JPS5952193B2 - color display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Conventionally, spiropyran compounds have been well known as materials that decolorize and develop, but they require a large amount of energy to cause decolorization and have poor stability.

The present invention provides a method of discoloring or decoloring by applying a small amount of external stimulus energy, and a solution containing a stable styryl-like compound and using an aprotic polar solvent as a solvent, at least one of which is coated with a dielectric material. The present invention relates to a color display device characterized by being inserted between two transparent electrodes.

The styryl analog compound is represented by the following general formula, as shown in the specification of Japanese Patent Application No. 49-108090 (see Japanese Patent Publication No. 57-33307).

Here, Q represents a substituent and/or benzene with or without a condensed ring. Y represents O or S. Z represents an alkyl group necessary to form a cyclic structure with -N-C-Y-. 2 to 4 carbon atoms with or without substituents
represents an alkylene group. A is represented by .

Z represents an alkylene group having 2 to 4 carbon atoms with or without an alkyl substituent necessary to form a cyclic structure with -N-C-Y-; The reason why it is allowed is that there is no change in the essential operation even if the alkyl substituent is present.

Examples of the benzene ring aldehydes include benzaldehyde derivatives and cinnamaldehyde derivatives, such as benzaldehyde, P-acetaminobenzaldehyde, P-bromobenzaldehyde, . m-bromobenzaldehyde, O-bromobenzaldehyde, P-dimethylaminobenzaldehyde, P-diethylaminobenzaldehyde, P-dibutylaminobenzaldehyde, 0-
Chlorbenzaldehyde, P-chlorobenzaldehyde, P-anisaldehyde, O-anisaldehyde, P-
tolualdehyde, m-tolualdehyde, 0-tolualdehyde, 0-ethoxybenzaldehyde, . P-ethoxybenzaldehyde, P-fluorobenzaldehyde,
0-fluorobenzaldehyde KP-nitrobenzaldehyde, m-nitrobenzaldehyde, O-nitrobenzaldehyde, P-cyanobenzaldehyde, 0-cyanobenzaldehyde, 2,4-dichlorobenzaldehyde, 2,6-dichlorobenzaldehyde , 3,4-dichlorobenzaldehyde, 3,5-dichlorobenzaldehyde, 2,4-dimethoxybenzaldehyde, 2,5-dimethoxybenzaldehyde, 3,4-dimethoxybenzaldehyde, 3,5-dimethoxybenzaldehyde, 2
, 4-dimethylbenzaldehyde, 2,5-dimethylbenzaldehyde, 3,4-dimethylbenzaldehyde,
3,5-dimethylbenzaldehyde (3,4-dimethoxybenzaldehyde), 4-isopropylbenzaldehyde, O-(2-chloroethyl)benzaldehyde, 2
, 4,6-trimethylbenzaldehyde (tankaldehyde), 2,4,6-triethoxybenzaldehyde, 3,4-dimethyl-P-anisaldehyde, 2,5-
Dimethyl-P-anisaldehyde, 2-chloro-5-nitrobenzaldehyde, 2-chloro-6-nitrobenzaldehyde, 2-chloro-3-nitrobenzaldehyde, 5-chloro-2-nitrobenzaldehyde, vanillin, 0 -vanillin, isovanillin, 5-promovanillin, 2-chloro-4-dimethylaminobenzaldehyde,
2-chloro-6-fluorobenzaldehyde, 5-promoveratraldehyde, 5-bromovelatraldehyde, 5-bromo-2-methoxybenzaldehyde, 1-naphthaldehyde, 2-naphthaldehyde, P-dimethylaminocinnamaldehyde , P-diethylcinnamaldehyde, P-nitrocinnamaldehyde, 0-nitrocinnamaldehyde, 2-chlorocinnamaldehyde, condensed benzene ring aldehydes include those of 2- to 4-ring systems, such as 1-naphthaldehyde, 2- Examples include naphthaldehyde, 9-anthraaldehyde, 10-chloro-9-anthraaldehyde, 9-phenanthrenecarboxaldehyde, fluorenecarboxaldehyde, and the like.

Examples of nitrosobenzene derivatives include P-dimethylaminonitrosobenzene, P-diethylaminonitrosobenzene, P-methylnitrosobenzene (P-nitrosotoluene), P-nitronitrosobenzene, 0-nitronitrosobenzene, and 3-nitrosobenzene. -Nitrotoluene, etc.

