JPS6178890A - Electrochromic material - Google Patents

Abstract

PURPOSE:An electrochromic material which has a short writing time, a wide allowance for an applied voltage, a wide range of selection of solvents, and high density of coloration, and is almost colorless when the color in extinguished, comprising a specified compound. CONSTITUTION:An electrochromic material comprising a compound of formula I (wherein R1-2 each are a (non)substituted alkyl or a (non)substituted aryl) or a compound of formula II (wherein R3-5 each are an alkyl, a (non)substituted benzyl or an aryl; R6-7 each are H, cyano, an alkoxy, a (non)substituted benzyl or an aryl(oxy)). A solution 6 made by dissolving this electrochromic material and a supporting electrolyte (e.g., LiClO4) in an aprotic polar solvent (e.g., dichloromethane) is filled into a display cell which has been formed with a transparent substrate 2 provided with a (semi)transparent display electrode 1 and a backing 4 provided with a counter electrode 3 through the aid of a spacer 5, and is sealed at the side with a seal 7, thus giving a display element.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a novel electrochromic material for an electrochromic display element that performs writing using color development or color change phenomenon caused by voltage application.

BACKGROUND OF THE INVENTION Electrochromic materials are used in electrochromic display devices because they develop or change color upon application of a voltage to form an image.

Conventionally, such electrochromic materials include Fukkayu/Guste/, Iridium Hydroxide/, Iridium Hydroxide,
Inorganic materials such as vanadium pentoxide and titanium oxide, and organic materials such as viologen compounds, ruthenium phthalocyanine, and anthraquinoid compounds are known. However, these materials $ll+ have a long commitment time, 1) The applied voltage required for color development is narrow, 1) When decoloring, 1) Color resistance is low, and it is difficult to select a usable solvent. It has numerous drawbacks, such as being narrow, and there has not yet been a material that satisfies all the requirements for an electrochromic material.

Purpose The purpose of the present invention is to eliminate all of the above-mentioned drawbacks, to provide a short writing time (a wide range of applied voltage), to be almost colorless when erasing, and to have a high degree of color development (a short writing time). It is an object of the present invention to provide new electrochromitter materials with a wide selection.

Structure The electrochromic material of the present invention is represented by the following general formula I or R.

General formula I 11]1 (However, R1y R2 represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and may be the same or different.) General formula ■ (However, R8+ R41R5 represents an alkyl group, a directly substituted or unsubstituted benzyl group, or an aryl group, which may be the same or different. Represents a benzyl group, an aryl group, or an aryloxy group, which may be the same or different.Or R6# RT
may form a moat with the carbon atoms to which they are attached. ] Generally, the electrochromink phenomenon occurs when a voltage is applied.
This is explained by the formation of radical cations and/or cations, or alternatively radical anions and/or anions, in the electrochromic material by oxidation at the anode or reduction at the cathode, resulting in color development or discoloration. Ru. Although it is not yet clear whether the coloring phenomenon caused by the electrochromic material of the present invention occurs at the cathode or the anode, it can be explained in the same way as the general electrochromic phenomenon described above.

Next, typical examples of the electrochromic material of the general formula I will be shown.

Compound A Structure Formula 0 Formula % Compound/L Kizou Formula +1 Compound Point Kizou Formula 0 Also, specific examples of the enctrochromink material of the general formula (■) are as described above.

Compound shop structure formula compound A
Compound A Structural Formula When the electrochromic material of the present invention is used in an electrochromic display element, it is generally dissolved in a suitable solvent together with a supporting electrolyte. Other conventional electrochromic materials can be added to this solution if necessary. Here, a salt soluble in the solvent used is used as the supporting electrolyte. A specific example is LICIO+
eLiBF4 g N'H4ClO41(CHI)+N
Cl+ (CtHs)aNcJ t(C2H4)4NB
r t (CtHa)4NC)J , CCt
Hsun4NCA'04 @ (CxHs)4NBF
+*(C,H,), NClO4, (C,Ho), NBF
4. (C4H,), NJ(SO4,AgClO4゜A
gBF, etc. On the other hand, examples of solvents include aprotic polar solvents such as dichloromethane, chloroform, l,Z-dichloroethane, acetonitrile, flopionitrile, benzonitrile, aceto/propylene carbonate, nitromethane, nitrobenzene, rnv ethyl, tetrahydrofuran. , diochitine, pyridine, dimethylformamide, dimethyl sulfoxide.

Dimethylacetamide, mixtures thereof, etc. are used. Moreover, polar solvents such as water and alcohol can be added to these solvents as necessary.

