trifunctional or higher acrylic compound having a double bond equivalent of 150 g / eq or less is a first acrylic compound. And the monofunctional alkyl acrylate containing saturated alkyl is a second acrylic compound. And an acrylic compound having one or more and three or less functional groups and a polyoxyethylene chain and having a double bond equivalent weight of 300 g / eq or more and 700 g / eq or less is a third acrylic compound. The content of the first acrylic compound is from 5% by mass to 40% by mass (inclusive). The content of the second acrylic compound is from 55% by mass to 80% by mass (inclusive). The content of the third acrylic compound is from 5% by mass to 20% by mass (inclusive). Therefore, the dimming sheet can be driven in a low-temperature environment.

Description

Technical Field

[0001] The present disclosure relates to a dimming sheet in which gaps defined by an ionizing radiation curing resin layer are filled with a liquid crystal composition, a dimming device including the dimming sheet, and a method for manufacturing the dimming sheet. Background Art

[0002] The dimming film has a dimming layer between transparent electrode films. The dimming layer has an ionizing radiation curing resin layer that divides a plurality of gaps and a liquid crystal composition filled in the gaps. The voltage change between the transparent electrode films changes the orientation state of the liquid crystal compound contained in the liquid crystal composition. The change in the orientation state of the liquid crystal compound changes the scattering degree of the interface between the ionizing radiation curing resin layer and the liquid crystal composition, thereby changing the transparency of the dimming film.

[0003] The dimming film installation technology requires the dimming film to be heat-resistant. The intermediate film installation technology is to heat the glass substrate while holding the dimming film with the glass substrate for bonding. The transparent electrode film in the high temperature environment during bonding will produce low-molecular impurities from the transparent electrode film. Since the low-molecular impurities diffused into the dimming layer will deteriorate the electrical properties of the liquid crystal compound, the surface treatment layer of the transparent electrode film has a barrier function to inhibit the contact between the low-molecular impurities and the liquid crystal compound (for example, refer to Patent Document 1).

[0004] The time until the transparency of the dimming film responds to the voltage change between the transparent electrode films depends on the ambient temperature in which the dimming film is installed. The lower the ambient temperature in which the transparency of the dimming film can respond to the voltage change, the more suitable the dimming film is for use in a low-temperature environment. A configuration example for reducing the application temperature of the dimming film is to add a viscosity reducing agent to the liquid crystal composition in a manner that reduces the viscosity of the liquid crystal composition in a low-temperature environment (for example, see Patent Documents 2 and 3).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 6447757

[0008] Patent Document 2: Japanese Patent Application Publication No. 2022-148343

[0009] Patent Document 3: Japanese Patent Application Publication No. 2022-098845 Summary of the invention

[0010] Technical problem to be solved by the invention

[0011] Broadening the temperature range limited for driving the dimming layer can expand the application range of the dimming film and develop the related industries of the dimming film. The temperature limited for driving the dimming layer can be (i) the installation temperature of the dimming film or (ii) the ambient temperature of the dimming film.

[0012] (i) The mounting temperature of the dimming chip is restricted as follows.

[0013] The use of a flexible resin substrate or glass substrate in the substrate of the transparent electrode film makes it possible to produce the dimming film using roll-to-roll. On the other hand, the use of a substrate that is easily deformed in a high temperature environment limits the formation conditions of the dimming film to a low temperature environment in a manner that avoids a high temperature environment. When the orientation of the liquid crystal compound is required during the period when the supply of the voltage signal is stopped, as in the reverse dimming film, the dimming film has an orientation layer. The orientation layer that exerts an orientation restriction force on the liquid crystal compound is configured in a manner that contacts the dimming layer, regardless of the presence or absence of the above-mentioned surface treatment layer. The formation conditions are limited to the orientation layer in a low temperature environment containing unreacted substances such as polyamic acid or low molecular impurities such as residual solvents. Therefore, in the dimming film installation technology that requires heating, byproducts or residual solvents generated by unreacted substances will diffuse from the orientation layer configured in a manner that contacts the dimming layer to the dimming layer. As a result, the installation temperature of the dimming film is limited.

[0014] (ii) The ambient temperature of the dimming chip is limited as follows.

[0015] The addition of a viscosity reducer reduces the content of the ionizing radiation curing resin layer or the content of the liquid crystal compound in the light-adjusting layer. The reduction in the interface between the ionizing radiation curing resin layer and the liquid crystal composition caused by the reduction in the content reduces the degree of scattering of the light-adjusting sheet, so the viscosity reduction caused by the addition of a viscosity reducer is also limited. As a result, the ambient temperature of the light-adjusting sheet is limited.

[0016] Means for solving technical problems

[0017] The dimming sheet for solving the above technical problems comprises a first transparent electrode layer, a second transparent electrode layer, and a dimming layer located between the first transparent electrode layer and the second transparent electrode layer, and the haze of the dimming layer is changed by changing the voltage applied between the first transparent electrode layer and the second transparent electrode layer. The dimming layer comprises an ionizing radiation curing resin layer dividing a gap and a liquid crystal composition filled in the gap, acryloyl and methacryloyl are functional groups, and among the acrylic compounds constituting the ionizing radiation curing resin layer, an acrylic compound having three or more of the above functional groups and a double bond equivalent of 150 g / eq or less is the first acrylic compound, and the content of the first acrylic compound constituting the ionizing radiation curing resin layer is 2% by mass or more of the above ionizing radiation curing resin layer.

[0018] A dimming device for solving the above technical problems is a dimming device having a dimming sheet and a driving unit for applying a voltage to the dimming sheet. The dimming sheet has a first transparent electrode layer, a second transparent electrode layer, and a dimming layer located between the first transparent electrode layer and the second transparent electrode layer, and the haze of the dimming layer is changed by changing the voltage applied between the first transparent electrode layer and the second transparent electrode layer. The dimming layer has an ionizing radiation curing resin layer that divides a gap and a liquid crystal composition filled in the gap, and acryloyl and methacryloyl are functional groups. Among the acrylic compounds constituting the ionizing radiation curing resin layer, an acrylic compound having three or more of the above functional groups and a double bond equivalent of 150 g / eq or less is the first acrylic compound, and the content of the first acrylic compound constituting the ionizing radiation curing resin layer is 2% by mass or more of the above ionizing radiation curing resin layer.

[0019] The method for manufacturing a dimming sheet for solving the above technical problems comprises: forming a coating layer containing an ionizing radiation curable composition and a liquid crystal composition between a first transparent electrode layer and a second transparent electrode layer; and forming a dimming layer between the first transparent electrode layer and the second transparent electrode layer by irradiating the coating layer with ionizing radiation, wherein the dimming layer comprises an ionizing radiation curable resin layer dividing a gap and the liquid crystal composition filled in the gap, and the haze of the dimming layer is changed by changing the voltage applied between the first transparent electrode layer and the second transparent electrode layer. Acryloyl and methacryloyl are functional groups, and among the acrylic compounds constituting the ionizing radiation curable resin layer, an acrylic compound having three or more of the functional groups and a double bond equivalent of 150 g / eq or less is the first acrylic compound, and the content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more of the ionizing radiation curable resin layer.

[0020] According to the above configurations, the first acrylic compound having three or more functional groups and a double bond equivalent of 150 g / eq or less in the acrylic compound constituting the ionizing radiation curable resin layer accounts for more than 2% by mass of the ionizing radiation curable resin layer, so the ionizing radiation curable resin layer inhibits low molecular weight impurities contained in the alignment layer from reaching the liquid crystal compound. As a result, the heat resistance of the optical characteristics in the dimming sheet can be improved.

[0021] Effects of the Invention

[0022] The dimming film, dimming device, and dimming film manufacturing method disclosed in the present invention can broaden the temperature range that is limited for driving the dimming film. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a diagram of the structure of the dimming device.

[0024] Figure 2 This is an enlarged cross-sectional view of the dimming film.

[0025] Figure 3 The contents of acrylic acid compounds and evaluation results in the test examples are shown.

[0026] Figure 4 The contents of acrylic acid compounds and evaluation results in the test examples are shown.

[0027] Figure 5 Shows the first acrylic compound dependence in the low temperature response.

[0028] Figure 6 The first acrylic compound dependency of the peel strength is shown.

[0029] Figure 7 The dependence of the peel strength on the acrylic compound ratio is shown.

[0030] Figure 8 The dependence of the haze after the heat treatment on the first acrylic compound is shown.

[0031] Fig. 9 The dependence of the haze after heat treatment on the mixing ratio of the acrylic compound is shown.

[0032] Fig.10 The first acrylic compound dependency and EO modification dependency among the evaluation results are shown. DETAILED DESCRIPTION

[0033] [Dimming device 10]

[0034] like Figure 1 As shown, the dimming device 10 includes a dimming sheet 11 and a driving unit 12 .

[0035] The dimming device 10 can be used as a partition device for dividing spaces. The dimming sheet 11 itself can be a partition component for dividing spaces, or a dimming laminated body in which the dimming sheet 11 is installed in a transparent component can be a partition component for dividing spaces. The partition component can be a window glass or a partition. The window glass can be mounted in a mobile body such as a vehicle or an airplane, or can be set in a building such as an office building or a public facility. The partition can be arranged in a vehicle space or in an indoor space.

[0036] The dimming device 10 can also be used as a screen for displaying images. The dimming sheet 11 itself can be the screen, or a dimming laminated body in which the dimming sheet 11 is installed in a transparent component can be the screen. The screen can be a front screen that uses reflected light in the image, or a rear screen that uses transmitted light in the image.

[0037] The dimming laminate can be installed with one dimming sheet 11 in one transparent component, or multiple dimming sheets 11 can be installed in one transparent component. The dimming laminate can also hold the dimming sheet 11 between two transparent substrates. The dimming sheet 11 is flexible. The dimming laminate can be flexible or inflexible. The dimming laminate can be flat or curved.

[0038] The driving mode of the dimming film 11 may be a reverse type. The driving unit 12 supplies a voltage signal to the reverse dimming film 11. The reverse dimming film 11 changes from transparent to opaque as the voltage signal is input. The reverse dimming film 11 remains opaque during the input of the voltage signal. The reverse dimming film 11 returns from opaque to transparent as the supply of the voltage signal stops.

[0039] The driving mode of the dimming film 11 can also be a forward type. The driving unit 12 supplies a voltage signal to the forward dimming film 11. The forward dimming film 11 changes from opaque to transparent as the voltage signal is input. The forward dimming film 11 remains transparent during the input of the voltage signal. The forward dimming film 11 returns from transparent to opaque as the supply of the voltage signal stops.

[0040] The dimming film 11 is opaque by scattering the transmitted light brought by the dimming film 11. The opaque dimming film 11 has a lower parallel line transmittance than the transparent dimming film 11. The opaque dimming film 11 has a higher haze than the transparent dimming film 11. The color of the opaque dimming film 11 can be achromatic or colorful. The color of the transparent dimming film 11 can be achromatic or colorful.

[0041] [Dimming film 11]

[0042] The following mainly describes the structure and function of the reverse type dimming film 11. The structures of the forward type dimming film 11 that are different from the reverse type dimming film 11 are described, and the structures of the forward type dimming film 11 that overlap with the reverse type dimming film 11 are omitted.

[0043] The light modulating sheet 11 includes a light modulating layer 31 , a first alignment layer 32 , a second alignment layer 33 , a first transparent electrode layer 34 , a second transparent electrode layer 35 , a first transparent supporting layer 36 , and a second transparent supporting layer 37 .

[0044] The light-adjusting layer 31 is located between the first orientation layer 32 and the second orientation layer 33. The first surface 31F of the light-adjusting layer 31 contacts the first orientation layer 32. The second surface 31S of the light-adjusting layer 31 contacts the second orientation layer 33. The first orientation layer 32 is located between the light-adjusting layer 31 and the first transparent electrode layer 34 and contacts the light-adjusting layer 31 and the first transparent electrode layer 34. The second orientation layer 33 is located between the light-adjusting layer 31 and the second transparent electrode layer 35 and contacts the light-adjusting layer 31 and the second transparent electrode layer 35.

[0045] The first transparent electrode layer 34 is connected to the drive unit 12 through the first connection terminal 22A and the first wiring 23A. The first transparent electrode layer 34 is located between the first alignment layer 32 and the first transparent supporting layer 36 and is in contact with the first alignment layer 32 and the first transparent supporting layer 36.

