JPS61203194A - Electrochromic display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to display devices, particularly organic electrochromic (
Electrochromic display device using E C) material (
(hereinafter abbreviated as ECD).

Organic ECD using organic EC materials can be multicolored,
Although it is expected to be put into practical use because of its theoretical advantages such as clear images, it has not yet been put into practical use. The first main reason for this is insufficient operational stability. Typical organic ECDs currently being proposed and under development use viologen as the EC material (Reference Applied Physics x
-shi9-su(Appl, Phys, Lett, , 2
B (1978), P64) is a stable operating 0N-O.
The FF repeat life is about 10 times in our test results, which is insufficient compared to the minimum life of 10 times required for practical use. The cause of this operational deterioration is color development - color decolorization (ON-OFF)
It is said that this is due to the incomplete reversibility of the precipitation-redissolution phenomenon of viologen that accompanies this phenomenon, but the exact details are unknown.

The second problem is that the display color is a purple-colored color unique to the viologen type, and cannot sufficiently meet market demands for diversification of display colors. Furthermore, the purple color of viologen is not necessarily suitable as a standard display color, which is one of the reasons why it is not accepted in the market.

An object of the present invention is to provide a novel organic ECD that has display colors suitable for a display device and also has stable reversible coloring and decoloring operations.

That is, the present invention provides an electrochromic display device including a solution in which an organic material capable of electrochemically reversibly coloring and erasing color and a supporting electrolyte is dissolved, and a pair of electrode substrates that sandwich the solution. The following compound (1) [wherein R represents an alkyl group, aryl group, aralkyl group or cycloalkyl group, R1°R2 represents a hydrogen atom, an alkyl group, a halogen atom or an -OR group,
-OR group and R2 group may form a ring.

In the substituents R, Rt, and R2, the alkyl chain and aryl ring may be substituted. ] is an electrochromic display device characterized by containing one or more kinds.

Compound (In D, the substituent R is a methyl group.

Ethyl group, propyl group, butyl group, amyl group.

Linear or branched alkyl groups such as hexyl, octyl, and dodecyl groups, methoxyethyl, ethoxyethyl, and methoxypropyl groups.

Substituted alkyl groups such as phenoxyethyl group, chloroethyl group, hydroxyethyl group, phenyl group, methylphenyl group, ethylphenyl group, butylphenyl group, hexylphenyl group, nonylphenyl group, dodecylphenyl group,
Aryl groups such as dimethylphenyl group, chlorphenyl group, methoxyphenyl group, phthoxyphenyl group, hexyloxyphenyl group, benzyl group, methylbenzyl group,
7-ralkyl groups such as phenethyl group, α-methylhensyl group, methoxybenzyl group, chlorobenzyl group, cycloalkyl groups such as cyclohexyl group, methylcyclohexyl group, cyclopentyl group, butoxycyclohexyl group,
R1 and R2 are hydrogen atoms and methyl groups.

A linear or branched alkyl group such as an ethyl group, a butyl group, a pentyl group, a halogen atom such as a chlorine atom, a fluorine atom, a bromine atom, or a 10-R group or 10-R group having the above meaning and R2 As those forming a ring with the group, -0-CF12CH2-0- group, -0-CF12CH
-0- group.

and Ill [3 Examples of substituents include groups.

Next, FIG. 7, which also explains the present invention, is a sectional view showing an example of a display device of the present invention.

In the figure, 1 and 2 are glass substrates, 8 is a display electrode made of an ITO (indium tin oxide) film or a tin oxide (8n02) film, and 4 is ITo.

8n02 or a counter electrode made of a metal film such as stainless steel or platinum, or a film obtained by pressing carbon or a mixture of an iron complex and carbon; 5 is an EC solution in which an organic EC material and a supporting salt are dissolved; 6 is a ceramic thin plate such as alumina, or It is a porous light scattering material such as a thin polymer plate. The electrode substrate consists of a glass substrate and an electrode. As the porous scatterer, titanium oxide (T i 02), alumina (A/z
An insulating or semiconducting white powder such as os) may also be used. As the EC solution material, any solvent can be used as long as it has high polarity and is electrochemically stable, such as propylene carbonate, dimethylformamide, N
-A non-aqueous solvent such as methyl-2-pyrrolidone is used.

