JPWO2009147924A1 - Display element and manufacturing method thereof - Google Patents

Abstract

The present invention provides a display element capable of realizing bright white display, high-contrast black-and-white display, and full-color display with a simple member configuration and having a high display speed, and a method for manufacturing the same. This display element has an electrolyte layer containing at least an electrolyte between a pair of counter electrodes, and at least one of the counter electrodes is a display side electrode formed by laminating a conductive layer and a porous layer, and the display side A display element in which an electrochromic compound is fixed to a part of an electrode, wherein the display side electrode forms a coating layer that inhibits the fixing of the electrochromic compound on the part, and then the electrochromic compound is fixed It is characterized by being.

Description

  The present invention relates to a novel electrochemical display element and a method for manufacturing the same.

  In recent years, with the increase in the operating speed of personal computers, the spread of network infrastructure, the increase in capacity and price of data storage, information such as documents and images provided on printed paper on paper has become easier to use electronic information. Opportunities to obtain and browse electronic information are increasingly increasing.

  As such electronic information browsing means, conventional liquid crystal displays and CRTs, and in recent years, light-emitting types such as organic EL displays are mainly used. Particularly, when electronic information is document information, it is relatively long time. It is necessary to pay close attention to this browsing means, and these actions are not necessarily human-friendly means. Generally, as a drawback of light-emitting displays, eyes flicker due to flickering, inconvenient to carry, reading posture is limited It is known that it is necessary to adjust the line of sight to a still screen, and that power consumption increases when read for a long time.

  As a display means to compensate for these drawbacks, a reflective display having a so-called “memory property” that uses external light and does not consume power for image retention is known. However, it has sufficient performance for the following reasons. It ’s hard to say.

  That is, the method using a polarizing plate such as a reflective liquid crystal has a low reflectance of about 40%, which makes it difficult to display white, and it is difficult to say that many of the manufacturing methods used to manufacture the constituent members are simple. In addition, the polymer dispersed liquid crystal requires a high voltage and utilizes the difference in refractive index between organic substances, so that the resulting image has insufficient contrast. In addition, the polymer network type liquid crystal has problems such as a high voltage and a need for a complicated TFT circuit to improve the memory performance. In addition, a display element based on electrophoresis requires a high voltage of 10 V or more, and there is a concern about durability due to electrophoretic particle aggregation.

  As a display method for solving the disadvantages of each of the above-mentioned methods, there are an electrochromic display element (hereinafter abbreviated as EC method) and an electrodeposition method (hereinafter abbreviated as ED method) using dissolution precipitation of metal or metal salt. Are known. The EC method has the advantage of being capable of full color display at a low voltage of about 3V or less, and having a simple cell configuration and excellent white quality. The ED method can also be driven at a low voltage of 3V or less and is simple. There are advantages such as excellent cell configuration, black and white contrast and black quality, and various methods have been disclosed (see, for example, Patent Documents 1 to 5).

  However, in the EC method, there is a problem that the display speed is lowered when the fixing density of the electrochromic compound is increased in order to increase the coloring density. In particular, in order to promote the electrochemical reaction of the electrochromic material, it is remarkable when an auxiliary compound that can be oxidized and reduced (hereinafter referred to as a promoter) is added to the electrolytic solution in addition to the EC compound. It is considered that the coloring rate of the electrochromic compound is reduced as a result of the increased fixation density of the compound, which makes it difficult for the promoter to approach the electrode and suppresses the redox reaction of the promoter.

  The present inventor has also examined a display element (hereinafter, abbreviated as ED + EC system) that displays an electrochromic compound in the ED display element and performs color display other than black and white in addition to white display and black display. Display elements having many advantages such as being capable of realizing bright white display, high contrast black and white display and full color display with a simple member configuration. However, in order to increase the color density when performing color display other than black and white, increasing the fixed density of the electrochromic compound not only decreases the rewrite speed of color display other than black and white but also decreases the rewrite speed of black and white. There was a problem. This is because the fixing density of the electrochromic compound on the electrode surface is increased, so that not only the redox reaction of the promoter but also the dissolution and precipitation reaction of the metal or metal salt is suppressed, so the black-and-white rewriting speed is reduced. Yes.

International Publication No. 04/068231 Pamphlet International Publication No. 04/066733 Pamphlet U.S. Pat. No. 4,240,716 Japanese Patent No. 3428603 JP 2003-241227 A JP 2003-270670 A

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a display element capable of realizing bright white display, high-contrast black-and-white display, and full-color display with a simple member configuration and having a high display speed. It is in providing the manufacturing method.

  The above object of the present invention is achieved by the following configurations.

  1. An electrolyte layer containing at least an electrolyte is provided between a pair of counter electrodes, and at least one of the counter electrodes is a display side electrode formed by laminating a conductive layer and a porous layer, and a part of the display side electrode A display element to which an electrochromic compound is fixed, wherein the display side electrode is formed by forming a coating layer that inhibits the fixing of the electrochromic compound on a part thereof, and then fixing the electrochromic compound. A display element.

  2. 2. The display element according to 1 above, wherein the covering layer is formed by forming an electrochemically deposited and / or soluble substance as a covering layer.

  3. 3. The display element according to 1 or 2, wherein the display-side electrode is obtained by fixing the electrochromic compound and further dissolving the coating layer.

  4). 4. The display element according to any one of items 1 to 3, wherein the coating layer is made of metal.

  5. 5. The electrolyte layer according to any one of 1 to 4, wherein the electrolyte layer further contains a metal salt compound, and performs a black display, a white display, or a color display other than black by driving the counter electrode. Display element.

  6). 6. The display element according to 5 above, wherein the coating layer is made of metal, and the metal of the coating layer is made of the same element as the metal of the metal salt compound.

  7). 7. The display element as described in 5 or 6 above, wherein the metal salt compound is a silver salt compound.

  8). 8. The display element according to any one of 1 to 7, wherein the electrochromic compound is fixed to a display side electrode through a silanol bond.

  9. 9. The display element according to any one of 1 to 8, wherein the electrochromic compound is a compound represented by the following general formula (L).

(Wherein Rl ₁ represents a substituted or unsubstituted aryl group, Rl ₂ and Rl ₃ each represent a hydrogen atom or a substituent, X represents> N-Rl ₄ , an oxygen atom or a sulfur atom, and Rl ₄ Represents a hydrogen atom or a substituent.)
10. An electrolyte layer containing at least an electrolyte between a pair of counter electrodes, and at least one of the counter electrodes is a display side electrode formed by laminating a conductive layer and a porous layer, and the display side electrode is electrochromic compound A method of manufacturing a display element in which at least a part of the display element is fixed, wherein the coating layer inhibits fixing of the electrochromic compound to a part of the display-side electrode by an electrochemical method by applying a voltage to the conductive layer And then fixing the electrochromic compound to the display-side electrode.

  According to the present invention, a bright white display, a high-contrast black and white display, and a full color display can be realized with a simple member configuration, and a display element having a high display speed and a manufacturing method thereof can be provided.

It is a schematic diagram which shows the fixing method to the electrode of an electrochromic compound. It is another schematic diagram which shows the fixing method to the electrode of an electrochromic compound.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  As a result of intensive studies in view of the above problems, the present inventor has an electrolyte layer containing at least an electrolyte between a pair of counter electrodes, and at least one of the counter electrodes is formed by laminating a conductive layer and a porous layer. A display element in which an electrochromic compound is fixed to a part of the display side electrode, and the display side electrode has a coating layer that inhibits the fixing of the electrochromic compound on a part of the display side electrode. It was found that bright white display, high-contrast black and white display and full color display can be realized with a simple member configuration and a display device with a high display speed can be obtained by a display element formed and then fixed with an electrochromic compound. It is up to the invention.

  Details of the display element of the present invention will be described below.

[Basic structure of display element]
In the display element of the present invention, the display portion is provided with a pair of electrodes facing each other. As an example, there is a configuration in which one is a display side electrode formed by laminating a transparent conductive layer such as ITO and a porous layer such as TiO ₂ and the other is a counter electrode made of a metal such as silver. A coating layer is deposited on a part of the display side electrode by an electrochemical method by applying a voltage to the conductive layer, and the electrochromic compound is fixed to the display side electrode. An electrolyte is held between a pair of electrodes, and by applying a voltage of both positive and negative polarities between the electrodes, an oxidation-reduction reaction of the electrochromic compound fixed to the display side electrode is performed, and transparent or colored The state can be switched reversibly. Furthermore, when a metal salt compound is contained in the electrolyte, a redox reaction of the metal salt compound is also performed on the display side electrode and the counter electrode, and the reduced state black and the oxidized state transparent can be switched reversibly. .

〔electrode〕
In the display element of the present invention, it is preferable that at least one of the pair of counter electrodes is a metal electrode. As the metal electrode, for example, known metal species such as platinum, gold, silver, copper, aluminum, zinc, nickel, titanium, bismuth, and alloys thereof can be used. The metal electrode is preferably a metal having a work function close to the redox potential of silver in the electrolyte. Among them, silver or a silver electrode having a silver content of 80% or more is advantageous for maintaining the reduced state of silver. Excellent in preventing dirt. As an electrode manufacturing method, an existing method such as an evaporation method, a printing method, an ink jet method, a spin coating method, or a CVD method can be used.

  In addition, in the display element of the present invention, one of the preferable features is that, among the pair of counter electrodes, the electrode to which the electrochromic compound is fixed is a porous electrode in which a transparent conductive layer and a porous layer are laminated.

  The transparent conductive layer is not particularly limited as long as it is transparent and conducts electricity. For example, Indium Tin Oxide (ITO: Indium Tin Oxide), Indium Zinc Oxide (IZO: Indium Zinc Oxide), Fluorine Doped Tin Oxide (FTO), Indium Oxide, Zinc Oxide, Platinum, Gold, Silver, Rhodium, Copper, Examples thereof include chromium, carbon, aluminum, silicon, amorphous silicon, and BSO (Bismuth Silicon Oxide). In order to form the electrode in this manner, for example, an ITO film may be vapor-deposited on the substrate by a sputtering method or the like, or an ITO film may be formed on the entire surface and then patterned by a photolithography method. The surface resistance value is preferably 100Ω / □ or less, and more preferably 10Ω / □ or less. The thickness of the transparent electrode is not particularly limited, but is generally 0.1 to 20 μm.

  As a method for forming the porous layer, a dispersion containing the material constituting the electrode is formed into a layer containing the material constituting the electrode and the solvent by an inkjet method, a screen printing method, a blade coating method, etc. Examples include a method of making porous by heating at 300 ° C., and a method of making porous by anodizing and photoelectrochemical etching after forming an electrode layer by sputtering, CVD, atmospheric pressure plasma, or the like. It is done. Also, Adv. Mater. , 2006, 18, 2980-2983, the porous layer can also be formed.

The main components of the material constituting the porous layer according to the present invention are metals such as Cu, Al, Pt, Ag, Pd, and Au, metal oxides such as ITO, SnO ₂ , TiO ₂ , and ZnO, carbon nanotubes, and glassy It can be selected from carbon electrodes such as carbon, diamond-like carbon, and nitrogen-containing carbon, and is preferably selected from metal oxides such as ITO, SnO ₂ , TiO ₂ , and ZnO.

  Porous as used in the present invention refers to a porous electrode that is sandwiched between other electrodes after the electrolyte is applied, a potential difference is applied between the counter electrodes, and the ionic species contained in the electrolyte is porous. This means a state in which the electrode can move.

  The film thickness of the porous electrode according to the present invention is preferably in the range of 100 to 1500 nm, more preferably in the range of 250 to 1000 nm.

〔Electrolytes〕
The term “electrolyte” as used in the present invention generally refers to a substance that dissolves in a solvent such as water and exhibits ionic conductivity in a solution (hereinafter referred to as “narrowly defined electrolyte”). A mixture containing other metals, compounds, or the like, regardless of whether it is an electrolyte or a non-electrolyte, is called an electrolyte (“broadly defined electrolyte”).

[Supporting electrolyte]
As the supporting electrolyte used in the present invention, salts, acids, and alkalis that are usually used in the field of electrochemistry or the field of batteries can be used.

  There is no restriction | limiting in particular as salts, For example, inorganic ion salts, such as an alkali metal salt and alkaline-earth metal salt; Quaternary ammonium salt; Cyclic quaternary ammonium salt; Quaternary phosphonium salt etc. can be used.

Specific examples of the salts include halogen ions, SCN ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , PF Li salt, Na salt having a counter anion selected from ₆ ⁻ , AsF ₆ ⁻ , CH ₃ COO ⁻ , CH ₃ (C ₆ H ₄ ) SO ₃ ⁻ , and (C ₂ F ₅ SO ₂ ) ₃ C ⁻ K salt is mentioned.

