JP7604173B2 - Organic compound, electrochromic element, optical filter, lens unit, imaging device, and window - Google Patents

Description

The present invention relates to an organic compound having electrochromic properties, an electrochromic element, an optical filter, a lens unit, an imaging device, and a window.

An electrochromic element is an element having a pair of electrodes and an electrochromic layer disposed between the pair of electrodes. It is an element that adjusts the amount of light passing through the electrochromic layer by applying a voltage to the pair of electrodes. In other words, an electrochromic element can control the light transmittance. Note that in this specification, electrochromic may be abbreviated to EC.

A variety of electrochromic materials are known, including inorganic materials, polymeric materials, and organic low-molecular-weight materials, whose optical absorption properties (coloration state and light transmittance) change due to an electrochemical redox reaction.

These materials have been used to apply EC elements to automobile light-switching mirrors, electronic paper, and other applications. These devices utilize the property that a wide variety of color tones can be displayed by selecting the material, and many electrochromic compounds have been developed to date.

Patent Document 1 describes an organic compound of the following structural formula that becomes colored in a reduced state.

JP 2019-137672 A

To put electrochromic elements into practical use, compounds with various characteristics depending on the type of device and application are needed, and electrochromic compounds with properties different from those of the compounds described in Patent Document 1 are needed.

The present invention has been made in consideration of the above problems, and aims to provide an organic compound that absorbs light in the region around 500 nm through an oxidation-reduction reaction, thereby coloring and decolorizing the compound.

The present invention provides an organic compound represented by the following general formula (1):

一般式（１）おいて、Ｘ_１及びＸ_２は、置換あるいは無置換のアルキル基、置換あるいは無置換のアルコキシ基、置換あるいは無置換のアリール基、置換あるいは無置換の複素環基および置換あるいは無置換のアラルキル基からそれぞれ独立に選ばれる。

In general formula (1), _X1 and _X2 are each independently selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, and a substituted or unsubstituted aralkyl group.

_R1 to _R8 are each independently selected from a hydrogen atom and a substituent. The substituent represented by _R1 to _R8 is any one of a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.

R ₉ and R ₁₀ are either a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

The present invention provides an organic compound that absorbs light in the region around 500 nm through an oxidation-reduction reaction, and becomes colored or decolorized.

FIG. 1 is a schematic cross-sectional view of an example of an electrochromic element according to an embodiment. FIG. 2 is a schematic diagram illustrating an example of a driving device including an electrochromic element according to an embodiment. 1A is a schematic diagram of an example of an imaging device in which an optical filter is disposed in a lens unit, and FIG. 1B is a schematic diagram of an example of an imaging device in which an optical filter is disposed in the imaging device. 4A is a schematic view showing a window using an EC element according to the present embodiment, and FIG. 4B is a schematic cross-sectional view taken along the line X-X' of FIG. FIG. 1 is a diagram showing ultraviolet-visible absorption spectra of exemplary compound A-31 in a colored state and a decolorized state. FIG. 1 shows ultraviolet-visible absorption spectra of exemplary compound A-22 in a colored state and a decolorized state. FIG. 1 is a diagram showing ultraviolet-visible absorption spectra of exemplary compound A-25 in a colored state and a decolorized state.

The organic compound according to this embodiment is characterized by being represented by the following general formula (1). Since the organic compound has electrochromic properties, it can be called an electrochromic compound.

一般式（１）おいて、Ｘ_１及びＸ_２は、置換あるいは無置換のアルキル基、置換あるいは無置換のアルコキシ基、置換あるいは無置換のアリール基、置換あるいは無置換の複素環基および置換あるいは無置換のアラルキル基からそれぞれ独立に選ばれる。Ｘ_１及びＸ_２は、上述の中でも、アルキル基、アリール基、アラルキル基であってよい。

In the general formula (1), _X1 and _X2 are each independently selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, and a substituted or unsubstituted aralkyl group. Among the above, _X1 and _X2 may be an alkyl group, an aryl group, or an aralkyl group.

R ₁ to R ₈ are each independently selected from a hydrogen atom and a substituent. The substituents represented by R ₁ to R ₈ are any of a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. R ₁ to R ₈ may be a hydrogen atom among the above.

_R9 and _R10 are each independently selected from substituents. The substituents represented by _R9 and _R10 are either an alkyl group which may have a substituent or an aryl group which may have a substituent. More preferably, _R9 and _R10 are the same substituent.

The alkyl group in this embodiment may have 1 to 20 carbon atoms. The alkyl group preferably has 1 to 8 carbon atoms, and may be linear, branched, or cyclic. A hydrogen atom in the alkyl group may be replaced with a halogen atom, preferably a fluorine atom. A carbon atom in the alkyl group may be replaced with an ester group or a cyano group. Specific examples of the alkyl group include a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, a tertiary butyl group, an octyl group, a cyclohexyl group, and a trifluoromethyl group.

Examples of the aralkyl group according to this embodiment include a benzyl group and a phenethyl group. The aralkyl group may have a substituent, specifically, an alkyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms. The hydrogen atom of the alkyl group or alkoxy group may be replaced with a halogen atom, preferably a fluorine atom.

The alkoxy group according to this embodiment may have 1 to 20 carbon atoms. The alkoxy group preferably has 1 to 8 carbon atoms and may be linear, branched, or cyclic. Specific examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropyloxy group, a tertiary butyloxy group, an octyloxy group, a cyclohexyloxy group, and a trifluoromethyloxy group. The hydrogen atom of the alkoxy group may be replaced by a halogen atom. When the hydrogen atom is replaced by a halogen atom, a fluorine atom is preferable.

Examples of the aryl group according to the present embodiment include a phenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a naphthyl group, a fluoranthenyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a tetracenyl group, a pentacenyl group, a triphenylenyl group, and a perylenyl group. When the aryl group has a substituent, it may have at least one of a halogen atom, an alkyl group having 1 to 8 carbon atoms, and an alkoxy group having 1 to 8 carbon atoms. The hydrogen atom of the alkyl group or alkoxy group may be replaced with a halogen atom, preferably a fluorine atom.

