JPS63106730A - Dimmer body - Google Patents

Abstract

PURPOSE:To improve response speed, and to prevent a dimmer from generation of foams and deterioration of response speed when the dimmer is driven under direct irradiation of sun light by using an electrolyte contg. at least a quinone compd. and/or a ferrocene compd. and an I ion source material as redox agents dissolved in an org. solvent having S=O group. CONSTITUTION:An I compd. having high reaction velocity and high durability serving as an I ion source material, is used together with a quinone compd. and/or a ferrocene compd. as redox agent of an electrolyte for a dimmer material. Suitable solvent for dissolving said redox agents is an org. solvent having S=O group having high stability against direct irradiation of sun light and heat providing high durability. When the I ion source material has no function as cation source, other cation source is adopted. Particularly, the electrolyte is used in the form of gel together with an added polymer serving as a gelling agent to the electrolyte. By this constitution, stable preparation of a dimmer material is possible and a dimmer material which is stable thermally against direct irradiation of sun light causing no foam generation nor coloring by the effect of light is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a light control body using an electrochromic (EC) substance.

[Prior Art] In recent years, light control bodies using EC substances have begun to be used as anti-glare mirrors, light control windows, and the like.

A light control body using such an EC material is usually constructed by interposing an EC material such as tungsten oxide or molybdenum oxide and an electrolyte containing ions capable of coloring the EC material between electrode substrates.

As the above-mentioned electrolyte, various compositions are being considered as systems containing protons or lithium ions and having good conductivity. A typical solution-type electrolyte is one in which a lithium ion source material such as lithium perchlorate is dissolved in a solvent such as propylene carbonate, as described in JP-A-55-138720. Are known. On the other hand, lithium conductive solid electrolytes using lithium nitride or lithium iodide are also known.

[Problems to be Solved by the Invention] The present inventors discovered in Japanese Patent Laid-Open No. 58-30729 that a light control body using a transparent electrode as a counter electrode can be obtained by adding a redox agent to an electrolyte. It shows. Among the redox agents used in this electrolyte, it was found that an iodine ion source material that ionizes iodine ions exhibits superior characteristics in terms of responsiveness and durability compared to other redox agents.

However, when lithium iodide is used as an iodine ion source material in the form of a solution, if propylene carbonate is used as a solvent, carbon dioxide gas is generated at high temperatures, and lithium carbonate is further precipitated. The drawback was that carbon dioxide gas was also generated when irradiated.

Furthermore, when an alcoholic solvent such as butyl alcohol is used, when irradiated with light, a photochromic phenomenon occurs, that is, the flat band potential of the surface of the EC substance 1, for example, tungsten oxide, in contact with the electrolyte solution shifts in the positive direction. It has the drawbacks of being easily colored by light and generating hydrogen gas.

Furthermore, in order to improve this, the present inventors also proposed
In No. 1-32038, a light control body using an electrolyte prepared by mixing lithium iodide and a gelling polymer with a lactone solvent has also been proposed.

However, even when this lactone-based solvent is used, the range of manufacturing conditions to obtain good performance is narrow, and the EC
There was a drawback that the electrolyte decomposed due to the photochromic phenomenon of the substance and the reduction of the counter electrode, resulting in a considerable amount of foaming.

For this reason, there has been a desire for an electrolyte light control body that can be manufactured stably under a wide range of manufacturing conditions, is thermally stable even under direct sunlight, and does not cause phenomena such as foaming and coloring due to light.

[Means for Solving the Problems] The present invention has been made to eliminate the above-mentioned drawbacks of conventional light control bodies, and includes an electrochromic material layer and an electrolyte interposed between opposing electrode substrates. In the light control body, the electrolyte is an organic solvent containing at least S=O (excluding sulfonic acid type), at least one of a quinone compound or a ferrocene compound as a redox agent, and an iodine ion source. The present invention provides a light control body characterized by containing an iodine compound and a cation source substance when the iodine ion source substance does not function as a cation source.

That is, the light control body of the present invention uses an iodine compound as an iodine ion source material with excellent reaction speed and durability as an electrolyte redox agent, and also uses at least one of a quinone compound or a ferrocene compound. As the solvent for dissolving the redox agent, an organic solvent having S-〇, which is a solvent that is stable and highly durable against direct sunlight and heat, is used, and the iodine ion source material acts as a cation source. If not, a cation source substance is used, and in particular, a polymer is added to the electrolyte as a gelling agent to gel the electrolyte.

The present invention will be explained in detail below.

