JPS6073526A - Electrochromic display element - Google Patents

Abstract

PURPOSE:To enable a display element to develop versatile background colors by using the oxidation color or reduction color of an EC material as the background color of an all solid-state ECD. CONSTITUTION:The oxidized or reduced EC material is used as the background colors of the transparent pattern for display of an all solid-state ECD. As an embodiment, transparent display electrodes 2 and an EC material layer 3 are formed on a glass base 1, then, a solid-state electrolyte layer 4 contg. an oxidizing or reducing agent is formed on the layer 3, and finally an opposite electrode 5 is arranged on the layer 4. All the region of the EC material layer can be colored to the oxidation or reduction color. It is used as the background color, and only the parts of the EC material layer 3 in contact with the electrodes 2 are changed in color by the electrochemical reaction to execute color display. As a result, a background color sharp in contrast to the displayed transparent pattern is obtained without impairing display memory.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electrochromic display device (hereinafter abbreviated as ECD), and more particularly to an all-solid-state ECD.

[Conventional technical background and its problems]

So-called all-solid-state ECDs, which are mainly composed of a thin-film solid electrochromic material and a solid electrolyte, have the display memorability common to ECDs, but also have no risk of liquid leakage and can be made thinner. Because of its advantages such as the fact that it is

Solid electrochromic materials include Wo 3 and M.
In addition to transition metal oxides such as oO3 and IrOs, organic compounds such as rare earth metal shifters, cyanine, and viologen compounds are known.

On the other hand, as a solid electrolyte that can be used in combination with the solid electrochromic material described above to form an all-solid-state ECD, β-A1203. RbAg4I5+Na5Zr2
-Inorganic compounds such as Si2POtz, LiaN, and NazYSi401z are known, but in recent years, polymer electrolytes such as polystyrene sulfonic acid resin and par-length lolosulfonic acid resin, polymer compounds such as polymethyl methacrylate, and electrolytes such as LiCIO4 have been developed. A composite solid electrolyte has attracted attention because it is easy to form a thin electrolyte film, and is widely used as an electrolyte layer in all-solid ECDs.

Conventionally, a reflective all-solid-state ECD using the electrochromic material and solid electrolyte described above has an electrochromic material layer (3) on a transparent polarization (2) on a glass substrate (1), as shown in Figure 1. A solid electrolyte layer (4) in which fine pigment particles are dispersed is provided in close contact with the thin film of the electrochromic material layer (3), and a counter electrode is provided on the solid electrolyte layer (4). (5).

Such conventional reflective all-solid-state ECDs use a glass substrate + 1) for the purpose of making the display pattern and its background clear.
An electrochromic material layer (3) is provided only on the display pattern transparent electrode (2) provided above, and the color around the display pattern transparent electrode (2), that is, the background color, is the solid electrolyte layer (4). In order to make this background color vivid, pigment fine particles had to be dispersed and mixed into the solid electrolyte layer (4).

In addition, the electrochromic material layer (4) is colored in a normal state without using the solid electrolyte layer (4) as a background color.
As shown in Figure 2, the reflective all-solid-state KDD using 3) has a thin film of an electrochromic material layer (3) on the glass substrate (1) and the transparent electrode (2) on the glass substrate (1). , furthermore, a solid electrolyte layer (4) and a pair of shield electrodes (5) are provided on this, and the color of the electrochromic material layer (3), that is, in a state without oxidation or reduction, is Color was used as the background color, and display was performed using oxidation or reduction colors. However, since there are very few types suitable as electrochromic materials, the contrast between the display color of the display pattern and its background color is unclear, and the combinations thereof are also very limited.

[Purpose of the invention]

An object of the present invention is to provide a display element that uses the oxidation color or reduction color of an electrochromic material as the background color of an all-solid-state ECD.

[Summary of the invention]

The present invention is an all-solid-state electrochromic display element characterized in that an oxidized or reduced electrochromic material is used as the background color of a transparent pattern for display, and specifically, By oxidizing or reducing an electrochromic material layer provided in a thin film form over almost the entire area of a transparent glass substrate on which a transparent electrode has been previously provided by a chemical reaction, the entire area of the electrochromic material layer becomes an oxidized color or a reduced color. The color band is used as the background color, and only the portion of the electrochromic material layer that is in close contact with the transparent 4 electrodes for display causes a color change for display by an electrochemical reaction.

