Dimming component and structure

Abstract

To provide a dimmable material capable of reducing the glare caused by reflected light included in incident light and preventing the vision from getting too dark even wearing polarized sunglasses, and provide a structure.SOLUTION: A disclosed dimmable material includes a first liquid crystal cell and a second liquid crystal cell in order from the side where incident light is incident. The first liquid crystal cell includes at least a first outer alignment film, a first liquid crystal layer, and a first inner alignment film in order from the side where the incident light is incident. The second liquid crystal cell includes at least a second inner alignment film, a second liquid crystal layer, and a second outer alignment film in order from the side where the incident light is incident. The alignment direction of the first outer alignment film and the second outer alignment film is a direction with an angle of 15° or less with the horizontal plane. The angle that is formed by the orientation direction of the first liquid crystal layer closest to the first inner alignment film and the orientation direction in the part of the second liquid crystal layer closest to the second inner alignment film in plan view, which is perpendicular to the thickness direction of the dimmable material, is 80° or more and 100° or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a dimming member and a structure.

Background Art

[0002] Conventionally, various devices have been proposed for a dimming member (dimming film) that is attached to a window to control the transmission of external light. One such dimming member uses liquid crystal. Such a dimming member using liquid crystal manufactures a liquid crystal cell by sandwiching a liquid crystal material with a transparent film material provided with transparent electrodes, and sandwiches the liquid crystal cell with linear polarizing plates, and controls the transmission of external light by changing the electric field applied to the liquid crystal to change the alignment of the liquid crystal.

[0003] In such a dimming member, various driving methods applicable to a liquid crystal display panel can be applied, and driving methods such as a VA (Vertical Alignment) method, a TN (Twisted Nematic) method, and an IPS (In-Plane-Switching) method can be applied.

[0004] Further, Patent Document 1 proposes a dimming member using a guest-host type liquid crystal. In such a liquid crystal cell having a guest-host type liquid crystal, the state in which the liquid crystal composition and the dichroic dye composition are randomly aligned and the so-called twisted alignment state are changed by electric field control to control the amount of transmitted light. In such a liquid crystal cell having a guest-host type liquid crystal, a linear polarizing plate is arranged on one surface of the liquid crystal cell, and the amount of transmitted light in the light-shielding state can be reduced.

[0005] Patent Document 2 discloses a configuration in which liquid crystal cells by a guest-host method are laminated to manufacture a liquid crystal display panel. Although it is considered that various configurations applied to a liquid crystal display panel can be applied to a dimming member, when the dimming member is arranged on a window of a vehicle, a window of a building, etc., and color tone and viewing angle characteristics are emphasized, it is desirable to apply a guest-host type liquid crystal. Furthermore, dimming components may be applied to various structures and placed in areas where external light, such as sunlight, is required to enter. Here, structures refer to buildings such as office buildings and houses, mobile vehicles such as automobiles and trains, ships and aircraft, and partitions used indoors that have openings for the purpose of transmitting light. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2013-139521 [Patent Document 2] Japanese Patent Publication No. 63-25629 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] When such light-adjusting components are used in moving objects or structural elements such as buildings, there are problems for people inside, such as the reflected light contained in the incident light being dazzling, or, if polarized sunglasses are used, the absorption of incident light making it too dark and preventing them from seeing clearly. Therefore, the purpose of this disclosure is to provide a photochromic member and structure that, when used in a moving object or a structure such as a building, can reduce glare caused by reflected light contained in incident light for people inside, and can also prevent the field of view from becoming too dark even when using polarized sunglasses. [Means for solving the problem]

[0008] The dimming member of this disclosure is a dimming member that adjusts the amount of transmitted light of incident light, and the dimming member is provided with at least a first liquid crystal cell and a second liquid crystal cell in order from the side into which the incident light is incident, and the first liquid crystal cell is provided with at least a first outer substrate, a first outer transparent electrode, a first outer alignment film, a first liquid crystal layer, a first inner alignment film, a first inner transparent electrode, and a first inner substrate in order from the side into which the incident light is incident, and the second liquid crystal cell is provided with at least a second inner substrate, a second inner transparent electrode, a second inner alignment film, a second liquid crystal layer, a second outer alignment film, a second outer transparent electrode, and A second outer substrate is provided, the first liquid crystal layer comprises a first nematic liquid crystal and a first dichroic dye composition, the second liquid crystal layer comprises a second nematic liquid crystal and a second dichroic dye composition, the first outer alignment film and the second outer alignment film are oriented in a direction where the angle with respect to the horizontal plane is 15° or less, and the angle between the orientation direction of the first nematic liquid crystal in the portion of the first liquid crystal layer closest to the first inner alignment film and the orientation direction of the second nematic liquid crystal in the portion of the second liquid crystal layer closest to the second inner alignment film, in a plan view perpendicular to the thickness direction of the dimming member, is 80° or more and 100° or less.

[0009] In the dimming member described above, neither the first inner alignment film nor the second inner alignment film is required to have undergone any alignment treatment.

