Light control film and laminated glass

Abstract

The present invention suppresses external radiation of electromagnetic noise from a light control film.　This light control film includes a first transparent electrode layer, a second transparent electrode layer, a liquid crystal layer provided between the first transparent electrode layer and the second transparent electrode layer, and a third transparent electrode layer located outside the first transparent electrode layer in an in-plane direction and having a reference potential.

Description

Dimming film and laminated glass

[0006] , ,

[0005] ,

[0001] The present disclosure relates to a dimming film and laminated glass.

[0002] A dimming film capable of switching between high and low light transmittance is known. For example, in Patent Document 1 below, a dimming film enclosed in an intermediate layer of laminated glass and capable of changing the light transmittance of the laminated glass by turning on / off a power supply is described.

[0003] Japanese Patent Application Laid-Open No. 2021-172532

[0004] In such a dimming film, electromagnetic noise is radiated from the dimming film to the outside during the operation of the dimming film. This electromagnetic noise may interfere with electrical devices such as electronic control units (ECUs), sensors, and communication devices mounted on a vehicle, causing concerns about malfunction and communication failure. Especially in in-vehicle applications, since compliance with electromagnetic compatibility (EMC) standards is required, reduction of electromagnetic noise is an important issue from the viewpoints of safety and reliability. Since the dimming film is required to have transparency and thinness, and is enclosed in an intermediate layer made of an insulating material and sandwiched between glass plates for use, it is difficult to arrange conductive members to the outside and form a shielding layer. Furthermore, since laminated glass needs to satisfy strict safety standards and durability requirements in vehicle applications, when adding electromagnetic noise countermeasures, it is required to minimize the influence on the strength, adhesiveness, and transmittance of the glass. Thus, achieving both suppression of electromagnetic noise and compatibility of optical performance and structural performance is a problem that cannot be easily achieved by the prior art, and a technology capable of suppressing the radiation of electromagnetic noise is required.

[0005] The present disclosure has been made in view of the above, and an object thereof is to provide a dimming film and laminated glass capable of suppressing electromagnetic noise radiated from the dimming film to the outside during the operation of the dimming film.

[0006] The dimming film according to the present disclosure includes a first transparent electrode layer, a second transparent electrode layer, a liquid crystal layer provided between the first transparent electrode layer and the second transparent electrode layer, and a third transparent electrode layer that is outside the first transparent electrode layer in the in-plane direction and has a reference potential.

[0007] The laminated glass according to this disclosure comprises a first glass plate and a second glass plate, and the light-adjusting film between the first glass plate and the second glass plate.

[0008] According to this disclosure, it is possible to provide a dimmable film and laminated glass that can suppress electromagnetic noise radiated to the outside from the dimmable film when the dimmable film is in operation.

[0009] Figure 1 is a block diagram of the dimming system according to the first embodiment. Figure 2 is a plan view of the laminated glass according to the first embodiment. Figure 3 is a cross-sectional view taken along line III-III in Figure 2. Figure 4 is a cross-sectional view taken along line Z-X of the dimming film according to the first embodiment. Figure 5 is a cross-sectional view taken along line V-V in Figure 2. Figure 6 is an example of the shape 1 of the third transparent electrode layer in a plan view according to the first embodiment. Figure 7 is an example of the shape 2 of the third transparent electrode layer in a plan view according to the first embodiment. Figure 8 is an example of the shape 3 of the third transparent electrode layer in a plan view according to the first embodiment. Figure 9 is an example of the shape 4 of the third transparent electrode layer in a plan view according to the first embodiment. Figure 10 is a plan view of a dimming film according to a modified example of the first embodiment. Figure 11 is a cross-sectional view taken along line Z-X of the dimming film according to the second embodiment.

[0010] Preferred embodiments of the present disclosure will be described in detail below with reference to the attached drawings. However, this disclosure is not limited to these embodiments, and if there are multiple embodiments, they may be combinations of these embodiments.

[0011] (First Embodiment) The configuration of the dimming system according to this disclosure will be described with reference to Figure 1. Figure 1 is a block diagram of the dimming system according to the first embodiment.

[0012] (Dimming System) As shown in Figure 1, the dimming system 5 includes laminated glass 100, a power supply 140, and a control device 120. The dimming system 5 according to this disclosure is mounted on a vehicle, for example. A vehicle here typically refers to an automobile, but also includes trains, ships, aircraft, and other moving objects that have glass. However, the use of the dimming system 5 is not limited to vehicles.

[0013] (Power supply) The power supply 140 outputs a predetermined output voltage to the control device 120. The output voltage output by the power supply 140 is, for example, DC 12V, but is not limited to this.

[0014] (Control device) The control device 120 is driven by the output voltage from the power supply 140, generates a drive signal to control the dimming state of the laminated glass 100, and outputs it to the laminated glass 100. The control device 120 includes, for example, an information processing device such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), and a storage device such as RAM (Random Access Memory) and ROM (Read Only Memory). The control device 120 may be implemented as a combination of hardware and software.

[0015] (Laminated Glass) The structure of laminated glass will be explained using Figure 2. Figure 2 is a plan view of laminated glass according to the first embodiment. The laminated glass 100 shown in Figure 2 is laminated glass for vehicles. Laminated glass 100 can be applied to, for example, roof glass, rear glass, side glass, quarter glass, extra glass, windshield, etc. for vehicles. Extra glass is glass installed on the rear side of a vehicle to improve the driver's rearward visibility. However, the use of laminated glass 100 is not limited to vehicles.

[0016] In Figure 2, the laminated glass 100 is shown as a flat plate, but it is not limited to this shape and may be curved in one direction or in two or more directions. Also, in Figure 2, the planar shape of the laminated glass 100 is shown as rectangular, but the planar shape of the laminated glass 100 is not limited to a rectangle and may be any shape including a trapezoid or triangle. Here, the planar shape refers to the shape of a predetermined area of ​​the laminated glass 100 as viewed from the direction normal to the interior surface of the laminated glass 100. Furthermore, in the following description, a planar view refers to viewing a predetermined area of ​​the laminated glass 100 in the Z direction (i.e., from the direction normal to the interior surface of the laminated glass 100). The first glass plate GL1, shielding layer SH, dimming film 1, power supply unit PS of the dimming film 1, and wiring WR connected to the power supply unit PS, as shown in Figure 2, will be described later.

[0017] Figure 3 is a cross-sectional view taken along line III-III in Figure 2, and is a schematic cross-sectional view of the laminated glass 100 according to this embodiment. As shown in Figure 3, the laminated glass 100 has a first glass plate GL1, an intermediate layer IL, a shielding layer SH, a light-adjusting film 1, and a second glass plate GL2. Here, the direction in which the first glass plate GL1 and the second glass plate GL2 are laminated (the lamination direction in which each layer of the light-adjusting film 1 is laminated) is defined as the Z direction, the direction from the second glass plate GL2 toward the first glass plate GL1 is defined as the Z1 direction, and the direction opposite to the Z1 direction is defined as the Z2 direction. In this case, the laminated glass 100 is laminated in the order of shielding layer SH, second glass plate GL2, intermediate layer IL, shielding layer SH, and first glass plate GL1 in the Z1 direction. The light-adjusting film 1 is provided within the intermediate layer IL. The shielding layer SH is provided as needed. In this embodiment, the Z1 direction is the direction from inside the vehicle to outside the vehicle when the laminated glass 100 is installed in the vehicle. In the following description, one direction perpendicular to the Z direction is defined as the Y direction, one direction within the Y direction is defined as the Y1 direction, and the other direction within the Y direction (opposite to the Y1 direction) is defined as the Y2 direction. Also, the direction perpendicular to the Z and Y directions is defined as the X direction, one direction within the X direction is defined as the X1 direction, and the other direction within the X direction (opposite to the X1 direction) is defined as the X2 direction. In this embodiment, when the laminated glass 100 is mounted in a vehicle, the Y direction is the front-rear direction of the vehicle and the X direction is the left-right direction of the vehicle. However, the relationship between the X and Y directions and the direction of the vehicle is not limited to this and may be arbitrary.

[0018] The total thickness T0 of the laminated glass 100 is preferably 2.8 mm or more and 10 mm or less. If the total thickness T0 of the laminated glass 100 is 2.8 mm or more, sufficient rigidity can be ensured. If the total thickness of the laminated glass 100 is 10 mm or less, sufficient transmittance can be obtained and haze (clouding) can be reduced. Note that the total thickness here, and the thickness described below, refers to the length in the Z direction.

