JPS60221731A - Polychromatic display device - Google Patents

Abstract

PURPOSE:To display different information in different color by changing the potentials of an electrode for applying an electric field to a conductive layer consisting of an electrolytic solution containing a material which colors by oxidation and a material which colors by reduction. CONSTITUTION:The display electrode 1 of an electrochromic display device is formed by laminating a transparent glass substrate 2, transparent ITO electrode layer 3, and transparent SiO2 insulating layer 4 successively. The pattern 5 of a character ''violet'' and the pattern 6 of ''blue'' are formed on the insulating layer 4. The pattern 5 is formed deeply enough to reach the surface of the electrode layer 3 and the pattern 6 is formed deeply enough to reach the surface of the electrode layer 3, and then a prussian blue thin film is adhered to an exposed electrode layer part. The electrode 1 is fixed to the counter electrode 12 consisting of a transparent electrode 8 and a transparent ITO electrode layer 9 across a spacer 11, and an electrolyte 13 containing heptylviologen is charged in it. Then, an electric field is applied to display the pattern 5 in purplish red, the patterns 5 and 6 transparently, and the pattern in blue.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrochromic display device (hereinafter referred to as EOD) capable of repeating recording, and particularly relates to a multicolor EOD.

BACKGROUND TECHNOLOGY AND PROBLEMS EOD is a display device that utilizes the phenomenon of reversible color change due to the application of an electric field (electrochromism). Various RODs are known, such as ROD, solution type, and solid type. There is.

Solution-type Fm0D is a solution-type Fm0D in which a substance that colors or changes color when an electric field is applied (hereinafter referred to as EC substance) and an electrolyte are sealed in an EOD cell, and display is performed by applying an electric field to the electrolyte. Dissolution disk in which EC substance is dissolved in electrolyte before and after application of electric field, and EC dissolved in electrolyte
There are two types: a precipitation type in which the substance is deposited on the electrode after an electric field is applied, and a fixed type in which the EC substance is fixed on the electrode before and after the electric field is applied. However, their E
OD is a monochromatic EOD, and a display is performed by coloring or changing the color of one type of EC material by applying an electric field.

It is clear that if a multicolor EOD capable of displaying various information in anisotropic colors could be obtained, it would be more convenient than the conventional monochrome FiOD, and its development was strongly desired.

As an EOD that can display multiple colors, an EC substance that develops color upon reduction (hereinafter referred to as reduced EC substance) and a substance that develops color upon oxidation (hereinafter referred to as oxidized EC substance) are dispersed in a synthetic polymer. An all-solid-state EOD consisting of a colored active material layer and this layer provided on a display electrode was disclosed in Japanese Patent Application Laid-Open No. 58-80625.
It is disclosed in the publication No. This all-solid-state EOD is in a colorless state when the applied voltage is Ov, and performs multicolor display by applying a voltage. However, in the application of nOD, there are extremely many cases in which a certain color display is always performed and a different display is performed as necessary.

Purpose of the Invention In view of the above-mentioned points, the present invention provides a multicolor nOD using an electrolyte aqueous solution and an EC substance, by constantly displaying color when no voltage is applied, and by changing the potential of the electrodes as necessary. The present invention provides a multicolor ECD that displays different information in different colors.

Summary of the Invention The multicolor EOD of the present invention comprises an oxidized EC material and a reduced layer EC.
It has a conductive layer made of a substance and an aqueous electrolyte solution, and an electrode connected to a voltage source to apply an electric field to the conductive layer.

In the multicolor EOD of the present invention configured in this manner, when the electrode is in a state of natural potential (a state in which no voltage is applied and an equilibrium potential is maintained with respect to the reference electrode), the color is colored □. By using an oxidized EC material and a colorless reduced fiEO material, it is possible to always display colored information without consuming electricity, and only when necessary, different information can be displayed by changing the electrode potential. displayed in a different color.