An electrochromic material layer is formed on a glass substrate provided with a transparent electrode for display by a commonly used means such as vacuum deposition, and then a solid electrolyte forming paint containing an oxidizing agent or reducing agent is applied on the electrochromic material thin film. This is carried out by coating and drying the solid electrolyte layer to form a solid electrolyte layer, and then providing a counter electrode on top of the solid electrolyte layer.

Another aspect of the present invention is to immerse an electrochromic material layer provided over almost the entire area of a transparent glass substrate provided with a transparent electrode for display into a liquid containing an oxidizing agent or a reducing agent. After oxidizing or reducing the electrochromic phase layer by leaving it in an oxidizing gas or a reducing gas, a normal solid electrolyte forming paint containing no oxidizing agent or reducing agent is applied to the surface of the electrochromic material layer.・This can also be done by drying.

This is the solid electrolyte type used in the practice of the present invention.

Examples of commercially available paints include polyvinyl alcohol.

Polyethylene glycol, polyvinyl pyrolide.

Methyl vinyl ether and maleic anhydride copolymer.

Casein, gelatin, glue, egg white aluminum/.

A paint in which a hygroscopic polymer substance such as gum arabic or a cellulose derivative and a deliquescent substance are dissolved is suitable for the purpose of obtaining a good solid electrolyte that allows the reversible electrochemical reaction of electrochromic materials to continue. Even if a substance that oxidizes or reduces the electrochromic material is added to this paint, no problem will occur if the substance does not cause decomposition of the deliquescent electrolyte.゛Furthermore, fine pigment particles such as Ti02 are dispersed in the above-mentioned paint from the transparent side for display so that the shadow of polarization, which is provided in close contact with the solid electrolyte layer as a counter electrode of the transparent electrode for display, cannot be seen. Good too.

In addition, ZnCl2. A
A'C/3,5bC73,YCl3. InCl2. In
C1a, GdCl3°GaCl2. GaCl3. CaC
J'+, CrCl2. CrCl3,5rC12,CsC
CCeCl3. BiCl3. BeCl2, LaCl3
．． BeF2. T#'3 +5nF4+KFtuF6,
SbF+ IN) I4F, NH4Br, ZnBr
2, YBr 3 , CdBr 2 , GaBr 3+
CaBr2. SnBr4+CeBr3+BeBr2. M
gBr2. LiBr, AlI3゜Ca I 2 + S
r I 2 * Na I ghog I 2 HL
I I +KI 3 e P 5C1l 31 KN
Oz I NaN02 +Al(NOa) 3+Yb
(NO3) 3, Y(NO3) 3. In(NO3
) 3. Ga(NO3)'a +Ca(NO3) 2
, LiNO3, IVIg(NO3) 2 , (NH
30H)NO3, La(NOa) 21Zn(NOa
) 4 , Hg(NO3) 2 , 5e(NO3)
2, Ce(NO3) 3, Tl(k'o3) 31
Th(NO3) 4 , Zn(CA'03) 2 ,
LiClO3, Ca (CAO3) 2, In(C
lOa), iPb (C103) 2 , AgCl0.
1, NaH8O4, Mg (ClO4) 2, Ca
(ClO)2.

HzSe03+KzSe03. NH45O3NH2,H
zPHO3, 2PH03.

(NH,i)PHOa, Na2PO4, Na2P
H03, Ni202, P2O5, P2O4.

As2O5+Na2O, P20a+KzS, Na25e
, C52S, Na2S, Rb25°HN (zOz 1
KPH202, NaPH202, NH4CN, KCN
, Au('CN) 3 , C5CNNaCN, KOH
,5r(OH) ,CsOH,NaOH,Rb(OH)
, C82CO3゜Na 2C03, Li 2CO3,
Zn(5CN) 2 , NH4SCN, KSCN, Ca
(5CN) 21NaSCN, Ba(SCN)2+KS
eCN, (NH4)zZn(804)2.5b2(SO
4) 2Yb(SO4)+Ga2(SO4)3. HgSO
41KHso4. NaH8O4,5n(SO4)2B
i2(804)3r(NH6)2804,
(PI(4) 2804, H3PO4, ni2■廿04
゜Na2HPO4, KH2PO4, Ca (H2PO4)
2, (NH, a) 2s203°K2T to 282031
e04. 3AsO4, KA802. 2Si03. N
FI4BO2, KBO2゜K2MOO4, (NH4)Z
nCla, (NH4)NoC1l3, N0BF
4, NaNH2.