Examples of heterocyclic aldehydes include furfural, 5-methylfurfural, 5-promofurfural, 4-isopropylfurfural, 2-thioquenecarboxaldehyde, 5-methylthioquenecarboxaldehyde, and 3-methoxybenzothioquene. -2-carboxaldehyde, 2-pyridinecarboxaldehyde, 3-pyridinecarboxaldehyde, 4-pyridinecarboxaldehyde, 1-ethylindole-3-carboxaldehyde, 1-methylindole-3-carboxaldehyde,
1-Methyl-2-phenylindole-3-carboxaldehyde, N-methylcarbazole-2-carboxaldehyde, N-ethyl-promocarbazole-2-carboxaldehyde, N-(n-octyl)- J Me[nitrocarbazole-2-carboxaldehyde, benzofuran-2-carboxaldehyde, dibenzofuran-2-carboxaldehyde, pyrrole-2-aldehyde KN-methylpyrrole-2-aldehyde, N-phenylpyrrole-2
-aldehyde, 3-methylpyrrole-2-aldehyde,
2-ethylpyrrole-5-aldehyde, benzothiazole-2-alf-hydrogen, 6-methylbenzothiazole-2
-aldehyde, 6-chlorobenzothiazole-2-aldehyde, 5-chlorobenzothiazole-2-aldehyde, 6-methoxybenzothiazole-2-aldehyde, 5
, 6-dichlorobenzothiazole-2-aldehyde, benzoselenazole-2-aldehyde, 6-methoxybenzoselenazole-2-aldehyde, 2,4-dimethylpyrrole-2-aldehyde, 4,6-dichloropyrimidine-5- Carboxaldehyde, 2-formyl-4,6-dimethylpyrimidine, quinoline-2-aldehyde, acridine-10-aldehyde, 2,4-diphenyl-5,
6,7-hexahydrobenzopyran-8-carboxaldehyde, 2,4-diphenyl-6-methyl-5,6,
Examples include 7-pentahydrobenzopyran-8-carboxaldehyde. Also, as heterocyclic nitrosonondole derivatives (eg, 3-nitrosoindole, 2-methyl-
Examples include 3-nitrosoindole (3-nitrosomethylketol) and 3-nitroso-2-phenylindole.

Characteristics of the series of styryl-like compounds used in the present invention include the following facts.

(1) With the exception of some compounds, most of the compounds have absorption in the ultraviolet region and are colorless to pale yellow compounds. (2)
These compounds can be controlled by electrical signals applied between two electrodes.
It transitions to an indolenium-type ring-opening color-forming structure represented by the following general formula [], and becomes a color-forming dye that extends from the near-ultraviolet region to the entire visible and near-infrared region.

Here, Z represents an anion such as a halogen, an acid radical, or an alkoxy anion. Dyes with an (auto)indolenium-type ring-opening coloring structure return to their original indoline-type ring-closing coloring structure by applying a force that provides an electrical signal in the opposite direction, or by removing the electrical signal. (4) By selecting the conditions for these reversible changes in color development, decolorization, or color change, the repeat life can be considerably long and the stability can be further improved. Next, a method for producing a styryl-like compound will be described in detail.

The present invention is one of the starting materials.

The methyl group or methylene group at the 2-position of the described indoline derivatives is active, and the aldehyde group or nitroso group of an aromatic, heterocyclic alkali, or aromatic heterocyclic nitroso compound and S is in the presence of an alkali catalyst or in the absence of S. Initiating a dehydration condensation reaction to give a condensation product, and general formula [
A styryl-like compound can be easily obtained by treating styryl pigments having the structure represented by the above with an alkali.

In addition, the styryl-like compound represented by the general formula [I] is prepared by combining an indoline derivative, which is one of the starting materials, and an aromatic or heterocyclic aldehyde, or an aromatic or heterocyclic nitroso compound in the absence of a solvent in the presence of an alkali catalyst. Or melt it by heating in the absence of it. 2. Heat the reaction in a non-polar solvent.

3. Heat the reaction in an aprotic polar solvent.

The reaction is carried out in a 4-proton type solvent in the presence of an alkali catalyst.

5. Add an alkali catalyst to react in a nonpolar, nonpolar, or aprotic polar solvent or a suitable mixed solvent thereof.

