JPH07104529B2 - Encapsulated electrochromic device and method of manufacturing the same - Google Patents

Description

The present invention relates to a sealed electrochromic device.

[Conventional technology]

The phenomenon in which a reversible electrolytic oxidation or reduction reaction occurs when a voltage is applied to cause reversible coloring is called electrochromism. By using an electrochromic (hereinafter abbreviated as EC) substance that exhibits such a phenomenon, an EC element (hereinafter abbreviated as ECD) that is colored and decolored by voltage operation is made, and this ECD is used as a light amount control element (for example, a protective element). Attempts have been made for more than 20 years to use it for a numerical display device using a dazzling mirror) or 7 segments. For example, an ECD (see Japanese Examined Patent Publication No. 52-46098), which is formed by sequentially laminating a transparent electrode film (cathode), a tungsten trioxide thin film, an insulating film such as silicon dioxide, and an electrode film (anode) on a glass substrate, is all solid. Known as type ECD. When a voltage is applied to this ECD, the tungsten trioxide (WO ₃ ) thin film is colored blue. Then, when a reverse voltage is applied to this ECD, the blue color of the WO ₃ thin film disappears and becomes colorless. The mechanism of coloring / decoloring is not clarified in detail, but it is understood that a small amount of water contained in the WO ₃ thin film and the insulating film (ion conductive layer) controls coloring / decoloring of WO _3. ing. The coloring reaction equation is estimated as follows.

By the way, at least one of the pair of electrode layers sandwiching the EC layer directly or indirectly must be transparent in order to show the color of the EC layer to the outside. Both must be transparent, especially for transmissive ECDs. Currently, transparent electrode materials include SnO ₂ , In ₂ O ₃ and ITO (SnO ₂ and In ₂ O ₃
However, because of their relatively poor transparency, these materials must be made thin.For this reason and other reasons, ECD is used on substrates such as glass and plastic plates. It is usual to form the structure in FIG. 3, and an example of the structure of such an ECD is shown in FIG.

In FIG. 3, (A) is an upper transparent electrode, (B) is a lower transparent electrode, (E) is a reduction coloring EC layer (eg WO ₃ ),
(D) shows an ionic conductive layer, (C) shows a reversible electrolytic oxidation layer (for example, oxidation or iridium hydroxide), and basically, the ECD is constituted only by the laminated structure of (A) to (B). However, as described above, these ECDs are formed on the element substrate (S). (R) is an ECD sealing resin such as an epoxy resin, and (G) is a protective sealing substrate.

[Problems to be solved by the invention]

Conventionally, as shown in FIG. 3, the sealing resin (R) is between the sealing substrate (G) and the element substrate (S), so that the sealing substrate (G) is the sealing resin (R) and is the element. However, there is a problem that the sealing substrate (G) may peel off if the adhesive strength is not sufficient.

An object of the present invention is to make it difficult to peel off the sealing substrate (G).

[Means for solving problems]

Then, as a result of earnest research, the present inventors have come up with the idea of causing a part of the sealing resin to wrap around to the upper side of the sealing substrate, and have achieved the first aspect of the present invention.

Therefore, the first invention of the present application is that "at least the upper electrode layer, on one surface of the element substrate,
In an electrochromic element obtained by sealing an EC element formed by providing an electrochromic layer and a lower electrode layer with a sealing substrate via a sealing resin, a part of the sealing resin is An electrochromic device characterized in that it is wrapped around to the upper side.

In order to manufacture the ECD of the first invention, the inventors further researched and made two inventions relating to a manufacturing method.

One of them is the second invention of the present application, which is as follows.

"After applying the sealing resin to the electrochromic element formed on the element substrate, placing the sealing substrate, then reversing the whole so that the sealing substrate is on the lower side, After floating and fixing, the sealing resin protruding from between the element substrate and the sealing substrate is infiltrated into the gap between the sealing substrate and the jig plane, and after hardening the sealing resin, it is removed from the jig plane. Manufacturing Method of Sealed Electrochromic Element Characterized by Separation "The rest is the third invention of the present application, which is as follows.

"After applying the sealing resin on the sealing substrate that is slightly floated and fixed on the jig plane, the electrochromic element formed on the element substrate is placed on the sealing resin applied with the element side down. Place the device on the surface of the jig and let the sealing resin protruding from between the element substrate and the sealing substrate enter the gap between the sealing substrate and the jig plane, then cure the sealing resin and then separate it from the jig plane. Manufacturing method of a sealed electrochromic device, characterized in that] [Operation] The laminated structure of the ECD in the present invention is not particularly limited, as the structure of the solid ECD, for example, A four-layer structure such as electrode layer / EC layer / ion conductive layer / electrode layer; a five-layer structure such as electrode layer / reduction coloring type EC layer / ion conductive layer / reversible electrolytic oxidation layer / electrode layer.

As the material of the transparent electrode, for example, SnO ₂ , In ₂ O ₃ , ITO or the like is used. Such an electrode layer is generally formed by a vacuum thin film forming technique such as vacuum deposition, ion plating or sputtering. (Reducing colorability) As the EC layer, WO ₃ , MoO ₃ or the like is generally used.

As the ion conductive layer, for example, silicon oxide, tantalum oxide, titanium oxide, aluminum oxide, niobium oxide, zirconium oxide, hafnium oxide, lanthanum oxide, magnesium fluoride or the like is used. These material thin film is an insulator for electrons by the production method, a proton (H ⁺⁾ and hydroxy ions ^- a good conductor for (OH). Cations are required for the color-erasing reaction of the EC layer, and H ⁺ ions and Li ⁺ ions must be contained in the EC layer and others. The H ⁺ ion need not be Io from the beginning,
H ⁺ ions need only be generated when a voltage is applied, and thus water may be contained in place of the H ⁺ ions. This water is very small and sufficient, and often water that naturally enters from the atmosphere will also fade.

Either of the EC layer and the ion conductive layer may be on the upper side or the lower side. Further, a reversible electrolytic oxidation layer or a catalyst layer may be arranged with an ion conductive layer sandwiched between the EC layer (which also serves as an oxidation coloring EC layer in some cases). Examples of such a layer include iridium oxide or hydroxide, nickel, chromium, vanadium, ruthenium, rhodium and the like. These substances may be dispersed in the ion conductive layer or the transparent electrode, or may be dispersed therein. The opaque electrode layer may also serve as the reflection layer, and for example, a metal such as gold, silver, aluminum, chromium, tin, zinc, nickel, ruthenium, rhodium, stainless steel is used.

[Embodiment 1 ... Embodiments of the first and second inventions] An ITO electrode layer is formed on the entire surface of a rectangular glass element substrate (S), and then an ITO electrode layer is formed by photoetching or laser cutting for the upper electrode (A). A groove was formed between the extraction part (F) and the lower electrode (B). As a result, the extraction portion (F) and the rectangular lower electrode (B) separated from the extraction portion (F) were formed. Alternatively, these patterns may be directly formed by mask-depositing ITO.

Next, a reversible electrolytic oxidation layer (C) made of a mixture of iridium oxide and tin oxide, a tantalum oxide layer (D) and a tungsten oxide layer (E) were formed in order. Finally, Al was vapor-deposited as the upper electrode (A) to produce an ECD. At this time, Al was formed so that one end thereof contacts the take-out portion (F) already formed on the substrate (S).

On the other hand, a jig plane (I) is prepared, on which a thickness of about 0.5 mm
Then, a rectangular spacer (J) smaller than the sealing substrate (G) is placed (see FIG. 4). Spacer (J)
Is for fixing the sealing substrate (G) so that it is slightly above the jig plane (I).

Then, a liquid sealing resin (R) made of an epoxy resin was applied onto the ECD, and a rectangular glass sealing substrate (G) smaller than the element substrate (S) was placed thereon (see FIG. 5). .

