JPS5838781A - Electrochromic display element - Google Patents

Abstract

PURPOSE:To provide the titled display element capable of developing desired color and having excellent display stability in repeated use, by using a specific phenazine derivative as an electrochromic substance which can be colored and quenched reversibly by the oxidation reduction reaction induced by the application of electrical potential. CONSTITUTION:A phenazine derivative of formula (R1-R4 are H, Cl, Br, I, F, 1-6C alkyl, alkoxy, NO2, NH2, COOCH3, SO2NH2, etc.; R5 and R6 are H, acyl, alkyl or phenyl) (e.g. 3,7-diamino-5-phenyl-5,10-dihydrophenazine) is used as an electrochromic substance, and is dissolved in water and/or an organic solvent preferably in a concentration of 1X10<-5>-5mol/l. The solution is mixed with tetraethylammonium perchlorate, etc. (preferably 0.01-5mol/l) as supporting electrolyte and white inorganic sigment, etc., and the mixture is filled in an electrochromic element to obtain the objective display element.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display element using a novel organic electrochromic material that reversibly develops and fades color through redox reactions caused by voltage application.

In an electrochromic display element (hereinafter abbreviated as a POD element), when a voltage is applied, an oxidation or reduction reaction of the EC substance occurs at the transparent display electrode, forming a colored pattern, and when a voltage of opposite polarity is applied. It uses a mechanism in which the colored pattern disappears through a reverse reaction.

The ECD element, which develops and erases color using this mechanism, has no viewing angle dependence compared to the liquid crystal that has been conventionally used as a light-receiving display element, and has a bright color display that is easy to see, and has a memory function. It is attracting attention because it has many excellent features such as high temperature, wide operating temperature range, and ease of making large screens.

Typical EC substances that have been proposed so far include organic compounds such as viologen derivatives (4,4'-bipyridine derivatives) and inorganic compounds such as tungsten oxide (WO) and molybdenum oxide (MoOn). be.

Among these, organic compounds have the advantage of being able to display more vivid colors than inorganic compounds, and that a variety of colors can be selected depending on the selection of the poem's font.

However, at present, ECD elements using organic compounds have not reached the level of practical use due to their short repeated display life and insufficient memory life. Moreover, the types of colors that can be produced are relatively limited υ, and there is a need for new EC substances that can produce any color and have good repeat stability in display.

The present invention discovered that an organic compound that has not been known as an Ice substance has properties as an EC substance that satisfies the above requirements, and the I! ! This paper proposes a 9mOD element with a configuration suitable for c-materials.

The KOD element according to the present invention utilizes the color development/discoloration caused by oxidation/reduction of a phenazine derivative, which is represented by the following general formula.

R/ R Niko, in the formula R, ~R, is H, C1, By, Engineering, 7%01
C6 alkyl group, alkoxy group, phenoxy group,
No,,ON%NH2,N(OH,),,0OOH%c
OOOH,, S O, N H3, S osN,
The fox and the bird represent H, an acyl group, an alkyl group, and a phenoxy group.

These phenazine derivatives can be obtained by general synthetic methods as shown below.

Or, 5 To construct an EcD element using these heptanazine derivatives, they can be dissolved in an organic solvent such as water or DMF, or a mixed solvent of water and an organic solvent at a concentration of tx16-' to 5 mol 1. A supporting electrolyte is mixed in to disperse and further increase conductivity. Examples of supporting solutes include lithium chloride, potassium chloride, sodium chloride, potassium bromide, potassium sulfide, ferrous sulfate, potassium perchlorate, lithium perchlorate, tetraethylammonium perchlorate, potassium borofluoride, Potassium phosphate, potassium vinegar rice, etc. are used in the range of 0.01 to 5 mo/I/1 depending on the purpose. Furthermore, a white inorganic pigment or a polymer emulsion is dispersed to improve the contrast of the display. This is also effective, and it is also possible to mix at least the same amount of white inorganic pigment into the solution and use the entire solution as a paste.

The EC material prepared in this way was prepared as shown in Figure 1.
When the transparent display electrode FM (2) is set as positive and a DC voltage is applied between it and the counter electrode (3), a vivid color display can be obtained through the display electrode (2).

In addition, the phenazine derivative according to this invention [-]
One example of the configuration of an OD element is shown in FIG. That is, a phenazine derivative and a polymeric binder resin are mixed and coated on the surface of the display electrode (2) to form a film-like KO material layer (6). As the polymer binder resin used here, preferably a conductive polymer electrolyte is suitable. In this case, the KOD element is filled with a solution (7) consisting of the above-mentioned supporting electrolyte, inorganic electrolyte, and the like.

The color tone displayed by the ECD element configured in this manner varies depending on the phenazine derivative used.

