Liquid crystal dimming element

Abstract

The objective is to provide a liquid crystal dimming element that can achieve both anti-glare and heat-suppressing functions. [Solution] The liquid crystal dimming element of this embodiment comprises a pair of transparent electrode substrates having a transparent electrode layer, and a dimming layer disposed inside the transparent electrode substrates and containing liquid crystal molecules, wherein the dimming layer contains a dichroic dye, the visible light transmittance of the transparent electrode substrates is 89% or less, and the visible light reflectance of the transparent electrode substrates is 6.5% or more.

Description

[Technical Field]

[0001] This invention relates to a liquid crystal dimming element. [Background technology]

[0002] Patent Document 1 discloses an invention relating to a light-adjustable film equipped with a polymer-dispersed liquid crystal layer. The transparent conductive layer includes a light-transmitting resin and anisotropic conductive fibers. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-60521 [Overview of the project] [Problems that the invention aims to solve]

[0004] A technology that simultaneously addresses both glare prevention from sunlight and heat generation caused by sunlight has not yet been established. This invention has been made in view of the above, and aims to provide a liquid crystal dimming element that can achieve both anti-glare function and heat suppression function. [Means for solving the problem]

[0005] The liquid crystal dimming element of this embodiment comprises a pair of transparent electrode substrates having a transparent electrode layer, and a dimming layer disposed inside the transparent electrode substrates and containing liquid crystal molecules, wherein the dimming layer contains a dichroic dye, the visible light transmittance of the transparent electrode substrates is 89% or less, and the visible light reflectance of the transparent electrode substrates is 6.5% or more.

[0006] Alternatively, the liquid crystal dimming element of this embodiment comprises a pair of transparent electrode substrates having a transparent electrode layer, and a dimming layer disposed inside the transparent electrode substrates and containing liquid crystal molecules, wherein the dimming layer contains a dichroic dye, and the transparent electrode substrates contain silver or a silver alloy.

[0007] Alternatively, the liquid crystal dimming element of this embodiment is a liquid crystal dimming element comprising a pair of transparent electrode substrates having a transparent electrode layer, and a dimming layer disposed inside the transparent electrode substrates and containing liquid crystal molecules, wherein the dimming layer contains a dichroic dye, and the visible light transmittance of the liquid crystal dimming element when light is blocked is 4% or less. [Effects of the Invention]

[0008] According to the present invention, by including a dichroic dye in the photochromic layer, controlling the visible light transmittance and visible light reflectance of the transparent electrode substrate, and including silver or a silver alloy in the transparent electrode layer, it is possible to simultaneously solve the problems of preventing glare from sunlight and preventing heat generation caused by sunlight. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view of the liquid crystal dimming element of this embodiment. [Modes for carrying out the invention]

[0010] The embodiments of the present invention will be described in detail below, but the following description is merely an example (representative example) of the embodiments described herein, and the present invention is not limited to these contents unless it exceeds the gist of the invention. Also, the notation "~" includes lower and upper limits.

[0011] <Configuration of the liquid crystal dimming element 10> Figure 1 is a schematic cross-sectional view of the liquid crystal dimming element 10 of this embodiment. As shown in Figure 1, the liquid crystal dimming element 10 has a laminated structure comprising a pair of transparent substrates 1, a transparent electrode layer 2 formed on the inside of each transparent substrate 1, and a dimming layer 3 formed on the inside of each transparent electrode layer 2. "Inside" refers to the opposing sides.

[0012] In other words, the liquid crystal dimming element 10 is stacked from bottom to top in the following order: transparent substrate 1 (first transparent substrate), transparent electrode layer 2 (first transparent electrode layer), dimming layer 3, transparent electrode layer 2 (second transparent electrode layer), and transparent substrate (second transparent substrate) 1.

[0013] (Transparent electrode substrate 4) The transparent electrode substrate 4 is composed of the transparent base material 1 and the transparent electrode layer 2 shown in FIG. 1. The transparent electrode substrate 4 is in the form of a film. The "film" refers to a planar shape in which the width and length of the plane are extremely large compared to the thickness, but it can also be read as "sheet". In this embodiment, the "film" and "sheet" are not distinguished by the thickness defined in the JIS standard.

[0014] Although the material of the transparent base material 1 is not limited, a PET (Polyethylene Terephthalate) film is preferably used. In addition, the transparent electrode layer 2 is a transparent conductive layer utilizing the conductivity of a metal and contains silver (Ag) or a silver alloy.

