JP2010139540A - Display element and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display element that can be driven at a low voltage with a simple member configuration and is excellent in driving stability, and to provide a method for manufacturing the same. <P>SOLUTION: The display element has an electrolyte and an oxidation-reduction active substance layer between a pair of electrodes opposite to each other, the oxidation-reduction active substance layer is formed by immersing at least one electrode of the counter electrodes in a processing liquid containing at least (1) an oxidation-reduction active polymer, (2) a metal ion or a nonmetal ion, (3) a ligand, and (4) a precipitation accelerator. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an 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 keep an eye on the browsing means over time, and these actions are hardly human-friendly means. In general, light-emitting displays are known to suffer from eye fatigue due to flickering, inconvenient to carry, limited reading posture, need to focus on a static screen, and increase power consumption 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 complicated TFT circuit required 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-white contrast and black quality, and various methods have been disclosed (for example, see Patent Documents 1 to 5).

  In an EC display element, a method of fixing an electrochromic compound or an auxiliary compound that can be oxidized / reduced to an electrode is disclosed in order to improve display stability (see, for example, Patent Document 6).

As a result of examining the techniques disclosed in each of the above patent documents in detail, the present inventor has a problem in the stability of reflectance when repeatedly driving when a compound having no fixing group is used. Turned out to be. Further, when a compound having a fixing group such as a silanol group or a phosphate group is used, the stability of the reflectance when repeatedly driven is improved, but there is a problem that usable compounds are limited. .
International Publication No. 04/068231 Specification International Publication No. 04/066733 U.S. Pat. No. 4,240,716 Japanese Patent No. 3428603 JP 2003-241227 A JP 2008-111941 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 that can be driven with a simple member configuration, a low voltage, and has excellent driving stability, and a method for manufacturing the display element.

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

  1. An electrolyte and a redox active substance layer are provided between a pair of counter electrodes, and the redox active substance layer includes at least 1) a redox active polymer, 2) a metal ion or a nonmetal ion, and 3) a coordination. A display element, wherein the counter element is formed by immersing at least one electrode of the counter electrode in a treatment liquid containing a substrate and 4) a deposition accelerator.

  2. 2. The display element according to 1 above, wherein the redox active material layer is formed on a non-display side electrode.

  3. 3. The display element as described in 1 or 2 above, wherein the electrolyte contains a metal salt compound and black display and white display are performed by driving the counter electrode.

  4). 4. The display element according to 3 above, wherein the metal salt compound is a silver salt compound.

  5. 5. The display element according to any one of 1 to 4, wherein the electrolyte contains a compound represented by the following general formula (G-1) or (G-2).

General formula (G-1)
_{Rg 11} -S-Rg _{12
Wherein, Rg 11,} Rg ₁₂ each represents a substituted or unsubstituted hydrocarbon group. Further, these hydrocarbon groups may contain one or more nitrogen atom, oxygen atom, phosphorus atom, sulfur atom or halogen atom, and Rg ₁₁ and Rg ₁₂ may be connected to each other to take a cyclic structure. ]

[Wherein, 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, and Rg ₂₁ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkylcarbonamide group, an arylcarbonamide group, an alkylsulfonamide group, an arylsulfonamide group, an alkoxy group, an aryl Oxy group, alkylthio group, arylthio group, alkylcarbamoyl group, arylcarbamoyl group, carbamoyl group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylsulfonyl group, alkoxycarbonyl group, Represents an aryloxycarbonyl group, an alkylcarbonyl group, an arylcarbonyl group, an acyloxy group, a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, Of Rg ₂₁ may be the same or different, and may be linked to each other to form a condensed ring. ]
6). 6. The display element according to any one of 1 to 5, wherein the redox active material layer contains SiO ₂ or TiO ₂ . The method for manufacturing a display element according to any one of 1 to 6,
A redox-active polymer; a complex formed from a metal ion or non-metal ion and a ligand; and a deposition accelerator that reacts with the ligand of the complex to precipitate a metal or non-metal oxide from the solution. A step of preparing a treatment liquid containing:
Immersing a substrate having an electrode in the treatment liquid to form a redox active substance layer on the electrode;
Using the substrate on which the redox active material layer is formed as at least one electrode and holding the redox active material layer and the electrolyte between a pair of opposed electrodes to produce a display element. A method for manufacturing a display element.

  According to the present invention, it is possible to provide a display element that can be driven with a simple member configuration, a low voltage, and has excellent driving stability, and a manufacturing method thereof.

  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 and a redox active substance layer between a pair of counter electrodes, and the redox active substance layer is at least 1) a redox active polymer. And 2) a metal ion or non-metal ion, 3) a ligand, and 4) a deposition accelerator, and formed by immersing at least one electrode of the counter electrode. It has been found that a display element that can be driven with a simple member configuration, a low voltage, and has excellent driving stability can be realized by the display element having the characteristics described above.

  Hereinafter, details of the display element and the manufacturing method thereof according to the present invention will be described.

[Basic structure of display element]
The display element of the present invention is a metal or non-metal oxide from a solution obtained by reacting a substrate having an electrode with a complex comprising a metal ion or non-metal ion and a ligand, and a ligand in the complex. The electrode having a redox active substance layer is formed by immersing the electrode in a treatment solution containing a deposition accelerator for precipitating a redox active substance layer on which the redox active polymer is immobilized. A display element that holds at least the redox active substance layer and the electrolyte between a pair of counter electrodes as an electrode, and by applying a voltage of positive and negative polarity between the counter electrodes, white display and black display, Alternatively, white display and colored display can be switched reversibly.

[Redox active substance layer]
The present invention is characterized in that an oxidation-reduction active substance layer to which an oxidation-reduction active polymer is fixed is provided on a display-side transparent electrode or a non-display-side electrode constituting a pair of counter electrodes.

  The redox active substance layer according to the present invention preferably has a nanoporous structure composed of fine particles and the like, and the ionic species contained in the electrolyte can move within the nanoporous structure. ing. For example, when the redox active material layer is provided on the display-side transparent electrode, it is desirable that the redox active material layer is substantially transparent when the display element is formed.

  The oxidation-reduction active substance layer according to the present invention is formed by immersing a substrate on which an electrode is formed in a treatment liquid containing an oxidation-reduction active polymer, a metal ion or non-metal ion, a ligand, and a precipitation accelerator. can do.

  As the redox active polymer that can be suitably used in the present invention, among electrochromic compounds and auxiliary compounds (promoters) described later, polymers that are high molecular compounds, or structures of low molecular electrochromic compounds and auxiliary compounds are used. Examples thereof include a polymer (for example, polyvinyl ferrocene) and the like in the molecule.

  Metal ions or non-metal ions applicable to the present invention can be appropriately selected depending on the type of oxide to be deposited. For example, metal ions such as Ti, Sn, Zn, Zr, Nb, V, and W can be used. It can be selected from each metal ion, and as the non-metal ion, it can be appropriately selected from non-metal ions such as Si, and Si, Ti, and W are preferable from the viewpoint of the stability of the precipitate.

Ligand according to the present invention, coordinated to a metal ion or nonmetal ions has intended to form a complex, for ^{_{example, F -, Cl -, ClO}} 4 -, SO 4 2-, OSO 4 4- and Can be mentioned. In the ligand according to the present invention, it is preferable to use F ⁻ from the viewpoint that it can form a complex with various metal ions or non-metal ions and the stability of the treatment liquid is good.