[0046] The second transparent electrode layer 35 is connected to the drive unit 12 through the second connection terminal 22B and the second wiring 23B. The second transparent electrode layer 35 is located between the second alignment layer 33 and the second transparent supporting layer 37 and is in contact with the second alignment layer 33 and the second transparent supporting layer 37 .

[0047] The first transparent electrode layer 34 and the second transparent electrode layer 35 appear to be colorless and transparent, or colored and transparent, respectively. The materials constituting the first transparent electrode layer 34 and the second transparent electrode layer 35 are conductive inorganic oxides, metals, or conductive organic polymer compounds, respectively. An example of a conductive inorganic oxide is any one selected from indium tin oxide, fluorine-doped tin oxide, tin oxide, and zinc oxide. The metal is a nanowire of gold or silver. An example of a conductive organic polymer compound is any one selected from carbon nanotubes and poly(3,4-ethylenedioxythiophene). An example of the thickness of the first transparent electrode layer 34 and the second transparent electrode layer 35 is respectively greater than 5 nm and less than 200 nm.

[0048] The first transparent support layer 36 and the second transparent support layer 37 appear to be colorless and transparent, or colored and transparent. The materials constituting the first transparent support layer 36 and the second transparent support layer 37 are respectively organic polymer compounds or inorganic polymer compounds. An example of the organic polymer compound is any one selected from polyester, polyacrylate, polycarbonate, and polyolefin. An example of the inorganic polymer compound is any one selected from silicon oxide, silicon nitride oxide, and silicon nitride. An example of the thickness of the first transparent support layer 36 and the second transparent support layer 37 is respectively 20 μm or more and 400 μm or less.

[0049] The driving unit 12 is connected to the first transparent electrode layer 34 and the second transparent electrode layer 35, respectively. The driving unit 12 applies a voltage between the first transparent electrode layer 34 and the second transparent electrode layer 35 by supplying a voltage signal. The driving unit 12 changes the voltage between the first transparent electrode layer 34 and the second transparent electrode layer 35 by stopping the supply of the voltage signal. The supply and stop of the supply of the voltage signal change the orientation state of the liquid crystal compound LCM. The driving unit 12 reversibly switches the dimming sheet 11 from transparent to opaque by changing the orientation state of the liquid crystal compound LCM.

[0050] When the driving unit 12 stops supplying the voltage signal, the orientation state of the liquid crystal compound LCM complies with the orientation restriction force brought by the first orientation layer 32 and the second orientation layer 33. The orientation state of the liquid crystal compound LCM that complies with the orientation restriction force allows visible light to pass through the dimming layer 31. As a result, the dimming film 11 becomes transparent. When the driving unit 12 supplies the voltage signal, the liquid crystal compound LCM is acted upon by the electric field that resists the orientation restriction force. The orientation state of the liquid crystal compound LCM that complies with the electric field force causes visible light to be scattered in the dimming layer 31. As a result, the dimming film 11 becomes opaque.

[0051] The dimming sheet 11 may include other functional layers between the first transparent electrode layer 34 and the first transparent support layer 36. The dimming sheet 11 may include other functional layers between the second transparent electrode layer 35 and the second transparent support layer 37. The other functional layers may be gas barrier layers that can inhibit oxygen or moisture from passing through the dimming layer 31, or ultraviolet blocking layers that can inhibit ultraviolet light other than a specific wavelength from passing through the dimming layer 31. The other functional layers may also be hard coating layers that mechanically protect the dimming sheet 11, or adhesive layers that can improve the interlayer adhesion of the dimming sheet 11.

[0052] [Dimming layer 31]

[0053] like Figure 2 As shown, the light-adjusting layer 31 includes a liquid crystal composition 31LC, a spacer SP, and an ionizing radiation curable resin layer 31P.

[0054] The liquid crystal composition 31LC includes a liquid crystal compound LCM. The liquid crystal composition 31LC may contain additives such as a dichroic pigment DP, a defoamer, an antioxidant, a weathering agent, and a solvent. An example of a weathering agent is an ultraviolet absorber or a light stabilizer. The liquid crystal composition 31LC does not contain a viscosity reducer that reduces the viscosity of the liquid crystal composition 31LC to a viscosity lower than that of the liquid crystal compound LCM. The viscosity reducer is selected from adipic acid dibutyl ester, bis (2-ethylhexyl) adipate, diisononyl adipate, diisodecyl adipate, bis (2-butoxyethyl) adipate and other adipic acid esters. The viscosity reducer is selected from at least one of adipic acid ester, diethyl malonate, di-n-butyl phthalate, bis (2-ethylhexyl) phthalate, tris (2-ethylhexyl) trimellitate, o-acetyl tributyl citrate, and methyl benzoate. The viscosity reducer is selected from at least one of tripropyl phosphate, tributyl phosphate, and tripentyl phosphate. Furthermore, when further improvement of the responsiveness in a low-temperature environment is required, the liquid crystal composition 31LC may contain a viscosity lowering agent.

[0055] The liquid crystal compound LCM may have a positive dielectric anisotropy in which the dielectric constant in the long axis direction is larger than the dielectric constant in the short axis direction. The liquid crystal compound LCM may also have a negative dielectric anisotropy in which the dielectric constant in the long axis direction is lower than the dielectric constant in the short axis direction. The dielectric anisotropy of the liquid crystal compound LCM is appropriately selected according to the driving mode of the dimming plate 11.

[0056] The liquid crystal compound LCM is at least one selected from Schiff base, azo, azoxy, biphenyl, terphenyl, benzoate, tolan, pyrimidine, pyridazine, cyclohexanecarboxylate, phenylcyclohexane, biphenylcyclohexane, dicyanobenzene, naphthalene, and dioxane. The liquid crystal compound LCM is one liquid crystal compound LCM or a combination of two or more liquid crystal compounds LCM.

[0057] The structural example of the liquid crystal compound LCM is represented by Formula 1 below.

[0058] R 11 -A 11 -Z 11 -A 12 -Z 12 -A 13 -Z 13 -A 14 -R 12 Formula 1

[0059] R shown in formula 1 11 is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. 11One or two or more non-adjacent methylene bonds contained in the alkyl group may be substituted with any one selected from the group consisting of an oxygen atom, an ethylene bond, an ester bond, and a diether bond. 12 is a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, a trifluoromethyl group, a trifluoromethoxy group, a difluoromethoxy group, or an alkyl group having 1 to 15 carbon atoms. 12 One or two or more non-adjacent methylene bonds contained in the alkyl group may be substituted with any one selected from the group consisting of an oxygen atom, an ethylene bond, an ester bond, and a diether bond.

[0060] A shown in formula 1 11 , A 12 , A 13 , A 14 Each independently represents 1,4-phenylene or 2,6-naphthylene. One or more hydrogen atoms of 1,4-phenylene or 2,6-naphthylene may be substituted with fluorine atoms, chlorine atoms, trifluoromethyl or trifluoromethoxy. 11 , A 12 , A 13 , A 14 Each independently may be 1,4-cyclohexylene, 3,6-cyclohexenylene, 1,3-dihexane-2,5-diyl, or pyridine-2,5-diyl. 13 , A 14 Each independently may be a single bond. 11 , Z 12 , Z 13 Each independently represents any one of a single bond, an ester bond, a diether bond, an ethylene bond, a fluoroethylene bond, and a carbonyl bond.

[0061] The dichroic pigment DP is driven by a guest-host mode with the liquid crystal compound LCM as the main body and presents color. The dichroic pigment DP is at least one selected from high iodine, azo compounds, anthraquinone compounds, naphthoquinone compounds, azomethine compounds, tetrazine compounds, quinoline yellow compounds, merocyanine compounds, perylene compounds, and dioxazine compounds. The dichroic pigment DP is a compound or a combination of two or more compounds. When it is required to improve light resistance and improve the two-color ratio, the dichroic pigment DP is at least one selected from azo compounds and anthraquinone compounds, and is more preferably an azo compound.

[0062] The spacers SP are dispersed throughout the entire ionizing radiation-cured resin layer 31P. The spacers SP define the thickness of the light-adjusting layer 31 according to the particle size of the spacers SP. An example of the thickness of the light-adjusting layer 31 is greater than 5 μm and less than 100 μm. The spacers SP make the thickness of the light-adjusting layer 31 uniform. The spacers SP may be bead spacers or photospacers formed by exposure and development of a photoresist. The spacers SP may be colorless and transparent or colored and transparent. When the liquid crystal composition 31LC includes a dichroic pigment DP, the color of the spacer SP is preferably the same color as the color presented by the dichroic pigment DP.

[0063] [Ionizing radiation curing resin layer 31P]

[0064] The ionizing radiation curing resin layer 31P is a cured product of an ionizing radiation curing composition. The ionizing radiation may be ultraviolet rays or electron beams. The ionizing radiation curing composition may be an ultraviolet curing composition or an electron beam curing composition. The lower limit of the content of the ionizing radiation curing resin layer 31P relative to the total amount of the ionizing radiation curing resin layer 31P and the liquid crystal composition 31LC is 20% by mass, and a more preferred lower limit of the content is 30% by mass. If the content of the ionizing radiation curing resin layer 31P is 20% by mass or more, high transmittance is easily obtained when transparent. The upper limit of the content of the ionizing radiation curing resin layer 31P relative to the total amount of the ionizing radiation curing resin layer 31P and the liquid crystal composition 31LC is 70% by mass, and a more preferred upper limit of the content is 60% by mass. If the content of the ionizing radiation curing resin layer 31P is 70% by mass or less, high haze is easily obtained when opaque.

[0065] The lower limit and upper limit of the content of the ionizing radiation curing resin layer 31P are the ranges in which the liquid crystal particles formed by the liquid crystal composition 31LC phase separate from the polymer of the ionizing radiation curing composition during the polymerization of the ionizing radiation curing composition. When the mechanical strength of the ionizing radiation curing resin layer 31P is required to be improved, the lower limit of the content of the ionizing radiation curing resin layer 31P is preferably high. When the driving voltage of the liquid crystal compound LCM is required to be reduced, the upper limit of the content of the ionizing radiation curing resin layer 31P is preferably low. The content of the ionizing radiation curing resin layer 31P relative to the total amount of the ionizing radiation curing resin layer 31P and the liquid crystal composition 31LC can be 20% by mass or more and 70% by mass or less, or 30% by mass or more and 70% by mass or less. The content of the ionizing radiation curing resin layer 31P relative to the total amount of the ionizing radiation curing resin layer 31P and the liquid crystal composition 31LC can also be 20% by mass or more and 60% by mass or less, or 30% by mass or more and 60% by mass or less.

[0066] The ionizing radiation-cured resin layer 31P divides the gap 31D in the dimming layer 31. The liquid crystal composition 31LC is filled in the gap 31D. The gap 31D can be isolated from other gaps 31D adjacent to the gap 31D, and can also be connected to other adjacent gaps 31D. The size of the gap 31D is two or more. The shape of the gap 31D is spherical, ellipsoidal, or indefinite. The diameter of the sphere circumscribed in the gap 31D can be greater than 0.4μm, and can also be greater than 1μm. The diameter of the sphere circumscribed in the gap 31D can be less than 20μm, and can also be less than 10μm. The diameter of the sphere circumscribed in the gap 31D is, for example, greater than 1μm and less than 10μm.

[0067] The voids 31D may be unevenly present in the ionizing radiation curing resin layer 31P, or may be uniformly dispersed in the ionizing radiation curing resin layer 31P. The voids 31D may be unevenly present in a manner that the more the voids are present in a region 31H1 closer to the first orientation layer 32 than the center in the thickness direction of the ionizing radiation curing resin layer 31P, the more the voids are present in a region 31H2 closer to the second orientation layer 3 ... The ionizing radiation curable resin layer 31P may further include a portion where the void 31D does not exist at the center in the thickness direction of the ionizing radiation curable resin layer 31P, and a void 31D may be provided between the portion and the second alignment layer 33 .

[0068] The gap 31D is formed by the phase separation of the cured product of the ionizing radiation curable composition and the liquid crystal composition 31LC. In the ionizing radiation curable resin layer 31P, the range 31H1 closer to the first orientation layer 32 than the center in the thickness direction is the part where the ionizing radiation begins to be irradiated, and is the part where the gap 31D begins to be formed. In the ionizing radiation curable resin layer 31P, the range 31H2 closer to the second orientation layer 33 than the center in the thickness direction is also the part where the ionizing radiation begins to be irradiated, and is also the part where the gap 31D begins to be formed.

