JP2010134226A - Display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display element having excellent memory properties, durability and high contrast of white and black with a simple member construction. <P>SOLUTION: In the display element which has an electrolyte and a white scattering matter between counter electrodes and wherein a polymer compound whose main chain includes two or more kinds of units is fixed to at least one of the electrodes, the polymer compound is oxidized and reduced by applying voltage between the counter electrodes to perform reversible coloration and decoloration. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrochemical display element using a novel electrode for an electrochemical display element.

  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 increasing more and more.

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

  As a display means to compensate for these drawbacks, a reflection type display using so-called "memory" that uses external light and does not consume power for image retention is known. However, it has sufficient performance for the following reasons. It is hard to say that it has.

  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 3V or less, 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 a simple cell. There are advantages such as excellent configuration, black-white contrast and black quality.

  Problems with the ED method include low power generation efficiency when metal ions are reduced to metal (absorbance change rate per quantity of electricity), and power consumption increases, and electrochemical reactions that precipitate and dissolve metals. There was a problem that the decoloration speed could not be increased due to the slowness.

  On the other hand, an EC method using an organic material having a higher coloring efficiency than metal ions as a decoloring agent has been widely studied. Among them, a specific bipyridinium compound (also called a viologen compound) is widely used. ing.

  However, most of the conventionally known bipyridinium compounds have a blue to purple or green color, and it has been difficult to perform black display.

  On the other hand, there is an example in which a bipyridinium compound is used to enable black reversible color development (see, for example, Patent Document 1). Specifically, 1,1′-di-n-heptyl-4,4′-bipyridinium dibromide capable of blue to magenta color development and 1- (4-cyanophenyl)-capable of green color development. It is described that a black reversible color can be developed by combining with 1'-heptyl-4,4'-bipyridinium bromide chloride.

  However, the method of performing black color development with two types of EC dyes is difficult to absorb the wavelength in the entire visible light range, and three types of ECs of yellow, magenta, and cyan are required for clearer black display. It is preferable to use a dye. In Patent Document 1, black color is generated in a solution and is not intended to be immobilized on an electrode. In order to improve the vivid black color development and the memory property, it is necessary to fix the EC dye on the electrode so that it does not flow out on the electrolyte.

In recent years, bipyridinium compounds that perform reversible color development of yellow, magenta, and cyan have been reported as dyes that can contribute to full-color image formation (see, for example, Patent Documents 2 to 4). However, these methods do not suggest reversible black display.
JP 2008-96786 A JP 2007-219272 A JP 2007-171781 A JP 2008-20519 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 having a simple member configuration, excellent memory properties and durability, and high white and black contrast.

  As a result of studying reversible black display of a polymer compound in combination with a bipyridinium compound that performs reversible color development of yellow, magenta, and cyan, the present inventor has achieved a memory property and durability with a simple member configuration. It has been found that a display device that is excellent and has a high contrast between white and black is possible.

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

  1. A polymer having an electrolyte and a white scatterer between counter electrodes, and at least one of the repeating units represented by the following general formulas (1) to (3) in the main chain in at least one counter electrode A display element, wherein a compound is immobilized, and reversible color development is performed by oxidizing and reducing the polymer compound by applying a voltage between the counter electrodes.

(Wherein, a, b are integers that satisfy a × b = 2, .Y X b- is representing the appropriate b-valent anion, M, C by electrochemical redox reaction, reversible A bipyridinium compound that performs reversible color development, Y is yellow, M is magenta, and C is cyan, and L _{1 to} L ₃ are divalent linking groups, (Indicates an aliphatic hydrocarbon or an aromatic hydrocarbon that may have a substituent.)
2. In the general formula (1), Y is any one of the following general formulas (4) to (8), and in the general formula (2), M is any of the following general formulas (9) to (11). 2. The display element according to 1 above, wherein in the general formula (3), C is any one of the following general formulas (12) to (16).