Examples of the heterocyclic group according to this embodiment include a thienyl group, a pyrrolyl group, a pyridyl group, an oxazolyl group, an oxadiazolyl group, a thiazolyl group, a thiadiazolyl group, a terthienyl group, a quinolyl group, an isoquinolyl group, and a carbazolyl group. When the heterocyclic group has a substituent, it may have at least one of an alkyl group having 1 to 8 carbon atoms and an alkoxy group having 1 to 8 carbon atoms. The hydrogen atom of the alkyl group or the alkoxy group may be replaced with a halogen atom, preferably a fluorine atom.

Halogen atoms in this embodiment include fluorine, chlorine, bromine, iodine, etc.

When _X1 and _X2 are alkyl groups, they may have an adsorption group or an acid ester group thereof for adsorption to a porous electrode. Specific examples of the adsorption group or the acid ester group thereof include a carboxyl group and a carboxyl ester group, a sulfonic acid group and a sulfonic acid ester group, a phosphonic acid group and a phosphonic acid ester group, a trialkoxysilyl group, etc. Furthermore, in order to improve solubility in an organic solvent, the terminal of the alkyl group may have an ionic group such as pyridinium or quinolinium.

When the aralkyl group and aryl group represented by _X1 and _X2 have an alkyl group or an alkoxy group as a substituent, the terminal may have an adsorptive group or an acid ester group thereof that adsorbs to a porous electrode, or an ionic group to improve solubility in an organic solvent. Specific examples of the adsorptive group or the acid ester group thereof and the ionic group are the same as those given for the alkyl group represented by _X1 and _X2 .

The organic compound represented by general formula (1) may exist with an anion. When it exists with an anion, it is described as follows:

Ａ_１ ^－およびＡ_２ ^－は、それぞれ独立に一価のアニオンを表す。

A ₁ ^- and A ₂ ^- each independently represent a monovalent anion.

The anions A ₁ ^- and A ₂ ^- may be the same or different and are selected from anions such as PF ₆ ^- , ClO ₄ ^- , BF ₄ ^- , AsF ₆ ^- , SbF ₆ ^- , CF ₃ SO ₃ ^- , (CF ₃ SO ₂ ) ₂ N ^- and halogen anions such as Br ^- , Cl ^- , I ^- . Preferably, they are any of PF ₆ ^- , ClO ₄ ^- , BF ₄ ^- , CF ₃ SO ₃ ^- , and (CF ₃ SO ₂ ) ₂ N ^- . More preferably, A ₁ ^- and A ₂ ^- are the same anion.

The method for producing the organic compound according to the present embodiment is not particularly limited, but for example, the organic compound can be produced by the method shown below. When _X1 and _X2 are an alkyl group and an aralkyl group, the organic compound can be obtained by reacting an organic compound represented by the following general formula (2) with a halide in a predetermined solvent, and then performing an anion exchange reaction with a salt containing a desired anion in the predetermined solvent.

On the other hand, when X ₁ and X ₂ are aryl groups, the compound can be obtained by reacting with 2,4-dinitrophenyl halide, reacting the resulting compound with a desired arylamine, and then carrying out an anion exchange reaction with a salt containing an anion in a predetermined solvent. Alternatively, the compound can be obtained by reacting with a hypervalent iodine compound, followed by an anion exchange reaction. Furthermore, by selecting the solvent and reaction temperature, it is also possible to react only one of the imines. By repeating the reaction, it is also possible to introduce different substituents into the two imines.

上記一般式（２）で表される有機化合物の製造方法は特に制限はないが、例えば、以下に示す製造方法に従い製造することができる。合成ルート内のＲ_１乃至Ｒ_１０は一般式（１）と同様に水素原子または置換基を表し、Ｘはハロゲン原子を表しＲはアルキル基を表す。

The method for producing the organic compound represented by the above general formula (2) is not particularly limited, but it can be produced, for example, according to the production method shown below. In the synthesis route, _R1 to _R10 represent a hydrogen atom or a substituent as in the general formula (1), X represents a halogen atom, and R represents an alkyl group.

中間体１は、３－カルボン酸エステル－４－ハロゲノ－ピリジン誘導体と５－ハロゲノ－キノリン誘導体とのカップリングにより合成することができる。中間体１に塩基存在下、所望のハロゲン体と反応すること中間体２を合成することができる。一般式（２）で表される有機化合物は、中間体２を酸触媒存在下、分子内フリーデル・クラフツ反応を行うことで合成することができる。

Intermediate 1 can be synthesized by coupling a 3-carboxylate-4-halogeno-pyridine derivative with a 5-halogeno-quinoline derivative. Intermediate 2 can be synthesized by reacting intermediate 1 with a desired halogen in the presence of a base. An organic compound represented by general formula (2) can be synthesized by subjecting intermediate 2 to an intramolecular Friedel-Crafts reaction in the presence of an acid catalyst.

Specific structural formulas of organic compounds according to the present invention are shown below. However, the compounds according to the present invention are not limited to these.

例示化合物Ａ１乃至Ａ９は、一般式（１）におけるＸ_１及びＸ_２がアルキル基であり、Ｒ_９及びＲ_１０がアルキル基である、例示化合物である。

Exemplary compounds A1 to A9 are compounds in which _X1 and _X2 in general formula (1) are alkyl groups, and _R9 and _R10 are alkyl groups.

In the exemplary compounds A10 to A12, _X1 and _X2 in the general formula (1) are alkyl groups, and at least one of _R9 and _R10 is an aryl group. The aryl group is particularly a phenyl group.

In the exemplary compounds A13 to A23, at least one of _X1 and _X2 in the general formula (1) is an aryl group, particularly a phenyl group. A23 has an alkyl group in _R2 . That is, it is an example having a substituent in any of _R1 to _R8 .