Further, halogen ions, SCN ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , PF ₆ ⁻ , AsF _{6 ^{-, CH 3 COO -, CH}} 3 (C 6 H 4) SO 3 -, and _{(C 2 F 5 SO 2)} 3 C - 4 quaternary ammonium salt having a counter anion selected from, specifically, (CH ₃ ) ₄ NBF ₄ , (C ₂ H ₅ ) ₄ NBF ₄ , (n-C ₄ H ₉ ) ₄ NBF ₄ , (C ₂ H ₅ ) ₄ NBr, (C ₂ H ₅ ) ₄ NClO ₄ , (n- C ₄ H ₉ ) ₄ NClO ₄ , CH ₃ (C ₂ H ₅ ) ₃ NBF ₄ , (CH ₃ ) ₂ (C ₂ H ₅ ) ₂ NBF ₄ , (CH ₃ ) ₄ NSO ₃ CF ₃ , (C ₂ H _{5) 4 NSO 3 CF 3,} (n-C 4 H 9) ₄ NSO ₃ CF ₃ , and a compound represented by the following formula can be given.

Also, halogen ions, SCN ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , PF ₆ ⁻ , AsF ₆ ⁻ , A phosphonium salt having a counter anion selected from CH ₃ COO ⁻ , CH ₃ (C ₆ H ₄ ) SO ₃ ⁻ , and (C ₂ F ₅ SO ₂ ) ₃ C ^— , specifically, (CH ₃ ) _{4 PBF 4, (C 2 H 5} ) 4 PBF 4, (C 3 H 7) 4 PBF 4, include _{(C 4 H 9) 4 PBF} 4 and the like. Moreover, these mixtures can also be used suitably.

The supporting electrolyte used in the present invention is preferably a cyclic quaternary ammonium salt, particularly preferably a quaternary spiro ammonium salt. The _ClO ⁴ as counter anion ^{_{-, BF 4 -, CF 3}} SO 3 -, (C 2 F 5 SO 2) 2 N -, PF 6 - are preferable, and BF ₄ ^- is preferable.

  The amount of the electrolyte salt used is arbitrary, but generally, the electrolyte salt is present in the solvent as an upper limit of 20 mol / l or less, preferably 10 mol / l or less, more preferably 5 mol / l or less. Desirably, the lower limit is usually 0.01 mol / l or more, preferably 0.05 mol / l or more, more preferably 0.1 mol / l or more.

  In the case of a solid electrolyte, the following compounds showing electron conductivity and ion conductivity can be contained in the electrolyte.

Vinyl fluoride polymer containing perfluorosulfonic acid, polythiophene, polyaniline, polypyrrole, triphenylamines, polyvinylcarbazoles, polymethylphenylsilanes, Cu ₂ S, Ag ₂ S, Cu ₂ Se, AgCrSe _2, etc. Chalcogenide, CaF ₂ , PbF ₂ , SrF ₂ , LaF ₃ , TlSn ₂ F ₅ , CeF _{3 and} other F-containing compounds, Li ₂ SO ₄ , Li ₄ SiO ₄ , Li ₃ PO _{4 and} other Li salts, ZrO ₂ , CaO , Cd ₂ O 3, HfO ₂ , Y ₂ O ₃ , Nb ₂ O ₅ , WO ₃ , Bi ₂ O ₃ , AgBr, AgI, CuCl, CuBr, CuBr, CuI, LiI, LiBr, LiCl, LiAlCl ₄ , LiAlF ₄ , _{AgSBr, C 5 H 5 NHAg 5} I 6, Rb 4 Cu 16 I 7 _{l 13, Rb 3 Cu 7 Cl} 10, LiN, compounds such as _{Li 5 N I2, Li 6 NBr} 3 , and the like.

[Metal salt compounds]
The metal salt compound according to the present invention is any compound as long as it contains a metal species that can be dissolved and precipitated by driving the counter electrode on at least one electrode on the counter electrode. There may be. Preferred metal species are silver, bismuth, copper, nickel, iron, chromium, zinc and the like, more preferred are silver and bismuth, and particularly preferred is silver.

[Silver salt compound]
The silver salt compound according to the present invention is silver or a compound containing silver in the chemical structure, such as silver oxide, silver sulfide, metallic silver, silver colloidal particles, silver halide, silver complex compound, silver ion and the like. There are no particular restrictions on the phase state species such as the solid state, the solubilized state in liquid, and the gas state, and the charged state species such as neutral, anionic, and cationic.

  In the display element of the present invention, silver iodide, silver chloride, silver bromide, silver oxide, silver sulfide, silver citrate, silver acetate, silver behenate, silver p-toluenesulfonate, silver trifluoromethanesulfonate, mercapto A known silver salt compound such as a silver salt with an acid or a silver complex with iminodiacetic acid can be used. Among these, it is preferable to use, as a silver salt, a compound that does not have a nitrogen atom having coordination properties with halogen, carboxylic acid, or silver, and for example, silver p-toluenesulfonate is preferable.

  The metal ion concentration contained in the electrolyte according to the present invention is preferably 0.2 mol / kg ≦ [Metal] ≦ 2.0 mol / kg. If the metal ion concentration is 0.2 mol / kg or more, a silver solution having a sufficient concentration can be obtained, and a desired driving speed can be obtained. If the metal ion concentration is 2 mol / kg or less, precipitation is prevented, and storage at low temperature is possible. The stability of the electrolyte solution is improved.

[Halogen ion, metal ion concentration ratio]
In the display element of the present invention, the molar concentration of halogen ions or halogen atoms contained in the electrolyte is [X] (mol / kg), and silver contained in the electrolyte or the total silver of the compound containing silver in the chemical structure. When the molar concentration is [Metal] (mol / kg), it is preferable to satisfy the condition defined by the following formula (1).

Formula (1): 0 ≦ [X] / [Metal] ≦ 0.1
In the present invention, the halogen atom means an iodine atom, a chlorine atom, a bromine atom, or a fluorine atom. When [X] / [Metal] is greater than 0.1, X ⁻ → X ₂ is generated during the oxidation-reduction reaction of the metal, and X ₂ easily cross-oxidizes with the deposited metal to dissolve the deposited metal. Therefore, the molar concentration of halogen atoms is preferably as low as possible relative to the molar concentration of metallic silver. In the present invention, 0 ≦ [X] / [Metal] ≦ 0.001 is more preferable. In the case of adding halogen ions, the halogen species preferably have a total molar concentration of [I] <[Br] <[Cl] <[F] from the viewpoint of improving memory properties.

[Silver salt solvent]
In the present invention, a silver salt solvent can be used to promote dissolution and precipitation of metal salts (particularly silver salts). The silver salt solvent may be any compound that can solubilize silver in the electrolyte. For example, solubilize silver or a compound containing silver by coexisting with a compound containing a chemical structural species that interacts with silver, such as a coordinate bond with silver or a weak supply bond with silver. It is common to use a means for converting to an object. As the chemical species, halogen atoms, mercapto groups, carboxyl groups, imino groups and the like are known, but in the present invention, compounds containing thioether groups and mercaptoazoles are useful as silver solvents, and It is characterized by low influence on coexisting compounds and high solubility in solvents.

  In particular, it is preferable to contain at least one compound represented by the following general formula (G1) or general formula (G2).

[Compound represented by General Formula (G1) or General Formula (G2)]
General Formula _{(G1) Rg 11 -S-Rg} 12
In the formula, Rg ₁₁ and Rg ₁₂ each represent a substituted or unsubstituted hydrocarbon group, and these include an aromatic linear group or a branched group. These hydrocarbon groups may contain one or more nitrogen atoms, oxygen atoms, phosphorus atoms, sulfur atoms, and halogen atoms, and Rg ₁₁ and Rg ₁₂ may be linked to each other to take a cyclic structure. However, when a ring containing an S atom is formed, an aromatic group is not taken.

  Examples of groups that can be substituted for the hydrocarbon group include amino groups, guanidino groups, quaternary ammonium groups, hydroxyl groups, halogen compounds, carboxylic acid groups, carboxylate groups, amide groups, sulfinic acid groups, sulfonic acid groups, and sulfates. Groups, phosphonic acid groups, phosphate groups, nitro groups, cyano groups and the like.

  Specific examples of the compound represented by the general formula (G1) according to the present invention are shown below, but the present invention is not limited only to these exemplified compounds.

G1-1: CH ₃ SCH ₂ CH ₂ OH
G1-2: HOCH ₂ CH ₂ SCH ₂ CH ₂ OH
G1-3: HOCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ OH
G1-4: HOCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ OH
G1-5: HOCH ₂ CH ₂ SCH ₂ CH ₂ OCH ₂ CH ₂ OCH ₂ CH ₂ SCH ₂ CH ₂ OH
_{G1-6: HOCH 2 CH 2 OCH 2} CH 2 SCH 2 CH 2 SCH 2 CH 2 OCH 2 CH 2 OH
G1-7: H ₃ CSCH ₂ CH ₂ COOH
G1-8: HOOCCH ₂ SCH ₂ COOH
G1-9: HOOCCH ₂ CH ₂ SCH ₂ CH ₂ COOH
G1-10: HOOCCH ₂ SCH ₂ CH ₂ SCH ₂ COOH
G1-11: HOOCCH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ COOH
G1-12: HOOCCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH (OH) CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ COOH
G1-13: HOOCCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH (OH) CH (OH) CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ COOH
G1-14: H ₃ CSCH ₂ CH ₂ CH ₂ NH ₂
G1-15: H ₂ NCH ₂ CH ₂ SCH ₂ CH ₂ NH ₂
G1-16: H ₂ NCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ NH ₂
G1-17: H ₃ CSCH ₂ CH ₂ CH (NH ₂ ) COOH
G1-18: H ₂ NCH ₂ CH ₂ OCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ OCH ₂ CH ₂ NH _{2
G1-19: H 2 NCH 2 CH 2} SCH 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 SCH 2 CH 2 NH 2
G1-20: H ₂ NCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ NH ₂
G1-21: HOOC (NH ₂ ) CHCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ CH (NH ₂ ) COOH
G1-22: HOOC (NH ₂ ) CHCH ₂ SCH ₂ CH ₂ OCH ₂ CH ₂ OCH ₂ CH ₂ SCH ₂ CH (NH ₂ ) COOH
G1-23: HOOC (NH ₂ ) CHCH ₂ OCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ OCH ₂ CH (NH ₂ ) COOH
_{G1-24: H 2 N (O =} ) CCH 2 SCH 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 SCH 2 C (= O) NH 2
_{G1-25: H 2 N (O =} ) CCH 2 SCH 2 CH 2 SCH 2 C (= O) NH 2
_{G1-26: H 2 NHN (O =} ) CCH 2 SCH 2 CH 2 SCH 2 C (= O) NHNH 2
_{G1-27: H 3 C (O =} ) NHCH 2 CH 2 SCH 2 CH 2 SCH 2 CH 2 NHC (= O) CH 3
_{G1-28: H 2 NO 2 SCH 2} CH 2 SCH 2 CH 2 SCH 2 CH 2 SO 2 NH 2
_{G1-29: NaO 3 SCH 2 CH 2} CH 2 SCH 2 CH 2 SCH 2 CH 2 CH 2 SO 3 Na
G1-30: H ₃ CSO ₂ NHCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ NHO ₂ SCH ₃
G1-31: H ₂ N (NH) CSCH ₂ CH ₂ SC (NH) NH ₂ .2HBr
_{G1-32: H 2 (NH) CSCH} 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 SC (NH) NH 2 · 2HCl
G1-33: H ₂ N (NH) CNHCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ NHC (NH) NH ₂ .2HBr
G1-34: [(CH ₃ ) ₃ NCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH ₂ N (CH ₃ ) ₃ ] 2 ⁺ · 2Cl ⁻

  Among the above-exemplified compounds, G1-2 is particularly preferable from the viewpoint that the object and effects of the present invention can be exhibited.

  Next, the compound represented by formula (G2) according to the present invention will be described.

In the formula, M represents a hydrogen atom, a metal atom or quaternary ammonium. Z represents an atomic group necessary for constituting a nitrogen-containing heterocyclic ring. n represents an integer of 0 to 5, Rg ₂₁ represents a substituent, and when n is 2 or more, each Rg ₂₁ may be the same or different, and are connected to each other to form a condensed ring. May be.

Examples of the metal atom represented by M in the general formula (G2) include Li, Na, K, Mg, Ca, Zn, and Ag. Examples of the quaternary ammonium include NH ₄ , N (CH ₃ ) ₄ , N (C ₄ H ₉ ) ₄ , N (CH ₃ ) ₃ C ₁₂ H ₂₅ , N (CH ₃ ) ₃ C ₁₆ H ₃₃ , N (CH ₃ ) ₃ CH ₂ C ₆ H _{5 and the} like It is done.

  Examples of the nitrogen-containing heterocycle having Z as a constituent in the general formula (G2) include, for example, a tetrazole ring, a triazole ring, an imidazole ring, an oxadiazole ring, a thiadiazole ring, an indole ring, an oxazole ring, a benzoxazole ring, and a benzimidazole. Ring, benzothiazole ring, benzoselenazole ring, naphthoxazole ring and the like.

