JPH0160807B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a light control element and a light control transparent body using a substance exhibiting an electrochromic (hereinafter abbreviated as EC) phenomenon. A light control element that utilizes the EC phenomenon can automatically or artificially control the amount of incident outside light according to the amount of sunlight, and is used in window materials for buildings, automobiles, aircraft window glass, etc. It is expected to be used as a light control element. Conventionally, EC elements have WO ₃ between a pair of electrode plates,
A device in which an EC material such as MoO ₃ , TiO ₂ , Ir ₂ O ₃ and an electrolyte containing ions capable of coloring the EC material is sandwiched is known, and its application to small display devices is being studied. Solid, liquid, and semi-solid electrolytes have been proposed as the electrolyte used here. Looking at these from the perspective of large area and the possibility of sufficient transmittance modulation, solid electrolytes have a slow response and a small modulation width.
Furthermore, since it is a multilayer coating, productivity is low and there are problems in that it is difficult to ensure uniformity of characteristics over a large area. In addition, in the case of liquid electrolyte, it is difficult to use panel technology to prevent leakage of the electrolyte when increasing the area.
Semi-solid electrolytes, especially organic electrolytes, are advantageous in terms of uniformity, workability, and productivity compared to solid electrolytes and liquid electrolytes, but they generally have no ionic conductivity or are small in size. by itself
Many of them do not exhibit EC characteristics or do not exhibit sufficient EC characteristics. Conventionally proposed organic electrolytes with improved ionic conductivity include polyvinyl alcohol containing sulfuric acid, polyacrylamide, ethylene glycol, etc., as described in Japanese Patent Publication No. 54-43387.
GB2005856 specifies polystyrene containing strong acid, weak acid or base, polyethylene sulfonic acid,
Perfluorosulfonic acid, etc., and GB2014326 discloses a copolymer of a monomer containing an acid group and a vinyl monomer. However, conventionally proposed methods for imparting ionic conductivity include adding acids to increase the concentration of proton ions, or adding electrolytes such as bases and salts to increase the mobility of protons. Ta. When something that increases the concentration or mobility of these proton ions is added to an organic electrolyte, the responsiveness of EC when decoloring improves, but it does not have much of a positive effect on the responsiveness when coloring. It was hot. The present inventors have proposed a method for improving responsiveness in order to improve these drawbacks. However, these still have problems in terms of driving voltage, and the inventor of the present invention has discovered the present invention as a result of various studies aimed at lowering this driving voltage. The present invention comprises an electrode plate on which a layer of an electrochromic substance is formed, an electrode plate on which a counter electrode is provided, LiI or I ₂ sandwiched between them, and a polymer compound having an adhesive function or adhesive function. A light control element characterized by comprising an electrolyte containing,
An electrode plate having a layer of an electrochromic substance formed on the electrode, an electrode plate having a counter electrode, and a non-liquid electrolyte containing a polymer compound and an iodine compound having an adhesive or adhesive function sandwiched therebetween. This is a light control transparent body characterized by comprising: By using an iodine compound, the light control element and light control transparent body of the present invention can be driven at low voltage without causing any undesirable side reactions at the counter electrode. Further, by using a substance having a coordination function with metals, particularly a chelating agent, in the electrolyte, coloring is quick and responsiveness is improved. In addition, by adding a decolorizing stabilizer to the electrolyte,
The erasing performance is also improved, and a large change in transmittance is possible. In addition, by using a polymer compound with an adhesive or adhesive function as an electrolyte, the electrolyte can be made semi-solid, so there are almost no problems such as peripheral sealing, injection port sealing, and gap constantization, and 2.
