Electrochromic device and method for manufacturing the same

Abstract

To provide an electrochromic device that achieves high-level reliability and low cost while improving responsiveness.SOLUTION: A method for manufacturing an electrochromic device includes adjusting an electrochromic gel 3 including a cross-linked body of a dimer or more polymer of a compound having tertiary amine or cyclic imine on the side chain, arranging the electrochromic gel 3 on a first electrode 2a formed with a seal pattern 4 and subsequently reducing the pressure inside the seal pattern 4, and pasting the first electrode 2a and a second electrode 2b to each other to obtain an electrochromic device.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electrochromic device and a method for manufacturing the same. [Background technology]

[0002] An electrochromic (hereinafter sometimes referred to as "EC") element is an active optical element that has a pair of electrodes and an EC layer disposed between the electrodes. It adjusts the hue and light intensity in the visible light range by applying a voltage between the pair of electrodes and oxidizing or reducing the compounds in the EC layer. EC elements are already widely used in anti-glare mirrors in automobiles and dimming windows in aircraft, but to further popularize them as consumer products, it is necessary to adopt simpler configurations and manufacturing methods and to provide them at lower costs.In addition, in recent years, there have been increasing opportunities to combine photochromic elements with wearable device terminals such as watches and glasses, and high reliability is also required for the photochromic elements that function on these terminals. The vacuum lamination method, which has been widely used in recent years as a method for manufacturing EC elements, is an element manufacturing method that requires fewer steps than the conventional vacuum injection method, and is often adopted because it is advantageous for manufacturing large areas and can handle high-viscosity solutions. Patent Document 1 discloses a technology for avoiding display defects such as drip marks and filling unevenness caused by solvent evaporation in a manufacturing method by vacuum lamination of display panels that use EC elements or electrodeposition (hereinafter referred to as "ED") elements, by reducing the surface area where the dripped solution comes into contact with the vacuum atmosphere. Furthermore, in order to achieve high reliability, the EC layer is gelled, semi-solidified, or solidified to prevent solution leakage when the device is broken. Patent Document 2 discloses a technique in which an electrochromic gelling medium is filled into the device by vacuum injection, and then a crosslinking reaction is carried out to gel or form a film. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2011 / 018916 Brochure [Patent Document 2] Japanese Patent Application Publication No. 2019-91053 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the manufacturing method disclosed in Patent Document 1 is a technology for fabricating devices by vacuum laminating EC media that do not gel, and therefore does not address new challenges in device processing and device performance that arise from gelling agents. Furthermore, the technology disclosed in Patent Document 2 is limited to vacuum injection as a device fabrication method, and the EC gel is formed in a polymer medium by cross-linking polymerization of an EC compound having two or more hydroxyl groups at its terminals with a compound having two or more isocyanate groups, and the EC molecules are arranged in a branched form in the polymer network, making mass transfer difficult and leaving room for improvement in responsiveness. In view of the above problems, an object of the present invention is to provide an electrochromic element which has improved response while realizing high reliability and low cost. [Means for solving the problem]

[0005] A first aspect of the present invention is an electrochromic device having a first electrode, a second electrode, and an electrochromic layer containing at least one electrochromic compound disposed between the first electrode and the second electrode, The electrochromic layer is characterized in that it is a gel layer containing a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or a cyclic imine in the side chain. A second aspect of the present invention is a method for producing an electrochromic device having a first electrode, a second electrode, and an electrochromic layer containing at least one electrochromic compound disposed between the first electrode and the second electrode, the method comprising: an electrochromic gel preparation step of preparing an electrochromic gel containing at least one electrochromic compound, a solvent, and a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or cyclic imine in a side chain; a seal pattern forming step of forming a seal pattern on the first electrode to be filled with the electrochromic gel; a decompression step of decompressing the inside of the seal pattern after disposing the electrochromic gel in a region surrounded by the seal pattern on the first electrode; a bonding step of bonding the first electrode and the second electrode together under reduced pressure; The present invention is characterized by having the following. [Effects of the Invention]

[0006] According to the present invention, by fabricating an EC element using a vacuum bonding method, which uses an EC layer made of an ionic chemical gel, it is possible to realize an EC element with high display quality that combines high reliability and responsiveness using a simple manufacturing method, thereby providing a light control element, a light control film, a light control window, and the like that are excellent in device performance and cost performance. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view showing an embodiment of an EC element of the present invention. [Figure 2] 1A to 1C are cross-sectional views showing a method for producing an EC element by a vacuum bonding method according to the present invention. [Figure 3] FIG. 1 shows the change in rotational torque during the gelation process of an EC gel. [Figure 4] 1 is a schematic diagram illustrating an example of a driving device including an EC element according to an embodiment of the present invention. [Figure 5] 1A and 1B are schematic diagrams illustrating an example of an imaging device in which an optical filter is disposed in a lens unit and an imaging device, respectively; [Figure 6]1A is a schematic view showing a window using an EC element according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view in the thickness direction of a window using an EC element according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, the configuration of an electrochromic element (EC element) according to the present invention will be described in detail by way of example of a preferred embodiment with reference to the drawings. However, unless otherwise specified, the configuration, relative arrangement, etc. described in this embodiment are not intended to limit the scope of the present invention.