? It can be obtained by reacting in a proton-type polar solvent. In addition, the above indoline derivative and the above aldehyde or nitroso compound are mixed in a protic solvent or a mixed solvent of a protic solvent and one or more nonpolar, nonpolar, or aprotic polar solvents without using an alkali catalyst. When the reaction is carried out, the target compound represented by the general formula [I] is obtained, and when this compound is reacted with the general formula []
A by-product compound (by-product pigment) represented by a type may be obtained. When obtained as a mixture, only the target compound can be easily obtained by separating the two using a fractionating solvent such as ether, benzene, ethyl acetate, n-hexane, or cyclohexane. In addition, when the above-mentioned indoline derivative and the above-mentioned aldehyde or nitroso compound are reacted in acetic anhydride, acetic acid, or a mixed system thereof,
Only indolenium-type styryl dyes represented by the general formula [] can be obtained. In such cases, an alkali agent is added to the reaction system, or the crude product once isolated is dissolved in an appropriate solvent, an alkali agent is added thereto, and if necessary, the mixture is heated appropriately to obtain the general formula [] The target compound represented by can be obtained. In addition, when the target compound and indolenium-type styryl dyes are obtained by reacting an indoline derivative with an aldehyde or a nitroso compound in a proton-type solvent or a mixed solvent with other solvents without using an alkali catalyst. The desired compound can be obtained by adding an alkali agent to this reaction system or to a system in which the isolated mixture is dissolved in a suitable solvent and heating as appropriate if necessary.

Next, examples of styryl-like compounds are shown, and the maximum absorption wavelength when the ring is closed and the maximum absorption wavelength when the ring is opened are shown. Examples of other styryl-like compounds include those shown in the specification of Japanese Patent Application No. 108090/1982 (see Japanese Patent Publication No. 33307/1983). [I] 3,3-dimethyl-2-(P-dimethylaminostyryl) indolino [1
, 2-b] Oxazoline 3,3-dimethyl-5-methoxy-2-(P-dimethylaminostyryl)indolino[1,*. 2-b]Oxazoline CV)3,3-dimethyl-5-nitro-2-(P-dimethylaminostyryl)indolino[1,2b]Oxazoline[]3,3,5
-Trimethyl-2-(P-dimethylaminostyryl)indolino[1,2-b]oxazoline[]3,3-dimethyl-2-(P-chlorostyryl)indolino[1,2
-b]Oxazoline[]3,3-dimethyl-5-chloro-2-(P-chlorostyryl)indolino[1,2
-b]Oxazoline α]3,3-dimethyl-5-chloro-2-(P-dimethylaminostyryl)indolino[1
,2-b]oxazoline[03,3-dimethyl-5-iodo-2-(P-didimethylaminostyryl)indolino[1,2-b]oxazoline 0(D3,3-dimethyl-4,5-penso2 -(P-dimethylaminostyryl)indolino[1,2-b]oxazoline α13,3-
Dimethyl-4,5-penso-2-(P-dimethylaminostyryl)indolino[1,2-b]-1,3-tetrahydroxazine α13,3-dimethyl-2-(P-
dimethylaminocinnamylidene vinyl) indolino [1
,2-b]oxazoline]V)3,3-dimethyl-5-
Chloro-2-(P-dimethylaminocinnamylidenevinyl)indolino[1,2-b]oxazoline[XV]3
,3-dimethyl-5-methoxy-2-(P-dimethylaminocinnamylidenevinyl)indolino[1,2-b]
Oxazoline CXV])3,3-dimethyl-2-(P-
dimethylamino-2-azastyryl) indolino [1,
2-b]Oxazoline α 3,3-dimethyl-5-methoxy-2-(P-dimethylamino-2-azastyryl)indolino[1,2-b]Oxazoline α]3,3-
Dimethyl-5-chloro-2-(P-dimethylamino-2
-azastyryl) indolino[1,2-b]oxazoline Next, well-known organic solvents, oils, etc. are suitable as the solution for dissolving the above-mentioned styryl analog compounds.

In particular, organic solvents that are aprotic and have high inductivity, such as dimethyl sulfoxide, dimethyl foramide, and propylene alcohol, have higher sensitivity and require lower driving voltages.
As for the oil, oils with higher dielectric factors such as cresyl diphenyl phosphate, tricresyl phosphate, and tetramethylene sulfone have higher sensitivity and require lower driving voltage. Further, as the dielectric material covering the electrode surface, organic materials and inorganic materials are generally used, but oxides, nitrides, and fluorides are particularly suitable.For example, NlO. Y2O3
, TlO2, WO, , Fe2O, , SiO2, LiNb
O3, BaTlO3, Al2O3, BaO. La2O,
, Ll2O, MgOxMOO3, SrOXTa2O,,
01205, ZrO2, PbO. Sb2O3, TeO2
, ZnO, SiNx. , CeF3, MgF6BeF2,
Suitable materials include CaF2, LiF, ThF4, and LaF2, which can be easily formed into a thin film.

For organic materials, the higher the dielectric constant, such as polyvinylidene fluoride, cyanoacetylcellulose, and polyvinylpyridine, the higher the sensitivity and the lower the driving voltage. As the transparent electrode, a well-known film of In2O3, SnO2, or a mixed oxide film thereof is used. Next, embodiments of the present invention will be described in detail. An In2O3 film is formed on one side of the glass by vacuum evaporation, and a WO film is also formed thereon by vacuum evaporation.

