JPS63259517A - Method for manufacturing electrochromic display elements - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing an electrochromic display element (hereinafter abbreviated as ECD) that exhibits reversible color development and fading upon application of voltage. More specifically, the present invention relates to a method of manufacturing an ECD element having no ionic conductivity between cells of the ECD by separating the electrolyte layer of an ECD displaying a dot matrix into a portion to be colored and decolored and a portion not to be colored. ' (Prior art and problems to be solved by the invention) It is a display element that has no viewing angle dependence and is easier to see than liquid crystal, has a memory function, and can be driven at low voltage. It has the following characteristics.

In recent years, research has been carried out on dot matrix display of ECU (ECU) elements consisting of a large number of cells.

In this case, there are two methods as follows depending on the method of installing the electrodes.

(11) A method in which electrodes are taken out individually from each cell and a current is passed through the electrodes connected to the cells that are to be colored or erased.

(2) One of the anode or cathode is arranged in a line in the horizontal direction on the surface of the ECD element, and the other 'rFL pole is arranged in a line in the vertical direction on the back surface of the ECD element, and the point where the two electrodes intersect A method in which cells are placed on top and electrodes for passing current are selected from among the electrodes arranged vertically and horizontally to determine which cells will be colored and faded.

Since method (1) above has the disadvantage that it is not possible to reduce the size of each cell, research is underway to adopt method (2) above. But something like this (2)
In this method, since current flows to adjacent cells through the electrolyte, a cross-talk phenomenon occurs in which even cells adjacent to the cell to be colored or bleached are colored or bleached.

In order to prevent such a loss talk phenomenon, the following method is adopted. That is, after forming a transparent conductive film on a substrate, an insulating layer made of ceramics is clean-printed except for the cell part, and then an electrocomic film (hereinafter referred to as ECIII), an electrolyte layer, and a counter electrode are formed on the cell part. The method is to form. However, such a method cannot be applied to a relatively large dot matrix display 0E.
Although suitable for CD devices, small ECD devices have problems with positional accuracy and are difficult to manufacture.

(Means for Solving the Problem) In view of the above problems, the present inventors separated the electrolyte layers of adjacent cells to improve ionic conductivity even in a relatively small dot matrix display 0ECD element. I've been researching ways to get rid of it.

As a result, by using a mixture of a photopolymerizable substance and an electrolyte as the electrolyte layer, and then irradiating with light to polymerize the photopolymerizable substance present in the gap between each cell,
The inventors have found that the above object can be achieved and have completed the present invention.

That is, in manufacturing an electrochromic display element of the present invention, which includes a cell in which a light-transmitting substrate, a transparent conductive film, an electrochromic film, an electrolyte layer, a counter electrode, and a light-transmitting substrate are laminated in this order, A transparent conductive film and an electrochromic film are formed on one optically transparent substrate, and a counter electrode is formed on the other optically transparent substrate,
Next, a mixture of a photopolymerizable substance and an electrolyte was applied to at least one of the two light-transparent substrates on the side on which the transparent conductive film and the electrochromic film or the counter electrode were formed. After that, the side on which the transparent conductive film and the electrochromic film or the counter electrode of both the light-transmitting substrates were formed,
A method for producing an electrochromic display element, which comprises gluing both light-transmitting substrates together so that they are on the inside of each other, and then irradiating the substrate with light to polymerize the photopolymerizable material in the gap between each cell. .

Further, the present invention provides a method for manufacturing an electrochromic display element consisting of a cell in which a light-transmitting substrate, a transparent conductive film, an electrochromic film, an electrolyte layer, a counter electrode, and a light-transmitting substrate form a laminated structure in this order. , - a transparent conductive film and an electrochromic film are deposited on one optically transparent substrate, a counter electrode is formed on the other optically transparent substrate, and then at least one of the two optically transparent substrates is formed. A mixture of a photopolymerizable substance and an electrolyte is applied to the side of one of the light-transmitting substrates on which the transparent conductive film and electrochromic film or counter electrode are formed, and then light is irradiated to form a mixture that exists in the gaps between each cell. It is characterized by polymerizing a photopolymerizable substance, and then gluing both optically transparent substrates together so that the sides of both optically transparent substrates on which the transparent conductive film and the electrochromic film or the counter electrode are formed are on the inside of each other. The present invention also provides a method for manufacturing an electrochromic display element.

