JPH0118429B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an electrochromic body layer made of at least a transition metal oxide between a transparent patterned electrode and a counter electrode, and an insulator having a negative pattern for the display portion of the electrochromic body layer. The present invention relates to an electrochromic display comprising a layer and an electrolyte.

Based on the conventional electrochromic display body shown in FIG. A display electrode 2 is formed in a pattern as shown in FIG. Further, an electrolyte layer 5 is formed thereon, and a reversible oxide layer 6 serving as a counter electrode and a current collector layer 7 are provided. Note that 8 in the figure is a protective layer made of insulating cured resin or the like.

Conventionally, the electrochromic layer is deposited on the display electrode 2 using a mask, or instead of a mask, a negative pattern of photoresist or printing ink is provided on the display electrode 2, and the photoresist or printing ink is removed after vapor deposition. It is provided by a so-called lift-off method in which an electrochromic layer is left in a pattern. Then, the electrolyte layer 5 is laminated thereon, but at this time, if the display electrode 2 and the electrolyte layer 5 come into contact with each other in the non-display area, an abnormality occurs that is thought to be caused by the reduction of the display electrode 2 or the electrolyte layer 5. The lifespan of the display body due to repeated color development and fading is shortened. In order to prevent this, an insulating layer is provided in the non-display area where the electrochromic layer 4 is not provided.

However, this lamination process requires a high degree of skill in registering the electrochromic layer 4 in the display area and the insulator layer 3 in the non-display area.

If the register is misaligned at this time, the display electrode 2 will be exposed and come into contact with the electrolyte layer 5, resulting in a blackened part 9 that is considered to be reduction of the display electrode 2 or deterioration of the electrolyte.
will occur. On the other hand, if the insulating layer 3 overlaps the electrochromic layer 4, the electrochromic layer 4 in this area develops color when a voltage is applied, but does not disappear when a reverse voltage is applied, resulting in colored edges. This results in a pattern display having portions 10, making it impossible to obtain a good display. Further, as shown in FIG. 1b, an insulating layer 3a is formed on the display electrode 2 in a negative pattern for the display part, and then
In an electrochromic display body in which the electrochromic body layer 4 is vapor-deposited without patterning, and the electrolyte layer 5 is further provided, coloring also occurs in the non-display areas, and as described above, the non-display areas do not fade and are bordered. Part 11
This would result in a pattern display that was similar to the previous one.

In the present invention, in order to prevent the aforementioned blackening and edge fading, the peripheral non-display area of the electrochromic body layer is sandwiched between two insulating layers having a negative pattern with respect to the pattern of the display area, and the electrochromic body layer is This improves the electrical insulation state of the peripheral non-display area.

An explanation will be given based on an embodiment of the present invention shown in FIG. 2 of the drawings.A display electrode 2 made of a transparent conductive film such as indium oxide or tin oxide is provided on one side of a transparent substrate 1 made of glass, plastic, etc. alms,
After providing an insulator layer 3 with a negative pattern corresponding to the pattern of the display part on the display electrode 2, an electrochromic body layer 4 serving as a display body is provided in the display part and the non-display part, and further 3 The same insulator layer 12 is again provided in a negative pattern with respect to the pattern of the display part, and after sandwiching the non-display part of the electrochromic body layer 4, an electrolyte layer 5 is applied, and a reversible oxidation film is applied thereon to form a counter electrode. This is an electrochromic display in which a material layer 6 and a current collector layer 7 are provided, and then a protective layer 8 is laminated to cover the entire surface. Regarding the electrolyte layer 5 and insulator layers 3 and 12 that constitute this, the electrolyte layer is made of titanic acid, stannic acid, antimonic acid, antimonic acid, zirconic acid, niobic acid, tantalic acid, silicic acid, etc. One type or a mixture of two or more types can be selected. These materials are sometimes called hydrated metal oxides or metal oxide hydrates, and are often expressed by the general formula (MxOy.ZH ₂ O: x, y, z are integers or fractions). Of course, this is different from simply mixing oxides such as titanium oxide, tin oxide, antimony oxide, zirconium oxide, tantalum oxide, and niop oxide with water from the outside.

These above-mentioned materials are white powders that are effective in increasing the whiteness of the base, and they themselves exhibit high proton conductivity, with a resistance value of 1×10 ⁴ to 1×
The resistance is as low as 10 ⁵ Ω/cm, and when these are added, the color development response does not worsen, and on the contrary, both the response speed and the color development density are improved. Powders of titanic acid, stannic acid, antimonic acid, zirconic acid, niobic acid, tantalic acid, etc. maintain their proton conductivity even when a small amount of binder used in printing inks and coating compositions is added. These coated and cured layers are useful as solid electrolytes in electrochromic displays.