[0069] In the ionizing radiation cured resin layer 31P, the range 31H1 closer to the first orientation layer 32 than the center in the thickness direction is also a site where low molecular weight impurities start to diffuse from the first orientation layer 32. In the ionizing radiation cured resin layer 31P, the range 31H2 closer to the second orientation layer 33 than the center in the thickness direction is also a site where low molecular weight impurities start to diffuse from the second orientation layer 33. Therefore, the structure in which the voids 31D are biased in the range 31H1 close to the first orientation layer 32, that is, the structure in which the liquid crystal composition 31LC is biased in the range 31H1 close to the first orientation layer 32, strongly requires the diffusion of low molecular weight impurities. In addition, the structure in which the voids 31D are biased in the range 31H2 close to the second orientation layer 33, that is, the structure in which the liquid crystal composition 31LC is biased in the range 31H2 close to the second orientation layer 33, also strongly requires the diffusion of low molecular weight impurities.

[0070] The phase separation between the cured product of the ionizing radiation curable composition and the liquid crystal composition 31LC causes unreacted ionizing radiation curable compounds, byproducts such as water caused by the curing reaction of the ionizing radiation curable compounds, and low molecular weight compounds such as solvents of the ionizing radiation curable composition to remain in the liquid crystal composition 31LC. The degree to which the viscosity of the ionizing radiation curable compounds, byproducts such as water, and low molecular weight compounds such as solvents increases due to a decrease in temperature is greater than the degree to which the viscosity of the liquid crystal compound LCM increases due to a decrease in temperature in a low temperature environment such as a cold place. In the process of phase separation between the cured product of the ionizing radiation curable composition and the liquid crystal composition 31LC, making the cured product of the ionizing radiation curable composition dense can suppress the low molecular weight compounds from remaining in the liquid crystal composition 31LC. The suppression of the residual low molecular weight compounds in the liquid crystal composition 31LC can suppress the increase in viscosity of the liquid crystal composition 31LC in a low temperature environment.

[0071] The holding mode of the liquid crystal composition 31LC using the ionizing radiation curing resin layer 31P is any one selected from the group consisting of a polymer dispersion type, a polymer network type, and a capsule type. The polymer dispersion type dimming layer 31 includes an ionizing radiation curing resin layer 31P that divides a plurality of isolated voids 31D. The polymer dispersion type dimming layer 31 holds the liquid crystal composition 31LC in the voids 31D dispersed in the ionizing radiation curing resin layer 31P. The polymer network type dimming layer 31 includes voids 31D having a three-dimensional mesh shape in the ionizing radiation curing resin layer 31P. The polymer network type dimming layer 31 holds the liquid crystal composition 31LC in the mesh-like voids 31D that are interconnected. The capsule type dimming layer 31 holds the liquid crystal composition 31LC in the capsule-like voids 31D dispersed in the ionizing radiation curing resin layer 31P.

[0072] The ionizing radiation curable resin layer 31P is formed by coating a light-adjusting coating liquid containing an ionizing radiation curable composition and a liquid crystal composition 31LC and irradiating the coating layer with ionizing radiation. The light-adjusting coating liquid contains a polymerization initiator for initiating polymerization of the ionizing radiation curable composition. The ionizing radiation curable resin layer 31P contains a polymerization initiator for initiating polymerization. The polymerization initiator is at least one selected from diketone compounds, acetophenone compounds, benzoin compounds, benzophenone compounds, and thioxanthone compounds. The polymerization initiator can be one compound or a combination of two or more compounds. An example of a polymerization initiator is any one selected from benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and cyclohexyl phenyl ketone.

[0073] [First acrylic compound]

[0074] The ionizing radiation curable composition contains a first acrylic compound. The first acrylic compound has more than 3 functional groups and a double bond equivalent of less than 150 g / eq. The functional groups are acryloyl and methacryloyl. The double bond equivalent is a value calculated by dividing the molecular weight of the first acrylic compound by the number of functional groups. The number of functional groups is the sum of the number of acryloyl groups and the number of methacryloyl groups contained in the first acrylic compound. The first acrylic compound can be contained in the electron beam curable compound as a monomer. The first acrylic compound can also be contained in the electron beam curable compound as a constituent element of carbamate acrylates such as carbamate prepolymers. When the first acrylic compound is a constituent element of carbamate acrylate, the double bond equivalent is determined according to the skeleton structure of the first acrylic compound in the carbamate acrylate.

[0075] An example of the first acrylic compound is a pentaerythritol compound, a trimethylolpropane compound, and a diol compound. The pentaerythritol compound is pentaerythritol diacrylate, pentaerythritol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, pentaerythritol ethoxy tetraacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol ethoxy tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, and tripentaerythritol octaacrylate. The trimethylolpropane compound is trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, trimethylolpropane ethoxy triacrylate, di(trimethylolpropane) tetraacrylate, and di(trimethylolpropane) tetramethacrylate. The diol compound is glycerol diacrylate, glycerol triacrylate, glycerol trimethacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, and 1,6-hexanediol diacrylate. An example of the prepolymer containing the first acrylic compound is pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer.

[0076] The ionizing radiation curable composition may also contain a free radical curing aid. The ionizing radiation curing resin layer 31P may also contain a free radical curing aid. The free radical curing aid can improve the polymerizability of the acrylic compound. The polymerization of the acrylic compound stops polymerization by generating peroxide radicals. An example of a free radical curing aid contains a thiol group. The thiol group of the free radical curing aid promotes the polymerization of the acrylic compound by providing hydrogen to the peroxide radical. An example of a free radical curing aid may be a primary multifunctional thiol compound or a secondary multifunctional thiol compound. An example of a primary multifunctional thiol compound is pentaerythritol tetrakis (3-mercaptopropionate) and tetraethylene glycol bis (3-mercaptopropionate). An example of a secondary multifunctional thiol compound is pentaerythritol tetrakis (3-mercaptobutyrate).

[0077] [Second acrylic compound]

[0078] The ionizing radiation curable composition contains a second acrylic compound. The second acrylic compound is a monofunctional alkyl acrylate, a monofunctional alkyl methacrylate, a monofunctional alkoxyalkyl acrylate, and a monofunctional alkoxyalkyl methacrylate. The monofunctional alkyl acrylate and the monofunctional alkyl methacrylate refer to saturated alkyl groups each containing 2 to 12 carbon atoms. The monofunctional alkoxyalkyl acrylate and the monofunctional alkoxyalkyl methacrylate refer to saturated alkoxyalkyl groups each containing 2 to 12 carbon atoms. The saturated alkyl group may be a straight-chain alkyl group, a branched-chain alkyl group, a monocyclic alkyl group, or a polycyclic alkyl group. The saturated alkoxyalkyl group may be a straight-chain alkoxyalkyl group or a branched-chain alkoxyalkyl group.

[0079] An example of the second acrylic compound is ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, 2-ethylbutyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, methoxyethyl methacrylate, octyl acrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylbutyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, lauryl methacrylate, cyclohexyl acrylate, cyclopentyl acrylate, dicyclopentyl acrylate, bornyl acrylate, bornyl methacrylate, isobornyl acrylate, and isobornyl methacrylate.

[0080] [Third acrylic compound]

[0081] The ionizing radiation curable composition contains a third acrylic compound. The third acrylic compound has more than 1 and less than 3 functional groups and a polyethylene oxide chain, and the double bond equivalent is more than 300 g / eq and less than 700 g / eq. The functional groups are acryloyl and methacryloyl. The double bond equivalent is a value calculated by dividing the molecular weight of the third acrylic compound by the number of functional groups. The number of functional groups is the sum of the number of acryloyl groups and the number of methacryloyl groups contained in the third acrylic compound. The third acrylic compound can be contained in the electron beam curable compound as a monomer. The third acrylic compound can also be contained in the electron beam curable compound as a constituent element of urethane acrylates such as urethane prepolymers.

[0082] An example of the third acrylic compound may be a polyethylene glycol compound, an alkoxy polyethylene glycol compound, or a polyethylene oxide modified trimethylolpropane compound (EO modified trimethylolpropane compound). An example of the third acrylic compound is polyethylene glycol acrylate, polyethylene glycol methacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol acrylate, polypropylene glycol methacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, methoxy polyethylene glycol acrylate, methoxy polypropylene glycol acrylate, EO modified trimethylolpropane triacrylate, EO modified trimethylolpropane trimethacrylate, EO modified di (trimethylolpropane) tetraacrylate, EO modified di (trimethylolpropane) tetramethacrylate.

[0083] [Content ratio of acrylic acid compound]

[0084] The ionizing radiation curable composition satisfies the following conditions 1, 2, and 3 simultaneously. Or the ionizing radiation curable composition satisfies the following conditions 1, 2, and 4 simultaneously. The ionizing radiation curable composition may also satisfy the following conditions 1A, 2A, and 3 simultaneously. The ionizing radiation curable composition may also satisfy the following conditions 1A, 2A, and 4 simultaneously. In addition, the ionizing radiation curable composition may also satisfy the following conditions 1B, 2B, and 3 simultaneously. The ionizing radiation curable composition may also satisfy the following conditions 1B, 2B, and 4 simultaneously. Furthermore, the ionizing radiation curable composition may also satisfy the following condition 5, and may also satisfy the following condition 6.

[0085] [Condition 1] The content of the first acrylic compound is 2 mass % or more and 50 mass % or less.

[0086] [Condition 1A] The content of the first acrylic compound is 2 mass % or more and 40 mass % or less.

[0087] [Condition 1B] The content of the first acrylic compound is 2 mass % or more and 30 mass % or less.

[0088] [Condition 2] The content of the second acrylic compound is 35 mass % or more and 85 mass % or less.

[0089] [Condition 2A] The content of the second acrylic compound is 45% by mass or more and 85% by mass or less.

[0090] [Condition 2B] The content of the second acrylic compound is 55% by mass or more and 85% by mass or less.

[0091] [Condition 3] The content of the third acrylic compound is 5 mass % or more and 20 mass % or less.

[0092] [Condition 4] The acrylic acid compound mixing ratio is 0.25 or more.

[0093] [Condition 4A] The acrylic acid compound blending ratio is 0.25 or more and 2.0 or less.

[0094] [Condition 5] The number of functional groups of the first acrylic compound is 3 or more and 5 or less, and the content of the first acrylic compound is 30% by mass or less.

[0095] [Condition 6] The content of the polyethylene oxide chain is 2 mass % or more and 20 mass % or less.

[0096] The content of the first acrylic compound is the ratio of the weight of the first acrylic compound to the total weight of the ionizing radiation curable composition used to form the ionizing radiation curable resin layer 31P. The total weight of the ionizing radiation curable composition is the sum of the weight of the first acrylic compound, the weight of the radical curing aid, the weight of the second acrylic compound, and the weight of the third acrylic compound.

[0097] The content rate of the second acrylic compound is the ratio of the weight of the second acrylic compound to the total weight of the ionizing radiation curable composition for forming the ionizing radiation curable resin layer 31P.

[0098] The content rate of the third acrylic compound is the ratio of the weight of the third acrylic compound to the total weight of the ionizing radiation curable composition for forming the ionizing radiation curable resin layer 31P.

[0099] The content of the polyethylene oxide chain is the ratio of the weight of the polyethylene oxide chain to the total weight of the ionizing radiation curable composition for forming the ionizing radiation curable resin layer 31P.

[0100] The acrylic compound blending ratio is the content of the third acrylic compound relative to the content of the first acrylic compound.

[0101] [First alignment layer 32, second alignment layer 33]

[0102] The first alignment layer 32 and the second alignment layer 33 respectively limit the alignment direction of the liquid crystal compound LCM. The first alignment layer 32 and the second alignment layer 33 respectively appear to be colorless and transparent, or colored and transparent. The first alignment layer 32 and the second alignment layer 33 can be vertical alignment films or horizontal alignment films.

[0103] The material constituting the first orientation layer 32 and the second orientation layer 33 is an organic polymer compound or an inorganic oxide. An example of an organic polymer compound is any one selected from polyimide, polyamide, and polyvinyl alcohol. An example of an inorganic oxide is any one selected from silicon oxide, zirconium oxide, and organosilicon. The material constituting the first orientation layer 32 and the second orientation layer 33 contains low molecular impurities used to generate organic polymer compounds or inorganic oxides. An example of low molecular impurities can be a polyimide precursor such as polyamic acid used in the generation of polyimide, or water generated by imidization of polyamic acid. An example of the thickness of the first orientation layer 32 and the second orientation layer 33 is respectively greater than 20nm and less than 500nm.

