JPH0229720A - Method for manufacturing encapsulated electrochromic devices - Google Patents

Abstract

PURPOSE:To obtain an electrochromic element having sufficiently good appearance and reliability by forming a foamless sealing resin layer in a sealed electrochromic element. CONSTITUTION:The title electrochromic element is constituted of a substrate for the element, an electrochromic element formed thereon, a sealing resin layer coated on the electrochromic element, and a sealing substrate bonded onto said sealing resin layer, wherein said resin layer is regulated so as to contain no foams. In order to prevent mixing of foams during a sealing operation, the sealing resin is applied to the surface of the sealing substrate to obtain a resin layer having a circular or small width belt shape, upsetting the substrate quickly to let the sealing resin to contact spotly or linearly with the surface of the element substrate where an ECD has been formed previously. Thereafter, the sealing substrate is mounted slowly on the element substrate, and the sealing resin set or solidified. Thus, an electrochromic element having sufficiently good appearance and reliability is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to sealed electrochromic devices.

[Conventional technology]

Electrochromism is a phenomenon in which a reversible electrolytic oxidation or reduction reaction occurs when a voltage is applied, resulting in reversible coloring. Electrochromic (hereinafter abbreviated as EC) substances that exhibit such a phenomenon are used to produce electrolytic oxidation or reduction reactions by voltage manipulation. Create an EC element (hereinafter referred to as ECD) that changes color and erases color, and
Attempts to utilize C[l in light amount control elements (for example, anti-glare mirrors) and numeric display elements using seven segments have been made for more than 20 years. For example, an ECD (see Japanese Patent Publication No. 52-46098), which is made by sequentially laminating a transparent electrode film (cathode), a tungsten dioxide thin film, an insulating film such as silicon dioxide, and an electrode film (positive electrode) on a glass substrate, It is known as solid-state ECD.

When voltage is applied to this [ICD, tungsten dioxide (
wow) 'gIwA is colored blue. Thereafter, when a reverse voltage is applied to this ECD, -0, the blue color of the thin film disappears and it becomes colorless. The mechanism of coloring and decoloring has not been elucidated in detail, but it is believed that a small amount of water contained in the snow thin film and the insulating film (ion conductive layer) controls the coloring and decoloring of 10. The understood reaction formula for zero coloring is estimated as follows.

・H, O→ I+"+0H (-0, film-cathode side) (insulating film-anode side) OR--!48tO+'A 4(h↑10%eBy the way,
! A pair of electrode layers that directly or indirectly sandwich the IC layer are E
At least one of the layers must be transparent in order to show the coloring and decoloring of the C layer to the outside. Particularly in the case of a transmission type ECD, both materials must be transparent.Currently, transparent electrode materials include 5nOt, InzOz, and ITO (
SnO! Mixtures of In103 and In103), ZnO, etc. are known, but these materials have relatively poor transparency and must be made thin, and for this and other reasons, E
A CD is usually formed on a substrate such as a glass plate or a plastic plate, and an example of the structure of such an ECD is shown in FIG.

In FIG. 1, (A) is the lower transparent electrode, (B) is the lower transparent electrode, and (E) is the reduction coloring [IC layer (e.g. -0,
), CD) is an ion conductive layer, (C) is a reversible electrolytically oxidized N
(e.g. iridium oxide or hydroxide), respectively;
Basically, ECD can be achieved with just the laminated structure of (A) and (B).
As described above, these ECDs are formed on the element substrate (S). (R) is a sealing resin for the ECD, such as an epoxy resin, and (G) is a protective sealing substrate.

[Problem that the invention seeks to solve]

Conventionally, transmission type ECDs have had problems of poor appearance and reliability, and reflection type ECDs have had problems of poor reliability.

An object of the present invention is to improve the appearance and reliability of an ECD.

[Means for solving problems]

In order to solve the above problems, as a result of intensive research, we found that the sealing resin has a high viscosity, so it is easy to entrain fine air bubbles when mixing and stirring, and that air bubbles are formed in the sealing resin layer during the sealing process. If we find out that the cause of the problem is microscopic air bubbles that are easily caught and mixed into the sealing resin layer of the sealed ECD, and form a bubble-free sealing resin layer, the problem can be solved. The inventors have found a solution to the problem and have come up with the present invention.