[0015] Although not limiting the film thickness, the transparent base material 1 is about 50 μm to 200 μm, and the transparent electrode layer 2 is about 10 μm to 100 μm.

[0016] Further, a functional layer may be provided on at least either one of the interface between the transparent base material 1 and the transparent electrode layer 2 or the outer surface of the transparent base material 1 (the surface located on the opposite side to the side facing the transparent electrode layer 2). The functional layer preferably includes at least one of, for example, a hard coat layer, an anti-blocking layer, a primer layer, a protective layer, or an index matching layer.

[0017] (Dimming layer 3) The dimming layer 3 contains a liquid crystal composition. The dimming layer 3 is assumed to be composed of, for example, polymer dispersed liquid crystal (PDLC: Polymer Dispersed Liquid Crystal), but may be composed of polymer network liquid crystal (PNLC: Polymer Network Liquid Crystal), capsule-type nematic liquid crystal (NCAP: Nematic Curvilinear Aligned Phase), or the like. For example, polymer dispersed liquid crystal and polymer network liquid crystal have a three-dimensional network-shaped polymer network and hold liquid crystal molecules in the voids of the polymer network. The liquid crystal molecules contained in the dimming layer 3 have, for example, a positive dielectric anisotropy, and the dielectric constant in the long axis direction of the liquid crystal molecules is larger than the dielectric constant in the short axis direction of the liquid crystal molecules. The liquid crystal molecules are, for example, Schiff base type, azo type, azoxy type, biphenyl type, terphenyl type, benzoic acid ester type, trans type, pyrimidine type, cyclohexanecarboxylic acid ester type, phenylcyclohexane type, dioxane type liquid crystal molecules.

[0018] The dimming layer 3 of the present embodiment contains a dichroic dye. In the present embodiment, the color tone in the light-shielding state (opaque state) can be made black (so-called black dimming), and thus scattered light can be absorbed and whitening due to scattered light can be suppressed. For example, a dimming device (dimming sheet, dimming film) with a wide viewing angle suitable for an in-vehicle space or a living space can be realized.

[0019] Also, in the present embodiment, it is preferable that the dimming layer 3 contains black spacers (black functional fine particles). Thereby, a high function (due to the synergistic effect of the dichroic dye and the black spacer) can be achieved in combination with the dichroic dye contained in the dimming layer 3. More specifically, inside the dimming layer, scattered light is absorbed by the dichroic dye and the black spacers, so that high light-shielding properties in the opaque state can be realized.

[0020] <The background of the liquid crystal dimming element 10 of the present embodiment> As described above, a dimming device using a dimming layer made of a liquid crystal composition containing a dichroic dye can achieve high light-shielding properties in an opaque state and can be applied to windows of structures for purposes such as protecting privacy and controlling the ingress of energy into buildings.

[0021] In recent years, these dimming devices have been considered for outdoor use in structures and for applications in automobile windows and sunroofs. Such applications require measures to prevent glare from sunlight and to mitigate heat generation caused by sunlight.

[0022] In addressing glare from sunlight, it is necessary to reduce the total light transmittance of the light-adjusting layer when it is shading. For this purpose, for example, laminating smoked glass onto a light-adjusting film has been considered. However, smoked glass raises concerns about heat absorption by the glass itself and the resulting thermal cracking. Furthermore, since measures to counter heat generated by sunlight are also required, simply laminating smoked glass makes it difficult to simultaneously solve both the problem of glare from sunlight and the problem of heat generated by sunlight.

[0023] Thus, dimming technology that simultaneously addresses both glare prevention from sunlight and heat generation caused by sunlight has not yet been established, which has been a major obstacle to practical application.

[0024] Therefore, as a result of diligent research, the inventors have invented a liquid crystal dimming element that can simultaneously establish anti-glare and heat-suppressing functions by including a dichroic dye in the dimming layer, controlling the visible light transmittance and visible light reflectance of the transparent electrode substrate, and including silver or a silver alloy in the transparent electrode layer.

[0025] <Features of the liquid crystal dimming element 10 in this embodiment> The liquid crystal dimming element 10 of this embodiment is characterized by containing a dichroic dye in the dimming layer, adjusting the visible light transmittance and visible light reflectance of the transparent electrode substrate, and containing silver or a silver alloy in the transparent electrode layer.

