JP2008089705A - Electrochromic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrochromic device which is excellent in responsiveness, materializes high density coloring property with low voltage, and conducts a reversible coloring and discoloring display with excellent stability. <P>SOLUTION: The electrochromic device: which has a pair of electrode structures (a display electrode structure 11 and a counter electrode structure 12) comprising at least a transparent electrode formed on the supporting substrate 1, and disposed so as to make the transparent electrodes 2, 7 be opposite to each other while interposing an electrolyte layer 5 in between; which has a porous electrode 4, with a pyridine compound having at least one pyridine section adsorbed thereto, formed on the transparent electrode, wherein the pyridine compound has at least one pyridine section which is made to be a quaternary amine; and which conducts reversible coloring and discoloring with application of voltage to the pair of electrode structures, is provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrochromic device that is excellent in coloring efficiency and response speed, can form clear and sharp images, and is excellent in repeated durability.

In recent years, there has been a growing demand for display dye materials and display elements using the same that are bright and excellent in color purity, consume less power, and can be easily applied to full-color display. Conventionally, CRT, LCD, PDP Many proposals have been made on light-emitting elements such as ELD.
However, since the above-mentioned various conventional light-emitting elements are used in such a manner that the user looks directly at the light emission, there is a problem that visual fatigue is caused when browsing for a long time.
In addition, mobile devices such as mobile phones are often used outdoors, and there is also a problem that the visibility is deteriorated by canceling light emission under sunlight.
Furthermore, LCD is a technology that is especially in demand among light-emitting elements, and is used in various display applications such as large and small. However, LCD has a narrow viewing angle and is easy to see. There are issues to be improved.

By the way, regarding the reflective display element, various techniques have been proposed in the past due to an increase in demand for electronic paper.
For example, a reflective LCD or an electrophoretic method can be used.
As the reflective LCD, a GH type liquid crystal system using a dichroic dye, a cholesteric liquid crystal, and the like are known. These methods have the advantage of power saving because they do not use a backlight, compared to conventional light emitting LCDs, but they have a viewing angle dependency and low light reflection efficiency, so There is a problem that the screen becomes dark.
On the other hand, the electrophoresis method is a method that utilizes a phenomenon in which charged particles dispersed in a solvent move by an electric field, and has the advantage of low power consumption and no viewing angle dependency. However, in the case of performing full color, it is necessary to apply a juxtaposed mixing method using a color filter, so that there is a problem that the reflectance is lowered and the screen is inevitably darkened.

In recent years, a device using an electrochromic (hereinafter abbreviated as EC) element has been proposed for a light control mirror, a timepiece or the like of an automobile.
Display using an EC element does not require a polarizing plate or the like, has no viewing angle dependency, is a reflective type, has excellent visibility, has a simple structure, can be easily enlarged, and can be varied depending on the selection of materials. There is an advantage that a color tone can be displayed.

As a display device using a specific EC element, there is a proposal for a display device having a structure in which a semiconductor nanoporous layer is provided on at least one of a pair of transparent electrodes and an EC dye is supported on the semiconductor nanoporous layer. (For example, refer to Patent Documents 1 and 2.)
These display devices can be held in a static state just by forming an open circuit to block the movement of electrons between the electrodes and maintaining the oxidation-reduction state, so no power is required to maintain the display image and consumption It is excellent in that the power is extremely low.

JP 2003-248242 A JP 2003-270670 A

  However, in the above-mentioned conventionally proposed technology, a bipyridine compound called viologen is used as a reactive dye, and it is a future problem to improve display efficiency by reducing the coloring voltage. It was.

  In order to apply a bipyridine compound and achieve efficient color development at a lower voltage, a predetermined functional group is introduced to increase the amount of adsorption to the porous electrode, or an alkoxy group or a halogen group is introduced. In such a case, if the structure is such that electron donating and electron withdrawing substituents are directly introduced into the pyridine skeleton, hue shift or absorption in an inappropriate wavelength range may occur. This causes a problem that accurate control of hue becomes difficult.

  In addition, introduction of electron-donating and electron-withdrawing substituents tends to cause inhibition of molecular stacking and intramolecular distortion, which leads to inconveniences such as a decrease in color development efficiency. It is considered that there is a demand for the development of organic EC dyes that satisfy both the characteristics of performing simple control and performing efficient color development at a low voltage.