[0010] The structure of the present disclosure is a structure provided with a light-adjusting member for adjusting the amount of transmitted light of incident light, wherein the light-adjusting member is provided with at least a first liquid crystal cell and a second liquid crystal cell in order from the side into which the incident light is incident, wherein the first liquid crystal cell is provided with at least a first outer substrate, a first outer transparent electrode, a first outer alignment film, a first liquid crystal layer, a first inner alignment film, a first inner transparent electrode, and a first inner substrate in order from the side into which the incident light is incident, wherein the second liquid crystal cell is provided with at least a second inner substrate, a second inner transparent electrode, a second inner alignment film, a second liquid crystal layer, a second outer alignment film, a second outer transparent electrode, and a second outer substrate in order from the side into which the incident light is incident, wherein the first liquid crystal layer comprises a first nematic liquid crystal and a first dichroic dye composition, and the second liquid crystal layer comprises a second nematic liquid crystal and a second dichroic dye composition. A structure in which the first outer alignment layer and the second outer alignment layer are oriented in a direction where the angle with respect to the horizontal plane is 15° or less, and the angle between the orientation direction of the first nematic liquid crystal in the portion of the first liquid crystal layer closest to the first inner alignment layer and the orientation direction of the second nematic liquid crystal in the portion of the second liquid crystal layer closest to the second inner alignment layer, in a plan view perpendicular to the thickness direction of the dimming member, is 80° or more and 100° or less.

[0011] In the above structure, neither the first inner orientation film nor the second inner orientation film is required to have undergone orientation treatment. [Effects of the Invention]

[0012] According to this disclosure, when a photochromic member is used in a moving object or a structure such as a building, it is possible to provide a photochromic member and structure that can reduce glare caused by reflected light contained in incident light for people inside, and that can also prevent the field of view from becoming too dark even when using polarized sunglasses. [Brief explanation of the drawing]

[0013] [Figure 1] A cross-sectional view illustrating the configuration of a dimmable film according to an embodiment of this disclosure. [Figure 2] A diagram illustrating a vehicle equipped with a dimming film according to an embodiment of this disclosure. [Figure 3] A diagram illustrating a building in which a dimming film according to the embodiment of this disclosure is installed. [Modes for carrying out the invention]

[0014] (First Embodiment) The first embodiment of this disclosure will be described below with reference to Figure 1. The following figures are schematic representations, and the size, shape, and decoration of each part have been exaggerated or simplified as appropriate to facilitate understanding. Furthermore, components not directly related to the explanation have been omitted as appropriate. In the following figures, the same parts are denoted by the same reference numerals, and some detailed explanations may be omitted.

[0015] In the following description, specific numerical values, shapes, materials, etc. are shown and described, but these can be changed as appropriate. In addition, although the terms "front surface" and "back surface" are used in this specification, there is no technical meaning in the distinction between the front surface and the back surface. When one surface of the film is defined as the front surface, the other surface is the back surface.

[0016] 〔Dimming Film (Dimming Member)〕 FIG. 1 is a schematic cross-sectional view for explaining the configuration of the dimming film according to the first embodiment. In this embodiment, an example in which a film-shaped dimming film is applied as the dimming member will be described, but it is not limited thereto. The dimming film 1 is a member that controls the amount of transmitted light transmitted by varying the electric field in the liquid crystal composition. The dimming film 1 in this embodiment has a so-called double-cell structure in which two liquid crystal cells, a first liquid crystal cell 4 and a second liquid crystal cell 104, based on the guest-host method, are stacked. The dimming film 1 is arranged at a site where incident light enters from the outside of the structure, and the first liquid crystal cell 4 and the second liquid crystal cell 104 are stacked and provided in order from the side where the incident light enters.

[0017] 〔Liquid Crystal Cell〕 The first liquid crystal cell 4 is configured by sandwiching a first liquid crystal layer 8 between a film-shaped first lower laminate 5D and a first upper laminate 5U from the side opposite to the side where the incident light enters. The second liquid crystal cell 104 is configured by sandwiching a second liquid crystal layer 108 between a film-shaped second lower laminate 105D and a second upper laminate 105U from the side opposite to the side where the incident light enters.

[0018] 〔Lower Laminate and Upper Laminate〕 The first lower laminate 5D is formed by arranging a first inner base material 6 made of a transparent film material, a first inner transparent electrode 11, a first spacer 12, and a first inner alignment film 13 in this order from the side opposite to the side where the incident light enters. The second lower laminate 105D is formed by arranging a second outer base material 106 made of a transparent film material, a second outer transparent electrode 111, a second spacer 112, and a second outer alignment film 113 in this order from the side opposite to the side where the incident light enters. The first upper laminate 5U is formed by arranging a first outer base material 15 made of a transparent film material, a first outer transparent electrode 16, and a first outer alignment film 17 in this order from the side where the incident light enters. The second upper laminate 105U is formed by arranging a second inner base material 115 made of a transparent film material, a second inner transparent electrode 116, and a second inner alignment film 117 in this order from the side where the incident light enters. The light control film 1 can individually control the transmittance of the incident light by changing the electric field applied to the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 by driving the first outer transparent electrode 16 provided on the first upper laminate 5U and the first inner transparent electrode 11 provided on the first lower laminate 5D, and by changing the electric field applied to the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 by driving the second inner transparent electrode 116 provided on the second upper laminate 105U and the second outer transparent electrode 111 provided on the second lower laminate 105D.

[0019] 〔Base material〕 The first inner base material 6, the first outer base material 15, the second outer base material 106, and the second inner base material 115 (hereinafter these four base materials are also collectively referred to as "each base materials 6, 15, 106, 115") can be applied with various transparent film materials applicable to this type of film material. In the present disclosure, each base materials 6, 15, 106, 115 is preferably a low retardation transparent film material such as a polycarbonate (PC) film or a cycloolefin polymer (COP) film. In this embodiment, although a PC film is applied to each base materials 6, 15, 106, 115, a COP film, a triacetyl cellulose (TAC) film, or the like may be applied.