Since the two electrode plates are glued together, there is also the advantage that even if a strong external force is applied to the electrode plate and the electrode plate is damaged, the pieces will not scatter and it will be safe. As the electrochromic substance used in the present invention, the above-mentioned known ones can be used, but usually
It is sufficient if WO ₃ type material is used. Furthermore, this
An EC substance has absorbency within the visible light range when colored, and does not have absorbency at least in part within the visible light range when decolorized. In normal use, it is preferable to have absorbency over the entire visible light range when colored, and to be transparent over the entire visible light range when decolorized. Furthermore, by using an EC substance that absorbs only in a specific wavelength range, or by using a colored filter in combination, patterns, letters, etc. in a specific color tone may be printed. The electrode plate of the present invention can be used as long as the electrode is provided on a transparent plate, and a conductive film of In ₂ O ₃ , SnO ₂ , Au, etc. is provided on a transparent plate such as glass or plastic. This conductive film may normally be provided on the entire surface of the transparent plate, but if necessary, it may be formed in a portion where it is not provided or may be divided into a plurality of parts. A layer of the EC material is formed on the conductive film of one of the electrode plates. The thickness of this layer of EC material may be determined by the coloring density at the time of coloring, but it is generally considered to be about 1,000 to 10,000 Å. In the present invention, since a layer of EC material is formed on the electrode plate, there is no disadvantage that the color disappears as soon as voltage application is stopped, unlike solution type EC dimming elements such as viologen. , can have memory properties. Further, the conductive film of the other electrode plate is used as a counter electrode, but a layer of an EC material that does not absorb within the visible light range may be provided in either coloring or decoloring. The electrolyte of the present invention includes a proton-donating solvent and an iodine compound. Furthermore, in addition to this, substances and/or substances that have a coordinating function to metals as coloring accelerators are added.
Alternatively, it is preferable to use a compound containing Cl or Br as a decoloring stabilizer. Further, by using a polymer compound having an adhesive or adhesive function in combination with this electrolyte, safety is improved and the drawbacks that occur when the electrolyte is liquid or solid do not occur. The proton-donating solvent of the present invention is preferably one with a high boiling point, a low freezing point, and a large dielectric constant, and has 3 carbon atoms.
The above-mentioned alcohols, amide solvents, propylene carbonate, etc. are used. The iodine compound according to the present invention may be one that generates I- ions in the dissociation or redox equilibrium state, and should be present in the electrolyte at a concentration of 5×10 ^-3 mol/
~ It is sufficient to add about a saturation amount, and it reduces the driving voltage of the EC dimming element. Among these, lithium iodide is preferred because of its good responsiveness. In particular, when used in combination with a decoloring stabilizer to be described later, it is highly effective in terms of responsiveness, low voltage drivability, prevention of electrode deterioration, and long life. If the amount added is less than 5 x 10 ^-3 mol/, there will be little improvement effect, and if it exceeds the saturation amount, precipitation will occur, which is not preferable, so it may be determined as appropriate. This iodine compound has a redox effect, and even if the counter electrode is a simple transparent electrode, it causes smooth coloring and fading without causing undesirable side reactions such as electrode dissolution, reduction, or gas generation. have an effect. In particular, when used in combination with a coloring accelerator described below, responsiveness at low voltages is extremely good and sufficient memory properties are produced. As the coloring accelerator of the present invention, an additive having a coordinating function with respect to metal may be used, which improves the coloring response. This is thought to be because the ligand to the electrode metal forms a bond through coordination and facilitates transfer of charge on the electrode surface, resulting in improved responsiveness. Neutral molecules or anions produced by elements in the B, B, and B groups are known as substances that have a coordination function for this metal, and specifically, NR ₃ , PR ₃ , S= CR ₂ , O=CR ₂