N1 (zOH, Na 2S 2071 to 4P 207
, I(SI(, Na5H, K3ASS 4 , N2H
@CA' 2I (PO3) x * Yb C1l 3
+ u CIJ 4 + u CZ 5 T SmCA
3 + Fe C1l 3 + Cu C1l 2
r(NH4)NiC1j 3. VC1j2. VOCl
2. N1(C104)21KNH2,MoOCl4+H
02Br2. N1(N03)z, FeI2. Ti2(S
O4)a, Mn2(SO4)3゜ErCl3. AuCl
3. uC13, PbCl2. MnCl2. RhCl3.
CoBr2゜FeBr 3 , MnBr 2 , MnI
2, PI 3 , Ge I 4 , Nf(4Co
CJi! 3, Na1V1n04 +MnO3, Cr
0a, Rb55. C0(NO3)2. Fe(SCN)3
．． 2C83゜ZnCr2O7, Na2Cr2O7+N
a5(Fe(CN)a)+uozI2. Au2(SO4
), 3PdSO4,08CA2. IrBr4. Cu(N
O3)2. TiCl3. Fe(NOa) 3゜InCl
, NbCl5. NiCl2. ICl3,5eC14,A
lBr3. InBr3°SmBr3. TlBr3. Ti
Br4. NiBr2. B1Br3. H2PtCA6. H
AuCl, iK2HgI4. AgF, InI3. H02
(NO3)2. (NH4)zce(NO3)6+Pb(
NO3)25Be(NO3)2. Cs02. Li2S,
2(Pt(CN)4), Fe2(SO
4) At least one day's sleep or more selected from a+ etc., and these deliquescent substances and strong electrolytes such as KF,
KCl, KBr, KI, NaF, Na(J!,
NaBr, NaI.

LiCIC)a etc. may be used in combination.

Furthermore, when a substance capable of oxidizing or reducing an electrochromic material among the above-mentioned deliquescent substances is dissolved in a paint for forming a solid electrolyte, it may not be necessary to add a substance that oxidizes or reduces an electrochromic material. According to the present invention, by using an oxidized or reduced electrochromic material layer as a background color without using a solid electrolyte layer containing dispersed pigments, the contrast with the display color of the display transparent pattern is clear. You can get a different background color.

[Embodiments of the invention]

Example 1 As shown in FIG. 2, a transparent conductive film made of indium oxide provided on a transparent glass substrate (1) was etched to form a transparent electrode for display (2).
A-balen was deposited as an electrochromic material layer (3) on the surface of the glass substrate (1) on which the display transparent electrode (2) was formed using a vacuum deposition apparatus.

This electrochromic material layer (3) of tetrathiafulvalene was yellow in color and had a thickness of about 100 OA.

Next, 0.001 no of Na25zOs was used as an oxidizing agent.
When immersed in an aqueous solution, the Tetrathia 7A/Valene electrochromic layer (3) turned purple.

1. Dissolve 5 g of polyvinyl alcohol with a degree of polymerization of 2400 and 5 g of polyethylene glycol with a degree of polymerization of 400 in 100 g of pure water, and disperse and dissolve 30 g of TiO2 fine particles as a white pigment and 216 g of CaCl as a deliquescent electrolyte to form a solid electrolyte. I obtained the paint for use. Furthermore, TiO
Since air bubbles are included in the paint due to stirring when dispersing and dissolving CaCl2 and CaCl2, approximately 30 g of methyl alcohol was added as an antifoaming agent. This removed air bubbles contained in the paint.

After applying the thus obtained solid electrolyte forming paint onto the reddish tetrathiafulvalene thin film,
After drying in a high-temperature bath at °C to form a solid electrolyte M(4) with a thickness of approximately 0.1 mm, Au
A counter electrode (5) was provided by vacuum evaporating.

This pair of electrodes (5) was used as an anode, and -1,OVo
When lt was applied, the transparent d-pole (2) became visible within 0.5 seconds.
Only the electrochromic material layer (3) of tetrathiafulvalene in contact with the color changed to its original green color. That is, through the above steps, a reflective all-solid ECD with a purple background color and a yellow color was easily obtained.

+1. It was confirmed that the color did not return to purple unless OVol was applied.