[0020] 〔Transparent electrode〕 The first outer transparent electrode 16, the first inner transparent electrode 11, the second inner transparent electrode 116, and the second outer transparent electrode 111 can be made of various electrode materials applicable to this type of film material, and in this embodiment they are formed of a transparent electrode material made of ITO (Indium Tin Oxide).

[0021] [Spacer] The first spacer 12 is provided to define the thickness of the first liquid crystal layer 8, and the second spacer 112 is provided to define the thickness of the second liquid crystal layer 108, and a wide variety of resin materials can be applied. In this embodiment, the first spacer 12 and the second spacer 112 are made of photoresist. They are made by coating the first inner substrate 6, on which the first inner transparent electrode 11 is formed, with the second outer substrate 106, on which the second outer transparent electrode 111 is formed, with the respective photoresist, then exposing and developing them. The first spacer 12 may be provided on the first upper laminate 5U, or on both the first upper laminate 5U and the first lower laminate 5D. The second spacer 112 may be provided on the second upper laminate 105U, or on both the second upper laminate 105U and the second lower laminate 105D. The second spacer 112 may also be provided on the second outer alignment film 113. Furthermore, the first spacer 12 and the second spacer 112 are not limited to the photoresist described above, and for example, bead spacers may be used. The bead spacers may be scattered, or they may be added to the material when forming the alignment film and coated onto the film together with the alignment film.

[0022] [Orientation film] The first outer alignment film 17 and the second outer alignment film 113 are manufactured by rubbing a polyimide resin layer. The first outer alignment film 17 relates to the first liquid crystal layer 8, and the second outer alignment film 113 relates to the second liquid crystal layer 108. Various configurations capable of exhibiting alignment restricting force for each liquid crystal material can be applied, and they may also be manufactured using so-called photoalignment films. On the other hand, the first inner alignment film 13 and the second inner alignment film 117 are not subjected to alignment treatment. That is, the first inner alignment film 13 and the second inner alignment film 117 do not exhibit alignment restricting force for each liquid crystal material. While various materials to which photo-alignment techniques can be applied can be used as the material for the photo-alignment film, for example, a photodimerizable material can be used, which does not change orientation after being irradiated with ultraviolet light once it has been aligned. Such photodimerizable materials are disclosed in "M. Schadt, K. Schmitt, V. Kozinkov and V. Chigrinov: Jpn. J. Appl.Phys., 31, 2155 (1992)" and "M. Schadt, H. Seiberle and A. Schuster: Nature, 381, 212 (1996)," among others.

[0023] As described above, the light-adjusting film 1 is provided with a first outer alignment film 17 and a second outer alignment film 113. The first outer alignment film 17 and the second outer alignment film 113 are oriented in a direction in which the angle they make with the horizontal plane is 15° or less. This orientation direction is preferably 10° or less, more preferably 5° or less, and ideally 0°.

[0024] [Liquid crystal layer] The first liquid crystal layer 8 is formed from a solution of a first nematic liquid crystal 8A and a first dichroic dye composition 8B, and the second liquid crystal layer 108 is formed from a solution of a second nematic liquid crystal 108A and a second dichroic dye composition 108B, respectively. A wide variety of liquid crystal layer materials applicable to this type of dimmable film 1 can be used. A chiral agent may also be added.

[0025] The dimming film 1 changes the electric field of the first liquid crystal layer 8 by changing the voltage applied to the first outer transparent electrode 16 and the first inner transparent electrode 11, thereby changing the orientation of the first nematic liquid crystal 8A in vertical and horizontal orientations. It also changes the electric field of the second liquid crystal layer 108 by changing the voltage applied to the second inner transparent electrode 116 and the second outer transparent electrode 111, thereby changing the orientation of the second nematic liquid crystal 108A in vertical and horizontal orientations. In conjunction with the change in orientation of the first nematic liquid crystal 8A, the orientation direction of the first dichroic dye composition 8B changes so that the long axis direction of the first nematic liquid crystal 8A coincides with the long axis direction of the first dichroic dye composition 8B. Similarly, in conjunction with the change in orientation of the second nematic liquid crystal 108A, the orientation direction of the second dichroic dye composition 108B changes so that the long axis direction of the second nematic liquid crystal 108A coincides with the long axis direction of the second dichroic dye composition 108B.

[0026] In the first liquid crystal layer 8, the first nematic liquid crystal 8A and the first dichroic dye composition 8B are oriented in a twisted manner in a plan view perpendicular to the thickness direction of the first liquid crystal layer 8. Similarly, in the second liquid crystal layer 108, the second nematic liquid crystal 108A and the second dichroic dye composition 108B are oriented in a twisted manner in a plan view perpendicular to the thickness direction of the second liquid crystal layer 108. The thickness direction of the first liquid crystal layer 8 and the second liquid crystal layer 108 coincides with the thickness direction of the dimming film 1, and is the direction indicated by Ti in Figure 1. The first nematic liquid crystal 8A and the second nematic liquid crystal 108A are oriented parallel to the extending plane of the dimming film 1 (first liquid crystal layer 8, second liquid crystal layer 108) (so that the angle with the extending plane is 0°). This is the same in subsequent embodiments. The extending plane of the dimming film 1 is a plane perpendicular to the thickness direction of the dimming film 1, and in Figure 1, it is a plane perpendicular to Ti, which indicates the thickness direction of the dimming film 1.