[0009] (EC element) First, the structure of the EC element of the present invention will be described with reference to Figure 1. Figure 1 is a cross-sectional schematic diagram of one embodiment of the EC element of the present invention in the thickness direction. In Figure 1, 1a and 1b are first and second substrates, respectively, and first and second electrodes 2a and 2b are formed on one side of the substrates (inside the element), respectively. 3 is an electrochromic layer (EC layer), and 4 bonds the first substrate 1a and the second substrate 1b and also plays a role in protecting the EC layer 3 from the ambient environment (oxygen, water).

[0010] The first and second substrates 1a and 1b are required to be made of an electrical insulator such as glass or resin, which is highly transparent, has excellent heat resistance, and is highly chemically stable. Examples of glass that can be used include optical glass, quartz glass, white plate glass, blue plate glass, borosilicate glass, alkali-free glass, and chemically strengthened glass. In particular, alkali-free glass is preferred for its transparency and durability. Examples of resins that can be used include polycarbonate (PC), acrylic (PMMA), polyethylene terephthalate (PET), and transparent polyimide (PI). Furthermore, these resins can be preferably provided with a hard coat layer on their surfaces to improve scratch resistance.

[0011] The first and second electrodes 2a and 2b are both transparent electrodes, and examples of the material include indium tin oxide (ITO), fluorine-doped tin oxide (FTO), tin oxide (NESA), indium zinc oxide (IZO), graphene, etc. Conductive polymers whose conductivity has been improved by doping or the like, such as polyaniline, polypyrrole, polythiophene, polyacetylene, polyparaphenylene, and a complex of polyethylenedioxythiophene (PEDOT) and polystyrene sulfonic acid, are also suitable.

[0012] The EC layer 3 is a gel layer made of an electrochromic gel (EC gel) containing an organic solvent in which an electrochromic compound (EC compound) is dissolved, in order to ensure the reliability of the EC element.

[0013] The EC compound is preferably an organic compound, and may be either an anodic compound that changes color from a transparent state by an oxidation reaction, or a cathodic compound that changes color from a transparent state by a reduction reaction. Both an anodic compound and a cathodic compound may be used. Using both an anodic compound and a cathodic compound is preferable because it increases the coloring efficiency with respect to current. In this specification, a device having both an anodic compound and a cathodic compound is referred to as a complementary EC device. An anodic compound is also referred to as an anode material, and a cathodic compound is also referred to as a cathode material.

[0014] When a complementary EC element is operated, electrons are extracted from the EC compound at one electrode through an oxidation reaction, and electrons are received by the EC compound at the other electrode through a reduction reaction. Radical cations may be generated from neutral molecules through an oxidation reaction. Radical anions may also be generated from neutral molecules through a reduction reaction, or radical cations may be generated from dicationic molecules. Because the EC compound is colored at both electrodes 2a and 2b, a complementary EC element is preferable when a large change in optical density is required during coloration.

[0015] Examples of the organic EC compound include conductive polymers such as polythiophene and polyaniline, viologen compounds, anthraquinone compounds, oligothiophene derivatives, and organic low molecular weight compounds such as phenazine derivatives.

[0016] The EC layer 3 preferably contains at least one anodic EC compound or one cathodic EC compound so as to form a complementary EC element.

[0017] When the EC layer 3 contains multiple EC compounds, it is preferable that the difference in redox potential between the EC compounds is small. When multiple EC compounds are contained, the anodic and cathodic compounds may be a total of four or more EC compounds. In the present invention, five or more EC compounds may be contained. When multiple EC compounds are contained, the redox potentials of the multiple anodic materials are preferably within 60 mV, and the redox potentials of the multiple cathodic materials are preferably within 60 mV. When multiple EC compounds are contained, it is preferable that the multiple EC compounds include a compound having an absorption peak from 400 nm to 500 nm, a compound having an absorption peak from 500 nm to 650 nm, and a compound having an absorption peak above 650 nm. The absorption peak refers to a peak with a half-width of 20 nm or more. Furthermore, the state of the material when absorbing light may be oxidized, reduced, or neutral.

[0018] The EC layer 3 may contain an electrolyte. The electrolyte is not limited as long as it is an ion-dissociating salt that has good solubility in a solvent and high compatibility with a solid electrolyte. Among these, an electrolyte having electron-donating properties is preferable. These electrolytes can also be called supporting electrolytes. Examples of the electrolyte include inorganic ion salts such as various alkali metal salts and alkaline earth metal salts, quaternary ammonium salts, and cyclic quaternary ammonium salts. Specific examples include alkali metal salts of Li, Na, and K, such as LiClO4, LiSCN, LiBF4, LiAsF6, LiCF3SO3, LiPF6, LiI, NaI, NaSCN, NaClO4, NaBF4, NaAsF6, KSCN, and KCl, as well as quaternary ammonium salts and cyclic quaternary ammonium salts, such as (CH3)4NBF4, (C2H5)4NBF4, (n-C4H9)4NBF4, (n-C4H9)4NPF6, (C2H5)4NBr, (C2H5)4NClO4, and (n-C4H9)4NClO4.

