JPS62215682A - Electrochromic displayer - Google Patents

Abstract

PURPOSE:The titled displayer capable of showing fine pattern of improved contrast by change in color of thin film, by impressing voltage between a display electrode having a thin film of a specific substance deposited by vacuum metallizing and an opposing electrode set through an electrolytic layer. CONSTITUTION:Voltage is impressed between a display electrode 8 having a thin film 7 of fluorenone (derivative) (e.g. 2,4,7-trinitro-9-fluorenone, etc.) deposited by vacuum metallizing and an opposing electrode 9 set through a layer 16 of an electrolyte (e.g. polystyrenesulfone, etc.). EFFECT:The aimed device of ultrathin type can be produced and letter, etc., can be clearly shown on a white or transparent substrate.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrochromic display device (hereinafter referred to as ECD).
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[Summary of the invention]

The present invention is an IECD in which a fine pattern with good contrast can be displayed by using a display electrode on which a thin film of a specific organic compound is formed by vacuum evaporation.

[Conventional technology]

Various ECDs that utilize the phenomenon of reversible change in color tone (electrochromism) by electrical oxidation-reduction have been developed and put into practical use.

Such ECDs include, for example, solution type ECDs and polymer coating type ECDs. In a solution-type ECD, an electrolyte solution containing a substance exhibiting electrochromism (hereinafter referred to as an EC substance) is sealed in a cell equipped with a display electrode, and the solution itself develops or changes color when electricity is applied between the electrodes. Alternatively, the display is performed by depositing a discolored substance on the electrode. On the other hand, in a polymer coating type ECD, display is performed by forming a pattern in which a polymer coated on electrodes is colored or changed in color by applying electricity between the electrodes.

[Problem that the invention seeks to solve]

The above-mentioned solution-type ECD has the disadvantage that when the solution itself develops or changes color, the contrast is low and the display tends to flow.

On the other hand, a polymer pendant type and a polyion complex type are considered as the EC material for the polymer-coated ECD described in ";".

Polymer pendant type EC materials are made of polymers with electrochromic functions in their side chains, and have the disadvantage that they are difficult to synthesize. Furthermore, the polyion complex type EC substance has a drawback that the EC substance has a weak trapping force and is easily released from the membrane.

In view of the above-mentioned problems, the present invention provides a novel ECD whose structure is completely different from that of conventional ECDs.

[Means for solving problems]

The present invention includes a display electrode on which a thin film of fluorenone or a derivative thereof is deposited by vacuum deposition, and a counter electrode disposed with an electrolyte layer interposed therebetween, and a voltage is applied between the display electrode and the counter electrode. The present invention relates to an ECD configured to change the color of the thin film by changing the color of the thin film.

The display electrode of the present invention is made of tin oxide, indium i-ride-tin oxide (hereinafter referred to as I-tin oxide) on a substrate made of glass, plastic, etc.
It can be obtained by depositing a transparent electrode thin film made of fluorenone (hereinafter referred to as TO) or the like, and then depositing a thin film made of fluorenone or a derivative thereof on this Wi film using a vacuum evaporation method.

2,4.7-) Leetrow-9-fluorenone, shown as 9-fluorenonedene) malonitrile.

The counter electrode of the present invention can be obtained by depositing an electrode thin film made of a conductor on a substrate made of glass, plastic, or the like.

At least one side of each substrate and each electrode thin film of the display electrode and the counter electrode is transparent so that the display due to color development of the ECD substance can be observed.

As the electrolyte of the present invention, an aqueous solution such as KBr, KCl, KNO3 or a solid polymer electrolyte such as polystyrene sulfonic acid can be used.

The thin film made of the above-mentioned fluorenone or its derivative is colorless and transparent in a non-reduced state, but it is reduced by applying electricity between the electrodes to develop a color such as red or green and is stable in air. Furthermore, this thin film can be reoxidized to return to a colorless and transparent state by applying a reverse voltage. In addition, this thin film is fixed to the electrode and develops color, and the electrolyte does not develop color, so
The contrast of the display is good and the display does not flow. Therefore, fine patterned display becomes possible.

〔Example〕

Embodiments of the display device of the present invention will be described below with reference to the drawings.

EXAMPLE 1 In this example, an example of the ECD of the present invention will be explained while showing an outline of its manufacturing method.