Here, the whole was quickly reversed and then placed on the spacer (J). Then, a gap is created between the sealing substrate (G) and the jig plane (I) by the spacer (J), and the sealing resin (R) protruding from the sealing substrate (G) is caused by the capillary phenomenon. (G) enters the gap between the jig plane (I).
This state is shown in FIG.

The encapsulating resin (R) will eventually cure if left at room temperature or under heating, so after confirming the cure, peel it off from the spacer (J) and jig plane (I), and take out the upper and lower electrodes. The ECD of the present embodiment is completed by bonding the external wirings L _A and L _B to the respective parts. This is the ECD shown in FIG.

The jig plane (I) and the spacer (J) are preferably made of Teflon or silicon rubber because the sealing resin (R) does not adhere after curing.

When a coloring voltage (+ 1.35V) is applied from the drive power supply (Su) to this ECD, the reflectance is reduced to 15% for the light (L) with a wavelength of 633 nm incident from the substrate (S) side (after 10 seconds). ), This reflectance was maintained for a while even when the voltage application was stopped. This time, when the decoloring voltage (-1.35V) is applied, the reflectance is 65%.
% Recovered (after 10 seconds).

This ECD is useful as an anti-glare mirror that can electrically control the amount of reflected light.

[Embodiment 2 ... Embodiments of the first and third inventions] An ITO electrode layer is formed on the entire surface of a rectangular glass element substrate (S), and then an ITO electrode layer is formed by photoetching or laser cutting for the upper electrode (A). A groove was formed between the extraction part (F) and the lower electrode (B). As a result, the extraction portion (F) and the rectangular lower electrode (B) separated from the extraction portion (F) were formed. Alternatively, these patterns may be directly formed by mask-depositing ITO.

Next, a reversible electrolytic oxidation layer (C) made of a mixture of iridium oxide and tin oxide, a tantalum oxide layer (D) and a tungsten oxide layer (E) were formed in order. Finally, Al was vapor-deposited as the upper electrode (A) to produce an ECD. At this time, Al was formed so that one end thereof contacts the take-out portion (F) already formed on the substrate (S).

Here, prepare two conductive clips (H) made of phosphor bronze with a U-shaped cross section, and connect external wiring (L _A ) or (L _B ) to each by soldering or conductive adhesive. did.

Two of these clips (H) were attached to the short sides of the element substrate (S), so that the clips (H) crimped the lead-out portions of the upper and lower electrodes (see FIG. 9).

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 ECD could be masked.

On the other hand, as shown in FIG. 7, the thickness is about 0.
A sealing jig (K) integrally formed with a 5 mm rectangular spacer (J smaller than the sealing substrate (G)) was prepared.

A rectangular glass sealing substrate (G) larger than the spacer and smaller than the element substrate (S) is placed on the spacer (J) of the sealing jig (K), and the sealing substrate (G) is placed on the sealing substrate (G). The sealing resin (R) was applied. This state is shown in FIG. Otherwise, the sealing substrate (G) may be coated with the sealing resin in advance and then placed on the spacer (J).

The spacer (J) makes a gap of about 0.5 mm between the sealing substrate (G) and the jig plane (I). Then, the ECD of FIG. 9 formed earlier is reversed (that is, the element substrate (S) is on the upper side and the ECD is on the lower side) and placed on the sealing resin (R) of FIG. . Then, the sealing resin (R) protruding from the sealing substrate (G) enters into the gap between the sealing substrate (G) and the jig plane (I) due to the capillary phenomenon, and the resin (R)
It hardened soon. Then, peel it off from the sealing jig (K),
The ECD of this example was obtained.

The sealing jig (K) made of Teflon or silicon rubber is convenient because the sealing resin (R) does not adhere after curing.

When a coloring voltage (+ 1.35V) is applied to this ECD from the startup power supply (Su), the reflectance for light (L) with a wavelength of 633 nm incident from the substrate (S) side is reduced to 15% (after 10 seconds). ), This reflectance was maintained for a while even when the voltage application was stopped. This time the reflectance is 65% when an erasing voltage (-1.35V) is applied.
Recovered (after 10 seconds).