The substituents represented by Rg ₂₁ of the general formula (G2), is not particularly limited, include, for example, substituents as described below.

  Hydrogen atom, halogen atom (eg, fluorine atom, chlorine atom, bromine atom, iodine atom), alkyl group (eg, methyl, ethyl, propyl, i-propyl, butyl, t-butyl, pentyl, cyclopentyl, hexyl, cyclohexyl) Octyl, dodecyl, hydroxyethyl, methoxyethyl, trifluoromethyl, benzyl, etc.), aryl groups (eg, phenyl, naphthyl, etc.), alkylcarbonamide groups (eg, acetylamino, propionylamino, butyroylamino, etc.), aryl Carboxamide groups (eg, benzoylamino), alkylsulfonamide groups (eg, methanesulfonylamino group, ethanesulfonylamino group, etc.), arylsulfonamide groups (eg, benzenesulfonylamino group, toluenesulfonylamino) Group), alkoxy group, aryloxy group (for example, phenoxy), alkylthio group (for example, methylthio, ethylthio, butylthio, etc.), arylthio group (for example, phenylthio group, tolylthio group, etc.), alkylcarbamoyl group (for example, methylcarbamoyl group) Dimethylcarbamoyl, ethylcarbamoyl, diethylcarbamoyl, dibutylcarbamoyl, piperidylcarbamoyl, morpholylcarbamoyl, etc.), arylcarbamoyl groups (eg, phenylcarbamoyl, methylphenylcarbamoyl, ethylphenylcarbamoyl, benzylphenylcarbamoyl, etc.), carbamoyl groups, alkylsulfurates Famoyl groups (eg methylsulfamoyl, dimethylsulfamoyl, ethylsulfamoyl, diethylsulfamoyl, dibu Sulfamoyl, piperidylsulfamoyl, morpholylsulfamoyl, etc.), arylsulfamoyl groups (eg, phenylsulfamoyl, methylphenylsulfamoyl, ethylphenylsulfamoyl, benzylphenylsulfamoyl, etc.), sulfamoyl groups , Cyano group, alkylsulfonyl group (for example, methanesulfonyl group, ethanesulfonyl group, etc.), arylsulfonyl group (for example, phenylsulfonyl, 4-chlorophenylsulfonyl, p-toluenesulfonyl, etc.), alkoxycarbonyl group (for example, methoxycarbonyl, Ethoxycarbonyl, butoxycarbonyl etc.), aryloxycarbonyl group (eg phenoxycarbonyl etc.), alkylcarbonyl group (eg acetyl, propionyl, butyroyl etc.), a A reelcarbonyl group (for example, benzoyl group, alkylbenzoyl group, etc.), an acyloxy group (for example, acetyloxy, propionyloxy, butyroyloxy, etc.), a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group, or a heterocyclic group (for example, , Oxazole ring, thiazole ring, triazole ring, selenazole ring, tetrazole ring, oxadiazole ring, thiadiazole ring, thiazine ring, triazine ring, benzoxazole ring, benzthiazole ring, indolenine ring, benzselenazole ring, naphthothiazole ring , Triazaindolizine ring, diazaindolizine ring, tetraazaindolizine ring group, etc.). These substituents further include those having a substituent.

  Next, although the preferable specific example of a compound represented by general formula (G2) is shown, this invention is not limited to these compounds.

  Among the above-exemplified compounds, G2-12, G2-18, and G2-20 are particularly preferable from the viewpoint that the object and effects of the present invention can be exhibited.

[Thickener added with electrolyte]
In the display element of the present invention, a thickener can be used for the electrolyte. For example, gelatin, gum arabic, poly (vinyl alcohol), hydroxyethyl cellulose, hydroxypropyl cellulose, cellulose acetate, cellulose acetate butyrate, poly ( Vinylpyrrolidone), poly (alkylene glycol), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene-maleic anhydride), copoly ( Styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (eg, poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethanes), phenoxy resins, poly (PVC Redene), poly (epoxides), poly (carbonates), poly (vinyl acetate), cellulose esters, poly (amides), hydrophobic transparent binders such as polyvinyl butyral, cellulose acetate, cellulose acetate butyrate, polyester, Examples include polycarbonate, polyacrylic acid, polyurethane and the like.

  These thickeners may be used in combination of two or more. Further, compounds described on pages 71 to 75 of JP-A No. 64-13546 can be exemplified. Among these, the compounds preferably used are polyvinyl alcohols, polyvinyl pyrrolidones, hydroxypropyl celluloses, and polyalkylene glycols from the viewpoint of compatibility with various additives and improvement in dispersion stability of white particles.

[Electrochromic compound]
<< Electrochromic compound (hereinafter referred to as EC compound or EC dye) >>
The electrochromic compound is not particularly limited as long as it exhibits an action of color development or decoloration by at least one of an electrochemical oxidation reaction and a reduction reaction, and can be appropriately selected according to the purpose.

  Examples of the conductive polymer compound exhibiting EC characteristics include polypyrrole, polythiophene, polyisothianaphthene, polyaniline, polyphenylenediamine, polybenzidine, polyaminophenol, polyvinylcarbazole, polycarbazole, and derivatives thereof.

  In addition, a polymer material composed of a bisterpyridine derivative and a metal ion as described in, for example, JP-A-2007-112957 also exhibits EC characteristics.

  Organic dyes exhibiting EC characteristics include pyridinium compounds such as viologen, azine dyes such as phenothiazine, styryl dyes, anthraquinone dyes, pyrazoline dyes, fluorane dyes, donor / acceptor type compounds (for example, tetracyanoquinodis Methane, tetrathiafulvalene) and the like. In addition, compounds known as redox indicators and pH indicators can also be used.

  In the present invention, the electrochromic compound is preferably fixed to the display side electrode via a silanol bond. For this purpose, the electrochromic compound preferably has a substituent represented by the following formula (A).

Formula _{(A) -Si (Y) n} R '(3-n)
In the formula, Y represents a halogen atom or OR, and R represents an alkyl group or an aryl group. R ′ represents an alkyl group, an alkenyl group, an aryl group or a heterocyclic group, and n represents an integer of 1 to 3. The functional silane represented by the formula (A) (hydrolyzable group such as alkoxysilane or halosilane) may be any as long as it can form a silanol bond, but a trialkoxysilane compound or a trichlorosilane compound can be easily synthesized. It is preferable. Trichlorosilane is highly reactive and can be adsorbed to various metal oxides in a short time, and trialkoxysilane has a relatively mild reactivity, so that the progress of the reaction can be easily controlled. In addition, when a monochlorosilane compound or a monoalkoxysilane compound is used, oligomerization can be prevented, so that the amount of adsorption to the display side electrode can be easily controlled.

EC compounds are classified into the following three classes when classified in terms of color change.
Class 1: EC compounds that change from one specific color to another by redox.
Class 2: EC compounds that are substantially colorless in the oxidized state and exhibit a specific colored state that is the reduced state.
Class 3: EC compounds that are substantially colorless in the reduced state and exhibit a particular colored state that is the oxidized state.

  In the display element of the present invention, the class 1 to class 3 EC compounds can be appropriately selected depending on the purpose and application.

[Class 1 EC compounds]
Class 1 EC compounds are EC compounds that change from a specific color to another color by oxidation-reduction, and are compounds capable of displaying two or more colors in their possible oxidation states.

  Many of the organometallic complexes are classified as Class 1, and ruthenium (II) bipyridine complexes, such as tris (5,5'-dicarboxylethyl-2,2'-bipyridine) ruthenium complexes, are between +2 and -4 valences. From orange to purple, blue, green blue, brown, red rust and red. Many of the rare earth diphthalocyanines also exhibit such multicolor characteristics. For example, in the case of lutetium diphthalocyanine, the color gradually changes from purple to blue, green, and red-orange according to oxidation.

  Many of the conductive polymers are also classified as class 1. For example, polythiophene changes from blue to red by changing from an oxidized state to a reduced state, and polypyrrole changes from brown to yellow. In addition, polyaniline or the like exhibits multi-color characteristics and changes from an amber color of an oxidation state to blue, green, and light yellow in order.

  EC compounds classified as class 1 have a merit that multicolor display is possible with a single compound, but on the other hand, they have a drawback that a state that can be said to be substantially colorless cannot be made.

[Class 2 EC compounds]
Class 2 EC compounds are compounds that are colorless or extremely light in an oxidized state and exhibit a specific colored state that is a reduced state.

  As an organometallic complex classified into class 2, for example, a tris (vasophenanthroline) iron (II) complex can be mentioned, which shows red in a reduced state.

  Examples of organic dyes classified as class 2 include compounds described in JP-A Nos. 62-71934 and 2006-71765, such as dimethyl terephthalate (red) and diethyl 4,4′-biphenylcarboxylate. (Yellow), 1,4-diacetylbenzene (cyan), or tetrazolium salt compounds described in JP-A-1-230026, JP-T-2000-504964, and the like.

  The most representative dyes classified in class 2 are pyridinium compounds such as viologen. Viologen compounds have the advantages of clear display and the ability to have color variations by changing substituents, etc., so they are the most actively studied among organic dyes. ing. Color development is based on organic radicals generated by reduction.

  Examples of pyridinium-based compounds such as viologen include compounds described in the following patents, starting with JP 2000-506629 A.

  JP-A-5-70455, JP-A-5-170738, JP-A-2000-235198, JP-A-2001-114769, JP-A-2001-172293, JP-A-2001-181293, JP-A-2001-181293, JP-T-2001-510590. JP-A-2004-101729, JP-A-2006-154683, JP-T-2006-519222, JP-A-2007-31708, JP-A-2007-171781, JP-A-2007-219271, JP-A-2007-219272, and JP-A-2007-279659. No. 2007-279570, No. 2007-279571, No. 2007-279572, etc.

  Examples of pyridinium compounds such as viologen that can be used in the present invention are shown below, but are not limited thereto.

[Class 3 EC compounds]
Class 3 EC compounds are compounds that are colorless or very pale in the reduced state and exhibit a specific colored state that is an oxidized state.

  Examples of the conductive polymer classified as class 3 include few examples, but examples thereof include phenyl ether compounds described in JP-A-6-263846.

  Many dyes are known as class 3 dyes, styryl dyes, azine dyes such as phenazine, phenothiazine, phenoxazine, and acridine, azole dyes such as imidazole, oxazole, and thiazole are preferable. .

  Examples of styryl dyes, azine dyes, and azole dyes that can be used in the present invention are shown below, but are not limited thereto.

  In a preferred embodiment of the present invention, a metal salt that reversibly dissolves and precipitates by an electrochemical redox reaction is used in combination with the EC dye, and a multicolor of three or more colors of black display, white display, and non-black color display. Display. In this case, since the metal salt is reduced to give a black display, the EC dye is preferably a class 3 EC compound that develops color by oxidation, and is particularly an azole series in terms of color development diversity, low driving voltage, memory properties, and the like. A dye is preferred. In the present invention, the most preferred dye is a compound represented by the general formula (L).

  Hereinafter, the electrochromic compound represented by the general formula (L) according to the present invention will be described.

In the general formula (L), Rl ₁ represents a substituted or unsubstituted aryl group, and Rl ₂ and Rl ₃ each represent a hydrogen atom or a substituent. X represents> N—Rl ₄ , an oxygen atom or a sulfur atom, and Rl ₄ represents a hydrogen atom or a substituent.

When Rl ₁ represents an aryl group having a substituent, the substituent is not particularly limited, and examples thereof include the following substituents.

  Alkyl groups (eg, methyl, ethyl, propyl, isopropyl, tert-butyl, pentyl, hexyl, etc.), cycloalkyl groups (eg, cyclohexyl, cyclopentyl, etc.), alkenyl groups, cycloalkenyl groups , Alkynyl groups (for example, propargyl group), glycidyl groups, acrylate groups, methacrylate groups, aromatic groups (for example, phenyl group, naphthyl group, anthracenyl group, etc.), heterocyclic groups (for example, pyridyl group, thiazolyl group, oxazolyl group) Group, imidazolyl group, furyl group, pyrrolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, triphoranyl group, piperidinyl group, pyrazolyl group, tetrazolyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy) Group, pliers Oxy group, cyclopentyloxy group, hexyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, etc.) , Aryloxycarbonyl group (for example, phenyloxycarbonyl group), sulfonamide group (for example, methanesulfonamide group, ethanesulfonamide group, butanesulfonamide group, hexanesulfonamide group, cyclohexanesulfonamide group, benzenesulfonamide group ), Sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylamino) Sulfonyl group, phenylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), urethane group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, phenylureido group, 2-pyridylureido group, etc.), acyl Groups (eg, acetyl, propionyl, butanoyl, hexanoyl, cyclohexanoyl, benzoyl, pyridinoyl, etc.), carbamoyl groups (eg, aminocarbonyl, methylaminocarbonyl, dimethylaminocarbonyl, propylamino) Carbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), acylamino group (for example, acetylamino group, benzoyla) Mino group, methylureido group, etc.), sulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, phenylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, amino group, Ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, anilino group, 2-pyridylamino group, etc.), halogen atom (eg chlorine atom, bromine atom, iodine atom etc.), cyano group, nitro group, sulfo group Carboxyl group, hydroxyl group, phosphono group (for example, phosphonoethyl group, phosphonopropyl group, phosphonooxyethyl group) and the like. Further, these groups may be further substituted with these groups.