[0019] The solvent for dissolving the EC compound and the electrolyte is not particularly limited as long as it can dissolve the EC compound and the electrolyte, but particularly polar solvents are preferred. Specific examples include water and organic polar solvents such as methanol, ethanol, propylene carbonate, ethylene carbonate, dimethyl sulfoxide, dimethoxyethane, γ-butyrolactone, γ-valerolactone, sulfolane, dimethylformamide, dimethoxyethane, tetrahydrofuran, acetonitrile, propionitrile, 3-methoxypropionitrile, benzonitrile, dimethylacetamide, methylpyrrolidinone, and dioxolane.

[0020] The EC layer 3 may also have spacers that define the distance between the first and second electrodes 2 a and 2 b. The spacers may be made of inorganic materials such as silica beads and glass fibers, or organic materials such as polydivinylbenzene, polyimide, polytetrafluoroethylene, fluororubber, and epoxy resin.

[0021] The EC layer 3 according to the present invention is a gel layer containing a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or a cyclic imine in its side chain. Examples of polymers of compounds having a tertiary amine in their side chains include poly(dimethylaminoethyl methacrylate), and examples of polymers of compounds having a cyclic imine in their side chains include poly(4-vinylpyridine). However, the present invention is not limited to these. In addition to the above polymers, polyacrylonitrile, carboxymethyl cellulose, pullulan-based polymers, polyvinyl chloride, polyethylene oxide, polypropylene oxide, polyurethane, polyacrylate, polymethacrylate, polyamide, polyacrylamide, polyester, polyvinylpyridine, Nafion (registered trademark), and the like may also be used.

[0022] As a cross-linking agent for cross-linking the polymer, a compound having two or more electrophilic substituents, such as N,N,N',N'-tetra(trifluoromethanesulfonyl)-hexane-1,6-diamine or N,N,N',N'-tetra(trifluoromethanesulfonyl)-dodecane-1,12-diamine, can be suitably used. By using the specific polymer and cross-linking agent, the EC layer 3 can be made into an ionic chemical gel, which is more reliable than a physical gel that liquefies above its transition temperature, and it is possible to fabricate an EC element with good responsiveness.

[0023] The seal 4 preferably connects the first and second substrates 1a and 1b, on which the first and second electrodes 2a and 2b are formed, and protects the EC layer 3 from the ambient environment (oxygen, water). Furthermore, since it comes into direct contact with the electrochemically active EC layer 3, it must be non-reactive with the EC compound and have low affinity with the solvent that dissolves the EC compound. Therefore, one-component, solventless acrylic resins, epoxy resins, etc., are preferably used as the seal 4. The seal may be made of a single material, or multiple materials with separate functions may be used in a multi-layer structure.

[0024] Furthermore, bus wiring (not shown) may be provided around the outer periphery of the seal 4 to ensure uniform voltage application across the entire dimming region. The bus wiring is preferably made of a low-resistance metal material, such as a thin film of silver, palladium, copper, aluminum, a silver-palladium-copper alloy (APC), or an aluminum-neodymium alloy. The bus wiring is preferably formed on a pair of transparent electrodes so as to surround the dimming region, and multiple power supply points may be provided for each bus wiring to prevent voltage drops within the bus wiring.

[0025] (Method for manufacturing EC element) Next, a method for producing an EC element of the present invention will be described with reference to Fig. 2. Fig. 2 is a cross-sectional view in the thickness direction showing the steps for producing the EC element exemplified in Fig. 1. The EC element of the present invention can be preferably produced by vacuum lamination. Figure 2 is a diagram showing a method for producing an EC element by vacuum lamination according to the present invention.

[0026] (1) EC gel preparation step: An EC gel containing at least one EC compound, a solvent, and a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or cyclic imine in the side chain is prepared. The EC gel is obtained by heating an EC gelling solution containing an electrochromic compound, a solvent, a dimer or higher of a compound having a tertiary amine or cyclic imine in the side chain, and a crosslinker. The heating temperature and heating time for gelling the EC gelling solution are appropriately selected depending on the types of EC compound, solvent, polymer, and crosslinker used, and the degree of gelling.