  As a solution of the complex in which a ligand is coordinated to a metal ion or a non-metal ion according to the present invention, for example, an aqueous ammonium fluoride titanate solution or an aqueous ammonium silicofluoride solution is commercially available, and these can be used. .

Precipitation accelerant agent according to the present invention, a ligand is coordinated to the metal ions or non-metallic ions are materials which form more stable complexes or compounds, e.g., Al, H ₃ BO ₃ and the like Are preferably used.

  In the formation of the redox active substance layer according to the present invention, the amount and shape of the precipitates can be adjusted by the concentration and temperature of the treatment liquid, the treatment time, and the like. Since the redox active material layer needs to keep the ionic species contained in the electrolyte in a movable state, it is necessary to control the amount and shape of the precipitates so as not to completely fill the voids. is there. The concentration, temperature, and treatment time of the treatment liquid may be set so as to satisfy such conditions. For example, the concentration is in the range of 0.01 to 1 mol / L, and the temperature is in the range of 5 to 98 ° C. The processing time may be set in the range of about 10 seconds to 24 hours. After completion of the treatment, it is preferable to sufficiently wash with water or the like.

  In order to satisfactorily disperse the redox active polymer, a surfactant or the like may be further added to the treatment liquid according to the present invention.

  The thickness of the redox active substance layer according to the present invention is preferably in the range of 0.1 to 10 μm, more preferably in the range of 0.25 to 5 μm.

[Method for manufacturing display element]
In the manufacturing method of the display element of the present invention,
1) Precipitation promotion in which a complex formed from a redox active polymer, a metal ion or non-metal ion and a ligand, and a ligand of the complex react with the complex to precipitate a metal or non-metal oxide from the solution. A step of preparing a treatment liquid containing an agent;
2) immersing a substrate having an electrode in the treatment liquid to form a redox active substance layer on the electrode;
3) using the substrate on which the redox active material layer is formed as at least one electrode, and manufacturing a display element by holding the redox active material layer and the electrolyte between a pair of opposed electrodes;
It is characterized by having.

  In the treatment liquid preparation step 1), for example, an aqueous ammonium fluoride titanate solution is used as a complex solution in which a ligand is coordinated to a metal ion or a non-metal ion, and boric acid is used as a precipitation accelerator. Prepare a mixed solution of aqueous solutions. Instead of the boric acid aqueous solution, a metal aluminum plate may be inserted into the ammonium fluoride titanate aqueous solution. Further, a dispersion in which polyvinyl ferrocene is dispersed as a redox active polymer in an aqueous solution of a surfactant (for example, sodium dodecylbenzenesulfonate) is added to this solution and stirred to disperse the redox active polymer. Prepare the solution.

  As a specific method of the step of forming the redox active substance layer according to 2), for example, ITO (Indium Tin Oxide, Indium Tin Oxide) is used as an electrode in a container containing the treatment liquid prepared in 1). ) A glass substrate on which a film is formed in a stripe shape by a known method is vertically inserted, and then left standing for a certain time in a suspended state. After pulling up the glass substrate from the treatment liquid, it is washed with pure water and dried. Next, a titanium dioxide dispersion is applied to the surface of the glass substrate having the electrode, and then heated to evaporate and dry the solvent to produce an electrode on which a redox active material layer is formed. The titanium dioxide dispersion can be obtained, for example, by adding a polyvinyl alcohol resin to a water / ethanol mixed solution and dissolving by heating, and then dispersing titanium dioxide particles with an ultrasonic disperser.

  Next, as a process for assembling the display element of the item 3), for example, after the periphery of the electrode formed with the redox active substance layer prepared in the item 2) is trimmed with a sealing agent containing glass spherical beads, A separately prepared ITO (Indium Tin Oxide) film is bonded to a glass substrate formed in a stripe shape in accordance with a known method and the stripe electrodes are orthogonally crossed, and further heated and pressed to empty cells. Is made. The display element of the present invention can be manufactured by injecting an electrolytic solution into the empty cell and sealing the injection port.

  Next, each component of the display element of the present invention will be described.

〔Electrolytes〕
The “electrolyte” as used in the present invention generally refers to a substance that dissolves in a solvent such as water and exhibits a 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”).

  As the supporting electrolyte that can be used in the display element of 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 are no particular limitations on the salts, and for example, inorganic ion salts such as alkali metal salts and alkaline earth metal salts; quaternary ammonium salts; cyclic quaternary ammonium salts; quaternary phosphonium salts and the like 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 _{^{6 -, AsF 6 -, CH}} 3 COO -, CH 3 (C 6 H 4) SO 3 -, and _{(C 2 F 5 SO 2)} 3 C - Li salt having a counter anion selected from, Na salt or 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,
Furthermore,

Etc.

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 - phosphonium salt having a counter anion selected from, specifically, _(CH 3) ₄ PBF ₄ , (C ₂ H ₅ ) ₄ PBF ₄ , (C ₃ H ₇ ) ₄ PBF ₄ , (C ₄ H ₉ ) ₄ PBF _{4 and the} like. Moreover, these mixtures can also be used suitably.

The supporting electrolyte of the present invention is preferably a 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 in general, 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. 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 exhibiting electronic conductivity and ionic 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. Fluorine-containing compounds such as chalcogenides, CaF ₂ , PbF ₂ , SrF ₂ , LaF ₃ , TlSn ₂ F ₅ , CeF ₃ , Li salts such as Li ₂ SO ₄ , Li ₄ SiO ₄ , Li ₃ PO ₄ , 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 _{7 Cl 13, Rb 3 Cu 7} Cl 10, LiN, compounds such as _{Li 5 NI 2, Li 6 NBr} 3 , and the like.

[Metal salt compounds]
The metal salt compound contained in the electrolyte according to the present invention is a salt containing a metal species that can be dissolved and precipitated by driving the counter electrode on at least one electrode on the counter electrode. Any compound may be used. Preferred metal species are silver, bismuth, copper, nickel, iron, chromium, zinc and the like, and particularly preferred are silver and bismuth.

[Silver salt compound]
In the present invention, the metal salt compound is preferably a 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 solution 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 solution is [X] (mol / kg), and the silver or silver contained in the electrolyte solution is a compound that contains silver in the chemical structure. When the total molar concentration of [Metal] (mol / kg) is satisfied, it is preferable that the condition defined by the following formula (1) is satisfied.

Formula (1): 0 ≦ [X] / [Metal] ≦ 0.1
The halogen atom as used in the field of this invention means an iodine atom, a chlorine atom, a bromine atom, and 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 solution. For example, coexisting with a compound containing a chemical structural species that interacts with silver, such as a coordinate bond with silver and a weak supply bond with silver, solubilized product of silver or a compound containing silver It is common to use a means for converting to. As the chemical species, a halogen atom, a mercapto group, a carboxyl group, an imino group, and the like are known. It is characterized by low influence on coexisting compounds and high solubility in solvents.

  In this invention, in order to accelerate | stimulate melt | dissolution precipitation of metal salt (especially silver salt), it is preferable to contain the compound represented by the following general formula (G-1) or general formula (G-2).

(Compound represented by General Formula (G-1) or General Formula (G-2))
In the display element of this invention, it is preferable that electrolyte contains at least 1 sort (s) of the compound represented by the following general formula (G-1) or general formula (G-2). The compounds represented by the general formulas (G-1) and (G-2) are compounds that promote the solubilization of silver in the electrolyte in order to cause dissolution and precipitation of silver in the present invention.