Rl ₁ is preferably a substituted or unsubstituted phenyl group, and more preferably a substituted or unsubstituted 2-hydroxyphenyl group or 4-hydroxyphenyl group.

Rl 2 is not particularly limited _as, substituent represented by Rl _3, such substituents exemplified as a substituent on the aryl group of the Rl ₁ can be mentioned. Preferably, Rl ₂ and Rl ₃ are an alkyl group, a cycloalkyl group, an aromatic group, or a heterocyclic group, which may have a substituent. Rl ₂ and Rl ₃ may be linked to each other to form a ring structure. As a combination of Rl ₂ and Rl ₃ , both of them may be a phenyl group or a heterocyclic group which may have a substituent, or one of them may be a phenyl group or a heterocyclic group which may have a substituent. Yes, the other is a combination of alkyl groups which may have a substituent.

X is preferably a> N-Rl _4. Rl ₄ is preferably a hydrogen atom, an alkyl group, an aromatic group, a heterocyclic group or an acyl group, more preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 5 to 10 carbon atoms, or acyl. It is a group.

In the display element of the present invention, it is preferable that the compound represented by the general formula (L) according to the present invention has a group that chemically or physically adsorbs on the electrode surface. The chemical adsorption according to the present invention is a relatively strong adsorption state due to a chemical bond with the electrode surface, and the physical adsorption according to the present invention is a relatively strong van der Waals force acting between the electrode surface and the adsorbed substance. It is weakly adsorbed. The adsorptive group according to the present invention is preferably a chemisorbable group. Examples of the adsorptive group to be chemisorbed include —COOH, —P═O (OH) ₂ , —OP═O (OH) ₂ and -Si (OR) ₃ (R represents an alkyl group) is preferable.

  Among the azole dyes represented by the general formula (L), an imidazole dye represented by the following general formula (L2) is particularly preferable.

Wherein, Rl _21, Rl ₂₂ represents an aliphatic group, an aliphatic oxy group, an acylamino group, a carbamoyl group, an acyl group, a sulfonamido group, a sulfamoyl group, R1 ₂₃ represents an aromatic group or an aromatic heterocyclic group Rl ₂₄ represents a hydrogen atom, an aliphatic group, an aromatic group or an aromatic heterocyclic group, and Rl ₂₅ represents a hydrogen atom, an aliphatic group, an aromatic group or an acyl group.

These groups represented by Rl _{21 to} Rl ₂₅ may be further substituted with an arbitrary substituent. However, at least one of the groups represented by Rl _{21 to} Rl ₂₅ has —COOH, —P═O (OH) ₂ , —OP═O (OH) ₂ or —Si (OR) ₃ (R Represents an alkyl group).

The group represented by the general formulas Rl ₂₁ and Rl ₂₂ is preferably an alkyl group (particularly a branched alkyl group), a cycloalkyl group, an alkyloxy group, or a cycloalkyloxy group. Rl ₂₃ is preferably a substituted or unsubstituted phenyl group, a 5-membered or 6-membered heterocyclic group (for example, thienyl group, furyl group, pyrrolyl group, pyridyl group, etc.). Rl ₂₄ is preferably a substituted or unsubstituted phenyl group, a 5-membered or 6-membered heterocyclic group or an alkyl group. Rl ₂₅ is particularly preferably a hydrogen atom or an aryl group.

Further, when fixing the general formula (L2) on the electrode, at least one of the groups represented by Rl _{21 to} Rl ₂₅ has a partial structure of —P═O (OH) ₂ , —Si (OR) _3. (R represents an alkyl group) is preferable, and it is particularly preferable to have —Si (OR) ₃ (R represents an alkyl group) as a partial structure of the group represented by Rl ₂₃ or Rl ₂₄ .

  Specific examples of the EC dye represented by the general formula (L2) and specific examples of the EC dye contained in the general formula (L) that do not correspond to the general formula (L2) are shown below. The invention is not limited to these exemplified compounds.

[Method of fixing electrochromic compound to electrode]
The electrochromic compound is fixed to the display side electrode on the display side electrode surface. In order to increase the color density, it is desirable to fix the electrochromic compound on the display-side electrode surface at a high density. However, it is preferable that the portion of the display-side electrode surface where the electrochromic compound is immobilized occupies most of the surface because the reaction site on the display electrode of the promoter, metal, or metal salt becomes small and the reaction is suppressed. Absent. Therefore, it is preferable to fix the electrochromic compound so that a portion where the electrochromic compound is not fixed to the display-side electrode surface can be secured in an appropriate region.

  In a laminated display-side electrode composed of a transparent conductive layer and a porous layer, the transparent conductive layer has higher conductivity than the porous layer, so that the electrochemical reaction of the promoter and metal or metal ions occurs in the transparent conductive layer. Then, since the rewriting speed is expected to be faster, it is preferable that the fixing density of the electrochromic compound is lower on the transparent conductive layer side than on the porous layer side.

As a method for manufacturing such an electrode, for example, the following methods are available.
(1) A porous electrode is prepared as a display side electrode.
(2) A coating layer is formed on the display side electrode. The covering layer is formed so as not to be formed on at least a part of the display side electrode. As a method for forming such a coating layer, an electrolyte containing a metal salt compound is disposed between a porous electrode and another electrode (preferably an electrode made of the same metal as the metal salt compound), There is a method of forming a coating layer by applying a voltage to deposit a metal on the display-side electrode. Moreover, you may form the coating layer which consists of an organic compound similarly by voltage application using the electrolyte containing the organic compound which melt | dissolves and / or deposits electrochemically, such as a viologen, instead of a metal salt compound. In order to form the coating layer so as not to be formed on at least a part of the display-side electrode, the voltage and application time are adjusted (for example, a constant voltage of 1.5 V for 5 seconds). Adjust the amount. When applied to the display-side electrode of an ED + EC display element, the covering layer is preferably formed of the same type of metal as the metal or metal salt used in the display element. Further, the amount of metal to be deposited is preferably set to the same level as when the metal is deposited by the display element to display black.

When a porous layer made of highly conductive particles is used, the metal or the organic compound is mainly deposited on the porous layer. On the other hand, when a porous layer made of particles having low conductivity is used, the metal or the organic compound is mainly deposited on the transparent conductive layer, and the fixed density of the electrochromic compound is higher than that of the porous layer. This is preferred for lowering on the side.
(3) An electrochromic compound is fixed to the display side electrode. A general method can be used as the fixing method, and the electrochromic compound solution may be brought into contact with the display-side electrode. In order to firmly fix the electrochromic compound to the display-side electrode, it is preferably fixed to the display-side electrode through a silanol bond, and the electrochromic compound having a substituent represented by the above formula (A) Is preferably used. Further, after treatment with a functional group-attached silane coupling agent, an electrochromic compound having a substituent that generates a chemical bond with the functional group may be reacted.
(4) The coating layer on the display side electrode is dissolved. Dissolution may be electrochemical or chemical. As an example of the former, a method such as disposing an electrolyte between the display-side electrode and another electrode and applying a voltage to dissolve a metal or organic compound that is a coating layer on the display-side electrode is an example of the latter. Examples of the method include soaking in an acid.

  FIG. 1 shows a schematic diagram of a method for fixing an electrochromic compound to an electrode.

  FIG. 2 shows another schematic diagram of a method for fixing an electrochromic compound to an electrode.

  As described above, the coating layer is a layer that plays a role of masking the conductive layer of the display-side electrode formed by laminating the conductive layer and the porous layer so that the electrochromic compound is not fixed to the conductive layer. is there.

  According to the above method, since the electrochromic compound is fixed in a state where a part of the display-side electrode is covered, after the coating layer is dissolved and removed, the display in which the electrochromic compound is not fixed at least partially Side electrodes can be manufactured.

〔promoter〕
In the display element of the present invention, an auxiliary compound (promoter) that can be oxidized and reduced may be added in addition to the EC compound in order to promote the electrochemical reaction of the electrochromic material. The promoter may be one that does not change the optical density in the visible region (400 to 700 nm) as a result of the oxidation-reduction reaction, or one that changes, that is, the EC compound, or may be immobilized on the electrode. It may well be added to the electrolyte. These promoters can be used, for example, as counter electrode reactants or as redox mediators.

  For example, when an EC compound is oxidized (or reduced) in color on the display electrode side, a high color density can be obtained with a low driving voltage by utilizing a reduction (or oxidation) reaction of a promoter on the counter electrode side. . Thus, when using a promoter as a counter electrode reactive substance, it is preferable to fix an EC compound on a display electrode, and to fix and use a promoter having redox activity opposite to that of the EC compound on a counter electrode. When a promoter is used as a counter electrode material, it is preferable that the promoter does not change the optical density in the visible region (400 to 700 nm) as a result of the redox reaction. However, as described in the preferred embodiment of the present invention, in the embodiment in which white scatterers are used in the display element to block color development by the promoter, the promoter in which the optical density in the visible region (400 to 700 nm) changes. That is, an EC compound may be used. Such a configuration is preferable because it facilitates selection of a promoter. As another embodiment, it is one of preferred embodiments to use a promoter that exhibits the same color as the EC compound on the display electrode side.

  On the other hand, the redox mediator is a material generally used in the field of organic electrolytic synthesis. Each organic compound has an oxidation overvoltage that depends on the electrolysis method and electrolysis conditions, in addition to its own oxidation potential, and when the anode potential is higher than the combined oxidation potential, an oxidation reaction actually occurs. Due to experimental limitations on the anodic potential, it is not possible to oxidize all substrates by direct methods. When a substrate having a high oxidation potential is oxidized, no electron transfer from the substrate to the anode occurs. When a mediator that causes electron transfer (oxidation) to the anode at a low potential coexists in this reaction system, the mediator is first oxidized, and the substrate is oxidized by the oxidized mediator to obtain a product. The advantage of this reaction system is that the substrate can be oxidized at an anode potential lower than the oxidation potential of the substrate, and the oxidized mediator returns to the original mediator when the substrate is oxidized. Is to act as a catalytic amount. Further, since oxidation at a low potential is possible, decomposition of the substrate and product can be suppressed.

  In the present invention, for example, when an EC compound that oxidizes and colors is used as the substrate, a display element can be driven with a low driving voltage by coexisting a catalytic amount of an oxidation mediator, and the durability of the display element is enhanced. Further, there are advantages such as an improvement in display switching speed and high color development efficiency. Similarly, the above effect can be obtained by a combination of a reducing mediator and an EC compound that produces a reducing color.

  In the display element of the present invention, as shown in the field of organic electrolytic synthesis, a single mediator may be used, or a plurality of mediators may be used in combination. When a promoter is used as a mediator in the present invention, it is preferable to use an EC compound immobilized on a display electrode and a promoter localized in the vicinity thereof.

  In the present invention, a promoter may be used as a counter electrode reactant or a mediator. For both purposes, a plurality of promoters may be used in combination at the same time.

  There is no restriction | limiting in particular as a promoter, According to the objective, it can select suitably. In particular, when used as a counter electrode reactant, a known EC compound can be used. In addition, when used as a redox mediator, according to the properties of EC compounds used as display dyes, Journal of Synthetic Organic Chemistry, Vol. 43, No. 6 (Special Issue on Organic Synthesis Using Electric Energy) (1985) etc. The known mediators described can be appropriately selected and used.

Examples of preferred promoters that can be used in the present invention include the following compounds.
1) N-oxyl derivatives typified by TEMPO, N-hydroxyphthalimide derivatives, hydroxamic acid derivatives, etc., compounds having an N—O bond 2) Allyloxy free radicals introduced with a bulky substituent at the 0-position, such as galvinoxyl 3) Ferrocene etc., metallocene derivatives 4) benzyl (diphenylethanedione) derivatives 5) tetrazolium salts / formazan derivatives 6) azine compounds such as phenazine, phenothiazine, phenoxazine, acridine 7) pyridinium compounds such as viologen and others, benzoquinone Derivatives, hydrazyl free radical compounds such as verdazil, thiazyl free radical compounds, hydrazone derivatives, phenylenediamine derivatives, triallylamine derivatives, tetrathiafulvalene derivatives, tetracyanoquinodimethane derivatives, thianthrene derivatives A conductor or the like can also be used as a promoter.

  In the display element of the present invention, promoters in the categories 1) to 7) are preferable, and 1) is particularly preferable.