The electrode substrate is an electrode formed by forming a transparent conductive film such as tin oxide, indium oxide, or tin oxide-indium oxide (ITO) on the surface of a substrate such as glass or plastic by a known method such as coating, vapor deposition, or sputtering. etc. are used. Further, if necessary, fine wire leads made of metal such as aluminum, chromium, titanium, or conductive paste may be laminated on this transparent conductive film in the form of a line, a grid, or the like.

Note that if the light does not need to pass through the light control body, such as from a light control mirror, one of the substrates may not be transparent, and may be made of ceramic or a metal such as aluminum or titanium, or may be made of an electrode. Reflective electrodes such as titanium nitride, zirconium nitride, and nophnium nitride may be used as the electrode.Furthermore, when used as a light control mirror, both electrode substrates should be transparent, and one electrode - A mirror surface may be formed on the back surface of the polar substrate.

As the EC material, known EC materials such as tungsten oxide, molybdenum oxide, titanium oxide, and iridium oxide are used, but tungsten oxide or a tungsten oxide-based material containing tungsten oxide as a main component is preferable.

As the organic solvent of the present invention, S=O other than sulfonic acid type
Organic solvents containing groups can be used, including sulfonamides, sulfoxides, and the like. Organic solvents containing this S=O group are stable even under direct sunlight, and improve the weather resistance of the light control body.In the present invention, these organic solvents are used alone or in combination, These are usually used alone, but other organic solvents may be mixed within a range of 50 wt % or less as long as the weather resistance of the electrolyte and the effects of other components are not deteriorated.

In the present invention, two types of substances are used in combination as redox agents for electrolytes.

One of these is an iodine compound that serves as an iodine ion source. Specifically, metal iodides such as lithium iodide and sodium iodide, and ammonium-based iodides such as ammonium iodide and tetraethylammonium iodide are used. It will be done. The iodine compound that serves as the iodine ion source is EC
When a substance is colored or erased, it has excellent reaction speed and durability, and there is no need to form a special EC substance, carbon, or other electrode on the counter electrode. The amount of the iodine compound to be added to the solvent may range from 0.001 M1 to a saturation amount, and is usually about 0.1 to 1 m/ml.

Note that when using ammonium-based iodides, etc., or when using metal iodides that form cations that do not color or fade the EC material, use a cation source material containing cations such as protons and lithium ions that color the EC material layer. Added for ion implantation into the material layer. The cation source substances include lithium perchlorate, sodium perchlorate,
Examples include lithium boron tetrafluoride and sodium boron tetrafluoride. The amount of the cation source substance to be added to the solvent may range from 0.001 M/liter to a saturation amount, and usually about 0.1 to 1 M/i.

As the second redox agent, at least one of a quinone compound or a ferrocene compound is added. IT
When iodine ions perform the l/I+- redox reaction on the O electrode, etc.! Compared to the oxidation reaction from - to I3-, I
``Because the reduction reaction of Karato is extremely biased towards the negative side,
Strong adsorption of I3- to the electrode can ensure high memory performance, but on the other hand, there is a risk of reduction of the electrode and decomposition of the solvent. In addition, I3- is easily decomposed by ultraviolet rays, generating gas and easily leading to foaming.

The second redox agent serves to compensate for these deficiencies. For this, its redox potential must be between 0 and 1.25.
A redox agent that is within the range of
Quinone-based compounds or ferrocene-based compounds can be used. In the case of quinone compounds, they are used in their oxidized form. Specifically, among quinone-based compounds, benzoquinone or substituted benzoquinones such as xyquinone, chloranil, chloranilic acid, etc., or ferrocene-based compounds such as ferrocene or substituted ferrocene are preferred.

This second redox agent is 0.001-0. IM/4
It is sufficient if it is added to a certain extent.

The addition of this second redox agent has the effect that this second redox agent is more easily reduced than an electrode such as ITo, and that this addition can suppress the decomposition of I3- under ultraviolet irradiation. , electrode reduction, gas generation, etc. can be prevented.

In particular, by adding the above two types of redox agents to an organic solvent containing S=O, the response characteristics are good,
A light control body that has a long life and is resistant to deterioration even under direct sunlight can be easily obtained.

For electrolytes containing such redox agents, the counter electrode must be a transparent or reflective electrode, and opaque counter electrodes cannot be formed like normal display elements, such as dimmable mirrors and dimming windows. Particularly effective results can be obtained when used in dimmers such as Further, the light control body of the present invention has a cycle life of 106 times or more for color development/decolorization when used as a small-sized transmission type display, and can be used as a display sufficiently for practical use by devising a driving method.

