JPS6365927B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an electrochromic display device (hereinafter abbreviated as ECD) that utilizes electrochemical coloring and erasing reactions. Generally consists of a display electrode, a counter electrode, and an electrolyte.
When an electrolyte is injected into an ECD at room temperature, when used at high temperatures, the pressure inside the ECD increases due to thermal expansion of the electrolyte, causing damage. Therefore, a method has been reported in which bubbles with a volume ratio of about 10% are installed in the cell, taking into account the thermal expansion of the electrolytic solution. Although this method does not cause damage when used in a high temperature atmosphere, air bubbles are always present in the cells. Moreover, when used in a low-temperature atmosphere, the electrolyte contracts and becomes even larger bubbles. Note that even if air bubbles exist in the cell, there is no problem as long as they do not appear on the display electrode, but if vibration is applied or the cell falls over, bubbles can easily move to any position, so they will definitely not appear on the display electrode side. There is no guarantee that it won't happen. If it appears on the display pole side, the display becomes difficult to see and the product value decreases. Placing air bubbles in the cells in this way is not the best way to prevent damage. In view of these problems, the present invention provides an ECD that prevents damage due to thermal expansion of the electrolyte when the ECD is used at high temperatures, and does not generate bubbles when used at room or even low temperatures. and
It is characterized by having an elastic body installed inside. Now, if an electrolyte is injected into an ECD with a reversible elastic body sealed at room temperature and sealed, and left at a high temperature, the electrolyte will expand as the temperature rises.
The pressure inside the ECD also begins to rise. Pressure acts equally on the surface in contact with the electrolyte. If the elastic body of the present invention, which easily contracts even at low pressure, is present therein, the elastic body will contract and absorb the pressure. Therefore, the pressure acting on other surfaces decreases.
For example, in the case of an electrolytic solution in which lithium perchlorate is dissolved in propylene carbonate, if the volume of the electrolytic solution at 20°C is 1, then at 75°C it becomes 1.04. follow
Any elastic material that shrinks by 0.04 at 75°C will suffice.
When the electrolyte expands in this manner, the elastic body contracts in proportion to the rate of expansion, thereby preventing damage to the ECD. Even at low temperatures near room temperature, the elastic body expands in accordance with the volume reduction of the electrolytic solution, and unnecessary movement of the elastic body does not occur. If bubbles are allowed to exist for use in a high-temperature atmosphere as in the past, bubbles or cavities will be generated due to pressure drop at low temperatures, and these bubbles or cavities will occur at arbitrary positions within the ECD, which is an inconvenience. There is.
In the present invention, a predetermined elastic body is installed inside, so that unnecessary bubbles or cavities are not generated, and the elastic body at a predetermined position can perform contraction/expansion actions. Hereinafter, an ECD according to an embodiment of the present invention will be explained. The figure shows an ECD according to an embodiment of the present invention. 1 is a glass substrate, 2 is a thin film transparent electrode, and 2' is a voltage application terminal. 3 is a display electrode on which WO ₃ was deposited. 4 is a light reflecting plate,
5 is a counter electrode, and 6 is a counter electrode voltage application terminal.
7 is a glass case. 8 is an electrolytic solution prepared by dissolving lithium perchlorate in propylene carbonate to a concentration of 1 mol/l. Reference numeral 9 denotes an electrolytic solution injection hole, which is sealed with a thermoplastic resin after the electrolytic solution is injected. 10
is the epoxy resin that bonds 1 and 7 together. 11
1 is a fluororesin film, 12 is air sealed therein, and 11 and 12 constitute the reversible elastic body of the present invention. Electrolyte 8 was injected at room temperature to create an ECD with the above structure. Even when this ECD was left at a high temperature of 80°C, it did not break. Furthermore, even when left in a low temperature atmosphere of -20°C, 11 and 12 expanded in accordance with the contraction of the electrolytic solution, no bubbles were generated, and no movement of the elastic body occurred at all. Change the material of film 11 1
Examples using other gases as No. 2 are shown in Table 1. The ECD structure is the same as in Example 1.

[Table] ○ indicates damage and no bubbles were generated.On the other hand, all ECDs according to the present invention, which had a structure in which the reversible pressure elastic body was not sealed, were filled with electrolyte at room temperature and sealed, and were left in an atmosphere of 60°C. In this way, the reversible pressure elastic body according to the present invention
By sealing it inside the ECD, the pressure can be adjusted well at both high and low temperatures without any inconvenience.The electrolyte can be injected and sealed at room temperature, and from high temperature (80℃) to low temperature (-
We can provide ECDs that can be used in environments up to 20°C. Therefore, the present invention greatly contributes to the realization of a high-performance ECD and its manufacture.

[Brief explanation of drawings]

The figure is a cross-sectional structural diagram of an ECD according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Glass substrate, 3... Display electrode, 5... Counter electrode, 7... Glass case, 8... Electrolyte, 11... Fluorine resin film, 12... Air.

Claims (1)

[Scope of Claims] 1. An electrochromic display device in which a display electrode and a counter electrode are disposed inside a container, the inside of the container is filled with an electrolytic solution, and display is performed using electricity, chemical coloring, and erasing reactions. An electrochromic display device characterized in that an elastic body made of an inert sheet surrounding gas in the electrolytic solution is disposed in the electrolytic solution in the container. 2. The electrochromic display device according to claim 1, wherein at least one of a fluororesin film, a silicone rubber film, a polyethylene film, and a polypropylene film is used as the inert sheet. 3. The electrochromic display device according to claim 1, wherein at least one of air, argon, nitrogen, and helium is used as the gas.