[0019] (Glass Plates) The first glass plate GL1 and the second glass plate GL2 are glass plates facing each other. The intermediate layer IL and the light-adjusting film 1 are located between the first glass plate GL1 and the second glass plate GL2. The first glass plate GL1 and the second glass plate GL2 are fixed together with the intermediate layer IL and the light-adjusting film 1 sandwiched between them.

[0020] The first glass plate GL1 and the second glass plate GL2 may be inorganic glass or organic glass. Examples of inorganic glass include soda-lime glass, aluminosilicate glass, borosilicate glass, alkali-free glass, and quartz glass, which are used without particular limitation. The first glass plate GL1, located on the outside of the laminated glass 100, is preferably inorganic glass from the viewpoint of scratch resistance, and preferably soda-lime glass from the viewpoint of moldability. When the first glass plate GL1 and the second glass plate GL2 are soda-lime glass, clear glass, green glass containing a predetermined amount or more of iron, UV-cut green glass, and dark-colored privacy glass can be suitably used. The inorganic glass may be either untempered glass or tempered glass. Untempered glass is made by forming molten glass into a plate and slowly cooling it.

[0021] Tempered glass is made by forming a compressive stress layer on the surface of untempered glass. Tempered glass can be either physically tempered glass, such as air-cooled tempered glass, or chemically tempered glass. In the case of physically tempered glass, the glass surface can be strengthened by creating a compressive stress layer on the glass surface through a temperature difference between the glass surface and the interior of the glass, for example, by rapidly cooling a uniformly heated glass plate from a temperature near its softening point during bending, rather than by slow cooling.

[0022] On the other hand, examples of materials for organic glass include polycarbonate, acrylic resins such as polymethyl methacrylate, polyvinyl chloride, and polystyrene.

[0023] The shapes of the first glass plate GL1 and the second glass plate GL2 are not particularly limited to a rectangular shape, but may be processed into various shapes and curvatures. Gravity forming, press forming, roller forming, etc., can be used for bending the first glass plate GL1 and the second glass plate GL2. The forming method for the first glass plate GL1 and the second glass plate GL2 is also not particularly limited, but for example, in the case of inorganic glass, glass plates formed by the float method, etc., are preferred.

[0024] The thickness T1 of the first glass plate GL1 is not particularly limited, but is generally in the range of 0.1 mm to 10 mm and can be appropriately selected depending on the type and part of the vehicle to which the laminated glass 100 is applied. The minimum value of the thickness T1 of the first glass plate GL1 is preferably 0.3 mm or more, which maintains appropriate impact resistance and sufficient strength for stone chip resistance, and is preferably 0.5 mm or more, more preferably 0.7 mm or more, particularly preferably 1.1 mm or more, and most preferably 1.6 mm or more. Furthermore, the maximum value of the thickness T1 of the first glass plate GL1 is preferably 3 mm or less, which is preferable in terms of vehicle fuel efficiency as the mass of the laminated glass 100 does not become too large. The maximum value of the thickness T1 of the first glass plate GL1 is preferably 2.6 mm or less, and particularly preferably 2.1 mm or less. Here, the thickness T1 is preferably the thickness of the thinnest part of the first glass plate GL1.

[0025] The same applies to the thickness T2 of the second glass plate GL2 as to the thickness T1 of the first glass plate GL1. Note that the second glass plate GL2 may have a different composition or thickness than the first glass plate GL1. For example, the second glass plate GL2 may be thinner than the first glass plate GL1.

[0026] If the thickness T2 of the second glass plate GL2 is 1.1 mm or less, from the viewpoint of strength, it is preferable that the second glass plate GL2 is chemically strengthened glass.

[0027] A coating having water-repellent, ultraviolet or infrared-cutting functions, low reflectivity, low emissivity, or antifouling properties, a coating having condensation prevention properties, or a coating that absorbs visible light or provides coloring may be formed on the surface of at least one of the glass plates. That is, at least one of the first glass plate GL1 and the second glass plate GL2 may have one or more of the following: a water-repellent layer, an ultraviolet-blocking layer, an infrared-reflecting layer, a low reflectivity layer, a low emissivity layer, an antifouling layer, a condensation prevention layer, a visible light-absorbing layer, or a coloring layer. These layers may be present in at least one of the following: the first glass plate GL1 and the second glass plate GL2, the intermediate layer IL, the first transparent electrode layer EL1 and the second transparent electrode layer EL2 of the dimming film 1 (described later), the first substrate BM1, and the second substrate BM2.

[0028] In this embodiment, the laminated glass 100 is a laminated glass having two glass plates, a first glass plate GL1 and a second glass plate GL2, but the number of glass plates is not limited to this and may be three or more.

[0029] (Intermediate layer) The intermediate layer IL is placed between the first glass plate GL1 and the second glass plate GL2. As shown in Figure 3, the intermediate layer IL has, for example, a first intermediate layer IL1 that is joined to the first glass plate GL1 and a second intermediate layer IL2 that is joined to the second glass plate GL2. Furthermore, the intermediate layer IL has a frame-shaped third intermediate layer IL3 that is located between the first intermediate layer IL1 and the second intermediate layer IL2 and surrounds the outer periphery of the dimming film 1. However, the intermediate layer IL does not have to have the third intermediate layer IL3. Even if the third intermediate layer IL3 is not present, the outer periphery of the dimming film 1 is surrounded by at least one of the first intermediate layer IL1 and the second intermediate layer IL2 during the compression process in the manufacturing of the laminated glass 100.

[0030] The material of the intermediate layer IL can be any material, but for example, a thermoplastic resin may be used. Examples of thermoplastic resins include plasticized polyvinyl acetal resins, plasticized polyvinyl chloride resins, saturated polyester resins, plasticized saturated polyester resins, polyurethane resins, plasticized polyurethane resins, ethylene-vinyl acetate copolymer resins, ethylene-ethyl acrylate copolymer resins, cycloolefin polymer resins, ionomer resins, etc., and it is preferable to use a polyvinyl acetal resin. Examples of the above polyvinyl acetal resins include polyvinyl formal resin obtained by reacting polyvinyl alcohol (hereinafter sometimes referred to as "PVA") with formaldehyde, polyvinyl acetal resin in the narrow sense obtained by reacting PVA with acetaldehyde, and polyvinyl butyral resin (hereinafter sometimes referred to as "PVB") obtained by reacting PVA with n-butyraldehyde, and in particular, PVB is preferred.

[0031] As the intermediate layer IL, a curable transparent resin also known as Optical Clear Resin (OCR) or Liquid Optically Clear Adhesive (LOCA), or a transparent adhesive sheet also known as Optical Clear Adhesive (OCA) may be used. The intermediate layer IL may also contain functional particles such as infrared absorbers, ultraviolet absorbers, and light-emitting agents. Furthermore, the intermediate layer IL may have a colored portion called a shade band.

[0032] The thickness of the intermediate layer IL is preferably 0.3 mm or more and 3 mm or less. Within the above numerical range for the thickness of the intermediate layer IL, it is preferable that the thinnest part with the minimum value is 0.3 mm or more. If the thickness of the thinnest part of the intermediate layer IL is 0.3 mm or more, the impact resistance required for laminated glass 100 will be sufficient. If the maximum value of the thickness of the intermediate layer IL is 3 mm or less, the mass of laminated glass 100 will not become too large. Within the above numerical range for the thickness of the intermediate layer IL, it is more preferable that the maximum value of the thickness of the intermediate layer IL is 2.8 mm or less, and even more preferable that it is 2.6 mm or less. Note that the thickness of the intermediate layer IL refers to the thickness of the intermediate layer IL only, excluding the thickness of the dimming film 1. Therefore, the thickness of the intermediate layer IL refers to the length obtained by subtracting the thickness T4 of the dimming film 1 (see Figure 4) from the thickness T3 from the surface of the second intermediate layer IL2 facing the second glass plate GL2 to the surface of the first intermediate layer IL1 facing the first glass plate GL1.