  Therefore, in the present invention, in view of the problems of the prior art as described above, a study on the chemical structure of the organic EC dye is performed, it has a high adsorptive capacity for the electrode, and further has excellent low-voltage color developability, The present invention also provides an electrochromic device that can be easily and reliably controlled in hue, has high color purity, can form a clear image, and is excellent in repeated durability.

  In the present invention, a pair of electrode structures (a display electrode structure and a counter electrode structure) in which at least a transparent electrode is formed on a support substrate are arranged with an electrolyte layer sandwiched so that the transparent electrodes face each other. And a porous electrode on which a pyridine compound having at least one pyridine moiety is adsorbed is formed on at least one transparent electrode of the pair of electrode structures. The pyridine compound has the following formula ( It is assumed that at least one pyridine moiety is quaternized aminated by the constituent moiety represented by 1) or formula (2), and a reversible color-decoloration is achieved by applying a voltage to the pair of electrode structures. An electrochromic device to be performed is provided.

The terminal phosphonic acid groups of the above formulas (1) and (2) are extremely excellent in adsorptivity to the porous electrode.
Since a naphthalene group or a biphenyl group is introduced to the pyridine moiety via an alkyl chain, color developability at a low voltage can be obtained.

  According to the present invention, an electrochromic display device having excellent response speed, low voltage driving, color development efficiency, high color purity, easy and reliable hue control, and capable of precise image control is obtained.

The electrochromic device of the present invention will be specifically described with reference to the drawings.
However, the present invention is not limited to the following examples, and a conventionally known configuration can be added as appropriate, and does not depart from the gist of the present invention.

FIG. 1 shows a schematic sectional view of an example of the electrochromic device of the present invention.
The electrochromic device 10 includes a display electrode structure 11 having a structure in which a transparent electrode 2 and a porous electrode 4 on which an organic EC dye 3 made of a pyridine compound described later is supported are provided on a support substrate 1, and a support substrate. A counter electrode structure 12 having a configuration in which a transparent electrode 7 and a porous electrode 8 on which an organic radical compound 13 described later is supported is disposed on the electrode 6 with the electrolyte layer 5 therebetween. ing.
Hereinafter, the components will be sequentially described.

The support substrates 1 and 6 are preferably made of a material having excellent heat resistance and high dimensional stability in the planar direction. Specifically, glass materials and transparent resins can be applied, but the present invention is not limited thereto. Absent.
Examples of the transparent resin include polyethylene terephthalate, polyethylene naphthalate, polyamide, polysulfone, polyether sulfone, polyether ether ketone, polyphenylene sulfide, polycarbonate, polyimide, polymethyl methacrylate, and polystyrene.

The transparent electrodes 2 and 7 are formed by laminating a transparent electrode layer on a predetermined transparent substrate.
Examples of the material for forming the transparent electrode layer include a mixture of In ₂ O ₃ and SnO ₂ , a so-called ITO film, and a film coated with SnO ₂ or In ₂ O ₃ .
Further, Sn, Sb, F, or the like may be doped into the ITO film or a film coated with SnO ₂ or In ₂ O ₃ , and other MgO, ZnO, or the like can be applied.

The porous electrodes 4 and 8 are preferably composed of a material having a large surface area in order to ensure a high supporting function of the organic EC dye described later. Examples thereof include a porous shape having fine pores on the surface and inside, a lot shape, a wire shape, a mesoporous shape, and an aggregated particle shape.
As a material for the porous electrodes 4 and 8, for example, a metal, an intrinsic semiconductor, an oxide semiconductor, a complex oxide semiconductor, an organic semiconductor, carbon, or the like can be applied.
Examples of the metal include Au, Ag, Pt, and Cu. Examples of the intrinsic semiconductor include Si, Ge, and Te. Examples of the oxide semiconductor include TiO ₂ , SnO ₂ , Fe ₂ O ₃ , SrTiO ₃ , WO ₃ , ZnO, ZrO ₂ , Ta ₂ O ₅ , Nb ₂ O ₅ , V ₂ O ₅ , In ₂ O ₃ , Examples thereof include CdO, MnO, CoO, TiSrO ₃ , KTiO ₃ , Cu ₂ O, sodium titanate, barium titanate, and potassium niobate.
Examples of the complex oxide semiconductor include SnO ₂ —ZnO, Nb ₂ O ₅ —SrTiO ₃ , Nb ₂ O ₅ —Ta ₂ O ₅ , Nb ₂ O ₅ —ZrO ₂ , Nb ₂ O ₅ —TiO ₂ , Ti _{-SnO 2, Zr-SnO 2,} Sb-SnO 2, Bi-SnO 2, in-SnO 2 and the like, in particular _{TiO 2, SnO 2, Sb-} SnO 2, in-SnO 2 are preferred.
Examples of the organic semiconductor include polythiophene, polypyrrole, polyacetylene, polyphenylene vinylene, and polyphenylene sulfide.

