JPS58107518A - Production of electrochromic display element - Google Patents

Abstract

PURPOSE:To ensure a display of a long lifetime and high durability, by forming previously an insulator layer on the lower electrode of a substrate of a full solid state EC display element and therefore preventing a short circuit although there occurs a contact between the upper and lower electrodes due to the breakdown of contour in case the upper electrode pattern is vapor-deposited. CONSTITUTION:A full solid state EC display element is formed by laminating a lower electrode A, an ion insulator layer Z, a reductive EC layer B, an oxidative EC layer D, an ion conductive layer C and an upper electrode E on a substrate S. In this case, the layer Z is vapor-deposited with a mask on the electrode A to assure the insulation to the electrode E. As the layer Z is provided at the region where a contact may occur between the electrodes A and A owing to the breakdown of the contour when the pattern of the electrode E is vapor-deposited with a mask, no short circuit occurs. As a result, the durability is improved for an EC display.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a display panel using an electrochemical coloring/decoloring phenomenon, that is, an electrochromic (hereinafter abbreviated as EC) phenomenon.

It has been more than 15 years since we attempted to create display elements that repeatedly change color and fade by applying and removing voltage using EC substances that exhibit this phenomenon, and to use these display elements to display numbers on clocks and computers. It has been done before. For example, a transparent electrode film (cathode), a tungsten trioxide thin film, an insulating film such as silicon dioxide, and an electrode film (anode) are placed on a glass substrate.
All-solid-state EC display elements are already known, which are formed by sequentially laminating the following layers. When a voltage is applied to this display element, tungsten trioxide (WOs) Ill is colored blue. Thereafter, when a reverse voltage is applied to this display element, the blue color of the WO3 thin film disappears and it becomes colorless. Although the mechanism of this coloring and decoloring has not been elucidated in detail, it is known that a trace amount of water contained in the WO, thin film, and insulating film controls the coloring and decoloring of the WO. The reaction formula for coloring is estimated as follows.

H+ 0- H+ 0H- (WOs film=cathode side) (Insulating film=anode side) 20H-□ 1(, o + -!-0, ↑+e- Therefore, the drawbacks of such a display element are ■ During the coloring reaction,
The water content is consumed by an undesirable side reaction of oxygen gas generation, and (1) water is not produced by the reverse decoloring reaction, so water needs to be replenished from the atmosphere for repeated coloring. Particularly because of the latter reason (2), this type of display element has the drawback that the reproducibility of coloring is affected by moisture in the atmosphere.

Recently, the same amount of water as consumed by the coloring reaction is produced by the decoloring reaction, and therefore coloring and decoloring can be repeated without the need for water supply from the outside world, and the coloring can be repeated repeatedly. An all-solid-state EC display element whose concentration is not affected by the outside world has been proposed (see Japanese Patent Laid-Open No. 73749/1983). This display element is basically formed by sequentially laminating a transparent electrode, an electrolytic reduction color forming thin film such as W OS, an electrolytic oxidizing thin film such as Cr20B, and a counter electrode. According to the disclosure in the above-mentioned publication, when the voltage is removed after being colored by applying a voltage, a phenomenon in which the coloring gradually disappears due to spontaneous discharge is observed, and the property that the coloring is preserved even after the voltage is removed (this is called meso In order to provide this display element with the desired properties (referred to as "transparent"), it is necessary to provide an insulating film, such as a thin film of silicon dioxide, magnesium heptadide, etc., at any position between the transparent electrode and the counter electrode. . According to the inventor's speculation, this insulating film is electronically insulating, but it is ionic conductive, allowing free movement of protons (H) and doroxy ions (OH-), and is also insulating. The membrane must be provided between the electrolytic reduction color forming thin film and the electrolytic oxidizing thin film.

Incidentally, in such an all-solid-state EC display element, each layer must be made thin, so a thin film forming technique such as vacuum evaporation is used to form the layers.

