JPS59195629A - Electrochromic display body - Google Patents

Abstract

PURPOSE:To obtain a matrix display type electrochromic display body (ECD) causing no cross-effect phenomenon by forming one of transparent and counter electrodes on the display side as a divided electrode, diving a solid or semisolid proton donor layer into parts, and filling the gaps with an insulating layer. CONSTITUTION:Tungsten oxide is vacuum-deposited on a display section by an electron beam heating system to form an EC layer 4. Antimonic acid as a solid electrolyte is kneaded with glycerol and water in 5:1.2:0.5 weight ratio to prepare ink, and a PS layer 5 is formed by screen printing with the ink and drying. The layer 5 is coated with a mixture of 10 parts electrically conductive carbon-base paste with 3 parts Prussian blue as a reversibly oxidizable substance by screen printing to form a reversibly oxidizable counter electrode 6. After forming a collector layer 7 with electrically conductive Ag-base paste, the layer 7 is coated with a photosetting resin adjusted to V4-V5 viscosity with a Gardner-Holdt viscometer by screen printing, and the resin is immediately photoset by exposure to an ultraviolet metallic halide lamp of 3kW set apart from the resin by 20cm distance for about 10sec to form an intermediate insulating layer 8. Leads 10 are then formed by screen printing with electrically conductive Ag-base paste.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the improvement of electrochromic display devices (electrochemical color display devices, hereinafter abbreviated as ECD), and relates to the improvement of electrochromic display devices (electrochemical color display devices, hereinafter abbreviated as ECD). This invention relates to an ECD that is easy to manufacture and has improved display effects.

ECDs can be roughly divided into those whose basic element, electrochemical coloring substance (hereinafter abbreviated as EC layer), is an inorganic substance and those whose EC layer is an inorganic vII substance. Another basic element, the proton (or cation) donor layer (hereinafter abbreviated as ps layer), can be distinguished into solid and liquid types. When the EC layer is made of a liquid organic substance such as biologen, or the PS layer is a liquid, it is necessary to have a sealed structure to prevent liquid leakage and outside air from getting in, which makes the structure of the display complex. Moreover, due to the complexity of the manufacturing process, the cost was high, and other display materials such as LEDs and liquid crystals could not be used immediately.

Such drawbacks are exacerbated as the number of pixels displayed increases, such as in matrix display.

The present inventors applied for a patent application in 1973 for the technology that solved these problems.
No. 6-26358 (% Publication No. 57-139721)
and Japanese Patent Application No. 56-87760 (Japanese Patent Application No. 57-20252)
It has already been shown that the configuration of the ECD was simplified by making the PS layer a solid layer that could be formed by printing, as disclosed in Japanese Patent Publication No. 3 (Japanese Patent No. 3).

According to the prior art by the present inventors, gc
The ability to produce PV has made it extremely easy to create a matrix display for ECD, but conventionally, matrix displays for ECDs, like matrix displays for liquid crystals, had the effect that when one matrix pixel was colored, it affected the surrounding pixels. The surrounding 1M elements also produced some coloring, which had the disadvantage of deteriorating the appearance and contrast of the 1M product. This development is also called crosstalk or cross effect phenomenon.

This caused a big problem with the ECD drive.

In addition, ECDσ) where the EC layer or PS layer is a liquid
Since it is necessary to separate each pixel and make it into cells for II Knox and multicolor, it is extremely difficult to convert to II pixels, and a significant increase in manufacturing costs is unavoidable.

In addition, ECD (or even printed ECD)
As described above, since it is necessary to divide each pixel into cells, it is relatively complicated and difficult to extract one node from the counter electrode on the back surface. For example, even if a thin copper wire coated with vinyl chloride resin is contacted with a low melting point powder or silver paste, the work efficiency is extremely low. A method of making contact χ from the back surface with a small spring or the like is also considered, but this method also has some problems because the BCD must be completely sealed to avoid changes over time due to moisture and oxygen.

The present inventors provide a new technique to improve these drawbacks.

In addition, the inventors of the present invention filed the above-mentioned patent application No. 56-87760.
By applying new printing technology according to the No. 1 issue and further modifying the structure of the electrodes, electrodes, and insulating layers, we propose a matrix display ECD that does not cause the aforementioned cross-effect development. The present invention was developed in an effort to provide an ECD that can easily perform multicolor display and is easy to manufacture.