Next, the organic EC dye 3 will be described.
The organic EC dye 3 is assumed to be carried on the surface of the porous electrode 4 and the internal micropores. In the present invention, in particular, a pyridine compound having an adsorption site represented by the following formulas (1) and (2) Apply.

The site | part shown by said Formula (1), (2) has a phosphonic acid group in the terminal, and is excellent in the adsorptivity with respect to a porous electrode.
Since a naphthalene group or a biphenyl group is introduced to the pyridine moiety via an alkyl chain, color developability at a low voltage can be obtained.

  The structure of the pyridine compound of the organic EC dye having at least one adsorption site represented by the above formulas (1) and (2) is not particularly limited in the pyridine skeleton. What is shown in (9) is mentioned.

  In FIG. 1 for explaining the present example, the organic EC dye 3 for color display is shown to be supported only on the porous electrode 4 on the display electrode structure 11 side. The configuration is not limited to the example, and the porous electrode 8 on the counter electrode structure 12 side may be supported. However, in such a case, a material that reverses the oxidation / reduction reaction in the color development / decoloration reaction of the organic EC dye is applied.

Further, in the pyridine compounds represented by the above formulas (3) to (9), all pyridine sites constituting the quaternary amination are used, but the present invention is not limited to this example, and at least one of the pyridine sites. A quaternized can also be applied.
In order to chemically bond the adsorptive site to the nitrogen atom of pyridine for quaternary amination, a halogen compound (especially bromide, chloride, iodide) is required.
For example, the compound of the above formula (1) is obtained by reacting 4,4′-bis (bromomethyl) biphenyl of the following formula (10) with a compound of the following formula (11) in a predetermined solvent to convert the bromo group to diethyl. A phosphonated compound of formula (12) is obtained.

  With respect to the pyridine compound of the above formula (2), for example, 2,6-bis (bromomethyl) naphthalene of the following formula (13) is reacted with the compound of the above formula (11) in a predetermined solvent to obtain bromo A compound of the formula (14) having a structure in which the group is converted to diethylphosphonate is obtained.

In order to introduce the above formulas (1) and (2) into the pyridine compound as an adsorption site, the predetermined pyridine compound and the derivatives of the above formulas (1) and (2) are reacted in a predetermined solvent. This quaternizes the pyridine moiety.
For example, when the compound represented by the following formula (15) and the compound represented by the above formula (12) are reacted in a predetermined solvent, a compound represented by the following formula (16) is obtained and further reacted in hydrochloric acid. A compound of the above formula (3) is obtained.

Next, a method for supporting the organic EC dye composed of the pyridine compound on the porous electrode 4 will be described.
For example, conventionally known techniques such as a method of adsorbing on the surface of the porous electrode 4 and a method of chemically bonding the surface of the porous electrode and the organic EC dye can be applied.
Specifically, a dry process such as a vacuum deposition method, a coating method such as spin coating, an electric field deposition method, an electric field polymerization method, a natural adsorption method in which a supported compound solution is immersed, and the like can be applied. A method of chemically bonding an organic EC dye to the surface of the porous electrode is suitable.

As a natural adsorption method, a solution is prepared by dissolving a predetermined organic EC dye in a predetermined solvent, and a transparent substrate on which a porous electrode 4 that has been previously dried is formed is immersed, The method of apply | coating the solution which melt | dissolved organic EC pigment | dye to the porous electrode 4 is mentioned.
In this natural adsorption method, in order to reliably adsorb the organic EC dye to the porous electrode 4, it is necessary to introduce a functional group having adsorptivity into the chemical structure of the organic EC dye.
This functional group having adsorptivity is a phosphonic acid group at the terminal of the above formulas (1) and (2).

  Examples of the solvent for dissolving the organic EC dye include water, alcohol, acetonitrile, propionitrile, halogenated hydrocarbons, ethers, dimethyl sulfoxide, N, N-dimethylformamide, N-methylpyrrolidone, esters, Carbonates, ketones, hydrocarbons and the like can be applied. These may be used singly or may be mixed as appropriate.