This ECD is also useful as an antiglare mirror.

〔The invention's effect〕

As described above, according to the first aspect of the present invention, the sealing substrate (G) and
Since a part of the sealing resin between the ECD and the ECD is wrapped around the upper side of the sealing substrate (G), the sealing substrate (G) is adhered only by the adhesive force of the sealing resin (R). Since it is not limited to being held by the sealing resin (R), the risk of the sealing substrate (G) peeling is eliminated.

Further, according to the second and third inventions, the excess sealing resin (R) protruding from the sealing substrate (G) is made to wrap around to the upper side of the sealing substrate (G) (which corresponds to the back side in use). Therefore, it is unnecessary to wipe off the protruding sealing resin (R), the protruding sealing resin does not contaminate the end surface portion and the front side of the element substrate (S), and the sealing resin (R) is used as an electrode. Since it is difficult to cover the extraction part, the work is easy when the external wiring is bonded later.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of an ECD according to a first embodiment of the present invention. FIG. 2 is a schematic vertical sectional view of an ECD according to the second embodiment of the present invention. FIG. 3 is a schematic vertical sectional view of a conventional ECD. FIG. 4 is a schematic vertical cross-sectional view of a jig for providing a jig plane (I) used in Example 1 and a spacer (J) placed thereon. FIG. 5 shows the EC formed on the element substrate (S) in Example 1.
FIG. 6 is a schematic vertical cross-sectional view showing a state immediately after the sealing resin (R) is applied on D and the sealing substrate (G) is placed thereon. FIG. 6 is a schematic vertical cross-sectional view showing a state after the one shown in FIG. 5 is reversed and placed on the one shown in FIG. 4 and after a while. FIG. 7 is a schematic vertical sectional view of a sealing jig (K) with a spacer (J) used in Example 2. FIG. 8 is a schematic vertical cross-sectional view showing a state in which the sealing substrate (G) is placed on the sealing jig (K) and the sealing resin is applied thereon in Example 2. FIG. 9 is a schematic vertical sectional view of an ECD in the process of being manufactured according to Example 2. [Explanation of symbols of main parts] A: Upper electrode (ECD in a narrow sense) B: Lower electrode (ECD in a narrow sense) E: WO ₃ layer or reduction coloring EC layer (ECD in a narrow sense) ) D ... Ion conductive layer (ECD in a narrow sense) C ... Reversible electrolytic oxidation layer (ECD in a narrow sense) ECD ... Electrochromic element S ... Element substrate G ... Encapsulation substrate R ... Encapsulation Stop resin H …… Clip I …… Jig plane J …… Spacer K …… Sealing jig (I and J are joined together)

Claims (3)

[Claims] 1. An EC element formed by providing at least an upper electrode layer, an electrochromic layer and a lower electrode layer on one surface of an element substrate and sealing the EC element with a sealing resin via a sealing resin. In the electrochromic device, the electrochromic device is characterized in that a part of the encapsulating resin is wrapped around the upper side of the encapsulating substrate. 2. An electrochromic element formed on an element substrate is coated with a sealing resin, and then the sealing substrate is placed,
Next, the whole is reversed so that the encapsulation substrate is on the lower side, and the encapsulation resin protruding from between the element substrate and the encapsulation substrate is fixed by slightly floating it on the jig plane. A method for manufacturing a sealed electrochromic device, which comprises intruding into a gap with a flat surface, then curing the sealing resin, and then separating from the jig flat surface. 3. An encapsulation resin is applied onto an encapsulation substrate which is slightly floating and fixed on a jig plane, and then an electrochromic element formed on an element substrate is applied with the element side down. Placed on the sealing resin, the sealing resin protruding from between the element substrate and the sealing substrate is caused to enter the gap between the sealing substrate and the jig plane, and after the sealing resin is cured,
A method for manufacturing a sealed electrochromic device, characterized by separating from a jig plane.