[0027] (2) Seal pattern formation process: A seal 4 surrounding the dimming region is drawn and formed on the first substrate 1a on which the first electrode 2a has been formed, using a dispenser or the like (FIG. 2(a)). (3) Decompression step: The electrode substrate (lower) prepared in (2) above and its mating electrode substrate (upper) are placed in a vacuum lamination device, and an appropriate amount of pre-gelled EC gel 3 is taken and placed on the lower electrode substrate. After reducing the pressure inside the vacuum chamber 6 to approximately 100 Pa (Figure 2(b)), the upper and lower electrode substrates are brought close to the distance specified by the spacer and then irradiated with UV light to harden the seal. At this time, it is preferable to install a shielding mask to prevent the gel layer from being exposed to UV light.

[0028] (4) Completion of bonding: The chamber 6 is vented with nitrogen gas or dry air (Fig. 2(c)), and the EC element is removed. If a seal that requires additional curing by heat is used, it is subsequently heated in an oven. Finally, a pair of terminals corresponding to the pair of electrodes 2a, 2b is connected, and the EC element is completed.

[0029] Here, the EC gel is pre-gelled and placed on the electrode 2a before bonding, but depending on the degree of gelling of the EC gel, display defects such as drip marks and deterioration of characteristics may occur, so particular care is required. Therefore, we quantified the degree of gelling of the EC gel and considered the causes of display defects.

[0030] Figure 3 shows the quantification of the gelation process of EC gel at 90°C by rotational torque using an automated gelation time method A device according to JIS K6910:2007. This shows that gelation of EC gel begins after approximately 5 minutes at 90°C, and gelation is nearly complete after approximately 30 minutes, when the rotational torque reaches 900 mgf·cm to 1000 mgf·cm. We therefore prepared EC gels with varying degrees of gelation depending on the heating time, and fabricated EC devices from these using the vacuum bonding method described above. We then evaluated their characteristics. Devices fabricated from gels with little progress in gelation exhibited significant display defects and performance degradation, while devices with more advanced gelation (rotational torque of 500 mgf·cm or higher) showed improvements in display defects and performance degradation.

[0031] Furthermore, because display defects and performance degradation were particularly pronounced when the electrodes 2a and 2b of the EC device had hydrophilic surfaces, it is inferred that the polymer of a compound with a tertiary amine or cyclic imine side chain in the EC gelling solution adsorbs or coordinates to the electrode surface, inhibiting the EC reaction. Therefore, it can be said that EC gels used in the vacuum bonding method should preferably have a rotational torque of 500 mgf cm or more when measured using an automated gelation time method A device according to JIS K6910:2007.

[0032] (Applications of EC elements) The EC device according to the present invention can be used in optical filters, lens units, imaging devices, window materials, and the like. <Optical filters> The optical filter according to this embodiment includes an EC element and an active element connected to the EC element. The active element drives the EC element and adjusts the amount of light passing through the EC element. Examples of the active element include a transistor. The transistor may have an oxide semiconductor such as InGaZnO in its active region.

[0033] The optical filter according to this embodiment includes an EC element according to the present invention and a driver connected to the EC element. Fig. 4 is a schematic diagram showing an example of a driver 20 for the EC element and an EC element 5 driven by the driver 20. The driver 20 according to this embodiment includes a drive power supply 8, a resistor switch 9, and a controller 10.

[0034] The driving power supply 8 applies to the EC element 5 a voltage necessary for the EC material contained in the EC layer to undergo an electrochemical reaction. A constant driving voltage is preferable. This is because, when the EC material is composed of multiple types of materials, the absorption spectrum may change due to differences in the redox potentials or molar absorption coefficients of the materials. The driving power supply 8 starts applying voltage or maintains the applied state in response to a signal from the controller 10. The constant voltage is maintained during the period when the light transmittance of the EC element 5 is being controlled.

[0035] The controller 10 controls the transmittance of the EC element 5 in a manner appropriate for the EC element 5 being used. Specifically, this can involve inputting predefined conditions into the EC element 5 for a desired transmittance setting, or comparing the transmittance setting with the transmittance of the EC element 5 and selecting and inputting conditions that match the setting. Examples of parameters that can be varied include voltage, current, and duty ratio. The controller 10 can change the color density of the EC element 5 by varying the voltage, current, or duty ratio.

[0036] In this embodiment, known means can be used to change the voltage, change the current, and modulate the pulse width. The pulse width can also be modulated as follows.

[0037] The resistance switch 9 switches between a resistor R1 (not shown) and a resistor R2 (larger than R1) in series in a closed circuit including the drive power supply 8 and the EC element 5. The resistance value of resistor R1 is preferably smaller than the largest impedance in the closed circuit, and is preferably 10 Ω or less. The resistance value of resistor R2 is preferably larger than the largest impedance in the closed circuit, and is preferably 1 MΩ or greater. Resistor R2 may be air. In this case, strictly speaking, the closed circuit becomes an open circuit, but it can be considered a closed circuit by regarding the air as resistor R2. The controller 10 sends a switching signal to the resistor switch 9 to control the switching of the resistors R1 and R2, but the PWM signal may be generated using a comparator or the like without using a resistor switch.