[0027] Specifically, as an ideal example, the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 is twisted such that the angle with the horizontal plane is 0° at the part closest to the first outer alignment layer 17 and 45° at the part closest to the first inner alignment layer 13. Similarly, the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 is twisted such that the angle with the horizontal plane is -45° at the part closest to the second inner alignment layer 117 and 0° at the part closest to the second outer alignment layer 113. The horizontal plane is a plane perpendicular to the vertical direction (direction of gravity).

[0028] As a result, the angle between the orientation direction of the first nematic liquid crystal 8A in the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 and the orientation direction of the second nematic liquid crystal 108A in the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117, in a plan view perpendicular to the thickness direction of the dimming film 1, is 90°. This type of twisting in nematic liquid crystals (8A, 108A) can be achieved by adding a chiral agent to the liquid crystal layer (8, 108). The angle of the twist can be adjusted by the amount of chiral agent added relative to the gap corresponding to the thickness of the liquid crystal layer (8, 108).

[0029] The dimming film 1 is constructed by applying a so-called positive-type liquid crystal composition to a nematic liquid crystal, causing the nematic liquid crystal to be twisted horizontally when there is no electric field on the first liquid crystal layer 8 and the second liquid crystal layer 108, and to be vertically oriented when an electric field is applied to the first liquid crystal layer 8 and the second liquid crystal layer 108, thereby creating a so-called normally dark. A so-called negative-type liquid crystal composition may be applied to the nematic liquid crystal to create a so-called normally clear structure. Furthermore, in this disclosure, it is not a mandatory requirement that both the first nematic liquid crystal 8A and the second nematic liquid crystal 108A are twisted; it is sufficient that at least one of the first nematic liquid crystal 8A and the second nematic liquid crystal 108A is twisted. This form will be described in the second embodiment.

[0030] [Sealant] In the dimming film 1, a first sealing material 19 is arranged to surround the first liquid crystal layer 8, and this first sealing material 19 holds the first upper laminate 5U and the first lower laminate 5D together, preventing leakage of the liquid crystal material. Similarly, a second sealing material 119 is arranged to surround the second liquid crystal layer 108, and this second sealing material 119 holds the second upper laminate 105U and the second lower laminate 105D together, preventing leakage of the liquid crystal material.

[0031] The aforementioned dimming film 1 (dimming member) is placed in the area where incident light such as sunlight enters from the outside of the structure and is used to control the amount of light entering the structure. Here, "structure" refers to a mobile body represented by automobiles, trains and other vehicles, ships and aircraft, buildings represented by office buildings and houses, partitions used in rooms, etc., which transmit light and have areas where the dimming member can be placed and applied. In this embodiment, the dimming film 1 is described in an example where it is placed on a vehicle (passenger car), which is an example of a structure. However, it is not limited to this and may be applied to other structures such as buildings.

[0032] 〔vehicle〕 Figure 2 illustrates a vehicle in which the dimming film of the first embodiment is installed. Figure 2 shows the vehicle viewed from vertically above. In this embodiment, the vehicle 20 is a passenger car, and the dimming film 1 is placed in the area where incident light is incident toward the area where the occupants are seated. Specifically, as shown in Figure 2, the vehicle 20 is provided with a front window 21, a rear window 22, and side windows 23 as parts that allow light to enter the interior of the vehicle, and in this embodiment, the above-mentioned dimming film 1 is attached to multiple side windows 23. Vehicle 20 may be applied to vehicles such as trucks and buses instead of passenger cars.

[0033] Each dimming film 1, positioned in one of the multiple side windows 23, is individually connected to a power supply (not shown) and configured to have a voltage applied to it individually. This allows the vehicle 20 to individually adjust the amount of light transmitted through each side window 23.

[0034] The light-adjusting film 1 is attached to the inside of each side window 23 using an adhesive or the like. If sufficient weather resistance and other reliability can be ensured for practical purposes, it may also be attached to the outside of the vehicle. Alternatively, these windows may be constructed from laminated glass, with the light-adjusting film 1 placed between the interlayers that make up the laminated glass. The interlayer material is generally polyvinyl butyral (PVB) or ethylene vinyl acetate (EVA), but other materials may also be used. Furthermore, the transparent adhesive layer may include materials such as OCA (Optical Clear Adhesive Film) or OCR (Optical Clear Resin).

[0035] [Buildings] Next, we will describe an example of how dimmable film 1 is placed in a building, which is an example of a structural element. Figure 3 is a diagram illustrating a building in which the dimming film 1 is installed, and shows a cross-section of the building in which the dimming film is installed. In the following description and drawings, parts that perform the same functions as those of the first embodiment described above are denoted by the same reference numerals or the same reference numerals at the end, and redundant explanations are omitted as appropriate. In this embodiment, the dimming film 1 is placed in the building 30 as a structure. Specifically, the dimming film 1 is placed on the window glass 31, which is an opening in the building 30 where incident light enters the room. The dimming film 1 may also be placed on doors or other surfaces made of transparent sheet materials such as glass or transparent acrylic. Furthermore, if sufficient weather resistance and other reliability can be ensured for practical purposes, the dimming film 1 may be attached to the exterior side of the window glass 31, or it may be applied to the intermediate material of laminated glass.