The cell of the ECD element according to the present invention has a laminated structure in which the light-transmitting substrate, transparent conductive film, EC film, electrolyte layer, counter electrode, and light-transmitting substrate are arranged in this order.

As for the light-transmitting substrate, transparent conductive film, EC film, counter electrode, and electrolyte used in the present invention, conventionally known ones can be arbitrarily employed. For example, as a light transmitting substrate, the light 1
There are no particular restrictions on the material as long as it transmits light that polymerizes the polymerizing substance, but generally a glass plate, an acrylic resin plate, or the like is used. In addition, as for the transparent conductive film, known ones can be used, such as indium oxide-tin oxide (
Oxide semiconductor thin films such as ITO), tin oxide, zinc oxide, titanium oxide, cadmium oxide, and cadmium tin oxide, or thin films of gold, silver, etc. having a thickness of 50 angstroms or less are preferably used. As for the EC film, any known material can be used; for example, amorphous tungsten oxide is the most typical, but other materials that have recently been studied as EC materials, such as organic dyes, metal complexes, transition metal compounds, and organic polymers, can be used. Adopted as appropriate. Furthermore, for the counter electrode, known ones can be used, such as indium oxide, indium oxide-tin oxide film (ITO film), metal, amorphous tungsten oxide, iron complex, transition metal compound-carbon sintered body, and manganese oxide. Other examples include:

Note that the counter electrode in the present invention includes not only the well-known ones described above but also those made of two layers of an EC film and a transparent conductive film and functioning as an electrode.

As the electrolyte in the present invention, any known electrolyte can be used without any restriction. For example, a system of propylene carbonate or butyllactone and lithium perchlorate; glycerin;
Mention may be made of electrolytes such as the urea and para-toluenesulfonic acid systems. Further, in the present invention, it is preferable to use a polymer having an ion exchange group, for example, an ion exchange rate, as an electrolyte because the response speed and contrast ratio of the resulting ECD device are improved.

Hereinafter, a typical method of manufacturing an ECD element according to the present invention will be specifically explained with reference to the accompanying drawings, but the present invention is of course not limited to the method described below.

First, a transparent conductive film 2 is formed on the surface of one of the two light-transmissive substrates 1 and 1 by a known method such as sputtering. The EC film 3 is formed by a known method such as vacuum evaporation or sputtering.
Next, in order to arrange the cells in a donmatrix arrangement, unnecessary portions of the transparent conductive film 2 and the EC film 3 are removed so that they form lines or strips parallel to each other in the horizontal or vertical direction. The unnecessary portion is a portion that becomes a gap between each cell of the ECD element. As a method for removing unnecessary portions, a known method using a photoresist can be adopted. That is, - A photoresist is applied to the surface of the EC film, a photomask is placed on it, and then exposed to light.Then, the uncured photoresist is removed and the transparent conductive film and the EC film are etched with an etching solution. Then, the hardened photoresist is peeled off to obtain a transparent conductive film 2 and an EC film 3 in the form of lines or bands parallel to each other.

A counter electrode 4 is formed on the surface of the other light-transmissive substrate l° by the same method as described above. Then, in order to obtain a dot matrix arrangement on the counter electrode side, lines parallel to each other are formed in a direction orthogonal to the lines or strips of the transparent conductive film and the EC film. The method can be carried out in the same manner as the method using the photoresist described above.

In this way, the transparent conductive film 2 and the ECC 20 are formed as lines or strips parallel to each other in the lateral direction on one light-transmitting substrate 1, and the counter electrode 4 is formed on the other light-transmitting substrate 1'. are formed as lines or strips parallel to each other in the longitudinal direction.

Next, a mixture 5 of an electrolyte and a photopolymerizable substance is applied to the side of the light-transmitting substrate 1 obtained above on which the transparent conductive film 2 and the ECC 20 are formed by a method such as screen printing.
In the present invention, the photopolymerizable substance present between the cells is later polymerized. On the other hand, the photopolymerizable material present at the cell location remains unpolymerized and has no effect on the operation of the ECD; therefore, the application of a mixture of photopolymerizable material and electrolyte is effective in discriminating between the cells and the cells. It can be applied to the entire surface. The mixture 5 of electrolyte and photopolymerizable substance may be applied to the light-transmitting substrate 1 as described above, or it may be applied to the light-transmitting substrate 1''. There is no problem in applying it to a sexual substrate.

As the photopolymerizable substance used in the present invention, known substances that polymerize under visible light, ultraviolet rays, infrared rays, etc. can be used without any limitations. In the present invention, a photopolymerizable substance consisting of a polymerizable vinyl monomer, a photosensitizer, and a photopolymerization accelerator is preferably used. The photopolymerizable substance used in the present invention is
It is preferable that the two light-transmitting substrates constituting the ECD element be bonded to each other after polymerization.

In order to obtain a photopolymerizable substance that functions as such an adhesive, it is preferable to select a polymerizable vinyl monomer containing an acryloyl group or a methacryloyl group.

Specific examples of polymerizable vinyl monomers that can be suitably used in the present invention are as follows.

For example, methyl methacrylate; ethyl methacrylate; isopropyl methacrylate; hydroxyethyl methacrylate; tetrahydrofurfuryl methacrylate;
Glycidyl methacrylate; and monofunctional vinyl monomers such as these acrylates; 2.2-bis(methacryloxyphenyl)propane; 2
,2-bis(4-(3-methacryloxy)-2-hydroxypropoxyphenyl)propane; 2,2-bis(4
aliphatic difunctional vinyl monomers such as ethylene glycol dimethacrylate; diethylene glycol dimethacrylate; triethylene glycol dimethacrylate; and acrylates thereof; : Trifunctional vinyl monomers such as trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate and their acrylates: Tetrafunctional vinyls such as pentaerythritol tetramethacrylate and pentaerythritol tetraacrylate Monomers and the like can be mentioned.

Specific examples of photosensitizers suitably used include benzyl, camphorquinone, α-naphthyl, acetonaphcene, P,P'-dimethoxybenzyl, P,P"-dichlorobenzyldiacetyl, and pentanedione. , l, 2-phenanthrenequinone, 1,4-phenanthrenequinone, 3,4-phenanthrenequinone,
9. α of 10-phenanthrenequinone, naphthoquinone, etc.
-Diketones; Benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether; acetoin benzophenone, P-chlorobenzophenone, P-
Examples include benzophenones such as methoxybenzophenone.

Furthermore, examples of the photopolymerization accelerator include N,N-dimethylaniline, N,N-diethylaniline, and N.

N-di-n-butylaniline, N,N-dibenzylaniline, N,N-dimethyl-p-)luidine, N,N
-diethyl-p-)luidine, N, N-dimethyl-m
-) Tertiary amines such as luidine can be mentioned.

These photosensitizers and photopolymerization accelerators may be used in an amount of 1 to 5% by weight of O, OO based on the polymerizable vinyl monomer. The mixing ratio is 20:80-70:
Furthermore, the range of 0 to 60:40 is preferable because the photopolymerizable substance exhibits ion conductivity when unpolymerized, and can effectively block ion movement after polymerization. preferred.

After this, two methods are adopted in the present invention.

In one method, after applying a mixture 5 of an electrolyte and a photopolymerizable substance, light is irradiated using a photomask to polymerize the gaps between the cells, and then the light-transmitting substrates 1 and 1 are
This is a method in which the EC film and the counter electrode are attached on the inside.

In the other method, immediately after applying the mixture 5 of an electrolyte and a photopolymerizable substance, the light-transmitting substrate 1 and the 1° are bonded together.
In this method, the photopolymerizable material in the gap between the cells is then polymerized by irradiation with light.

The second method will be explained in more detail below.

A light-transmissive substrate 1 coated with a mixture 5 of an electrolyte and a photopolymerizable substance and a light-transmissive substrate l' on which a counter electrode is formed are pasted together so that the coated surface and the counter electrode 5 are on the inside. Then, a laminated structure of the light-transmitting substrate 1, the transparent conductive film 2, the EC film 3, the mixture 5 of electrolyte and a photopolymerizable substance, the counter electrode 4, and the light-transmitting substrate 1' is formed.

In the present invention, furthermore, light is irradiated from both sides of the transparent substrate l and 1° to remove the transparent electric shock gi2, the EC film 3, and the counter electrode 4, which exist in the gap between each cell. At this time, EC
When a light-opaque material is used as the film and the counter electrode, the EC film and the counter electrode function as a photomask, and the line or band-shaped EC film and the line or band-shaped counter electrode that intersects with it. Polymerization of the photopolymerizable substance does not occur at the intersection 5'', that is, this intersection becomes a dot matrix array cell.

Examples of the above-mentioned light-opaque materials include tungsten oxide, iridium oxide, vanadium oxide, etc. that are opaque to ultraviolet rays, and metals, Examples include manganese dioxide, iron complexes, transition metal oxide-carbon sintered bodies, and the like. If the EC film and the counter electrode are not light-opaque, a photomask may be used to polymerize only the gap between each cell.

(Effect) According to the method of the present invention, the EC of a dot matrix array
Ion conductivity between each cell in the D element can be eliminated. That is, it is possible to polymerize only the photopolymerizable substance present in the gap between each cell, thereby blocking the movement of ions between the cells. Moreover, since the photopolymerizable substance is not polymerized in the cell portion, the performance of the ECD element will not be affected in any way.

Therefore, according to the method of the present invention, it is possible to form an insulating layer between cells and an electrolyte layer at the same time, compared to a method in which an insulating layer between cells is formed in advance and then an electrolyte layer is formed. be. Moreover, crosstalk is prevented from EC.
It is possible to manufacture D elements.

Furthermore, according to a method in which light is irradiated after attaching light-transmitting substrates to each other, an ECD element with high mechanical strength can be manufactured because the photopolymerizable substance bonds the light-transmitting substrates together. Furthermore, in the above method, if a light-opaque material is used for the EC film and the counter electrode,
It is possible to polymerize the photopolymerizable substance present in the gap between cells without using a photomask. Therefore, compared to the method using a photomask, this method is simpler, and there is no shift in the portion to be polymerized, and the positional accuracy of the polymerized portion can be improved.

As described above, according to the method of the present invention, the movement of ions between cells can be prevented in an extremely simple manner, and the occurrence of crosstalk phenomenon can be prevented.

Incidentally, the method of the present invention is based on a dot matrix array ECD.
It can be applied not only to manufacturing elements but also to manufacturing a plurality of cells other than single or dot matrix arrays.

The present invention will be explained below according to Examples, but the present invention is not limited to these Examples.

Example 1 An ECD was produced according to the following steps. A transparent conductive film (InzO containing 5% Snug) was placed on a light-transmissive glass substrate.
3000 films were created by sputtering.'z).

Next, WO3 was deposited by 2000 people on a light-transmitting substrate provided with a transparent conductive film by vacuum deposition to form an EC film.

Next, in order to create electrodes in a dot matrix array, a photoresist was applied using a spinner onto a light-transmitting substrate with a transparent conductive film and an EC film by photoetching.
It was applied to a thickness of 0 μm and dried.

Thereafter, a photomask for forming electrodes was placed on it, and after baking by ultraviolet exposure, the resist was peeled off. Next, the transparent conductive film and the EC film were etched using an acidic etching solution, the resist was removed, and electrodes were created.

In addition, the counter electrode was sputtered with 1000 iridium oxide.
It was created using the same photo-etching process.

Next, by screen printing, a mixture of a photopolymerizable substance and an electrolyte was applied to the side on which the EC film had been formed, and the opposing electrode sides were bonded together.