  Hereinafter, compounds in the category 1) will be described in detail.

  N-oxyl (also called nitroxide radical) is an oxygen-centered radical generated by radically cleaving the oxygen-hydrogen bond of hydroxylamine. Nitroxide radicals are known to have two reversible redox pairs as shown in the scheme below. The nitroxide radical becomes an oxoammonium cation by one-electron oxidation, which is reduced to regenerate the radical. The nitroxide radical is converted into an aminoxy anion by one-electron reduction, which is oxidized to regenerate the radical. Therefore, the nitroxide radical can function as a p-type counter electrode reactant or an n-type counter electrode reactant. In addition, the oxoammonium cation has a high oxidation ability and can function as a mediator because it can oxidize a leuco dye or the like.

  The N-oxyl derivative may be contained in the electrolyte or may be immobilized on the electrode surface. Examples of the method of immobilizing on the electrode surface include a method of introducing a group that chemically or physically adsorbs with the electrode surface into the N-oxyl derivative, a method of polymerizing the N-oxyl derivative to form a thin film on the electrode surface, and the like. It is done. The N-oxyl derivative may be added in the form of an N-oxyl radical, or may be added in the form of an N-hydroxy compound, and further in the form of an oxoammonium cation.

  As N-oxyl derivatives, derivatives substituted with various substituents such as TEMPO (2,2,6,6-tetramethylpiperidinyl-N-oxyl) are commercially available. In addition, various derivatives including polymers can be easily synthesized according to known literature.

  In general, it is known that when hydrogen is substituted on the α-position carbon of the nitroxide radical, it is easily disproportionated to hydroxyamine and nitrone. For this reason, the four methyl groups at the N-oxyl group α-position of TEMPO can be said to be indispensable structures for existing as stable radicals, but conversely, the reactivity may decrease due to steric hindrance of these four methyl groups. is there. Azaadamantane N-oxyl derivatives or azabicyclo N-oxyl derivatives are preferred in that they do not cause a decrease in activity.

  Next, N-hydroxyphthalimide derivatives, hydroxamic acid derivatives and the like will be described. As shown in the following scheme, phthalimide N-oxyl (PINO) generated by electrode oxidation of N-hydroxyphthalimide (NHPI) oxidizes a secondary alcohol to produce a ketone. That is, it has been reported that NHPI functions as an oxidation mediator (Chem. Commun., 1983, 479). As can be seen from this example, it is understood that the redox couple of NHPI / PINO functions as a counter electrode reactant or mediator also in the display element of the present invention. As with NHPI, hydroxamic acid derivatives and trihydroxyimino cyanuric acid (THICA) can also be used as promoters.

  When the display element of the present invention is manufactured using these compounds, it is preferably added in the state of N—OH. After a display element is manufactured in the state of N—OH, radicals are generated by driving the display element to oxidize.

  The promoter represented by the category of 1) can be represented by the following general formula (M1), and promoters represented by the following general formulas (M2) to (M5) are preferable. In particular, a polycyclic N-oxyl derivative represented by the general formula (M6) is preferable.

  Various promoters represented by the general formulas (M1) to (M5) are commercially available and can be easily obtained. Various derivatives can be easily synthesized according to known literature. The promoter represented by the general formula (M6) is J.P. Am. Chem. Soc. 128, 8412 (2006) and Tetrahedron Letters, 49, (2008), 48-52.

  Further, promoters obtained by polymerizing these are, for example, JP-A Nos. 2004-227946, 2004-228008, 2006-73240, 2007-35375, 2007-70384, and 2007-184227. No. 2007, No. 2007-298713 and the like can be synthesized.

In the formula, Rm ₁₁ and Rm ₁₂ are each independently an optionally substituted aliphatic hydrocarbon group, aromatic hydrocarbon group, heterocyclic group or>C═O,>C═S,> C═N. A group bonded to a nitrogen atom via —Rm ₁₃ ; Rm ₁₃ represents a hydrogen atom, an aliphatic hydrocarbon group which may have a substituent, an aromatic hydrocarbon group or a heterocyclic group. Rm ₁₁ and Rm ₁₂ may be connected to each other to form a cyclic structure.

  The aliphatic hydrocarbon group includes chain and cyclic groups, and the chain group includes linear and branched groups. Such aliphatic hydrocarbon groups include methyl, ethyl, vinyl, propyl, isopropyl, propenyl, butyl, iso-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, iso-hexyl, cyclohexyl, cyclohexenyl, Examples include octyl, iso-octyl, cyclooctyl, 2,3-dimethyl-2-butyl and the like.

  Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group. Examples of the heterocyclic group include a pyridyl group, a thiazolyl group, an oxazolyl group, an imidazolyl group, a furyl group, a pyrrolyl group, a pyrazinyl group, a pyrimidinyl group, and a pyridazinyl group. , Serenazolyl group, sulfolanyl group, piperidinyl group, pyrazolyl group, tetrazolyl group, morpholino group and the like.

  These substituents may further have a substituent. These substituents are not particularly limited, and examples thereof include alkyl groups (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, Tetradecyl group, pentadecyl group etc.), cycloalkyl group (eg cyclopropyl group, cyclopentyl group, cyclohexyl group etc.), alkenyl group (eg vinyl group, allyl group, butenyl group, octenyl group etc.), cycloalkenyl group (eg , 2-cyclopenten-1-yl group, 2-cyclohexen-1-yl group, etc.), alkynyl group (eg, propargyl group, ethynyl group, trimethylsilylethynyl group, etc.), aryl group (eg, phenyl group, naphthyl group, p) -Tolyl group, m-chlorophenyl group, o-hexadecanoylamino Phenyl group, etc.), heterocyclic group (for example, pyridyl group, thiazolyl group, oxazolyl group, imidazolyl group, furyl group, pyrrolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, sulfolanyl group, piperidinyl group, pyrazolyl group, Tetrazolyl group, morpholino group, etc.), heterocyclic oxy group (for example, 1-phenyltetrazol-5-oxy group, 2-tetrahydropyranyloxy group, pyridyloxy group, thiazolyloxy group, oxazolyloxy group, imidazolyloxy group, etc.) ), Halogen atoms (for example, chlorine atom, bromine atom, iodine atom, fluorine atom, etc.), alkoxy groups (for example, methoxy group, ethoxy group, propyloxy group, tert-butoxy group, pentyloxy group, hexyloxy group, octyl) Oxy group, dodecyloxy Group), cycloalkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (for example, phenoxy group, 2-naphthyloxy group, 2-methylphenoxy group, 4-tert-butylphenoxy group, 3 -Nitrophenoxy group, 2-tetradecanoylaminophenoxy group, etc.), alkylthio group (for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (for example, Cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, 1-naphthylthio group, etc.), heterocyclic thio group (for example, pyridylthio group, thiazolylthio group, oxazolylthio group, imidazolylthio group, furylthio group, pinyl) Rorylthio group, etc.), alkoxycarbonyl group (eg, methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl) Group), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylamino) Sulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, morpholinosulfonyl group, pyrrolidinosulfonyl group, etc.), ureido (For example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), acyl group (for example, acetyl group Ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, Formyloxy, acetyloxy, pivaloyloxy, stearoyloxy, benzoyloxy, p-methoxyphenylcarbonyloxy, ethylcarbonyloxy, Rucarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), acylamino group (for example, acetylamino group, benzoylamino group, formylamino group, pivaloylamino group, lauroylamino group, 3, 4, 5-tri-n-octyloxyphenylcarbonylamino group), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octyl) Aminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group , Morpholinocarbonyl group, piperazinocarbonyl group, etc.), alkanesulfinyl group or arylsulfinyl group (for example, methanesulfinyl group, ethanesulfinyl group, butanesulfinyl group, cyclohexanesulfinyl group, 2-ethylhexanesulfinyl group, dodecanesulfinyl group) , Phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkanesulfonyl group or arylsulfonyl group (for example, methanesulfonyl group, ethanesulfonyl group, butanesulfonyl group, cyclohexanesulfonyl group, 2-ethylhexanesulfonyl group, Dodecanesulfonyl group, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, methylamino group, Tilamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, N-methylanilino group, diphenylamino group, naphthylamino group, 2-pyridylamino group), silyloxy group (Eg, trimethylsilyloxy group, tert-butyldimethylsilyloxy group, etc.), aminocarbonyloxy group (eg, N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyloxy group, morpholinocarbonyloxy group, N, N -Di-n-octylaminocarbonyloxy group, Nn-octylcarbamoyloxy group, etc.), alkoxycarbonyloxy group (for example, methoxycarbonyloxy group, ethoxycarbonyloxy group, tert-butoxycarbonyl) Oxy group, n-octylcarbonyloxy group, etc.), aryloxycarbonyloxy group (for example, phenoxycarbonyloxy group, p-methoxyphenoxycarbonyloxy group, pn-hexadecyloxyphenoxycarbonyloxy group, etc.), alkoxycarbonylamino Groups (for example, methoxycarbonylamino group, ethoxycarbonylamino group, tert-butoxycarbonylamino group, n-octadecyloxycarbonylamino group, N-methyl-methoxycarbonylamino group, etc.), aryloxycarbonylamino groups (for example, phenoxycarbonyl) Amino group, p-chlorophenoxycarbonylamino group, mn-octyloxyphenoxycarbonylamino group, etc.), sulfamoylamino group (for example, sulfamoylamino group, N, N -Dimethylaminosulfonylamino group, Nn-octylaminosulfonylamino group, etc.), mercapto group, arylazo group (eg, phenylazo group, naphthylazo group, p-chlorophenylazo group, etc.), heterocyclic azo group (eg, pyridylazo group) , Thiazolylazo group, oxazolylazo group, imidazolylazo group, furylazo group, pyrrolylazo group, 5-ethylthio-1,3,4-thiadiazol-2-ylazo group, etc., imino group (for example, N-succinimido-1-yl group, N-phthalimido-1-yl group, etc.), phosphino group (for example, dimethylphosphino group, diphenylphosphino group, methylphenoxyphosphino group, etc.), phosphinyl group (for example, phosphinyl group, dioctyloxyphosphinyl group, di) Ethoxyphosphinyl group, etc.), phosphine Nyloxy group (for example, diphenoxyphosphinyloxy group, dioctyloxyphosphinyloxy group, etc.), phosphinylamino group (for example, dimethoxyphosphinylamino group, dimethylaminophosphinylamino group, etc.), silyl group (For example, trimethylsilyl group, tert-butyldimethylsilyl group, phenyldimethylsilyl group, etc.), cyano group, nitro group, hydroxyl group, sulfo group, carboxyl group and the like can be mentioned.

  The compound represented by the general formula (M1) may be a multimer such as a dimer or trimer linked by these substituents, or may be a polymer.

In the formula, Rm _{21 to} Rm ₂₄ each independently represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a heterocyclic group which may have a hydrogen atom or a substituent. These aliphatic hydrocarbon group, aromatic hydrocarbon group, and heterocyclic group have the same meanings as those in formula (M1).

Z ₁ represents an atomic group necessary for forming a cyclic structure, and preferably forms a 5-membered ring or a 6-membered ring. Z ₁ may further have a substituent, and examples of the substituent include the same substituents as those exemplified in the general formula (M1). The atoms constituting Rm _{21 to} Rm ₂₄ and Z ₁ may be linked to each other to form a cyclic structure. For example, together with the nitrogen atom, a polycyclic structure such as an azanorbornene structure or an azaadamantane structure is taken. Also good.

  The ring structure of the compound represented by the general formula (M2) is preferably a piperidine ring, a pyrrolidine ring, or an azaadamantane ring.

In the formula, Rm ₃₁ is an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a heterocyclic ring which may have a substituent, which is substituted directly or through an oxygen atom, a nitrogen atom or a sulfur atom with a carbonyl carbon atom. Rm ₃₂ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a heterocyclic group which may have a substituent. These aliphatic hydrocarbon group, aromatic hydrocarbon group, and heterocyclic group have the same meanings as those in formula (M1).

  In the present invention, it is one of the preferred embodiments that the N-oxyl derivative according to the present invention is a compound represented by the general formula (M3).

Rm ₃₁ and Rm ₃₂ may be connected to each other to form a cyclic structure. In the general formula (M3), Rm ₃₂ is preferably an aromatic hydrocarbon group, and particularly preferably a phenyl group which may have a substituent. The substituent on the phenyl group is preferably an electron-withdrawing group such as a cyano group, an alkoxycarbonyl group, or a trifluoromethyl group. Rm ₃₁ is preferably a phenyl group or an aliphatic hydrocarbon group directly bonded to a carbonyl carbon atom, particularly preferably a branched alkyl group or a cycloalkyl group.

  Note that it is preferable that the compound represented by the general formula (M3) be added in a state of N—OH to manufacture a display element.

In the formula, Z ₂ represents an atomic group necessary for forming a cyclic structure, and may further have a substituent.