(R: Organic substituents such as H, alkyl group, and phenyl group) NH ₂ ^- , F ^- , CN ^-, etc. are exemplified, and although there are differences in degree, the response is improved. Among these, various chelating agents that are polydentate ligands are particularly effective. Chelating agents include β-diketone derivatives such as acetylacetone and benzoylacetone, polyamine compounds such as ethylenediamine and triethylenetetramine, oximes such as dimethylglyoxime, polyhydric carboxylic acids such as oxalic acid, maleic acid, and ethylenediaminetetraacetic acid, and glycine. Examples thereof include amino acids such as thioglycolic acid, thiosalicylic acid, and dimercaptopropanol. Even when these additives are added alone, the responsiveness, especially the responsiveness during coloring, is improved, and it is also preferable to add a substance that increases the concentration or mobility of proton ions in combination. Substances that increase the concentration or mobility of proton ions include inorganic acids such as sulfuric acid, hydrochloric acid, and phosphoric acid, carboxylic acids such as formic acid, acetic acid, benzoic acid, and trichloroacetic acid, and organic sulfonic acids such as benzenesulfonic acid and toluenesulfonic acid. acids, inorganic bases such as LiOH and NaOH, organic bases such as n-propylamine,
Transition metal salts such as chromium acetate, nickel sulfate, iron chloride, organic salts such as ammonium acetate, SiO ₂ ,
Examples include oxide fine particles or sols such as Al ₂ O ₃ and TiO ₂ . This coloring accelerator produces an effect when mixed in an amount of 5 x 10 ^-3 mol/saturation, and if it is less than 5 x 10 ^-3 mol/ the response improvement is insufficient, and if it exceeds the saturation amount, it will cause precipitation. This is not preferable because it causes disadvantages such as the formation of foreign substances. Examples of decoloring stabilizers include lower carboxylic acids containing chlorine and bromine compounds, which can increase the transmittance during decoloring, that is, in a transmitting state. Specific examples include monobromoacetic acid, tribromoacetic acid,
CHBr ₃ and the like may be added in an amount of 1×10 ⁻³ mol/~ to saturation. The polymer compound having an adhesive function or adhesive function used in the present invention is not particularly limited, but may be one that maintains a constant interval between transparent bodies and makes it difficult to cause damage by making the electrolyte non-liquid. Even if it is damaged, the electrolyte will not flow out. Specifically, polyacrylic acid, polymethacrylic acid and their salts, esters, amides, polysulfonic acids, polyvinyl alcohol,
There are adhesive polymers having polar groups such as polyvinyl acetate, polyvinyl acetal, nylon, polyurethane, melamine, urea resin, and polyaminosilane, and copolymers of monomers constituting these polymers and other monomers. In particular, polyvinyl acetal, represented by polyvinyl butyral, has excellent adhesiveness, durability, and responsiveness, is durable over a large area, and can produce the high penetration resistance seen in laminated glass. It can have both a dimming function and a safety function. In this way, by making the electrolyte into an elastic semi-solid with strong durability, the peripheral sealing part of the element and the sealing part of the injection port are much simpler or simpler than when using liquid electrolyte. It is unnecessary, does not cause disadvantages such as deterioration due to liquid leakage and expansion of the gap between transparent bodies due to deflection, has high penetration resistance, and is excellent in safety. In order to use this polymer compound in the light control transparent body of the present invention, if this polymer compound is soluble in a solvent, a solution of an organic substance containing an additive is applied to the electrode plate using a meniscus coating method or a pulling method. EC is applied to a specified thickness using a method such as a spray method, a casting method, a spinner method, etc., and then formed using a vacuum evaporation method, etc.
It can be obtained by press-bonding an electrode plate with a substance film, or, if the polymer compound can be formed into a film, by making a film containing additives in advance and press-bonding it with both electrode plates. If the polymer compound is not soluble in a solvent, it is better to use a solution of monomers with additives and a curing agent added thereto to obtain an appropriate viscosity. During crimping, heat and pressure can be applied as necessary. In addition, suitable plasticizers, thickeners, stabilizers, fillers, pigments, etc. may be added to improve handling properties during coating and pressure bonding of the resin. Furthermore, a plastic film, glass fiber, glass beads, etc. of a constant thickness may be used around the periphery or within the plane to make the spacing between the electrode plates constant. The end surface of the panel formed in this way is free from moisture.