[0038] <Lens unit> The lens unit according to this embodiment includes an imaging optical system having a plurality of lenses and an optical filter having an EC element according to the present invention. The optical filter may be provided either between the lenses or outside the lenses. The optical filter is preferably provided on the optical axis of the lenses.

[0039] <Imaging device> The imaging device of this embodiment has an optical filter and a light-receiving element that receives light that has passed through the optical filter. Specific examples of imaging devices include cameras, video cameras, and mobile phones with cameras. The imaging device may have a configuration in which a main body having a light-receiving element and a lens unit having a lens can be separated. Here, if the imaging device can be separated into a main body and a lens unit, the present invention also includes a configuration in which an optical filter separate from the imaging device is used during imaging. In such cases, the optical filter may be located outside the lens unit, between the lens unit and the light-receiving element, or between multiple lenses (if the lens unit has multiple lenses).

[0040] FIG. 5(a) is a schematic diagram of an example of an imaging device in which an optical filter is arranged in a lens unit, and FIG. 5(b) is a schematic diagram of an example of an imaging device in which an optical filter is arranged in the imaging device.

[0041] The imaging device 40 includes a lens unit 42 and an imaging unit 43. The lens unit 42 includes an optical filter 41 and an imaging optical system including a plurality of lenses or a lens group. The optical filter 41 is the optical filter of the present embodiment described above.

[0042] 5(a), the lens unit 42 represents, for example, a rear-focusing zoom lens in which focusing is performed after the aperture. It has four lens groups, in order from the object side: a first lens group 44 with positive refractive power, a second lens group 45 with negative refractive power, a third lens group 46 with positive refractive power, and a fourth lens group 47 with positive refractive power. Magnification is changed by changing the distance between the second lens group 45 and the third lens group 46, and focusing is performed by moving some of the lens groups in the fourth lens group 47.

[0043] The lens unit 42 has, for example, an aperture diaphragm 48 between the second lens group 45 and the third lens group 46, and an optical filter 41 between the third lens group 46 and the fourth lens group 47. The lens unit is arranged so that light passing through the lens group 44 to 47 passes through the aperture diaphragm 48 and the optical filter 41, and the amount of light can be adjusted using the aperture diaphragm 48 and the optical filter 41. The lens unit 42 is detachably connected to the imaging unit 43 via a mount member (not shown).

[0044] In this embodiment, the optical filter 41 is disposed between the third lens group 46 and the fourth lens group 47 in the lens unit 42, but the imaging device 40 is not limited to this configuration. For example, the optical filter 41 may be disposed either in front of (on the subject side) or behind (on the imaging unit 43 side) the aperture stop 48, or may be disposed in front of, behind, or between any of the first to fourth lens groups 44 to 47. Disposing the optical filter 41 at a position where light converges has the advantage of making it possible to reduce the area of ​​the optical filter 41.

[0045] The configuration of the lens unit 42 is not limited to the above configuration and can be selected as appropriate. For example, in addition to a rear-focusing type, it may be an inner-focusing type in which focusing is performed in front of the aperture, or any other type. Furthermore, special lenses such as a fisheye lens or a macro lens can be selected as appropriate in addition to a zoom lens.

[0046] The imaging unit 43 has a glass block 49 and a light receiving element 50. The glass block 49 is a glass block that includes a low-pass filter, a face plate, a color filter, etc. The light receiving element 50 is a sensor unit that receives light that has passed through the lens unit, and an imaging element such as a CCD or CMOS can be used. Alternatively, an optical sensor such as a photodiode can be used, and any device that acquires and outputs information on the intensity or wavelength of light can be used as appropriate.

[0047] 5(a), when the optical filter 41 is incorporated into the lens unit 42, the driving device may be disposed inside or outside the lens unit 42. When disposed outside the lens unit 42, the EC element in the lens unit 42 is connected to the driving device via wiring to control driving.

[0048] Furthermore, in the configuration of the imaging device 40 described above, the optical filter 41 is disposed inside the lens unit 42. However, the present invention is not limited to this configuration, and it is sufficient that the optical filter 41 is disposed in an appropriate location inside the imaging device 40, and the light receiving element 50 is disposed so as to receive light that has passed through the optical filter 41.

[0049] For example, as shown in Fig. 5(b), the imaging unit 43 may have an optical filter 41. Fig. 5(b) is a diagram for explaining the configuration of another example of the imaging device of this embodiment, and is a schematic diagram of the configuration of an imaging device having the optical filter 41 in the imaging unit 43. In Fig. 5(b), for example, the optical filter 41 is arranged immediately before the light receiving element 50. When the imaging device itself has the optical filter 41 built in, the connected lens unit 42 itself does not need to have the optical filter 41, and therefore it is possible to configure a dimmable imaging device using an existing lens unit 42.

[0050] The imaging device 40 of this embodiment can be applied to products that combine light intensity adjustment and a light receiving element, such as cameras, digital cameras, video cameras, and digital video cameras, as well as to products with built-in imaging devices, such as mobile phones, smartphones, PCs, and tablets.