In the present invention, it is further preferable to add a gelling agent to the electrolyte from 1 wt % to a saturation amount to increase the viscosity of the electrolyte solution and gel it. From the viewpoint of the manufacturing process and prevention of electrode short circuits, it is preferable that the polymer used as the gelling agent is adjusted to have a viscosity of about 10 3 to 10 5 cps when dissolved in an organic solvent.

The gelling agent is desirably one that has good weather resistance, particularly against direct sunlight, is stably soluble in the above-mentioned solvent, is electrochemically stable, and has adhesive properties to the electrode substrate. Specifically, polyethylene oxide-based, polyacrylonitrile-based, polymethyl methacrylate-based, or polyvinylpyrrolidone-based polymers are preferred.

The dimmer has a relatively large surface area and is often used standing up, and due to hydrostatic pressure, the electrolyte solution often falls downward, causing the lower part of the dimmer to swell, and pressure from the outside If this happens, the two electrode substrates may come into contact and cause a short circuit. However, such accidents can be prevented by adding a polymer to the electrolyte to form a gel electrolyte. Furthermore, even if the electrode substrate is damaged for some reason, the electrolyte and the electrode substrate are unlikely to scatter and are safe. Furthermore, since the electrolyte is less likely to leak, the strength of the seal does not need to be low, and the area of the seal portion can be reduced, which has the advantage of reducing stress on the substrate and optical distortion.

[Example] The present invention will be explained in detail below.

Example 1 A transparent electrode was formed by coating an ITo film to a thickness of 1500 mm on a 10 cm square glass front substrate by vapor deposition. Further, a W2B film having a thickness of 5000 was deposited on the transparent electrode on the back substrate to form an EC material layer.

Further, an ITo film was vapor-deposited to a thickness of 1500 mm on a 10 c+a square glass front substrate to form a transparent electrode.

As an electrolyte, 0.7 as a redox agent to sulfolane
Using a gel-like material in which 5M1 lithium iodide, 0.01M1 p-xyquinone, and 5wt% polyethylene oxide are dissolved, the EC material layer of the back substrate and the front surface are formed so that the thickness of the electrolyte layer is about 50 gm. A light control body was manufactured by inserting it between the transparent electrode of the substrate and fixing it by pressure.

The response speed of the light control body made in this way from 80% to 20% coloring at O'C is about 10 seconds, which is equivalent to that when using a conventional γ-butyrolactone electrolyte, and Even when driving for coloring and decoloring under direct sunlight, no deterioration in appearance such as bubbling or abnormality in response characteristics occurred even after driving 105 times or more.

In the case of a conventional light control body using a γ-butyrolactone electrolyte, there is no appearance deterioration such as foaming even when driving for more than 105 times, even when driving for coloring and decoloring under direct sunlight. However, there were individual differences depending on driving conditions and cell forming conditions, and there were problems in stably manufacturing products that did not deteriorate. However, in the light control body of Example 1, this individual difference was small, and it was possible to easily manufacture a light control body with high weather resistance.

In addition, in the light control body of Example 1, compared to the light control body using a γ-butyrolactone-based electrolyte, the rate of decrease of minute-
, and the degree of coloring due to photochromic phenomenon is 40-50% of the transmittance of γ-butyrolactone type.
In Example 1, the influence was reduced to 60% or more.

In addition, in the standing test in a weather-0 meter, Example 1
Both the light control body and the light control body using a γ-butyrolactone electrolyte showed almost no deterioration even after about 2000 hours. However, in the coloring/decoloring driving test in a weather meter, the difference was noticeable. That is, in a light control body using a γ-butyrolactone electrolyte, the
The light control body of Example 1 foamed in about 50 hrs.
No foaming occurred even after 0 hours.

Since the light control body of this example has gelled electrolyte,
Even when placed vertically, no deformation such as bulges occurred, and even when the glass substrate was intentionally damaged by a stone, not only the gel electrolyte itself but also the glass substrate did not scatter.

Example 2 A light control body was produced in the same manner as in Example 1 except that the organic solvent was replaced with tetraethylsulfonamide.

The response speed of this dimmer is the same as in Example 1, and even when it is driven for coloring and decoloring more than 105 times under direct sunlight, it does not cause any deterioration in appearance such as foaming or abnormalities in response characteristics.
The same characteristics as in Example 1 were also exhibited in the coloring/decoloring drive test in a weather-0 meter. In addition, even when placed vertically, no deformation such as bulging occurs, and even if the glass substrate is intentionally damaged by a stone, not only the gel electrolyte itself but also the gel electrolyte itself will not deform.
There was no scattering of the glass substrate.

Example 3 Example 1 except that the organic solvent was replaced with dimethyl sulfoxide
A light control body was manufactured in the same manner. This light control body is also Example 1
showed similar characteristics.