[0104] When the first alignment layer 32 and the second alignment layer 33 are respectively vertical alignment films, the first alignment layer 32 and the second alignment layer 33 respectively apply alignment restricting forces to the liquid crystal compound LCM in such a way that the long axis direction of the liquid crystal compound LCM is along the thickness direction of the light-adjusting layer 31. Thus, the first alignment layer 32 and the second alignment layer 33 allow visible light to pass through the light-adjusting layer 31 during the period when the supply of the voltage signal is stopped.

[0105] When the first alignment layer 32 and the second alignment layer 33 are horizontal alignment films, the light modulating sheet 11 includes a polarizing layer. The first alignment layer 32 and the second alignment layer 33 exert an alignment restricting force on the liquid crystal compound LCM so that the long axis direction of the liquid crystal compound LCM and the extending direction of the transmission axis of the polarizing layer become parallel. Thus, the first alignment layer 32 and the second alignment layer 33 allow visible light to pass through the light modulating layer 31 through the polarizing layer during the period when the supply of the voltage signal is stopped.

[0106] When the first orientation layer 32 and the second orientation layer 33 are respectively horizontal orientation films, the dimming film 11 has polarization layers configured as orthogonal Nicols. The first orientation layer 32 applies an orientation restriction force to the liquid crystal compound LCM in such a way that the long axis direction of the liquid crystal compound LCM becomes parallel to the extension direction of the transmission axis of one polarization layer. The second orientation layer 33 applies an orientation restriction force to the liquid crystal compound LCM in such a way that the long axis direction of the liquid crystal compound LCM becomes parallel to the extension direction of the transmission axis of another polarization layer. That is, the first orientation layer 32 and the second orientation layer 33 apply a rotational orientation restriction force to the liquid crystal compound LCM. Thus, the first orientation layer 32 and the second orientation layer 33 allow visible light to pass through the polarization layer and the dimming layer 31 during the period when the supply of the voltage signal is stopped.

[0107] In addition, when the first orientation layer 32 and the second orientation layer 33 are respectively horizontal orientation films, the dimming film 11 has two polarization layers with mutually parallel transmission axes. The first orientation layer 32 and the second orientation layer 33 apply an orientation restriction force to the liquid crystal compound LCM in such a manner that the long axis direction of the liquid crystal compound LCM intersects at 45 degrees in the extension direction of the transmission axis of the polarization layer. As a result, the first orientation layer 32 and the second orientation layer 33 suppress the visible light that has passed through the polarization layer from passing through the dimming layer 31 during the period when the supply of the voltage signal is stopped. The voltage applied between the first transparent electrode layer 34 and the second transparent electrode layer 35 imparts a vertical orientation to the liquid crystal compound LCM that resists the orientation restriction force, so that the visible light that has passed through the polarization layer passes through the dimming layer 31.

[0108] In addition, the light modulating film 11 may also be separated from the first alignment layer 32 and the second alignment layer 33. The light modulating layer 31 of the light modulating film 11 without the first alignment layer 32 and the second alignment layer 33 may contact the first transparent electrode layer 34 or the second transparent electrode layer 35.

[0109] [Method for Manufacturing the Light Regulating Sheet 11]

[0110] The method for manufacturing the dimming sheet 11 includes the step of forming a dimming coating layer including an ionizing radiation curable composition and a liquid crystal composition 31LC between a first transparent electrode layer 34 and a second transparent electrode layer 35. The method for manufacturing the dimming sheet 11 includes the step of forming a dimming layer 31 between the first transparent electrode layer 34 and the second transparent electrode layer 35 by irradiating the dimming coating layer with ionizing radiation.

[0111] When the dimming sheet 11 includes the first orientation layer 32 and the second orientation layer 33, the manufacturing method of the dimming sheet 11 includes the step of forming the first orientation layer 32 on the first transparent electrode layer 34, and the step of forming the second orientation layer 33 on the second transparent electrode layer 35. The first orientation layer 32 is formed by coating the first transparent electrode layer 34 stacked on the first transparent support layer 36 with an orientation coating liquid to form an orientation coating layer, and heating the orientation coating layer. The second orientation layer 33 is formed by coating the second transparent electrode layer 35 stacked on the second transparent support layer 37 with an orientation coating liquid to form an orientation coating layer, and heating the orientation coating layer.

[0112] The manufacturing method of the dimming sheet 11 includes the step of forming a dimming coating layer including an ionizing radiation curable composition and a liquid crystal composition 31LC between a first orientation layer 32 and a second orientation layer 33. The dimming coating layer is formed by coating a dimming coating liquid on the first orientation layer 32 supported by a first transparent support layer 36. The dimming coating layer is sandwiched between the first orientation layer 32 supported by the first transparent support layer 36 and the second orientation layer 33 supported by the second transparent support layer 37. In addition, when the dimming sheet 11 does not include the first orientation layer 32 and the second orientation layer 33, the dimming coating layer is formed by coating a dimming coating liquid on the first transparent electrode layer 34 supported by the first transparent support layer 36. The dimming coating layer is sandwiched between the first transparent electrode layer 34 supported by the first transparent support layer 36 and the second transparent electrode layer 35 supported by the second transparent support layer 37.

[0113] The manufacturing method of the dimming sheet 11 includes the step of forming a dimming layer 31 between a first transparent electrode layer 34 and a second transparent electrode layer 35 by irradiating the dimming coating layer with ionizing radiation, wherein the dimming layer 31 includes an ionizing radiation-cured resin layer 31P that divides a gap 31D and a liquid crystal composition 31LC that fills the gap 31D. The dimming coating layer may be irradiated with ionizing radiation from the first transparent support layer 36, or from the second transparent support layer 37, or by a combination thereof.

[0114] The ionizing radiation curable composition irradiated with ionizing radiation initiates polymerization while causing phase separation of the liquid crystal particles formed by the liquid crystal composition 31LC from the polymer. The phase separation of the liquid crystal particles formed by the liquid crystal composition 31LC is carried out by polymerization of the ionizing radiation curable composition and diffusion of the liquid crystal composition 31LC. The polymerization rate of the ionizing radiation curable composition changes with the intensity of the ionizing radiation irradiated to the ionizing radiation curable composition. The diffusion rate of the liquid crystal composition 31LC changes with the treatment temperature during the polymerization of the ionizing radiation curable composition. In the phase separation of the liquid crystal composition 31LC, the intensity of the ionizing radiation irradiated to the ionizing radiation curable composition is set in such a way that the size of the liquid crystal particles becomes the desired size, that is, the size of the gap 31D becomes the desired size. In addition, in the phase separation of the liquid crystal composition 31LC, heating for promoting the diffusion of the liquid crystal composition 31LC can also be performed.

[0115] When the size of the gap 31D is required to be reduced, it is preferred to increase the intensity of the ionizing radiation irradiated to the ionizing radiation curable composition, and promote polymerization at a low temperature for suppressing the diffusion of the liquid crystal composition 31LC. When the size of the gap 31D is required to be increased, it is preferred to reduce the intensity of the ionizing radiation irradiated to the ionizing radiation curable composition, and promote polymerization at a high temperature for promoting the diffusion of the liquid crystal composition 31LC.

[0116] [Test example]

[0117] The dimming sheet 11 of each test example is shown below. In addition, the dimming sheet 11 of each test example has a vertical orientation film as the first orientation layer 32 and the second orientation layer 33. The driving mode of each test example is a reverse type. The dimming sheets 11 of Test Examples 1 to 13 use different ionizing radiation curable compositions, respectively, and are obtained in the same manner except that the ionizing radiation curable compositions are different. The dimming sheets 11 of Test Examples 14 to 17 use different ionizing radiation curable compositions and liquid crystal compositions 31LC, respectively, and are obtained in the same manner except that the ionizing radiation curable compositions and liquid crystal compositions 31LC are different.

[0118] First, constituent materials of the first transparent electrode layer 34 , the second transparent electrode layer 35 , the first transparent supporting layer 36 , and the second transparent supporting layer 37 are shown below.

[0119] First transparent electrode layer 34: Indium tin oxide with a thickness of 30 nm

[0120] Second transparent electrode layer 35: Indium tin oxide with a thickness of 30 nm

[0121] First transparent support layer 36: polyethylene terephthalate film with a thickness of 125 μm

[0122] Second transparent support layer 37: polyethylene terephthalate film with a thickness of 125 μm

[0123] [First alignment layer 32, second alignment layer 33]

[0124] Next, constituent materials and formation methods of the first alignment layer 32 and the second alignment layer 33 are described below.

[0125] First, polyamic acid is generated in a solvent from the diamine represented by the following raw materials B1 and B2 and the carboxylic anhydride represented by the following raw materials C1 and C2. At this time, 10 parts by weight of raw material B1, 8 parts by weight of raw material B2 and 4 parts by weight of raw material C2 are heated at 80°C in 75 parts by weight of the first solvent and reacted for 5 hours. Next, 16 parts by weight of raw material C1 and 38 parts by weight of the first solvent are added, and the reaction is allowed to proceed for 6 hours while heating to 40°C. Thus, a polyamic acid solution having a resin solid content concentration of 25% by mass is obtained. Next, an orientation layer coating liquid is obtained from a polyamic acid solution having a resin solid content concentration of 25% by mass, a first solvent, and a second solvent. At this time, 12 parts by weight of a polyamic acid solution, 27 parts by weight of a first solvent, and 36 parts by weight of a second solvent are mixed and stirred for 24 hours while heating to 50°C.

[0126] Next, the first transparent electrode layer 34 was coated with the orientation coating liquid using a bar coater, and the coating was heated to 150° C. for 4 minutes. Thus, a first orientation layer 32 with a thickness of 100 nm and containing polyimide as the main component was obtained. Similarly, the second transparent electrode layer 35 was coated with the orientation coating liquid using a bar coater, and the coating was heated to 150° C. for 4 minutes. Thus, a second orientation layer 33 with a thickness of 100 nm and containing polyimide as the main component was obtained.

[0127] [Oriented coating liquid raw materials]

[0128] · B1: 4,4'-diaminodiphenylmethane (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0129] · B2: 3,5-diaminobenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0130] C1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0131] C2: 3-(Carboxymethyl)-1,2,4-cyclopentanetricarboxylic acid 1,4:2,3-dianhydride (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0132] First solvent: N-ethyl-2-pyrrolidone

[0133] Second solvent: Butyl cellosolve

[0134] [Dimming layer 31]

[0135] Next, the constituent materials and the formation method of the light-adjusting layer 31 are shown below. In addition, the constituent materials of the ionizing radiation curable composition of Test Examples 1 to 17 and the evaluation results of the light-adjusting sheet 11 are shown in Figure 3 and Figure 4 The dependence of the responsiveness of the dimming sheets 11 of Test Examples 1 to 13 in a low temperature environment on the first acrylic compound is shown in Figure 5 The dependency of the peel strength of the light-adjusting sheet 11 of Test Examples 1 to 13 on the first acrylic compound is shown in Figure 6 The dependence of the peel strength of the light-adjusting sheets 11 of Test Examples 1 to 9 on the acrylic compound mixing ratio is shown in Figure 7 The dependence of the haze of the light-adjusting sheets 11 of Test Examples 1 to 13 after the heat treatment on the first acrylic compound is shown in Figure 8 The dependence of the haze of the light-adjusting sheets 11 of Test Examples 1 to 9 after the heat treatment on the acrylic compound mixing ratio is shown in Fig. 9 The evaluation results of the dimming sheets 11 of Test Examples 1 to 13 are shown in the table below. Fig.10 middle.

[0136] First, a dimming coating liquid is generated using the following liquid crystal compound LCM, spacer SP, polymerization initiator, and ionizing radiation curable composition. The ionizing radiation curable composition is a mixture of compounds selected from the following compounds 1 to 9. At this time, as the dimming layer coating liquid of Test Examples 1 to 13, 48 parts by weight of the ionizing radiation curable composition are mixed with 50 parts by weight of the liquid crystal compound LCM, 1 part by weight of the polymerization initiator, and 1 part by weight of the spacer SP. As the dimming layer coating liquid of Test Examples 14 to 15, 47 parts by weight or more and 47.75 parts by weight or less of the ionizing radiation curable composition are mixed with 50 parts by weight of the liquid crystal compound LCM, 1 part by weight of the polymerization initiator, 0.25 parts by weight or more and 1 part by weight of the viscosity reducer, and 1 part by weight of the spacer SP.

