JPH01167736A - Electrochromic element - Google Patents

Abstract

PURPOSE:To obviate stagnation of gases and to prevent deterioration with lapse of time by forming vacant grooves arriving at sealing materials between a reaction layer and nonporous substrate and providing the sealing materials with air permeability. CONSTITUTION:The side peripheral faces of a light control body 1 are closed by the sealing materials 6, 6 consisting of a porous material and between both substrates 2 and 2 is sealed. Since the sealing material 6 consists of the porous material, the material has air permeability. On the other hand, the vacant grooves 7-7 are formed between the transparent substrate 2' and the reaction layer 5. The grooves 7 arrive at the sealing material 6 along the surface of an electrode layer 3'. The transparent substrate 2 is provided with grid-like ruggedness by hollow grooves 2'a, 2'b which run vertically and horizontally on the electrode forming surface. The electrode layer 3' is formed on the substrate along the ruggedness. Then, the spaces remain finally in the hollow grooves 2'a, 2'b and are, therefore, retained as the vacant grooves 7. The stagnation of the gases generated by the electrode is thereby effectively prevent and the inter-layer exfoliation is obviated.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to an electrochromic device [Background Art] A light control glass (light control body) using an electrochromic device changes the amount of light transmitted according to the amount of incident light. can be controlled arbitrarily, and is expected to be used as a window material for buildings, automobile window glass, and a dimming material for lighting equipment.

This light control glass includes an electrochromic element between two pairs of transparent glass substrates. As an electrochromic element, an electrochromic material layer and an ion conductive layer are provided between a pair of electrode layers formed on each glass substrate. This element performs light control by applying a voltage between the picture electrode layers and adjusting the degree of coloring of the electrochromic material layer. The coloring and decoloring of the electrochromic material layer is an electrochemical reaction.

Conventionally, a liquid electrolyte has been used as the ion-conducting layer, but the element is easily destroyed due to leakage or expansion of the electrolyte and is not durable. Therefore, attempts have been made to use solid ion conductive layers such as organic solid electrolytes, inorganic solid electrolytes, or solid dielectrics.

However, in an electrochromic device using a solid ion-conducting layer, oxygen gas and hydrogen gas are generated at the electrodes during operation, but because of the glass substrate, these gases cannot escape and remain there. The stagnant gas becomes bubbles, leading to deterioration in translucency and appearance, and peeling between layers, leading to deterioration of response speed and degree of coloring over time. It is also possible to use a porous glass substrate and form electrodes on it to allow gas to escape through the pores of the substrate.
Since the porous glass substrate has a high diffuse reflectance, there is a problem in that the transmitted light is significantly reduced.

[Purpose of the invention]

In view of the above circumstances, it is an object of the present invention to provide an electrochromic element that can effectively prevent gas generated in an electrode layer from stagnation without reducing transmitted light.

[Disclosure of the invention]

In order to achieve the above object, the present invention provides a reaction layer consisting of an electrochromic material layer and a solid ion conductive layer between a pair of electrode layers, and a non-porous substrate superimposed on the outer surface of at least one electrode layer. In the electrochromic device, in which the side peripheral surfaces of the reaction layer and the electrode layer are closed with a sealing material, a groove reaching the sealing material is formed between the reaction layer and the non-porous substrate. At the same time,
The gist of the present invention is an electrochromic device characterized in that the sealing material has air permeability.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of an electrochromic device (hereinafter referred to as an "rEL device") according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a light control body equipped with an EL element according to an embodiment of the present invention.

The light control body 1 has a non-porous transparent substrate 2.2' overlaid on each outer surface of a pair of transparent electrode layers 3.3', and a bipolar electrode layer 3.
．． A reaction layer consisting of an electrochromic material layer 4 and a solid ion-conducting layer 5 is provided between the inner surfaces of 3'. The side peripheral surface of the light control body 1 is covered with a sealing material 6.6 made of a porous material, and the space between the two transparent substrates 2.2' is sealed.

Since the sealing material 6 is made of a porous material, it is breathable. On the other hand, there are grooves 7...7 between the transparent substrate 2' and the reaction layer.
is formed. This groove 7 reaches as far as the sealing material 6 along the surface of the electrode layer 3'.

The sealing material 6 and the grooves 7 effectively prevent the gas generated at the electrodes from stagnation without reducing transmitted light.