The electrolyte layer 5 has a configuration in which a supporting electrolyte is dissolved in a solvent.
Examples of the supporting electrolyte include lithium salts such as LiCl, LiBr, LiI, LiBF ₄ , LiClO ₄ , LiPF ₆ , and LiCF ₃ SO ₃ , potassium salts such as KCl, KI, and KBr, and NaCl, NaI, NaBr, and the like. And tetraalkylammonium salts such as tetraethylammonium borofluoride, tetraethylammonium perchlorate, tetrabutylammonium borofluoride, tetrabutylammonium perchlorate, and tetrabutylammonium halide.
A known redox compound may be added to the electrolyte layer 5 as necessary. As the redox substance, for example, a ferrocene derivative, a tetracyanoquinodimethane derivative, a benzoquinone derivative, a phenylenediamine derivative, or the like can be applied.
As the solvent, a solvent that dissolves the supporting electrolyte and does not dissolve the organic EC dye described above is selected.
For example, it is appropriately selected from water, acetonitrile, dimethylformamide, propylene carbonate, dimethyl sulfoxide, propylene carbonate and the like.

Further, a so-called matrix material may be applied to the electrolyte layer 5.
Matrix material can be appropriately selected depending on the purpose, for example, skeletal unit _{respectively, - (CC-O) n} -, - (CC (CH 3) -O) n -, - (CC-N ) _n- , or-(C-C-S) _n- , for example, polyethylene oxide, polypropylene oxide, polyethyleneimine, and polyethylene sulfide.
In addition, you may have a branched structure suitably by making these into a principal chain structure. Polymethyl methacrylate, polyvinylidene fluoride, polyvinylidene chloride, polycarbonate, and the like are also suitable.

The electrolyte layer 5 may be a polymer solid electrolyte layer.
In this case, it is preferable to add a predetermined plasticizer to the polymer of the matrix material.
As the plasticizer, when the matrix polymer is hydrophilic, water, ethyl alcohol, isopropyl alcohol, and a mixture thereof are preferable. When the matrix polymer is hydrophobic, propylene carbonate, dimethyl carbonate, ethylene carbonate, γ- Preferred are butyrolactone, acetonitrile, sulfolane, dimethoxyethane, ethyl alcohol, isopropyl alcohol, dimethylformamide, dimethyl sulfoxide, dimethylacetamide, n-methylpyrrolidone, and mixtures thereof.

Next, a display method using the electrochromic device 10 of the present invention will be described.
In the electrochromic device 10 of FIG. 1, the surface of the porous electrode 4 carries a pyridine compound represented by the formula (1), which is an organic EC dye that does not absorb in the visible region in a steady state.
A predetermined lead wire is connected to the pair of electrode structures 11 and 12 constituting the electrochromic device 10 to constitute a display device.
When a predetermined voltage is applied through a predetermined lead wire, electrons are transferred between the porous electrode 4 and the organic EC dye material carried on the porous electrode 4, and an electrochemical reduction reaction occurs in the organic EC dye, resulting in radicals. Colored as a condition.

The electrochromic device of the present invention is not limited to the so-called monochromatic display configuration shown in FIG. 1, and can be applied to a multicolor display configuration.
That is, an organic EC having the same structure as the electrochromic structure shown in FIG. 1 and having a radical state due to an electrochemical reaction and developing colors of magenta (M), cyan (C), and yellow (Y). By applying a dye and carrying it on a porous electrode to produce an electrode structure, and using these three layers, a laminated structure of magenta (M), yellow (Y), and cyan (C) is obtained. As a result, a full color display electrochromic device capable of reversibly performing color generation and decoloration display is obtained.

  Next, specific examples of the electrochromic device of the present invention and a comparative example thereof will be described.

(Synthesis of Organic EC Dye Compound: Formula (8) above)
5.0 g of 4,4′-bis (bromomethyl) biphenyl and 2.88 g of triethylphosphine were refluxed in 100 ml of toluene for 24 hours. Thereafter, the solvent was removed, the mixture was stirred with a mixed solvent of chloroform and water, and a chloroform solution was collected. This solution was dried over magnesium sulfate and the solvent was removed. Next, vacuum distillation was performed at 150 ° C. and 2 Torr.
Next, silica column chromatography was performed using chloroform as the developing solvent to obtain a diethylphosphonate compound.
6.20 g of the compound obtained as described above and 1.0 g of 1,4-di (4-pyridyl) benzene were refluxed for 24 hours in 50 ml of ethanol. After the reaction, the solvent was removed, and acetone was added to precipitate crystals. Next, the crystals were dissolved in hydrochloric acid and refluxed for 24 hours. After the reaction, hydrochloric acid was removed, IPA was added while cooling to precipitate crystals, and this was collected by filtration to obtain a pyridine compound represented by the above formula (8).