Exemplary compounds A24 to A29 are exemplary compounds having a substituent at any one of _R1 to _R8 . That is, they are examples having a substituent at _R2 or _R7 .

Exemplary compounds A30 and A31 are compounds having a fluoromethyl group in _X1 and _X2 , that is, they are examples having an alkyl group substituted with a halogen atom in X1 and X2.

In the exemplary compounds A32 to A36, _X1 and _X2 each have a substituent having a hetero atom.

The organic compound according to this embodiment has a structure represented by general formula (1), and therefore is a compound that has high transparency when dissolved in a solvent. In addition, the organic compound according to this embodiment is a compound that becomes colored in a reduced state. A compound that becomes colored in a reduced state is a compound whose visible light transmittance in a reduced state is lower than its visible light transmittance in an oxidized state.

The organic compound according to this embodiment is an electrochromic material that exhibits stable coloring at ambient temperatures, and can be used in EC elements, optical filters that use the same, lens units, imaging devices, and the like.

<EC element>
The EC compound according to the present embodiment can be used as an electrochromic layer of an electrochromic element. The electrochromic element according to the present embodiment will be described below with reference to the drawings.

The EC element 1 in FIG. 1 has a pair of transparent substrates 10, a pair of electrodes 11, and an EC layer 12 disposed between the pair of electrodes. The distance between the pair of electrodes is kept constant by a spacer 13.

The EC layer contains the organic compound according to the present invention. This EC layer may have a layer made of an EC compound and a layer made of an electrolyte. The EC layer may also be provided as a solution containing an EC compound and an electrolyte. In this form, the EC layer can be said to be a solution layer. In the EC element according to this embodiment, the EC layer is preferably a solution layer. When the EC layer is a solution layer, the EC organic compound, the solution, and other dissolved substances may be collectively referred to as an EC medium.

Next, we will explain the components that make up the EC element according to this embodiment.

The electrolyte is not limited as long as it is an ion-dissociating salt and has good solubility in a solvent and high compatibility with a solid electrolyte. Among them, 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. Specifically, LiClO ₄ , LiSCN, LiBF ₄ , LiAsF ₆ , LiCF ₃ SO ₃ , LiPF ₆ , LiI, NaI, NaSCN, NaClO ₄ , NaBF ₄ , NaAsF _{6 , KSCN ,} KCl _{and other alkali metal salts of Li , Na , K , etc .; 4} NBr, (C ₂ H ₅ ) ₄ NClO ₄ , (n-C ₄ H ₉ ) ₄ NClO ammonium salts such as quaternary ammonium salts of _{ammonium phosphate,} etc. and cyclic quaternary ammonium salts.

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 it is preferable to use a solvent that has polarity. 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, benzonitrile, dimethylacetamide, methylpyrrolidinone, and dioxolane.

Furthermore, the EC medium may contain a polymer or a gelling agent to make it highly viscous or gel-like. These polymers and gelling agents may also be called thickeners. By containing a thickener and increasing the viscosity of the EC solution, the organic compounds are less likely to form associations, and the temperature dependence of the absorption spectrum can be reduced. Therefore, it is preferable that the EC solution contains a thickener.

The viscosity of the EC solution may be 10 cP or more and 5000 cP or less, or 50 cP or more and 1000 cP or less. The viscosity of the EC solution may be 150 cP or less, preferably 100 cP or less, and more preferably 65 cP or less. The viscosity of the EC solution may be 20 cP or more, and preferably 50 cP or more.

The thickener may be present in a weight ratio of 20 wt% or less, assuming the total weight of the EC solution to be 100 wt%. Preferably, the weight ratio is 1 wt% or more and 15 wt% or less, and more preferably, 5 wt% or more and 10 wt% or less.

The above polymer is not particularly limited, and examples thereof include polyacrylonitrile, carboxymethyl cellulose, polyvinyl chloride, polyalkylene oxide, polyurethane, polyacrylate, polymethacrylate, polyamide, polyacrylamide, polyester, Nafion (registered trademark), etc. Polymethyl methacrylate, polyethylene oxide, and polypropylene oxide are preferred.

When the viscosity of the EC solution is high, the movement of molecules in the EC solution can be suppressed, which may help to suppress association. On the other hand, it is not desirable for the viscosity to be too high, as it will suppress the movement of electrons in the EC solution, slowing down the response speed of the EC element.

Next, the transparent substrate and the transparent electrode will be described. As the transparent substrate, for example, colorless or colored glass, reinforced glass, etc., or colorless or colored transparent resin is used. In this embodiment, "transparent" means that the transmittance of visible light is 90% or more. Specific examples include polyethylene terephthalate, polyethylene naphthalate, polynorbornene, polyamide, polysulfone, polyethersulfone, polyetheretherketone, polyphenylene sulfide, polycarbonate, polyimide, polymethyl methacrylate, etc.

Examples of materials for the transparent electrode include metals and metal oxides such as indium tin oxide (ITO), fluorine-doped tin oxide (FTO), tin oxide (NESA), indium zinc oxide (IZO), silver oxide, vanadium oxide, molybdenum oxide, gold, silver, platinum, copper, indium, and chromium, silicon-based materials such as polycrystalline silicon and amorphous silicon, and carbon materials such as carbon black, graphite, and glassy carbon. In addition, conductive polymers whose conductivity has been improved by doping treatment, such as polyaniline, polypyrrole, polythiophene, polyacetylene, polyparaphenylene, and complexes of polyethylenedioxythiophene (PEDOT) and polystyrenesulfonic acid, are also suitable for use.

Furthermore, a porous electrode may be provided on the electrode. The porous electrode is preferably a material with a large surface area, such as a porous shape with fine pores on the surface and inside, a rod shape, or a wire shape. Examples of materials that can be used for the porous electrode include metals, metal oxides, and carbon. More preferably, the material is a metal oxide such as titanium oxide, tin oxide, iron oxide, strontium oxide, tungsten oxide, zinc oxide, tantalum oxide, vanadium oxide, indium oxide, nickel oxide, manganese oxide, or cobalt oxide.