In order to prevent the intrusion of oxygen and the like, it is preferable to use a sealant such as epoxy resin, silicone resin, butyl rubber, thiocol, etc. to seal the container. When using the light control element or the light control transparent body of the present invention, glass, hard plastic, or hard-coated plastic is used as the transparent body on which the electrodes are provided, and it can be used as it is as a light control window in buildings, vehicles, etc. Moreover, by using a flexible plastic film as the transparent body, a flexible light control element or a light control combined transparent body can be manufactured. In this case, it can be attached to a glass plate or the like and placed inside a pair of glass, or it can be made into an adhesive type EC element to the base material by applying a scratch-resistant coating to the plastic film on the surface. can. Although only a conductive film may be used as the counter electrode, low voltage responsiveness is improved by providing a thin film of a transition metal compound such as a transition metal oxide, nitride, or sulfide. As specific examples, FeO, NiO, and CuO are particularly effective. Taking WO ₃ as an example, the coloring and fading mechanism of EC substances consists of the reversible reaction shown below. By setting the display pole to negative, the reaction progresses to the right, resulting in coloration, and by turning the display pole to positive. The reaction progresses to the left side and the color disappears. Furthermore, elements using EC materials have memory properties, and when the display electrode is placed in a floating state, it retains its previous state for a considerable period of time, and does not consume power. WO ₃ +xH ⁺ +Xe ^- Hx ⁺ WO ₃ ex ^- Also, for the counter electrode, an example of In ₂ O ₃ is shown,
The reaction is shown to proceed to the right when the counter electrode is made positive in order to correspond to the display electrode. Also, Ml
represents an iodine compound, and Ke represents a chelating agent. 2×Ml−2xe ^- xI ₂ +2xM ⁺ In ₂ O ₃ +xOH ^- +xH ⁺ Ke ^- -xe ^- In ₂ O ₃ Kex + xH ₂ O In this way, the iodine compound in the present invention can be used alone for redox reaction and drive. It works to lower the voltage. In particular, when an iodine compound and a color accelerator are used in combination, it becomes possible to significantly reduce the driving voltage, and it becomes possible to drive with only about 1V. Example 1 On a 10 cm square glass plate as an extremely transparent display material
A substrate on which In ₂ O ₃ was vacuum evaporated and WO ₃ was vacuum evaporated thereon was used. In ₂ O ₃ was vacuum evaporated on a 10 cm square glass plate as the counter electrode, and the solvent butyl alcohol was used as the electrolyte. , color accelerator thiosalicylic acid 1×10 ^-3 mol/, decolorization stabilizer tribromoacetic acid 5×10 ^-2 mol/and iodine compound 1×
10 ^-3 mol/mixture was used. The graph numbers of the iodine compound, driving voltage, and coloring/decoloring time are shown in Table 1. Note that No. 1 and No. 2 in Table 1 are comparative examples. Further, the vertical axis of the graph indicates transmittance as 100%, and the horizontal axis indicates time in minutes. Example 2 and subsequent examples are shown in the same manner, and the line on the left side of each graph is 0 to 3.
The line on the right shows the change in transmittance when coloring is achieved by applying a voltage for 3 minutes, and the line on the right shows the change in transmittance when a voltage of the opposite polarity is applied to erase the color, with 3 minutes being 0 minutes.

[Table] In examples where iodine compounds are not used, the driving voltage is
If it is 1.5V, the transmittance will change from 20% to 80%,
In the example shown in No. 2 (Fig. 2), since the voltage was 1 V, the transmittance did not fall below 50% even when colored. On the other hand, Nos. 3 to 3 which are examples of the present invention
No. 9 had good coloring and fading characteristics, and a change in transmittance of 20% to 80% was obtained within 3 minutes at a driving voltage of 1V. In addition, an example is shown in which only lithium iodide is added to the electrolyte and thiosalicylic acid, which is a color accelerator, is not used.
No. 10, and the results are shown in FIG. As is clear from the graph, this result showed that the coloring response was worse than No. 4, but No. Compared to .2, the response at low voltage was better. Example 2 Table 2 shows an example in which 1×10 ⁻³ mol/LiI was used as the iodine compound and the coloring accelerator and decoloring stabilizer were variously changed. The amount of color accelerator added is 1
×10 ^-1 mol/, the amount of decolorizing stabilizer added is 5×
10 ^-2 mol/, and all other conditions were the same as in Example 1. This result is shown in Figures 11 to 15.
As shown in the figure, excellent coloring/decoloring properties were obtained in all cases.

[Table] Example 3 A light control transparent body was basically the same as No. 4 of Example 1, but added 30% of No. 16 polyvinyl butyral and 30% of No. 17 polyacrylic acid to the electrolyte. Manufactured. The coloring and fading properties were excellent as shown in FIGS. 16 and 17, and high penetration resistance was obtained, similar to that of laminated glass.