(In the formula, A _{1 to} A ₈ and Z _{1 to} Z ₄ represent a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, or a halogen group.
At least two of B _{1 to} B ₄ are a trifluoromethyl group or a cyano group, and other B _{1 to} B ₄ are a hydrogen atom or an aliphatic hydrocarbon group which may be substituted. Become.
E represents one of S, O, and N-R. However, R represents either a hydrogen atom, an aliphatic hydrocarbon group which may be substituted, or an aromatic hydrocarbon group which may be substituted. )
3. 3. The display element according to 1 or 2 above, wherein the polymer compound contains all repeating units represented by the general formulas (1) to (3) in the main chain.

  4). 4. The display element according to any one of 1 to 3, wherein the polymer compound has a molecular weight of 3000 or more and 50000 or less.

5). The polymer compound has a —COOH, —P═O (OH) ₂ , —OP═O (OH) ₂ , —NCO or —Si (OR) ₃ (R represents an alkyl group) group. 5. The display element according to any one of 1 to 4 above, wherein

  6). 6. The display element according to any one of 1 to 5, wherein the electrolyte composition contains a silver salt compound that dissolves and precipitates by an electrochemical redox reaction.

  According to the present invention, it has been possible to provide a display element having a simple member configuration, excellent memory performance and durability, and high white and black contrast.

  As a result of intensive studies in view of the above problems, the inventor has at least two of the repeating units represented by the general formulas (1) to (3) as a main chain in at least one counter electrode. The display element is characterized in that the polymer compound is fixed, and reversible color development is achieved by applying a voltage between the counter electrodes to oxidize and reduce the polymer compound. As a result, the present inventors have found that a display device having excellent memory properties and durability and high white and black contrast can be realized with a simple member configuration.

  Details of the present invention will be described below.

[Basic structure of display element]
In the display element of the present invention, the display portion is provided with one corresponding counter electrode. Porous electrode such as a transparent electrode and the TiO ₂ electrode such as ITO electrodes to the electrode 1, one of the opposing electrode closer to the display unit, the conductive electrode is provided on the other electrode 2. Between the electrode 1 and the electrode 2, the electrolyte according to the present invention and a white scatterer are contained, and the polymer compound according to the present invention is immobilized on the electrode 1, and a positive and negative voltage is applied between the counter electrodes. By applying, the polymer compound can be reversibly switched between white display and black display by oxidizing and reducing the polymer compound.

  If necessary, the electrolyte composition contains a metal salt compound that dissolves and precipitates by an electrochemical oxidation-reduction reaction, so that both the polymer compound and the metal salt compound display white. And black display may be reversibly switched.

  Hereinafter, the components will be sequentially described.

[Polymer compound]
The polymer compound applied in the present invention is a copolymer containing at least two or more of repeating units represented by the general formulas (1) to (3) in the main chain.

In the general formulas (1) to (3), a and b are integers satisfying a × b = 2, and X ^b− represents an appropriate b-valent anion.

X ^b− represents an inorganic acid such as F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , IO ₄ ⁻ , PF ₆ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , phosphate ion, and SCN ^−. Ions, or organic acid ions such as benzenesulfonate ion, p-toluenesulfonate ion, alkylsulfonate ion, trihaloalkylsulfonate ion, benzenecarboxylate ion, alkylcarboxylate ion, and trihaloalkylcarboxylate ion Shall.

  Y is a wavelength range of 400 to 500 nm, M is a wavelength range of 500 to 600 nm, and C is a wavelength range of 600 to 700 nm, each of which is a bipyridinium compound having maximum absorption during reduction color development. However, the above-mentioned wavelength is the maximum absorption wavelength in the visible light region, and excludes absorption in the ultraviolet region and infrared region.

  The following are general formulas (4) to (8) as examples of Y that can be used in the general formula (1), and general formulas (9) are examples of M that can be used in the general formula (2). The general formulas (12) to (16) are shown as examples of C that can be used in the general formula (3), but are not limited thereto.