  In general, in order to cause dissolution and precipitation of silver, it is necessary to solubilize silver in the electrolyte. For example, silver that causes a coordinate bond with silver and a weak covalent bond with silver. A compound containing a chemical structural species that interacts with is useful. As the chemical structural 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 has a feature that it has little influence on coexisting compounds and high solubility in a solvent.

In the general formula (G-1), Rg ₁₁ and Rg ₁₂ each represent a substituted or unsubstituted hydrocarbon 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 form a cyclic structure.

In the general formula (G-2), 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, and Rg ₂₁ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkylcarbonamide group, an arylcarbonamide group, an alkylsulfonamide group, an arylsulfonamide group, an alkoxy group, an aryl Oxy group, alkylthio group, arylthio group, alkylcarbamoyl group, arylcarbamoyl group, carbamoyl group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylsulfonyl group, alkoxycarbonyl group, Represents an aryloxycarbonyl group, an alkylcarbonyl group, an arylcarbonyl group, an acyloxy group, a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, Of Rg ₂₁ may be the same or different, and may be linked to each other to form a condensed ring.

In the general formula (G-1), Rg ₁₁ and Rg ₁₂ each represent a substituted or unsubstituted hydrocarbon group. In these hydrocarbon groups, one or more nitrogen atoms, oxygen atoms, phosphorus atoms, sulfur An atom may be included, and Rg ₁₁ and Rg ₁₂ may be connected to each other to take a cyclic structure.

  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 General Formula (G-1) that can be applied in the present invention are shown below, but the present invention is not limited 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 =} ) CNHCH 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 ⁻

  Of the above-exemplified compounds, Exemplified Compounds G1-2 and G1-3 are 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 general formula (G2), 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, and Rg ₂₁ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkylcarbonamide group, an arylcarbonamide group, an alkylsulfonamide group, an arylsulfonamide group, an alkoxy group, an aryl Oxy group, alkylthio group, arylthio group, alkylcarbamoyl group, arylcarbamoyl group, carbamoyl group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylsulfonyl group, alkoxycarbonyl group, Represents an aryloxycarbonyl group, an alkylcarbonyl group, an arylcarbonyl group, an acyloxy group, a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, Of Rg ₂₁ may be the same or different, and may be linked to each other to form a condensed ring.

In the general formula (G2), examples of the metal atom represented by M include Li, Na, K, Mg, Ca, Zn, Ag, and the like. 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 etc. Can be mentioned.

  Examples of the nitrogen-containing heterocycle having Z as a constituent in 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.

In the general formula (G2), examples of the group represented by Rg ₂₁ include a 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.), arylcarbonamide groups (eg, benzoylamino, etc.), alkylsulfonamide groups (eg, methanesulfonylamino group, ethanesulfonylamino group, etc.), arylsulfonamide groups (eg, benzene Sulfonylamino group, toluenesulfonylamino group etc.), aryloxy group (eg phenoxy etc.), alkylthio group (eg methylthio, ethylthio, butylthio etc.), arylthio group (eg phenylthio group, tolylthio group etc.), alkylcarbamoyl group (Eg, methylcarbamoyl, dimethylcarbamoyl, ethylcarbamoyl, diethylcarbamoyl, dibutylcarbamoyl, piperidylcarbamoyl, morpholylcarbamoyl, etc.), arylcarbamoyl groups (eg, phenylcarbamoyl, methylphenylcarbamoyl, ethylphenylcarbamoyl, benzylphenylcarbamoyl, etc.), alkyl Sulfamoyl group (for example, methylsulfamoyl, dimethylsulfamoyl, ethylsulfamoyl, diethylsulfamo Yl, dibutylsulfamoyl, piperidylsulfamoyl, morpholylsulfamoyl, etc.), arylsulfamoyl groups (eg, phenylsulfamoyl, methylphenylsulfamoyl, ethylphenylsulfamoyl, benzylphenylsulfamoyl) Etc.), alkylsulfonyl groups (eg, methanesulfonyl group, ethanesulfonyl group, etc.), arylsulfonyl groups (eg, phenylsulfonyl, 4-chlorophenylsulfonyl, p-toluenesulfonyl, etc.) alkoxycarbonyl groups (eg, methoxycarbonyl, ethoxycarbonyl, etc.) , Butoxycarbonyl etc.), aryloxycarbonyl group (eg phenoxycarbonyl etc.), alkylcarbonyl group (eg acetyl, propionyl, butyroyl etc.), arylcarbonyl (For example, benzoyl group, alkylbenzoyl group, etc.), acyloxy group (for example, acetyloxy, propionyloxy, butyroyloxy, etc.), heterocyclic group (for example, oxazole ring, thiazole ring, triazole ring, selenazole ring, tetrazole ring, oxadiene) Azole ring, thiadiazole ring, thiazine ring, triazine ring, benzoxazole ring, benzthiazole ring, indolenine ring, benzselenazole ring, naphthothiazole ring, triazaindolizine ring, diazaindolizine ring, tetraazaindolizine ring Group). 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, Exemplified Compounds G2-12 and G2-18 are particularly preferable from the viewpoint that the object and effects of the present invention can be exhibited.

[Electrochromic compound]
An electrochromic compound having electrochromic characteristics can be used for the electrolyte solution according to the present invention.

  The electrochromic compound (EC compound) according to the present invention is not particularly limited as long as it exhibits an action of coloring or decoloring by at least one of an electrochemical oxidation reaction and a reduction reaction, and may be appropriately selected according to the purpose. it can. EC compounds include inorganic oxides such as tungsten oxide, iridium oxide, nickel oxide, cobalt oxide, vanadium oxide, molybdenum oxide, titanium oxide, indium oxide, chromium oxide, manganese oxide, Prussian blue, indium nitride, tin nitride, zirconium nitride chloride, etc. In addition to compounds, organometallic complexes, conductive polymer compounds, and organic dyes are known.

  Examples of the organometallic complex exhibiting electrochromic properties include metal-bipyridyl complexes, metal phenanthroline complexes, metal-phthalocyanine complexes, rare earth diphthalocyanine complexes, and ferrocene dyes.

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

  For example, a polymer material composed of a bisterpyridine derivative and a metal ion as described in JP-A-2007-112957 also exhibits electrochromic properties.

  Examples of organic dyes that exhibit electrochromic properties include pyridinium compounds such as viologen, azine dyes such as phenothiazine, styryl dyes, anthraquinone dyes, pyrazoline dyes, fluorane dyes, donor / acceptor compounds (for example, tetracyanoquino compounds) Dimethane, tetrathiafulvalene) and the like. In addition, compounds known as redox indicators and pH indicators can also be used.

(Classification of EC compounds by color tone)
The EC compounds according to the present invention 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.

As a compound classified into class 1, for example, V ₂ O ₅ changes from an orange state to a green color by changing from an oxidation state to a reduction state, and similarly Rh ₂ O ₃ changes from a yellow color to a dark green color.

  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, The color changes 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 multicolor characteristics and changes from an amber color in 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.

Examples of the inorganic compounds classified as class 2 include the following compounds, each of which shows the color shown in parentheses in the reduced state. WO ₃ (blue), MnO ₃ (blue), Nb ₂ O ₅ (blue), TiO ₂ (blue) and the like.

  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), 4,4'-biphenylcarboxylic acid. Examples thereof include diethyl (yellow), 1,4-diacetylbenzene (cyan), and tetrazolium salt compounds described in JP-A-1-230026, JP-T 2000-504964, and the like.