Quaternary ammonium and perchloric acid O1!0 are used as supporting salts.
4. Quaternary ammonium salts such as salts with halogens, fluoroborates BF4 and fluorophosphates PFs are used, and are used at concentrations of 0.05 to 1.0 mol/l.

Examples of the compound represented by compound (I) include the following.

The compound of general formula (I) is usually 0.01 to 1.0 mol/
It is used at a concentration of j.

Compounds of the general formula (D) are, for example, Methoden d
erOrganischen Chemie 780
, 1979 (Georg Th+eme Verla
It can be manufactured according to the Taga method.

If the compound of the present invention is used alone as an organic material capable of electrochemically reversibly coloring and decoloring, it is possible to construct a display device that generates color when a negative voltage is applied to the display electrode between the display electrode and the counter electrode. Furthermore, the compound of the present invention is mixed with a compound having a reverse polarity 8, that is, a compound (type 0 compound) that develops a hue different from that of the compound of the present invention when the display electrode becomes a positive voltage, and the polarity of the voltage applied to the display electrode is It is possible to change the display color by controlling .

The type 0 compound is tetrathiafulvalene (TTF
), pyrazoline derivatives, diphenylamine derivatives, fluorene derivatives, etc. are known.

Next, the present invention will be explained with reference to Examples.

Example 1 In a display device equipped with a display electrode and a counter electrode, 0.8 mol/l of tetrabutylammonium iodide was added to propylene carbonate! A solution in which Compound A1 was dissolved at a concentration of 0.02 mol/l was sealed.

When a voltage of 1.5 to 2.0 cm is applied between the display electrode and the counter electrode of the display device so that the display electrode side becomes a negative voltage, the display surface becomes a clear red color (λmax 595) on a white background.
It exhibits color development (nm), and disappears when the voltage is Ov or the polarity is reversed.

When we tested the device's repeated coloring and decoloring operations, we found that:
It showed very high stability.

Examples 2 to 6 The same procedure as in Example 1 was carried out except that Compound AI was replaced with the following compound, and the results shown in the table below were obtained.

Operational stability was good in all cases.

Example 7 In a display device provided with a display electrode and a counter electrode, 9.3% of tetrabutyl fluporolate was added to propylene carbonate.
mol/l! , compound &l 0.02 mol/
A solution in which 4 and 2-aminofluorene were dissolved to a concentration of 0.02 mol/l was sealed.

A voltage of -1.5 to 2.0 is applied between the display electrode and the counter electrode of the display device so that the display electrode side has a negative voltage. When applying OV,
The display surface showed a clear red color on a white background, and the color disappeared when a voltage of about Ov or +0.6 .mu. was applied. Furthermore, the voltage is +1.5 to +2.0 so that the display electrode has a positive voltage. When Ov is applied, a blue color is obtained, and when the voltage is applied to 0 or -0,
The color disappeared quickly when about 5 cm of water was applied.

Example 8 A display device having the same configuration as Example 7 except that 0.02 mol of 4,4-bis(dimethylamino)diphenylamine was used instead of 2-aminofluorene in Example 7 was as follows:
When a positive voltage was applied to the display device, the same effect as in Example 7 was obtained except that green coloring was obtained.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention. In the figure, 1.2 is a glass substrate, 8 is a display electrode, 4 is a counter electrode, 5 is an EC solution, and 6 is a porous light scatterer.

Claims (1)

[Scope of Claims] An electrochromic display device comprising a solution in which an organic material capable of electrochemically reversibly coloring and decoloring and a supporting electrolyte are dissolved, and a pair of electrode substrates sandwiching the solution, wherein the organic material An electrochromic display device comprising one or more of the following compounds (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) [In the formula, R is an alkyl group, an aryl group, an aralkyl group, or a cycloalkyl group, and R_1 and R_2 represent a hydrogen atom, an alkyl group, a halogen atom, or an -OR group. , -O
The R group and the R_2 group may form a ring. In the substituents R, R_1, and R_2, the alkyl chain and aryl ring may be substituted. ]