[0033] The intermediate layer IL may be a single layer, or it may have two or more layers, particularly three or more layers. Furthermore, it is preferable that the first intermediate layer IL1, the second intermediate layer IL2, and the third intermediate layer IL3 included in the intermediate layer IL are all formed from the same material, but some or all of the first intermediate layer IL1, the second intermediate layer IL2, and the third intermediate layer IL3 may be formed from different materials. That is, the first intermediate layer IL1, the second intermediate layer IL2, and the third intermediate layer IL3 may be formed as a single unit, or they may be formed as separate units. In this embodiment, a part of the first intermediate layer IL1 or the second intermediate layer IL2 is molded to surround the outer periphery of the light-adjusting film 1, but the first intermediate layer IL1 and the second intermediate layer IL2 may be molded to the same size as the light-adjusting film 1.

[0034] (Shielding layer) The shielding layer SH is an opaque layer and can be provided in a strip shape along the periphery of the laminated glass 100, for example. In a plan view, as shown in Figure 2, the shielding layer SH overlaps with the periphery of the glass plate and the periphery of the light-adjusting film 1. The shielding layer SH is, for example, an opaque (for example, black) colored ceramic. The shielding layer SH may be a light-shielding colored interlayer or colored film, or a combination of a colored interlayer and colored ceramic. The colored film may be integrated with an infrared reflective film or the like. The colored interlayer or colored film may be colored as a whole, or its surface may be colored or painted.

[0035] The laminated glass 100 has an opaque shielding layer SH. The shielding layer SH suppresses the deterioration of the urethane or other resin that holds the peripheral edge of the laminated glass 100 to the vehicle body due to ultraviolet rays. In addition, the shielding layer SH conceals the power supply unit PS and wiring WR, which are electrically connected to the dimming film 1, so that they are difficult to see from at least one of the outside and inside of the vehicle.

[0036] The shielding layer SH can be formed, for example, by applying a ceramic color paste containing a molten glass frit containing a black pigment onto a glass plate by screen printing or the like, and then firing it, but is not limited to this. The shielding layer SH may also be formed, for example, by applying an organic ink containing a black or dark-colored pigment onto a glass plate by screen printing or inkjet printing, and then drying it.

[0037] In the example shown in Figure 3, the shielding layer SH is provided on the peripheral edge of the Z2-direction surface of the first glass plate GL1 and on the peripheral edge of the Z2-direction surface of the second glass plate GL2. However, it is not limited to this, and the shielding layer SH may be provided on at least one of the Z2-direction surface of the first glass plate GL1 and on the peripheral edge of the Z2-direction surface of the second glass plate GL2. Furthermore, the shielding layer SH may be provided on the peripheral edge of the Z1-direction surface of the first glass plate GL1, on the peripheral edge of the Z1-direction surface of the second glass plate GL2, or on the peripheral edge of the dimming film 1.

[0038] (Dimmable Film) The dimmable film 1 is a film whose light transmittance can be changed. The dimmable film 1 may be placed over almost the entire surface of the laminated glass 100. The planar shape of the dimmable film 1 is, for example, a rectangle smaller than the planar shape of the laminated glass 100. However, the planar shape of the dimmable film 1 does not have to be a rectangle. The peripheral edge of the dimmable film 1 is located in a position that overlaps with the shielding layer SH in a plan view. In this embodiment, the dimmable film 1 is provided on the laminated glass 100, but it is not limited to that and may be used for any application.

[0039] Figure 4 is a cross-sectional view of the dimming film according to this embodiment in the Z-Y plane. As shown in Figure 4, the dimming film 1 according to this embodiment has a first substrate BM1, a first transparent electrode layer EL1, a third transparent electrode layer EL3, a liquid crystal layer LC, a second transparent electrode layer EL2, and a second substrate BM2, and is provided between intermediate layers IL. The dimming film 1 is laminated in the order of second substrate BM2, second transparent electrode layer EL2, liquid crystal layer LC, first transparent electrode layer EL1 and third transparent electrode layer EL3, and first substrate BM1 in the Z1 direction. At this time, of the main surfaces of the dimming film 1, the surface in the Z1 direction is designated as the first main surface 1A, the main surface in the Z2 direction is designated as the second main surface 1B, and the surface connecting the first main surface 1A and the second main surface 1B is designated as the end surface 1C. In this embodiment, the first main surface 1A can be said to be the main surface of the first substrate BM1 in the Z1 direction, and the second main surface 1B can be said to be the main surface of the second substrate BM2 in the Z2 direction. Hereafter, when the first substrate BM1 and the second substrate BM2 are not distinguished, they will be referred to as substrate BM, and when the first transparent electrode layer EL1, the second transparent electrode layer EL2, and the third transparent electrode layer EL3 are not distinguished, they will be referred to as electrode layer EL. The electrode layer EL of the dimming film 1 is connected to the power supply unit PS (see Figure 2).

[0040] The thickness T4 of the dimming film 1 is, for example, 0.05 mm or more and 0.5 mm or less, and preferably 0.1 mm or more and 0.4 mm or less. A power supply unit PS connected to the dimming film 1 is connected to an extraction wiring WR for connecting the power supply unit PS to an external circuit (see Figure 2).

[0041] (Substrate) The first substrate BM1 and the second substrate BM2 are a pair of substrates that support the electrode layer EL and sandwich the liquid crystal layer LC. The first substrate BM1 is disposed at a position in the Z1 direction relative to the liquid crystal layer LC, supports the first transparent electrode layer EL1 and the third transparent electrode layer EL3, and the second substrate BM2 is disposed at a position in the Z2 direction relative to the liquid crystal layer LC and supports the second transparent electrode layer EL2.

[0042] The substrate BM is preferably a transparent resin layer. The substrate BM preferably contains one or more selected from the group consisting of, for example, polyethylene terephthalate, polyethylene naphthalate, polyamide, polyether, polysulfone, polyethersulfone, polycarbonate, polystyrene, cyclic polyolefin, polyarylate, polyetherimide, polyetheretherketone, polyimide, aramid, polybutylene terephthalate, triacetyl cellulose, polyurethane, and cycloolefin polymer.

[0043] Note that the first substrate BM1 and the second substrate BM2 are, for example, composed of the same materials as those shown above, but are not limited thereto, and may be composed of different materials.

[0044] The thickness T5 of the substrate BM is, for example, 5 μm or more and 500 μm or less, preferably 10 μm or more and​​​​​(Electrode layer) The electrode layer EL is a layer to which a signal is applied from the control device 120. For the electrode layer EL, for example, a transparent conductive oxide (TCO: transparent conductive oxide) can be used. Examples of TCO include, but are not limited to, tin-doped indium oxide (ITO: tin-doped indium oxide), aluminum-doped zinc oxide (AZO: aluminum-doped zinc oxide), and indium-doped cadmium oxide.

[0047] As the electrode layer EL, a transparent conductive polymer such as poly(3,4-ethylenedioxythiophene) (PEDOT) or poly(4,4-dioctylcyclopentadithiophene) can also be preferably used. Further, as the electrode layer EL, a laminated film of a metal phase and a dielectric layer, silver nanowires, a metal mesh of silver or copper, etc. can also be preferably used.

[0048] The electrode layer EL according to the present embodiment includes a first transparent electrode layer EL1, a second transparent electrode layer EL2, and a third transparent electrode layer EL3. Each configuration will be described below.

[0049] (First transparent electrode layer) The first transparent electrode layer EL1 is formed on the surface of the first base material BM1 in the Z2 direction and is in contact with the surface of the liquid crystal layer LC in the Z1 direction. And the first transparent electrode layer EL1 is connected to the control device 120 via the power supply unit PS, and a signal is applied under the control of the control device 120. Specifically, an alternating voltage is applied to the first transparent electrode layer EL1 according to the present embodiment. The frequency of the alternating voltage may be appropriately set according to the type of the dimming film used, and is, for example, 30 Hz to 100 Hz. The thickness of the first transparent electrode layer EL1 is preferably 30 nm or more and 200 nm or less because it is easy to ensure conductivity. In this numerical range, 50 nm or more is more preferable, and 60 nm or more is even more preferable. The thickness of the first transparent electrode layer EL1 is preferably 200 nm or less in this numerical range because it is easy to ensure transparency, more preferably 180 nm or less, and even more preferably 160 nm or less.