[0051] According to the imaging device 40 of this embodiment, by using the optical filter 41 as a dimming component, it is possible to appropriately change the amount of dimming with a single filter, which has the advantages of reducing the number of components and saving space.

[0052] <Window> The window according to this embodiment includes an EC element and an active element connected to the EC element. The active element drives the EC element and adjusts the amount of light passing through the EC element. Examples of the active element include a transistor. The transistor may have an oxide semiconductor such as InGaZnO in its active region. The window according to this embodiment may also be called a variable transmittance window.

[0053] Fig. 6(a) is a schematic diagram showing a light control window as a window material using the EC element of the present invention, and Fig. 6(b) is a cross-sectional view in the thickness direction at the center (A-A') of Fig. 6(a). The light control window of this embodiment comprises an EC element 5, transparent plates 61a and 61b that sandwich the EC element 5, and a frame 62 that surrounds and integrates the entire EC element 5. The EC element 5 of this embodiment has the configuration shown in Fig. 1 and includes a drive unit (not shown). The drive unit may be integrated within the frame 62, or may be located outside the frame 62 and connected to the EC element 5 via wiring.

[0054] The transparent plates 61a and 61b are not particularly limited as long as they are made of a material with high light transmittance, but a glass material is preferable considering use as a window. The frame 62 may be made of any material, but any material that covers at least a portion of the EC element 5 and has an integrated form may be considered a frame. In Figure 6, the EC element 5 is a component independent of the transparent plates 61a and 61b, but for example, the substrates 1a and 1b of the EC element 5 may be considered to be the transparent plates 61a and 61b.

[0055] Such a light-control window can be used, for example, to adjust the amount of sunlight entering a room during the day. Since it can be used to adjust not only the amount of sunlight but also the amount of heat, it can be used to control the brightness and temperature inside a room. It can also be used as a shutter to block views from the outside into the room. In addition to glass windows for buildings, such light-control windows can also be used as windows for vehicles such as automobiles, trains, airplanes, and ships. In this way, the EC element of the present invention can be used in optical filters, lens units, imaging devices, window materials, and the like.

[0056] Furthermore, by providing a reflective member on one of the light paths of the EC element, it can be made into an electrochromic mirror. EC mirrors may be installed in automobiles as anti-glare mirrors. EC mirrors can be configured by having an EC element and a reflective member disposed inside or outside the EC element. "Having a reflective member inside" means that the electrodes of the EC element are reflective. "Having a reflective member outside" means that a reflective member is provided in contact with the electrodes of the EC element or via another transparent member.

[0057] [Included components] The disclosure of this embodiment includes the following configuration. (Configuration 1) An electrochromic device having a first electrode, a second electrode, and an electrochromic layer comprising at least one electrochromic compound disposed between the first electrode and the second electrode, 1. An electrochromic element, wherein the electrochromic layer is a gel layer containing a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or a cyclic imine in the side chain. (Configuration 2) 2. The electrochromic element according to claim 1, wherein the electrochromic layer has a rotational torque of 500 mgf·cm or more when measured using an automated gel time method A according to JIS K6910:2007. (Configuration 3) 3. The electrochromic element according to claim 1, wherein the electrochromic layer contains a plurality of electrochromic compounds. (Configuration 4) 4. The electrochromic device of claim 3, wherein the plurality of electrochromic compounds includes an anodic electrochromic compound and a cathodic electrochromic compound. (Configuration 5) 5. The electrochromic device according to any one of configurations 1 to 4, wherein the polymer is poly(4-vinylpyridine) or poly(dimethylaminoethyl methacrylate).

[0058] (Configuration 6) 1. A method for manufacturing an electrochromic device having a first electrode, a second electrode, and an electrochromic layer including at least one electrochromic compound disposed between the first electrode and the second electrode, comprising: an electrochromic gel preparation step of preparing an electrochromic gel containing at least one electrochromic compound, a solvent, and a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or cyclic imine in a side chain; a seal pattern forming step of forming a seal pattern on the first electrode to be filled with the electrochromic gel; a decompression step of decompressing the inside of the seal pattern after disposing the electrochromic gel in a region surrounded by the seal pattern on the first electrode; a bonding step of bonding the first electrode and the second electrode together under reduced pressure; A method for manufacturing an electrochromic element, comprising: (Configuration 7) The method for manufacturing an electrochromic element according to configuration 6, wherein the electrochromic gel has a rotational torque of 500 mgf cm or more when measured using an automated device for gelation time method A according to JIS K6910:2007. (Configuration 8) The method for manufacturing an electrochromic element according to Configuration 6 or 7, wherein the electrochromic gel is gelled by heating an electrochromic gelling solution containing the electrochromic compound, the solvent, a polymer of dimer or higher of a compound having the tertiary amine or cyclic imine in a side chain, and a crosslinking agent. (Configuration 9) 9. The method for producing an electrochromic element according to any one of configurations 6 to 8, wherein the electrochromic compound is of a plurality of types. (Configuration 10) The method for manufacturing an electrochromic device according to Configuration 9, wherein the plurality of electrochromic compounds include an anodic electrochromic compound and a cathodic electrochromic compound. (Configuration 11) The electrochromic device according to any one of Configurations 6 to 10, wherein the polymer is poly(4-vinylpyridine) or poly(dimethylaminoethyl methacrylate).