For example, 8.7 diamino-6pheni/l/-5, 1O dihydrophenazine (in the general formula, R1 and NH are NH, %R8
, to, - is a phenyl group) is initially white, but by applying a voltage with the display pole as positive, it changes to a vivid reddish-purple color, and by applying a voltage in the opposite direction, it quickly changes to its original color. Return to white. This repetition of coloring and decoloring could be performed stably, and an element with excellent display characteristics could be obtained.

Furthermore, by selecting substituents R1 to R6 in the general formula, it is possible to obtain display of other color tones.

As described above, the InCD element using the phenazine conductor according to the present invention is novel and has various color tones. It is characterized by stable repeated display characteristics.

This invention will be specifically described below with reference to Examples, but the invention is not limited thereto.

Example 1 98.7-Diami2 5 synthesized by reducing Safranin 0
-Fenyl/v-5,1G-dihydrophenazine 0.5
P, tetraethylammonium perchlorate 0,255E
, 1.25 F of titanium oxide, and 2.6 F of zinc oxide were added to 2.6 F of dimethylformamide and mixed uniformly, which was filled into the +131) device to create an EOD device shown in No. 17.

When voltage is gradually applied with the transparent display electrode as positive, a current indicating that an oxidation reaction is occurring is observed, and O, S
With V, a reddish-purple display with good contrast was obtained. When a voltage of opposite polarity was applied, the color quickly disappeared, and the repetition of color development and color erasure was performed stably.

Example 2 2-Methi IV synthesized by reducing neutral red
-8-Amino-7-dimethenio-5,10-dihydrophenazine IP, tetraethylammonium perhydrochloride o
, by titanium hydride 2.5F1 synthetic powder zeolite s,
A homogeneous mixture of OP and dimethylformamide 64 was filled into the waD element, and the FF shown in FIG. 1 was filled.
A 1cD device was created.

When voltage was gradually applied with the transparent element electrode set as positive, a red display with good contrast was obtained at 10.6V.

When a voltage of opposite polarity was applied, the color quickly returned to white, and this cycle of coloring and decoloring was performed stably.

Example 8 1 was prepared in the same manner as in Example 2 except that 5, 1O-dipenzoy 1v-5, 1O-dihydrophenazine synthesized by benzoylation of 5, 1O-dihydrophenazine was used.
[An ICD device was created.

When a voltage was applied with the display electrode side set as negative, the color turned purple at -1.6V, and when a voltage with the opposite polarity was applied, the color returned to white.

Example 4 80% methanol/L/ of ammonium polyacrylate
A bath solution prepared by adding 8,7-dibumid-6-phenyl-5,10-dihydrophenazine IF to dissolved ffx5WLt was coated on a transparent display electrode to form a film with a thickness of 2 μm. Using this, an ECD element was assembled, and a 0.8 molar A/1) aqueous solution of potassium sulfate was sealed inside.
The mOD device shown in the figure was created.

By applying a voltage with the display electrode side as positive, fi +
At 1.2 V, a reddish-purple display with good contrast was obtained. When a voltage of opposite polarity was applied, the color quickly disappeared, and the repetition of color development and color erasure was performed stably.

The present invention provides a display element using an electrochromic substance that develops or decolors the substance due to an oxidation/reduction reaction that occurs reversibly when a DC voltage is applied. In the formula, ~- are respectively) I, C1, B, Engineering, F
% negative ~ C6 alkyl group, alkoxy group, phenoxy group, No, CN% NH! , N (C! Hs)t, 0O
OH, 0OOCH3, S O, N H, or S os
N, and RIs R11 are H, acyl μ group,
It is characterized by using a phenazine fatty conductor represented by an alkyl group or a phenyl group, and has the effect of being able to display various colors and extending its life.

[Brief explanation of the drawing]

FIG. 1 shows an OD element using the ZC material according to the present invention.
A sectional view of one embodiment, and FIG. 2 is a sectional view of another embodiment of the invention. In the figure, (1) is a galanic substrate, (2) is a transparent display electrode, (3) is a counter electrode, (4) is a solution containing an electrochromic substance, (5) is a spacer, and (6) is a film of K.
(3 material layers, <7) is an electrolyte solution. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Makoto Kuzuno (1 person) Figure 1 Figure 2

Claims (1)

[Claims] (1) In a display element using an electrochromic substance that causes coloring or decolorization of the substance in question due to an oxidation/reduction reaction that occurs reversibly when a DC voltage is applied, the electrochromic substance is expressed by the general formula below. An electrochromic display element characterized by using a phenazine derivative. Umahachi (However, in the formula, R8 to R8 are respectively H, Cu2, B7, F, O, -0, alkyl μ group, alkoxy group, phenoxy group, No & ON% IJH, N (CH4) 1% coo
g, cooaa3, So, NHI or 5O8N, υ, R8% R1 is u1 aplv group, alkyl μ, respectively
or phenyl group).