(Synthesis of Organic EC Dye Compound: Formula (9) above)
2,6-bis (bromomethyl) naphthalene (5.0 g) and triethylphosphine (2.64 g) were refluxed in 100 ml of toluene for 24 hours. Thereafter, the solvent was removed, the mixture was stirred with a mixed solvent of chloroform and water, and a chloroform solution was collected. This solution was dried over magnesium sulfate and the solvent was removed. Next, vacuum distillation was performed at 150 ° C. and 2 Torr.
Next, silica column chromatography was performed using chloroform as the developing solvent to obtain a diethylphosphonate compound.
6.0 g of the compound obtained as described above and 1.0 g of 1,4-di (4-pyridyl) benzene were refluxed for 24 hours in 50 ml of ethanol. After the reaction, the solvent was removed, and acetone was added to precipitate crystals. Next, the crystals were dissolved in hydrochloric acid and refluxed for 24 hours. After the reaction, hydrochloric acid was removed, IPA was added while cooling to precipitate crystals, and this was collected by filtration to obtain the pyridine compound represented by the above formula (9).

(Preparation of display electrode structure)
On a support substrate 1 made of glass having a thickness of 1.1 mm, a 15 Ω / □ FTO film (transparent electrode 2) was formed in a plane.
Next, polyethylene glycol was dissolved at a rate of 5% by weight in a slurry in which 15% by weight of titanium oxide having a primary particle diameter of 20 nm was dispersed in an aqueous hydrochloric acid solution having a pH of about 1.0 to prepare a coating material. This paint was applied on the FTO film by a squeegee method.
Next, an FTO substrate on which a titanium oxide porous electrode 4 having a film thickness of 3 μm is formed by performing a drying process at 80 ° C. for 15 minutes on a hot plate, further sintering at 500 ° C. for 1 hour in an electric furnace. Obtained.
The FTO substrate on which the porous electrode 4 made of the titanium oxide film is formed is immersed in a 5 mM aqueous solution of the predetermined pyridine compound prepared as described above for 24 hours to adsorb the organic EC dye on the titanium oxide porous electrode 4 I let you.
Thereafter, washing treatment and drying treatment were performed with an ethanol solution.

(Preparation of counter electrode structure)
On a support substrate 6 made of glass having a thickness of 1.1 mm, a 15Ω / □ FTO film (transparent electrode 7) was formed in a plane.
Next, polyethylene glycol was dissolved at a ratio of 5% by weight in a slurry in which 20% by weight of antimony-doped tin oxide having a primary particle diameter of 20 nm was dispersed in an acidic aqueous solution to prepare a paint. This paint was applied on the FTO film by a squeegee method.
Next, the FTO was dried on a hot plate at 80 ° C. for 15 minutes, further sintered in an electric furnace at 500 ° C. for 1 hour, and an antimony-doped tin oxide porous electrode 8 having a thickness of 12 μm was formed. A substrate was obtained.

(Preparation of solution for electrolyte layer)
As the electrolyte layer 5 forming solution, a solution obtained by dissolving 0.1 mol / L of lithium perchlorate in gamma-butyrolaclone, dehydrating and degassing was applied.

(Lamination of electrode structure)
Adhesion of display electrode structure (substrate with dye-adsorbed titanium oxide porous electrode) and counter electrode structure (substrate with antimony-doped tin oxide porous electrode) produced as described above to a thermoplastic film having a thickness of 50 μm Using an agent, bonding was performed at 90 ° C.
At this time, an injection port was formed in a part so that the electrolyte solution could be injected by a process described later.

(Injection of electrolyte solution)
The electrolytic solution was injected from the injection port.
Thereafter, the injection port was sealed with an epoxy-based thermosetting resin, thereby completing an electrochromic device including electrode structures facing each other with the electrolyte layer sandwiched therebetween.
In accordance with the manufacturing process of the electrochromic device described above, different organic EC dyes supported on the porous electrode were applied to prepare sample cells of the following examples and comparative examples.