[0036] Here, the incident light arriving at structures such as the vehicle 20 and the building 30 includes not only direct sunlight but also reflected light from the ground and surrounding buildings, and this reflected light contains a larger amount of horizontal polarization compared to vertical polarization. When the dimming film 1 is installed on a structure (vehicle 20, building 30, etc.), the first outer alignment film 17 and the second outer alignment film 113 are oriented in a direction where the angle they make with the horizontal plane is ideally 0°. In Figure 2, the horizontal plane is a plane parallel to the plane of the paper, and the vertical direction is perpendicular to the plane of the paper. In Figure 3, the vertical direction is the direction VD shown in the figure, and the horizontal plane is a plane perpendicular to direction VD.

[0037] As described above, by appropriately incorporating a chiral agent into the liquid crystal layer, the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 is twisted such that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17 and 45° in the portion closest to the first inner alignment film 13. The second nematic liquid crystal 108A contained in the second liquid crystal layer 108 is twisted such that the angle with the horizontal plane is -45° in the portion closest to the second inner alignment film 117 and 0° in the portion closest to the second outer alignment film 113. Here, orienting the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 so that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17 is easy because the adjacent first outer alignment film 17 is oriented so that the angle with the horizontal plane is 0°. Similarly, orienting the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 in a direction where the angle with the horizontal plane is 0° in the portion closest to the second outer alignment film 113 is easy because the adjacent second outer alignment film 113 is oriented in a direction where the angle with the horizontal plane is 0°.

[0038] Let's consider the case where incident light is incident on the light-adjusting film 1. As mentioned above, the incident light contains reflected light with a large amount of horizontal polarization, and reflected light is the cause of glare and dazzling. The horizontal polarization component of the incident light is well absorbed by the first dichroic dye composition 8B in the first liquid crystal layer 8, which is oriented so that the angle with the horizontal plane is 0° in the part closest to the first outer alignment film 17. Here, the first dichroic dye composition 8B contained in the first liquid crystal layer 8 is twisted so that the angle with the horizontal plane is 0° in the part closest to the first outer alignment film 17 and 45° in the part closest to the first inner alignment film 13. Therefore, although the horizontal polarization component of the incident light is well absorbed in the part close to the first outer alignment film 17, it becomes increasingly difficult to absorb as it approaches the first inner alignment film 13.

[0039] As explained above, since the first inner alignment layer 13 and the second inner alignment layer 117 have not undergone alignment treatment, the light transmitted through the first liquid crystal layer 8 enters the second liquid crystal layer 108 in its original state. The second nematic liquid crystal 108A contained in the second liquid crystal layer 108 is twisted such that the angle with the horizontal plane is -45° in the part closest to the second inner alignment layer 117 and the angle with the horizontal plane is 0° in the part closest to the second outer alignment layer 113. The horizontally polarized component of the incident light is not absorbed much in the part close to the second inner alignment layer 117, but is absorbed more and more as it approaches the second outer alignment layer 113. The light transmitted through the second liquid crystal layer 108 passes through the second outer alignment layer 113 and reaches the interior of the structure.

[0040] In the dimmable film 1, the horizontal polarization component contained in the incident light is moderately absorbed in the portion of the first liquid crystal layer 8 that is close to the first outer alignment film 17, and in the portion of the second liquid crystal layer 108 that is close to the second outer alignment film 113, thereby reducing glare and dazzling for people inside the structure. Furthermore, in the dimmable film 1, the portion of the second liquid crystal layer 108 closest to the interior of the structure, near the second outer alignment film 113, is oriented to have an angle of 0° with respect to the horizontal plane. Polarized sunglasses generally cut out the horizontal polarization component (the component at 0° to the horizontal direction). In other words, the polarization component cut out by the portion of the second liquid crystal layer 108 closest to the second outer alignment film 113, which is the portion of the liquid crystal layer closest to the interior of the structure, matches the polarization component cut out by polarized sunglasses. Therefore, the difference in light intensity with and without polarized sunglasses is small, and even if a person inside the structure is wearing polarized sunglasses, the field of view will not become too dark, thus avoiding a blackout.

[0041] Furthermore, by employing a guest-host system, in a plan view, the angle between the orientation direction of the first dichroic dye composition 8B (first nematic liquid crystal 8A) in the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 and the orientation direction of the second dichroic dye composition 108B (second nematic liquid crystal 108A) in the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117 is 90°. A plan view refers to the state viewed along the thickness direction of the dimming film 1, that is, the state viewed from the Ti direction in Figure 1. Therefore, the difference in transmittance due to the ON / OFF state of the electric field can be greatly increased. As described above, the light-adjusting film 1 according to the first embodiment can reduce glare caused by reflected light contained in incident light for a person inside the structure, and can also prevent the field of view from becoming too dark even when using polarized sunglasses.

[0042] (Second Embodiment) Next, the dimmable film 101 according to the second embodiment of this disclosure will be described. The dimmable film 101 according to the second embodiment differs from the dimmable film 1 according to the first embodiment only in the twisting of the liquid crystals in the first liquid crystal layer 8 and the twisting of the liquid crystals in the second liquid crystal layer 108. All other parts, including the layer configuration, materials, presence or absence of orientation treatment in each orientation film, and orientation direction, are exactly the same as those of the dimmable film 1 according to the first embodiment. Therefore, the schematic cross-sectional view illustrating the configuration of the dimmable film 101 is the same as the schematic cross-sectional view of the dimmable film 1 shown in Figure 1.