As a binder, the vapor pressure at 20℃ is 0.1
Polyhydric alcohols, water-soluble polymers, or aqueous emulsion-type polymers that are liquids at mmHg or less are preferable in order to maintain proton conductivity. Further, as a solvent for forming an ink or coating composition, it is preferable to use water or a water-soluble solvent such as a lower alcohol or a lower ketone.

Such a solid electrolyte has the advantage that it can be formed by printing, for example, screen printing or various coating methods, and can be applied to a wide range of thicknesses. For example, 2 to 2000μm can be used, especially 50 to 2000μm.
A thickness of 400 μm seems preferable.

Liquid electrolytes include a sulfuric acid aqueous solution, sulfuric acid-added glycerin, propylene carbonate with lithium perchlorate added, and the present invention can be applied to electrochromic displays other than solid electrolyte types.

Furthermore, any material that exhibits an electrochromic phenomenon other than tungsten oxide as shown in the following examples may be used as the material for the electrochromic body layer, such as transition metal oxides such as molybdenum oxide, titanium oxide, iridium oxide, etc. A mixture of these or an organic electrochromic material such as a viologen derivative fixed on an organic film may be used. The present invention includes these.

Next, regarding the insulator layer 3, it is basically preferable to use a transparent insulating resin, but a coloring material can also be added thereto.

The basic component is preferably a cured resin that does not contain a solvent, such as an oxidative polymerization type resin, an ultraviolet curable resin, or a crosslinked polymerization type resin, and more preferably a resin that is suitable for printing and coating in an uncured state. Colorants that can be added to the insulator layer include those that affect the insulation,
In other words, materials that degrade insulation cannot be used.
For example, carbon black, which is a good conductor, has poor insulation properties and cannot be used as a coloring material.

As the coloring material used in the present invention, it is preferable to use a pigment with good insulation properties, and by using a screen printing ink containing such a pigment, an insulator layer showing good insulation properties can be obtained.

Note that the insulating layer can also be formed by a method other than printing and coating, such as vapor deposition or sputtering of an insulating inorganic or organic material.

Silicon dioxide (SiO ₂ ), magnesium fluoride (MgF ₂ ), cerium oxide (Ce ₂ O ₃ ), silicon nitride (Si ₃ N ₄ ), tantalum oxide (Ta ₂ O ₅ ), Examples include yttrium oxide (Y ₂ O ₃ ), silicon monoxide (SiO), and zinc sulfide (ZnS).

The electrochromic display body of the present invention has an electrochromic body layer sandwiched between two insulating layers to isolate a transparent display electrode from a liquid or solid electrolyte layer. It is possible to prevent blackening of the electrode due to reduction. Also,
By isolating the peripheral non-display portion of the electrochromic body layer from the display electrode and the electrolyte, it is difficult to cause a fringing phenomenon due to the remaining part of the electrochromic body layer. In addition, by adding a coloring agent to the insulating layer to make it opaque, even if some edging occurs in the peripheral non-displayed area of the electrochromic layer, the colored edging area will be more noticeable than the overlap of the insulating layer. You can also make it invisible.

Furthermore, since the two insulating layers that sandwich the electrochromic body layer have a negative pattern with respect to the display area, there is no need to pattern the electrochromic body layer, which eliminates problems such as misregistration. There is.

The invention will be explained in more detail in the following examples.

[Example 1] Transparent electrodes made of indium oxide were provided in a pattern on a glass substrate, and a non-display area on the transparent electrodes was screen printed using Toyo Ink Mfg. Co., Ltd. (trade name: SS).
-Product name of screen printing ink made by Toyo Ink Manufacturing Co., Ltd., which is made by adding pigment to 25000 ink medium.
SS25-611 (white), SS25-262 (yellow), SS25-911
(ink) was mixed and toned and printed using a screen printing method to form an insulating layer.

Next, tungsten oxide is deposited on the display area and the surrounding non-display area to a thickness of about 4500 Å by vacuum evaporation using an electron beam heating method, and then the above-mentioned insulating layer is printed again on the non-display area above it, and the surrounding area is coated with tungsten oxide. The tungsten oxide film in the non-display area was sandwiched.

Next, as a solid electrolyte layer, antimonic acid, glycerin, and water were kneaded in a weight ratio of 5:1.2:0.5 to form an ink, which was applied to a film thickness of approximately 300 μm using a screen printing method. After drying, a carbon-based Conductive paste manufactured by Fujikura Kasei Co., Ltd. Product name Dotite
A mixture of 10 parts of XC-74 and 3 parts of Bruciare Blue was printed and laminated using a screen printing method to form a counter electrode that can be reversibly oxidized, and an Ag-based conductive paste manufactured by Fujikura Kasei Co., Ltd. (trade name: Dotite) XA-167
were laminated to form a current collector layer, and then an epoxy resin manufactured by Nagase Ciba Co., Ltd. under the trade name Araldite Standard was provided as a protective layer and polymerized and cured to produce a display. When a voltage of ±1.57V was applied to this at a cycle of about 1 second, a bright blue color was obtained with no remaining edges or blackening.