[0026] According to this embodiment, in addition to the light absorption by the dichroic dye contained in the light-adjusting layer, the light absorption and reflection effects of the transparent electrode substrate are added, making it possible to lower the transmittance of the liquid crystal light-adjusting element to a lower value than expected when light is blocked.

[0027] "Lower than expected" means that, when compared to a case where ITO is used for the transparent electrode layer, the result obtained is lower than the expected value.

[0028] That is, if the visible light transmittance of the transparent electrode substrate in this embodiment is A, and the visible light transmittance of the transparent electrode substrate in the comparative example (using ITO for the transparent electrode layer) is B, then the transmittance ratio of the liquid crystal dimming element in this embodiment to the comparative example is (A 2 / B 2 ) is assumed, but in reality, the transmittance ratio in this embodiment is the assumed value (A 2 / B 2 It was found to be below ). The reason why A and B were squared to obtain the transmittances of this embodiment and the comparative example is that, as shown in Figure 1, a pair of transparent electrode substrates 4 are provided. Let's consider the reasons why the results fell below expectations.

[0029] When light is blocked, the light-adjusting layer scatters light, and the dichroic dye contained in the light-adjusting layer absorbs the scattered light. At this time, scattered light that is not absorbed by the dichroic dye is incident on the transparent electrode substrate on the light-emitting side at various angles, but incident light exceeding the total reflection angle is reflected off the surface of the transparent electrode substrate on the light-emitting side and returned to the light-adjusting layer, where it is absorbed by the dichroic dye. This reflection characteristic can be made greater than in the comparative example using ITO. Also, light absorption at the transparent electrode substrate can be made higher compared to the comparative example using ITO. As a result, the transmittance ratio of the liquid crystal light-adjusting element of this embodiment compared to the comparative example can be set to the assumed value (A 2 / B 2 It is thought that this can be made smaller.

[0030] In this embodiment, the light absorption of the dichroic dye and the light absorption and reflection effects of the transparent electrode substrate simultaneously solve the problems of preventing glare from sunlight and preventing heat generation caused by sunlight.

[0031] In this embodiment, the visible light transmittance of the transparent electrode substrate is 89% or less, and the visible light reflectance of the transparent electrode substrate is 6.5% or more. As a result, the visible light transmittance of the transparent electrode substrate can be reduced and the visible light reflectance of the transparent electrode substrate can be increased compared to the comparative example using ITO. Accordingly, the transmittance ratio of the liquid crystal dimming element in this embodiment to the comparative example is set to the assumed value (A 2 / B 2 It can be made smaller and achieve both anti-glare and heat-suppressing functions.

[0032] Visible light transmittance is determined, for example, by measuring transmittance in the visible light region using a UH-4150 (manufactured by Hitachi High-Tech) within the measurement wavelength range of 380 nm to 1550 nm, and then determining the average transmittance in that region.

[0033] Furthermore, the visible light reflectance can be measured by a method compliant with JIS R3106:2019. Light is shone onto the surface of the transparent electrode substrate 4 at an incident angle of 90°. The visible light reflectance can then be measured based on the specular reflection of the incident light. The visible light reflectance is calculated in accordance with JIS R3106:2019 by irradiating the substrate with light containing wavelengths from 380 nm to 780 nm and using spectral data acquired at 10 nm intervals from 380 nm to 780 nm.

[0034] In this embodiment, the visible light transmittance of the transparent electrode substrate 4 is preferably 88% or less, more preferably 87% or less, and even more preferably 86% or less.

[0035] Furthermore, the visible light transmittance of the transparent electrode substrate 4 is preferably 30% or more, preferably 40% or more, more preferably 45% or more, even more preferably 50% or more, even more preferably 55% or more, even more preferably 60% or more, and most preferably 70% or more.

[0036] Furthermore, the visible light reflectance of the transparent electrode substrate 4 is preferably 6.6% or higher, more preferably 6.7% or higher, and even more preferably 6.8% or higher.

[0037] Furthermore, the visible light reflectance of the transparent electrode substrate 4 can be set to 15% or less, 13% or less, 10% or less, 9% or less, or 8% or less, taking into account the balance with the visible light transmittance. As a result, the visible light transmittance of the transparent electrode substrate can be reduced more effectively than in the comparative example using ITO, while the visible light reflectance of the transparent electrode substrate can be increased.