  The most typical compounds classified as class 2 are pyridinium compounds such as viologen. Viologen compounds have the advantages of vivid display and the ability to have color variations by changing substituents. Therefore, 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-2001-181292, JP-A-2001-181293, Table 2001-510590, JP-A-2004-101729, JP-A-2006-154683, JP-T-2006-519222, JP-A-2007-31708, 2007-171817, 2007-219271, 2007-219272, JP-T JP 2007-279659, JP 2007-279570, JP 2007-279571, JP 2007-279572, and the like.

  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 extremely pale in the reduced state and exhibit a specific colored state that is an oxidized state.

  Examples of inorganic compounds classified as class 3 include iridium oxide (dark blue), Prussian blue (blue), and the like (each exhibiting the color shown in parentheses in the oxidized state).

  There are few examples of conductive polymers classified into class 3, but examples 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 in particular, azoles in terms of color development diversity, low driving voltage, memory properties, and the like. System dyes are preferred.

[Compound represented by formula (L)]
In the present invention, the most preferred dye is a compound represented by the following 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, sriphoranyl 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, more preferably a substituted or unsubstituted 2-hydroxyphenyl group or 4-hydroxyphenyl group.

The substituent represented by R1 ₂ or Rl ₃ is not particularly limited, and examples thereof include the substituents exemplified as the substituent on the aryl group of Rl ₁ . Rl ₂ and Rl ₃ are preferably 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. The combination of Rl ₂ and Rl ₃ may be a phenyl group or a heterocyclic group, both of which may have a substituent, or Either one is a phenyl group or a heterocyclic group which may have a substituent, and the other is a combination of an alkyl group 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, the compound represented by the general formula (L) preferably has an adsorptive group that is chemically or physically adsorbed to the electrode surface. The chemical adsorption referred to in the present invention is a relatively strong adsorption state due to a chemical bond with the electrode surface, and the physical adsorption referred to in the present invention is a relatively strong van der Waals force acting between the electrode surface and the adsorbed substance. It is weakly adsorbed.

In the present invention, the adsorptive group is preferably a chemisorbable group, and as the adsorptive group to be chemisorbed, —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.

In the general formula (L2), Rl ₂₁ and Rl ₂₂ represent an aliphatic group, an aliphatic oxy group, an acylamino group, a carbamoyl group, an acyl group, a sulfonamide group, and a sulfamoyl group, and R1 ₂₃ represents an aromatic group or an aromatic group. R1 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, as its partial structure, —COOH, —P═O (OH) ₂ , —OP═O (OH) ₂ and —Si (OR) ₃ ( R represents an alkyl group.

In the general formula (L2), the group represented by Rl ₂₁ or 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.

In addition, when the compound represented by the general formula (L2) is fixed on the electrode, at least one of the groups represented by Rl _{21 to} Rl ₂₅ includes —P═O (OH) ₂ , —Si as a partial structure. It is preferable to have (OR) ₃ (R represents an alkyl group), and in particular, —Si (OR) ₃ (R represents an alkyl group) as a partial structure of the group represented by Rl ₂₃ or Rl _24. It is preferable to have.

  Specific examples of the EC dye represented by the general formula (L2) and specific examples of the EC dye included in the general formula (L) are shown below, although they do not correspond to the general formula (L2). Is not limited to these exemplified compounds.

  These electrochromic compounds are preferably immobilized on electrodes, particularly on the viewing side (display side). By fixing to the viewing side electrode, the viewing density can be improved.

[Auxiliary compound]
In the display device of the present invention, it is preferable to add an auxiliary compound that can be oxidized and reduced in order to promote the electrochemical reaction of the compound that is reversibly discolored by the electrochemical oxidation and reduction reaction. The auxiliary compound 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 may be one that changes, that is, an EC compound.

  In the display device of the present invention, a single auxiliary compound may be used, or a plurality of auxiliary compounds may be used in combination. In the present invention, when an auxiliary compound is used, it is preferably immobilized on the redox active substance layer.

  There is no restriction | limiting in particular as an auxiliary compound, According to the objective, it can select suitably. It is also possible to use the above EC compound as an auxiliary compound.

  Preferable auxiliary compounds that can be used in the present invention include, for example, the following compounds.

1) N-oxyl derivatives such as TEMPO (2,2,6,6-tetramethylpiperidinyl-N-oxyl), N-hydroxyphthalimide derivatives, hydroxamic acid derivatives, etc., compounds having an N—O bond ,
2) a compound having an allyloxy free radical having a bulky substituent introduced at the 0-position, such as galvinoxyl;
3) metallocene derivatives such as ferrocene,
4) benzyl (diphenylethanedione) derivative,
5) Tetrazolium salt / formazan derivative,
6) Azine compounds such as phenazine, phenothiazine, phenoxazine, acridine,
7) pyridinium compounds such as viologen,
In addition, 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, etc. can also be used as auxiliary compounds. it can.

  In the display device of the present invention, auxiliary compounds in the categories 1) to 7) are preferable, and 1) and 3) are particularly preferable.

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

[Organic solvent]
In the electrolyte according to the present invention, as a solvent, a metal salt compound that is generally used in an electrochemical cell or a battery and is reversibly dissolved and precipitated by an electrochemical redox reaction, including an electrochromic compound used in the present invention. A solvent capable of dissolving various additives such as a promoter can be used.

  Specifically, acetic anhydride, methanol, ethanol, tetrahydrofuran, ethylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, butylene carbonate, propylene carbonate, nitromethane, acetonitrile, acetylacetone, N-methylformamide, N, N-dimethylformamide , Dimethyl sulfoxide, hexamethylphosphoamide, dimethoxyethane, diethoxyfuran, γ-butyrolactone, γ-valerolactone, sulfolane, propionitrile, butyronitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, N-methylacetamide, N, N -Dimethylacetamide, N-methylpropionamide, methylpyrrolidinone, 2- (N-methyl) -2-pyrrolidi Non, dimethyl sulfoxide, dioxolane, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, ethyl dimethyl phosphate, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, tris (Trifluoromethyl) phosphate, tris (pentafluoroethyl) phosphate, triphenyl phosphate, tricresyl phosphate, 2-ethylhexyl phosphate, tetramethylurea, 1,3-dimethyl-2-imidazolidinone, hexamethylphosphotriamide 4-methyl-2-pentanone, dioctyl phthalate, dioctyl sebacate, and ethylene glycol Lumpur, diethylene glycol, polyethylene glycols such as triethylene glycol monobutyl ether and the like can be used.

  Furthermore, room temperature molten salts can also be used as solvents. The room temperature molten salt is a salt composed of ion pairs that are melted at room temperature (that is, in a liquid state) consisting only of ion pairs that do not contain a solvent component, and usually has a melting point of 20 ° C. or lower, A salt consisting of an ion pair that is liquid at a temperature above. The room temperature molten salt can be used alone or in combination of two or more.

  The electrolyte solvent used in the present invention is preferably an aprotic polar solvent, particularly propylene carbonate, ethylene carbonate, dimethyl sulfoxide, dimethoxyethane, acetonitrile, γ-butyrolactone, sulfolane, dioxolane, dimethylformamide, dimethoxyethane, tetrahydrofuran, adiponitrile, Methoxyacetonitrile, dimethylacetamide, methylpyrrolidinone, dimethyl sulfoxide, dioxolane, sulfolane, trimethyl phosphate and triethyl phosphate are preferred. The solvent may be used alone or in combination of two or more.

  In the present invention, particularly preferably used solvents are compounds represented by the following general formula (S1) or (S2).

  <Compounds Represented by General Formulas (S1) and (S2)>

In the general formula (S1), L represents an oxygen atom or an alkylene group, and Rs ₁₁ to Rs ₁₄ each represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a cycloalkyl group, an alkoxyalkyl group, or an alkoxy group.

In the general formula (S2), Rs ₂₁ and Rs ₂₂ each represents an alkyl group, an alkenyl group, an aryl group, a cycloalkyl group, an alkoxyalkyl group, or an alkoxy group.

  First, the detail of the compound represented by general formula (S1) is demonstrated.

In the general formula (S1), L represents an oxygen atom or CH ₂ , and Rs ₁₁ to Rs ₁₄ each represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a cycloalkyl group, an alkoxyalkyl group, or an alkoxy group, These substituents may be further substituted with an arbitrary substituent.

  Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, tert-butyl, pentyl, hexyl, octyl, dodecyl, tridecyl, tetradecyl, pentadecyl, and the like as aryl groups. Examples of the cycloalkyl group such as phenyl group, naphthyl group and the like include, for example, a cyclopentyl group, cyclohexyl group and the like, an alkoxyalkyl group, for example, a β-methoxyethyl group, a γ-methoxypropyl group and the like, as an alkoxy group, Examples thereof include a methoxy group, an ethoxy group, a propyloxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, and a dodecyloxy group.

  Hereinafter, although the specific example of a compound represented by general formula (S1) is shown, in this invention, it is not limited only to these illustrated compounds.

  Next, details of the compound represented by formula (S2) according to the present invention will be described.

In the general formula (S2), Rs ₂₁ and Rs ₂₂ each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a cycloalkyl group, an alkoxyalkyl group, or an alkoxy group.

  Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, tert-butyl, pentyl, hexyl, octyl, dodecyl, tridecyl, tetradecyl, pentadecyl, and the like as aryl groups. Examples of the cycloalkyl group such as phenyl group, naphthyl group and the like include, for example, a cyclopentyl group, cyclohexyl group and the like, an alkoxyalkyl group, for example, a β-methoxyethyl group, a γ-methoxypropyl group and the like, as an alkoxy group, Examples thereof include a methoxy group, an ethoxy group, a propyloxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, and a dodecyloxy group.

  Hereinafter, although the specific example of a compound represented by general formula (S2) is shown, in this invention, it is not limited only to these illustrated compounds.

  Of the compounds represented by the general formulas (S1) and (S2) exemplified above, the exemplary compounds (S1-1), (S1-2), and (S2-3) are particularly preferable.

  The compounds represented by the general formulas (S1) and (S2) according to the present invention are one type of electrolyte solvent. However, in the display element of the present invention, another solvent is used as long as the object effects of the present invention are not impaired. Can be used together. Specifically, tetramethylurea, sulfolane, dimethyl sulfoxide, 1,3-dimethyl-2-imidazolidinone, 2- (N-methyl) -2-pyrrolidinone, hexamethylphosphortriamide, N-methylpropionamide, N, N-dimethylacetamide, N-methylacetamide, N, N dimethylformamide, N-methylformamide, butyronitrile, propionitrile, acetonitrile, acetylacetone, 4-methyl-2-pentanone, 2-butanol, 1-butanol, 2 -Propanol, 1-propanol, ethanol, methanol, acetic anhydride, ethyl acetate, ethyl propionate, dimethoxyethane, diethoxyfuran, tetrahydrofuran, ethylene glycol, diethylene glycol, triethylene glycol monobuty Ether, water and the like. Among these solvents, it is preferable to include at least one solvent having a freezing point of −20 ° C. or lower and a boiling point of 120 ° C. or higher.

  Furthermore, as a solvent which can be used in the present invention, J.P. A. Riddick, W.M. B. Bunger, T.A. K. Sakano, “Organic Solvents”, 4th ed. , John Wiley & Sons (1986). Marcus, “Ion Solvation”, John Wiley & Sons (1985), C.I. Reichardt, “Solvents and Solvent Effects in Chemistry”, 2nd ed. VCH (1988), G .; J. et al. Janz, R.A. P. T.A. Tomkins, “Nonqueous Electronics Handbook”, Vol. 1, Academic Press (1972).

  In the present invention, the electrolyte solvent may be a single type or a mixture of solvents, but a mixed solvent containing ethylene carbonate is preferred. The addition amount of ethylene carbonate is preferably 10% by mass or more and 90% by mass or less of the total electrolyte solvent mass. A particularly preferable electrolyte solvent is a mixed solvent having a mass ratio of propylene carbonate / ethylene carbonate of 7/3 to 3/7. When the propylene carbonate ratio is larger than 7/3, the ionic conductivity is inferior and the response speed is lowered. When the propylene carbonate ratio is smaller than 3/7, the electrolyte tends to be deposited at a low temperature.

(Porous white scattering layer)
In the present invention, a porous white scattering layer containing a white scattering material can be provided from the viewpoint of further increasing display contrast and white display reflectance.

  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.

  In the present invention, “substantially insoluble in an electrolyte solvent” is defined as a state in which the dissolved amount per kg of electrolyte solvent is 0 g or more and 10 g or less at a temperature of −20 ° C. to 120 ° C. The amount of dissolution can be determined by a known method such as a component determination method using a chromatogram or a gas chromatogram.

  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, or cellulose derivatives, natural compounds such as starch, gum arabic, dextran, pullulan, and carrageenan polysaccharides, polyvinyl alcohol, polyethylene glycol, polyvinyl pyrrolidone, and acrylamide polymers. And synthetic polymer compounds such as derivatives thereof. As gelatin derivatives, acetylated gelatin, phthalated gelatin, polyvinyl alcohol derivatives as 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. Furthermore, Research Disclosure and those described in 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 (e.g., sodium methacrylate in the vinyl monomer having a methacrylic acid Copolymers with ammonium, potassium acrylate, etc.) are also used. These binders can be used in combination of two or more.

  In the present invention, polyvinyl alcohol, polyethylene glycol, and polyvinylpyrrolidone compounds can be preferably used.

  Polymers dispersed in aqueous solvents 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.

  The average molecular weight of the water-based polymer of the present invention is preferably in the range of 10,000 to 2,000,000, more preferably in the range of 30,000 to 500,000 on a weight average basis.

  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 is preferably used. In particular, titanium dioxide surface-treated with an inorganic oxide (Al ₂ O ₃ , AlO (OH), SiO _2, etc.), in addition to these surface treatments. Titanium dioxide that has been treated with an organic substance such as trimethylolethane, triethanolamine acetate, or trimethylcyclosilane is more preferably 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, 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.

  The thickness of the porous white scattering layer is preferably in the range of 5 to 50 μm, more preferably in the range of 10 to 30 μm.

  As the alcohol solvent, a compound having high solubility in water such as methanol, ethanol, isopropanol is preferably used, and the mixing ratio with the water / alcohol solvent is preferably in the range of 0.5 to 20 by mass ratio, More preferably, it is the range of 2-10.

  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.

  As a coating method, it can select suitably from a well-known coating method. For example, air doctor coater, blade coater, rod coater, knife coater, squeeze coater, impregnation coater, reverse roller coater, transfer roller coater, curtain coater, double roller coater, slide hopper coater, gravure coater, kiss roll coater, bead coater, Examples include 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 electronic 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.