Therefore, the present invention provides a sealed electrochromic device comprising an device substrate, an electrochromic device formed thereon, a sealing resin layer applied thereon, and a sealing substrate bonded thereon. The present invention provides an electrochromic device, characterized in that the sealing resin layer does not contain bubbles.

[Effect]

In order to prevent air bubbles from being mixed in during the sealing operation, the following method is preferable.

Method 1: After applying the sealing resin in a circular or strip shape onto the sealing substrate, quickly reverse the sealing substrate and apply EC in advance.
The sealing resin is brought into point or linear contact with the element substrate surface on which D is formed, and then the sealing substrate is slowly placed on the element substrate, and then the sealing resin is cured or solidified.

Method 2 = After applying the sealing resin in a circular or strip shape onto the element substrate on which the ECD has been formed in advance, the element substrate is quickly reversed and the sealing resin is brought into contact with the sealing substrate surface in a dot or straight line. After that, the element substrate is slowly placed on the sealing substrate, and then the sealing resin is cured or solidified.

The laminated structure of the ECD in the present invention is not particularly limited, but the structure of the solid type [ICD is as follows:
For example, ■4-layer structure such as ■ electrode layer / EC layer / ion conductive layer / electrode layer - 〇 5-layer structure such as electrode layer / reduction colored EC1i / ion conductive 11Fi / reversible electrolytic oxidation layer / IIT layer can give.

As the material of the transparent electrode, for example, SnO□, ln=0
3. ITO etc. are used. Such an electrode layer is
Generally, it is formed using vacuum thin film forming techniques such as vacuum evaporation, ion blating, and sputtering. (Reduction coloring property) As ECl1, generally used is 3, Mo5s, etc.

For example, silicon oxide, tantalum oxide, titanium oxide, aluminum oxide, niobium oxide, zirconium oxide, hafnium oxide, lanthanum oxide, magnesium fluoride, etc. are used as the ion-conducting layer. On the other hand, it is an insulator, but protons,
(H") and hydroxy ions (O"). Cations are required for the coloring and decoloring reaction of the EC layer, and it is necessary to include H9 ions and Li0 ions in the EC layer and other parts. (The 4 ions do not need to be ions from the beginning; it is sufficient that H''' ions are generated when a voltage is applied. Therefore, water may be contained instead of H4 ions. This water is very small. is sufficient,
Frequently, moisture that naturally enters from the atmosphere also discolors and fades.

The EC layer and the ion conductive layer may be placed either on top or on the bottom, and the EC layer is sandwiched between the ion conductive layer (which may also be an oxidation-colored IIC layer) and subjected to reversible electrolytic oxidation. A layer or catalyst layer may also be provided. Such layers include, for example, silidium oxide or hydroxide, nickel, chromium, vanadium, ruthenium, rhodium, etc. These substances are dispersed in an ion-conducting layer or a transparent electrode. The opaque electrode layer can be
It may also serve as a reflective layer, and metals such as gold, silver, aluminum, chromium, tin, zinc, nickel, ruthenium, rhodium, and stainless steel are used.

[Example 1] An ITO electrode layer was formed on the entire surface of a rectangular glass element substrate (S), and then an extraction part (F) for the upper electrode (A) and a lower electrode (B) were formed by photoetching or laser cutting. ) formed a groove between them. As a result, a take-out portion (F) and a rectangular lower electrode (B) isolated from the take-out portion (F) were formed. Note that these patterns may be directly formed by mask vapor deposition of ITO.A reversible electrolytic oxidation layer (C
), tantalum oxide layer (D) and tungsten oxide layer (E
) were formed in sequence. Finally, ITO is used as the upper electrode (A).
An ECD was produced by vapor-depositing. At this time, the ITO was formed so that one end was in contact with the extraction part (F) already formed on the substrate (S).

On the other hand, prepare a sealing jig (I) and place the element substrate (S) on it.
Then, after applying liquid sealing resin (R) made of epoxy resin on the sealing substrate (G) in a circular shape (see Figure 3a) or strip shape (see Figure 3b), seal it. Quickly reverse the stop substrate (see Figure 4a) and place the element substrate (S
) surface, contact the sealing resin at a point (see Figure 4b) or in a straight line, then slowly place the sealing substrate on the element substrate (Figure 4c), and apply the resin to the entire element surface. covered (
(See Figure 4d).