The spacer is disposed between a pair of transparent electrodes and provides a space for accommodating the EC layer having the EC compound of the present invention. Specifically, polyimide, polytetrafluoroethylene, fluororubber, epoxy resin, etc. can be used. This spacer makes it possible to maintain the distance between the electrodes of the EC element.

The EC element according to this embodiment may have a liquid inlet formed by a pair of electrodes and a spacer. After a composition containing an EC compound is injected through the liquid inlet, the inlet can be covered with a sealing member and further sealed with an adhesive or the like to form an element. The sealing member also plays a role in isolating the adhesive and the EC compound so that they do not come into contact with each other. The shape of the sealing member is not particularly limited, but a tapered shape such as a wedge shape is preferable.

The method for forming the EC element according to this embodiment is not particularly limited, and a method can be used in which a liquid containing an EC compound that has been prepared in advance is injected into the gap between a pair of electrode substrates by a vacuum injection method, an air injection method, a meniscus method, or the like.

The EC element according to the present embodiment may have the organic compound according to the present embodiment and a different organic compound (second organic compound) from this organic compound. The second organic compound may be one type or multiple types, and may be a compound that is colored in an oxidized state, a compound that is colored in a reduced state, or a compound that has both properties. Since the organic compound represented by the general formula (1) is a compound that is colored in a reduced state, it is preferable that the second organic compound is a compound that is colored in an oxidized state. A compound that is colored in an oxidized state is a compound whose visible light transmittance in an oxidized state is lower than the visible light transmittance in a reduced state. It is sufficient that the transmittance changes in any part of the visible light range, and the transmittance does not have to change in the entire visible light range. Specifically, the organic compound according to the present embodiment can absorb a desired color as an EC element by combining it with a coloring material of another color. The different organic compound during coloring preferably has an absorption wavelength in the range of 400 nm to 800 nm, more preferably has an absorption wavelength in the range of 420 nm to 700 nm. Having an absorption wavelength in a specific range means that the peak of the absorption spectrum is in a specific range. By combining the organic compound of the present invention with multiple other materials, it is possible to create an EC element that absorbs the entire visible range and is colored black.

The EC element according to this embodiment preferably contains five or more types of EC compounds in addition to the organic compound according to the present invention. This is because a filter containing an EC element is more likely to uniformly absorb light of each wavelength.

Other EC compounds according to this embodiment include, for example, compounds having the following structural formula:

Other EC compounds that become colored in the oxidized state include oligothiophene-based compounds, phenazine-based compounds such as 5,10-dihydro-5,10-dimethylphenazine and 5,10-dihydro-5,10-diisopropylphenazine, metallocene-based compounds such as ferrocene, tetra-t-butylferrocene and titanocene, phenylenediamine-based compounds such as N,N',N,N'-tetramethyl-p-phenylenediamine, and pyrarizone-based compounds such as 1-phenyl-2-pyrazoline.

Compounds that become colored in a reduced state include N,N'-diheptylbipyridinium diperchlorate, N,N'-diheptylbipyridinium ditetrafluoroborate, N,N'-diheptylbipyridinium dihexafluorophosphate, N,N'-diethylbipyridinium diperchlorate, N,N'-diethylbipyridinium ditetrafluoroborate, N,N'-diethylbipyridinium dihexafluorophosphate, N,N'-dibenzylbipyridinium diperchlorate, N,N'-dibenzylbipyridinium ditetrafluoroborate, N,N'-dibenzyl ...borate, N,N'-dibenzylbipyridinium diperchlorate, N,N'-dibenzylbipyridinium dihexafluoroborate, N,N'-dibenzylbipyridinium dihexafluoroborate, N,N'-dibenzylbipyridinium diperchlorate, N,N'-dibenzylbipyridinium dihexafluoroborate, N,N'-dibenzylbipyridinium diperchlorate, N,N'-dibenzylbipyridinium dihexafluoroborate, N,N'-dibenzylbi Examples of such compounds include viologen compounds such as N,N'-diphenylbipyridinium dihexafluorophosphate, N,N'-diphenylbipyridinium diperchlorate, N,N'-diphenylbipyridinium ditetrafluoroborate, and N,N'-diphenylbipyridinium dihexafluorophosphate; anthraquinone compounds such as 2-ethylanthraquinone, 2-t-butylanthraquinone, and octamethylanthraquinone; ferrocenium salt compounds such as ferrocenium tetrafluoroborate and ferrocenium hexafluorophosphate; and styrylated compounds.

In this embodiment, the phenazine compound is a compound containing a 5,10-dihydrophenazine skeleton in its chemical structure. The phenazine compound includes a compound having a substituent in 5,10-dihydrophenazine. For example, the hydrogen atoms at the 5th and 10th positions of 5,10-dihydrophenazine may be substituted with an alkyl group such as a methyl group, an ethyl group, or a propyl group, or an aryl group such as a phenyl group. The phenazine compound may be a compound having an alkyl group with 1 to 20 carbon atoms in 5,10-dihydrophenazine. The phenazine compound may be a compound having an alkoxy group with 1 to 20 carbon atoms in 5,10-dihydrophenazine. The phenazine compound may be a compound having an aryl group with 4 to 60 carbon atoms in 5,10-dihydrophenazine. The same applies to other compounds, such as viologen compounds.

Of the above, the second organic compound is preferably a phenazine-based compound, a metallocene-based compound, a phenylenediamine-based compound, or a pyrazoline-based compound.

The compounds contained in the EC layer of the EC element according to this embodiment can be extracted and analyzed by known methods to confirm that they are present in the EC element. For example, they can be extracted by chromatography and analyzed by NMR. Furthermore, if the electrochromic layer is a solid, it can be analyzed by TOF-SIMS or the like.

<Applications of EC elements>
The EC element according to this embodiment can be used in optical filters, lens units, imaging devices, window materials, and the like.

<Optical filter>
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 an active region.