  As a method for forming a porous film, a sintering method (fusing method) (using fine pores formed between particles by partially fusing polymer fine particles or inorganic particles by adding a binder, etc.), extraction method ( After forming a constituent layer with a solvent-soluble organic substance or inorganic substance and a binder that does not dissolve in the solvent, the organic substance or inorganic substance is dissolved with the solvent to obtain pores), and the polymer is heated or degassed Known forming methods such as a foaming method in which foaming is performed, a phase change method in which a mixture of polymers is phase-separated by operating a good solvent and a poor solvent, and a radiation irradiation method in which pores are formed by radiating various types of radiation 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.

[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 (epoxide) s, 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. Moreover, the compound as described in pages 71-75 of Unexamined-Japanese-Patent No. 64-13546 can be mentioned. 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.

  In the display element of the present invention, polyethylene glycol having an average degree of polymerization of 100 to 500 is preferable as the thickener, and it is preferably added in a range of 5 to 20% by mass ratio with respect to the organic solvent of the electrolyte.

[Other additives]
Various additives can be used for the electrolyte solution of the display element produced with the manufacturing method of the display element of this invention for the purpose of improving other various performances. They are selected according to the purpose and are not particularly limited.

  Various chemical sensitizers, noble metal sensitizers, photosensitive dyes, supersensitizers, couplers, high boiling point solvents, antifoggants, stabilizers, development inhibitors, bleach accelerators, fixing accelerators, color mixing inhibitors, Formalin Scavenger, Toning Agent, Hardener, Surfactant, Thickener, Plasticizer, Slipper, UV Absorber, Irradiation Dye, Filter Light Absorber Dye, Antibacterial Agent, Polymer Latex, Heavy Metal, Antistatic Agent Further, a matting agent and the like can be contained as necessary.

  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 1006-7XIII
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
The above additives may be provided in auxiliary layers such as a protective layer, a filter layer, an antihalation layer, a crossover light cut layer, and a backing layer, and may be contained in these auxiliary layers.

〔substrate〕
The substrate that can be used in the present invention is preferably a transparent substrate. Examples of such a transparent substrate include polyester (for example, polyethylene terephthalate), polyimide, polymethyl methacrylate, polystyrene, polypropylene, polyethylene, and polyamide. Nylon, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyether sulfone, silicone resin, polyacetal resin, fluororesin, cellulose derivative, polyolefin and other polymer films, plate substrates, glass substrates and the like are preferably used. The transparent substrate used in the present invention refers to a substrate having a transmittance for visible light of at least 50%.

  Further, as the counter substrate, for example, an opaque substrate such as an inorganic substrate such as a metal substrate or a ceramic substrate can be used.

〔electrode〕
(Transparent electrode)
In the display element of the present invention, it is preferable that at least one of the counter electrodes is a transparent electrode. The transparent electrode 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, and the like can be given. 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.

(Counter electrode pixel electrode)
The counter-side pixel electrode can be used without particular limitation as long as electricity can be passed. In addition to the same material as the transparent electrode, metals having no transparency such as platinum, gold, silver, copper, aluminum, zinc, nickel, titanium, bismuth and the like, alloys thereof, carbon and the like can be preferably used.

  As an electrode manufacturing method, an existing method such as an electrolytic plating method, an electroless plating method, a displacement plating method, a vapor deposition method, a printing method, an ink jet method, a spin coating method, or a CVD method can be used.

(Porous electrode)
A porous electrode having a nanoporous structure can be provided on the display-side transparent electrode or the counter electrode. This porous electrode can carry an electroactive substance such as an electrochromic dye. When it is provided on the display-side transparent electrode, it is desirable that it is substantially transparent when the display element is formed.

  The nanoporous structure as used in the present invention refers to a state in which an infinite number of nanometer-sized pores exist in a layer and ionic species contained in the electrolyte can move within the nanoporous structure.

  In order for the nanoporous electrode to have transparency, it is preferable to use fine particles having an average particle diameter of about 5 nm to 10 μm. As the shape of the fine particles, those having an arbitrary shape such as an indefinite shape, a needle shape, and a spherical shape can be used.

  As a method for forming such a nanoporous electrode, there is a method in which a dispersion containing fine particles constituting the nanoporous electrode is applied by an inkjet method, a screen printing method, a blade coating method or the like and then dried.

The main components of the fine particles constituting the nanoporous electrode are metals such as Cu, Al, Pt, Ag, Pd and Au, metal oxides such as ITO, SnO ₂ , TiO ₂ and ZnO, carbon nanotubes, glassy carbon, and diamond. It can be selected from carbon electrodes such as like carbon and nitrogen-containing carbon, and is preferably selected from metal oxides such as ITO, SnO ₂ , TiO ₂ , and ZnO.

  The film thickness of the nanoporous electrode is preferably in the range of 0.1 to 10 μm, more preferably in the range of 0.25 to 5 μm.

(Grid electrode: auxiliary electrode)
In the present invention, an auxiliary electrode can be attached to at least one of the counter electrodes.

  The auxiliary electrode is preferably made of a material having a lower electrical resistance than the main electrode portion. For example, metals such as platinum, gold, silver, copper, aluminum, zinc, nickel, titanium, and bismuth and alloys thereof can be preferably used.

  The auxiliary electrode can be installed either between the main electrode portion and the substrate, or on the surface of the main electrode portion opposite to the substrate. In any case, it is only necessary that the auxiliary electrode is electrically connected to the main electrode portion.

  There are no particular restrictions on the arrangement pattern of the auxiliary electrodes. It can be appropriately formed according to the required performance, such as linear, mesh, or circular. When the main electrode part is divided into a plurality of parts, the divided electrode parts may be connected to each other. However, in the case where the main electrode portion is a transparent electrode provided on the substrate on the display side, the auxiliary electrode is required to be provided with a shape and frequency that do not impair the visibility of the display element.

  As a method of forming the auxiliary electrode, a known method can be used. For example, patterning may be performed by photolithography, followed by printing, ink-jet printing, electrolytic plating or electroless plating, and exposure and development using a silver salt photosensitive material to form a pattern.

  The line width and line spacing of the auxiliary electrode pattern may be arbitrary values, but the line width needs to be increased in order to increase the conductivity. On the other hand, when an auxiliary electrode is attached to the transparent electrode, from the viewpoint of visibility, the area coverage of the auxiliary electrode viewed from the display element observation side is preferably 30% or less, and more preferably 10% or less.

  Thus, from the viewpoint of transmittance and conductivity, the line width of the auxiliary electrode is preferably 1 μm or more and 100 μm or less, and the line interval is preferably 50 μm to 1000 μm.

(Method of forming electrode)
A known method can be used to form the transparent electrode and the metal auxiliary electrode. For example, a method of depositing a mask on a substrate by a sputtering method or the like, a method of patterning by a photolithography method after forming the entire surface, and the like can be given.

  Electrodes can also be formed by electrolytic plating, electroless plating, printing methods, and ink jet methods.

  After forming an electrode pattern including a catalyst layer having a monomer polymerization ability on a substrate using an inkjet method, a monomer component that is polymerized by the catalyst and becomes a conductive polymer layer after polymerization is added, It is also possible to form a metal electrode pattern by polymerizing and further performing metal plating such as silver on the conductive polymer layer, and the process is greatly reduced because no photoresist or mask pattern is used. It can be simplified.