Further, according to the present invention, as in the electrochromism phenomenon of rare earth metal ditalocyanine, the coloring of an electrochromic material changes continuously from violet to blue-green-yellow-red depending on the voltage between the counter electrode (5) constituting the ECD and its polarity. A desired background color of the chromic material layer (3) can be arbitrarily selected from among the above-mentioned colors.

Furthermore, according to the practice of the present invention, the oxidation or reduction reaction of the electrochromic material by the oxidizing agent or reducing agent contained in the solidified electrolyte will not normally occur. Unlike liquid ECDs which provide an oxidized color display in the reduction envelope of the electrochromic material layer (3) designated by the number ZAO7, the memorability of the display is also not impaired.

Example 2 Polyvinyl alcohol 5gi with a polymerization degree of 2400 and a polymerization degree of 4
00 polyethylene glycol 5 g 'e 100
30 g of TiQ2 fine particles and 216 g of CaC# were respectively added to this solution and stirred using a sieve to disperse and dissolve. Bubbles generated during stirring were defoamed by adding about 30 g of methyl alcohol. Furthermore, about 0.1 g of N'azSzOs was added,
A coating material for forming a solid electrolyte according to the present invention was obtained.

A glass substrate (1) having a thin film of an electrochromic material layer (3) made of yellow tetrathiafulvalene on a Renmei' electrode (2) was immersed in a paint containing 1 cm per minute. The mixture was drawn up at a high speed to form a paint film on the electrochromic material layer (3) of tetrathiafulvalene. By applying this paint, yellow tetrathiafulvalene changed color to purple tetrathiafulvalene.

Further, in the same manner as in the example, after drying the coating film, gold was vacuum-deposited on the surface of the solid electrolyte membrane using a transparent counter electrode (return (2)), and the electrode 5) was used as an anode. Transparent 4 poles for display (2
), only the tetrathiafulvalene electrochromic material layer (3) in contact with the transparent electrode (2) changed color from purple to yellow, resulting in a bright display pattern.

Example 3 After etching a transparent conductive film made of indium chloride provided on a transparent glass substrate (1) to form a transparent quasi-electrode (2) for display, tetrathiafulvalene was electrochromically etched. As the material layer (3), a glass substrate (IJ
A transparent electrode (2) was vacuum-deposited on the display surface. This tetrathiafulvalene vapor-deposited film had a yellow color and a thickness of about 1000×.

The tetrathiafulvalene thin film thus obtained was coated with the glass substrate (1) at 0.00%. When immersed in the I N + H2O2 aqueous solution, the tetrathiafulvalene electrochromic material layer (3) turned purple.

Meanwhile, the solid electrolyte forming paint used in Example 1 was applied to the thin film surface of the purple electrochromic material layer (3),
A reflective all-solid ECD was obtained in the same manner as in Example 1. The obtained ECD could be used practically as a clear display screen with a purple background color and a yellow display color.

Example 4 A reflective gold solid ECD was used in the same manner as in Example 2 except that a complex of lutetium and phthalocyanine was used as the electrochromic material layer (3).

The background color of the obtained ECD is red and the gold counter electrode (5)
On the other hand, the transparent electrode (2) for display has -1,0 VoAt
When 1.5 VoAt is applied to the transparent electrode (2) for display, a blue display color appears when applied to the counter electrode (5), the electrochromic material layer (3) on the transparent electrode for display (2) clustered in red.

The compound of lutetium and phthalocyanine is green and has a reflective all-solid state I! obtained in this example. The color of the CD can also be changed from yellow to green to blue by changing the voltage applied to the transparent quadrupole (2).

[Brief explanation of the drawing]

The drawings show a conventional example of an electrochromic display element and an example of the present invention. Figure 1 is an enlarged sectional view of a conventional electrochromic display element using a solid electrolyte layer as a background color, and Figure 2 is an enlarged cross-sectional view of an electrochromic display element using a solid electrolyte layer as a background color. FIG. 3 is an enlarged cross-sectional view of an electrochromic display element of a conventional example and an example of the present invention in which a material layer is used as a background color. 2: transparent polarization, 3: electrochromic material layer, 4: solid electrolyte layer, 5: counter electrode. (7317) Agent Patent Attorney Noriyuki Chika (and 1 others)
Figure 1 Figure 2

Claims (1)

[Claims] In electrolytically corroded solid state electrochromic display elements,
A reflective all-solid-state electrochromic display element characterized in that an oxidized or reduced electrochromic material is used as the background color of a transparent pattern for display.