40 parts by weight of polyester acrylate, 50ffi of 1,3-butanediol diacrylate as photopolymerizable substances
ff, 5 parts by weight of benzoin, and 5 parts by weight of N,N-dimethylaniline, and polystyrene sulfonic acid having a molecular weight of 50,000 was used as the electrolyte. The mixing ratio of the photopolymerizable substance and the electrolyte was 40:50 by weight.

Next, we applied ultraviolet light with a wavelength of around 280nm from a metal halide lamp to the glued together, and applied it to 100W/a! It was irradiated for 10 seconds at a power of 1 liter to deactivate the ion exchange function and at the same time adhere the parts other than the display part.

Next, the periphery of the ECD element was fixed with a sealant.

1 containing an ultraviolet absorber on the rain upper surface of both optically transparent substrates.
A 00 μm transparent film was laminated to improve weather resistance.

The obtained ECD element was in good condition with no crosstalk phenomenon observed.

Example 2 The same procedure as in Example 1 was performed up to the point where the mixture of photopolymerizable substance and electrolyte was applied to the side on which the EC membrane was laminated. After that, a photographic negative film with exposed cell parts but unexposed cell gap parts was fixed as a photomask on the side to which the photopolymerizable substance and electrolyte mixture was applied, and ultraviolet rays of a metal halide lamp having a wavelength of around 28 Onm were fixed. using
The photopolymerizable material located between the cells was polymerized.

On the other hand, a light-transmissive substrate on which a counter electrode was formed in the same manner as in Example 1 was laminated to the substrate obtained above, and the periphery of the ECD element was fixed with a sealant.

1 containing ultraviolet absorption outside 1 on the upper surface of the both light-transmissive substrates
A light transmitting film of 0.00 ttm was laminated to improve weather resistance.

The obtained ECD element was in good condition with no crosstalk phenomenon observed.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing the structure of an ECD element obtained by the method of the present invention. In the figure, 1 and 1'' are light-transmissive substrates, 2 is a transparent conductive film, and 3
4 is an EC film, 4 is a counter electrode, 5 is a mixture of a photopolymerizable substance and an electrolyte, 5'' is a portion that is polymerized by light irradiation, and 5'' is a portion that is not polymerized by light irradiation.

Claims (2)

[Claims] (1) In manufacturing an electrochromic display element consisting of a cell in which a light-transmitting substrate, a transparent conductive film, an electrochromic film, an electrolyte layer, a counter electrode, and a light-transmitting substrate are laminated in this order, one of the A transparent conductive film and an electrochromic film are laminated on a light-transparent substrate, a counter electrode is formed on the other light-transparent substrate, and then,
After applying a mixture of a photopolymerizable substance and an electrolyte to the side on which the transparent conductive film and the electrochromic film or the counter electrode of at least one of the above two light-transmissive substrates are formed, both light-transmissive substrates are coated. The transparent conductive film and the side on which the electrochromic film or counter electrode of the transparent substrate are formed are on the inside of each other, and then,
A method for producing an electrochromic display element, which comprises irradiating light to polymerize a photopolymerizable substance in the gap between each cell. (2) In manufacturing an electrochromic display element consisting of a cell in which a light-transmitting substrate, a transparent conductive film, an electrochromic film, an electrolyte layer, a counter electrode, and a light-transmitting substrate are laminated in this order, one of the A transparent conductive film and an electrochromic film are laminated on a light-transparent substrate, a counter electrode is formed on the other light-transparent substrate, and then,
A mixture of a photopolymerizable substance and an electrolyte is applied to the side on which the transparent conductive film and the electrochromic film or the counter electrode are formed on at least one of the above two light-transmissive substrates, and then light is irradiated. The photopolymerizable substance existing in the gap between each cell is polymerized, and then both light-transmitting substrates are heated so that the sides on which the transparent conductive film and the electrochromic film or counter electrode are formed are on the inside of each other. A method for manufacturing an electrochromic display element, characterized by laminating transparent substrates together.