In the general formulas (4) to (16), A _{1 to} A ₈ and Z _{1 to} Z ₄ represent a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, or a halogen group.

At least two of B _{1 to} B ₄ are a trifluoromethyl group or a cyano group, and other B _{1 to} B ₄ are a hydrogen atom or an aliphatic hydrocarbon group which may be substituted. Become. E represents one of S, O, and N-R. However, R represents either a hydrogen atom, an aliphatic hydrocarbon group which may be substituted, or an aromatic hydrocarbon group which may be substituted.

Furthermore, although the specific example of the said General formula (4)-(16) is shown below, it is not limited to these.
Bipyridinium compound (Y)

Bipyridinium compounds (M)

Bipyridinium compound (C)

Furthermore, L < ₁ > -L < ₃ > is a bivalent coupling group. L _{1 to} L ₃ may be the same as or different from each other. L _{1 to} L ₃ may contain any atom of oxygen, nitrogen, sulfur, silicon, phosphorus, boron, and halogen. Further, L ₁ ~L ₃ is to firmly immobilized on the electrode, it is particularly preferred to have an adsorption group or reactive group to the electrode surface. The adsorptive _{group, -COOH, -P-O (OH} ) 2, -OP = O (OH) 2 and the like, is -NCO and -Si _(OR) 3 (R is a reactive group, an alkyl group For example).

Specific examples of L _{1 to} L _{3 that} can be used in the polymer compound of the present invention are shown below, but are not limited thereto.

  In order to perform clear black color development, the polymer compound applied in the present invention is a copolymer containing all the repeating units represented by the general formulas (1) to (3) in the main chain. Is preferred.

  In order to perform clear black color development and improve memory properties, it is necessary to immobilize the electrochromic dye on the electrode. The polymer compound of the present invention preferably has an overall molecular weight of 3000 or more. . Another advantage of polymerizing is that the film thickness can be controlled and formed so that a desired dye amount can be easily set. On the other hand, if the degree of polymerization is too high, the solubility in a solvent is lowered, which causes a problem in electrode production. Therefore, it is preferable to set the total molecular weight to about 50,000 or less.

  In general, techniques for supporting a polymer compound on a porous electrode include coating methods such as electrolytic polymerization, electrolytic deposition, dip, spin, and cast, but more preferably supported via a chemical bond. It is a method, can be firmly fixed to the electrode, and excellent durability can be obtained as compared with other methods.

  Although the specific example of the polymer compound represented by General formula (1) which can be used by this invention is shown in Table 1, it is not limited to these.

[Organic solvent]
An organic solvent may be used in combination with the electrolyte according to the present invention. The organic solvent preferably has a boiling point in the range of 120 to 300 ° C., for example, propylene carbonate, ethylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, butylene carbonate, γ-butyl lactone, sulfolane, dimethyl sulfoxide, butyronitrile. , Propionitrile, acetonitrile, acetylacetone, 4-methyl-2-pentanone, 2-butanol, 1-butanol, 2-propanol, 1-propanol, acetic anhydride, ethyl acetate, ethyl propionate, dimethoxyethane, diethoxyfuran, Tetrahydrofuran, ethylene glycol, diethylene glycol, triethylene glycol monobutyl ether, tricresyl phosphate, 2 ethylhexyl phosphate Dioctyl phthalate, and di-octyl sebacate and the like.

〔Electrolytes〕
As the supporting electrolyte that can be used in the electrolyte composition 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, the compound shown below 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 - 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 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.

[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. It is a generic term, and there are no particular limitations on the state species of the phase 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 (hereinafter also referred to as Metal) contained in the electrolyte according to the present invention is preferably 0.2 mol / kg ≦ [Metal] ≦ 2.0 mol / kg. If the metal ion concentration is 0.2 mol / kg or more, a silver solution having a sufficient concentration can be obtained, and a desired driving speed can be obtained. If the metal ion concentration is 2 mol / kg or less, precipitation is prevented, and storage at low temperature is possible. The stability of the electrolyte solution is improved.