That is, 1. The electrochromic display of the present invention basically uses a transparent substrate such as glass or plastic as a support, and 1. has at least an electrochemical coloring layer (EC layer) between the transparent bar on the display side and the counter electrode. and a solid proton donor layer (
PS layer) is interposed to form a neutral electrochromic display body, in which at least one of the transparent electrode on the display side and the counter electrode is separated from each other, and is a solid or semi-solid proton donor 1? ! ire is similarly separated from each other, and an insulating layer in a negative pattern is provided to fill the gap between them.A counter electrode is provided on the proton donor layer, and a lead extraction portion of the counter electrode is provided. The present invention is characterized in that an intermediate insulating layer is provided, and a conductive layer is provided which is converged from the plurality of lead outlet ports to an end portion on the transparent substrate to serve as a lead portion, and in addition, a protective layer is laminated. It is an electrochromic display.

In the following, the ink for the solid proton donor layer and insulating layer formed by the printing method will be described. First, the preferred main components of the solid PS layer are:

Titanic acid, stannic acid (SnO□・xH20), antimonic acid (S b203 ・XH20 or 5b2o, ・X
H20), zirconium R(Zr(Of()a Hx[
(20), niobic acid (Nb20., -XF (20)
, tantalic acid (Ta203.xH20), and silicic acid, or a mixture of two or more thereof. These materials are sometimes called hydrated metal oxides or hydrated metal oxides, but they are simply titanium oxide and tin oxide.

antimony oxide, zirconium oxide, tantalum oxide,
Care must be taken as this is completely different from an oxide such as niobium fI mixed with water from the outside.

Since these above-mentioned materials exhibit white color in a powder state, they are effective in increasing the whiteness of the base of a display device, and moreover, they themselves exhibit high proton conductivity. Their resistance value is as low as 1X10' to 1X10'Ω/α at room temperature, and the addition of these additives does not result in poor color response of electrochromic display devices; on the contrary, both response speed and color density are improved. It is something that

In addition, powders of titanic acid, stannic acid, zirconic acid, antimonic acid, niobic acid, tantalic acid, titanic acid, etc. mentioned above have the characteristics that they can be used with the addition of small amounts of binders used in printing inks and coating compositions. , their proton conductivity is preserved, and these layers, printed or painted and cured, are useful as solid 28 layers of an electrochromic display.

As a binder, the vapor pressure at 20C is 0, lm.
Polyhydric alcohols, water-soluble polymers, or aqueous emulsion-type polymers that are normally liquid at mHg or less.

This is preferable for maintaining proton conductivity. Further, as a solvent for forming an ink or coating composition, water or a water-soluble solvent such as lower alcohol, lower ketone, lower ether, etc. may be used. Further, a polymer having a sulfonic acid group may be used as a binder or a proton donor, and one example of this type is acrylamide methylpropanesulfonic acid. Examples of the polyhydric alcohol include polyethylene glycol and glycerin, and when these are used, the PS layer can be formed as a relatively soft layer with solid or semisolid properties. These materials have the advantage that they can be formed by, for example, screen printing or various coating methods, and can be applied to a wide range of thicknesses. For example, a thickness of 2 to 2000 μm can be used, and a thickness of 50 to 4 [10 μm is particularly preferred.

On the other hand, it is basically preferable to use transparent insulating resin as the insulating layer. 1. Transparent here means that unnecessary companion phases are not given to the display surface of the ECD, but as will be described later, a coloring agent is added to the insulating layer and the PS layer to make the ECD It is also a layer that can give a convenient hue to the image. Curing resin that does not contain solvents,
For example, an oxidation polymerization type resin, an ultraviolet curing type resin, a crosslinking polymerization type resin, etc. can be used as a basic component of the insulating layer.

These resins are printed in a checkered pattern when they are in an uncured state,
After that, it can be cured to form an insulating layer. A cured epoxy resin layer is one example that can be used as a durable layer.

Regarding the EC layer, it is good if it has electrochromic properties and is solid or almost solid.
It is an organic or inorganic substance. For example, a film-like EC layer containing a viologen derivative in glycerin or polyvinyl alcohol, a mixed layer of these polymeric electrochromic materials and a conductive filler, or a layer containing tungsten oxide (WO3), molybdenum oxide ( MoO3).

Titanium oxide (TiO2), vanadium oxide (v2oa)
etc. were vacuum evaporated onto the display electrode using an electron beam heating system.
Freeze++'A is an example.

Next, regarding the counter electrode, it is possible to attach a metal plate such as copper or aluminum to the solid PS layer while maintaining electrical contact, or to apply conductive ink such as silver paste to the solid PS layer.
Apply on top of 3 layers.