[0050] (Second Transparent Electrode Layer) The second transparent electrode layer EL2 is formed on the Z1 direction surface of the second substrate BM2 and is in contact with the Z2 direction surface of the liquid crystal layer LC. That is, the first transparent electrode layer EL1 and the second transparent electrode layer EL2 are a pair of electrode layers sandwiching the liquid crystal layer LC. Furthermore, the second transparent electrode layer EL2 is superimposed on both the first transparent electrode layer EL1 and the third transparent electrode layer EL3, which will be described later, when viewed from the stacking direction (Z direction). The second transparent electrode layer EL2 has a reference potential. In other words, the potential of the second transparent electrode layer EL2 is the reference potential. The reference potential refers to a specific potential point in the circuit, and that potential point functions as a reference for comparison with other potentials. The reference potential can be set at any position in the circuit. The reference potential may have an absolute value smaller than the peak voltage value of the voltage (AC voltage in this embodiment) applied to the first transparent electrode layer EL1. Normally, the vehicle body functions as ground (hereinafter also referred to as "GND"). By electrically connecting a predetermined component (e.g., a transparent electrode layer) included in the dimming film to the vehicle's ground, a common reference potential can be set with other electronic components in the vehicle, thereby suppressing the effects of electromagnetic noise. The predetermined component included in the dimming film can also be set to the reference potential by connecting it to the vehicle's body via, for example, the negative terminal of the vehicle's battery or the ground plane in the electronic control unit (ECU). In this embodiment, the reference potential is set to 0V, and the second transparent electrode layer EL2 according to this embodiment has a potential of 0V, which is equal to GND (the potential of the second transparent electrode layer EL2 is 0V). However, the value of the reference potential is not limited to 0V. The preferred thickness of the second transparent electrode layer EL2 is the same as the preferred thickness of the first transparent electrode layer EL1.

[0051] (Third transparent electrode layer) Here, the direction along the main surface of the dimming film 1 is defined as the in-plane direction, the direction from the end face 1C of the dimming film 1 toward the center of the dimming film 1 as viewed from the Z direction is defined as the inside of the in-plane direction, and the direction from the center of the dimming film 1 toward the end face 1C is defined as the outside of the in-plane direction. That is, in the example of Figure 4, the direction from the right (Y1 direction) end face 1C toward the center of the dimming film 1 and the direction from the left (Y2 direction) end face 1C toward the center of the dimming film 1 are the inside of the in-plane direction. The direction from the center of the dimming film 1 toward the right end face 1C and the direction from the center of the dimming film 1 toward the left end face 1C are the outside of the in-plane direction. The third transparent electrode layer EL3 is located on the outside of the in-plane direction of the first transparent electrode layer EL1. The third transparent electrode layer EL3 is not electrically connected to the first transparent electrode layer EL1. The third transparent electrode layer EL3 is electrically connected to the second transparent electrode layer EL2. As shown in Figure 4, the third transparent electrode layer EL3 is formed on the Z2-direction surface of the first substrate BM1 at a distance t1 away from the first transparent electrode layer EL1 in the in-plane direction. The specific shape of the third transparent electrode layer EL3 when viewed in plan will be described later. The third transparent electrode layer EL3, like the second transparent electrode layer EL2, has a reference potential. For example, the third transparent electrode layer EL3 in this embodiment has a potential of 0V, which is equal to GND. The third transparent electrode layer EL3 and the second transparent electrode layer EL2 are at the same potential and may be physically connected by an electric wire or the like. The in-plane width T6 of the third transparent electrode layer EL3 is, for example, 1 mm or more and 300 mm or less, preferably 5 mm or more and 100 mm or less, and more preferably 10 mm or more and 50 mm or less. The preferred thickness of the third transparent electrode layer EL3 is the same as the preferred thickness of the first transparent electrode layer EL1. From the viewpoint of enhancing the effect of suppressing electromagnetic noise radiated to the outside, the area of ​​the third transparent electrode layer EL3 is preferably 0.01% to 100% of the area of ​​the first transparent electrode layer EL1, and within this numerical range, 0.05% or more is more preferable, preferably 0.1% or more, even more preferable 0.5% or more, and particularly preferable 1% or more. From the viewpoint of ensuring a sufficiently dimmable area, the area of ​​the third transparent electrode layer EL3 is preferably less than or equal to the area of ​​the first transparent electrode layer EL1.In other words, the area of ​​the third transparent electrode layer EL3 is preferably 0.01% or more and 100% or less of the area of ​​the first transparent electrode layer EL1, and within this numerical range, less than 100% is more preferable, 99% or less is even more preferable, and for example, 95% or less is also acceptable.

[0052] The third transparent electrode layer EL3 is preferably positioned to overlap with the shielding layer SH in the Z direction. More preferably, when viewed from the Z direction, the entire area of ​​the third transparent electrode layer EL3 overlaps with the shielding layer SH. This suppresses the visibility of the third transparent electrode layer EL3, whose transmittance does not change.

[0053] In this embodiment, the third transparent electrode layer EL3 is located on the in-plane side of the electrode layer EL on the Z1 side (first transparent electrode layer EL1), but is not limited to this. For example, if the electrode layer EL on the Z2 side is called the first transparent electrode layer, the third transparent electrode layer EL3 may be located on the in-plane side of the first transparent electrode layer on the Z2 side (second transparent electrode layer EL2 in the example of Figure 4).

[0054] (Method for forming the third transparent electrode layer) The third transparent electrode layer EL3 may be formed by any method. For example, the first transparent electrode layer EL1, which is formed over the entire surface of the Z2 direction of the first substrate BM1, may be divided into two electrode layers by irradiating it with a focused laser to create a gap t1, and one of these may be made the third transparent electrode layer EL3. Alternatively, the first transparent electrode layer EL1 may be divided into two electrode layers by cutting the first substrate BM1 and the first transparent electrode layer EL1 with a light-adjusting film 1, which is formed over the entire surface of the Z2 direction of the first substrate BM1, to create a gap t1, and one of these may be made the third transparent electrode layer EL3. From the viewpoint of preventing migration, the in-plane width of the gap t1 is preferably 6 μm to 200 μm when the gap t1 is formed by laser processing, and preferably 1 mm to 15 mm when the gap t1 is formed by machining. Furthermore, within the above numerical range, if the in-plane width of the gap t1 formed by machining is 15 mm or less, the effect of suppressing electromagnetic noise radiated to the outside is less likely to weaken, which is preferable, but it may also be 10 mm or less, or 5 mm or less.

[0055] (Electromagnetic noise suppression effect of the third transparent electrode layer) The dimming film 1 controls the transmittance of the liquid crystal layer LC by the electric field generated by the potential difference between the first transparent electrode layer EL1 and the second transparent electrode layer EL2. In other words, the dimming film 1 changes the potential difference between the first transparent electrode layer EL1 and the second transparent electrode layer EL2 by switching the power ON / OFF, and controls the electric field with the changed potential difference to control the transmittance of light in the liquid crystal layer LC. When an electric field is generated between the first transparent electrode layer EL1 and the second transparent electrode layer EL2, electromagnetic noise is radiated from the first transparent electrode layer EL1, which has a higher potential than the second transparent electrode layer EL2, toward the outside of the dimming film 1. Specifically, electromagnetic noise is radiated from the Z1 direction surface of the first transparent electrode layer EL1 toward the Z1 direction (in this embodiment, toward the direction from inside the vehicle to outside the vehicle), and electromagnetic noise is radiated from the X and Y directions ends of the first transparent electrode layer EL1 toward the outside in the in-plane direction. In other words, electromagnetic noise is radiated in the direction opposite to the direction of the electric field moving from the first transparent electrode layer EL1 to the second transparent electrode layer EL2, and in a direction perpendicular to the direction of the electric field. In this embodiment, the dimming film 1 has a third transparent electrode layer EL3 whose potential is equal to the reference potential (0V) on the outside in the in-plane direction of the first transparent electrode layer EL1. As a result, an electric field is generated from the X and Y ends of the first transparent electrode layer EL1 toward the third transparent electrode layer EL3 which is on the outside in the in-plane direction. This makes it possible to suppress the electromagnetic noise that was originally radiated from the X and Y ends of the first transparent electrode layer EL1 toward the outside in the in-plane direction.

[0056] (Liquid Crystal Layer) The liquid crystal layer LC is a layer whose light transmittance and haze can be changed. The liquid crystal layer LC is located between the first substrate BM1 on which the first transparent electrode layer EL1 is formed and the second substrate BM2 on which the second transparent electrode layer EL2 is formed. In other words, the liquid crystal layer LC is located between the first transparent electrode layer EL1 and the second transparent electrode layer EL2. The liquid crystal layer LC according to this embodiment is a polymer dispersed liquid crystal (PDLC). However, the liquid crystal layer (LC) is not limited to PDLC; for example, it may be polymer network liquid crystal (PNLC), guest-host liquid crystal (GHLC), or suspended particle device (SPD).

[0057] Polymer-dispersed liquid crystals (PDLCs) are components having an active layer in which droplet-shaped liquid crystals are dispersed and held within a transparent polymer medium. Applying a voltage to the electrode layer changes the arrangement of the droplet liquid crystals held in the active layer. As a result, the active layer changes the intensity of light scattering in accordance with the voltage applied to the electrode layer. The degree of light scattering can be expressed, for example, as haze.

[0058] Guest-host liquid crystal (GHLC) is a component having an active layer formed by mixing a dichroic dye (guest), which has anisotropy in light absorption in the long axis and short axis directions of the molecule, with a liquid crystal material (host). By applying a voltage to the electrode layer, the orientation of the liquid crystal molecules held in the active layer changes. As a result, the active layer changes the degree of absorption of incident light in accordance with the voltage applied to the electrode layer.

[0059] Although the liquid crystal layer LC and the gap t1 are not separated by a material, the liquid crystal layer LC in this embodiment is a polymer-dispersed liquid crystal (PDLC), so the liquid crystal is held in place by the polymer, and the inflow of liquid crystal into the gap t1 is suppressed. However, the gap t1 and the liquid crystal layer LC may be separated by a material.

[0060] (Power supply unit) The power supply unit PS is connected to the electrode layer EL and applies a signal from the control device 120 to the electrode layer EL. In the example in Figure 2, the power supply unit PS is located at the periphery of the edge of the dimming film 1 that extends in the Y direction when viewed in plan, but the position of the power supply unit PS is not limited to that and can be arbitrary; for example, it may be located at the periphery of the edge that extends in the X direction.

[0061] Figure 5 is a cross-sectional view taken along the line V-V in Figure 2. Figure 5 shows a cross-sectional view of the dimming film according to this embodiment in the Z-Y plane. As shown in Figure 5, the power supply unit PS is electrically connected from inside the liquid crystal layer LC to the first transparent electrode layer EL1, the second transparent electrode layer EL2, and the third transparent electrode layer EL3, respectively. Specifically, the first transparent electrode layer EL1 is connected to the power supply unit PS1, the second transparent electrode layer EL2 is connected to the power supply unit PS2, and the third transparent electrode layer EL3 is connected to the power supply unit PS3. In addition, a cover CV may be optionally provided around the power supply unit PS located inside the liquid crystal layer LC and the wiring WR connected to the power supply unit PS. The cover CV may be made of any material, but it is desirable that it be an insulating material in order to prevent unexpected current flow to the electrode layer EL and the liquid crystal layer LC. The power supply units PS1 and PS2 drive the liquid crystal layer LC by supplying current to the first transparent electrode layer EL1 and the second transparent electrode layer EL2.

[0062] Of the power supply units PS connected to the first transparent electrode layer EL1 and the second transparent electrode layer EL2, one power supply unit PS1 is, for example, a positive electrode and is connected to the positive side of a power source 140, such as a battery mounted on the vehicle, via electrically connected wiring WR. The other power supply unit PS2 is, for example, a negative electrode and is connected to the negative side of a power source 140, such as a battery mounted on the vehicle, via electrically connected wiring WR. The wiring WR may be formed integrally with the power supply units PS.

[0063] When a voltage is applied to the liquid crystal layer LC from a power source 140 such as a battery via the power supply unit PS, the transmittance of the liquid crystal layer LC switches according to the voltage.

[0064] The material of the power supply section PS is not particularly limited as long as it is a conductive material, but examples include metallic materials. Examples of metallic materials include gold, silver, copper, or tin. Furthermore, these metals may be plated, or they may be composed of alloys or composites with resin.

[0065] From the viewpoint of cost and availability, metal ribbons such as copper, flat braided copper wire, or FPC (Flexible Printed Circuit) can be suitably used for the power supply section PS. The metal ribbons or flat braided copper wire may be plated with metals other than copper. The power supply section PS may be formed integrally with the wiring WR.

[0066] The power supply section PS can be joined to the electrode layer EL by a conductive adhesive (conductive adhesive layer), an anisotropic conductive film, or solder. Alternatively, the power supply section PS may be in direct contact with the electrode layer EL without the use of a conductive adhesive, anisotropic conductive film, or solder. Furthermore, the power supply section PS may be formed by a printing method such as screen printing, inkjet printing, offset printing, flexographic printing, or gravure printing.

[0067] The power supply unit PS has a length and shape that is necessary and sufficient for supplying current to the liquid crystal layer LC. The shape of the power supply unit PS is not particularly limited and can be, for example, roughly rectangular or L-shaped. Since the power supply unit PS needs to be concealed by the shielding layer SH, it is arranged, for example, at one end (one side) in the longitudinal direction of the liquid crystal layer LC, approximately parallel to the peripheral edges of the first glass plate GL1 and the second glass plate GL2 (see Figure 2).

[0068] The power supply unit PS is preferably positioned at a location of 5 mm or more in-plane from the end faces of the peripheral edges of the first glass plate GL1 and the second glass plate GL2, and more preferably at a location of 8 mm or more in-plane. This arrangement reduces the risk of moisture entering from the peripheral edges of the first glass plate GL1 and the second glass plate GL2, which could lead to corrosion of the power supply unit PS or short circuits between the different potentials.

[0069] The length w in the short direction of the power supply section PS shown in Figure 2 (= width of the power supply section PS) is preferably 3 mm to 200 mm, more preferably 4 mm to 150 mm, and even more preferably 4 mm to 100 mm. Setting the length w in the short direction of the power supply section PS to 3 mm or more improves handling and ensures sufficient contact area with the first transparent electrode layer EL1 and the second transparent electrode layer EL2, thereby enabling the power supply section to fully perform its function. Furthermore, setting the length w in the short direction of the power supply section PS to 200 mm or less facilitates concealment by the shielding layer SH, improving the design.

[0070] The thickness of the power supply section PS is preferably 0.05 mm to 0.4 mm. By making the thickness of the power supply section PS 0.05 mm or more, sufficient strength can be obtained, thereby suppressing the occurrence of defects such as wire breakage. Furthermore, by making the thickness of the power supply section PS 0.4 mm or less, the thickness deviation between the electrode and other parts is reduced. This makes it possible to suppress the stress generated in the first glass plate GL1 and the second glass plate GL2, and reduces the risk of the first glass plate GL1 and the second glass plate GL2 cracking.

[0071] As shown in Figure 5, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 in this embodiment are physically connected by wiring WR via power supply units PS2 and PS3. As a result, the third transparent electrode layer EL3 in this embodiment has the same potential as the second transparent electrode layer EL2, 0V (GND). In other words, the dimming film 1 in this embodiment has a third transparent electrode layer EL3 whose potential is equal to the reference potential (0V) on the outside in the in-plane direction of the first transparent electrode layer EL1, so that an electric field is generated from the edge of the first transparent electrode layer EL1 toward the third transparent electrode layer EL3 which is on the outside in the in-plane direction. This makes it possible to suppress electromagnetic noise that was originally radiated from the edge of the first transparent electrode layer EL1 toward the outside in the in-plane direction.

[0072] (Wiring) The wiring WR connecting the power supply units PS according to this embodiment may be made of any conductive material. For example, the wiring WR may be a flat harness in which a conductor such as an FPC is sealed in an insulating film, or it may be a wire harness. Alternatively, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 may be connected by a conductive structure such as a through-hole.

[0073] (Example of the shape of the third transparent electrode layer in plan view) The third transparent electrode layer EL3 may have any shape located outside the in-plane direction of the first transparent electrode layer EL1, but the following describes an example of the shape of the third transparent electrode layer EL3 in plan view.

[0074] (Shape Example 1) Figure 6 shows Shape Example 1 of the third transparent electrode layer in a plan view according to this embodiment. As shown in Figure 6, the third transparent electrode layer EL3 according to this example has sections L1, L2, and L3. Here, section L1 is the section of the third transparent electrode layer EL3 that extends in the Y direction. Section L2 is the section that extends in the X2 direction from the Y1 direction end and the Y2 direction end of section L1, respectively. Section L3 is the section that connects the X2 direction ends of the two sections L2. Here, section L3 is located on the side of the dimming film 1 with the power supply section PS when viewed in plan. Section L1 is located in the X1 direction further than section L3, and in this example, it is located on the side opposite to the side with the power supply section PS. In this example, when viewed in plan, the third transparent electrode layer EL3 surrounds the entire circumference of the first transparent electrode layer EL1 with a gap t1 between them. This makes it possible to suppress electromagnetic noise radiated from the dimming film 1 toward the outward direction in the in-plane direction of the dimming film 1.

[0075] As described above, the first transparent electrode layer EL1 is connected to the power supply unit PS1, and the second transparent electrode layer EL2 is connected to the power supply unit PS2. In this example, the third transparent electrode layer EL3 is connected to the power supply unit PS3 in section L3. The power supply units PS3 and PS2 are connected to the wiring WR, so that the third transparent electrode layer EL3 and the second transparent electrode layer EL2 are at the same potential (0V). At this time, in the third transparent electrode layer EL3, at a position away from the position on section L3 connected to the power supply unit PS3 (for example, on section L1), the potential of the third transparent electrode layer EL3 may not be completely equal to that of the second transparent electrode layer EL2, and electromagnetic noise emitted from that position may not be sufficiently suppressed. Therefore, in order to bring the entire areas of the second transparent electrode layer EL2 and the third transparent electrode layer EL3 closer to the same potential, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 may have points of electrical connection via the wiring WR other than the power supply unit PS. Specifically, in this example, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 are connected to terminal TE, which is connected to each other by wiring WR. In other words, terminal TE2 on the second transparent electrode layer EL2 and terminal TE3 on the third transparent electrode layer EL3 are electrically connected via wiring WR. The position of terminal TE connecting the second transparent electrode layer EL2 and the third transparent electrode layer EL3, other than the power supply unit PS, can be arbitrary, but it is desirable that it be located as far away from the power supply unit PS as possible. In this example, since the power supply unit PS3 is near the end in the Y2 direction of section L3, it is desirable that terminal TE3 be located near the end in the Y1 direction of section L1.

[0076] The material of terminal TE is not particularly limited as long as it is a conductive material, but examples include metallic materials. Examples of metallic materials include gold, silver, copper, aluminum, tungsten, platinum, palladium, nickel, cobalt, titanium, iridium, zinc, magnesium, or tin. These metals may also be plated, or they may be composed of alloys or composites with resin.

[0077] From the viewpoint of cost and availability, copper ribbon, flat braided copper wire, or FPC can be suitably used for the terminal TE. The copper ribbon or flat braided copper wire may be plated with a metal other than copper. The terminal TE may be formed integrally with the wiring WR.

[0078] The terminal TE can be joined to the electrode layer EL by a conductive adhesive (conductive adhesive layer), an anisotropic conductive film, or solder. Alternatively, the power supply part PS may be in direct contact with the electrode layer EL without the use of a conductive adhesive, anisotropic conductive film, or solder. Alternatively, the terminal TE may be formed by a printing method such as screen printing, inkjet printing, offset printing, flexographic printing, or gravure printing.

[0079] (Shape Example 2) In Shape Example 1, the shape of the third transparent electrode layer EL3 surrounding the entire circumference of the first transparent electrode layer EL1 was described. However, the shape of the third transparent electrode layer EL3 may also be such that it surrounds only a portion of the entire circumference of the first transparent electrode layer EL1. Figure 7 shows Shape Example 2 in plan view of the third transparent electrode layer according to this embodiment. As shown in Figure 7, the third transparent electrode layer EL3 according to this example surrounds a portion of the entire circumference of the first transparent electrode layer EL1 with a gap t1 between them. More specifically, the third transparent electrode layer EL3 surrounds three of the four sides of the first transparent electrode layer EL1 with sections L1 and L2 of the third transparent electrode layer EL3. Here, the definitions of sections L1 and L2 are the same as in Shape Example 1, so the explanation is omitted. Furthermore, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 are connected via wiring WR at terminal TE2 on the second transparent electrode layer EL2 and terminal TE3 on the third transparent electrode layer EL3. As a result, the dimming film 1 according to this example can suppress electromagnetic noise radiated outward in the in-plane direction from three of the four sides of the first transparent electrode layer EL1 that are surrounded by the third transparent electrode layer EL3. Here, the region of the liquid crystal layer LC that overlaps with the third transparent electrode layer EL3, which is at the same potential as the second transparent electrode layer EL2, cannot have its transmittance controlled. In other words, by limiting the direction in which electromagnetic noise radiation is suppressed and reducing the area of ​​the third transparent electrode layer EL3, the area in which transmittance can be controlled can be expanded compared to shape example 1. Note that the position of terminal TE, which electrically connects the second transparent electrode layer EL2 and the third transparent electrode layer EL3 via wiring WR in this example, may be set arbitrarily, and the number of terminals may also be set arbitrarily.

[0080] (Shape Example 3) In Shape Example 2, the shape of the third transparent electrode layer EL3 was described in which the third transparent electrode layer EL3 surrounds three of the four sides of the first transparent electrode layer EL1. However, the shape of the third transparent electrode layer EL3 may be such that, when viewed in plan, it exists only on the in-plane outer side of one or two of the four sides of the first transparent electrode layer EL1. Figure 8 shows Shape Example 3 of the third transparent electrode layer EL3 in plan view according to this embodiment. As shown in Figure 8, the dimming film 1 according to this example has a third transparent electrode layer EL3 that, when viewed in plan, is separated from one of the four sides of the first transparent electrode layer EL1 by a gap t1 on the in-plane outer side. More specifically, the dimming film 1 has the third transparent electrode layer EL3 on the in-plane outer side of the side of the first transparent electrode layer EL1 that extends in the Y direction and is opposite to the side with the power supply part PS. Furthermore, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 are connected via wiring WR at terminal TE2 on the second transparent electrode layer EL2 and terminal TE3 on the third transparent electrode layer EL3, and have the same potential. As a result, the dimmable film 1 according to this example can suppress electromagnetic noise radiated outward in the in-plane direction from one of the four sides of the first transparent electrode layer EL1 where the third transparent electrode layer EL3 is located on the outward side in the in-plane direction. In other words, the dimmable film 1 according to this example can suppress electromagnetic noise radiated from the dimmable film 1 only on the side where there is a device that is affected by electromagnetic noise and is located around the laminated glass, by providing the third transparent electrode layer EL3 only on the side where there is a device. Note that in this example, the dimmable film 1 had the third transparent electrode layer EL3 on the outward side in the in-plane direction of the side of the first transparent electrode layer EL1 that extends in the Y direction, but the third transparent electrode layer EL3 may also be located on the outward side in the in-plane direction of the side of the first transparent electrode layer EL1 that extends in the X direction. Furthermore, the position of the power supply unit PS and the position of the terminal TE may be set arbitrarily.

[0081] (Shape Example 4) In Shape Example 3, the shape of the third transparent electrode layer EL3 was described such that, when viewed in plan, it exists only on the in-plane outer side of one of the four sides of the first transparent electrode layer EL1. However, the shape of the third transparent electrode layer EL3 may also be such that it exists only on the in-plane outer side of a portion of one of the four sides of the first transparent electrode layer EL1. Figure 9 is Shape Example 4 of the third transparent electrode layer EL3 in plan view according to this embodiment. As shown in Figure 9, the dimming film 1 according to this example has a third transparent electrode layer EL3 that is separated from the first transparent electrode layer EL1 by a gap t1 in a portion of one of the four sides of the first transparent electrode layer EL1 when viewed in plan view. More specifically, the dimming film 1 has a third transparent electrode layer EL3 that is separated from the first transparent electrode layer EL1 by a gap t1 in a portion of the side on the Y1 side of the side extending in the X direction of the first transparent electrode layer EL1. In other words, a portion of the edge of the first transparent electrode layer EL1 in the Y1 direction is recessed in the Y2 direction, and the third transparent electrode layer EL3 is provided within this recess. If the end face forming the recess of the first transparent electrode layer EL1 is called the end face 1D, then the end face 1D surrounds the third transparent electrode layer EL3. Furthermore, the second transparent electrode layer EL2 and the third transparent electrode layer EL3 are connected via wiring WR at terminal TE2 on the second transparent electrode layer EL2 and terminal TE3 on the third transparent electrode layer EL3. The dimming film 1 according to this example can suppress electromagnetic noise radiated in the Y1 direction from the end face 1D of the first transparent electrode layer EL1. In other words, the dimming film 1 according to this example can suppress electromagnetic noise radiated from a portion of the area close to a device on the side of the laminated glass where the device is affected by electromagnetic noise, by having the third transparent electrode layer EL3 only in a portion of the area close to the device. In this example, the dimming film 1 had a third transparent electrode layer EL3 on the in-plane outer side of a portion of the edge extending in the X direction of the first transparent electrode layer EL1. However, the third transparent electrode layer EL3 may also be located on the in-plane outer side of a portion of the edge extending in the Y direction of the first transparent electrode layer EL1. Furthermore, the position of the power supply unit PS and the position of the terminal TE may be set arbitrarily.