[Preparation of Example Sample]
As the organic EC dye, the compounds of the above formulas (8) and (9) were applied and adsorbed to the porous electrode constituting the display electrode structure, thereby producing the electrochromic device shown in FIG.
When a voltage of −1.3 V was applied between the display electrode and the counter electrode of the electrochromic device using the above formulas (8) and (9), a brown color was immediately developed. Color development spectra at this time are shown in FIGS. 2 and 3, respectively.
The response speed of the display change is 100 to 130 ms, which is a sufficiently good speed for practical use.
When 0.5 V was applied between the electrodes, it became transparent again immediately. The response speed of the display change was 60 to 80 ms.
Further, when -1.3 V and 0.5 V were alternately applied 1 million times at 1 Hz between the display electrode and the counter electrode, the initial state and the spectral shape were maintained even after the voltage application was repeated 1 million times. Almost no change was observed, and it was confirmed that the material had sufficiently excellent durability for practical use.
As described above, according to the electrochromic device of the present invention, it was possible to perform clear color tone display while maintaining excellent durability with low voltage driving.

[Production of Comparative Sample]
As organic EC dyes, compounds represented by the following formulas (17) and (18) are prepared, and these are respectively supported on the porous electrodes of the display electrode structure to produce an electrochromic device in the same manner as in the above examples. Evaluation of color development was performed.

In the electrochromic device using the organic EC dye of the above formula (17), when a voltage of −1.3 V was applied between both electrodes, sufficient color development was not obtained. On the other hand, when a voltage of -1.5 V was applied, color development with the same density as in the above example was confirmed.
FIG. 4 shows a color development spectrum when a voltage of −1.3 V is applied between the electrodes of the electrochromic device to which the organic EC dye of the formula (17) is applied.
As is clear from a comparison between FIGS. 2 and 3 and FIG. 4, it was confirmed that according to the present invention, it is possible to perform color development at a low voltage.
It was confirmed that the compound of formula (17) does not have low potential drivability because the substituent having the quaternized pyridine moiety does not have a ring structure.

In the electrochromic device using the organic EC dye of the formula (18), when a voltage of −1.3 V was applied between both electrodes, a brown color was obtained. The color development spectrum at this time is shown in FIG.
Comparing FIG. 5 with FIGS. 2 and 3, it can be seen that FIG. 5 is inferior in color density even when the same voltage is applied. This is because the compound of formula (18) has a carboxyl group at the end, which is inferior in the adsorptivity to the porous electrode as compared with the phosphonic acid group.
From this, it was confirmed that according to the electrochromic device of the above example, high density color development was obtained at a low voltage.

  As is clear from the above, the response by applying the pyridine compound having the adsorptive group represented by the above formulas (1) and (2) as the organic EC dye supported on the porous electrode constituting the electrode structure. Excellent reaction, high color density at low voltage, and reversible color display with excellent stability.

1 shows a schematic cross-sectional view of an example of an electrochromic device of the present invention. The visible absorption spectrum at the time of color development at the time of applying the compound of a formula (8) is shown. The visible absorption spectrum at the time of color development at the time of applying the compound of a formula (9) is shown. The visible absorption spectrum at the time of color development at the time of applying the compound of a formula (17) is shown. The visible absorption spectrum at the time of color development at the time of applying the compound of a formula (18) is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,6 ... Support substrate, 2 ... Transparent electrode, 3 ... Organic EC pigment | dye, 4,8 ... Porous electrode, 5 ... Electrolyte layer, 10 ... Electrochromic device, 11 ... Display electrode structure , 12 ... Counter electrode structure

Claims (2)

A pair of electrode structures (a display electrode structure and a counter electrode structure) in which at least a transparent electrode is formed on a support substrate are arranged with an electrolyte layer sandwiched so that the transparent electrodes face each other,
A porous electrode on which a pyridine compound having at least one pyridine moiety is adsorbed is formed on at least one transparent electrode of the pair of electrode structures,
In the pyridine compound, at least one pyridine moiety is quaternized with a component represented by the following formula (1) or (2):
An electrochromic device that performs reversible color development by applying a voltage to the pair of electrode structures.

  2. The electrochromic device according to claim 1, wherein the porous electrode is formed of a metal, a semiconductor material, or a conductive polymer having a mesoporous shape, an aggregated particle shape, a lot shape, or a wire shape.

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