The gas generated in the electric cooperative passes through the air groove 7 and enters the side sealing material 6.
, and exits from the EL element 1 through the pores of the sealing material 6. Since there is no gas stagnation, the appearance of bubbles and separation between layers will not occur. Furthermore, since the transparent substrate 2' is made of a non-porous material rather than a conventional porous material, there is no need to reduce transmitted light. The hollow groove 7 is formed on the transparent substrate 2'
It may be provided on the transparent substrate 2 side instead of on the side, or it may be provided on both sides of the transparent substrate 2.2'.

Note that the air groove 7 of the EL element 1 is formed in the following manner. As shown in FIG. 2, the transparent substrate 2' has a lattice-like unevenness formed by grooves 2'a and 2'b running vertically and horizontally on the electrode forming surface. And electrode layer 3'
are formed along these unevenness. In this case, a space will ultimately remain in the grooves 2'a and 2'b, which will be used as the air conditioner 7.

The grooves 2'a and 2'b can be formed by press molding, etching, laser processing, etc.

Although the groove 2'as2'b is not particularly limited, it usually has a width of 50 to 500 μm1. Depth 10-100
μm, and the distance between adjacent grooves is selected from the range of 100 μm to l + u. The cross-sectional shape of the groove may be wedge-shaped, rectangular, semicircular, or the like. The uneven pattern is not limited to a grid pattern, but may be a stripe pattern with grooves in only one direction, a diagonal stripe pattern, or the like.

The sealing material 6 is preferably a porous material having about 50 to 2000 pores, but is not limited to this, and any material that is breathable may be used. Specifically, there are porous glass and porous resin. Furthermore, the entire sealing material 6 does not need to have air permeability;
Air permeability may be provided only around the sides of the electrode layer 3' where the air grooves 7 reach. However, making the sealing material 6 partially breathable takes time and effort in manufacturing.

The transparent substrate 2.2' is made of non-porous glass, non-porous plastic (including film), etc.
A transparent electrode such as tin oxide, indium oxide, or indium tin oxide (ITO) is used for the electrode layer 3.3'. Note that the EL element does not need to have transparent substrates on both sides. There may be a transparent substrate on only one side, and the electrode layer may be exposed on the other side.

The electrochromic material layer 4 includes tungsten dioxide (WO, ), tungsten trioxide (WO, ),
Scraps such as molybdenum dioxide (MoOz), molybdenum trioxide (Moon), Prussian blue (PB), vanadium pentoxide, chromium oxide, iridium hydroxide, and nilagel hydroxide are used. This electrochromic material layer 4 can be formed using a vacuum evaporation method, a sputtering method, or a sol-based method.
It is formed on the electrode layer 3 by a gel method or the like.

As the solid ion conductor N5, one made of a solid polymer electrolyte, a dielectric material, etc. is used. Examples of solid polymer electrolytes include those in which salts such as potassium chloride and lithium perchlorate are dissolved in polymer materials such as polymethyl methacrylate and polyethylene oxide. The amount of salt added is preferably in the range of 1 to 20 parts by weight per 100 parts by weight of the polymer component. If it is less than 1 part by weight, it becomes difficult to obtain an effect as an electrolyte, and if it exceeds 20 parts by weight, salt precipitation occurs and the appearance deteriorates. For the dielectric material, Adz
Os, Siog, Ta205, Zr0z, L
There are iF, MgFz, etc., and it is formed by a vacuum evaporation method, a sputtering method, a sol-gel method, etc.

Next, more specific examples and comparative examples will be described.

(Example 1) A non-porous glass plate was used as the transparent substrate 2, and I
TO was vapor-deposited to form an electrode layer 3, and WO,5 was vacuum-deposited as an electrochromic substance N4 on this electrode layer 3. Then, a solid polymer electrolyte layer was formed as a solid ion conductive layer 5 on this WO layer in the following manner. Polyethylene oxide (molecular weight txlo')
0.1 g of LiCj204 is added to a 1% aqueous solution at 100 mA, stirred, and left to stand for 24 hours, then coated on the WO1 layer to form a solid electrolyte layer. On the other hand, the transparent substrate 2' is made of non-porous glass, with a width of 100 μm, a depth of 100 μm, and an interval of 500 μm.
After forming micrometer grooves in a lattice shape, ITO is deposited to form an electrode layer 3'. Thereafter, the electrode layer 3' was crimped onto the solid electrolyte layer, and a sealing material 6 made of porous glass with an average pore size of 1000 was adhered to the side circumferential surface with epoxy resin to complete the light control body 1. .

(Example 2) Except that a Prussian blue layer was formed as the electrochromic material layer 4 by electrolytic oxidation-reduction method,
A light control body 1 was obtained in the same manner as in Example 1.