  When the electrode material is formed by a coating method, for example, a known method such as a dipping method, a spinner method, a spray method, a roll coater method, a flexographic printing method, a screen printing method, or the like can be used.

  Among the ink jet methods, the following electrostatic ink jet method is capable of continuously printing a highly viscous liquid with high accuracy and is preferably used for forming the transparent electrode and the metal auxiliary electrode of the present invention. The viscosity of the ink is preferably 30 mPa · s or more, and more preferably 100 mPa · s or more.

<Electrostatic inkjet method>
In the display element of the present invention, at least one of the transparent electrode of the composite electrode and the metal auxiliary electrode has a liquid discharge head having a nozzle with an internal diameter of 30 μm or less for discharging a charged liquid, and supplies a solution into the nozzle. It is one of the preferable embodiments that the liquid discharge device is provided with a supply unit that performs the discharge and a discharge voltage application unit that applies a discharge voltage to the solution in the nozzle. Further, it is preferable that the solution in the nozzle is formed by using a discharge device provided with a convex meniscus forming means for forming a state where the solution rises from the nozzle tip.

  In addition, it comprises operation control means for controlling application of drive voltage for driving the convex meniscus forming means and application of discharge voltage by the discharge voltage application means, and this operation control means applies application of the discharge voltage by the discharge voltage application means. It is also preferable to use a liquid ejection apparatus having a first ejection control unit that applies a driving voltage to the convex meniscus forming means when ejecting liquid droplets.

  In addition, an operation control unit that controls driving of the convex meniscus forming unit and voltage application by the discharge voltage applying unit is provided, and the operation control unit includes an operation for raising the solution by the convex meniscus forming unit, and application of the discharge voltage. A liquid discharge device having a second discharge control unit that synchronizes the liquid, and the operation control means includes a liquid level at the tip of the nozzle after the swell operation of the solution and the application of the discharge voltage. It is also a preferred form to use a liquid ejection apparatus having a liquid level stabilization control unit that performs operation control for drawing in the inside.

  By producing an electrode pattern using such an electrostatic inkjet, it is advantageous that an electrode having excellent on-demand characteristics, little waste material, and excellent dimensional accuracy can be obtained.

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

(Sealant)
The sealing agent is for sealing so as not to leak outside and is also called a sealing agent, and is an epoxy resin, urethane resin, acrylic resin, vinyl acetate resin, ene-thiol resin, silicone resin, Curing types such as a thermosetting type, a photo-curing type, a moisture-curing type, and an anaerobic curing type such as a modified polymer resin can be used.

(Columnar structure)
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.

(spacer)
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 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 merits 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, Case decoration of various equipment such as cash card, credit card, highway card, driver's license, hospital examination card, electronic medical record, health insurance card, basic resident register, passport, one-time password, electronic book, mobile phone cover, etc. Examples include a keyboard display, an electronic shelf label, an electronic POP, and an electronic advertisement. In particular, it is effective for manufacturing electronic books, electronic advertisements, electronic POPs, and the like that require display on a large screen.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

<< Production of display element >>
(Preparation of electrolyte)
(Preparation of electrolyte 1)
Electrolyte 1 was prepared by dissolving 0.025 parts by mass of tetrabutylammonium perchlorate in 2.5 parts by mass of dimethyl sulfoxide.

(Preparation of electrolyte 2)
Electrolyte 2 was prepared by dissolving 0.5 parts by mass of heptyl viologen and 0.0025 parts by mass of nitric acid in 2.5 parts by mass of 2-methoxyethanol.

(Preparation of electrolyte 3)
Electrolyte 3 was prepared by dissolving 0.1 part by mass of bismuth chloride, 0.2 part by mass of lithium bromide, and 0.025 part by mass of tetrabutylammonium perchlorate in 2.5 parts by mass of dimethyl sulfoxide.

(Preparation of electrolyte 4)
In 2.5 parts by mass of dimethyl sulfoxide, 0.025 parts by mass of spiro- (1,1 ′)-bipyrrolidinium tetrafluoroborate and carboxy TEMPO (4-carboxy-2,2,6,6-tetramethylpiperidine-1 -Oxyl free radical) 0.05 parts by mass and 0.1 parts by mass of silver p-toluenesulfonate were dissolved to prepare an electrolyte 4.

(Preparation of electrolyte 5)
In 2.5 parts by mass of dimethyl sulfoxide, 0.025 parts by mass of spiro- (1,1 ′)-bipyrrolidinium tetrafluoroborate and carboxy TEMPO (4-carboxy-2,2,6,6-tetramethylpiperidine-1 -Oxyl free radical) 0.05 parts by mass, 0.1 parts by mass of silver p-toluenesulfonate, and 0.2 parts by mass of 3-mercapto-1,2,4-triazole were dissolved to prepare an electrolyte 5.

(Preparation of electrolyte 6)
In 2.5 parts by mass of dimethyl sulfoxide, 0.025 parts by mass of tetrafluoroborate spiro- (1,1 ′)-bipyrrolidinium, carboxy TEMPO (4-carboxy-2,2,6,6-tetramethylpiperidine-1 -Oxyl free radical) 0.05 parts by mass, 0.1 parts by mass of silver p-toluenesulfonate, 0.2 parts by mass of 3,6-dithia-1,8-octanediol were dissolved to prepare an electrolyte 6. .

[Production of electrodes]
(Production of electrode 1)
An ITO (Indium Tin Oxide) film having a pitch of 145 μm and a width of 130 μm was formed as a conductive layer on a glass substrate having a thickness of 1.5 mm and a size of 2 cm × 4 cm according to a known method. .

(Preparation of electrode 2)
Hydrogen peroxide water was added to the tin (II) fluoride aqueous solution, and the deposited precipitate was collected and dried. In 10 parts by mass of a solution prepared by dissolving this dried precipitate in 55% hydrofluoric acid (0.1 mol / L) and an equal amount of an aqueous boric acid solution (0.2 mol / L). 1 part by weight of Baytron P (PEDOT (poly-3,4-ethylenedioxythiophene) -PSS (polystyrene sulfonic acid) aqueous dispersion, manufactured by HC Starck) was added and stirred to obtain a treatment. The electrode 1 was suspended vertically in the solution and immersed at room temperature for 30 minutes. After being pulled up, it was washed with pure water and dried in an atmosphere at 85 ° C. for 1 hour to produce an electrode 2.

(Preparation of electrode 3)
On the electrode 1, the following titanium dioxide dispersion was screen-printed so that the average film thickness after drying was 20 μm, then dried at 50 ° C. for 30 minutes to evaporate the solvent, and then in an atmosphere at 85 ° C. Electrode 3 having a porous white scattering layer formed by drying for 1 hour was produced.

<Preparation of titanium dioxide dispersion>
After adding Kuraraypoval PVA235 (made by Kuraray Co., Ltd., polyvinyl alcohol resin) to a water / ethanol mixed solution so as to have a solid content concentration of 2% by mass and dissolving by heating, titanium dioxide CR-90 (made by Ishihara Sangyo Co., Ltd.) ) Was dispersed with an ultrasonic disperser so as to be 20% by mass to obtain a titanium dioxide dispersion.

(Preparation of electrode 4)
1 part by weight of Baytron P (supra) is added to 10 parts by weight of a mixed solution of an ammonium fluoride titanate aqueous solution (0.1 mol / L) and an aqueous boric acid solution (0.2 mol / L) and stirred. The electrode 1 was suspended vertically in the treatment solution thus obtained and immersed at room temperature for 30 minutes. After being pulled up, it was washed with pure water and dried in an atmosphere at 85 ° C. for 1 hour to produce an electrode 4.