A thin metal film is formed by vacuum evaporation, CVD, ion blating, etc., and can be used as a counter electrode, but a part of the counter electrode contains a reversible oxidizing substance. Depending on the time required for 1 estrous color, 1
It can be shortened to 73 to 1/4. In particular, it is noteworthy that a counter electrode containing such a reversible oxidizing substance can also be formed by a printing method, and that an ink composition for this purpose can be provided.

Added to the counter electrode (2) Effective reversible oxidizing substances include titanium dioxide, nickel oxide, cobalt oxide, iron oxide (p.
eo, Fe2Cl5 or Fe304), silicon dioxide, lead oxide, steel oxide (C:uO), iron sulfide (, Fe
In addition to metal oxides and sulfides such as s or Fe52), bismuth oxide (Bi2o3), and niobium sulfide, hydroquinone derivatives and iron berlinate derivatives can be mentioned.

Reversible acid (1i) In addition to the above-mentioned reversible oxidizing substance, carbon powder is preferably coexisting in the material layer as a conductive filler to increase conductivity. Specifically, Ketjenblack is used.

Examples include acetylene black, carbon black such as conductive furnace black, and carbon fiber. These conductive fillers and powdered reversible oxidizing substances are combined with a suitable resin binder to form a reversible oxidizing substance layer, and the resin binder is an acrylic resin.

Vinyl chloride resin, epoxy resin, melamine resin.

Guanamine resin, alkyd resin, methacrylic resin, etc.
Resin binders used in common printing inks can be used. By kneading these resin binder, conductive filler, and reversible oxidizing substance with a volatile solvent, an ink or coating composition for forming a reversible oxidizing substance layer is created. Does the volatile solvent mentioned here mean that it is applied using a printing method such as screen printing? If you think about it, the solvent evaporates during printing, so the ink composition is less likely to change, and it is preferable that the ink dries quickly after printing.
<It has a boiling point of 150C to 270C and is a true solvent for the resin binder. Examples include diethylene glycol monoethyl ether acetate, diethylene glycol motsubutyl ether acetate, tripropylene glycol monomethyl ether, diethylene glycol monobutyl ether, 2-phenoxyethanol, N-methylpyrrolidone, 2-pyrrolidone, and the like. These solvents are completely removed from the reversible oxidizing substance layer after coating and drying, except for a negligible trace amount remaining.

Furthermore, the above-mentioned ink for forming reversible oxidizing substances.

It is also possible to add a small amount of surfactant to improve printability.

As a counter electrode, it is in contact with this reversible oxidation material layer.

A Kl conductive layer may also be added. Either use a commercially available silver paste, or apply a cross-conductor ink containing a metal conductive filler selected from silver, palladium, nickel, copper, etc., a resin binder, and a volatile solvent.
It is dried and laminated as a highly conductive layer, which improves color development responsiveness.

This is because the reversible oxide layer alone has poor conductivity, but by adding this good conductivity layer to the back side, the conductivity increases and the voltage drop decreases (resulting in improved color development/decolorization response). Conceivable.

In addition, the transparent electrode on the 1st display side and the 1st one are tin oxide (sno
2) Indium oxide (In2O3)' Y- or a conductive material formed by forming a thin film of gold of 400 A or less by a thin film forming technique such as vacuum evaporation or CVD can be used.

According to the ECDK of the present invention, coloring of one display can be easily achieved by adding a coloring material to one or both of the solid PS layer and the insulating layer. As mentioned earlier, the solid PS layer and insulating layer are formed by printing methods such as screen printing.

A can containing about 0.01 to 10% by weight of coloring material in the ink? EC of any hue can be created by adding
It can be given to D. The e-coloring agent is preferably a coloring agent that can exist easily without being dissolved or chemically changed in the solvent or binder used in the ink. It has been confirmed that such colorants have no effect on conductivity (and no adverse effects are observed even after repeated coloring and fading lifespan (KN).When a solid PS layer is colored,
'When the E-0 layer is in a decolored state, the EC layer becomes transparent, and the colored background PS layer becomes visible on the display surface.

When the EC layer is in a colored state, only the color of the EC layer is viewed, or a mixed color of the EC layer and the ps layer is developed on the display surface. The insulating layer has a lattice pattern, and between the matrix pixels that change color and disappear, [[means that any color is given.

Additionally, it is significant that the 28 layers in the grid pattern and the insulating layer in the negative pattern (for example, lattice pattern) are formed by printing means.

The printing method is essentially a means of mass-replicating patterned films, and it can be said that the printing method's main feature is forming PS layers and insulating layers with complex shapes.

