JPS61114227A - electrochromic display element - Google Patents

Abstract

PURPOSE:To enable display density to be enhanced, and one panel to display multicolor by forming plural display electrodes on the inside one of a pair of base plates, and an opposite electrode on the inside of the other base plate, and sealing an electrochromic soln. or an electrolyte into each section of the display electrodes separated with partition walls. CONSTITUTION:The plural display electrodes 3 are formed on the inside of one 1 of the base plates 1, 2 made of glass, and the opposite electrode 4 is formed on the inside of the other base plate 2. Both plates 1, 2 provided with the electrodes 3, 4 are sealed with a sealing agent 5, such as an epoxy resin or a glass of low m.p., at the outer border between the plate 1 and the electrode 4. In the case of the 3 electrodes 3, partition walls 7 made of an epoxy resin or low m.p. glass or the like is formed to divide the inside space between the plate 1 and the electrode 4 into the 3 display electrodes 3 of sections A, B, and C. The electrochromic soln. or electrolyte 6 is sealed into each section A, B, and C to keep each section out of contact from each other and to equalize each display electrode 3 in area ratio to each opposite electrode 4 each section.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to electrochromic display elements.

Conventional Structure and Problems Liquid crystal and electrochromic display elements are well known as light-receiving display elements. Among these, electrochromic display elements are characterized by no viewing angle dependence and clear colors. This conventional electrochromic display element has a pair of glass substrates 1 and 2 as shown in FIG.
A plurality of display electrodes 3 are provided on the inside of one substrate 1, and a counter electrode 4 is provided on the inside of the other substrate 2. A sealing material 6 is provided between the outer edges of the substrate 1.2 provided with these electrodes 3.4, and an electrochromic solution 6 is sealed in the inner space.

When a DC voltage is applied between the display electrode 3 and the counter electrode 4 so that the display electrode 3 becomes positive, color develops under the display electrode 3 to which 5 voltages are applied, and 1 display is obtained. As the electrochromic solution 6, an inorganic solution and an organic solution are used. Among the inorganic materials, WO3 is the most well-known and has relatively stable characteristics, but the display life is short, there is color unevenness between the display segments, and the display is blue-ish. There are drawbacks such as. As organic substances, dyes such as viologen, anthraquinone, pyrazoline, and styryl-like compounds are known.

By using this organic dye, more vivid colors and a greater variety of colors can be obtained. However, the display life is short,
The counter electrode 40 at 0 has disadvantages such as slow response speed.
Although the area is constant, it is not necessary to apply a voltage to all of the plurality of display electrodes 3, so depending on the total area of the display electrodes 3 to which a voltage is applied, The area ratio with the electrode 4 is different. For example, when a positive voltage is applied to the three display electrodes 3 at the same time with respect to the counter electrode 4, and when a positive voltage is applied to one or two of the three display electrodes 3, the display electrode 3 Electrode 4
The area ratio changes. FIG. 2 shows the changes in color density when the area ratio between the display electrode 3 and the counter electrode 4 is changed. As the area ratio increases from 1:39.1:260, etc. , 1. II. As is clear from the line indicated by drunkenness, the saturation concentration becomes higher. Conversely, as the area ratio decreases, the saturation concentration decreases. Therefore, when a plurality of display electrodes 3 are provided as described above, the area of the display electrodes 3 differs depending on the number of display electrodes, so the saturation concentration also becomes non-uniform depending on the area of each display electrode 3, and the display density becomes non-uniform. It has some drawbacks.

Also, since there is only one electrochromic solution 6 in the panel, only -colors can be displayed.

OBJECTS OF THE INVENTION It is an object of the present invention to provide an electrochromic display element that can make the display density uniform and can also display multiple colors on the panel.

Structure of the Invention In order to achieve the above object, the present invention provides a pair of substrates, at least one of which is transparent, a plurality of display electrodes provided inside one substrate, and a plurality of display electrodes provided inside the other substrate. It is characterized in that it has a counter electrode, a separation wall that separates the display electrode into each region, and an electrochromic solution or an electrolytic solution sealed in each region.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. As shown in FIG. 3, a plurality of display electrodes 3 are provided inside one of the glass substrates 1.2,
A counter electrode 4 is provided inside the other substrate 2 .