[Example 2] As the ink for forming an insulator layer in Example 1, Toyo Ink Manufacturing Co., Ltd., which added a pigment to Ink Medium (trade name: SS-25000, manufactured by Toyo Ink Manufacturing Co., Ltd.) was used for the insulating layer on the display electrode. ) Screen printing ink (trade name: SS25-611 (white) and SS25-262 (yellow)) is used as an insulating layer to be applied on the tungsten oxide film (trade name: Toyo Ink Mfg. Co., Ltd.). SS
- Screen printing was performed using a transparent insulating layer of 25,000 yen, and a voltage of 1.57 V was applied. Example 1
Similar good results were obtained.

[Example 3] Transparent electrodes made of indium oxide were provided in a pattern on a glass substrate, and Toyo Ink Manufacturing Co., Ltd. (trade name: SS) was printed on the non-display area by screen printing.
-25000 ink medium mixed with pigmented Toyo Ink Manufacturing Co., Ltd. trade name SS25-262 (yellow) was used to print using a screen printing method to form an insulating layer.

Next, tungsten oxide is deposited on the display area and the peripheral non-display area to a thickness of approximately 4500 Å using a vacuum evaporation method using an electron beam heating method, and then the above-mentioned insulating layer is printed again on top of it, and the peripheral non-display area is A tungsten oxide film was sandwiched between the two.

Next, as a solid electrolyte layer, antimonic acid, glycerin, and water were kneaded in a weight ratio of 5:1.2:0.5 to form an ink, and the color was adjusted by adding pigment brand name Chroma Toner YZ manufactured by DuPont in the United States, and the screen printing method was used. After drying, a carbon conductive paste made by Fujikura Kasei Co., Ltd. (trade name: Dotite A counter electrode that can be reversibly oxidized was printed and laminated, and an Ag-based conductive paste was further laminated to form a current collector layer, and then an epoxy resin (trade name: Araldite Stanbird, manufactured by Nagase Ciba Co., Ltd.) was used as a protective layer. was prepared and polymerized and cured to produce an electrochromic display.

When a voltage of 1.57V is applied to this, a blue color is obtained on the yellow base consisting of the insulator layer and solid electrolyte. In addition, good results were obtained with no remaining edges or blackening.

[Example 4] As the insulator layer ink used in Example 1, glass additives 1 to 2 were mixed and toned with ultraviolet curable ink Daikyure SSP Yellow manufactured by Dainippon Ink and Chemicals Co., Ltd. on a transparent electrode. % addition, printing by screen printing method and hardening, then tungsten oxide is applied by vacuum evaporation method using electron beam heating method.
The display area and the surrounding non-display area are vapor-deposited to a film thickness of 4500 Å, and then Toyo Ink Mfg. Co., Ltd.'s product name SS-25000 Ink Medium is printed on the non-display area using a screen printing method to make the surrounding area invisible. A tungsten oxide film was sandwiched between the parts. Next, when a voltage of 1.57V was applied to a display body in which a solid electrolyte layer, a reversible oxidation material layer, and a current collector layer were laminated by a screen printing method, good results were obtained.

[Brief explanation of drawings]

FIG. 1 shows an example of a conventional electrochromic display, FIG. 1a is a schematic sectional view showing a defect due to misregistration of the insulator layer, and FIG. FIG. 3 is a schematic cross-sectional view showing the drawbacks of an example in which no clamping is performed. FIG. 2 is a schematic cross-sectional view showing an example of the electrochromic display of the present invention. DESCRIPTION OF SYMBOLS 1... Transparent substrate, 2... Display electrode, 3... Insulator layer, 4... Electrochromic body layer, 5...
Electrolyte, 6... Reversible oxidation material layer, 7... Current collector layer, 8... Protective layer, 9... Blackened part, 10... Colored part, 11... Edged part, 12... Insulator layer.

Claims (1)

[Scope of Claims] 1. In an electrochromic display body in which at least an electrochromic body layer and an electrolyte layer are interposed between a display electrode and a counter electrode provided on a transparent substrate, the electrochromic body An electrochromic display body characterized in that a peripheral non-display area of a layer is sandwiched between two insulating layers having a negative pattern with respect to a pattern of a display area. 2. The electrochromic display according to claim 1, wherein at least one of the insulating layers sandwiching the electrochromic layer is a white or colored opaque layer.