[0059] (Configuration 12) An optical filter comprising the electrochromic device according to any one of Configurations 1 to 5 and a transistor connected to the electrochromic device. (Configuration 13) A lens unit comprising the optical filter according to Configuration 12 and an imaging optical system having a plurality of lenses. (Configuration 14) An imaging device comprising the optical filter according to Configuration 12 and a light receiving element that receives light that has passed through the optical filter. (Configuration 15) A window material comprising the electrochromic device according to any one of Configurations 1 to 5 and a transistor connected to the electrochromic device. (Configuration 16) An electrochromic mirror comprising the electrochromic device according to any one of Configurations 1 to 5 and a reflecting member disposed inside or outside the electrochromic device.

Examples

[0060] (Example 1) <EC gel preparation> The four EC compounds listed below were dissolved in propylene carbonate solvent, followed by the addition of 50 μm diameter gap-controlling particles (Micropearl SP250, manufactured by Sekisui Chemical Co., Ltd.). Next, poly(4-vinylpyridine) was added as a polymer of a compound with a cyclic imine side chain, and N,N,N',N'-tetra(trifluoromethanesulfonyl)-hexane-1,6-diamine, which has two or more electrophilic substituents, was added as a crosslinker. The mixture was heated to 90°C for approximately 15 minutes to promote gelation. The rotational torque of the resulting EC gel was measured using an automated gelation time method A (Madoka, manufactured by Cyber) according to JIS K6910:2007, and was characterized as 572 mgf·cm.

[0061] [Anodic EC Compounds] 3-(2-isoproxy-6-methoxyphenyl)-1,5,10-trimethyl-8-phenoxy-5,10-dihydrophenazine 5,10-Diisopropyl-2-(3-methoxyphenoxy)-7-methyl-5,10-dihydrophenazine [Cathodic EC Compounds] 9,9-Dimethyl-2,7-bis(4,4,4-trifluorobutyl)-9H-cyclopenta[1,2-c:4,3-c']dipyridinium bis[bis(trifluoromethanesulfonyl)imide] 1,1'-bis(4-tert-butyl)phenyl-3-methyl-4,4'-dipyridinium bis[bis(trifluoromethanesulfonyl)imide]

[0062] <Element fabrication> A UV-curable acrylic seal (ThreeBond "3035B") was applied to an ITO glass substrate with a sheet resistance of 10 Ω / □ using a dispenser in a shape that surrounded the rectangular dimming area. The ITO glass substrate with the sticker pattern and a mating ITO glass substrate of the same specifications were placed in a vacuum lamination device, and an appropriate amount of the above EC gel was placed in the light control area of ​​the ITO glass substrate with the sticker pattern (bottom). After evacuating the vacuum lamination device to 100 Pa, the pair of ITO glass substrates were laminated together and irradiated with UV light to harden the seal. The device was removed from the vacuum lamination device, and a pair of terminals corresponding to the pair of ITO electrodes was connected to complete the EC device.

[0063] Example 2 An EC gel was prepared in the same manner as in Example 1, except that the heating time of the EC gelling solution was extended to approximately 30 minutes. The rotational torque of the obtained EC gel was characterized as 880 mgf cm. An EC device was fabricated using this EC gel in the same manner as in Example 1.

[0064] Example 3 An EC gel was prepared by heating at 90°C for approximately 30 minutes in the same manner as in Example 1, except that poly(dimethylaminoethyl methacrylate) was used as the polymer of the compound having a tertiary amine in the side chain and N,N,N',N'-tetra(trifluoromethanesulfonyl)-dodecane-1,12-diamine, which has two or more electrophilic substituents, was used as the crosslinker. The rotational torque of the obtained EC gel was characterized as 512 mgf cm. An EC device was fabricated using this EC gel in the same manner as in Example 1.

[0065] (Comparative Example 1) An EC gelling solution with the same specifications as in Example 1 was used, but without gelling before vacuum lamination, vacuum lamination was performed in the solution state, and the formed element was heated at 90°C for 60 minutes. The other conditions were the same as in Example 1 to produce an EC element.

[0066] (Comparative Example 2) An EC gel was prepared in the same manner as in Example 1, except that gelation was suppressed by shortening the heating time of the EC gelling solution to approximately 6 minutes. The rotational torque of the obtained EC gel was characterized as 176 mgf cm. An EC device was fabricated using this EC gel in the same manner as in Example 1.