The electrode layer must also be made thinner in order to make the entire device thinner and to increase transparency. Therefore, if the lower electrode pattern and the upper electrode pattern are made to overlap completely, it becomes impossible to draw out the lower electrode. Therefore, the lower electrode pattern and the upper electrode pattern are
It is necessary to shift it somewhat, so that at least a part of the outer line of the upper electrode pattern crosses the lower electrode pattern.

To deposit the upper electrode in a specific pattern, one-sphere deposition is easy and desirable to use, but mask deposition tends to distort the outline and spread out (also referred to as blurring) from the predetermined position. This can have the unfortunate result of unexpected contact (short circuit) between the lower and upper electrodes at certain positions.

Therefore, an object of the present invention is to improve the manufacturing method in which the upper electrode is in contact with the upper electrode when manufacturing an EC display element by mask vapor deposition of such an upper electrode pattern.

Therefore, in the method of manufacturing an all-solid-state electric TSI display element, the present invention provides a method for manufacturing an all-solid-state electric TSI display element. Provided is a method characterized in that an insulating layer is formed on an electrode, and an upper electrode pattern is deposited using a mask.

Next, the present invention will be specifically explained by examples with reference to the drawings.

Figures 1 (1) to (8) are plan views, and figures (1 to (7)
") is a cross-sectional end view taken along the line X-Y in FIGS. (1) to (7).

First, a substrate (S) such as a glass plate, a ceramic plate, or a hard plastic plate is prepared, and a lower electrode (N) is vacuum-deposited on it as shown in Figure (1).The lower electrode can also be patterned. For this purpose, the lower electrode pattern may be formed by a mask vapor deposition method or by a method in which after uniform vapor deposition over the entire surface, a resist layer is formed on the required portion and the exposed electrode is removed by etching.

As the lower electrode material, for example, Snow, indium oxide, ITO (indium oxide mixed with about 5'1 of 5nO1), copper iodide, gold, etc. are used.

A thickness of 0.01 to 0.5 μm is sufficient for this electrode layer (A).

In FIG. 1(2), the planned upper electrode pattern is indicated by diagonal lines.

Next, in accordance with the characteristics of the present invention, when mask-depositing the upper electrode pattern shown in FIG.
)), and an electronic and ionic insulator layer (indicated by fine diagonal lines in Methods for patterning the (Z) layer include mask method, photo-etching method,
A method using photoresist, a screen printing method, etc. are used.

The thickness of the (Z) layer is preferably as thin as possible as long as the purpose of insulation is achieved, but 100 to 500 μm is usually sufficient.

Insulator layers 0) that can be used include, for example, silicon oxide 5top, titanium oxide TlO2, zircon oxide Zr
O snow, bismuth oxide Bi2O3, hafnium oxide HfO
2. Tantalum pentoxide 7'a20@% yttrium oxide YtOs.

Aluminum oxide Al2O3% magnesium oxide MgOs
Cerium oxide CeO2, chromium oxide Cr! 03, Niobium oxide N~03, Calcium oxide CaO, Antimony oxide 5-03, Magnesium fluoride MgF1.7 Lithium fluoride F, Calcium fluoride CaFx, Neodymium fluoride NdF, Cerium fluoride CeF31 Lanthanum fluoride La5s, Examples include silicon nitride Si3N4, Evokin resin, EVA, resist, parylene (a type of xylene resin), and various other polymer insulating materials.

Next, as shown in Figure (4)% (4°), two large and small triangular reducing EC layers (B) or oxidizing EC layers (B) are deposited using a mask. For patterning, instead of mask deposition, a photolithography method that produces an accurate pattern can also be used. These triangles become the display part (coloring/decoloring part) of the EC display element. The thickness of the (4 and 4) layers is usually 0. O
O1 to several μm is sufficient.

Here, examples of the reducible EC layer (B) include tungsten oxide, molybdenum oxide, or a mixture thereof. These exemplified substances are colored by electrolytic reduction reaction.