The optical filter has an EC element according to this embodiment and a driving device connected to the EC element. FIG. 2 is a schematic diagram showing an example of a driving device 20 for an EC element and an EC element driven by the driving device 20. The driving device 20 for the EC element 1 of this embodiment has a driving power supply 8, a resistance switch 9, and a controller 7.

The driving power supply 8 applies to the EC element a voltage necessary for the EC material contained in the EC layer to cause an electrochemical reaction. It is more preferable that the driving voltage is a constant voltage. 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 potential difference and molar absorption coefficient of the materials, so a constant voltage is preferable. The driving power supply 8 starts applying voltage or maintains the applied state by a signal from the controller 7, and the constant voltage application state is maintained during the period in which the light transmittance of the EC element is controlled.

The method of controlling the transmittance of the EC element by the controller 7 is adapted to the element being used. Specifically, there is a method of inputting predefined conditions to the EC element 1 for the desired set value of transmittance, or a method of comparing the set value of transmittance with the transmittance of the EC element 1 and selecting and inputting conditions that match the set value. Examples of parameters that can be changed include voltage, current, and duty ratio. The controller 7 can change the color density of the EC element by changing the voltage, current, or duty ratio.

In this embodiment, known means can be used to change the voltage, change the current, and modulate the pulse width. Pulse width modulation can also be performed as follows.

The resistance switch 9 switches between resistor R1 (not shown) and resistor R2, which is larger than resistor R1, and connects them in series in a closed circuit including the drive power source 8 and the EC element. The resistance value of resistor R1 is preferably smaller than the largest impedance of the element closed circuit, and is preferably 10 Ω or less. The resistance value of resistor R2 is preferably larger than the largest impedance of the element closed circuit, and is preferably 1 MΩ or more. Resistor R2 may be air. In this case, strictly speaking the closed circuit becomes an open circuit, but it can be considered as a closed circuit by regarding the air as resistor R2.

The controller 7 sends a switching signal to the resistor switch 9 to control the switching of resistors R1 and R2.

The controller 7 may generate a PWM signal using a comparator or the like without using a resistor switch.

<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 1. The optical filter may be provided either between the plurality of lenses or outside the lens. The optical filter is preferably provided on the optical axis of the lens.

<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 be in a form in which a main body having a light receiving element and a lens unit having a lens can be separated. In this case, when the imaging device can be separated into a main body and a lens unit, the present invention also includes a form in which an optical filter separate from the imaging device is used during imaging. In this case, the optical filter may be disposed outside the lens unit, between the lens unit and the light receiving element, between multiple lenses (when the lens unit has multiple lenses), and the like.

Figure 3(a) is a schematic diagram of an example of an imaging device in which an optical filter is disposed in a lens unit, and Figure 3(b) is a schematic diagram of an example of an imaging device in which an optical filter is disposed in the imaging device.

The imaging device 100 is an imaging device having a lens unit 102 and an imaging unit 103. The lens unit 102 has an optical filter 101 and an imaging optical system having a plurality of lenses or a lens group. The optical filter 101 is the optical filter of the present embodiment described above.

Lens unit 102, for example, in FIG. 3(a) represents a rear-focus type zoom lens that performs focusing behind the aperture. It has four lens groups, in order from the object side, a first lens group 104 with positive refractive power, a second lens group 105 with negative refractive power, a third lens group 106 with positive refractive power, and a fourth lens group 107 with positive refractive power. Magnification is changed by changing the distance between second lens group 105 and third lens group 106, and focusing is performed by moving some of the lens groups in fourth lens group 107.

The lens unit 102, for example, has an aperture stop 108 between the second lens group 105 and the third lens group 106, and also has an optical filter 101 between the third lens group 106 and the fourth lens group 107. The lens unit is arranged so that light passing through each of the lens groups 104 to 107, the aperture stop 108, and the optical filter 101 passes through, and the amount of light can be adjusted using the aperture stop 108 and the optical filter 101.

The lens unit 102 is detachably connected to the imaging unit 103 via a mounting member (not shown).

In this embodiment, the optical filter 101 is disposed between the third lens group 106 and the fourth lens group 107 in the lens unit 102, but the imaging device 100 is not limited to this configuration. For example, the optical filter 101 may be disposed either in front of (on the subject side) or behind (on the imaging unit 103 side) the aperture stop 108, or in front of, behind, or between any of the first to fourth lens groups 104 to 107. Placing the optical filter 101 at a position where light converges has the advantage of making the area of the optical filter 101 smaller.

The configuration of the lens unit 102 is not limited to the above configuration, and can be selected as appropriate. For example, in addition to the rear focus type, it can be an inner focus type in which focusing is performed in front of the aperture, or other types. In addition to zoom lenses, special lenses such as fisheye lenses and macro lenses can also be selected as appropriate.

The imaging unit 103 has a glass block 109 and a light receiving element 110. The glass block 109 is a glass block such as a low-pass filter, a face plate, or a color filter. The light receiving element 110 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. It may also be an optical sensor such as a photodiode, and any device that acquires and outputs information on the intensity or wavelength of light can be used as appropriate.

When the optical filter 101 is incorporated in the lens unit 102 as shown in FIG. 3(a), the driving device may be disposed inside the lens unit 102 or outside the lens unit 102. When disposed outside the lens unit 102, the EC element 1 in the lens unit 102 is connected to the driving device through wiring to control the driving.

In addition, in the configuration of the imaging device 100 described above, the optical filter 101 is disposed inside the lens unit 102. However, the present invention is not limited to this configuration, and it is sufficient that the optical filter 101 is disposed at an appropriate location inside the imaging device 100, and the light receiving element 110 is disposed so as to receive light that has passed through the optical filter 101.

For example, as shown in FIG. 3B, the imaging unit 103 may have an optical filter 101. FIG. 3B 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 an optical filter in the imaging unit 103. In FIG. 3B, for example, the optical filter 101 is disposed immediately before the light receiving element 110. When the imaging device itself has the optical filter 101 built in, the connected lens unit 102 itself does not need to have the optical filter 101, so it is possible to configure a dimmable imaging device using an existing lens unit 102.