[0067] (Element evaluation) The electrical and optical characteristics, as well as the display quality, were evaluated for each of the EC devices of Examples 1 to 3 and Comparative Examples 1 and 2. The results are shown in Table 1. The electrical and optical characteristics were evaluated by comparing the current density and optical density when 0.7 V was applied, and the display quality was evaluated by whether or not unevenness could be distinguished within the optical density range of 0 to 0.3 (approximately 1 level).

[0068] From Comparative Examples 1 and 2 and Examples 1 and 2, it was found that when the EC gel before vacuum lamination was insufficiently gelled and in a liquid state, both the current and optical density were small and unevenness in display quality was noticeable, but when it was sufficiently gelled, both the current and optical density were large and a uniform display could be achieved within the surface. In other words, when the EC gel was measured using an automated device based on gelation time method A according to JIS K6910:2007, as long as the rotational torque was 500 mgf cm or more, there was no display defect or deterioration in characteristics. Furthermore, as shown in Example 3, even if the polymer and crosslinking agent were changed, no display defects or deterioration of characteristics occurred within the above range of rotational torque.

[0069] [Table 1]

[0070] In Table 1, the polymers and crosslinking agents are as follows: P4VP: Poly(4-vinylpyridine) PDMEMA: Poly(dimethylaminoethyl methacrylate) C6TFSA: N,N,N',N'-tetra(trifluoromethanesulfonyl)-hexane-1,6-diamine C12TFSA: N,N,N',N'-tetra(trifluoromethanesulfonyl)-dodecane-1,12-diamine [Explanation of symbols]

[0071] 2a, 2b: electrodes, 3: electrochromic layer, 4: seal, 5: electrochromic element, 40: imaging device, 41: optical filter, 50: light receiving element

Claims

1. An electrochromic device having a first electrode, a second electrode, and an electrochromic layer comprising at least one electrochromic compound disposed between the first electrode and the second electrode, 1. An electrochromic element, wherein the electrochromic layer is a gel layer containing a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or a cyclic imine in the side chain.

2. 2. The electrochromic element according to claim 1, wherein the electrochromic layer has a rotational torque of 500 mgf cm or more when measured using an automated gel time method A according to JIS K6910:2007.

3. 2. The electrochromic device according to claim 1, wherein the electrochromic layer comprises a plurality of electrochromic compounds.

4. 4. The electrochromic device according to claim 3, wherein the plurality of electrochromic compounds includes an anodic electrochromic compound and a cathodic electrochromic compound.

5. 2. The electrochromic device according to claim 1, wherein the polymer is poly(4-vinylpyridine) or poly(dimethylaminoethyl methacrylate).

6. 1. A method for manufacturing an electrochromic device having a first electrode, a second electrode, and an electrochromic layer including at least one electrochromic compound disposed between the first electrode and the second electrode, comprising: an electrochromic gel preparation step of preparing an electrochromic gel containing at least one electrochromic compound, a solvent, and a crosslinked polymer of a dimer or higher of a compound having a tertiary amine or cyclic imine in a side chain; a seal pattern forming step of forming a seal pattern on the first electrode to be filled with the electrochromic gel; a decompression step of decompressing the inside of the seal pattern after disposing the electrochromic gel in the region surrounded by the seal pattern on the first electrode; a bonding step of bonding the first electrode and the second electrode together under reduced pressure; A method for manufacturing an electrochromic element, comprising:

7. 7. The method for manufacturing an electrochromic element according to claim 6, wherein the electrochromic gel has a rotational torque of 500 mgf cm or more when measured using an automated gelation time method A according to JIS K6910:2007.

8. 7. The method for manufacturing an electrochromic element according to claim 6, wherein the electrochromic gel is gelled by heating an electrochromic gelling solution containing the electrochromic compound, the solvent, a polymer of dimer or higher of a compound having the tertiary amine or cyclic imine in a side chain, and a crosslinking agent.

9. 7. The method for manufacturing an electrochromic element according to claim 6, wherein the electrochromic compound is of a plurality of types.

10. 10. The method for manufacturing an electrochromic device according to claim 9, wherein the plurality of electrochromic compounds include an anodic electrochromic compound and a cathodic electrochromic compound.

11. 7. The electrochromic device according to claim 6, wherein the polymer is poly(4-vinylpyridine) or poly(dimethylaminoethyl methacrylate).

12. 6. An optical filter comprising: the electrochromic element according to claim 1; and a transistor connected to the electrochromic element.

13. A lens unit comprising: the optical filter according to claim 12; and an imaging optical system having a plurality of lenses.

14. 13. An imaging device comprising: the optical filter according to claim 12; and a light receiving element that receives light that has passed through the optical filter.

15. A window material comprising: the electrochromic element according to claim 1; and a transistor connected to the electrochromic element.

16. 6. An electrochromic mirror comprising: the electrochromic element according to claim 1; and a reflective member disposed inside or outside the electrochromic element.

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