[0137] Next, a light-adjusting coating liquid was applied on the first alignment layer 32 using a bar coater to form a light-adjusting coating layer, and a second alignment layer 33 was arranged on the light-adjusting coating layer to form a light-adjusting coating layer sandwiched by the first alignment layer 32 and the second alignment layer 33. Next, ultraviolet rays were irradiated from the first transparent support layer 36 to the light-adjusting coating layer, and ultraviolet rays were irradiated from the second transparent support layer 37 to the light-adjusting coating layer. Thus, a light-adjusting layer 31 with a thickness of 10 μm was obtained.

[0138] [Raw materials for light-adjusting coating liquid]

[0139] Liquid crystal compound LCM: fluorine-based nematic hybrid liquid crystal (product name: MLC-6608, refractive index anisotropy Δn=0.20 (manufactured by Merck))

[0140] · Spacer SP: PMMA spherical shape with a diameter of 10 μm (manufactured by Sekisui Chemicals Co., Ltd.)

[0141] Polymerization initiator: 1-hydroxycyclohexyl phenyl ketone (manufactured by IGM Resins BV)

[0142] ·Viscosity reducer: diisodecyl adipate (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0143] [Ionizing radiation curable composition]

[0144] Compound 1 is pentaerythritol tetrakis(3-mercaptobutyrate) (product name: Karenz MT PE-1 (manufactured by Showa Denko K.K.)). Compound 1 is a radical curing aid.

[0145] Compound 2 is a monofunctional acrylic compound, which is methoxy polyethylene glycol acrylate (product name: AM-130G (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.)). The double bond equivalent of compound 2 is 658 g / eq. Compound 2 contains a polyethylene oxide chain between the acrylate group and the methoxy group. The polyethylene oxide chain has ethylene oxide as a repeating unit. The number of repetitions of the polyethylene oxide chain of compound 2 is 13. Compound 2 is an example of a third acrylic compound.

[0146] Compound 3 is a monofunctional acrylic compound, and isobornyl acrylate (product name: IBXA (manufactured by Osaka Organic Chemical Industry Co., Ltd.)). The double bond equivalent of Compound 3 is 208 g / eq. Compound 3 is an example of the second acrylic compound.

[0147] Compound 4 is a bifunctional acrylic compound, which is ethoxy polyethylene glycol acrylate (product name: Lightacrylate 14EGA (manufactured by Kyoeisha Chemical Co., Ltd.)). The double bond equivalent of Compound 4 is 371 g / eq. Compound 4 is an example of a third acrylic compound containing a polyethylene oxide chain.

[0148] Compound 5 is a trifunctional acrylic compound, which is polyethylene oxide-modified trimethylolpropane triacrylate (product name: AT-20E (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.)). The double bond equivalent of Compound 5 is 392 g / eq. Compound 5 is an example of a third acrylic compound containing a polyethylene oxide chain.

[0149] Compound 6 is a trifunctional acrylic compound, and is trimethylolpropane triacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) The double bond equivalent of Compound 6 is 99 g / eq. Compound 6 is an example of the first acrylic compound.

[0150] Compound 7 is a tetrafunctional acrylic compound, pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) The double bond equivalent of Compound 7 is 88 g / eq. Compound 7 is an example of the first acrylic compound.

[0151] Compound 8 is a hexafunctional acrylic compound, and is a pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer (product name: 306I (manufactured by Kyoeisha Chemical Co., Ltd.)). The double bond equivalent of Compound 8 is 136 g / eq. Compound 8 is a urethane prepolymer of the first acrylic compound.

[0152] Compound 9 is a hexafunctional acrylic compound, and is dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) The double bond equivalent of Compound 9 is 96 g / eq. Compound 9 is an example of the first acrylic compound.

[0153] [Cooperate]

[0154] like Figure 3 As shown, the ionizing radiation curable composition of Test Example 1 is a mixture of 2 parts by weight of Compound 1 (free radical curing aid), 36 parts by weight of Compound 3 (second acrylic compound), 5 parts by weight of Compound 4 (third acrylic compound), and 5 parts by weight of Compound 7 (first acrylic compound). The content of the first acrylic compound in Test Example 1 is 10% by mass. The content of the polyethylene oxide chain in Test Example 1 is 9% by mass. The content of the second acrylic compound in Test Example 1 is 75% by mass. The content of the third acrylic compound in Test Example 1 is 10% by mass.

[0155] The ionizing radiation curable composition of Test Example 2 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 27 parts by weight of Compound 3 (second acrylic compound), 5 parts by weight of Compound 4 (third acrylic compound), and 14 parts by weight of Compound 7 (first acrylic compound). The content of the first acrylic compound in Test Example 2 is 29% by mass. The content of the polyethylene oxide chain in Test Example 2 is 9% by mass. The content of the second acrylic compound in Test Example 2 is 56% by mass. The content of the third acrylic compound in Test Example 2 is 10% by mass.

[0156] The ionizing radiation curable composition of Test Example 3 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 18 parts by weight of Compound 3 (second acrylic compound), 5 parts by weight of Compound 4 (third acrylic compound), and 23 parts by weight of Compound 7 (first acrylic compound). The content of the first acrylic compound in Test Example 3 is 48% by mass. The content of the polyethylene oxide chain in Test Example 3 is 9% by mass. The content of the second acrylic compound in Test Example 3 is 38% by mass. The content of the third acrylic compound in Test Example 3 is 10% by mass.

[0157] The ionizing radiation curable composition of Test Example 4 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 16 parts by weight of Compound 3 (second acrylic compound), 5 parts by weight of Compound 4 (third acrylic compound), and 25 parts by weight of Compound 7 (first acrylic compound). The content of the first acrylic compound in Test Example 4 is 52% by mass. The content of the polyethylene oxide chain in Test Example 4 is 9% by mass. The content of the second acrylic compound in Test Example 4 is 33% by mass. The content of the third acrylic compound in Test Example 4 is 10% by mass.

[0158] The ionizing radiation curable composition of Test Example 5 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 40 parts by weight of Compound 3 (second acrylic compound), 5 parts by weight of Compound 4 (third acrylic compound), and 1 part by weight of Compound 7 (first acrylic compound). The content of the first acrylic compound in Test Example 5 is 2% by mass. The content of the polyethylene oxide chain in Test Example 5 is 9% by mass. The content of the second acrylic compound in Test Example 5 is 83% by mass. The content of the third acrylic compound in Test Example 5 is 10% by mass.

[0159] The ionizing radiation curable composition of Test Example 6 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 38 parts by weight of Compound 3 (second acrylic compound), 5 parts by weight of Compound 4 (third acrylic compound), and 3 parts by weight of Compound 8 (first acrylic compound). The content of the first acrylic compound in Test Example 6 is 6% by mass. The content of the polyethylene oxide chain in Test Example 6 is 9% by mass. The content of the second acrylic compound in Test Example 6 is 79% by mass. The content of the third acrylic compound in Test Example 6 is 10% by mass.

[0160] The ionizing radiation curable composition of Test Example 7 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 3 parts by weight of Compound 2 (third acrylic compound), 36 parts by weight of Compound 3 (second acrylic compound), and 7 parts by weight of Compound 9 (first acrylic compound). The content of the first acrylic compound in Test Example 7 is 15% by mass. The content of the polyethylene oxide chain in Test Example 7 is 5% by mass. The content of the second acrylic compound in Test Example 7 is 75% by mass. The content of the third acrylic compound in Test Example 7 is 6% by mass.

[0161] The ionizing radiation curable composition of Test Example 8 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 28 parts by weight of Compound 3 (second acrylic compound), 8 parts by weight of Compound 5 (third acrylic compound), and 10 parts by weight of Compound 6 (first acrylic compound). The content of the first acrylic compound in Test Example 8 is 21% by mass. The content of the polyethylene oxide chain in Test Example 8 is 13% by mass. The content of the second acrylic compound in Test Example 8 is 58% by mass. The content of the third acrylic compound in Test Example 8 is 17% by mass.

[0162] The ionizing radiation curable composition of Test Example 9 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 36 parts by weight of Compound 3 (second acrylic compound), and 10 parts by weight of Compound 7 (first acrylic compound). The content of the first acrylic compound in Test Example 9 is 21% by mass. The content of the polyethylene oxide chain in Test Example 9 is 0% by mass. The content of the second acrylic compound in Test Example 9 is 75% by mass. The content of the third acrylic compound in Test Example 9 is 0% by mass.

[0163] like Figure 4 As shown, the ionizing radiation curable composition of Test Example 11 is a mixture of 2 parts by weight of Compound 1 (free radical curing aid), 43 parts by weight of Compound 3 (second acrylic compound), and 3 parts by weight of Compound 4 (third acrylic compound). The content of the first acrylic compound in Test Example 11 is 0% by mass. The content of the polyethylene oxide chain in Test Example 11 is 5% by mass. The content of the second acrylic compound in Test Example 11 is 90% by mass. The content of the third acrylic compound in Test Example 11 is 6% by mass.

[0164] The ionizing radiation curable composition of Test Example 12 is a mixture of 2 parts by weight of Compound 1 (free radical curing aid), 36 parts by weight of Compound 3 (second acrylic compound), and 10 parts by weight of Compound 4 (third acrylic compound). The content of the first acrylic compound in Test Example 12 is 0% by mass. The content of the polyethylene oxide chain in Test Example 12 is 16% by mass. The content of the second acrylic compound in Test Example 12 is 75% by mass. The content of the third acrylic compound in Test Example 12 is 21% by mass.

[0165] The ionizing radiation curable composition of Test Example 13 is a mixture of 2 parts by weight of Compound 1 (radical curing aid), 26 parts by weight of Compound 3 (second acrylic compound), and 20 parts by weight of Compound 4 (third acrylic compound). The content of the first acrylic compound in Test Example 13 is 0% by mass. The content of the polyethylene oxide chain in Test Example 13 is 31% by mass. The content of the second acrylic compound in Test Example 13 is 54% by mass. The content of the third acrylic compound in Test Example 13 is 42% by mass.

[0166] The ionizing radiation curable composition of Test Example 14 is a mixture of 2 parts by weight of compound 1 (free radical curing aid), 3 parts by weight of compound 2 (third acrylic compound), 35.75 parts by weight of compound 3 (second acrylic compound), and 7 parts by weight of compound 9 (first acrylic compound). The dimming coating liquid of Test Example 14 contains 0.25 parts by weight of a viscosity reducer in the dimming coating liquid. The content of the first acrylic compound in Test Example 14 is 15% by mass. The content of the polyethylene oxide chain in Test Example 14 is 5% by mass. The content of the second acrylic compound in Test Example 14 is 75% by mass. The content of the third acrylic compound in Test Example 14 is 6% by mass. The content of the viscosity reducer in Test Example 14 relative to the liquid crystal composition 31LC is 0.5% by mass.

[0167] The ionizing radiation curable composition of Test Example 15 is a mixture of 2 parts by weight of compound 1 (free radical curing aid), 3 parts by weight of compound 2 (third acrylic compound), 35.5 parts by weight of compound 3 (second acrylic compound), and 7 parts by weight of compound 9 (first acrylic compound). The dimming coating liquid of Test Example 15 contains 0.5 parts by weight of a viscosity reducer in the dimming coating liquid. The content of the first acrylic compound in Test Example 15 is 15% by mass. The content of the polyethylene oxide chain in Test Example 15 is 5% by mass. The content of the second acrylic compound in Test Example 15 is 75% by mass. The content of the third acrylic compound in Test Example 15 is 6% by mass. The content of the viscosity reducer in Test Example 15 relative to the liquid crystal composition 31LC is 1.0% by mass.

[0168] The ionizing radiation curable composition of Test Example 16 is a mixture of 2 parts by weight of compound 1 (free radical curing aid), 3 parts by weight of compound 2 (third acrylic compound), 35.25 parts by weight of compound 3 (second acrylic compound), and 7 parts by weight of compound 9 (first acrylic compound). The dimming coating liquid of Test Example 16 contains 0.75 parts by weight of a viscosity reducer in the dimming coating liquid. The content of the first acrylic compound in Test Example 16 is 15% by mass. The content of the polyethylene oxide chain in Test Example 16 is 5% by mass. The content of the second acrylic compound in Test Example 16 is 75% by mass. The content of the third acrylic compound in Test Example 16 is 6% by mass. The content of the viscosity reducer in Test Example 16 relative to the liquid crystal composition 31LC is 1.5% by mass.