The imaging device 100 of this embodiment can be applied to products that have a combination of light amount adjustment and a light receiving element. For example, it can be used in cameras, digital cameras, video cameras, and digital video cameras, and can also be applied to products that have built-in imaging devices, such as mobile phones, smartphones, PCs, and tablets.

According to the imaging device 100 of this embodiment, by using the optical filter 101 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.

<Windows>
The window according to the present 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. The active element may be, for example, a transistor. The transistor may have an oxide semiconductor such as InGaZnO in an active region. The window according to the present embodiment may also be called a variable transmittance window.

Figure 4(a) is an overview diagram showing a light control window as a window material using the EC element according to this embodiment, and Figure 4(b) is a schematic diagram showing the X-X' cross section of Figure 4(a). The light control window 111 of this embodiment is composed of an EC element 1 (optical filter), a transparent plate 113 that holds it, and a frame 112 that surrounds and integrates the whole. The EC element 1 has a drive unit (not shown), which may be integrated within the frame 112, or may be arranged outside the frame 112 and connected to the EC element 1 through wiring.

The transparent plate 113 is not particularly limited as long as it is made of a material with high light transmittance, and is preferably made of a glass material considering its use as a window. The material of the frame 112 is not important, but anything that covers at least a portion of the EC element 1 and has an integrated form may be considered as a frame. In FIG. 4, the EC element 1 is a component independent of the transparent plate 113, but for example, the transparent substrate 10 of the EC element 1 may be considered as the transparent plate 113.

Such a light-control window can be used, for example, to adjust the amount of sunlight entering a room during the day. It can also be used to adjust the amount of heat in addition to the amount of sunlight, so it can be used to control the brightness and temperature inside a room. It can also be used as a shutter to block the view from outside into the room. In addition to glass windows for buildings, such light-control windows can also be used for windows in vehicles such as cars, trains, airplanes, and ships.

In this way, the EC element 1 containing the organic compound represented by general formula (1) in the EC layer 12 can be used for optical filters, lens units, imaging devices, window materials, etc. Each of the optical filters, lens units, imaging devices, and window materials of this embodiment can provide various absorption colors by using the organic compound represented by general formula (1) alone or in combination with an EC compound having colored absorption in other wavelength bands. Furthermore, since each of the optical filters, lens units, imaging devices, and window materials of this embodiment contains the organic compound represented by general formula (1), the transparency in the decolorized state can be improved.

Also, by providing a reflective member on one of the light paths of the electrochromic element, it can be made into an electrochromic mirror. The electrochromic mirror may be provided in an automobile as an anti-glare mirror. The electrochromic mirror can be constructed by having an electrochromic element and a reflective member inside or outside the electrochromic element. Having a reflective member inside means that the electrode of the electrochromic element is reflective. Having a reflective member outside means that a reflective member is provided in contact with the transparent electrode of the electrochromic element or via another transparent member.

The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these.

[Example 1: Synthesis of Example Compound A-22]

(1) Synthesis of intermediate 11 A reaction vessel was charged with 692 mg (4.0 mmol) of quinoline-4-boronic acid, 755 mg (4.4 mmol) of methyl 4-chloropyridine-3-carboxylate, 24 ml of 1,4-dioxane, and 0.6 ml of water, and dissolved oxygen was removed with nitrogen. Next, 54 mg (0.24 mmol) of palladium acetate, 197 mg (0.48 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (S-Phos), and 1.66 g (12 mmol) of potassium carbonate were added under a nitrogen atmosphere, and the reaction was carried out at 100°C for 8 hours. After adding water to the reaction solution to stop the reaction, the aqueous layer was extracted with ethyl acetate, and the mixture was separated and purified by silica gel chromatography (mobile phase: hexane/ethyl acetate) to obtain intermediate 11 (759 mg, yield 77%).

(2) Synthesis of intermediate 12 In a reaction vessel, 529 mg (2.0 mmol) of intermediate 11 and anhydrous tetrahydrofuran (20 ml) were charged and cooled to -5°C. Next, 5.3 ml of methylmagnesium bromide solution (approximately 3.0 M tetrahydrofuran solution, 16.0 mmol) was slowly added dropwise and stirred for 1 hour, and then the temperature was raised to room temperature. An aqueous ammonium chloride solution was added to this solution to stop the reaction, and the solution was extracted with ethyl acetate and separated and purified by silica gel chromatography (mobile phase: chloroform/methanol) to obtain intermediate 12 (486 mg, yield 92%).

(3) Synthesis of Intermediate 13 In a reaction vessel, 486 mg (1.8 mmol) of Intermediate 12 and trifluoromethanesulfonic acid (5 mL) were charged and stirred for 8 hours at 80° C. After neutralizing this solution with an aqueous sodium hydroxide solution, the aqueous layer was extracted with ethyl acetate and separated and purified by silica gel chromatography (mobile phase: hexane/ethyl acetate) to obtain Intermediate 13 (412 mg, yield 91%).

(4) Synthesis of Exemplary Compound A-22 138 mg (0.56 mmol) of intermediate 13, 1.51 g (2.80 mmol) of bis(4-tert-butylphenyl)iodonium hexafluorophosphate, 18 mg (0.10 mmol) of copper(II) acetate monohydrate, and 2.5 mL of N,N-dimethylformamide were added to a reaction vessel, and the mixture was reacted at 100° C. for 20 hours. After the reaction was completed, the mixture was concentrated under reduced pressure, and an acetonitrile solution (10 ml) of tetrabutylammonium bromide (2 g) was added. The precipitated solid was collected by filtration and dissolved in water. An aqueous solution of 200 mg of ammonium hexafluorophosphate was added dropwise to the mixture, and the mixture was stirred at room temperature for 3 hours. The precipitated crystals were filtered and washed with water, isopropyl alcohol, and diethyl ether in that order, and 250 mg (yield: 56%) of exemplary compound 22 was obtained. The structure of this compound was confirmed by NMR measurement.
^1H NMR (DMSO- _d6 , 500MHz) σ (ppm): 9.98 (s, 1H), 9.94 (d, 1H), 9.58 (d, 1H), 9.54 (d, 1H), 9.41 (d, 1H), 8.53 (d, 1H), 8. 33 (t, 1H), 7.95 (m, 2H), 7.84 (m, 6H), 7.66 (d, 1H), 1.99 (s, 6H)), 1.42 (s, 9H), 1.39 (s, 9H)