On the other hand, examples of the oxidizing EC layer (c) include nickel hydroxide, iridium hydroxide, ruthenium hydroxide, chromium hydroxide, pdium hydroxide, and the like.

Since it is difficult to vacuum-deposit these hydroxides directly, the corresponding metal is first vapor-deposited, and then the hydroxides (EC substances) are anodized in an acid or alkaline aqueous solution after vapor deposition or buttering. or (E
) After laminating the upper electrode, it is anodized by applying an alternating current voltage in the atmosphere to convert it into hydroxide (EC material).

Next, in a region that completely covers layer (B) or (D) of the display part and does not contact the lower electrode,
), the ion conductor layer (C) was deposited using a mask.

This ionic conductor layer ←) contains a small amount of water and exhibits ionic conductivity, for example, in an oxidation tank k (Ta
gOs), niobium oxide (NbHiroOs), zirconium oxide (Zr(%)), titanium oxide (Ti01),
Hafnium oxide (Hf02), yttrium oxide (Y!
03), oxidation rank y (La*Os), silicon oxide (
Inorganic materials such as Stow), magnesium fluoride, and cerium phosphate are used. These materials are insulators for electrons, but good conductors for proton (H) and hydroxy ions. Ionic conductor layer (
The film thickness of C) is selected from 0.001 to 100 μm in consideration of display memory time and transparency.

Next, the remaining one of the (B) layer or the υ) layer is shown in Figure (6).
), (mask deposition as shown in 6).

Next, as shown in Figures (7) and (7'), the upper electrode (E)
is deposited using a mask. However, according to the present invention, since an insulating layer is formed in advance in the area where contact with the lower electrode is expected, even if the predetermined contour line collapses and spreads as a result of mask deposition, the upper electrode will remain intact. Direct contact with the bottom electrode (
The upper electrode, which does not cause short circuits, is made of the same materials as the lower electrode that can be deposited, such as IntOs, iodized steel, and gold.

Next, as shown in FIG. 1 (8), lead wires (L+, L) are attached to both electrodes.

A shielding protection plate (p) having a transparent window (6) as shown in FIG. 2 is placed over the display element thus obtained through a transparent sealing resin (9) such as epoxy resin. Glue to. The results are shown in FIG. 3 (cross-sectional view).

When a voltage of about 1 to 2 volts is applied to the display element decorated in this way through the lead wire Lh14, the element becomes 100 volts.
~200 m5ec, for example, is colored blue. This colored state is shown in FIG. 4 (plan view), and the colored portion is a triangular mesh portion. The colored state is maintained even if the voltage application is stopped.

Next, when a reverse voltage of about 0.5 to 2 ports is applied,
The element loses its color in about 50 to 100 m5ec and returns to its original colorless and transparent state (see Fig. 5).

According to the present invention, when the upper electrode pattern is deposited using a mask, an insulating layer is provided in advance on the lower electrode in areas where the contour is distorted and comes into contact with the lower electrode, or where there is a risk of contacting the lower electrode. Even if the pattern is formed by a simple method of mask vapor deposition, there will be no short circuit with the lower electrode.

[Brief explanation of the drawing]