[0169] The ionizing radiation curable composition of Test Example 17 is a mixture of 2 parts by weight of compound 1 (free radical curing aid), 3 parts by weight of compound 2 (third acrylic compound), 35.0 parts by weight of compound 3 (second acrylic compound), and 7 parts by weight of compound 9 (first acrylic compound). The dimming coating liquid of Test Example 17 contains 1 part by weight of a viscosity reducer. The content of the first acrylic compound in Test Example 17 is 15% by mass. The content of the polyethylene oxide chain in Test Example 17 is 5% by mass. The content of the second acrylic compound in Test Example 17 is 75% by mass. The content of the third acrylic compound in Test Example 17 is 6% by mass. The content of the viscosity reducer in Test Example 17 is 2.0% by mass relative to the liquid crystal composition 31LC.

[0170] [Evaluation method]

[0171] (i) Responsiveness evaluation

[0172] The dimming sheet 11 of each test example was arranged in a room temperature environment of 23°C, and a 100V AC signal was supplied to the dimming sheet 11 of each test example, and it was confirmed that the dimming sheet 11 of each test example changed from transparent to opaque. Next, the supply of the AC signal was stopped, and it was confirmed that the dimming sheet 11 changed from opaque to transparent. At this time, the haze was measured using a method based on JIS K 7136:2000, and the time from the stop of the supply of the AC signal to the haze of the dimming sheet 11 becoming stable was measured as the responsiveness under the room temperature environment.

[0173] The dimming sheet 11 of each test example was arranged in a low temperature environment of -23°C, and a 100V AC signal was supplied to the dimming sheet 11 of each test example, and it was confirmed that the dimming sheet 11 of each test example changed from transparent to opaque. Then, the supply of the AC signal was stopped, and it was confirmed that the dimming sheet 11 changed from opaque to transparent. At this time, similar to the responsiveness evaluation in a normal temperature environment, the time from the stop of the AC signal supply to the time when the haze of the dimming sheet 11 becomes stable was measured as the responsiveness in a low temperature environment.

[0174] (ii) Peel strength evaluation

[0175] A strip test piece with a width of 25 mm was cut out from the dimming sheet 11 of each test example, and the peel strength before the heat treatment at a tear angle of 180° was measured using a method based on JIS Z-0237: 2009. At this time, the first transparent support layer 36 of the test piece was fixed on the test plate, and the second transparent support layer 37 of the test piece was torn at 180° relative to the test plate.

[0176] (iii) Haze evaluation after heat treatment

[0177] The dimming sheet 11 of each test example was placed in an oven at 130° C. for 30 minutes to perform a heat treatment on the dimming sheet 11 of each test example. Next, a 100V AC signal was supplied to the dimming sheet 11 of each test example, and the haze of the transparent state after the heat treatment was measured.

[0178] [Evaluation results]

[0179] (i) Responsiveness

[0180] like Figure 3 As shown, in the dimming sheets 11 of Test Examples 1 to 9, a response time of 1 second was observed in a normal temperature environment. In the dimming sheets 11 of Test Examples 1 to 9, a response time of more than 1 second and less than 2 seconds was observed in a low temperature environment.

[0181] like Figure 4 As shown, in the dimming sheets 11 of test examples 11 to 13, a response time of 1 second can be seen under normal temperature. In the dimming sheets 11 of test examples 11 to 13, a response time of more than 8 seconds and less than 10 seconds can be seen under low temperature, which is significantly longer than the response time under normal temperature. In addition, in the dimming sheets 11 of test examples 14 to 17 to which a viscosity reducer is added, a response time of 1 second can be seen under normal temperature. In addition, in the dimming sheets 11 of test examples 14 to 17, a response time of 1 second can be seen under low temperature, which is equal to the response time under normal temperature.

[0182] Comparison between Test Example 5 and Test Examples 11 to 13 shows that the response time in a low temperature environment is shortened by satisfying the content of the first acrylic compound of 2% by mass or more, i.e., the lower limit of [Condition 1]. Comparison between Test Examples 1 to 5 and Test Examples 11 to 13 shows that the response time in a low temperature environment is substantially stable by satisfying the content of the first acrylic compound of 2% by mass or more and 52% by mass or less.

[0183] In addition, from the tendency of the response time of the dimming sheet 11 of Test Examples 11 to 13, it can be seen that a high content of the third acrylic compound will gradually shorten the response time in a low temperature environment. Among them, from the comparison between Test Example 5 and Test Examples 11 to 13, it can be seen that increasing the content of the first acrylic compound from 0 mass % to 2 mass % significantly shortens the response time in a low temperature environment compared to increasing the content of the third acrylic compound from 6 mass % to 42 mass %. From the effect brought about by the content of the first acrylic compound and the comparison between Test Examples 5 to 8 and Test Example 9, it can be seen that even if the content of the third acrylic compound is 0 mass %, by satisfying the lower limit value of [Condition 1], the response time in a low temperature environment will be shortened to approximately the same level as that in a room temperature environment.

[0184] like Figure 5As shown, the response time in a low temperature environment is drastically shortened by changing the content of the first acrylic compound from 0 mass % to 2 mass %. In addition, the response time in a low temperature environment is stabilized to be substantially the same as that in a room temperature environment when the content of the first acrylic compound is within a range of 2 mass % to 52 mass %. In this way, the dimming sheet 11 satisfies the lower limit of [Condition 1], and the cured product of the ionizing radiation curable composition becomes dense during the phase separation process of the dimming layer 31, while the low molecular weight compound can be suppressed from remaining in the liquid crystal composition 31LC. Moreover, the response time in a low temperature environment is shortened to be substantially the same as that in a room temperature environment.

[0185] (ii) Peel strength

[0186] return Figure 3 The dimming sheets 11 of Test Examples 1, 2, 5 to 8 had peel strengths of 0.20 N / 25 mm or more. The dimming sheets 11 of Test Examples 3 and 9 had peel strengths of 0.10 N or more. The dimming sheet 11 of Test Example 4 had a peel strength of less than 0.10 N / 25 mm.

[0187] like Figure 4 As shown, the peel strength of the dimming sheets 11 of Test Examples 11 and 12 was 0.10 N / 25 mm or more. The peel strength of the dimming sheet 11 of Test Example 13 was less than 0.10 N / 25 mm. In addition, the peel strength of the dimming sheets 11 of Test Examples 14 and 15 to which the viscosity reducer was added was 0.10 N / 25 mm or more. The peel strength of the dimming sheets 11 of Test Examples 16 and 17 was less than 0.10 N / 25 mm.

[0188] From the comparison between Test Example 3 and Test Example 4, it can be seen that reducing the content of the first acrylic compound from 52 mass % to 48 mass % can improve the peel strength to more than 0.10 N / 25 mm. From the comparison between Test Example 2 and Test Example 3, it can be seen that reducing the content of the first acrylic compound from 48 mass % to 29 mass % can dramatically improve the peel strength.

[0189] Comparison between Test Example 7 and Test Example 9 shows that the peel strength increases sharply when the content of the third acrylic compound increases to 5% by mass or more. In addition, comparison between Test Example 7 and Test Example 9 shows that the peel strength increases sharply when the content of the polyethylene oxide chain is 2% by mass or more and 20% by mass or less, that is, when [Condition 6] is satisfied.

[0190] Thus, from the comparison between Test Examples 1, 2, and 5 and Test Examples 3 and 4, and from the comparison between Test Examples 7 and 8 and Test Example 9, it can be seen that the peel strength is improved by satisfying the content of the first acrylic compound of 50% by mass or less and the content of the third acrylic compound of 5% by mass or more and 20% by mass or less. In addition, the peel strength is further improved by satisfying the content of the first acrylic compound of 40% by mass or less and the content of the third acrylic compound of 5% by mass or more and 20% by mass or less. Furthermore, the peel strength is further improved by satisfying the content of the first acrylic compound of 30% by mass or less and the content of the third acrylic compound of 5% by mass or more and 20% by mass or less.

[0191] That is, the peel strength is improved by the content of the first acrylic compound satisfying the upper limit of [Condition 1] and the content of the third acrylic compound satisfying [Condition 3]. At this time, from the evaluation results of Test Examples 1 to 3, 5, 7, and 8, it can be seen that the effectiveness of improving the peel strength is improved by satisfying the content of the second acrylic compound being 35% by mass or more and 85% by mass or less, that is, [Condition 2].

[0192] In addition, the peel strength is further improved by the content of the first acrylic compound satisfying the upper limit of [Condition 1A] and the content of the third acrylic compound satisfying [Condition 3]. At this time, from the evaluation results of Test Examples 1, 2, 5, 7, and 8, it can be seen that the effectiveness of improving the peel strength is improved by satisfying the content of the second acrylic compound being 45% by mass or more and 85% by mass or less, that is, [Condition 2A].

[0193] Furthermore, the peel strength is further improved by the content of the first acrylic compound satisfying the upper limit of [Condition 1B] and the content of the third acrylic compound satisfying [Condition 3]. At this time, from the evaluation results of Test Examples 1, 2, 5, 7, and 8, it can be seen that the effectiveness of improving the peel strength is improved by satisfying the content of the second acrylic compound of 55% by mass or more and 85% by mass or less, that is, [Condition 2B].

[0194] In addition, from the peel strength results of Test Examples 1, 2, 5, and 6, it can be seen that when the number of functional groups of the first acrylic compound is 3 or more and 5 or less, and the content of the first acrylic compound is 30% by mass or less, that is, [Condition 5], the effectiveness of obtaining a peel strength of 0.2N / 25mm or more is improved.

[0195] In addition, from the tendency of the peel strength of the dimming sheet 11 of Test Examples 11 to 13, it can be seen that making the content of the third acrylic compound higher than 20% by mass will reduce the peel strength. In addition, from the comparison of Test Example 7 and Test Example 14, it can be seen that reducing the content of the viscosity reducer to less than 0.25% by mass will sharply increase the peel strength. From the comparison of Test Example 7 and Test Example 14, it can be seen that making the content of the viscosity reducer 0.13% by mass or less can stabilize high peel strength. Not containing a viscosity reducer in the liquid crystal composition 31LC can further stabilize a higher peel strength. From the tendency of the peel strength of the dimming sheet 11 of Test Examples 14 to 17, it can be seen that increasing the content of the viscosity reducer from 0.25% by mass will further reduce the peel strength. In this way, when it is required to improve the peel strength, the viscosity reducer is preferably 0.50% by mass or less, more preferably 0.25% by mass or less, and it is further preferred that the viscosity reducer is not contained in the liquid crystal composition 31LC.

[0196] like Figure 6 As shown, when the content of the third acrylic compound satisfies the range of 5% by mass or more and 20% by mass or less, as the content of the first acrylic compound decreases from 50% by mass, the peel strength can be sharply improved. In addition, when the content of the first acrylic compound is within the range of 40% by mass or less, the peel strength can be stabilized at a high level of 0.2N / 25mm or more. In this way, the dimming sheet 11 satisfies [Condition 1] to [Condition 3] to suppress the densification of the cured product of the ionizing radiation curable composition from excessively increasing the rigidity, and the peel strength can be sharply increased to more than 0.10N / 25mm. Furthermore, the dimming sheet 11 satisfies [Condition 1A] [Condition 2A] [Condition 3] to stabilize the peel strength at a high level of 0.20N / 25mm or more.

[0197] like Figure 7 As shown in the figure, as the acrylic compound ratio increases from 0 to 0.25, the peel strength can be sharply increased. In addition, when the acrylic compound ratio is in the range of 0.25 or more, the peel strength can be stabilized at a high level of 0.20N / 25mm or more. In this way, the dimming sheet 11 satisfies [Condition 1] [Condition 2] [Condition 4] and can also suppress the densification of the cured product of the ionizing radiation curable composition and excessively increase the rigidity, and can stabilize the peel strength at a high level of 0.20N / 25mm or more.

[0198] (iii) Haze after heating treatment

[0199] Back to Figure 3 The dimming sheets 11 of Test Examples 1 to 9 had a low haze of 5% or less when transparent before the heat treatment.

[0200] The dimming sheets 11 of Test Examples 1 to 4 and 6 to 9 had a low haze of 10% or less when transparent after heat treatment. The dimming sheets 11 of Test Examples 3, 4, 8, and 9 had a lower haze of 6% or less when transparent after heat treatment. The dimming sheets 11 of Test Examples 1 to 4 and 6 to 9 had a low haze of 5% or less increased by heat treatment.