[Example 2 <Synthesis of Exemplary Compound A-30>]
A reaction vessel was charged with 99 mg (0.4 mmol) of intermediate 13, 202 mg (0.9 mmol) of 1,1,1-trifluoro-3-iodopropane, and 5 ml of acetonitrile, and the mixture was stirred at 80° C. for 48 hours. After the reaction was completed, ethyl acetate was added, and the precipitated crystals were filtered and washed with ethyl acetate to obtain 240 mg (yield: 80%) of exemplary compound A-30. The structure of this compound was confirmed by NMR measurement.
^1H NMR (DMSO- _d6 , 500MHz) σ (ppm): 9.81 (m, 2H), 9.30 (m, 2H), 9.17 (d, 1H), 8.69 (d, 1H), 8.48 (m, 2H), 5.19 (t, 2H), 4.80 (t, 2H), 2.58 (m, 2H), 2.30 (m, 2H), 1.91 (s, 6H)

[Example 3 <Synthesis of Exemplary Compound A-31>]
75 mg (0.1 mmol) of exemplary compound A-30 was dissolved in water and a small amount of acetone, and an aqueous solution containing 300 mg of potassium hexafluorophosphate was added dropwise thereto, followed by stirring at room temperature for 3 hours. The precipitated crystals were filtered and recrystallized from acetonitrile/isopropyl alcohol to obtain 71 mg (yield: 90%) of exemplary compound A-31. The structure of this compound was confirmed by NMR measurement.
^1H NMR (DMSO- _d6 , 500MHz) σ (ppm): 9.81 (m, 2H), 9.30 (m, 2H), 9.17 (d, 1H), 8.69 (d, 1H), 8.48 (m, 2H), 5.19 (t, 2H), 4.80 (t, 2H), 2.58 (m, 2H), 2.30 (m, 2H), 1.91 (s, 6H)

[Example 4 <Synthesis of Example Compound A-24>]

(1) Synthesis of intermediate 21 A reaction vessel was charged with 692 mg (4.0 mmol) of quinoline-4-boronic acid, 817 mg (4.4 mmol) of methyl 4-chloro-6-methylpyridine-3-carboxylate, 24 ml (1,4-dioxane), and 0.6 ml of water, and dissolved oxygen was removed with nitrogen. Next, 54 mg (0.24 mmol) of palladium acetate, 197 mg (0.48 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (S-Phos), and 1.66 g (12 mmol) of potassium carbonate were added under a nitrogen atmosphere, and the reaction was carried out at 100°C for 8 hours. After adding water to the reaction solution to stop the reaction, the aqueous layer was extracted with ethyl acetate, and the mixture was separated and purified by silica gel chromatography (mobile phase: hexane/ethyl acetate) to obtain intermediate 21 (781 mg, yield 75%).

(2) Synthesis of intermediate 22 In a reaction vessel, 56 mg (2.0 mmol) of intermediate 21 and anhydrous tetrahydrofuran (20 ml) were charged and cooled to -5°C. Next, 5.3 ml of methylmagnesium bromide solution (approximately 3.0 M tetrahydrofuran solution, 16.0 mmol) was slowly added dropwise and stirred for 1 hour, and then the temperature was raised to room temperature. An aqueous ammonium chloride solution was added to this solution to stop the reaction, and the solution was extracted with ethyl acetate and separated and purified by silica gel chromatography (mobile phase: chloroform/methanol) to obtain intermediate 22 (490 mg, yield 88%).

(3) Synthesis of Intermediate 23 In a reaction vessel, 490 mg (1.8 mmol) of Intermediate 12 and trifluoromethanesulfonic acid (5 mL) were charged and stirred for 8 hours at 80° C. After neutralizing this solution with an aqueous sodium hydroxide solution, the aqueous layer was extracted with ethyl acetate and separated and purified by silica gel chromatography (mobile phase: hexane/ethyl acetate) to obtain Intermediate 23 (421 mg, yield 92%).

(4) Synthesis of Exemplary Compound A-24 104 mg (0.4 mmol) of Intermediate 23, 166 mg (0.9 mmol) of 1-iodobutane, and 5 ml of DMF were placed in a reaction vessel, and stirred at 80° C. for 16 hours. After the reaction was completed, ethyl acetate was added, and the precipitated crystals were filtered and washed with ethyl acetate to obtain 214 mg (yield: 80%) of Exemplary Compound A-24. The structure of this compound was confirmed by NMR measurement.
^1H NMR (DMSO- _d6 , 500MHz) σ (ppm): 9.83 (d, 1H), 9.66 (s, 1H), 9.23 (s, 1H), 9.02 (d, 1H), 8.64 (d, 1H), 8.45 (m, 2H), 5.15 (t, 2H), 4.68 (t, 2H), 2.98 (s, 3H), 2.05 (m, 4H), 1.95 (m, 4H), 1.85 (s, 6H), 1.47 (m, 4H), 0.95 (m, 6H)

[Example 5 <Synthesis of Exemplary Compound A-25>]
Exemplary compound A-24: 126 mg (0.2 mmol) was dissolved in water. An aqueous solution in which 300 mg of potassium hexafluorophosphate was dissolved was added dropwise, and the mixture was stirred at room temperature for 3 hours. The precipitated crystals were filtered, washed successively with isopropyl alcohol and diethyl ether, and then recrystallized from acetonitrile/isopropyl alcohol to obtain 120 mg (yield: 90%) of exemplary compound A-25. The structure of this compound was confirmed by NMR measurement.
^1H NMR (DMSO- _d6 , 500MHz) σ (ppm): 9.83 (d, 1H), 9.66 (s, 1H), 9.23 (s, 1H), 9.02 (d, 1H), 8.64 (d, 1H), 8.45 (m, 2H), 5.15 (t, 2H), 4.68 (t, 2H), 2.98 (s, 3H), 2.05 (m, 4H), 1.95 (m, 4H), 1.85 (s, 6H), 1.47 (m, 4H), 0.95 (m, 6H)

[Example 6]
<Preparation of EC device>
Tetrabutylammonium perchlorate as an electrolyte was dissolved in propylene carbonate at a concentration of 0.1 M, and then exemplified compound A-31 of Example 3 was dissolved therein at a concentration of 40.0 mM to obtain an EC medium.