These two glass plates are used to create a cell as shown in Figure 1 using a spacer made of polyethylene terephthalate, Teflon, glass, or the like. Epoxy resin, low melting point glass, etc. are used for sealing. In Figure 1, 1 is glass, 2 is In2O
3 is a membrane electrode, 3 is WO3PL4 is a spacer. In this cell, 3,3-dimethyl-2 represented by the structural formula [plate]
-(P-dimethylaminostyryl)indolino[1,2
-b] Oxazoline in dimethyl sulfoxide 5×1
0-3 m01/t is dissolved, and the solution 5 is sealed in the internal space shown in FIG. When an alternating current voltage is applied to the cell made in this way, it develops a pink color. When a DC voltage is applied, the color develops only immediately after application, and gradually fades. (119
In order to develop this color with even higher sensitivity, it is recommended to add a cationic surfactant such as dodecylpyridinium fluoride to the above-mentioned solution.

This is thought to be because the anion of the cationic surfactant attacks the N of the indoline ring of the styryl-like compound and facilitates ring-opening color development. For such cationic surfactants, good results were obtained when the concentration was about 1×10 −4 to 1×10 −1 m01/t.

FIG. 2 shows the change in absorbance of color development depending on the applied voltage when the concentration of the cationic surfactant was changed. The higher the concentration of the cationic surfactant, the easier it is to develop color. In this case, as already mentioned, the solute (pigment) is 3,
3-dimethyl-2-(P-dimethylaminostyryl)indolino[1,21b]oxazoline, the solvent is dimethyl sulfoxide, the cationic surfactant is dodecylpyridinium fluoride, and there is no cationic surfactant. In this case, a faint color develops, but when absorbance was measured in the cell state, the sensitivity was at the limit, so it was not shown in FIG.

The example of 003) is very easy to color, but
The decoloring speed is slow when the voltage is turned off.

Therefore, when a small amount of a proton-donating additive such as hydroquinone is added, the response speed is significantly improved. FIG. 3 shows the relationship between hydroquinone concentration and decoloring time. The higher the hydroquinone concentration, the faster the decoloring speed. The composition in this case is the composition of the upper ridges plus hydroquinone, and the decoloring time is the time for the absorbance to fall from 90% to 10%. The distance between the electrodes was approximately 16μ.
Note that the measurement temperature was room temperature. (6) Dielectric and Y2O3
The film was coated on an In2O3 film by a sputtering method to make a cell as shown in Figure 1, and 3,3-dimethyl-2-(P-dimethylaminocinnamylidenevinyl)indolino of structural formula 1 was used as a styryl-like compound. [1721b
] The oxazoline is dissolved in 1 x 10-2 m01/t tricresyl phosphate and sealed in the cell of Figure 1.

When a voltage was applied to this cell, it developed a blue color, but even if the thickness of the dielectric Y2O3 film was changed, no difference was observed due to the applied voltage because the thickness was very thin. Although the thickness of the dielectric varies depending on the material, it is generally about 1000 λ from the state where the dielectric is not a film having an island-like structure. Further, the color density and response characteristics can be improved by using a cationic surfactant, hydroquinone, etc., as described above.

(g) 3,3-dimethyl-5-chloro-2-(para-dimethylaminostyryl) represented by the structural formula [X] in place of the styryl analog compound in D above.
In the case of indolino[1,2-b]thiazoline, the color was yellow when no voltage was applied to the cell, but changed to red when a voltage was applied.

Furthermore, as in the present invention, since there is a dielectric film on the electrode surface, the electrode reaction due to voltage application is suppressed, and this has a remarkable effect on improving the life of the color display device. As described above, the color display device of the present invention has the advantage of being able to perform color decolorization with a small amount of energy, has good stability, and has a long service life.

Claims (1)

[Claims] 1 The following general formula ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (In the formula, Q represents a benzene ring with or without a substituent and/or a condensed ring. Y is O or represents S. Z represents an alkylene group having 2 to 4 carbon atoms with or without an alkyl substituent necessary to form a cyclic structure together with ▲ has a numerical formula, chemical formula, table, etc.. A represents ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼▲ There are mathematical formulas, chemical formulas, tables, etc. ▼▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
Or ▲ represents a mathematical formula, chemical formula, table, etc. ▼. A color display device characterized in that a solution containing a compound represented by the general formula () in an aprotic polar solvent is inserted between two electrodes coated with a dielectric, at least one of which is transparent.