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

Formula (1): 0 ≦ [X] / [Metal] ≦ 0.1
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 larger 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 compound]
In the present invention, a silver salt solvent can be used to promote dissolution and precipitation of the silver salt. The silver salt solvent may be any compound that can solubilize silver in the electrolyte. For example, solubilize silver or a compound containing silver by coexisting with a compound containing a chemical structural species that interacts with silver, such as a coordinate bond with silver or a weak supply bond with silver. It is common to use a means for converting to an object. As the chemical species, 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 particular, it is preferable to contain at least one 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)]
General formula (G-1)
_{Rg 11} -S-Rg ₁₂
[Wherein Rg ₁₁ and Rg ₁₂ each represents 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. ]

[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, Rg ₂₁ represents a substituent, and when n is 2 or more, each Rg ₂₁ may be the same or different, and may be connected to each other to form a condensed ring. It may be formed. ]
In the general formula (G-1), Rg ₁₁ and Rg ₁₂ each represent a substituted or unsubstituted hydrocarbon group, which includes an aromatic straight chain group or a branched group. Further, these hydrocarbon groups may contain one or more nitrogen atoms, oxygen atoms, phosphorus atoms, and sulfur atoms, and Rg ₁₁ and Rg ₁₂ may be connected to each other to take a cyclic structure. However, when a ring containing an S atom is formed, an aromatic group is not taken.

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

  Hereinafter, although the specific example of a compound represented by general formula (G-1) which concerns on this invention is shown, in this invention, it is not limited only to these illustrated compounds.

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

  Among the above-exemplified compounds, the exemplified compound G1-3 is particularly preferable from the viewpoint that the object and effects of the present invention can be exhibited.

  Next, the compound represented by formula (G-2) according to the present invention will be described.

In the general formula (G-2), M represents a hydrogen atom, a metal atom, or quaternary ammonium. Z represents a nitrogen-containing heterocyclic ring excluding imidazole rings. n represents an integer of 0 to 5, Rg ₂₁ represents a substituent, and when n is 2 or more, each Rg ₂₁ may be the same or different, and may be connected to each other to form a condensed ring. It may be formed.

Examples of the metal atom represented by M in the general formula (G-2) include Li, Na, K, Mg, Ca, Zn, and Ag. Examples of the quaternary ammonium include NH ₄ , N (CH ₃ ) ₄ , N (C ₄ H ₉ ) ₄ , N (CH ₃ ) ₃ C ₁₂ H ₂₅ , N (CH ₃ ) ₃ C ₁₆ H ₃₃ , N (CH ₃ ) ₃ CH ₂ C ₆ H ₅ Etc.

  Examples of the nitrogen-containing heterocycle having Z as a constituent in the general formula (G-2) include, for example, a tetrazole ring, a triazole ring, an imidazole ring, an oxadiazole ring, a thiadiazole ring, an indole ring, an oxazole ring, and a benzoxazole ring. Benzimidazole ring, benzothiazole ring, benzoselenazole ring, naphthoxazole ring and the like.