  In this invention, it is one of the preferable aspects that the N-oxyl derivative which concerns on this invention is a compound represented by the said general formula (M4).

In the general formula (M4), Z ₂ represents an atomic group necessary for forming a cyclic structure, and preferably forms a 5-membered ring or a 6-membered ring. Z ₂ may further have a substituent, and examples of the substituent include the substituents exemplified in Formula (M1). Z ₂ may be a condensed ring.

  Note that the compound represented by the general formula (M4) is preferably added in the state of N—OH to manufacture a display element.

Wherein, Rm ₅₁ ~Rm ₅₅ are each an aliphatic substituted independently a hydrocarbon group, an aromatic hydrocarbon group, a heterocyclic group. These aliphatic hydrocarbon group, aromatic hydrocarbon group, and heterocyclic group have the same meanings as those in formula (M1).

  In this invention, it is one of the preferable aspects that the N-oxyl derivative which concerns on this invention is a compound represented by the said general formula (M5).

In the general formula (M5), Rm ₅₁ is preferably an aromatic hydrocarbon group, particularly preferably a phenyl group which may have a substituent. The substituent on the phenyl group is preferably an electron-withdrawing group such as a cyano group, an alkoxycarbonyl group, or a trifluoromethyl group. The Rm ₅₁ ~Rm _55, preferably an alkyl group having 1 to 6 carbon atoms, a methyl group is particularly preferred.

In the formula, Rm ₆₁ and Rm ₆₂ each independently represent a hydrogen atom or an aliphatic hydrocarbon group which may have a substituent, and Z _{3 to} Z ₅ each represents an atomic group necessary for forming a cyclic structure. , N represents 0 or 1.

In General Formula (M6), Rm ₆₁ and Rm ₆₂ each independently represent a hydrogen atom or an aliphatic hydrocarbon group that may have a substituent. Rm ₆₁ and Rm ₆₂ are preferably a hydrogen atom or a linear alkyl group having 4 or less carbon atoms, and at least one of Rm ₆₁ and Rm ₆₂ is preferably a hydrogen atom.

Z _{3 to} Z ₅ each represent an atomic group necessary for forming a cyclic structure (for example, carbon, nitrogen, oxygen, sulfur, etc.), and each preferably forms a 5-membered ring or a 6-membered ring. Z _{3 to} Z ₅ may further have a substituent.

  n represents 0 or 1, but when n = 0, the general formula (6) represents a bicyclo compound, and when n = 1, a tricyclo compound.

  As the compound represented by the general formula (M6), n = 1 is preferable, and an azaadamantane derivative is particularly preferable.

  Specific examples of promoters that can be used in the present invention are shown below, but are not limited thereto.

[White scattered matter]
In the present invention, from the viewpoint of further increasing the display contrast and the white display reflectance, it is preferable to contain a white scattering material, and a porous white scattering layer may be formed and present.

  The porous white scattering layer applicable to the present invention can be formed by applying and drying an aqueous mixture of an aqueous polymer and a white pigment that is substantially insoluble in the electrolyte solvent.

  Examples of the white pigment applicable in the present invention include titanium dioxide (anatase type or rutile type), barium sulfate, calcium carbonate, aluminum oxide, zinc oxide, magnesium oxide and zinc hydroxide, magnesium hydroxide, magnesium phosphate, Magnesium hydrogen phosphate, alkaline earth metal salt, talc, kaolin, zeolite, acidic clay, glass, organic compounds such as polyethylene, polystyrene, acrylic resin, ionomer, ethylene-vinyl acetate copolymer resin, benzoguanamine resin, urea-formalin resin, A melamine-formalin resin, a polyamide resin, or the like may be used alone or in combination, or in a state having voids that change the refractive index in the particles.

In the present invention, among the white particles, titanium dioxide, zinc oxide, and zinc hydroxide are preferably used. In addition, titanium dioxide surface-treated with inorganic oxides (Al ₂ O ₃ , AlO (OH), SiO _2, etc.), in addition to these surface treatments, trimethylolethane, triethanolamine acetate, trimethylcyclosilane, etc. Titanium dioxide subjected to organic treatment can be used.

  Of these white particles, it is more preferable to use titanium oxide or zinc oxide from the viewpoint of coloring prevention at high temperature and the reflectance of the element due to the refractive index.

  In the present invention, examples of the water-based polymer that does not substantially dissolve in the electrolyte solvent include a water-soluble polymer and a polymer dispersed in the water-based solvent.

Examples of water-soluble compounds include proteins such as gelatin and gelatin derivatives, cellulose derivatives, natural compounds such as starch, gum arabic, dextran, pullulan and carrageenan, and other natural compounds, polyvinyl alcohol, polyvinyl pyrrolidone, acrylamide polymers and their Examples include synthetic polymer compounds such as derivatives. Examples of gelatin derivatives include acetylated gelatin, phthalated gelatin, polyvinyl alcohol derivatives include terminal alkyl group-modified polyvinyl alcohol, terminal mercapto group-modified polyvinyl alcohol, and cellulose derivatives include hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, and the like. It is done. Further, Research Disclosure and those described on pages (71) to (75) of JP-A No. 64-13546, US Pat. No. 4,960,681, JP-A No. 62-245260, etc. superabsorbent polymers described, namely -COOM or -SO 3 M _(M is a hydrogen atom or an alkali metal) homopolymer or a vinyl monomer together or with other vinyl monomers of the vinyl monomer having a (e.g., sodium methacrylate, Copolymers with ammonium acid, potassium acrylate, etc.) are also used. Two or more of these binders can be used in combination.

  In the present invention, gelatin and gelatin derivatives, or polyvinyl alcohol or derivatives thereof can be preferably used.

  Polymers dispersed in an aqueous solvent include natural rubber latex, styrene butadiene rubber, butadiene rubber, nitrile rubber, chloroprene rubber, isoprene rubber and other latexes, polyisocyanate, epoxy, acrylic, silicone, polyurethane, Examples thereof include a thermosetting resin in which urea, phenol, formaldehyde, epoxy-polyamide, melamine, alkyd resin, vinyl resin and the like are dispersed in an aqueous solvent. Of these polymers, it is preferable to use an aqueous polyurethane resin described in JP-A-10-76621.

  In the present invention, “not substantially soluble in the electrolyte solvent” is defined as a state where the dissolved amount is 0 to 10 g per kg of the electrolyte solvent at −20 to 120 ° C., and is based on mass measurement method, liquid chromatogram or gas chromatogram. The amount of dissolution can be determined by a known method such as a component quantification method.

  In the present invention, the water mixture of the water-based compound and the white pigment is preferably in a form in which the white pigment is dispersed in water according to a known dispersion method. The mixing ratio of the aqueous compound / white pigment is preferably 1 to 0.01, more preferably 0.3 to 0.05 in terms of volume ratio.

  In the present invention, the medium for applying the water mixture of the water-based compound and the white pigment may be at any position as long as it is on the component between the counter electrodes of the display element, but on the electrode surface of at least one of the counter electrodes. It is preferable to give to. As a method for applying to a medium, for example, a coating method, a liquid spraying method, a spraying method via a gas phase, a method of flying droplets using vibration of a piezoelectric element, for example, a piezoelectric inkjet head, Examples thereof include a bubble jet (registered trademark) type ink jet head that causes droplets to fly using a thermal head that uses bumping, and a spray type that sprays liquid by air pressure or liquid pressure.

  The coating method can be appropriately selected from known coating methods. For example, an air doctor coater, blade coater, rod coater, knife coater, squeeze coater, impregnation coater, reverse roller coater, transfer roller coater, curtain coater, double coater Examples include roller coaters, slide hopper coaters, gravure coaters, kiss roll coaters, bead coaters, cast coaters, spray coaters, calendar coaters, and extrusion coaters.

  Drying of the water mixture of the aqueous compound and the white pigment applied on the medium may be performed by any method as long as water can be evaporated. For example, heating from a heat source, a heating method using infrared light, a heating method using electromagnetic induction, and the like can be given. Further, water evaporation may be performed under reduced pressure.

  Porous as used in the present invention refers to the formation of a porous white scattering material by applying a water admixture of the water-based compound and the white pigment onto the electrode and drying it, and then the silver or silver is chemically treated on the scattering material. After supplying an electrolyte solution containing the compound contained in the structure, it can be sandwiched between opposing electrodes, giving a potential difference between the opposing electrodes, causing a silver dissolution precipitation reaction, and penetrating ions that can move between the electrodes Tell the state.

  In the display element of the present invention, it is desirable to carry out a curing reaction of the water-based compound with a curing agent during or after applying and drying the water mixture described above.

  Examples of the hardener used in the present invention include, for example, U.S. Pat. No. 4,678,739, column 41, 4,791,042, JP-A-59-116655, and 62-245261. No. 61-18942, 61-249054, 61-245153, JP-A-4-218044, and the like. More specifically, aldehyde hardeners (formaldehyde, etc.), aziridine hardeners, epoxy hardeners, vinyl sulfone hardeners (N, N'-ethylene-bis (vinylsulfonylacetamide) Ethane, etc.), N-methylol hardeners (dimethylolurea, etc.), boric acid, metaboric acid or polymer hardeners (compounds described in JP-A-62-234157). When gelatin is used as the aqueous compound, it is preferable to use a vinyl sulfone type hardener or a chlorotriazine type hardener alone or in combination. Moreover, when using polyvinyl alcohol, it is preferable to use boron-containing compounds such as boric acid and metaboric acid.

  These hardeners are used in an amount of 0.001 to 1 g, preferably 0.005 to 0.5 g, per 1 g of the aqueous compound. In addition, it is possible to perform heat treatment and humidity adjustment during the curing reaction in order to increase the film strength.

(Electronic insulation layer)
In the display element of the present invention, an electrical insulating layer can be provided.

  The electronic insulating layer applicable to the present invention may be a layer having both ionic conductivity and electronic insulating properties. For example, a solid electrolyte membrane in which a polymer or salt having a polar group is formed into a film, electronic insulating properties And a porous solid body having a low relative dielectric constant such as a silicon-containing compound, and the like.

  The porous film can be formed by a sintering method (fusion method) (using fine particles or inorganic particles added to a binder or the like and partially fused to make use of pores formed between the particles), extraction method ( After forming a constituent layer with a solvent-soluble organic or inorganic substance and a binder that does not dissolve in the solvent, the organic or inorganic substance is dissolved with the solvent to obtain pores), and the polymer is heated or degassed Well-known formation methods such as foaming method for foaming, phase change method for phase separation of polymer mixture by manipulating good solvent and poor solvent, and radiation irradiation method for forming pores by radiating various radiations Can be used. Specifically, JP-A-10-30181, JP-A-2003-107626, JP-B-7-95403, JP-A-2635715, JP-A-2894523, JP-A-2987474, JP-A-3066426, and JP-A-3464513. No. 3,483,464, No. 3535942, No. 30622203, and the like.

[Other additives]
Examples of the constituent layers of the display element of the present invention include auxiliary layers such as a protective layer, a filter layer, an antihalation layer, a crossover light cut layer, and a backing layer. Sensitizer, noble metal sensitizer, photosensitive dye, supersensitizer, coupler, high boiling point solvent, antifoggant, stabilizer, development inhibitor, bleach accelerator, fixing accelerator, color mixing inhibitor, formalin scavenger, Toning agents, hardeners, surfactants, thickeners, plasticizers, slip agents, UV absorbers, anti-irradiation dyes, filter light absorbing dyes, anti-bacterial agents, polymer latex, heavy metals, antistatic agents, matting agents Etc. can be contained as required.

  These additives mentioned above are more specifically described in Research Disclosure (hereinafter abbreviated as RD), Volume 176 Item / 17643 (December 1978), Volume 184, Item / 18431 (August 1979), 187. Volume Item / 18716 (November 1979) and Volume 308 Item / 308119 (December 1989).

  The types of compounds and their descriptions shown in these three research disclosures are listed below.