[0038] In this embodiment, measurement errors in visible light transmittance and visible light reflectance are permitted. Since the film thickness of the transparent electrode substrate 4 is quite thin, a reflectance range of approximately ±1% can be allowed.

[0039] Furthermore, in this embodiment, the transparent electrode layer is characterized by containing silver (Ag) or an Ag alloy. Although not limited thereto, the transparent electrode layer may be, for example, a metal mesh formed by forming Ag wires in a matrix on a transparent substrate, a transparent conductive film obtained by coating or printing an ink composition in which Ag particles or Ag wires are mixed in ink onto a transparent substrate, or an Ag thin film substrate uniformly formed on the surface of a transparent substrate by sputtering or vapor deposition of an Ag thin film.

[0040] In this way, by forming a metal layer containing silver or a silver alloy as the transparent electrode layer, transparency and good conductivity can be ensured, and the light absorption and reflection effects of the transparent electrode substrate can be enhanced compared to when ITO is used. As a result, both measures to prevent glare from sunlight and measures to prevent heat generation from sunlight can be solved simultaneously.

[0041] In a transparent electrode substrate equipped with a transparent electrode layer containing silver or a silver alloy, the visible light transmittance of the transparent electrode substrate can be precisely reduced to 89% or less, and the visible light reflectance of the transparent electrode substrate can be reduced to 6.5% or more.

[0042] Furthermore, this embodiment is characterized in that the visible light transmittance of the liquid crystal dimming element when light is blocked is 4% or less. As a result, the visible light transmittance can be reduced compared to when ITO is used for the transparent electrode layer, and excellent light-blocking properties can be achieved. In this embodiment, the visible light transmittance of the liquid crystal dimming element when light is blocked is preferably 3.7% or less, and more preferably 3.5% or less.

[0043] Furthermore, while a lower visible light transmittance of the liquid crystal dimming element when light is blocked is desirable, it is actually difficult to achieve 0%. Therefore, if we were to indicate a lower limit, it could be 0.1% or higher, 0.5% or higher, 1.0% or higher, 1.5% or higher, and 2.0% or higher.

[0044] In this embodiment, the visible light transmittance of the transparent electrode substrate is 89% or less, the visible light reflectance of the transparent electrode substrate is 6.5% or more, and by using silver or a silver alloy in the transparent electrode layer, the visible light transmittance of the liquid crystal dimming element when light is blocked can be precisely adjusted to 4% or less.

[0045] Furthermore, in this embodiment, it is preferable that the transmittance of the liquid crystal dimming element at a wavelength of 850 nm is 60% or less when light is blocked, and the transmittance at a wavelength of 1550 nm is 50% or less. In this embodiment, compared to the case where ITO is used for the transparent electrode layer, the transmittance in the near-infrared and infrared regions can be significantly reduced, and a high heat shielding effect can be obtained.

[0046] In this embodiment, the transmittance at a wavelength of 850 nm is more preferably 50% or less, even more preferably 45% or less, and even more preferably 40% or less. While not limiting the lower limit, the transmittance at 850 nm can be 5% or more, 10% or more, 15% or more, 20% or more, 25% or more, and 30% or more. Furthermore, the transmittance at a wavelength of 1550 nm is more preferably 40% or less, even more preferably 30% or less, even more preferably 20% or less, and even more preferably 15% or less. While not limiting the lower limit, the transmittance at 1550 nm can be 1% or more, 3% or more, 5% or more, 7% or more, and even more preferably 10% or more. In this embodiment, compared to the case where ITO is used for the transparent electrode layer, the transmittance at 850 nm and the transmittance at 1550 nm can be reduced by 10% or more, preferably 15% or more, and more preferably 20% or more.

[0047] According to the liquid crystal dimming element and the device using the same of this embodiment, for example, there is no need to laminate smoked glass as a measure against glare from sunlight, and both glare from sunlight and heat generation from sunlight can be solved simultaneously, so it can be preferably applied to outdoor applications of structures, as well as to automobile windows and sunroofs. [Examples]

[0048] The present invention will be described in detail below with reference to examples taken to clarify its effects. However, the present invention is not limited in any way by the following examples.

[0049] <Regarding the material composition of the light-adjusting layer> First, let's explain the material composition used in the light-adjusting layer. Liquid crystal A, shown in Table 1, is a composition mainly composed of cyano-based liquid crystal compounds and fluorine-based liquid crystal compounds, and is a nematic liquid crystal composition with positive dielectric anisotropy (Δε>0).