[0201] On the other hand, the dimming sheet 11 of Test Example 5 had a high haze of 14% when it was transparent after the heat treatment. The dimming sheet 11 of Test Example 5 had a haze increase of 9% after the heat treatment.

[0202] Back to Figure 4 , the dimming sheets 11 of test examples 11 to 13 have a low haze of less than 4% when transparent before the heat treatment. And the dimming sheets 11 of test examples 11 to 13 have a high haze of more than 11% when transparent after the heat treatment. The dimming sheets 11 of test examples 11 to 13 have a haze increase of more than 7% after the heat treatment. In addition, the dimming sheets 11 of test examples 14 to 17 have a low haze of less than 5% when transparent before the heat treatment. The dimming sheets 11 of test examples 14 to 17 have a low haze of more than 10% when transparent after the heat treatment.

[0203] Comparison between Test Example 6 and Test Examples 5 and 11 shows that increasing the content of the first acrylic compound from 0% by mass to 5% by mass or more can drastically suppress an increase in haze after heat treatment.

[0204] Comparison between Test Examples 1 to 4 and 6 and Test Example 5 shows that a content of the first acrylic compound of 5% by mass or more and 50% by mass or less can stably suppress an increase in haze after heat treatment.

[0205] At this time, the effectiveness of suppressing the increase of haze and improving the peel strength is improved by the content of the second acrylic compound being 30% by mass or more and 80% by mass or less. In addition, the content of the third acrylic compound is 5% by mass or more and 20% by mass or less. Furthermore, from the comparison between Test Examples 6 to 8 and Test Example 9, it can be seen that by satisfying the content of the polyethylene oxide chain being 2% by mass or more and 20% by mass or less, that is, [Condition 6], the peel strength can be improved to 0.11N / 25mm or more.

[0206] From the comparison of Test Examples 1 to 3 and 6 with Test Examples 4 and 5, it can be seen that the content of the first acrylic compound is 5% by mass or more and 40% by mass or less, which can suppress the increase of haze after heat treatment and improve the peel strength to 0.10N / 25mm or more. At this time, the effectiveness of suppressing the increase of haze and improving peel strength is improved by the content of the second acrylic compound being 40% by mass or more and 80% by mass or less. In addition, the content of the third acrylic compound is 5% by mass or more and 20% by mass or less. The content of the polyethylene oxide chain can be 2% by mass or more and 20% by mass or less.

[0207] From the comparison of Test Examples 1, 2, and 6 with Test Examples 3 to 5, it can be seen that the content of the first acrylic compound of 5% by mass or more and 30% by mass or less can suppress the increase in haze after heat treatment, while further improving the peel strength to 0.20N / 25mm or more. That is, by satisfying [Condition 5] that the number of functional groups of the first acrylic compound is 3 or more and 5 or less, and the content is 30% by mass or less, both the heat resistance and the peel strength of the dimming sheet 11 become very good. At this time, by the content of the second acrylic compound of 50% by mass or more and 80% by mass or less, the effectiveness of suppressing the increase in haze and improving the peel strength is further improved. In addition, the content of the third acrylic compound is 5% by mass or more and 20% by mass or less. The content of the polyethylene oxide chain can be 2% by mass or more and 20% by mass or less.

[0208] From the trend of the haze after the heat treatment of the dimming sheet 11 of Test Examples 11 to 13, it can be seen that the increase in the content of the third acrylic compound gradually reduces the haze after the heat treatment. Among them, from the comparison between Test Example 6 and Test Example 11, it can be seen that increasing the content of the first acrylic compound from 0 mass % to 6 mass % and increasing the content of the third acrylic compound from 6 mass % to 42 mass % effectively reduce the haze after the heat treatment to the same extent.

[0209] In addition, from the comparison between Test Example 7 and Test Examples 14 to 17, it can be seen that changing the content of the viscosity reducer within the range of 0 mass % to 1 mass % can suppress the increase in haze after heat treatment to the same extent. Furthermore, when the dimming sheet 11 requires improved responsiveness in a low temperature environment, improved peel strength, and low haze after heat treatment, the content of the viscosity reducer is preferably 0.50 mass % or less. In addition, when improved responsiveness in a low temperature environment, stabilization of high peel strength, and low haze after heat treatment are required, the content of the viscosity reducer is preferably less than 0.25 mass %, and more preferably less than 0.13 mass %.

[0210] In this case, if [Condition 1A] [Condition 2A] [Condition 3] is satisfied and the content of the first acrylic compound is 5% by mass or more, the reduction in peel strength due to the presence of the viscosity reducer can be suppressed. If [Condition 1B] [Condition 2B] [Condition 3] is satisfied and the content of the first acrylic compound is 5% by mass or more, the reduction in peel strength due to the presence of the viscosity reducer can be suppressed.

[0211] On the other hand, when [Condition 1] to [Condition 3] are satisfied but at least one of [Condition 1B] and [Condition 2B] is not satisfied, and stabilization of high peel strength is required, it is preferred that the liquid crystal composition 31LC does not contain a viscosity reducer. When [Condition 1], [Condition 2], [Condition 4] are satisfied but at least one of [Condition 1B] and [Condition 2B] is not satisfied, and stabilization of high peel strength is required, it is also preferred that the liquid crystal composition 31LC does not contain a viscosity reducer.

[0212] like Figure 8 As shown in FIG. 1 , by changing the content of the first acrylic compound from 0 mass % to 5 mass %, the increase in haze after the heat treatment can be rapidly suppressed. In addition, the change in haze relative to the change in the content of the first acrylic compound is gradually shifted by the content of the first acrylic compound being 5 mass % or more. Thus, the content of the first acrylic compound being 5 mass % or more can impart stable and good heat resistance to the dimming sheet 11.

[0213] like Fig. 9 As shown in FIG. 1 , as the acrylic compound ratio increases from 0 to 5, the haze after heat treatment is gradually increased from 5% to 14%. When the acrylic compound ratio is within the range of 0.25 to 2.0, the haze after heat treatment is stopped within the range of 5% to 9%. In this way, the dimming sheet 11 satisfies [Condition 1] [Condition 2] [Condition 4A] and shows good haze after heat treatment.

[0214] Fig.10 The white circle marks indicate that (i) the response in a low temperature environment is less than 2 seconds, (ii) the peel strength is greater than 0.2N / 25mm, and (iii) the haze after heat treatment is less than 9%. That is, Fig.10 The white circle marks indicate Test Examples 1, 2, and 6 to 8, which are levels at which good response and good peel strength are obtained in a low temperature environment, and good transparency can be obtained when heating is involved in production or installation.

[0215] Fig.10 The black triangle marks indicate that (i) the response under low temperature environment is less than 2 seconds, (ii) the peel strength is less than 0.2N / 25mm, and (iii) the haze after heat treatment is less than 9%. That is, Fig.10The black triangle marks indicate test examples 3, 4, and 9, which showed good responses in a low temperature environment and obtained good transparency when heating was involved in production or installation, but did not obtain a good level of peel strength.

[0216] Fig.10 The white square symbol indicates that (i) the response in a low temperature environment is less than 2 seconds, (ii) the peel strength is greater than 0.2N / 25mm, and (iii) the haze after heat treatment is greater than 10%. That is, Fig.10 The white square mark indicates Test Example 5, which obtained good response and good peel strength in a low temperature environment, but did not obtain a good transparency level when heating was involved in production or installation.

[0217] Fig.10 The black circle marks indicate that (i) the response in a low temperature environment is 10 seconds, (ii) the peel strength is 0.2N / 25mm or more, and (iii) the haze after heat treatment is 10% or more. Fig.10 The black circle symbol indicates Test Example 11, which obtained good peel strength, but did not obtain good response in a low temperature environment, and did not obtain a good transparency level during production or installation including heating.

[0218] Fig.10 The black diamond marks indicate that (i) the response under low temperature environment is 8 seconds or 9 seconds, (ii) the peel strength is less than 0.2N / 25mm, and (iii) the haze after heat treatment is above 10%. That is, Fig.10 The black diamond marks indicate Test Examples 12 and 13, where a good response was not obtained in a low temperature environment, a good peel strength was not obtained, and a good transparency level was not obtained during heating during production or installation.

[0219] like Fig.10 As shown, from the comparison between the white circular mark and the quadrilateral mark and the black circular mark and the diamond mark, it can be seen that the content of the first acrylic compound is 2% by mass or more, which can obtain good responsiveness in a low temperature environment. From the comparison between the white quadrilateral mark, the black circular mark and the diamond mark and the white circular mark, it can be seen that the content of the first acrylic compound is 5% by mass or more, which can obtain good responsiveness in a low temperature environment, and also obtain good haze when transparent after heat treatment. From the comparison between the black circular mark, the diamond mark and the triangle mark and the white circular mark and the quadrilateral mark, it can be seen that satisfying conditions 1A, 2A, 3 or satisfying conditions 1A, 2A, 3 can obtain good responsiveness and good peel strength in a low temperature environment.

[0220] [First alignment layer 32, second alignment layer 33, viscosity reducing agent]

[0221] The above-mentioned installation technology of the dimming film 11 requires heat resistance for the dimming film 11. The installation technology of the intermediate film method is to heat the glass substrate while sandwiching the dimming film 11 for pasting. The film sandwiching the dimming layer 31 will produce low molecular impurities from the film under the high temperature environment during pasting. Since the low molecular impurities diffused into the dimming layer 31 will deteriorate the electrical properties of the liquid crystal compound LCM, the surface treatment layer of the film sandwiching the dimming layer 31 has a barrier function to inhibit the contact between the low molecular impurities and the liquid crystal compound LCM.

[0222] The use of a flexible substrate such as the first transparent support layer 36 or the second transparent support layer 37 makes it possible to produce the dimming film 11 by roll-to-roll. However, the use of a substrate that is easily deformed in a high temperature environment will limit the formation conditions of the dimming film 11 to a low temperature environment to avoid a high temperature environment. When the orientation of the liquid crystal compound LCM is required during the supply stop of the voltage signal as in the reverse type dimming film 11, the dimming film 11 has a first orientation layer 32 or a second orientation layer 33. The first orientation layer 32 or the second orientation layer 33 that applies an orientation restriction force to the liquid crystal compound LCM is configured in a manner that contacts the dimming layer 31 regardless of the presence or absence of the above-mentioned surface treatment layer.

[0223] The formation conditions are limited to the first orientation layer 32 or the second orientation layer 33 under a low temperature environment containing unreacted substances such as polyamic acid or low molecular impurities such as residual solvents. The installation technology of the dimming sheet 11 that requires heating causes the byproducts or residual solvents generated by the unreacted substances to diffuse from the first orientation layer 32 or the second orientation layer 33 configured in a manner to contact the dimming layer 31 to the dimming layer 31. The low molecular impurities such as unreacted substances diffused to the dimming layer 31 reduce the effect of the orientation restriction force brought by the first orientation layer 32 or the second orientation layer 33 through the ionizing radiation curing resin layer 31P, which will increase the haze of the dimming sheet 11 when transparent. In this regard, in the process of phase separation between the cured product of the ionizing radiation curable composition and the liquid crystal composition 31LC, the structure that makes the cured product of the ionizing radiation curable composition dense includes a structure that inhibits the thermal diffusion of low molecular impurities through the ionizing radiation curing resin layer 31P to the liquid crystal composition 31LC.

[0224] The degree to which viscosity reducers such as adipic acid esters or phosphates increase viscosity due to a decrease in temperature is smaller than the degree to which viscosity of the liquid crystal compound LCM increases due to a decrease in temperature in a low temperature environment such as a cold place. The viscosity reducers in the liquid crystal composition 31LC reach the interface between the dimming layer 31 and other layers, which reduces the peel strength of the dimming layer 31 relative to other layers. In the process of phase separation between the cured product of the ionizing radiation curable composition and the liquid crystal composition 31LC, the cured product of the ionizing radiation curable composition is made dense, which can suppress the residue of low molecular weight compounds in the liquid crystal composition 31LC. Furthermore, the structure that makes the cured product of the ionizing radiation curable composition dense to the extent that low molecular weight compounds do not reduce the peel strength includes a structure that can suppress the diffusion of the viscosity reducer to the interface between the dimming layer 31 and other layers.

[0225] According to the above-described embodiment, the following effects can be obtained.