FIG. 1 is for explaining the manufacturing method of an EC display element according to an embodiment of the present invention, and FIGS. (1) to (8) are plan views, and FIGS. 〜(7)ノx −Y
FIG. FIG. 2 is a plan view of a protection plate that may be placed on the EC display element for protection and decoration, and FIG.
FIG. 3 is a cross-sectional end view of a structure in which the protection plate of FIG. 2 is adhered to two objects via a sealing resin. FIG. 4 is a plan view of the EC display element shown in FIG. 3, showing a colored state, and FIG. 5 showing a similarly decolored state. [Explanation of symbols of main parts] S・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・Board ^・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・ Lower electrode Z・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
Insulator layer B・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・Reducing EC layer C・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
Ion conductor layer D・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・ Oxidizing EC layer E・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・ Upper electrode P・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・ Protective plate W・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・ Transparent window R・・・・・・・・・・・・・・・・・・・・・
...... Sealing resin L1% t, ......
・・・・・・・・・・・・・・・ Lead wire applicant
Takao Watanabe, Agent for Nippon Kogaku Kogyo Co., Ltd. / +-IA Diagram (1) (1') (2); A-2 Figure 3 Figure 74 Figure 5 Procedure Amendment (Spontaneous) 1982 May 120, 2006, Commissioner of the Japan Patent Office Shima 1) Haruki Tono1, Indication of the case 1982 Patent Application No. 2067312, Name of the invention Method for manufacturing electrochromic display elements 3, Relationship with the amended person case Patent publication Client: Nippon Kogaku Kogyo Co., Ltd. 4, 3-2-3 Marunouchi, Chiyoda-ku, Tokyo (411), Agent: 1-6-3 Nishi-Oi, Honbunagawa-ku, Tokyo 140
Contents of amendment in Column 6 “Detailed Description of the Invention” (1) “(1) to (8)” in page 6, line 5 of the specification have been changed to [
1a) ~ (8a) j, and the accompanying [(1°) ~ (7
')J is corrected as It(1tl)~(7't))j. (2) Change “(1) to (7)” on page 6, line 6 of the same page to lr(
1a") to (7a), j. (3) "Figures (1), (1') on page 6, lines 8 to 9.
Correct J to Figure 1 (1a), (1b), and j. (4) "Figure 1 (2)" in the 1st line and 3rd to 4th lines of page 7 is corrected to ``Figure (2a).'' (5) Page 7, line 6 [Figure (3), (3° moon,
1 (6a), (3b1). (6) "Figure (4), (4')J" on page 8, line 11.
should be corrected as ``Figure (4a), (,41)) J. (7) Figure 1 (5), (5') on the 6th line from the bottom of page 9
) J should be corrected as ■ (5a), (5b). (8) “Figure (6),” on page 101, line 10y11,
(6°)" should be corrected to "(6a), (6b)" in Figure 1. (9) On page 10, line 12, correct [Figures (7) and (7') J to 1 (7a) and (7b).'' 01 "Figure 1 (8)" in the second line of page 11 is corrected as "Figure 1 (8a), II. Procedural Amendment (Method) 1, Indication of Case 1982 Patent Application No. 206731 2, Name of the invention: Method for manufacturing electrochromic display elements 3, Relationship with the amended party case Patent applicant: Nippon Kogaku Kogyo Co., Ltd., 3-2-3 Marunouchi, Chiyoda-ku, Tokyo (411) 4; Agent Address: 1-6-3-5 Nishi-Oi, Honbunagawa-ku, Tokyo 140 Date of Amendment Order: 7 - April 9, 1980 (Shipping date: April 27, 1980)
6. Subject of amendment: O Description, "Brief explanation of drawings" column 0 Drawing (1) "Drawings (1) to (Xun)" on page 12, line 7 of the specification
is corrected as Figure 1 (1a) to (8a)J. (2) "Figures (1') to (7') on page 12, line 8.
) J. Figure 1 (1b)-(7kl) Corrected as J. (゛), page 127, line I, 0 “Figures 0) to (7)”
Figure 1 (1a) to (71J) are corrected. (4) Figure 1 (7'
) J. rFigure 1 (7m)) Correct as J. (!9 Correct the attached drawings in Figure 1 and Figure 1B. a List of attached documents (1) Corrected Figure 1 and Figure 1B...
1 letter; +IA (1α) (2cL) Figure (1b) ) (5shi) (,4b) αkoα]

Claims (1)

[Claims] In the manufacturing method of an all-solid-state electrocoumic display element, an insulator is applied in advance on the lower electrode in areas where the contour of the upper electrode pattern is distorted and comes into contact with the lower electrode, or where there is a risk of contacting the lower electrode when the upper electrode pattern is vapor-deposited using a mask. A method characterized in that a layer is formed in advance, and the electrode pattern is deposited using a mask.