[0082] (Effects) As described above, the dimming film 1 according to this embodiment has a third transparent electrode layer EL3 located on the outside in the in-plane direction of the first transparent electrode layer EL1 and having the same reference potential as the second transparent electrode layer EL2, thereby suppressing electromagnetic noise radiated from the end face of the first transparent electrode layer EL1 on the side where the third transparent electrode layer EL3 is located.

[0083] Up to this point, we have described the case in which one first transparent electrode layer EL1 and one second transparent electrode layer EL2 receive a signal from the control device 120 via the power supply unit PS. However, it is also possible for multiple first transparent electrode layers EL1 and one second transparent electrode layer EL2 to receive a signal via the power supply unit PS. Below, we will describe a modified example of the first embodiment in which multiple first transparent electrode layers EL1 and one second transparent electrode layer EL2 receive a signal from the control device 120 via the power supply unit PS. Note that components that are common to the first embodiment will be omitted from the description.

[0084] (Modified Version of the First Embodiment) Figure 10 is a plan view of a dimmable film according to a modified version of the first embodiment. As shown in Figure 10, in this modified version, the control device 120 applies signals to a plurality of first transparent electrode layers EL1 and one second transparent electrode layer EL2 via a power supply unit PS. Specifically, the first transparent electrode layer EL1 is divided in the Y direction into transparent electrode layer EL1a, transparent electrode layer EL1b, transparent electrode layer EL1c, and transparent electrode layer EL1d, and signals from the control device 120 are applied via wiring WR to the power supply unit PS1a connected to each transparent electrode layer, to the power supply unit PS1d, and to the power supply unit PS2 connected to the second transparent electrode layer EL2. Furthermore, the dimmable film 1 according to this modified version has a third transparent electrode layer EL3 that is at the same potential as the second transparent electrode layer EL2, located outside the first transparent electrode layer EL1 in the in-plane direction at a distance of gap t1. In the example shown in Figure 10, the shape of the third transparent electrode layer EL3 is shown as enclosing the entire circumference of the first transparent electrode layer EL1, but it is not limited to this, and it may be a shape that encloses only a part of the entire circumference of the first transparent electrode layer EL1. The function and shape examples of the third transparent electrode layer EL3 are the same as in the first embodiment, so the explanation is omitted. Similarly, the function and position of the terminal TE that connects the second transparent electrode layer EL2 and the third transparent electrode layer EL3 via the wiring WR are the same as in the first embodiment, so the explanation is omitted. In this example, an example in which the first transparent electrode layer EL1 is divided into four parts is described, but the number of divisions and the direction of division can be set arbitrarily.

[0085] As explained above, the light-adjusting film 1 according to this modified example has a third transparent electrode layer EL3 located on the outside in the in-plane direction of the plurality of first transparent electrode layers EL1 and having the same reference potential as the second transparent electrode layer EL2, thereby suppressing electromagnetic noise radiated from the end face of the plurality of first transparent electrode layers EL1 on the side where the third transparent electrode layer EL3 is located.

[0086] (Second Embodiment) In the first embodiment, the case in which the signal applied to the electrode layer EL is a single-ended signal in which an AC voltage is applied to the first transparent electrode layer EL1 and the second transparent electrode layer EL2 has a potential of 0V, equal to GND, was described. However, a differential signal in which an AC voltage is also applied to the second transparent electrode layer EL2 may be applied to the electrode layer EL. The second embodiment in which a differential signal is applied to the electrode layer EL will be described below. Note that the description of components that are common to the first embodiment will be omitted.

[0087] An AC voltage is applied to two power supply units PS connected to the first transparent electrode layer EL1 and the second transparent electrode layer EL2 in this embodiment. More specifically, the first transparent electrode layer EL1 and the second transparent electrode layer EL2 are connected to a control device 120 via the power supply units PS, and an AC voltage is applied from each power supply unit PS under the control of the control device 120. Here, the AC voltage applied to the second transparent electrode layer EL2 is an AC voltage that is in the opposite phase to the AC voltage applied to the first transparent electrode layer EL1.

[0088] Figure 11 is a cross-sectional view of the light-adjusting film according to this embodiment in the Z-X plane. As shown in Figure 11, the light-adjusting film 1 according to the second embodiment further has a fourth transparent electrode layer EL4 on the outside in the in-plane direction of the second transparent electrode layer EL2.

[0089] (Fourth Transparent Electrode Layer) As shown in Figure 11, the dimming film 1 according to this embodiment has a fourth transparent electrode layer EL4 located on the outside of the second transparent electrode layer EL2 in the in-plane direction, separated by a gap t2 distance. Here, the method for forming the fourth transparent electrode layer EL4 is the same as that for the third transparent electrode layer EL3, so the explanation is omitted. The fourth transparent electrode layer EL4 is located on the outside of the second transparent electrode layer EL2 in the in-plane direction. The fourth transparent electrode layer EL4 is not connected to the second transparent electrode layer EL2. The fourth transparent electrode layer EL4 is formed on the Z1 direction surface of the second substrate BM2, similar to the second transparent electrode layer EL2. The in-plane width T7 of the fourth transparent electrode layer EL4 is, for example, 1 mm or more and 100 mm or less, preferably 5 mm or more and 50 mm or less, and more preferably 10 mm or more and 30 mm or less. The preferred thickness of the third transparent electrode layer EL3 is the same as the preferred thickness of the first transparent electrode layer EL1. Furthermore, the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 in this embodiment have a reference potential. Specifically, the first transparent electrode layer EL1 and the second transparent electrode layer EL2 in this embodiment are subjected to AC voltages that are in opposite phases to each other, and the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 have a potential of 0V, which is equal to GND. Since the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 are at the same potential, they may be electrically connected via wires or the like. The fourth transparent electrode layer EL4 in this embodiment is connected to a power supply unit PS4 that is connected to wiring WR, and the power supply unit PS4 and the power supply unit PS3 connected to the third transparent electrode layer EL3 are connected to GND via wiring WR. This makes it possible to suppress electromagnetic noise radiated from the edge of the second transparent electrode layer EL2 toward the outward direction in the in-plane direction of the dimming film 1. In this embodiment as well, a cover CV is set around the power supply unit PS located inside the liquid crystal layer LC and the wiring WR connected to the power supply unit PS. The description of the cover CV is the same as in the first embodiment and will be omitted. Furthermore, the shapes of the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 are not limited to shapes that surround the entire circumference of the first transparent electrode layer EL1 and the second transparent electrode layer EL2, but may be shapes that surround a part of the entire circumference of the first transparent electrode layer EL1 and the second transparent electrode layer EL2. The functions and shape examples of the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 are the same as in the first embodiment and will be omitted.

[0090] As described above, the dimming film 1 according to this embodiment has a third transparent electrode layer EL3 located outside the in-plane direction of the first transparent electrode layer EL1 and at the same potential as GND, and a fourth transparent electrode layer EL4 located outside the in-plane direction of the second transparent electrode layer EL2 and at the same potential as GND. As a result, even when the signal applied to the electrode layer EL is an operating signal, electromagnetic noise radiated from the dimming film 1 toward the outward direction in the in-plane direction can be suppressed.

[0091] (Effects) The dimming film 1 according to the first aspect of this disclosure includes a first transparent electrode layer, a second transparent electrode layer, a liquid crystal layer provided between the first transparent electrode layer and the second transparent electrode layer, and a third transparent electrode layer located outside the in-plane direction of the first transparent electrode layer and having a reference potential. According to this disclosure, when the dimming film 1 is in operation, electromagnetic noise radiated to the outside of the dimming film 1 can be suppressed.