[0226] (1) The ionizing radiation curable resin layer 31P that satisfies conditions 1, 2, 3 or conditions 1, 2, 4 makes the cured product of the ionizing radiation curable composition dense during the phase separation process of the light-adjusting layer 31, and can suppress the low molecular weight compound from remaining in the liquid crystal composition 31LC. As a result, the ionizing radiation curable resin layer 31P can improve the responsiveness in a low temperature environment.

[0227] (2) The ionizing radiation-curable resin layer 31P satisfying conditions 1A, 2A, 3 or conditions 1A, 2A, 4 can inhibit low molecular weight compounds from reaching the liquid crystal compound LCM and improve the peel strength within the sheet of the dimming sheet 11 .

[0228] (3) The ionizing radiation-cured resin layer 31P satisfying conditions 1B, 2B, 3 or conditions 1B, 2B, 4 can inhibit low molecular weight compounds from reaching the liquid crystal compound LCM and can significantly improve the peel strength within the dimming sheet 11 .

[0229] (4) The content of the first acrylic compound may be 5% to 50% by mass, the content of the second acrylic compound may be 30% to 80% by mass, and the content of the third acrylic compound may be 5% to 20% by mass. Thus, the ionizing radiation curable resin layer 31P suppresses low molecular weight impurities contained in the first alignment layer 32 or the second alignment layer 33 from reaching the liquid crystal compound LCM. As a result, the heat resistance of the optical characteristics of the dimming sheet 11 is improved.

[0230] (5) The content of the first acrylic compound may be 5% by mass or more and 40% by mass or less, the content of the second acrylic compound may be 40% by mass or more and 80% by mass or less, and the content of the third acrylic compound may be 5% by mass or more and 20% by mass or less. In addition, the acrylic compound ratio may be 0.25 or more and 2.0 or less. Thus, in addition to the effect based on (1) above, the ionizing radiation curing resin layer 31P can also improve the heat resistance of the optical characteristics of the dimming sheet 11, and at the same time, can also improve the peel strength within the sheet of the dimming sheet 11.

[0231] (6) The content of the first acrylic compound may be 5% to 30% by mass, the content of the second acrylic compound may be 50% to 80% by mass, and the content of the third acrylic compound may be 5% to 20% by mass. In addition, the acrylic compound ratio may be 0.25 to 2.0. Thus, in addition to the effect based on (2) above, the ionizing radiation curing resin layer 31P can also improve the heat resistance of the optical characteristics of the dimming sheet 11, and can also greatly improve the peel strength within the sheet of the dimming sheet 11.

[0232] (7) In addition to the above (4) to (6), when the light modulating sheet 11 includes the first alignment layer 32 and the second alignment layer 33, it is possible to provide a reverse type light modulating sheet 11 with improved responsiveness in a low temperature environment.

[0233] (8) The ionizing radiation-curable resin layer 31P may also satisfy conditions 1A, 2A, 3 or conditions 1A, 2A, 4, and the liquid crystal composition 31LC may contain a viscosity reducer in an amount of 0.25 mass % or less. Thus, the dimming sheet 11 can suppress a decrease in peel strength while improving the effectiveness of the responsiveness in a low temperature environment.

[0234] (9) The ionizing radiation curable resin layer 31P may also satisfy conditions 1B, 2B, 3 or conditions 1B, 2B, 4, and the liquid crystal composition 31LC may not contain a viscosity reducing agent. Thus, the dimming sheet 11 can significantly suppress the reduction in peel strength while improving the effectiveness of the responsiveness in a low temperature environment.

[0235] Explanation of symbols

[0236] LCM Liquid Crystal Compounds

[0237] 10Dimming device

[0238] 11 dimmer

[0239] 12. Drive unit

[0240] 31 dimming layers

[0241] 31P ionizing radiation curing resin layer

[0242] 31LC Liquid Crystal Composition

[0243] 31D Gap

[0244] 32First orientation layer

[0245] 33 Second orientation layer

[0246] 34 first transparent electrode layer

[0247] 35 second transparent electrode layer

[0248] 36 first transparent support layer

[0249] 37 second transparent support layer

Claims

1. A dimming film, characterized in that: The device comprises a first transparent electrode layer, a second transparent electrode layer, and a dimming layer located between the first transparent electrode layer and the second transparent electrode layer. The haze of the light-adjusting layer is changed by changing the voltage applied between the first transparent electrode layer and the second transparent electrode layer. The dimming layer includes an ionizing radiation curable resin layer dividing gaps and a liquid crystal composition filled in the gaps. Acryloyl and methacryloyl are functional groups. Among the acrylic compounds constituting the ionizing radiation curable resin layer, an acrylic compound having three or more functional groups and a double bond equivalent of 150 g / eq or less is a first acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more of the ionizing radiation curable resin layer.

2. The dimming film according to claim 1, characterized in that: The acrylic compound constituting the ionizing radiation curable resin layer has one or more and three or less functional groups and polyethylene oxide chains and has a double bond equivalent of 300 g / eq or more and 700 g / eq or less as a third acrylic compound. The content of the third acrylic compound constituting the ionizing radiation curable resin layer is 5% by mass or more and 20% by mass or less of the ionizing radiation curable resin layer.

3. The dimming film according to claim 2, characterized in that: The light modulating sheet includes a first alignment layer sandwiched between the first transparent electrode layer and the light modulating layer, and a second alignment layer sandwiched between the second transparent electrode layer and the light modulating layer. A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 5% by mass or more and 40% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 55% by mass or more and 80% by mass or less of the ionizing radiation curable resin layer.

4. The dimming film according to claim 2, characterized in that: A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more and 50% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 35% by mass or more and 85% by mass or less of the ionizing radiation curable resin layer.

5. The dimming film according to claim 1, characterized in that: A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The acrylic compound constituting the ionizing radiation curable resin layer has one or more and three or less functional groups and polyethylene oxide chains and has a double bond equivalent of 300 g / eq or more and 700 g / eq or less as a third acrylic compound. The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more and 50% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 35% by mass or more and 85% by mass or less of the ionizing radiation curable resin layer. The content of the third acrylic compound constituting the ionizing radiation curable resin layer is 0.25 or more relative to the content of the first acrylic compound constituting the ionizing radiation curable resin layer.

6. The dimming sheet according to any one of claims 3 to 5, wherein: The number of the functional groups in the first acrylic compound is 3 or more and 5 or less, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 30% by mass or less of the ionizing radiation curable resin layer.

7. The dimming sheet according to claim 3, wherein: The first alignment layer and the second alignment layer each include at least one polymer selected from a polyimide precursor and a polyimide.

8. The dimming sheet according to claim 4 or 5, wherein: The liquid crystal composition does not contain a viscosity reducing agent.

9. The dimming sheet according to any one of claims 3 to 5, wherein: The first acrylic compound is a pentaerythritol compound, The second acrylic compound is isobornyl acrylate, The third acrylic compound is an alkoxy polyethylene glycol compound.

10. The dimming sheet according to any one of claims 3 to 5, wherein: The first acrylic compound is a trimethylolpropane compound, The second acrylic compound is isobornyl acrylate, The third acrylic compound is a polyethylene oxide-modified trimethylolpropane compound.

11. The dimming sheet according to any one of claims 3 to 5, wherein: The weight of the liquid crystal composition is 20% by mass or more and 70% by mass or less relative to the sum of the weight of the ionizing radiation curable resin layer and the weight of the liquid crystal composition.

12. A dimming device, characterized in that: It includes a dimming plate and a driving unit for applying voltage to the dimming plate. The dimming film comprises a first transparent electrode layer, a second transparent electrode layer, and a dimming layer located between the first transparent electrode layer and the second transparent electrode layer. The haze of the light-adjusting layer is changed by changing the voltage applied between the first transparent electrode layer and the second transparent electrode layer. The light-adjusting layer includes an ionizing radiation-curable resin layer defining gaps and a liquid crystal composition filled in the gaps. Acryloyl and methacryloyl are functional groups. Among the acrylic compounds constituting the ionizing radiation curable resin layer, an acrylic compound having three or more functional groups and a double bond equivalent of 150 g / eq or less is a first acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more of the ionizing radiation curable resin layer.

13. The dimming device according to claim 12, characterized in that: The acrylic compound constituting the ionizing radiation curable resin layer has one or more and three or less functional groups and polyethylene oxide chains and has a double bond equivalent of 300 g / eq or more and 700 g / eq or less as a third acrylic compound. The content of the third acrylic compound constituting the ionizing radiation curable resin layer is 5% by mass or more and 20% by mass or less of the ionizing radiation curable resin layer.

14. The dimming device according to claim 13, characterized in that: The light modulating sheet includes a first alignment layer sandwiched between the first transparent electrode layer and the light modulating layer, and a second alignment layer sandwiched between the second transparent electrode layer and the light modulating layer. A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 5% by mass or more and 40% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 55% by mass or more and 80% by mass or less of the ionizing radiation curable resin layer.

15. The dimming device according to claim 13, characterized in that: A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more and 50% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 35% by mass or more and 85% by mass or less of the ionizing radiation curable resin layer.

16. The dimming device according to claim 12, characterized in that: A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The acrylic compound constituting the ionizing radiation curable resin layer has one or more and three or less functional groups and polyethylene oxide chains and has a double bond equivalent of 300 g / eq or more and 700 g / eq or less as a third acrylic compound. The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more and 50% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 35% by mass or more and 85% by mass or less of the ionizing radiation curable resin layer. The content of the third acrylic compound constituting the ionizing radiation curable resin layer is 0.25 or more relative to the content of the first acrylic compound constituting the ionizing radiation curable resin layer.

17. A method for manufacturing a dimming film, characterized in that: It contains: forming a coating layer containing an ionizing radiation curable composition and a liquid crystal composition between the first transparent electrode layer and the second transparent electrode layer; and a step of forming a light-adjusting layer between the first transparent electrode layer and the second transparent electrode layer by irradiating the coating layer with ionizing radiation, wherein the light-adjusting layer includes an ionizing radiation-curable resin layer defining gaps and the liquid crystal composition filled in the gaps; The haze of the light-adjusting layer is changed by changing the voltage applied between the first transparent electrode layer and the second transparent electrode layer. Among them, acryloyl and methacryloyl are functional groups. Among the acrylic compounds constituting the ionizing radiation curable resin layer, an acrylic compound having three or more functional groups and a double bond equivalent of 150 g / eq or less is a first acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more of the ionizing radiation curable resin layer.

18. The method for manufacturing a dimming sheet according to claim 17, characterized in that: The acrylic compound constituting the ionizing radiation curable resin layer has one or more and three or less functional groups and polyethylene oxide chains and has a double bond equivalent of 300 g / eq or more and 700 g / eq or less as a third acrylic compound. The content of the third acrylic compound constituting the ionizing radiation curable resin layer is 5% by mass or more and 20% by mass or less of the ionizing radiation curable resin layer.

19. The method for manufacturing a dimming sheet according to claim 18, characterized in that: The light modulating sheet includes a first alignment layer sandwiched between the first transparent electrode layer and the light modulating layer, and a second alignment layer sandwiched between the second transparent electrode layer and the light modulating layer. A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 5% by mass or more and 40% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 55% by mass or more and 80% by mass or less of the ionizing radiation curable resin layer.

20. The method for manufacturing a dimming sheet according to claim 18, characterized in that: A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more and 50% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 35% by mass or more and 85% by mass or less of the ionizing radiation curable resin layer.

21. The method for manufacturing a dimming sheet according to claim 17, characterized in that: A monofunctional alkyl acrylate containing a saturated alkyl group having 2 to 12 carbon atoms, a monofunctional alkoxyalkyl acrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms, a monofunctional alkyl methacrylate containing a saturated alkyl group having 2 to 12 carbon atoms, and a monofunctional alkoxyalkyl methacrylate containing a saturated alkoxyalkyl group having 2 to 12 carbon atoms are the second acrylic compound, The acrylic compound constituting the ionizing radiation curable resin layer has one or more and three or less functional groups and polyethylene oxide chains and has a double bond equivalent of 300 g / eq or more and 700 g / eq or less as a third acrylic compound. The content of the first acrylic compound constituting the ionizing radiation curable resin layer is 2% by mass or more and 50% by mass or less of the ionizing radiation curable resin layer. The content of the second acrylic compound constituting the ionizing radiation curable resin layer is 35% by mass or more and 85% by mass or less of the ionizing radiation curable resin layer. The content of the third acrylic compound constituting the ionizing radiation curable resin layer is 0.25 or more relative to the content of the first acrylic compound constituting the ionizing radiation curable resin layer.

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