In addition, since the electrolyte in each of these was non-liquid, they were highly durable and did not cause liquid leakage. Example 4 This is an example that is basically the same as No. 4 of Example 1, but uses a transition metal oxide layer formed on the counter electrode, and No. 18FeO, No. 19 NiO, and No. 20 CuO, respectively.
In this example, it is installed at a thickness of 500A, and at a driving voltage of 1V, it is No.4.
18 to 20 show the coloring/decoloring characteristics obtained under a driving voltage of 0.75 V, which is a more severe condition, in order to show the coloring/decoloring characteristics similar to those shown in FIG. In these examples, the driving voltage is 0.75V, so the coloring characteristics are slightly inferior, but Example No. 21 without a transition metal oxide layer
When compared with FIG. 21, which is an example in which the device (the element is the same as No. 4) was driven at 0.75V, the low voltage drive characteristics were better. Comparative Example Instead of the iodine compound of the present invention, No.22LiClO ₄ ,
1 mol/each of No.23LiBr and No.24H ₂ SO ₄ was added.
Using the same device as No. 2, its coloring and fading characteristics were measured, and the results are shown in FIGS. 22 to 24. Although these exhibited slightly better coloring and decoloring properties than additives, their coloring properties were only insufficient at a driving voltage of 1V. Example 5 No. 25 (I ₂ ), which is an example of the case where the color accelerator and decoloring stabilizer of No. 3 and No. 5 to No. 9 of Example 1 are not included,
No.26 (MnI ₂ ), No.27 (NiI ₂ ), No.28 (ZnI ₂ ), No.29
(NH ₄ I) and No. 30 (CH ₂ ICOOH), graphs of coloring/decoloring time are shown in FIGS. 25 to 30. The driving voltage is
It was designated as IV. Example 6 No. 10 (LiI) of Example 1 and No. 29 of Example 5
The concentration of the iodine compound in the example of (NH ₄ I) is 0.75M/
Figures 31 and 32 show graphs of the coloring and fading time of No. 31 (LiI) and No. 32 (NH ₄ I), which are examples in which 30% polyvinyl butyral was added to the electrolyte. The driving voltage was set to IV. As described above, the present invention has good coloring/decoloring properties at low voltages, and in particular, by making the electrolyte semi-solid using an adhesive or sticky polymer compound, it has excellent properties that exhibit high penetration resistance like laminated glass. It can be used in various ways as a light control element by using other materials and additives as necessary.

[Brief explanation of drawings]

FIGS. 1 to 32 are graphs showing the coloring/decoloring characteristics of Examples and Comparative Examples of the present invention.

Claims (1)

[Claims] 1. An electrode plate with an electrochromic material layer formed on the electrode, an electrode plate with a counter electrode, LiI or I ₂ sandwiched between them, and a polymer having an adhesive function or adhesive function. A light control element comprising an electrolyte containing a molecular compound. 2. The light control element according to claim 1, wherein the electrolyte includes a substance having a coordination function with respect to a metal. 3. The light control element according to claim 2, wherein the substance having a coordination function with respect to metal is a chelating agent. 4 Claims 1 to 3 in which the electrolyte contains a decoloring stabilizer made of a lower carboxylic acid containing chlorine
The light control device according to any one of paragraphs. 5. The light control element according to any one of claims 1 to 3, wherein the electrolyte contains a decoloring stabilizer made of a bromine compound. 6 An electrode plate with a layer of electrochromic substance formed on the electrode, an electrode plate with a counter electrode provided thereon, and a non-liquid containing a polymer compound having an adhesive or adhesive function and _I2 or LiI sandwiched between them. A light-adjustable transparent body characterized by comprising a transparent electrolyte. 7. The light control transparent body according to claim 6, wherein the non-liquid electrolyte contains a substance having a coordination function with respect to a metal. 8. The light control transparent body according to claim 7, wherein the substance having a coordination function with respect to metal is a chelating agent. 9 Claim 6 in which the non-liquid electrolyte contains a decoloring stabilizer made of a lower carboxylic acid containing chlorine
The light control transparent body according to any one of Items 1 to 8. 10. The light control transparent body according to any one of claims 6 to 8, wherein the non-liquid electrolyte contains a decoloring stabilizer made of a bromine compound.