[0092] The dimmable film 1 according to the second aspect of this disclosure is the dimmable film 1 according to the first aspect, wherein the third transparent electrode layer EL3 surrounds the entire circumference of the first transparent electrode layer EL1. According to this disclosure, electromagnetic noise radiated outward in the in-plane direction from the first transparent electrode layer EL1 can be suppressed.

[0093] A dimmable film 1 according to a third aspect of this disclosure is a dimmable film 1 according to the first aspect, wherein the third transparent electrode layer EL3 surrounds a portion of the entire circumference of the first transparent electrode layer EL1. According to this disclosure, compared to the second aspect, it is possible to suppress electromagnetic noise radiated outward in the in-plane direction from a portion of the edges of the first transparent electrode layer EL1 and to expand the region in which transmittance can be controlled.

[0094] The dimmable film 1 according to the fourth aspect of this disclosure is the dimmable film 1 described in any one of the first to third aspects, wherein the second transparent electrode layer EL2 is superimposed on both the first transparent electrode layer EL1 and the third transparent electrode layer EL3 when viewed from the lamination direction. According to this disclosure, when the dimmable film 1 is in operation, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed.

[0095] The dimmable film 1 according to the fifth aspect of this disclosure is the dimmable film 1 according to the fourth aspect, wherein an AC voltage is applied to the first transparent electrode layer EL1, and the potential of the second transparent electrode layer EL2 is the reference potential. According to this disclosure, when the dimmable film 1 is in operation, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed.

[0096] The dimmable film 1 according to the sixth aspect of this disclosure is the dimmable film 1 according to the fifth aspect, wherein the second transparent electrode layer EL2 is electrically connected to the third transparent electrode layer EL3. According to this disclosure, the potential difference between the second transparent electrode layer EL2 and the third transparent electrode layer EL3 can be eliminated.

[0097] The dimmable film 1 according to the seventh aspect of this disclosure is the dimmable film 1 according to the sixth aspect, wherein the second transparent electrode layer EL2 is electrically connected to the third transparent electrode layer EL3 at multiple locations. According to this disclosure, the potential difference between the second transparent electrode layer EL2 and the third transparent electrode layer EL3 can be made smaller compared to the sixth aspect.

[0098] The dimmable film 1 according to the eighth aspect of this disclosure is the dimmable film 1 described in any one of the first to seventh aspects, wherein the reference potential is a potential whose absolute value is smaller than the peak voltage value of the voltage applied to the first transparent electrode layer EL 1. According to this disclosure, even when the signal applied to the electrode layer EL is a single-ended signal, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed when the dimmable film 1 is in operation.

[0099] The dimmable film 1 according to the ninth aspect of this disclosure is the dimmable film 1 described in any one of the first to eighth aspects, wherein the reference potential is 0V. According to this disclosure, even when the signal applied to the electrode layer EL is a single-ended signal, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed when the dimmable film 1 is in operation.

[0100] A dimmable film 1 according to the tenth aspect of this disclosure is a dimmable film 1 according to any one of the first to ninth aspects, further comprising a fourth transparent electrode layer EL4 located outside the second transparent electrode layer EL2 in the in-plane direction and having a reference potential, and an AC voltage is applied to both the first transparent electrode layer EL1 and the second transparent electrode layer EL2. According to this disclosure, even when the signal applied to the electrode layer EL is a differential signal, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed when the dimmable film 1 is in operation.

[0101] The dimmable film 1 according to the eleventh aspect of this disclosure is the dimmable film 1 according to the tenth aspect, wherein the third transparent electrode layer EL3 is electrically connected to the fourth transparent electrode layer EL4. According to this disclosure, the potential difference between the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 can be eliminated.

[0102] The dimmable film 1 according to the twelfth aspect of this disclosure is the dimmable film 1 according to the tenth aspect, wherein at least one of the third transparent electrode layer EL3 and the fourth transparent electrode layer EL4 is electrically connected to the vehicle's ground. According to this disclosure, even when the signal applied to the electrode layer EL is a differential signal, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed when the dimmable film 1 is in operation.

[0103] A dimmable film 1 according to the thirteenth aspect of this disclosure is a dimmable film 1 according to any one of the first to tenth aspects, wherein the first transparent electrode layer EL1 is divided. According to this disclosure, even in a dimmable film 1 in which the transmittance can be controlled for each divided first transparent electrode layer EL1, electromagnetic noise radiated to the outside of the dimmable film 1 can be suppressed when the dimmable film 1 is in operation.

[0104] The laminated glass 100 according to the 14th aspect of this disclosure comprises a first glass plate GL1 and a second glass plate GL2, and a dimming film 1 according to any one of the first to 13 aspects provided between the first glass plate GL1 and the second glass plate GL2. According to this disclosure, electromagnetic noise radiated to the outside of the laminated glass can be suppressed.

[0105] Although embodiments of the present invention have been described above, the embodiments are not limited to those described herein. Furthermore, the aforementioned components include those that can be easily conceived by those skilled in the art, those that are substantially the same, and those that fall within the so-called equivalent range. Moreover, the aforementioned components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the embodiments described above.

[0106] 1 Dimming film 100 Laminated glass GL1 First glass plate GL2 Second glass plate IL Intermediate layer SH Shielding layer BM1 First substrate BM2 Second substrate EL1 First transparent electrode layer EL2 Second transparent electrode layer EL3 Third transparent electrode layer EL4 Fourth transparent electrode layer LC Liquid crystal layer The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2024-230837, filed on December 26, 2024, are incorporated herein by reference as disclosure of the specification of the present invention.

Claims

1. A light-adjusting film comprising: a first transparent electrode layer; a second transparent electrode layer; a liquid crystal layer provided between the first transparent electrode layer and the second transparent electrode layer; and a third transparent electrode layer located on the outside of the in-plane direction of the first transparent electrode layer and having a reference potential.

2. The dimmable film according to claim 1, wherein the third transparent electrode layer surrounds the entire circumference of the first transparent electrode layer.

3. The dimmable film according to claim 1, wherein the third transparent electrode layer surrounds a portion of the entire circumference of the first transparent electrode layer.

4. The light-adjusting film according to claim 1, wherein the in-plane width of the third transparent electrode layer is 1 mm or more and 300 mm or less.

5. The light-adjusting film according to claim 1, wherein the area of ​​the third transparent electrode layer is less than or equal to the area of ​​the first transparent electrode layer.

6. The light-adjusting film according to any one of claims 1 to 5, wherein the second transparent electrode layer is superimposed on both the first transparent electrode layer and the third transparent electrode layer when viewed from the stacking direction.

7. The light-adjustable film according to claim 6, wherein an AC voltage is applied to the first transparent electrode layer and the potential of the second transparent electrode layer is the reference potential.

8. The dimmable film according to claim 7, wherein the second transparent electrode layer is electrically connected to the third transparent electrode layer.

9. The dimmable film according to claim 8, wherein the second transparent electrode layer is electrically connected to the third transparent electrode layer at multiple locations.

10. The light-adjustable film according to any one of claims 1 to 5, wherein the reference potential is a potential whose absolute value is smaller than the peak voltage value of the voltage applied to the first transparent electrode layer.

11. The light-adjusting film according to any one of claims 1 to 5, wherein the reference potential is 0V.

12. The dimmable film according to any one of claims 1 to 5, further comprising a fourth transparent electrode layer located outside the in-plane direction of the second transparent electrode layer and having the reference potential, wherein an AC voltage is applied to both the first transparent electrode layer and the second transparent electrode layer.

13. The dimmable film according to claim 12, wherein the third transparent electrode layer is electrically connected to the fourth transparent electrode layer.

14. The dimming film according to claim 12, wherein at least one of the third transparent electrode layer and the fourth transparent electrode layer is electrically connected to the vehicle's ground.

15. The light-adjustable film according to any one of claims 1 to 5, wherein the first transparent electrode layer is divided.

16. Laminated glass comprising a first glass plate and a second glass plate, and a light-adjusting film according to any one of claims 1 to 5 provided between the first glass plate and the second glass plate.

17. The laminated glass according to claim 16, having a band-shaped shielding layer along its periphery, wherein the third transparent electrode layer is positioned so that, in a plan view, its entire area overlaps with the shielding layer.

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