Between the outer edges of the substrates 1 and 2 provided with the electrodes 3 and 4, the space between the substrate 1 and the electrodes 4 is sealed with a sealing material 5 made of epoxy resin, low melting point glass, or the like. In the case where there are three display electrodes 3 as in the illustrated example, a separation wall 7 made of epoxy resin, low melting point glass, etc. is provided between the substrate 1 and the electrodes 4 to separate each display electrode 3. The space is divided into three areas A, B, and C. An electrochromic solution or an electrolytic solution 6 is sealed in each region A, B, and C separated by this separation wall 7, and each region A, B
, C are not in contact with each other, and the area ratio of the display electrode 3 and the counter electrode 4 in each electrochromic region is equal to 6.
, -1.

As described above, when the three regions A, B, and C are fixed by the separation wall 7 and a constant voltage is applied, the same saturation concentration can always be obtained. Furthermore, since the area ratios of the display electrode 3 and the counter electrode 4 are equal in the three regions A, B, and C, the same display density can be obtained in each region. Also A, B.

By filling each area of C with electrochromic solutions or electrolyte solutions 6 of different colors, it is possible to achieve multiple colors in one panel.

Note that the counter electrode 4 may be continuous as a single sheet, or may be separated into each region A, B, and C.

As a specific example of the above embodiment, glass substrates 1 and 2
In 20 a was deposited thereon to form a display electrode 3 and a counter electrode 4 . The sealing material 6 and the separation wall 7 were formed of low melting point glass. The distance between the display electrode 3 and the counter electrode 4 was set to about 25 μm. As the electrochromic solution 6, 3, which is one of the dyes of styryl-like compounds, is used.
, 3-dimethyl-2-(P-dimethylaminostyryl)
Indolino[2.-b]oxazoline was used, which was dissolved in the solvent acetonate along with tetrabutylammonium perchlorate as a supporting electrolyte. The area ratio between the display electrode 3 and the counter electrode 4 was set to 1:9.

Therefore, when +1.2■ is applied to the display electrode 3 with respect to the counter electrode 4, the saturation concentration is approximately 0.2 for ○, D, and
The color density of each region A, B, and C was always uniform. Furthermore, when a constant voltage was applied to each display electrode 3, all display saturation concentrations could always be made uniform.

Also, the substrates 1 and 2, the display electrode 3, the counter electrode 4, the sealing material 6
The separation wall 7 is formed in the same manner as in the above specific example, and the electrochromic solution 6 is 3,3-dimethyl-2-(P
-dimethylaminostyryl) indolino [2.1-b]
Oxazoline (abbreviation: IRPDM), a,3-dimethyl-2-(P-dimethylaminocinnamylidenevinyl)indolino[2.1-b]oxazoline (abbreviation: I4RP)
DM), 3,3-dimethyl-5-methylsulfonyl-2
-(p-dimethylaminocinnamylidenevinyl)indolino[2.1-b]oxazoline (abbreviation: SMI4RP)
DM) for each area A using three types of dyes.

B and C were individually sealed.

When a positive voltage is applied to the display electrode 3 with respect to the counter electrode 4, the maximum absorption wavelength is 647 nm for IRPDM and 647 nm for I4R.
PDM had a wavelength of 612 nm, and SMI4RPDM had a wavelength of 654 nm, and elements of three different colors were obtained in one panel.

Effects of the Invention As is clear from the above explanation, according to the present invention, a plurality of display electrodes are provided inside one of the pair of substrates,
A counter electrode is provided inside the other substrate, the display electrodes are separated by a separation wall, and an electrochromic solution or an electrolytic solution is sealed in each separated region. Therefore, the display density can be made uniform, and different colored electrochromic solutions can be used in each region, thereby making it possible to perform multicolor display on the panel.

[Brief explanation of the drawing]

9 - Figure 1 is a cross-sectional view of a conventional electrochromic display element, Figure 2 is a diagram showing the rise in display density and changes in saturation concentration depending on the ratio of display electrode area to counter electrode area, and Figure 3 is a diagram showing changes in display density and saturation concentration depending on the ratio of display electrode area to counter electrode area. FIG. 1 is a cross-sectional view showing one embodiment of an electrochromic display element of the present invention.

Claims (3)

[Claims] (1) A pair of substrates, at least one of which is transparent, a plurality of display electrodes provided inside one substrate, a counter electrode provided inside the other substrate, and the display electrodes arranged in each region. An electrochromic display element characterized by having a separation wall for separation and an electrochromic solution or electrolyte sealed in each region. (2) The electrochromic display element according to claim 1, wherein the ratio of the area of the display electrode and the area of the counter electrode in each region is equal. (3) The electrochromic display element according to claim 1, wherein the electrochromic solution or electrolytic solution sealed in each region develops a different color.