In the present invention, the selection of electrode patterns can be changed depending on the purpose. In a fine matrix pattern in which one pixel of the matrix is less than about one fighting angle, the transparent electrode, which is the electrode on the display side, is slammed by a known method using a photosensitive resist, and the counter electrode can be a single flat electrode. .

In the case of a relatively coarse matrix pattern in which the pixel size is approximately 11 diagonals or more, it is convenient to use a single transparent electrode as the transparent electrode on the display side, and form the counter electrode as each separate pixel in the matrix pattern. be.

The reason for this is that fine patterns of less than 1 angle can be etched using a thin film of 11 g using mask vapor deposition, photo etching, and lift-off methods.
This is because it is advantageous to use the patterning technique described above, and the transparent electrode according to the display rule is a thin eyelid suitable for such patterning technique.

In the ECDK of the present invention, at least one of the electrodes is formed into a matrix, and furthermore, according to the shape of this electrode, a solid p
The s-layer is made into a matrix, and moreover.

Since an insulating layer is provided in a grid pattern in the gaps created between each separated PS layer by forming a matrix, a voltage for display is applied between the transparent electrode on the display side and the counter electrode. When this happens, charge carriers such as protons (H) or cations that are involved in coloring and fading of the EC layer conduct only within the solid PS layer which is individually isolated and insulated.

Charge carriers do not diffuse into surrounding PS layers adjacent to one PS layer and become conductive.

In other words, the charge carriers involved in color development/decolorization are supplied only to the part of the EC layer that is in gaseous contact with the matrix-like solid PS layer. There is no possibility that discoloration occurs in a portion and spread discoloration occurs in the surrounding EC layer. That is, an ECD with a matrix display that does not cause cross-effect phenomena is provided.

Furthermore, the 0ECD of the present invention is an ECD that can form a large number of color developing/deleting pixels on a single support.

Its structure is solid as it is entirely solid. In addition, the solid PS layer and insulating layer are formed by printing means such as screen printing.

Patterning such as a matrix or a grid pattern can be easily performed, which provides great convenience in manufacturing the ECD of the present invention, and the ECD has a low manufacturing cost. Since it has a structure in which a large number of matrix pixels can be incorporated into a small display, the pattern that can be displayed is rich in variety, and it is an IJ display type electrochromic display that has entered the practical range.

In addition, in the OECD of the present invention, contact is made from the opposing electrode of each separated cell through an intermediate insulating layer that is laminated except for the lead extraction portion of the opposing electrode. A lead is taken and the conductive layer of this lead is formed using a printing method so as to collect it at the edge of the substrate. Therefore, conduction can be obtained very easily, and manufacturing thereof is also very easy and inexpensive. Furthermore, since it uses a printing method, there is the advantage that the size and shape of the cells can be changed freely. The shapes of cells and dots may be concrete patterns, designed characters, or the like. Another advantage of being able to form lead patterns by printing is that the resistance value up to the counter electrode can be significantly lowered, so even if the area is large, ECD
In some cases, the color development/decolorization response can be set almost uniformly and quickly. For example, the sheet resistance of a printed lead pattern is 0.1Ω/
It can also be less than ohm/square centimeter.

In the present invention, since the intermediate insulating layer is provided in this way, the conductive layer of the lead portion can be freely cut and the resistance value of the lead can be set arbitrarily. As described above, the resistance value of the lead can be adjusted to a desired value by adjusting the edge width, thickness, or printing ink material. As described above, the EC of the present invention
D has various advantages.

An embodiment of the 0ECD of the present invention will be described below based on one drawing. That is, FIG. 1 is a schematic sectional view of the 0ECD of the present invention, and FIG. 2 is a schematic plan view of the ECD of the present invention viewed from the back side.

[Example 1] Transparent electrodes (21) made of indium oxide are provided in a pattern on a glass substrate (1), and the non-displayed areas on the transparent electrodes (21) manufactured by Toyo Ink Manufacturing ■Product name 5S-250 are printed using a screen printing method.
Toyo Ink Manufacturing, which added pigment to 00 Ink Medium■
Screen printing ink product name 5S25-611
(white), SS2.5-+262 (yellow), 5S25
-qll(@) was mixed and toned and printed by a screen printing method to form an insulating layer (3).

Next, tungsten oxide was deposited on the display area to a thickness of about 4500× by vacuum deposition using an electron beam heating method to form an EC layer (4).