[0050] In addition, dichroic dyes were azo-based and anthraquinone-based black mixed dyes (three-color mixing of YMC), and the addition amount was 2.5% by mass (wt%).

[0051] In addition, the monomer composition B shown in Table 1 is a monomer composition obtained by appropriately mixing monomers such as polyfunctional acrylate / methacrylate, monofunctional acrylate, and urethane acrylate. The liquid crystal ratio shown in Table 1 indicates the mixing ratio of liquid crystal A and monomer composition B.

[0052]

Table 1

[0053] <Regarding the transparent electrode substrate> In Examples 1 to 3, a transparent electrode substrate obtained by sputtering an Ag thin film uniformly on the surface of a PET substrate was used. In addition, in the comparative example, a transparent electrode substrate having an ITO film uniformly formed on the surface of a PET substrate was used.

[0054] In Examples 1 and 3 and the comparative example, a PET film was used as the transparent substrate. On the other hand, in Example 2, polycarbonate (PC) was used as the transparent substrate. The surface resistance values of Examples 1 and 2 were 10 Ω / sq, the surface resistance value of Example 3 was 4 Ω / sq, and the surface resistance value of the comparative example was 100 Ω / sq. Note that the sputtered film thickness is generally controlled by the surface resistance value ρs (ρs = ρ / t, ρ: resistivity, t: film thickness).

[0055] <Regarding the structure of the liquid crystal dimming element> A coating solution obtained by appropriately mixing a photopolymerization initiator and a black spacer with the mixture of liquid crystal A, monomer composition B, and dichroic dye shown in Table 1 was laminated on the transparent electrode substrates of the examples and the comparative example, and exposed to UV light (center wavelength 360 nm) with respect to the laminated structure of the transparent electrode substrate / dimming layer / transparent electrode substrate. The exposure conditions were set to 2 to 12 mW / cm 2 as set.

[0056] <Measurement of visible light transmittance and visible light reflectance> The visible light transmittance of the transparent electrode substrates in Examples 1-3 and the comparative example, as well as the visible light transmittance of the liquid crystal dimming elements in Examples 1-3 and the comparative example, were measured.

[0057] Visible light transmittance was defined as the average value of the transmittance in the visible light region when measured using, for example, a UH-4150 (manufactured by Hitachi High-Tech) within the measurement wavelength range of 380 nm to 1550 nm. The results are shown in Table 2.

[0058] [Table 2]

[0059] As shown in Table 2, the visible light transmittance of the transparent electrode substrate in Example 1 was 85.9%, the visible light transmittance of the transparent electrode substrate in Example 2 was 81.0%, the visible light transmittance of the transparent electrode substrate in Example 3 was 49.0%, and the visible light transmittance of the transparent electrode substrate in which the transparent electrode layer was formed with ITO was 89.6%.

[0060] Furthermore, the visible light transmittance of the liquid crystal dimming element in Example 1 when shielded from light was 3.4%, the visible light transmittance of the liquid crystal dimming element in Example 2 was 3.1%, the visible light transmittance of the liquid crystal dimming element in Example 1 was 1.2%, and the visible light transmittance of the liquid crystal dimming element in the comparative example was 4.1%.

[0061] As shown in Table 2, the transmittance of the liquid crystal dimming element in the example where the transparent electrode substrate was formed with an Ag thin film was found to be lower than that of the comparative example where ITO was used for the transparent electrode layer.

[0062] <Regarding the assumed values ​​for the transmittance ratio> As shown in Table 3 below, if we denote the visible light transmittance of the transparent electrode substrate using Ag thin film (each example) as A, and the visible light transmittance of the transparent electrode substrate using ITO (example) as B, then from Table 1, A for Example 1 is 85.9% and B is 89.6%. Therefore, the transmittance ratio (A / B) of the electrode substrate alone in Example 1 was approximately 0.96. The same calculation was performed for Examples 2 and 3.

[0063] [Table 3]

[0064] Table 3 shows (electrode substrate only). 2 That is, (A 2 ) / (B 2 It can be calculated as follows. The reason for squaring is that transparent electrode substrates are present above and below the dimming layer. (Electrode substrate alone) in Example 1 2 The transmittance ratio was approximately 0.92. The same procedure was followed for Examples 2 and 3.

[0065] The transmittance ratio of the liquid crystal dimming elements shown in Table 3 is calculated by taking the visible light transmittance of the liquid crystal dimming element in each example as C and the visible light transmittance of the liquid crystal dimming element in the comparative example as D. From Table 2, C for Example 1 is 3.43% and D is 4.09%, so the transmittance ratio (C / D) of the liquid crystal dimming element in Example 1 was approximately 0.84. The same calculation was performed for Examples 2 and 3. Thus, it was found that Examples 1 to 3 transmit less light than the comparative example. Table 4 shows the visible light reflectance of Examples 1-3 using Ag thin films and the visible light reflectance of the comparative example using ITO.

[0066] [Table 4]

[0067] The visible light reflectance was measured using a method compliant with JIS R3106:2019. As shown in Table 4, the reflection effect of the Ag thin film in Examples 1-3 was found to be higher than that of the ITO in the comparative example.

[0068] The transmittance ratio (C / D) of the liquid crystal dimming element shown in Table 3 is, in principle, (electrode substrate alone) 2 While it was predicted that the transmittance ratio would be approximately the same as the predicted value, in Example 1, the transmittance ratio (C / D) of the liquid crystal dimming element was 0.84, which was lower than the predicted value (0.92). In Examples 2 and 3, the values ​​were also lower than the predicted values.

[0069] As previously explained, this is thought to be due to improved light shielding properties resulting from the light absorption and reflection effects of the transparent electrode substrate using the Ag thin film, in addition to the light absorption of the dichroic dye.

[0070] <Regarding transmittance in the near-infrared and infrared regions> Next, the transmittance of the liquid crystal dimming elements of Examples 1-3 and the Comparative Example in the near-infrared and infrared regions was measured and compared. Near-infrared and infrared light transmittance is determined, for example, by measuring transmittance in the near-infrared and infrared regions using a device such as the UH-4150 (manufactured by Hitachi High-Tech) within the measurement wavelength range of 380 nm to 1550 nm, and then determining the average transmittance in the near-infrared and infrared regions. Table 5 shows the transmittance of the liquid crystal dimming elements of the examples and comparative examples in the near-infrared and infrared regions.

[0071] [Table 5]

[0072] As shown in Table 5, the liquid crystal dimming elements of Examples 1 to 3 showed a significantly lower transmittance in the near-infrared and infrared regions compared to the comparative example, indicating that a high heat shielding effect could be obtained.

[0073] The experimental results above show that light-shielding and heat-shielding properties can be simultaneously ensured by the light absorption of the dichroic dye and the light absorption and reflection effects of the transparent electrode layer of the Ag thin film. Therefore, it was found that by using the liquid crystal dimming element of this embodiment, it is possible to simultaneously solve the problems of preventing glare from sunlight and the problem of heat generation caused by sunlight. [Explanation of symbols]

[0074] 1: Transparent base material 2:Transparent electrode layer 3: Dimming layer 4:Transparent electrode substrate 10: Liquid crystal dimming element

Claims

1. A pair of transparent electrode substrates having a transparent electrode layer, The transparent electrode substrate is disposed inside the light-adjusting layer containing liquid crystal molecules, The light-adjusting layer contains a dichroic dye, The visible light transmittance of the transparent electrode substrate is 89% or less. The visible light reflectance of the transparent electrode substrate is 6.5% or more. A liquid crystal dimming element characterized by the following features.

2. When light is blocked, the transmittance of the liquid crystal dimming element at a wavelength of 850 nm is 60% or less, and the transmittance at a wavelength of 1550 nm is 50% or less. The liquid crystal dimming element according to feature 1.

3. A pair of transparent electrode substrates having a transparent electrode layer, The transparent electrode substrate is disposed inside the light-adjusting layer containing liquid crystal molecules, The light-adjusting layer contains a dichroic dye, The transparent electrode substrate contains silver or a silver alloy. A liquid crystal dimming element characterized by the following features.

4. The transparent electrode substrate is formed by having a silver thin film formed on the surface of the transparent substrate. The liquid crystal dimming element according to feature 3.

5. A pair of transparent electrode substrates having a transparent electrode layer, A liquid crystal dimming element having a dimming layer containing liquid crystal molecules, disposed inside the transparent electrode substrate, The light-adjusting layer contains a dichroic dye, The visible light transmittance of the aforementioned liquid crystal dimming element when it is shielded from light is 4% or less. A liquid crystal dimming element characterized by the following features.

Images