The substituents represented by Rg ₂₁ of the general formula (G-2), not particularly limited, but, for example, a hydrogen atom, a halogen atom (e.g., fluorine atom, chlorine atom, bromine atom, an iodine atom), alkyl Groups (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.), aryl Rusulfonamide group (for example, benzenesulfonylamino group, toluenesulfonylamino group, etc.), alkoxy group, aryloxy group (for example, phenoxy etc.), alkylthio group (for example, methylthio, ethylthio, butylthio etc.), arylthio group (for example, Phenylthio group, tolylthio group, etc.), alkylcarbamoyl group (for example, methylcarbamoyl, dimethylcarbamoyl, ethylcarbamoyl, diethylcarbamoyl, dibutylcarbamoyl, piperidylcarbamoyl, morpholylcarbamoyl, etc.), arylcarbamoyl group (for example, phenylcarbamoyl, methylphenylcarbamoyl, Ethylphenylcarbamoyl, benzylphenylcarbamoyl, etc.), carbamoyl group, alkylsulfamoyl group (eg, methylsulfamoyl) Dimethylsulfamoyl, ethylsulfamoyl, diethylsulfamoyl, dibutylsulfamoyl, piperidylsulfamoyl, morpholylsulfamoyl, etc.), arylsulfamoyl groups (eg phenylsulfamoyl, methylphenylsulfamoyl) Famoyl, ethylphenylsulfamoyl, benzylphenylsulfamoyl, etc.), sulfamoyl group, cyano group, alkylsulfonyl group (eg, methanesulfonyl group, ethanesulfonyl group, etc.), arylsulfonyl group (eg, phenylsulfonyl, 4- Chlorophenylsulfonyl, p-toluenesulfonyl, etc.), alkoxycarbonyl groups (for example, methoxycarbonyl, ethoxycarbonyl, butoxycarbonyl, etc.), aryloxycarbonyl groups (for example, phenoxycarbonyl) Etc.), alkylcarbonyl groups (eg acetyl, propionyl, butyroyl etc.), arylcarbonyl groups (eg benzoyl group, alkylbenzoyl groups etc.), acyloxy groups (eg acetyloxy, propionyloxy, butyroyloxy etc.), carboxyl groups, Carbonyl group, sulfonyl group, amino group, hydroxy group or heterocyclic group (for example, oxazole ring, thiazole ring, triazole ring, selenazole ring, tetrazole ring, oxadiazole ring, thiadiazole ring, thiazine ring, triazine ring, benzoxazole ring Benzthiazole ring, indolenine ring, benzselenazole ring, naphthothiazole ring, triazaindolizine ring, diazaindolizine ring, tetraazaindolizine ring group, etc.). These substituents further include those having a substituent.

  Next, although the preferable specific example of a compound represented by general formula (G-2) is shown, this invention is not limited to these compounds.

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

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

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

  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 of the vinyl monomer having a (e.g., sodium methacrylate, Copolymers with ammonium acid, 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 an aqueous solvent include latexes such as natural rubber latex, styrene butadiene rubber, butadiene rubber, nitrile rubber, chloroprene rubber, isoprene rubber, polyisocyanate, epoxy, acrylic, silicon, 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.

[Solid electrolyte, gel electrolyte]
The electrolyte according to the present invention is not only a solution electrolyte composed of a solvent or an ionic liquid, but also a high-viscosity electrolyte or a gel electrolyte (hereinafter, referred to as a solid electrolyte or a polymer compound containing substantially no solvent). Gel electrolyte) can be used.

  Examples of the solid electrolyte and gel electrolyte applicable to the present invention include a solid electrolyte described in JP-A No. 2002-341387, a polymer solid electrolyte described in JP-A No. 2002-341387, and JP-A No. 2004-20928. A solid polymer electrolyte described in JP-A No. 2004-191945, a solid polymer electrolyte described in JP-A No. 2005-338204, and a polymer described in JP-A No. 2006-323022 Examples thereof include solid electrolytes, solid electrolytes described in JP-A No. 2007-141658, solid electrolytes described in JP-A No. 2007-163865, and gel electrolytes.

[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 polymerization degree 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 layer. .

〔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, silicon 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〕
(Display side transparent electrode)
Of the counter electrodes, the electrode positioned on the display side is preferably 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, Platinum, Gold, Silver, Rhodium, Copper, Examples thereof include chromium, carbon, aluminum, silicon, amorphous silicon, and BSO (Bismuth Silicon Oxide).

  In addition, polythiophene, polypyrrole, polyaniline, polyacetylene, polyparaphenylene, polyselenophenylene, etc., and their modifying compounds can be used alone or in combination.

  As an electrode located on the display side, Indium Tin Oxide (ITO: Indium Tin Oxide), Indium Zinc Oxide (IZO: Indium Zinc Oxide), Fluorine Doped Tin Oxide (FTO), Indium Oxide, Zinc Oxide, etc. An electrode made of a transparent conductive oxide is preferable.

  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.

(Transparent porous electrode)
As one embodiment of the transparent electrode, a nanoporous electrode having a nanoporous structure can be provided on the transparent electrode. This nanoporous electrode is substantially transparent when a display element is formed, and can carry an electroactive substance such as an electrochromic dye.

  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.

  As a method for forming such a nanoporous electrode, a dispersion containing fine particles constituting the nanoporous electrode is formed in layers by an ink jet method, a screen printing method, a blade coating method, etc., and then heated at a predetermined temperature. A method of making porous by drying, baking, a method of making nanoporous by anodizing or photoelectrochemical etching after forming an electrode layer by sputtering, CVD, atmospheric pressure plasma, etc. Is mentioned. Also, the sol-gel method, Adv. Mater. It can also be formed by the method described in 2006, 18, 2980-2983.

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.

  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.

  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.

(Counter electrode)
The counter electrode can be used without particular limitation as long as it conducts electricity.

  As the constituent material of the counter electrode, in addition to the same material as the transparent electrode, metals such as platinum, gold, silver, copper, aluminum, zinc, nickel, titanium, bismuth and their alloys, carbon, etc. have no transparency. A material can also be preferably used.

  Further, as described in the section of the display-side transparent electrode, a nanoporous electrode having a nanoporous structure can be provided on the counter electrode.

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. Particularly preferred is ITO.

  As the counter electrode of the present invention, an electrode provided with a nanoporous TiO2 electrode or a nanoporous ITO electrode on an ITO electrode is preferable, and an electrode provided with a nanoporous ITO electrode is particularly preferable.

(Porous carbon electrode)
In the present invention, a porous carbon electrode can also be used. Porous carbon electrodes that can be adsorbed and supported include graphite, non-graphitizable carbon, graphitizable carbon, composite carbon, and carbon compounds obtained by doping carbon with boron, nitrogen, phosphorus, etc. Can be mentioned. Examples of the shape of the carbon particles include mesophase microspheres and fibrous graphite. Mesophase spherules can be obtained by firing coal tar pitch or the like at 350 to 500 ° C., and further classifying these spherules and graphitizing by high-temperature firing can provide a good porous carbon electrode. In addition, fibrous graphite can be obtained from pitch-based, PAN-based, and vapor-grown fibers.

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

  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, a patterning method by photolithography, a printing method, an ink jet method, electrolytic plating or electroless plating, or a method of forming a pattern by exposing and developing using a silver salt photosensitive material may be used.

  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.

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

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

  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.

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

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

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

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

[Display element driving method]
The 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, Cash cards, credit cards, highway cards, driver's licenses, hospital examination cards, electronic medical records, health insurance cards, Basic Resident Registers, passports, electronic books, etc.

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

<< Production of display element >>
(Preparation of electrolyte)
(Preparation of electrolyte 1)
In 2.5 g of γ-butyrolactone, 0.025 g of p-toluenesulfonic acid spiro- (1,1 ′)-bipyrrolidinium and 0.002 g of ferrocene were dissolved to obtain an electrolytic solution 1.

(Preparation of electrolyte 2)
In 2.5 g of γ-butyrolactone, 0.1 g of silver p-toluenesulfonate, 0.2 g of compound (G1-3), 0.025 g of p-toluenesulfonic acid spiro- (1,1 ′)-bipyrrolidinium, ferrocene 0 0.002 g was dissolved to obtain an electrolytic solution 2.

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

  Next, after applying titanium dioxide having a thickness of 50 μm to the transparent electrode, drying treatment was performed at 150 ° C. for 12 minutes in an electric furnace, and further, baking was performed at 450 ° C. for 50 minutes to obtain an electrode 1.

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

  Next, the periphery was trimmed with an olefin-based sealant containing 10% glass spherical bead spacers having an average particle size of 40 μm, and then polyvinyl alcohol (average polymerization degree 3500, saponification degree 87%). ) 20% of titanium dioxide CR-90 manufactured by Ishihara Sangyo Co., Ltd. was added to an isopropanol solution containing 2%, and the mixed solution dispersed with an ultrasonic disperser was applied so that the thickness after drying was 20 μm. Thereafter, the film was dried at 85 ° C. for 30 minutes to evaporate the solvent, and then dried in an atmosphere at 45 ° C. for 1 hour to obtain an electrode 2.

(Preparation of electrode 3)
A 20 mM aqueous solution of the polymer compound (P-1) shown in Table 1 was prepared, applied on the electrode 1 by a spin coating method, washed and dried to obtain an electrode 3.

(Preparation of electrode 4)
The electrode 1 was immersed in a 20 mM aqueous solution of the polymer compound (P-2) shown in Table 1 above at room temperature for 16 hours, then washed with water and dried to obtain an electrode 4.

(Preparation of electrode 5)
An electrode 5 was obtained in the same manner as the electrode 3 except that the polymer compound P-1 was changed to the monomer compound shown below.

[Production of display element]
Example 1 Production of Display Element 1
The electrode 2 and the electrode 3 were bonded together and 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.

(Example 2: Production of display element 2)
A display element 2 was produced in the same manner as in Example 1 except that the electrode 3 was changed to the electrode 4.

(Production of display elements 3 to 8)
Display elements 3 to 8 were produced from electrodes produced using the polymer compounds shown in Table 1.

(Comparative Example 1: Production of display element 9)
A display element 9 was produced in the same manner as in Example 1 except that the electrode 3 was changed to the electrode 5.

(Comparative Example 2: Production of display element 10)
A display element 10 was produced in the same manner as in Example 3 except that the electrode 3 was changed to the electrode 1.

<< Evaluation of display element >>
[Evaluation of coloring and memory properties]
Both electrodes of the display elements 1 to 5 were connected to both terminals of the constant voltage power source, and a constant voltage of −1.5 V was applied. Immediately after coloring the display element and 1 minute later, the reflectance of 400 to 750 nm was measured with a spectrocolorimeter CM-3700d manufactured by Konica Minolta Sensing Co., Ltd., and the coloring and memory properties were evaluated. Here, the smaller the obtained reflectance value is in the entire visible light region, the higher the ability to express black.

  The evaluation results of color development / memory properties obtained as described above are shown in FIGS.

  As shown in FIG. 1, the display element 1 (Invention 1) absorbs the wavelength in the entire visible light region immediately after color development and 1 minute later, and can display a clear black.

  On the other hand, as shown in FIG. 2, the display element 9 (Comparative Example 1) does not sufficiently absorb the wavelength in the visible light region immediately after the color development, and almost no absorption occurs after 1 minute.・ The memory performance was low.

  This is because the dye is a low molecular weight compound, so that it is not sufficiently adsorbed at the time of electrode preparation and diffused into the electrolyte at the time of measurement.

[Durability evaluation]
In the same manner as described above, a constant voltage of -1.5 V is applied to both electrodes of the display elements 1 to 3 and 5 as a coloring process for 1.5 seconds and +0.5 V is applied as a decoloring process for 1.5 seconds. The voltage was continuously applied alternately. The number of color development and decoloration while white reflectance / black reflectance ≧ 10 at a wavelength of 550 nm was defined as durability and evaluated. The results are shown in Table 2.

  Compared to the comparative example, the display element 1 (Invention 1) can repeat the color development about 2000 times, and the display element 2 (Invention 2) develops the color in the same manner as in the initial state even if it is repeated 10,000 times. Continued. This is because desorption from the electrode could be suppressed by introducing the adsorbing group.

[Evaluation of color development speed]
In the same manner as described above, a constant voltage of -1.5 V was applied to both electrodes of the display elements 1 to 10 for 3 seconds. Every 0.1 second, the reflectance at a wavelength of 550 nm was measured with a spectrocolorimeter CM-3700d manufactured by Konica Minolta Sensing.

  The time until the white reflectance / black reflectance ≧ 10 at a wavelength of 550 nm was defined as the color development rate and evaluated. The results are shown in Table 2. In the display elements 1 to 8 (present inventions 1 to 8), the color development speed was within 1 second, which was a sufficiently good speed for practical use. In particular, the display element 3 (present invention 3) was the fastest at 0.4 seconds. This is because both the polymer compound of the present invention and the silver salt compound contributed to black color development. On the other hand, in the display element 10 (Comparative Example 2), the color development speed was 1.4 seconds, which was slightly slower.

[Evaluation of coloring efficiency]
In the same manner as described above, a constant voltage of -1.5 V was applied to the display-side electrodes of the display elements 1 to 10, and the amount of electricity consumed was measured. The amount of electricity consumed per unit area required to reach white reflectance / black reflectance ≧ 10 at a wavelength of 550 nm was defined as color development efficiency and evaluated. The results are shown in Table 2. In display elements 1 to 8 (present inventions 1 to 8), the value was 4.3 mC / cm ² or less, which was a relatively good result. On the other hand, in the display element 10 (Comparative Example 2), it was 7.8 mC / cm ² , resulting in poor color development efficiency.

It is a figure of color development and memory performance evaluation. It is a figure of color development and memory performance evaluation.

Explanation of symbols

1 Measurement plot before charge application 2 Measurement plot immediately after charge application 3 Measurement plot 1 minute after charge application

Claims (6)

A polymer having an electrolyte and a white scatterer between counter electrodes, and at least one of the repeating units represented by the following general formulas (1) to (3) in the main chain in at least one counter electrode A display element, wherein a compound is immobilized, and reversible color development is performed by oxidizing and reducing the polymer compound by applying a voltage between the counter electrodes.

(Wherein a and b are integers satisfying a × b = 2, and X ^b− represents an appropriate b-valent anion. Y, M and C are reversible by an electrochemical redox reaction. A bipyridinium compound that performs reversible color development, Y is yellow, M is magenta, and C is cyan, and L _{1 to} L ₃ are divalent linking groups, (Indicates an aliphatic hydrocarbon or an aromatic hydrocarbon that may have a substituent.) In the general formula (1), Y is any one of the following general formulas (4) to (8), and in the general formula (2), M is any of the following general formulas (9) to (11). 2. The display element according to claim 1, wherein C is any one of the following general formulas (12) to (16) in the general formula (3):

(In the formula, A _{1 to} A ₈ and Z _{1 to} Z ₄ represent a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, or a halogen group.
At least two of B _{1 to} B ₄ are a trifluoromethyl group or a cyano group, and other B _{1 to} B ₄ are a hydrogen atom or an aliphatic hydrocarbon group which may be substituted. Become.
E represents one of S, O, and N-R. However, R represents either a hydrogen atom, an aliphatic hydrocarbon group which may be substituted, or an aromatic hydrocarbon group which may be substituted. ) The display element according to claim 1, wherein the polymer compound includes all repeating units represented by the general formulas (1) to (3) in a main chain. The display element according to claim 1, wherein the polymer compound has a molecular weight of 3000 or more and 50000 or less. The polymer compound has a —COOH, —P═O (OH) ₂ , —OP═O (OH) ₂ , —NCO or —Si (OR) ₃ (R represents an alkyl group) group. The display element according to claim 1, wherein the display element is a display element. The display element according to claim 1, wherein the electrolyte composition contains a silver salt compound that dissolves and precipitates by an electrochemical oxidation-reduction reaction.

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