Next, an insulating layer (SiO ₂ ) was formed on the four ends of a pair of glass substrates with transparent conductive films (ITO). A PET film (Melinex S (registered trademark), 125 μm thick, manufactured by Teijin DuPont Films) that defines the substrate interval was placed between the pair of glass substrates with transparent electrode films. Thereafter, the substrate and the PET film were bonded and sealed with an epoxy adhesive, leaving an injection port for injecting the EC medium, to prepare an empty cell with an injection port. Next, the EC medium was injected from the injection port by vacuum injection, and the injection port was sealed with an epoxy adhesive to obtain an EC element.

Immediately after fabrication, the EC element exhibited a transmittance of approximately 80% across the entire visible light range, and had high transparency.

<Evaluation of EC device characteristics>
Figure 5 shows the ultraviolet-visible absorption spectrum of this element in the colored state and the decolorized state. An Ocean Optics DH-2000S deuterium/halogen light source was used as the light source. As shown in Figure 5, when a voltage of 2.0 V was applied to this element, the element exhibited absorption derived from the reduced species of Exemplified Compound A-31, and the element was colored. Furthermore, when a voltage of -0.5 V was applied to this element, the element was decolorized. This element can be reversibly changed between a colored state and a decolorized state.

[Example 7]
A device was prepared and evaluated in the same manner as in Example 6, except that Exemplary Compound A-22 was used instead of Exemplary Compound A-31. FIG. 6 shows the ultraviolet-visible absorption spectra of this device in the colored and decolored states. As shown in FIG. 6, when a voltage of 2.0 V was applied to this device, the device exhibited absorption derived from the reduced species of Exemplary Compound A-22, and was colored. Furthermore, when a voltage of −0.5 V was applied to this device, the device was decolored, and reversible coloring and decoloring were performed. This device can reversibly change between a colored state and a decolored state.

[Example 8]
An element was prepared and evaluated in the same manner as in Example 6, except that Exemplary Compound A-25 was used instead of Exemplary Compound A-31. FIG. 7 shows the ultraviolet-visible absorption spectra of this element in the colored and decolored states. As shown in FIG. 7, when a voltage of 2.0 V was applied to this element, the element exhibited absorption derived from the reduced species of Exemplary Compound A-25, and was colored. Furthermore, when a voltage of −0.5 V was applied to this element, the element was decolored, and reversible coloring and decoloring were performed. This element can reversibly change between a colored state and a decolored state.

REFERENCE SIGNS LIST 1 EC element 10 Transparent substrate 11 Transparent electrode 12 EC layer 13 Spacer

Claims (20)

An organic compound represented by the following general formula (1):

In general formula (1), _X1 and _X2 are each independently selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, and a substituted or unsubstituted aralkyl group.
R ₁ to R ₈ are each independently selected from a hydrogen atom and a substituent. The substituent represented by R ₁ to R ₈ is any one of a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.
R ₉ and R ₁₀ are either a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. 2. The organic compound according to claim 1, further comprising an anion A ₁ ^- and an anion A ₂ ^- . 3. The organic compound according to claim 2, wherein A ₁ ^- and A ₂ ^- are the same anion. 4. The organic compound according to claim 1, wherein the _X1 and the _X2 are alkyl groups. The organic compound according to claim 4 , wherein X ₁ and X ₂ are the same substituent. 6. The organic compound according to claim 1, wherein _R9 and _R10 are alkyl groups. 7. The organic compound according to claim 1, wherein all of R ₁ to R ₈ are hydrogen atoms. An electrochromic element having a pair of electrodes and an electrochromic layer disposed between the pair of electrodes,
An electrochromic device, wherein the electrochromic layer contains the organic compound according to claim 1 . The electrochromic element according to claim 8, characterized in that the electrochromic layer contains an electrochromic compound different from the organic compound. The electrochromic element according to claim 9, characterized in that the different electrochromic compound is any one of a phenazine-based compound, a metallocene-based compound, a phenylenediamine-based compound, and a pyrazoline-based compound. The electrochromic element according to any one of claims 8 to 10, characterized in that the electrochromic layer contains five or more types of electrochromic compounds. The electrochromic element according to any one of claims 8 to 11, characterized in that the electrochromic layer is a solution layer. The electrochromic element according to claim 12, characterized in that the solution layer contains a thickener. The electrochromic element according to claim 13, characterized in that the weight ratio of the thickener is 20 wt % or less when the weight of the electrochromic layer is 100 wt %. The electrochromic element according to any one of claims 12 to 14, characterized in that the viscosity of the solution layer is 150 cP or less. An optical filter comprising an electrochromic element according to any one of claims 8 to 15 and a transistor connected to the electrochromic element. A lens unit comprising the optical filter according to claim 16 and an imaging optical system having a plurality of lenses. An imaging device comprising the optical filter according to claim 16 and a light receiving element that receives light that has passed through the optical filter. A window material comprising the electrochromic element according to any one of claims 8 to 15 and a transistor connected to the electrochromic element. 16. An electrochromic mirror comprising: the electrochromic element according to claim 8; and a reflective member provided inside or outside the electrochromic element.

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