It is preferable that the EC material that is colored in the state of the natural potential is fixed on the electrode (display electrode), and for example, an oxidized EC material such as Prussian Blue 4 (FZ (ON) 6)s may be used. It can be quantitatively formed and fixed into a film by electrolytically synthesizing it on an electrode under certain conditions.

The electrolyte contained in the conductive layer is KO1! Ordinary water-soluble supporting electrolytes such as these may be used, and can be used at ordinary concentrations of about 0.1 to 1M.

Hereinafter, a multicolor EOD (7) embodiment of the present invention will be described with reference to the drawings.

Example 1 FIG. 1 shows the display electrode 1 of the ROD of this embodiment.

This electrode 1 consists of a transparent glass substrate 2 and a transparent ITOII electrode layer 6.
and Tooru F! A8i02 insulating layers 4 are sequentially laminated. A pattern 5 with the character "purple" and a pattern 6 with the character "blue" are formed on the insulating layer 4. Pattern 5 is electrode layer 3
It is formed to a depth that reaches the 0 surface. The pattern 6 is formed to a depth that reaches the surface of the electrode layer 3, and then the exposed IT
It is formed by depositing a Prussia blue thin film on the O electrode layer portion by electrolytic synthesis. This electrosynthesis is performed by F' (e.g. FeOjg)
Solution and potassium ferricyanide (K3Fe(ON)6)
Prussian blue is quantitatively synthesized in a mixture of equal volumes of solutions under constant current (low current density of about 10 to 50 μA/saw 2) using the exposed ITO electrode layer portion as a cathode. An Ag-Ago/reference electrode 7 is provided at a suitable position on the insulating layer 4.

The display electrode 1 constructed in this manner is fixed to a counter electrode 12 consisting of a transparent glass substrate 8 and a transparent ITO electrode layer 9 shown in FIG. 2 with an adhesive 10 via spacers 1 and 1f. A cell is formed, and an electrolytic solution 13 consisting of an aqueous solution of 0.05M heptyl viologen and 0.3M KO/0.3M is sealed in this cell to constitute the ROD of this embodiment. In FIG. 2, the display electrode 1 is shown in a cross-sectional view taken along line 1--2 in FIG.

At EOD, the natural potential of display electrode 1 is 0.1V
vs. 8SOB, pattern 6 is blue. By changing the potential of the display electrode 1, a cyclic portamogram shown in FIG. 6 was obtained.

Prussian blue thin film pattern 6 is oxidized in the positive potential region and colored blue, -0, IV vs, 5SOE@
It becomes transparent at certain degrees. On the other hand, heptyl viologen dissolved in the electrolytic solution is reduced to purple and deposited on the pattern 5 at a voltage of 10.5 V vs. 5 SOE or less.

In gaD< of this example, coloring and decoloring of each pattern (
The range of the potential E of the display electrode 1 in which the display electrode 1 (transparent) can be clearly distinguished is as follows.

E≦-0,5V ys, 880B reddish purple (pattern 5
)-0,35V≦E≦-〇, 05 V vs, 880
B transparent (patterns 5 and 6) 0.1≦B vs, B80B blue (pattern 6) In this way, the EOD of this embodiment performs multicolor display on the same display electrode.

Example 2 In this example, an EOD is constructed in which two mutually opposing electrodes are configured as a first display electrode and a second display electrode, respectively.
Describe about. The first display electrode 14 shown in FIG. 4 includes a glass substrate 15, transparent ITO electrode layers 16a to 16c and an 8i02 insulating layer 17 sequentially deposited on the glass substrate 15, and electrode layers 16a to 16c. are insulated from each other by grooves 18 and 19. A letter pattern A is formed on the insulating layer 17 deposited on the electrode layer 16b to a depth that reaches the surface of the electrode layer 16b.