Additive RD17643 RD18716 RD308119
Page Classification Page Classification Page Classification Chemical sensitizer 23 III 648 Upper right 96 III
Sensitizing dye 23 IV 648-649 996-8 IV
Desensitizing dye 23 IV 998 IV
Dye 25-26 VIII 649-650 1003 VIII
Development accelerator 29 XXI 648 Upper right Anti-fogging agent / stabilizer
24 IV 649 Upper right 1006-7 VI
Brightener 24 V 998 V
Hardener 26 X 651 Left 1004-5 X
Surfactant 26-7 XI 650 Right 1005-6 XI
Antistatic agent 27 XII 650 Right 1006-7 XIII
Plasticizer 27 XII 650 Right 1006 XII
Slipper 27 XII
Matting agent 28 XVI 650 Right 1008-9 XVI
Binder 26 XXII 1003-4 IX
Support 28 XVII 1009 XVII
〔substrate〕
Examples of the substrate that can be used in the present invention include polyolefins such as polyethylene and polypropylene, polycarbonates, cellulose acetate, polyethylene terephthalate, polyethylene dinaphthalene dicarboxylate, polyethylene naphthalates, polyvinyl chloride, polyimide, and polyvinyl acetal. Synthetic plastic films such as polystyrene can also be preferably used. Syndiotactic polystyrenes are also preferred. These can be obtained, for example, by the methods described in JP-A Nos. 62-117708, 1-46912 and 1-178505. Further, a metal substrate such as stainless steel, a paper support such as baryta paper and resin coated paper, and a support provided with a reflective layer on the plastic film, supported by JP-A-62-253195 (pages 29 to 31) The thing described as a body is mentioned. RDNo. 17643, page 28, ibid. No. 18716, page 647, right column to page 648, left column, and No. 307105, page 879 can also be preferably used. As these supports, those having resistance to curling due to heat treatment of Tg or less as in US Pat. No. 4,141,735 can be used. Further, the surface of these supports may be subjected to surface treatment for the purpose of improving the adhesion between the support and other constituent layers. In the present invention, glow discharge treatment, ultraviolet irradiation treatment, corona treatment, and flame treatment can be used as the surface treatment. Furthermore, the support body described in pages 44 to 149 of publicly known technology No. 5 (issued by Aztec Co., Ltd. on March 22, 1991) can also be used. Furthermore, RDNo. 308119, page 1009, Product Licensing Index, Volume 92, P108, “Supports”, and the like. In addition, a glass substrate or an epoxy resin kneaded with glass can be used.

[Other components of the display element]
In the display element of the present invention, a sealant, a columnar structure, and spacer particles can be used as necessary.

  Sealing agent is for sealing so that it does not leak outside and is also called sealing agent. Epoxy resin, urethane resin, acrylic resin, vinyl acetate resin, ene-thiol resin, silicon resin, modified resin A curing type such as a polymer resin, such as a thermosetting type, a photocurable type, a moisture curable type, and an anaerobic curable type can be used.

  The columnar structure provides strong self-holding (strength) between the substrates, for example, a columnar body, a quadrangular columnar body, an elliptical columnar body, a trapezoidal array arranged in a predetermined pattern such as a lattice arrangement. A columnar structure such as a columnar body can be given. Alternatively, stripes arranged at predetermined intervals may be used. This columnar structure is not a random array, but can be properly maintained at intervals of the substrate, such as an evenly spaced array, an array in which the interval gradually changes, and an array in which a predetermined arrangement pattern is repeated at a constant period. The arrangement is preferably considered so as not to disturb the display. If the ratio of the area occupied by the columnar structure in the display area of the display element is 1 to 40%, a practically sufficient strength as a display element can be obtained.

  A spacer may be provided between the pair of substrates for uniformly maintaining a gap between the substrates. Examples of the spacer include a sphere made of resin or inorganic oxide. Further, a fixed spacer having a surface coated with a thermoplastic resin is also preferably used. In order to hold the gap between the substrates uniformly, only the columnar structure may be provided, but both the spacer and the columnar structure may be provided, or instead of the columnar structure, only the spacer is used as the space holding member. May be used. The diameter of the spacer is equal to or less than the height of the columnar structure, preferably equal to the height. When the columnar structure is not formed, the diameter of the spacer corresponds to the thickness of the cell gap.

[Display element driving method]
The method for controlling the transparent state and the colored state of the display element of the present invention is preferably determined based on the oxidation-reduction potential of the compound represented by the general formula (L) and the deposition overvoltage of metal ions.

  For example, in the case of a display element having a compound represented by the general formula (L) and a silver salt compound between counter electrodes, a colored state other than black is shown on the oxidation side and a black state is shown on the reduction side. As an example of the control method in this case, by applying a noble voltage from the oxidation-reduction potential of the compound represented by the general formula (L), the compound represented by the general formula (L) is oxidized and other than black Shows a colored state and reduces the compound represented by the general formula (L) to a white state by applying a voltage between the redox potential of the compound represented by the general formula (L) and the precipitation overvoltage of the silver compound. By applying a voltage lower than the deposition overvoltage of the silver compound, silver is deposited on the electrode to show a black state. The oxidation potential of the deposited silver and the oxidation-reduction potential of the compound represented by the general formula (L) The method of melt | dissolving and decoloring silver which precipitated by applying the voltage between is mentioned.

  The driving operation of the display element of the present invention may be simple matrix driving or active matrix driving. The simple matrix driving in the present invention is a driving method in which a current is sequentially applied to a circuit in which a positive line including a plurality of positive electrodes and a negative electrode line including a plurality of negative electrodes are opposed to each other in a vertical direction. Say that. By using simple matrix driving, there is an advantage that the circuit configuration and driving IC can be simplified and manufactured at low cost. The active matrix drive is a system in which scanning lines, data lines, and current supply lines are formed in a grid pattern, and are driven by TFT circuits provided in each grid pattern. Since switching can be performed for each pixel, there are advantages such as gradation and memory function. For example, a circuit described in FIG. 5 of JP-A-2004-29327 can be used.

[Product application]
The display element of the present invention can be used in an electronic book field, an ID card field, a public field, a traffic field, a broadcast field, a payment field, a distribution logistics field, and the like. Specifically, keys for doors, student ID cards, employee ID cards, various membership cards, convenience store cards, department store cards, vending machine cards, gas station cards, subway and railway cards, bus cards, Cash cards, credit cards, highway cards, driver's licenses, hospital examination cards, electronic medical records, health insurance cards, Basic Resident Registers, passports, electronic books, etc.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

Example << Preparation of display element >>
(Preparation of electrolyte 1)
Electrolyte 1 was prepared by dissolving 0.1 g of bismuth chloride, 0.2 g of lithium bromide, and 0.025 g of tetrabutylammonium perchlorate in 2.5 g of dimethyl sulfoxide.

(Preparation of electrolyte 2)
Electrolyte 2 was prepared by dissolving 0.1 g of silver p-toluenesulfonate and 0.025 g of tetrabutylammonium perchlorate in 2.5 g of dimethyl sulfoxide.

(Preparation of electrolyte 3)
In 2.5 g of γ-butyrolactone, 0.025 g of spiro- (1,1 ′)-bipyrrolidinium tetrafluoroborate, carboxy TEMPO (4-carboxy-2,2,6,6-tetramethylpiperidine-1-oxyl free Radical) 0.05 g, silver p-toluenesulfonate 0.1 g, and 3,6-dithia-1,8-octanediol 0.2 g were dissolved to prepare an electrolyte 3.

(Preparation of electrolyte 4)
In 2.5 g of γ-butyrolactone, 0.025 g of spiro- (1,1 ′)-bipyrrolidinium tetrafluoroborate and carboxy TEMPO (4-carboxy-2,2,6,6-tetramethylpiperidine-1-oxyl free Radical) 0.05 g, silver p-toluenesulfonate 0.1 g, and 3-mercapto-1,2,4-triazole 0.2 g were dissolved to prepare an electrolyte 4.

(Preparation of electrolyte 5)
In 2.5 g of γ-butyrolactone, 0.025 g of spiro- (1,1 ′)-bipyrrolidinium tetrafluoroborate, carboxy TEMPO (4-carboxy-2,2,6,6-tetramethylpiperidine-1-oxyl free The electrolyte 5 was prepared by dissolving 0.05 g of radicals.

(Preparation of electrolyte 6)
Electrolyte 6 was prepared by dissolving 0.5 g of the following heptyl viologen and 0.0025 g of nitric acid in 2.5 g of 2-methoxyethanol.

(Preparation of treatment liquid 1)
To a place where 0.02 g of acetic acid, 1 g of pure water and 1 g of methanol are being stirred, a solution obtained by dissolving 0.01 g of the following compound (1) in 0.15 g of methanol is added dropwise, and stirred at room temperature for about 1 hour to treat the solution 1 was prepared.

(Preparation of treatment liquid 2)
To a place where 20 g of pure water was being stirred, 0.1 g of 3-aminopropyltrimethoxysilane was added dropwise and stirred for about 1 hour at room temperature to prepare a treatment liquid 2.

(Preparation of treatment liquid 3)
Treatment liquid 3 was prepared by dissolving 0.025 g of the following compound (2) and 0.032 g of 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride in 1 g of dimethylformamide.

(Preparation of treatment liquid 4)
The said compound (2) was melt | dissolved in acetonitrile / ethanol so that it might become 3 mmol / l, and the processing liquid 4 was prepared.

(Preparation of treatment liquid 5)
A treatment solution 5 was prepared by dissolving 0.041 g of the following compound (3) and 0.032 g of 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride in 1 g of dimethylformamide.

(Preparation of electrode 1-1)
An ITO film having a pitch of 145 μm and an electrode width of 130 μm was formed on a 3 cm × 4.3 cm glass substrate having a thickness of 1.5 mm according to a known method to obtain a transparent electrode. A titanium dioxide layer having a thickness of 5 μm (about 4 to 10 particles having an average particle diameter of 17 nm was necked) was formed on the transparent electrode, and an electrode 1-1 was produced.

(Preparation of electrode 1-2)
The electrode 1-1 immersed in the electrolyte 1 is used as a cathode, the platinum plate is used as an anode, and a constant voltage of 1.5 V is applied for 5 seconds to deposit bismuth on the electrode 1-1. Thereafter, the electrode is washed with dimethyl sulfoxide. 1-7 was produced. When this electrode was observed from both the front and back sides, it was found that bismuth was mainly deposited on the ITO film.

(Preparation of electrode 1-3)
The treatment liquid 1 was placed on the titanium dioxide layer of the electrode 1-2 and placed at about 100 mg / cm ² and allowed to stand at room temperature for about 1 hour, washed with ethanol and water, and then heated at 100 ° C. for about 1 hour. -3 was produced.

(Preparation of electrode 1-4)
An electrode 1-3 immersed in the electrolyte 1 is used as an anode, a platinum plate is used as a cathode, a constant voltage of 1.5 V is applied for 10 seconds, bismuth on the electrode 1-3 is dissolved, and then the electrode is washed with dimethyl sulfoxide. 1-4 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (1) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-5)
The electrode 1-2 was immersed in the treatment liquid 2 and allowed to stand at room temperature for about 1 hour, then washed with ethanol and water, subsequently heated at 100 ° C. for about 1 hour, and then allowed to cool. Next, the treatment liquid 3 was placed on the titanium dioxide layer at about 100 mg / cm ² and allowed to stand at room temperature for about 3 hours, and then washed with ethanol and water to produce an electrode 1-5.

(Preparation of electrode 1-6)
The electrode 1-5 immersed in the electrolyte 1 is used as an anode, a platinum plate is used as a cathode, a constant voltage of 1.5 V is applied for 10 seconds, bismuth on the electrode 1-5 is dissolved, and then the electrode is washed with dimethyl sulfoxide. 1-6 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (2) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-7)
The electrode 1-1 immersed in the electrolyte 2 is used as the cathode, the silver plate is used as the anode, and a constant voltage of 1.5 V is applied for 5 seconds to deposit silver on the electrode 1-1, and then the electrode is washed with dimethyl sulfoxide. 1-7 was produced. When this electrode was observed from both the front and back sides, it was found that silver was mainly deposited on the ITO film.

(Preparation of electrode 1-8)
The treatment liquid 1 was placed on the titanium dioxide layer of the electrode 1-7 at about 100 mg / cm ² , allowed to stand at room temperature for about 1 hour, washed with ethanol and water, and then heated at 100 ° C. for about 1 hour. -8 was produced.

(Preparation of electrode 1-9)
The electrode 1-9 immersed in the electrolyte 2 is used as an anode, the platinum plate is used as a cathode, a constant voltage of 1.5 V is applied for 10 seconds, silver on the electrode 1-9 is dissolved, and then the electrode is washed with dimethyl sulfoxide. 1-9 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (1) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-10)
The electrode 1-7 was immersed in the treatment liquid 2 and allowed to stand at room temperature for about 1 hour, washed with ethanol and water, subsequently heated at 100 ° C. for about 1 hour, and then allowed to cool. Next, about 100 mg / cm ^{2 of the} treatment liquid 3 was placed on the titanium dioxide layer and allowed to stand at room temperature for about 3 hours, and then washed with ethanol and water to produce an electrode 1-10.

(Preparation of electrode 1-11)
The electrode 1-10 immersed in the electrolyte 2 is used as an anode, a platinum plate is used as a cathode, a constant voltage of 1.5 V is applied for 10 seconds, silver on the electrode 1-11 is dissolved, and then the electrode is washed with dimethyl sulfoxide. 1-11 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (2) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-12)
The treatment liquid 4 was placed on the titanium dioxide layer of the electrode 1-7 at about 100 mg / cm ² , allowed to stand at room temperature for about 1 hour, and then washed with ethanol to produce an electrode 1-12.