Examples 4 to 7 Sulfolane was used as the organic solvent and O, ? as the redox agent. 5Mi of lithium iodide and 0.0IMi
benzoquinone (Example 4), chloranil (Example 5)
, chloranilic acid (Example 6), ferrocene (Example 7)
A light control body was manufactured in the same manner as in Example 1 using a gel-like substance in which 5 wt % of polyethylene oxide was dissolved. This light control body also exhibited characteristics similar to those of Example 1.

Example 8 Sulfolane was used as an organic solvent, and 0.75M/4 ammonium iodide and 0.0
A light control body was manufactured in the same manner as in Example 1 using 1M1 chloranil, lithium perchlorate as a lithium ion source, and a gel-like material in which 5 wt % polyethylene oxide was dissolved. This light control body also exhibited characteristics similar to those of Example 1.

Examples 9 to 11 Using sulfolane as an organic solvent, o, 75MAQ of lithium iodide and 0.01M as a redox agent
/41 p-xyquinone, 5 wt% polyacrylonitrile (Example 9), polymethyl methacrylate (Example 10), polyvinylpyrrolidone (Example 11)
) was used to produce a light control body in the same manner as in Example 1. The direct light control body also showed the same characteristics as in Example 1.

Example 12 A light control body was manufactured in the same manner as in Example 1 except that no polymer was added.

The response and life characteristics of this light control body were similar to those of Example 1, but because it was not gelled, the electrodes on both substrates were sometimes short-circuited when pressure was applied perpendicularly to the substrates. Further, when the glass substrate was broken, glass and electrolyte were scattered.

Further, as in this example, when the size is about 10 cm square, the bulge is not very noticeable even if it is arranged vertically, but when it is about 30 cm square, the bottom side bulges considerably.

[Effect of the invention] As explained above, in the light control body of the present invention,
Since an electrolyte in which at least one of a quinone compound or ferrocene compound as a redox agent and an iodine ion source material is dissolved in an S=O type organic solvent is used, the response speed is fast and it can be driven by direct sunlight. It also has less deterioration such as foaming and reduced response speed, and is less susceptible to the effects of other constituent materials such as electrodes and EC substances, as well as to driving conditions.
Products that are stable and have good characteristics can be manufactured easily.

Further, by adding a polymer to this electrolyte and causing it to gel, even when used as a large-area light control body, a spacer is not required and problems such as deformation of the electrode substrate and short circuits are less likely to occur.

In addition, even if the board is damaged, the electrolyte and board are less likely to scatter, and since the electrolyte itself is less likely to flow, a strong seal is not required, making it easier to manufacture the light control body. Since the stress of the seal against the substrate is reduced, optical distortion is less likely to occur.

In particular, in the present invention, by using a polyethylene oxide-based, polyacrylonitrile-based, polymethyl methacrylate-based, or polyvinylpyrrolidone-based polymer,
The heat resistance has also been improved, and the conventional polyvinyl butyral type is 90%
Whereas it could only be used stably up to about ℃,
It can be used up to about 120°C.

This makes it possible to use it in applications where it is exposed to strong light and high temperatures under direct sunlight, and it also becomes possible to use it by installing a light control body on the roof of a house or car.

In addition to this, the present invention can be applied in various ways without detracting from the effects of the present invention, such as large displays that combine windows, ceiling partitions, and light control bodies for various buildings, vehicles, ships, etc. It can be used for equipment, etc.

Claims (8)

[Claims] (1) In a light control body comprising an electrochromic material layer and an electrolyte interposed between opposing electrode substrates, the electrolyte contains an organic solvent containing at least S=O (excluding sulfonic acid type) and a redox agent. A preparation comprising at least one quinone compound or ferrocene compound, an iodine compound serving as an iodine ion source, and a cation source substance when the iodine ion source substance does not function as a cation source. Light body. (2) The light control body according to claim 1, wherein the electrolyte contains a polymer that increases the viscosity of the electrolyte solution and gels the electrolyte solution. (3) The light control body according to claim 1, wherein the organic solvent containing S=O is a solvent containing a sulfoxide group. (4) The light control body according to claim 1, wherein the organic solvent containing S=O is a solvent containing a sulfone group. (5) The light control body according to claim 1, wherein the iodine ion source substance is lithium iodide and functions as a cation source. (5) The light control body according to claim 2, wherein the polymer is a polyethylene oxide polymer. (6) The light control body according to claim 2, wherein the polymer is a polymethyl methacrylate polymer. (7) The light control body according to claim 2, wherein the polymer is a polyacrylonitrile polymer. (8) The light control body according to claim 2, wherein the polymer is a polyvinylpyrrolidone polymer.