First, a photoresist layer 3 is formed on a transparent ITO electrode layer 2 adhered to a glass substrate 1 (FIG. 1A), exposed to ultraviolet rays through a negative pattern mask 4, and then formed to a thickness of 3. An insulator SiO□ film 5 was formed by vacuum evaporation (Fig. 1B), and then the photoresist was peeled off to form a patterned SiO film 6 on the ITO electrode layer 2 (Fig. 1C). figure). Next, a thin film 7 made of 2.4.7-)dinitro-9-fluorenone and having a thickness of about 2.800 mm (measured with an interference microscope) was formed as an EC material thin film to form a display electrode 8 (Fig. 1D). ). The thin film 7 was formed by placing 2.4.7-)dinitro-9-fluorenone powder in a tungsten boat, applying a 25A resistance heating current for about 20 minutes, and using a vacuum evaporation method at a vacuum level of 1 x 10-5w11g. This was done by The counter electrode 9 was formed by depositing a transparent ITO electrode layer 11 on a glass substrate 10, and the glass substrate 10 was provided with a through hole 12 and a supply pipe 13 communicating with the through hole (FIG. 1D). The display electrode 8 and the counter electrode 9 were crimped and fixed using a spacer 14 and an adhesive 15 arranged as shown in FIG. 1D. Next, the supply pipe 13
From 0.1MK1! The aqueous electrolyte 16 was supplied, the supply pipe 13 was closed, and the ECD shown in FIG. 2 was obtained.

Next, IMKC1 of the EC material thin film used in the above 0ECD
The absorbance in the colored state B (reddish purple) and the decolored state in an aqueous solution was measured, and the transmittance was determined from the results to obtain the graph shown in FIG.

In the actual suitable concentration vacuum evaporation method, 2,4,5,7-tetranitro-
Example 0ECD was obtained in the same manner as in Example 1 except that 9-fluorenone was used and the resistance heating current was 3OA.

This ECD exhibited a reddish-purple color in a colored state.

Next, the transmittance of the EC material thin film used in this ECD was determined in the same manner as in Example 1, and the graph shown in FIG. 4 was obtained. On the other hand, I.M.
A platinum electrode was used as the counter electrode in the KC1 aqueous solution, an Ag-AgC1 electrode was used as the reference electrode, and the scanning speed was 10.
A cyclic portammogram shown in FIG. 5 was obtained under the conditions of mV/sec.

In the 111 vacuum evaporation method, (2,4,7-)dinitro-9=
Using malonitrile (fluorenylidene), the degree of vacuum was 5.
An ECD of this example was obtained in the same manner as in Example 1 except that X was set to 10-' mmHg. This ECD exhibited a green color in a colored state.

Next, the transmittance of the EC material thin film used in this ECD was determined in the same manner as in Example 1, and the graph shown in FIG. 6 was obtained. On the other hand, the seventh
The cyclic portammogram shown in the figure was obtained in the same manner as in Example 2.

All of the ECDs of Example 0 described above had good contrast during color development and were capable of displaying fine patterns.

〔Effect of the invention〕

In the ECD of the present invention, fluorenone or a derivative thereof deposited on the display electrode of the ECD develops color to perform display.

Therefore, there is no display flow, a display with good contrast is possible, and a fine pattern display is possible. Furthermore, since the thin film is formed by vacuum evaporation, electrochromism can be expressed in a thin film state, making it possible to manufacture an ultra-thin ECD.

Furthermore, according to the ECD of the present invention, it is possible to make characters etc. stand out on a white background or a transparent substrate,
On the other hand, since the thin film made of fluorenone or its derivatives is transparent, it can be used as a transmission type ECD, which widens the range of applications.

[Brief explanation of drawings]

1A to 1D are cross-sectional views for explaining one manufacturing method of the ECD of the present invention, FIG. 2 is a cross-sectional view of the ECD of the embodiment, and FIG. 3 is the EC material thin film of the first embodiment of the present invention. FIG. 4 is a graph of the transmission spectrum of the EC material thin film of the second embodiment, FIG. 5 is a cyclic portammogram of the display electrode of the second embodiment, and FIG. 6 is a graph of the third embodiment. A graph of the transmission spectrum of the EC material thin film of the example, and FIG. 7 is a cyclic portamogram of the display electrode of the third example. In addition, in the symbols used in the drawings, 7-・-・・-
−−−−・−・−・−Thin film 8−・−1−−−−−−−
・−・−・−Display electrode 9・・−−−−−−−−・−・
-・-・One counter electrode 16・----111---
......--It is an electrolyte.

Claims (1)

[Claims] The display electrode includes a display electrode on which a thin film of fluorenone or a derivative thereof is deposited by vacuum evaporation, and a counter electrode disposed with an electrolyte layer interposed therebetween, and by applying a voltage between the display electrode and the counter electrode, the An electrochromic display device configured to change the color of a thin film.