(Example 3) A non-porous glass plate was used as the transparent substrate 2, and the width was 100μ.
After forming grooves with a depth of 100 μm and an interval of 500 μm in a lattice shape, ITO is deposited to form an electrode layer 3, and on this electrode layer 3, an electrochromic material layer 4 of WO2 is formed.
The layers were vacuum deposited.

Then, TazOsFi was formed as a solid ion conductive layer 5 on this WO3 layer. Then, ITo is deposited to form an electrode layer 3', and then the average pore size is 1 on the side circumferential surface.
The light control body 1 was completed by bonding a sealing material 6 made of 0.000 mm porous glass with an epoxy resin.

[Comparative example]

The IN light body 1 was fabricated in the same manner as in Example 1, except that no grooves were formed on the transparent substrate 2' and the side peripheral surface was sealed only with epoxy resin without using the sealing material 6. completed.

The characteristics of Examples 1 to 3 and Comparative Example were investigated. Regarding deterioration over time, we looked at changes in the degree of coloration over time. In addition, the appearance of air bubbles and peeling between the eyebrows were observed using an optical microscope.

Changes in the degree of coloring over time were measured by applying voltage alternately to the electrodes and
After repeating coloring and decoloring 10 times, the absorbance of a specific wavelength in the colored state immediately after the start of coloring and decoloring and immediately before the end of the repetition is measured, and the absorbance ratio is calculated as [absorbance immediately before the end of repetition] ÷ [decolorization] Judgment was made from the initial absorbance immediately after the start]. The larger the absorbance ratio, the better the aging characteristics. The results are shown in Table 1.

Table 1 As shown in Table 1, Examples 1 to 3 showed significantly less change in the degree of coloring over time than the comparative example, and even when observed with an optical microscope, Examples 1 to 3 showed no air bubbles or gaps between each layer. No peeling was observed, whereas in the comparative example, the appearance of air bubbles and peeling between the eyebrows were observed.

This invention is not limited to the above embodiments. For example, the E7 element may be used as an EL display element in addition to a light control device.

〔Effect of the invention〕

As described above, the EL element of the present invention has little deterioration over time because there is no gas retention, and furthermore, since the substrate is non-porous, there is no reduction in transmitted light.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a light control body which is an example of an EL element according to the present invention, and FIG. 2 is a perspective view of the transparent substrate on which grooves are formed in the light control body. be. 1... Light control body 2.2'... Transparent substrate 3.3
′...Electrode layer 4...Electrochromic material layer 5...Solid ion conductive layer 6...Sealing material 7...
Karazo 2'as 2"b...Kagamizo Agent Patent Attorney Takehiko Matsumoto Figure 1 Figure 2 Procedural Amendment (Daily 1.1 Timing of the Cattle 1986 Tokuhijo 32'5911 No. 2 , Name of the invention Electrochromic device 3, Prefectural affiliation with person making the correction, Hanyu Patent applicant address 1048 Oaza Kadoma, Kadoma City, Osaka Name (583) Representative of Matsushita Electric Works Co., Ltd. (UW role Toshio Miyoshi 4, No agent 6, Specification subject to amendment 7, Contents of amendment■ Page 4, line 15 of the specification, page 4, line 18, page 5, line 15, page 6, line 3, page 7 Line 13, Page 13, No. 6
~ line 7, page 13, line 7, page 13, line 10 and 1
rELJ is written in 9 places on page 3, line 15, rECJ.
I am corrected. - In the 17th line of page 5 of the specification, "transparent substrate 2'" is corrected to "transparent substrate 2.2'." (2) Delete "tungsten dioxide (W Ox)" from lines 16 to 17 on page 7 of the specification. ■ On page 7, line 18 of the specification, “Molybdenum dioxide (Mo
b, )," is deleted.

Claims (2)

[Claims] (1) A reaction layer consisting of an electrochromic material layer and a solid ion conductive layer is provided between a pair of electrode layers, a non-porous substrate is superimposed on the outer surface of at least one electrode layer, and the reaction layer and the electrode In an electrochromic device in which a side peripheral surface of a layer is closed with a sealing material, a groove reaching the sealing material is formed between the reaction layer and the non-porous substrate, and the sealing material An electrochromic element characterized by having air permeability. (2) Since the sealing material is made of a porous material, it has air permeability, and the surface of the non-porous substrate is uneven with grooves running vertically and horizontally. 2. The electrochromic device according to claim 1, wherein an electrode layer is formed on the groove, and the space left in the groove is an empty groove.