[0043] In the dimmable film 101, the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 is twisted by appropriately incorporating a chiral agent so that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17 and 90° in the portion closest to the first inner alignment film 13. On the other hand, the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 is not twisted and is oriented so that the angle with the horizontal plane is 0° in the portion closest to the second inner alignment film 117 and 0° in the portion closest to the second outer alignment film 113. In other words, in the dimmable film 101, the second nematic liquid crystal 108A and the second dichroic dye composition 108B in the second liquid crystal layer 108 are not twisted. As a result, in the dimming film 101, similar to the dimming film 1, the angle between the orientation direction of the first nematic liquid crystal 8A in the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 and the orientation direction of the second nematic liquid crystal 108A in the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117, in a plan view perpendicular to the thickness direction of the dimming film 1, is 90°.

[0044] In the dimming film 101 as well, since the first outer alignment film 17 is oriented in the direction where the angle with the horizontal plane is 0°, it is easy to orient the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 in the direction where the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17. Similarly, since the second outer alignment film 113 is oriented in the direction where the angle with the horizontal plane is 0°, it is easy to orient the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 in the direction where the angle with the horizontal plane is 0° in the portion closest to the second outer alignment film 113.

[0045] The horizontally polarized component of the incident light incident on the light-adjustable film 101 is well absorbed by the first dichroic dye composition 8B in the first liquid crystal layer 8, which is oriented so that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17. The first dichroic dye composition 8B in the light-adjustable film 101 is twisted so that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17 and 90° in the portion closest to the first inner alignment film 13. Therefore, the horizontally polarized component of the incident light is well absorbed in the portion close to the first outer alignment film 17.

[0046] Light that has passed through the first liquid crystal layer 8 enters the second liquid crystal layer 108 in the same state. The second dichroic dye composition 108B contained in the second liquid crystal layer 108 is not twisted and is oriented such that the angle it makes with the horizontal plane is 0° at any point in its thickness direction, according to the orientation direction of the second outer alignment film 113. Therefore, the horizontally polarized component of the incident light is also absorbed in the second liquid crystal layer 108. Light that has passed through the second liquid crystal layer 108 passes through the second outer alignment film 113 and reaches the interior of the structure.

[0047] As described above, the dimming film 101 also moderately absorbs the horizontal polarization component contained in the incident light, thereby reducing glare and dazzling for people inside the structure. Furthermore, similar to the first embodiment, in the second liquid crystal layer 108 of the dimming film 101, the portion closest to the second outer alignment film 113, which is the portion of the liquid crystal layer closest to the interior of the structure, is oriented to have an angle of 0° with respect to the horizontal plane. Therefore, even if a person inside the structure is wearing polarized sunglasses, the field of view will not become too dark, which has the advantage of avoiding blackout. Furthermore, by employing a guest-host system, in a planar view, the angle between the orientation direction of the first dichroic dye composition 8B (first nematic liquid crystal 8A) in the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 and the orientation direction of the second dichroic dye composition 108B (second nematic liquid crystal 108A) in the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117 is 90°. Therefore, the difference in transmittance due to the ON / OFF state of the electric field can be greatly increased. As described above, the light-adjusting film 101 according to the second embodiment can reduce glare caused by reflected light contained in incident light for a person inside the structure, and can also prevent the field of view from becoming too dark even when using polarized sunglasses.

[0048] (Other embodiments) Next, other forms of the dimmable film of the present disclosure will be described. The dimmable film of the present disclosure differs from the dimmable films 1 and 101 described above only in the twisting of the liquid crystals in the first liquid crystal layer 8 and the twisting of the liquid crystals in the second liquid crystal layer 108. In all other respects, including the layer configuration, materials, presence or absence of alignment treatment in each alignment film, and the direction of alignment, it is exactly the same as the dimmable films 1 and 101. In the dimmable film of the present disclosure, the angle between the alignment direction of the first nematic liquid crystal 8A in the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 (second liquid crystal layer 108) and the alignment direction of the second nematic liquid crystal 108A in the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117 (first liquid crystal layer 8), in a plan view perpendicular to the thickness direction of the dimmable film, is 90°.

[0049] As an example of another embodiment, the first nematic liquid crystal 8A included in the first liquid crystal layer 8 is twisted such that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17 and 60° in the portion closest to the first inner alignment film 13, and the second nematic liquid crystal 108A included in the second liquid crystal layer 108 is twisted such that the angle with the horizontal plane is -30° in the portion closest to the second inner alignment film 117 and 0° in the portion closest to the second outer alignment film 113.

[0050] Furthermore, as another example of a different embodiment, the first nematic liquid crystal 8A included in the first liquid crystal layer 8 is twisted such that the angle with the horizontal plane is 0° in the portion closest to the first outer alignment film 17 and -30° in the portion closest to the first inner alignment film 13, and the second nematic liquid crystal 108A included in the second liquid crystal layer 108 is twisted such that the angle with the horizontal plane is 60° in the portion closest to the second inner alignment film 117 and 0° in the portion closest to the second outer alignment film 113. In any of the dimmable films according to the embodiments of this disclosure, similar to dimmable films 1 and 101, the angle between the orientation direction of the first nematic liquid crystal 8A in the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 and the orientation direction of the second nematic liquid crystal 108A in the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117, in a plan view perpendicular to the thickness direction of the dimmable film 1, is 90°.