(Preparation of electrode 1-13)
The electrode 1-12 immersed in the electrolyte 2 is used as an anode, a platinum plate is used as a cathode, a constant voltage of 1.5 V is applied for 10 seconds, silver on the electrode 1-12 is dissolved, and then washed with dimethyl sulfoxide. 1-13 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (2) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-14)
The electrode 1-1 immersed in the electrolyte 6 is used as a cathode, the platinum plate is used as an anode, and a constant voltage of 2.5 V is applied for 5 seconds to deposit heptyl viologen on the electrode 1-1. 1-14 was produced. When this electrode was observed from both the front and back surfaces, it was found that heptyl viologen was mainly deposited on the ITO film.

(Preparation of electrode 1-15)
The treatment liquid 1 was placed on the titanium dioxide layer of the electrode 1-14 at about 100 mg / cm ² , allowed to stand at room temperature for about 1 hour, washed with ethanol and water, and then heated at 100 ° C. for about 1 hour. -15 was produced.

(Preparation of electrode 1-16)
The electrode 1-15 immersed in the electrolyte 6 is used as the anode, the platinum plate is used as the cathode, and a constant voltage of 2.5 V is applied for 10 seconds to dissolve the heptyl viologen on the electrode 1-15, and the electrode is then washed with ethanol. 1-16 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (1) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-17)
The electrode 1-7 was immersed in the treatment liquid 2 and allowed to stand at room temperature for about 1 hour, washed with ethanol and water, subsequently heated at 100 ° C. for about 1 hour, and then allowed to cool. Next, the treatment liquid 5 was placed on the titanium dioxide layer at about 100 mg / cm ² and allowed to stand at room temperature for about 3 hours, and then washed with ethanol and water to produce an electrode 1-17.

(Preparation of electrode 1-18)
The electrode 1-17 immersed in the electrolyte 2 is used as an anode, a platinum plate is used as a cathode, a constant voltage of 1.5 V is applied for 10 seconds, silver on the electrode 1-17 is dissolved, and then washed with dimethyl sulfoxide. 1-18 was produced. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (3) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 1-19)
The electrode 1-1 was immersed in an isopropanol solution containing 2% by mass of polyvinyl alcohol (average polymerization degree 3500, saponification degree 87%) for 30 minutes, washed with running water for 10 seconds, and then dried at 50 ° C. for 30 minutes. After evaporating, the electrode was dried in an atmosphere at 85 ° C. for 1 hour to produce an electrode 1-19.

(Preparation of electrode 1-20)
The electrode 1-19 was immersed in the treatment liquid 2 and allowed to stand at room temperature for about 1 hour, washed with ethanol and water, subsequently heated at 100 ° C. for about 1 hour, and then allowed to cool. Next, the treatment liquid 5 was placed on the titanium dioxide layer at about 100 mg / cm ² and allowed to stand at room temperature for about 3 hours, followed by washing with ethanol and water to produce an electrode 1-20.

(Preparation of electrode 1-21)
Electrode 1-20 was immersed in water, heated at 85 ° C. for 1 hour to dissolve the polyvinyl alcohol on electrode 1-20, and then washed with water to produce electrode 1-21. When this electrode was observed from both the front and back surfaces, it was found that the electrochromic compound derived from the compound (3) was mainly fixed to the titanium dioxide layer.

(Preparation of electrode 2)
A nickel electrode having an electrode thickness of 0.1 μm, a pitch of 145 μm, and an electrode interval of 130 μm is formed on a glass substrate having a thickness of 1.5 mm and a size of 2 cm × 4 cm by using a known method. A gold-nickel electrode (electrode 2) having a depth of 0.05 μm replaced with gold from the electrode surface was prepared.

(Preparation of electrode 3-1)
The treatment liquid 1 was placed on the titanium dioxide layer of the electrode 1-1 and placed at about 100 mg / cm ² and allowed to stand at room temperature for about 1 hour, then washed with ethanol and water, and then heated at 100 ° C. for about 1 hour. -1 was produced.

(Preparation of electrode 3-2)
The electrode 1-1 was immersed in the treatment liquid 2 and allowed to stand at room temperature for about 1 hour, washed with ethanol and water, subsequently heated at 100 ° C. for about 1 hour, and then allowed to cool. Next, about 100 mg / cm ^{2 of the} treatment liquid 3 was placed on the titanium dioxide layer and allowed to stand at room temperature for about 3 hours, and then washed with ethanol and water to prepare an electrode 3-2.

(Preparation of electrode 3-3)
The electrode 1-1 was immersed in the treatment liquid 2 and allowed to stand at room temperature for about 1 hour, washed with ethanol and water, subsequently heated at 100 ° C. for about 1 hour, and then allowed to cool. Next, about 100 mg / cm ^{2 of the} treatment liquid 5 was placed on the titanium dioxide layer and allowed to stand at room temperature for about 3 hours, and then washed with ethanol and water to prepare an electrode 3-3.

(Preparation of display element 1: present invention)
On the periphery of the electrode 2 bordered with an olefin-based sealant containing 10% glass spherical bead spacers with an average particle diameter of 40 μm as a volume fraction, polyvinyl alcohol (average polymerization degree 3500, saponification degree 87% ) 20% by mass of Titanium Dioxide CR-90 manufactured by Ishihara Sangyo Co., Ltd. was added to 2% by mass of isopropanol solution, and the mixed liquid dispersed with an ultrasonic disperser was applied so that the film thickness after drying was 20 μm. Then, after drying at 50 ° C. for 30 minutes to evaporate the solvent, it was dried in an atmosphere at 85 ° C. for 1 hour. After sprinkling glass spherical bead spacers having an average particle diameter of 20 μm on the obtained titanium dioxide layer, the electrode 2 and the electrode 1-4 were bonded together and heated and pressed to prepare an empty cell. The electrolyte 1 was vacuum-injected into the empty cell, and the injection port was sealed with an epoxy-based ultraviolet curable resin to produce a display element 1.

(Preparation of display element 2: the present invention)
Display element 2 was produced in the same manner as display element 1 except that electrode 1-6 was used instead of electrode 1-4, and electrolyte 3 was used instead of electrolyte 1.

(Preparation of Display Element 3: Present Invention)
A display element 3 was produced in the same manner as the display element 1 except that the electrode 1-3 was used instead of the electrode 1-4.

(Preparation of display element 4: present invention)
A display element 4 was produced in the same manner as the display element 1 except that the electrode 1-9 was used instead of the electrode 1-4 and the electrolyte 3 was used instead of the electrolyte 1.

(Preparation of display element 5: present invention)
A display element 5 was produced in the same manner as the display element 4 except that the electrode 1-11 was used instead of the electrode 1-9.

(Preparation of display element 6: present invention)
A display element 6 was produced in the same manner as the display element 4 except that the electrode 1-10 was used instead of the electrode 1-9.

(Preparation of display element 7: present invention)
A display element 7 was produced in the same manner as the display element 4 except that the electrolyte 4 was used instead of the electrolyte 3.

(Preparation of display element 8; present invention)
A display element 8 was produced in the same manner as the display element 7 except that the electrode 1-18 was used instead of the electrode 1-9.

(Preparation of display element 9: present invention)
A display element 9 was produced in the same manner as the display element 7 except that the electrode 1-10 was used instead of the electrode 1-9.

(Preparation of Display Element 10: Present Invention)
A display element 10 was produced in the same manner as the display element 7 except that the electrode 1-13 was used instead of the electrode 1-9.

(Preparation of display element 11: present invention)
A display element 11 was produced in the same manner as the display element 7 except that the electrode 1-16 was used instead of the electrode 1-9.

(Preparation of display element 12: comparative example)
A display element 12 was produced in the same manner as the display element 2 except that the electrode 3-1 was used instead of the electrode 1-6.

(Preparation of display element 13: comparative example)
A display element 13 was produced in the same manner as the display element 7 except that the electrode 3-2 was used instead of the electrode 1-9.

(Preparation of display element 14: present invention)
A display element 14 was produced in the same manner as the display element 4 except that the electrolyte 5 was used instead of the electrolyte 3.

(Preparation of display element 15: present invention)
A display element 15 was produced in the same manner as the display element 14 except that the electrode 1-16 was used instead of the electrode 1-9.

(Preparation of display element 16: comparative example)
A display element 16 was produced in the same manner as the display element 14 except that the electrode 3-3 was used instead of the electrode 1-9.

(Preparation of display element 17: present invention)
A display element 17 was produced in the same manner as the display element 14 except that the electrode 1-21 was used instead of the electrode 1-16.

(Preparation of display element 18: present invention)
A display element 18 was produced in the same manner as the display element 1 except that the electrode 1-11 was used instead of the electrode 1-4.

<< Evaluation of display element >>
(Display speed)
With respect to the display elements 1 to 13 and the display element 18, the display speed was evaluated as follows.

The wavelength when both electrodes of the display element are connected to both terminals of the constant voltage power supply, a voltage of +1.5 V is applied to the transparent electrode side for 1.5 seconds, and then a voltage of -1.5 V is applied for 1 second. The reflectance (R _black ) at 550 nm and the reflectance (R _white ) at a wavelength of 550 nm in the white state are measured with a spectrocolorimeter CM-3700d manufactured by Konica Minolta Sensing Co., Ltd., and the value of R _black / R _white is calculated. It was used as an indicator of display speed. The smaller this value, the faster the display speed.

  For the display elements 14 to 17, the display speed was evaluated as follows.

When both electrodes of the manufactured display element are connected to both terminals of a constant voltage power source, a voltage of -1.5 V is applied to the transparent electrode side for 1.5 seconds, and then a voltage of +1.5 V is applied for 0.5 seconds The reflectance (R _color ) at the maximum absorption wavelength in the visible light region and the reflectance at the same wavelength in the white state (R _white ) are measured with a spectrocolorimeter CM-3700d manufactured by Konica Minolta Sensing Co., Ltd. The value of _color / R _white was used as an indicator of display speed. The smaller this value, the faster the display speed.

  The evaluation results are shown in Table 1.

  From the table, it can be seen that the display element of the present invention has a higher display speed than the comparative example. Further, when the display element 15 and the display element 17 are compared, it can be seen that the display speed is high when a material that can be electrochemically deposited and / or dissolved is used as the coating layer. When the display element 1 and the display element 3 are compared, it can be seen that the display speed is high when the coating layer is dissolved after the electrochromic compound is fixed. The same can be seen by comparing the display element 7 and the display element 9. Comparing the display element 2 and the display element 11, it can be seen that the display speed is high when a metal is used as the coating layer. When the display element 1 and the display element 18 are compared, it can be seen that the display speed is high when the coating layer is made of the same element as the metal of the metal salt compound contained in the electrolyte layer.

1 Substrate (eg glass)
2 Transparent conductive layer (eg ITO)
3 Porous layer (eg TiO ₂ )
4 Electrolyte containing metal salt compound 5 Electrode (eg, silver)
6 Covering layer (eg silver)
7 Electrochromic compound solution 8 Electrochromic compound 9 Power supply

Claims (10)

  An electrolyte layer containing at least an electrolyte is provided between a pair of counter electrodes, and at least one of the counter electrodes is a display side electrode formed by laminating a conductive layer and a porous layer, and a part of the display side electrode A display element to which an electrochromic compound is fixed, wherein the display side electrode is formed by forming a coating layer that inhibits the fixing of the electrochromic compound on a part thereof, and then fixing the electrochromic compound. A display element.   The display element according to claim 1, wherein the covering layer is formed by forming an electrochemically deposited and / or soluble substance as a covering layer.   The display element according to claim 1, wherein the display-side electrode is obtained by fixing the electrochromic compound and further dissolving the coating layer.   The display element according to claim 1, wherein the coating layer is made of a metal.   The said electrolyte layer contains a metal salt compound, and performs black display, white display, and colored display other than black by the drive operation of a counter electrode, The any one of Claims 1-4 characterized by the above-mentioned. Display element.   6. The display element according to claim 5, wherein the coating layer is made of metal, and the metal of the coating layer is made of the same element as the metal of the metal salt compound.   The display element according to claim 5, wherein the metal salt compound is a silver salt compound.   The display element according to claim 1, wherein the electrochromic compound is fixed to the display-side electrode through a silanol bond. The display device according to claim 1, wherein the electrochromic compound is a compound represented by the following general formula (L).

(Wherein Rl ₁ represents a substituted or unsubstituted aryl group, Rl ₂ and Rl ₃ each represent a hydrogen atom or a substituent, X represents> N-Rl ₄ , an oxygen atom or a sulfur atom, and Rl ₄ Represents a hydrogen atom or a substituent.)   An electrolyte layer containing at least an electrolyte between a pair of counter electrodes, and at least one of the counter electrodes is a display side electrode formed by laminating a conductive layer and a porous layer, and the display side electrode is electrochromic compound A method of manufacturing a display element in which at least a part of the display element is fixed, wherein the coating layer inhibits fixing of the electrochromic compound to a part of the display-side electrode by an electrochemical method by applying a voltage to the conductive layer And then fixing the electrochromic compound to the display-side electrode.