Eventually, the sealing resin will harden if left at room temperature or slightly heated, so after confirming that it has hardened, remove it from the jig and connect the external wiring LA, L to the lead-out portions of the upper and lower electrodes, respectively. After bonding, the ECD of this example is completed. When a coloring voltage (+1.35V) is applied to this ECD from the drive power supply (Su), the transmittance for light with a wavelength of 633n+* that is incident on the ECD decreases to 20% (after 10 seconds), and this transmittance is Even after the application was stopped, it was maintained for a while. This time, when a decoloring voltage (-1.35 V) was applied, the transmittance recovered to 70%. (After 10 seconds) This ECD is useful as a light control glass that can electrically control the amount of transmitted light.

[Example 2] An ITO electrode layer was formed on the entire surface of a rectangular glass element substrate (S), and then an extraction part (F) for the upper electrode (A) and a lower electrode (B) were formed by photoetching or laser cutting. ) formed a groove between them. As a result, a take-out portion CF) and a rectangular lower electrode (B) isolated from the take-out portion CF were formed. Note that these patterns may be directly formed by mask vapor deposition of ITO.A reversible electrolytic oxidation layer (C
), tantalum oxide 11 (D), and tungsten oxide layer (E) were formed in this order. I! After that, ITO was deposited as a lower electrode (A) to fabricate an 11CD. At this time ITO
was formed so that one end was in contact with the take-out portion (F) already formed on the substrate (S).

Here, a conductive clip made of phosphor bronze with a U-shaped cross section (
Two H) were prepared, and external wiring a (LA) or (Ll) was connected to each with solder or conductive adhesive. The two clips (H) were attached to the electrode lead-out portions of the element substrate (S), so that the clips (H) crimped the upper and lower electrode lead-out portions.

The shape and dimensions of the conductive clip (H) were set so that the sealing substrate (G) could be positioned and the non-display area around the ECr1 could be masked.

On the other hand, a sealing jig (r) is prepared, and an element substrate (S
) Place a smaller rectangular glass sealing substrate (G). Then, after applying a liquid sealing resin (R) made of epoxy resin in a circular or narrow strip shape onto the element substrate (S), the element substrate is quickly reversed and the sealing resin is dotted on the surface of the sealing substrate (G). Alternatively, the element substrate was brought into linear contact, and then the element substrate was slowly placed on the sealing substrate to cover the entire element surface with the resin. The sealing resin will eventually harden if left at room temperature or slightly heated, so after confirming the hardening, it was removed from the jig and the ECD of this example (see FIG. 2) was obtained.

Note that it is convenient if the sealing jig is made of Teflon or silicone rubber, since the sealing resin will not stick to the jig after hardening.

A coloring voltage (+1.
When a voltage of 35 V) was applied, the transmittance for light with a wavelength of 633 cm incident from the ECU +□ decreased to 20% (after 10 seconds), and this transmittance was maintained for a while even after the voltage application was stopped. This time, when a decoloring voltage (-1.35 V) was applied, the transmittance recovered to 70%. (After 10 seconds) [Effects of the Invention] As described above, according to the present invention, since a sealing resin that does not contain air bubbles is used, the transmission type EC [1] has good appearance and reliability. A device can be obtained, and a highly reliable device can be obtained in the case of a reflective ECD.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view showing an example of an ECD. FIG. 2 is a schematic vertical sectional view of an ECD according to a second embodiment of the present invention. 3a and 3b are schematic plan views showing the applied shape of the sealing resin in Example 1. FIG. 4a to 4d are schematic vertical cross-sectional views showing the sealing process in Example 1. FIG. Figures 5a to 5c are schematic vertical sectional views showing a conventional sealing process. Fig. 1 [Explanation of symbols of main parts] ECD... Electrochromic S child S...
Element substrate G...Sealing substrate R...Sealing resin H...Conductive clip ■...Sealing jig 3rd figure

Claims (1)

[Claims] In a sealed electrochromic element comprising an element substrate, an electrochromic element formed thereon, a sealing resin layer applied thereon, and a sealing substrate bonded thereon, the sealing An electrochromic element characterized in that the resin layer does not contain air bubbles.