[0051] In the dimming films according to the other embodiments described above, the same effects as those described for dimming films 1 and 101 can be obtained. In the above description of dimmable films 1, 101 or dimmable films according to other embodiments, it was explained that the angle between the nematic liquid crystals (8A and 108A) in a plan view perpendicular to the thickness direction of the dimmable film, between the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 (second liquid crystal layer 108) and the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117 (first liquid crystal layer 8), is 90°. However, 90° is an ideal value, and in reality, if the angle between the nematic liquid crystals (8A and 108A) in a plan view perpendicular to the thickness direction of the dimmable film, between the portion of the first liquid crystal layer 8 closest to the first inner alignment film 13 (second liquid crystal layer 108) and the portion of the second liquid crystal layer 108 closest to the second inner alignment film 117 (first liquid crystal layer 8), is 80° or more and 100° or less, then almost the same effect as when it is 90° can be obtained. Therefore, the angle between the nematic liquid crystals (8A and 108A) in a plan view perpendicular to the thickness direction of the dimming film, between the portion of the first liquid crystal layer 8 closest to the second liquid crystal layer 108 and the portion of the second liquid crystal layer 108 closest to the first liquid crystal layer 8, can be 80° or more and 100° or less.

[0052] (Comparative example) As a comparative example, we will compare a guest-host type dimming film that is similar to dimming films 1 and 101 in all other respects, including the layer structure, materials, and the fact that the first inner alignment film 13 and the second inner alignment film 117 are not oriented, except that both the first liquid crystal layer 8 and the second liquid crystal layer 108 do not contain chiral agents, so the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 and the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 are not twisted, and consequently the orientation direction of the first outer alignment film 17 and the second outer alignment film 113 is changed. Comparative Example 1 is an example in which the first outer alignment film 17 and the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 are oriented in the direction of 0° angle with respect to the horizontal plane, and the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 and the second outer alignment film 113 are oriented in the direction of 90° angle with respect to the horizontal plane.

[0053] In Comparative Example 1, the first liquid crystal layer 8 sufficiently absorbs the horizontal polarization component contained in the incident light, thereby reducing glare and dazzling. In Comparative Example 1, the second dichroic dye composition 108B in the second liquid crystal layer 108 of the light-adjusting film, in the portion closest to the second outer alignment film 113, is oriented at an angle of 90° with respect to the horizontal plane. Therefore, the difference in light intensity with and without polarized sunglasses that cut out the component with an angle of 0° with respect to the horizontal plane becomes large. In this case, there is a risk of the field of view becoming too dark, i.e., blackout. In Comparative Example 1, the angle between the orientation direction of the first dichroic dye composition 8B (first nematic liquid crystal 8A) of the first liquid crystal layer 8 and the orientation direction of the second dichroic dye composition 108B (second nematic liquid crystal 108A) of the second liquid crystal layer 108, in a plan view perpendicular to the thickness direction of the dimming film, is 90°. Therefore, the difference in transmittance between the ON and OFF states of the electric field can be increased.

[0054] Comparative Example 2 is an example in which the first outer alignment film 17 and the first nematic liquid crystal 8A contained in the first liquid crystal layer 8 are oriented in the direction of a 90° angle with respect to the horizontal plane, and the second nematic liquid crystal 108A contained in the second liquid crystal layer 108 and the second outer alignment film 113 are oriented in the direction of a 0° angle with respect to the horizontal plane. In Comparative Example 2, the first liquid crystal layer 8 of the dimming film, which is closer to the incident light side, cannot sufficiently absorb the horizontal polarization component contained in the incident light. Therefore, glare and dazzling cannot be sufficiently reduced for people inside the structure. Furthermore, similar to the second embodiment, blackout can be avoided, and similar to Comparative Example 1, the angle between the orientation direction of the first dichroic dye composition 8B (first nematic liquid crystal 8A) of the first liquid crystal layer 8 and the orientation direction of the second dichroic dye composition 108B (second nematic liquid crystal 108A) of the second liquid crystal layer 108, in a plan view perpendicular to the thickness direction of the dimming film, is 90°, so the difference in transmittance between the ON / OFF state of the electric field can be greatly increased.

[0055] Comparative Example 3 is an example in which the first outer alignment film 17, the first nematic liquid crystal 8A contained in the first liquid crystal layer 8, the second nematic liquid crystal 108A contained in the second liquid crystal layer 108, and the second outer alignment film 113 are all oriented in the direction of 0° angle with respect to the horizontal plane. In Comparative Example 3, similar to Comparative Example 1, the horizontal polarization component contained in the incident light can be sufficiently absorbed, thus reducing glare and dazzling light. Furthermore, blackout can be avoided, similar to the second embodiment and comparative example 2. However, because the angle between the orientation direction of the first dichroic dye composition 8B (first nematic liquid crystal 8A) of the first liquid crystal layer 8 and the orientation direction of the second dichroic dye composition 108B (second nematic liquid crystal 108A) of the second liquid crystal layer 108, in a plan view perpendicular to the thickness direction of the dimming film, is 0°, the difference in transmittance between the ON / OFF state of the electric field cannot be increased.