The second display electrode 20 shown in FIG. 5 includes a glass substrate 21, transparent ITO electrode layers 22a to 22c and an 8i02 insulating layer 26 sequentially deposited on this substrate 21, and electrode layers 22a to 22. c are insulated from each other by grooves 24.2-5. Insulating layer 2 deposited on electrode layer 22b
Pattern B with letters above 6 was formed in the same manner as in Example 1, and was made of a Prussian blue thin film obtained by electrolytic synthesis. Each display electrode 14, 20f is fixed (with an adhesive 26 and a spacer 27) to form a cell, as shown in FIG. An electrolytic solution 28 having the same composition as in Example 1 is sealed in this cell to form an ROD. In this EOD, each of the electrode layers of the display electrodes 14 and 20 shown in FIGS. is electrically connected to the working electrode,
The electrode layer 22c is provided to serve as a reference electrode.

In FIG. 6, the first display electrode 14 and the second display electrode 20
are shown in cross-sectional views taken along the line vi-Vl in FIGS. 4 and 5, respectively, where numerals 60 to 66 correspond to pattern A, and numerals 34 and 65 correspond to turn B.

In the EOD configured in this way, when no potential is applied to the working electrode, that is, in a state of natural potential, pattern B is always displayed in blue, and when the potential E of the working electrode is changed, as in Example 1, The next conductive potential E corresponds to the color of the pattern to perform multicolor display.

E≦-〇, 5V vs, 880B Red-purple (display of l-8TOPJ of putter yA) 10, 35V≦E≦-0,05V Transparent (no display) 0
．． 1V≦Evs, 880B blue (Putter yB's "GO"
In addition to the EC material used in each of the above examples, the EOD of the present invention contains FF4(M"(ON
) 6) Ruthenium purple (
, osmium purple (purple) where M" = Os" (however, the colors written in parentheses represent the colors that each substance fixed on the electrode shows on the electrode in a state of natural potential) In addition, the reduced EC substances include methyl viologen (purple), cyanoviologne (green), p-benzoquinone (yellowish brown), and benzyl viologen (purple) (however, the colors in parentheses indicate each substance in the reduced state) ) can be used.

Further, as the reduced mEC substance, a polymer of the above-mentioned substances, a polyion LAMPLEX such as polyxyl viologen-sodium polysulfonate, or the like may be used by forming a film on the electrode surface.

Effects of the Invention In the multicolor EOD according to the present invention, since the aqueous conductive layer contains an oxidized EC substance and a reduced EC substance, both can be changed by changing the potential of the electrode for applying an electric field to the conductive layer. The EC substances can be colored separately, and different information can be displayed in different colors.

In addition, by using an EC material that is colored when the electrode is in a state of natural potential and an EC material that is colorless as the EC material, the necessary colored display can always be made even without applying a voltage. You can do it like this.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a display electrode in the first embodiment of the present invention, FIG. 2 is a longitudinal cross-sectional view of the EOD in the first embodiment, and FIG. 6 is a cyclic voltage of the BOD in the first embodiment. Moda 2
4 and 5 are perspective views of the first and second display electrodes, respectively, in a second embodiment of the present invention, and FIG. 6 is a longitudinal sectional view of the gOD of the second embodiment. In addition, in the symbols used in the drawings, 1...
...Display electrode 2%8.15.21...Glass substrate 3.9.1
6a-16c, 22a-22c...electrode layer 4.7.
23... Insulating layer 5.6, A, B... Pattern 7... Reference electrode 12... Counter electrode 16.28... Electrolyte 14...First display electrode 20...'Second display electrode. Agent Masaru Ueya Yoshio Tsuneko (Voluntary) ``Procedural amendment dated June 6, 1980'' Director General of the Japan Patent Office 1. Indication of the case Patent Application No. 77890 of 1988 21" 8 Multicolor illustration (218) Sony Corporation 6, number of inventions increased by amendment 11), r Fea (Fe (
KBFe4 (re (ON)a)
s J color correction-jru. (2), page 8, line 20, “vs, 880E J
Delete wo. (3), page 9, line 3, "vs, 5HOE J')" is deleted.

Claims (1)

[Claims] A multicolor display device comprising a conductive layer made of a substance that develops color through oxidation, a substance that develops color through reduction, and an aqueous electrolyte solution, and an electrode connected to a voltage source to apply an electric field to the conductive layer. .