(Preparation of electrode 5)
1 part by weight of Baytron P (supra) was added and stirred in 10 parts by weight of a mixed solution of ammonium silicofluoride aqueous solution (0.1 mol / L) and boric acid aqueous solution (0.2 mol / L). The electrode 1 was suspended vertically in the obtained treatment liquid and immersed at room temperature for 30 minutes. After being pulled up, it was washed with pure water and dried in an atmosphere at 85 ° C. for 1 hour to produce an electrode 5.

(Preparation of electrode 6)
Disperse polyvinyl ferrocene in a 3% by weight aqueous sodium dodecylbenzenesulfonate solution in 10 parts by weight of a mixed solution of ammonium fluoride titanate aqueous solution (0.1 mol / L) and boric acid aqueous solution (0.2 mol / L). The electrode 1 was suspended vertically in a treatment liquid obtained by adding and stirring 1 part by mass of the dispersion, and immersed for 30 minutes at room temperature. After being pulled up, it was washed with pure water and dried in an atmosphere at 85 ° C. for 1 hour. Furthermore, the titanium dioxide dispersion used in the production of the electrode 3 was screen-printed so that the average film thickness after drying was 20 μm, then dried at 50 ° C. for 30 minutes to evaporate the solvent, and then the 85 ° C. The electrode 6 was produced by drying in an atmosphere for 1 hour.

(Preparation of electrode 7)
On the electrode 1, Baytron P (supra) is spin-coated so that the average film thickness after drying is 0.3 μm, then dried at 50 ° C. for 30 minutes, and then dried in an atmosphere at 85 ° C. for 1 hour. Thus, an electrode 7 was produced.

(Preparation of electrode 8)
On electrode 1, a tetrahydrofuran solution of polyvinyl ferrocene was spin-coated so that the average film thickness after drying was 0.3 μm, and then dried in an atmosphere at 85 ° C. for 1 hour to prepare electrode 8.

[Production of display element]
(Preparation of display element 1)
After the periphery of the electrode 3 is edged with an olefin-based sealant containing glass spherical beads having an average particle size of 40 μm as a volume fraction of 10%, the striped electrodes are orthogonal to the electrodes 3 and 2 respectively. The cells were bonded together and further heated and pressed to produce an empty cell. The electrolytic solution 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.

(Production of display elements 2 to 11)
In the production of the display element 1, the display elements 2 to 11 were similarly manufactured except that the types of the display side electrode and the non-display side electrode constituting the counter electrode and the type of the electrolyte were changed to the combinations shown in Table 1. Produced.

<< Evaluation of display element >>
[Evaluation of durability]
(Evaluation of display elements 1 to 5)
About display elements 1-5, durability was evaluated as follows.

Connect both electrodes of each display element to both terminals of the constant voltage power supply, apply a voltage of +1.5 V to the display-side electrode for 1.5 seconds, and then reflect the reflectance of the display part of each display element to Konica Minolta Sensing The measurement was performed with a spectrocolorimeter CM-3700d manufactured by the company. The reflectance at the maximum absorption wavelength in the visible light region (wavelength 400 nm to 700 nm) at that time was defined as R _{1 (0)} .

Thereafter, a voltage of 10,000 cycles was applied to each display element with +1.5 V 0.5 seconds and -1.5 V 0.5 seconds as one cycle, and then measured in the same manner as described above. _{1 (10000)} .

The change in the contrast ratio before and after the repetitive voltage application was defined as ΔR ₁ = | R _{1 (0)} −R _{1 (10000)} |, which was used as an index of the stability of the reflectance when repeatedly driven. Here, as the value of [Delta] R ₁ is small, so that the excellent stability of the reflectance when obtained by repeatedly driving.

(Evaluation of display elements 6 to 11)
About display elements 6-11, durability was evaluated as follows.

Connect both electrodes of each display element to both terminals of the constant voltage power supply, apply a voltage of -1.5 V to the display-side electrode for 1.5 seconds, and then change the reflectance of the display portion of each display element to Konica Minolta Measurement was performed with a spectral colorimeter CM-3700d manufactured by Sensing Corporation. The reflectance at a wavelength of 550 nm was R _{2 (0)} .

Thereafter, a voltage of 10,000 cycles is applied to each display element with +1.5 V 0.5 seconds and -1.5 V 0.5 seconds as one cycle, and then measured in the same manner as described above. _{2 (10000)} .

The change in contrast ratio before and after the repetitive voltage application was defined as ΔR ₂ = | R _{2 (0)} −R _{2 (10000)} | Here, the smaller the value of ΔR _2, the better the stability of the reflectance when it is repeatedly driven.

  Table 1 shows the configuration of each display element and the obtained durability evaluation results.

  As is apparent from the results shown in Table 1, the display element produced by the method defined in the present invention has good reflectance stability when it is repeatedly driven and excellent durability compared to the comparative example. I understand that

Claims (7)

An electrolyte and a redox active substance layer are provided between a pair of counter electrodes, and the redox active substance layer includes at least 1) a redox active polymer, 2) a metal ion or a nonmetal ion, and 3) a coordination. A display element, wherein the counter element is formed by immersing at least one electrode of the counter electrode in a treatment liquid containing a substrate and 4) a deposition accelerator. The display element according to claim 1, wherein the redox active material layer is formed on a non-display side electrode. The display element according to claim 1, wherein the electrolyte contains a metal salt compound, and performs black display and white display by a driving operation of the counter electrode. The display element according to claim 3, wherein the metal salt compound is a silver salt compound. The display element according to any one of claims 1 to 4, wherein the electrolyte contains a compound represented by the following general formula (G-1) or (G-2).
General formula (G-1)
_{Rg 11} -S-Rg _{12
Wherein, Rg 11,} Rg ₁₂ each represents a substituted or unsubstituted hydrocarbon group. Further, these hydrocarbon groups may contain one or more nitrogen atom, oxygen atom, phosphorus atom, sulfur atom or halogen atom, and Rg ₁₁ and Rg ₁₂ may be connected to each other to take a cyclic structure. ]

[Wherein, 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, and Rg ₂₁ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkylcarbonamide group, an arylcarbonamide group, an alkylsulfonamide group, an arylsulfonamide group, an alkoxy group, an aryl Oxy group, alkylthio group, arylthio group, alkylcarbamoyl group, arylcarbamoyl group, carbamoyl group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylsulfonyl group, alkoxycarbonyl group, Represents an aryloxycarbonyl group, an alkylcarbonyl group, an arylcarbonyl group, an acyloxy group, a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, Of Rg ₂₁ may be the same or different, and may be linked to each other to form a condensed ring. ] The display element according to claim 1, wherein the redox active material layer contains SiO ₂ or TiO _2. It is a manufacturing method of a display element given in any 1 paragraph of Claims 1-6,
A redox-active polymer; a complex formed from a metal ion or non-metal ion and a ligand; and a deposition accelerator that reacts with the ligand of the complex to precipitate a metal or non-metal oxide from the solution. A step of preparing a treatment liquid containing:
Immersing a substrate having an electrode in the treatment liquid to form a redox active substance layer on the electrode;
Using the substrate on which the redox active material layer is formed as at least one electrode and holding the redox active material layer and the electrolyte between a pair of opposed electrodes to produce a display element. A method for manufacturing a display element.