[0056] Table 1 summarizes the effects when the dimming films according to the first embodiment, second embodiment, and comparative examples 1 to 3 described above are installed in appropriate locations on a structure and incident light is incident on them. Regarding the absorption of reflected light, products that sufficiently absorb the horizontal polarization component were marked with ○, and those that do not absorb it sufficiently were marked with ×. Regarding the field of view of polarized sunglasses, products with little concern about blackout were marked with ○, and those with a high concern were marked with ×. Regarding the ON / OFF contrast, products that can increase the contrast with the transmitted light state by sufficiently absorbing light when blocked were marked with ○, and products that cannot increase the contrast with the transmitted light state due to insufficient light-blocking performance when blocked were marked with ×. In Table 1, for the first nematic liquid crystal 8A in the first liquid crystal layer 8, the state in which it is twisted such that the angle with the horizontal plane is 0° at the part closest to the first outer alignment film 17 and 45° at the part closest to the first inner alignment film 13 is indicated as "0°→45°". Similarly, for the second nematic liquid crystal 108A in the second liquid crystal layer 108, the state in which it is twisted such that the angle with the horizontal plane is -45° at the part closest to the second inner alignment film 117 and 0° at the part closest to the second outer alignment film 113 is indicated as "-45°→0°".

[0057] [Table 1]

[0058] Table 1 shows that the photochromic film according to this disclosure exhibits excellent performance in all three indicators: reflected light absorption effect, field of view in polarized sunglasses, and ON / OFF contrast. Conversely, the photochromic films in the comparative examples fail to satisfy all three indicators simultaneously. Therefore, the superiority of the photochromic film according to this disclosure is confirmed.

[0059] The dimming members and structures related to this disclosure have been described above, but this disclosure is not limited to the embodiments described above. The embodiments described above are illustrative, and any configuration that is substantially the same as the technical idea described in the claims of this disclosure and produces similar effects is included in the technical scope of this disclosure in any case. [Explanation of Symbols]

[0060] 1. 101 Dimming Film 4. First liquid crystal cell 104 Second LCD cell 5U First Upper Laminate 105U Second Upper Laminate 5D 1st lower laminate 105D Second lower laminate 6 First inner base material 106 Second outer base material 15 First outer base material 115 Second inner base material 8. First liquid crystal layer 108 Second liquid crystal layer 11 First inner transparent electrode 111 Second outer transparent electrode 16 First outer transparent electrode 116 Second inner transparent electrode 12. First Spacer 112 Second Spacer 13. First inner orientation layer 113 Second outer orientation layer 17. First outer orientation layer 117 Second inner orientation layer 19. First sealing material 119 Second sealing material 20 vehicles 21 Front windshield 22 Rear window 23 Side windows 30 Buildings 31 Window glass

Claims

1. A dimming member that adjusts the amount of transmitted light from the incident light, The dimming member is provided with at least a first liquid crystal cell and a second liquid crystal cell in order from the side into which the incident light is incident. The first liquid crystal cell is provided with, in order from the side into which the incident light is incident, at least a first outer substrate, a first outer transparent electrode, a first outer alignment film, a first liquid crystal layer, a first inner alignment film, a first inner transparent electrode, and a first inner substrate, and the second liquid crystal cell is provided with, in order from the side into which the incident light is incident, at least a second inner substrate, a second inner transparent electrode, a second inner alignment film, a second liquid crystal layer, a second outer alignment film, a second outer transparent electrode, and a second outer substrate, The first liquid crystal layer comprises a first nematic liquid crystal and a first dichroic dye composition, and the second liquid crystal layer comprises a second nematic liquid crystal and a second dichroic dye composition. The first outer orientation film and the second outer orientation film are oriented in a direction where the angle they make with the horizontal plane is 15° or less. A dimming member wherein the angle between the orientation direction of the first nematic liquid crystal in the portion of the first liquid crystal layer closest to the first inner alignment film and the orientation direction of the second nematic liquid crystal in the portion of the second liquid crystal layer closest to the second inner alignment film, in a plan view perpendicular to the thickness direction of the dimming member, is 80° or more and 100° or less.

2. A structure provided with a dimming member that adjusts the amount of transmitted light of incident light, The dimming member is provided with at least a first liquid crystal cell and a second liquid crystal cell in order from the side into which the incident light is incident. The first liquid crystal cell is provided with, in order from the side into which the incident light is incident, at least a first outer substrate, a first outer transparent electrode, a first outer alignment film, a first liquid crystal layer, a first inner alignment film, a first inner transparent electrode, and a first inner substrate, and the second liquid crystal cell is provided with, in order from the side into which the incident light is incident, at least a second inner substrate, a second inner transparent electrode, a second inner alignment film, a second liquid crystal layer, a second outer alignment film, a second outer transparent electrode, and a second outer substrate, The first liquid crystal layer comprises a first nematic liquid crystal and a first dichroic dye composition, and the second liquid crystal layer comprises a second nematic liquid crystal and a second dichroic dye composition. The first outer orientation film and the second outer orientation film are oriented in a direction where the angle they make with the horizontal plane is 15° or less. A structure in which the angle between the orientation direction of the first nematic liquid crystal in the portion of the first liquid crystal layer closest to the first inner alignment film and the orientation direction of the second nematic liquid crystal in the portion of the second liquid crystal layer closest to the second inner alignment film, in a plan view perpendicular to the thickness direction of the dimming member, is 80° or more and 100° or less.

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