Next, to explain the display confectionery using the electrochromic liquid as described above, this display element consists of two electrodes, one of which is transparent, as a display cell, and the electrochromic liquid is placed in a sandwich shape inside the display cell. Enclose these 2
Lead wires are taken out from the electrodes and connected to a power source, circuit, etc. to complete the process. The attached figure is a schematic Kf plane view showing an example of this electrochromic display element, in which a transparent substrate 2 having a transparent or translucent display 11 poles 1 and a support 4 having a counter electrode (back electrode 3) are shown. Spacer 5 made of insulating resin such as polyester or polytetrafluoroethylene
After the electrochromic liquid 6 is sealed through the tube, the sides are sealed with a seal 7. The display electrode is made of a transparent electrode material such as indium oxide, tin oxide, or tin oxide, while the counter electrode is made of the same transparent electrode as the above transparent electrode or a metal such as platinum, gold, or aluminum. The substrate or support is made of a material such as glass or plastic.

The present invention will be explained below by way of examples.

Excess IJ 1 The compound of A l -i and LiC10, respectively, are 0
．． N, N so that it becomes 12 mol/l and 0.3 mol/l
- Prepare an electrochromic liquid by dissolving it in dimethylformamide and place it between two pieces of NgSA glass.
Injected through a 3 μm thick polyester spacer,
Created an electrochromic display element. The electrochromic liquid was almost colorless and transparent, although it was slightly yellowish.

Next, when a DC voltage of 3V was applied to both poles of this display element, it colored red, but when the voltage was turned off, it returned to colorless and transparent. In addition, when the voltage was set to 6V, the same results as when applying 3V were obtained, except that the color became slightly darker.
When it was returned to normal, it became colorless and transparent again.

The above results show that the compound of the general formula (1) of the present invention is an electrochromic material that changes color from colorless to red upon application and removal of voltage, and has a wide tolerance range of applied voltage.

Example 2 Compound of field jrXl-2 and AgCl0. my husband ko
, 12 mol/l of cedar and 0.3 mol/l of N, N
- An electrochromic solution was prepared by dissolving it in dimethylformamide, and a device was prepared in the same manner as in Example 1 using this solution. This electrochromic liquid was also almost colorless and transparent.

Next, when a direct voltage was applied to both electrodes of this display system in the same manner as in Example 1, the display system was colored red.

Examples 3 to 8 In place of the compound of A l-1, the above /1il-3, respectively
+1-41-7. An electrochromic liquid was prepared in the same manner as in Example 1 using the compounds 1-41-7. It was almost colorless and transparent.

Moreover, the polish of the obtained display system after voltage application was the same as that of Example 1.

Example 9 Electrochromic M t=
I made it into a device. Although this porcelain had a slight yellow glow, it was almost colorless and transparent.

Same as in Example 1, 3■ on both electrodes of the slightly obtained display element.
When a DC width pressure of 200 mL was applied, it turned blue, but when the pressure was completely removed, it returned to colorless and transparent. In addition, when the voltage was set to 6V, the same results as when applying 3V were obtained, except that one color became slightly darker, and when the voltage was returned to 0, it became colorless and transparent again. It is shown that the compound of the formula] changes from colorless to blue upon application and removal of voltage, and is a Nirecto-u chromic material with a wide tolerance range of applied voltage.

Example 1O An electrochromic liquid was prepared in the same manner as in Example 2, except that the compound A II-2 was used instead of the compound Pil-2, and a device was fabricated. This electrochromic liquid was also almost colorless and transparent.

Next, when a direct current voltage was applied to both poles of the obtained display element in the same manner as in Example 1, the display element was colored blue.

Examples 11 to 16 In place of the compounds of &I-1, the above Al-3+n-4
An electrochromic solution was prepared in the same manner as in Example 1 except that compounds +n-5+n-M-9 and 1l-10 were used, and devices were fabricated. All of these liquids were almost colorless and transparent.

Further, the results of the obtained display element after voltage application were the same as in Example 9.

Effects: The electrochromic material of the present invention has a long writing time and a wide tolerance range of applied voltage necessary for color development. Therefore, rapid switching is possible by applying a high voltage, and when decoloring, it is almost colorless. It satisfies all the conditions as an electrochromic material, such as having a high original color saturation (and being able to use a variety of solvents such as those mentioned above).

[Brief explanation of the drawing]

The figure shows the display λ using an example of the electrochromic material of the present invention.
It is a schematic sectional view showing an example of a child.

Claims (1)

[Claims] 1. General formula I ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R_1 and R_2 are substituted or unsubstituted alkyl groups,
Alternatively, it represents a substituted or unsubstituted aryl group, which may be the same or different. ) or general formula
II▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R_3, R_4, and R_5 represent an alkyl group, a substituted or unsubstituted benzyl group, or an aryl group, and may be the same or different. R_6, R_7 represents hydrogen, halogen, cyano group, alkoxy group, substituted or unsubstituted benzyl group, aryl group, or aryloxy group, and may be the same or different. Alternatively, R_6 and R_7 are the carbon atoms to which they are bonded. (May form a ring with atoms.) An electrochromic material represented by