Next, as a solid electrolyte layer, antimonic acid and glycerin were kneaded into an ink with a water weight ratio of 5:1.2:0.5, and a film thickness of about 300 μm was formed by screen printing.
After drying to form the PS layer (5), a carbon-based conductive paste Algyoku Kasei (stock trade name Dotite was printed and laminated using a screen printing method to form a reversibly oxidizable counter electrode (6), and further A
I-based conductive paste manufactured by Fujimo Shokusei Product name Dotite XA
-167 is laminated to form a current collector layer, and then as an intermediate insulating layer (8), the viscosity is measured using a Gardner bubble viscometer.
Screen printing of photocurable resin adjusted to 4 to V5 1-
Immediately after laminating the layers, they were exposed to light for about 10 seconds from a distance of 20 degrees using a 3 kW ultraviolet metal halide lamp to form a film.

The pattern of the intermediate protective layer (8) is printed and laminated on almost the entire surface, leaving a window-like part as a lead extraction part (111) so that the lead can be removed.The photocurable resin is manufactured by Inu Osaka Organic Chemical Industry Co., Ltd. under the trade name Visco. -) UV-1801 was used.

After this, a lead (101) was screen printed using A% conductive paste (A% conductive paste) This corresponds to a colored dot pattern, and in FIG. 1, this is a portion where an EC layer (4), a PS layer (51), a counter electrode (6), etc. are sequentially laminated.

In this way, since the conductive counter electrode (6) is laminated on the circular pattern (7), if the lead +I01'a' is used, the lead will be removed unless the intermediate insulating layer (8) is provided. (10) causes contact with other dot patterns, resulting in short circuits and malfunctions. Lead (10
) After printing, UV resin was further laminated to a thickness of 300 μm as a protective layer (9) over the entire surface, leaving only the lead ends (I21).

The transparent electrode of the ECD formed as described above (21 is the negative electrode and the lead end (121 is the positive electrode) has a voltage of 1.6V.
When this voltage was applied, the EC layer (4) developed a blue color.

When the positive and negative signs were reversed, the color disappeared immediately. Color development and fading for 1 second to 1 second was possible over 106 times.

In the above embodiment, a circular dot matrix of 6×3 in the vertical and horizontal directions was used as an example, but even if it is not %[3×6, p
It doesn't have to be a circle. For example, a 5 x 7 matrix is preferred for alphavent character display, or a 40
Large display of about 0x200, POP including video
Displays and the like are also included in the present invention. In addition, although the material of the intermediate insulating layer is a photocurable resin as an example, it is a low-temperature thermosetting resin.

The curing method is not particularly limited, such as oxidative polymerization type. The photocurable resin may have any curing mechanism such as a radical polymerization type, a radical addition type, a cationic polymerization type, or an acid curing type. As prepolymers, unsaturated polyester resins and their urethane-modified, unsaturated alkyd resins.

Acrylic resins, epoxy-modified resins, urethane-modified resins, polyester-modified resins, etc.5 This invention is not limited to these. Furthermore, if the protective layer is to prevent the permeation of moisture and oxygen from the outside air or atmosphere, the thickness of the resin film of the protective layer can be made thicker, or a two-component curing type epoxy resin can be added.
Furthermore, if complete sealing is desired, a metal thin film may be further laminated together with an adhesive.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the electrochromic display of the present invention, and FIG. It is a schematic plan view of the back side. fi+...Glass substrate (2)...Transparent electrode (3)...Insulator layer (4)...EC layer 1
51...ps layer (6)...counter electrode (
7)...Circular pattern (8)...Intermediate insulating layer (9)...Protective layer (101...Lead α1)...Lead extraction %15 +121...
Lead end patent applicant Toppan Printing Co., Ltd.

Claims (1)

[Claims] (1) Transparent IJJ, an electrochromic display in which at least an electrochemical coloring layer and a solid or semisolid proton donor layer are interposed between a display-side transparent electrode and a counter electrode provided on a transparent IJJ substrate. In the body, at least one of the transparent electrode on the display side and the counter electrode is formed as a separate electrode, and the solid or semi-solid proton donor layer is similarly separated according to the electrode, and a negative pattern is formed in the gap between the solid or semi-solid proton donor layers. -C, the solid or semi-solid proton donor layer and the insulating layer are formed by a printing method, a counter electrode is provided on the proton donor layer, and the counter electrode is An intermediate insulating layer is provided except for the lead extraction portions, and a conductive layer is provided which is converged from the plurality of lead extraction portions to an end portion on the transparent substrate to form a lead portion, and in addition, a protective layer is laminated. An electrochromic display body characterized by: