JP2017026750A - Electrochromic device, light control glasses, and method for manufacturing the electrochromic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrochromic device that can prevent crack generation in an electrode layer and has excellent appearances and operating characteristics.SOLUTION: The electrochromic device includes: a first substrate 11; a first electrode layer 12 on the first substrate 11; an electrochromic layer 13 on the first electrode layer 12; a second substrate 16, facing the first substrate 11; a second electrode layer 15 on a side of the second substrate 16 which is near the first substrate 11; and an electrolyte layer 14 between the first electrode layer 12 and the second electrode layer 15. The electrochromic device has such a three-dimensional curved shape that the first substrate 11 forms a convex extending in the direction of the first electrode layer 12 and the first substrate 11 is thinner than the second substrate 16.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrochromic element, dimming glasses, and a method for manufacturing an electrochromic element.

  A phenomenon in which a redox reaction occurs reversibly and a color changes reversibly by applying a voltage is called electrochromism. A device using this electrochromism is an electrochromic device. Many studies have been conducted on electrochromic devices to date that applications derived from the characteristics of electrochromism can be realized.

  Electrochromic materials used in electrochromic devices include organic materials and inorganic materials. An organic material is promising as a color display device because it can generate various colors depending on its molecular structure. On the other hand, inorganic materials have problems in color control. However, practical application to light control glass and ND filters is being studied as an application that uses this feature and has an advantage of low color saturation.

  In such an electrochromic device, generally, an electrochromic material is formed between two electrodes facing each other, and an oxidation-reduction reaction is performed in a configuration in which an ion conductive electrolyte layer is filled between the electrodes. Since electrochromic is an electrochemical phenomenon, the performance (ionic conductivity, etc.) of the electrolyte layer affects the response speed and the memory effect of color development. When the electrolyte layer is in the form of a liquid in which the electrolyte is dissolved in a solvent, it is easy to obtain fast responsiveness. However, improvements in solidification and gelation have been studied in terms of device strength and reliability.

That is, conventionally, an electrolytic solution is used in a battery or an electrochromic device as an electrochemical element. For this reason, not only the leakage of the electrolyte and the drying of the battery due to the volatilization of the solvent, but also the unevenness of the electrolyte in the battery container caused an increase in internal impedance and an internal short circuit.
Especially when an electrochromic device is used for dimming glass or display applications, it is necessary to seal at least one direction with a transparent material such as glass or plastic. It is difficult, and leakage and volatilization of the electrolyte become a larger problem.

As a method for solving the above-described drawbacks, it has been proposed to use a polymer solid electrolyte. Examples of the solid polymer electrolyte include a solid solution of a matrix polymer containing an oxyethylene chain or an oxypropylene chain and an inorganic salt. These are completely solid and excellent in processability, but have low electrical conductivity.
Therefore, in order to improve the electrical conductivity of the polymer solid electrolyte, a method of dissolving the organic electrolyte in the polymer to make it semi-solid, or a liquid monomer added with the electrolyte is polymerized to include the electrolyte A method of forming a crosslinked polymer has been proposed.
However, none of these proposed technologies has reached a practical level.

By the way, in general, an electrochromic device is manufactured by forming an electrochromic material between two opposing electrodes and then bonding them together via an electrolyte layer capable of ion conduction. Therefore, although it is easy to make a flat shape, there is a problem that it cannot be easily applied to applications such as a three-dimensional surface (3D surface) and a curved surface. For example, if it can be applied to a three-dimensional (3D) shape such as a lens, the applicable range is widened as an optical application.
However, optical defects are likely to occur due to the curved surface accuracy and position accuracy of the two substrates to be bonded. Furthermore, in the case of a spectacle lens, it is necessary to adjust the frequency in accordance with the user, and preparing a large number of substrates having different curved shapes becomes a problem for mass production.

If such an electrochromic device can be manufactured without a bonding process, the above problem can be solved. However, it has been difficult to form an electrochromic device on a support by a thin film process in the prior art. That is, when an electrode is formed on the electrolyte layer in order to omit the bonding process, there is a problem that the response speed is slow as described above when an all-solid electrolyte layer is used. Furthermore, when an organic material layer is used as the all-solid electrolyte layer, there is a problem that the electric resistance of the electrode layer formed on the electrolyte layer tends to be high, and the redox drive cannot be performed normally. In particular, when an oxide layer such as ITO, IZO, SnO ₂ , AZO, GZO formed by vacuum film formation, which is generally adopted as a transparent electrode, is formed on the surface of an organic film, transparency and electrical conduction There is a problem that it is difficult to balance the degree.

  On the other hand, when an inorganic material layer is used as the all-solid electrolyte layer, it is limited to an inorganic electrochromic compound. As an example of using the inorganic electrochromic compound, an electrochromic element having a structure in which a reduction color development layer and an oxidation color development layer are arranged to face each other with a solid electrolyte layer interposed therebetween can be given.

In the electrochromic device, the reduced color layer is made of a material containing tungsten oxide and titanium oxide, and the oxidized color layer is made of a material containing nickel oxide. Further, a transparent intermediate composed of a metal oxide or metal other than nickel oxide or a composite of metal oxide and metal other than nickel oxide as a main component between the oxidation coloring solid electrolyte layer. An electrochromic element in which layers are arranged has been proposed (see, for example, Patent Document 1). According to this proposal, it is described that by forming the intermediate layer, the repetition characteristics and the responsiveness are improved, and the color development driving can be performed in a few seconds.
However, the proposed electrochromic device has a complicated structure, and it is difficult to increase the size of the inorganic compound layer by vacuum film formation, and this causes an increase in cost. In addition, the thermal effect of the film forming process is unavoidable, and the substrate is likely to be limited to a heat resistant material such as glass. Furthermore, there is a problem that the inorganic electrochromic reaction is easily affected by moisture and the color is limited to blue.

On the other hand, an organic electrochromic device that can be manufactured without a bonding process has been proposed (see Patent Document 2). According to this, it is possible to realize a 3D-shaped electrochromic device.
However, Patent Document 2 also has a problem that the number of layers coated on the support is large, coating defects are likely to occur, haze is increased, and the film is easily peeled off. On the other hand, it is conceivable to form a curved surface by thermoforming a resin substrate including an electrode layer. However, when the substrates are bonded and bent into a three-dimensional curved surface, cracks occur in the electrode layer, and the appearance There is a problem of getting worse. In addition, the resistance value of the electrode increases due to the crack, and there is a problem that the electrochromic element cannot be driven with a desired driving voltage.

  The present invention has been made to solve the above-described problems, and an object thereof is to achieve the following object. That is, an object of the present invention is to provide an electrochromic element that can suppress the occurrence of cracks in an electrode layer and has good appearance and operating characteristics.

  In order to solve the above problems, the present invention provides at least a first substrate, a first electrode layer formed on the first substrate, and an electrochromic layer formed on the first electrode layer. A second substrate facing the first substrate and disposed on the first electrode layer side, and a second substrate formed on the first substrate side surface of the second substrate. And an electrolyte layer formed between the first electrode layer and the second electrode layer, the electrochromic element having a three-dimensional curved shape, The three-dimensional curved surface shape is a shape in which the first substrate is convex in the direction of the first electrode layer, and the thickness of the first substrate is thinner than the second substrate.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the crack in an electrode layer can be suppressed, and the electrochromic element with a favorable external appearance and an operational characteristic can be provided.

It is a cross-sectional schematic diagram in an example of the electrochromic element which concerns on this invention. It is a cross-sectional schematic diagram in the other example of the electrochromic element which concerns on this invention. It is a cross-sectional schematic diagram in the other example of the electrochromic element which concerns on this invention. It is a schematic diagram in the other example of the electrochromic element which concerns on this invention. It is a flowchart of the manufacturing process in an example of the electrochromic element which concerns on this invention.

  Hereinafter, an electrochromic device, dimming glasses, and a method for manufacturing an electrochromic device according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and any aspect is possible. As long as the functions and effects of the present invention are exhibited, the scope of the present invention is included.

  The present invention includes at least a first substrate, a first electrode layer formed on the first substrate, an electrochromic layer formed on the first electrode layer, and the first substrate. A second substrate that is opposed and disposed on the first electrode layer side, a second electrode layer formed on a surface of the second substrate on the first substrate side, and the first substrate An electrochromic element having an electrolyte layer formed between the second electrode layer and the second electrode layer, wherein the electrochromic element has a three-dimensional curved surface shape. One substrate has a shape protruding in the direction of the first electrode layer, and the thickness of the first substrate is thinner than that of the second substrate.

(Electrochromic device)
<First Embodiment>
A configuration example of one embodiment of the electrochromic device of the present invention is shown in FIG. As shown in FIG. 1A, a first electrode layer 12, an electrochromic layer 13, and an insulating layer 17 are formed over the first substrate 11. As shown in FIG. 1B, a second electrode layer 15 is formed on the second substrate 16, and as shown in FIG. 1C, these first substrate 11 and An electrolyte layer 14 is filled and bonded between the electrode layers of the second substrate 16 to form an electrochromic element.

  In FIG. 1D, the first substrate 11 and the first electrode layer 12, the electrochromic layer 13, and the insulating layer 17 formed on the first substrate 11 are denoted by reference numeral 21. The second substrate 16 and the second electrode layer 15 formed on the second substrate are denoted by reference numeral 22. FIG. 1D shows an example in the case of heat processing and curved surface processing, where a three-dimensional curved surface shape is formed and a desired curved surface shape is formed.

  The present invention is characterized in that the thickness of the first substrate 11 is thinner than that of the second substrate 16. Thereby, since the stress concerning the electrode layer bent convexly can be made small, the crack which generate | occur | produces at the time of curved surface processing can be prevented.

  Hereinafter, each component which comprises the electrochromic element which concerns on this embodiment is demonstrated in detail.

<Board>
As the first substrate 11 and the second substrate 16, a well-known thermoformable resin material can be used as it is. For example, a resin substrate such as polycarbonate resin, acrylic resin, polyethylene, polyvinyl chloride, polyester, epoxy resin, melamine resin, phenol resin, polyurethane resin, or polyimide resin may be used.
In addition, the surfaces of the first substrate 11 and the second substrate 16 may be coated with a transparent insulating layer, an antireflection layer, or the like in order to improve water vapor barrier properties, gas barrier properties, and visibility.

  When the substrate on which the electrode layer is formed is curved, it has been found that cracks are more likely to occur when the electrode layer is bent to be convex than when the electrode layer is bent to be concave. Since the electrode layer is weaker than the compressive stress to the tensile stress, it has been found that it is effective to reduce the thickness of the substrate on which the electrode layer to which the tensile stress is applied becomes convex. Therefore, by making the thickness of the substrate bent in the direction in which the electrode layer is convex thinner than the substrate bent in the direction in which the electrode layer is concave, the electrode can be configured not to easily crack.

  In the present embodiment, when the region sandwiched between the first substrate 11 and the second substrate 16 is the inside, the first substrate 11 has a convex shape in the inward direction, and the second substrate 16 is in the inward direction. It has a concave shape. Therefore, the first substrate 11 has a convex surface on which the electrode layer is formed, and the second substrate 16 has a concave surface on which the electrode layer is formed. As described above, by making the thickness of the substrate (first substrate 11) having a convex surface on which the electrode layer is formed thinner than the substrate (second substrate 16) having a concave surface, the electrode is formed during curved surface processing. The stress applied to the layer can be reduced. Thereby, generation | occurrence | production of the crack in an electrode layer can be suppressed, the electrochromic element with a favorable external appearance and an operating characteristic can be obtained, and the electrochromic element in which the desired curved surface shape was formed can be obtained.

Although the thickness of a board | substrate can be changed suitably, the range of 0.2 mm-1.0 mm in which the bending process by thermoforming is easy is preferable.
The ratio of the first substrate 11 to the second substrate 16 is preferably (thickness of the first substrate 11) / (thickness of the second substrate 16) = 0.2 to 0.9.

<First electrode layer and second electrode layer>
The material of the first electrode layer 12 and the second electrode layer 15 is not particularly limited as long as it is a transparent and conductive material, and can be appropriately selected according to the purpose. Examples thereof include indium oxide doped with tin (hereinafter referred to as ITO), tin oxide doped with fluorine (hereinafter referred to as FTO), tin oxide doped with antimony (hereinafter referred to as ATO), and the like. Among these, any of indium oxide (hereinafter referred to as In oxide), tin oxide (hereinafter referred to as Sn oxide), and zinc oxide (hereinafter referred to as Zn oxide) formed by vacuum film formation. An inorganic material including one is preferable.

The In oxide, Sn oxide, and Zn oxide are materials that can be easily formed by a sputtering method, and can obtain good transparency and electrical conductivity.
Among these, InSnO, GaZnO, SnO, In ₂ O ₃ and ZnO are particularly preferable. Furthermore, transparent network electrodes such as silver, gold, carbon nanotube, and metal oxide, and composite layers thereof are also useful.

  There is no restriction | limiting in particular in the thickness of the said electrode layer, It can adjust so that an electrical resistance value required for an electrochromic oxidation-reduction reaction may be obtained, for example, when using ITO, 50 nm-500 nm are preferable.

  Examples of the method for producing the electrode layer include vacuum film forming methods such as a vacuum deposition method, a sputtering method, and an ion plating method. If the display electrode material can be applied and formed, spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating method, slit coating method, Various printing methods such as a capillary coating method, a spray coating method, a nozzle coating method, a gravure printing method, a screen printing method, a flexographic printing method, an offset printing method, a reverse printing method, and an inkjet printing method can also be used.

  Examples of the method for forming fine irregularities on the surface of the electrode layer include a sand blast method, a dry etching method, a wet etching method, a laser ablation method, and a colloidal lithography method. Among these, a colloidal lithography method which is a simple method and can be used for a spin coater used when forming an electrochromic layer or an insulating layer is preferable.

<Electrochromic layer>
The electrochromic layer 13 includes an electrochromic material, and further includes other components as necessary.
As the electrochromic material, either an inorganic electrochromic compound or an organic electrochromic compound may be used. In addition, a conductive polymer known to exhibit electrochromism can also be used.

Examples of the inorganic electrochromic compound include tungsten oxide, molybdenum oxide, iridium oxide, and titanium oxide.
Examples of the organic electrochromic compound include viologen, rare earth phthalocyanine, and styryl.
Examples of the conductive polymer include polypyrrole, polythiophene, polyaniline, or derivatives thereof.

  As the electrochromic layer 13, it is preferable to use a structure in which an organic electrochromic compound is supported on conductive or semiconductive fine particles. Specifically, it is a structure in which fine particles having a particle size of about 5 nm to 50 nm are sintered on the electrode surface, and an organic electrochromic compound having a polar group such as phosphonic acid, carboxyl group, silanol group or the like is adsorbed on the surface of the fine particles. . The structure utilizes a large surface effect of fine particles and efficiently injects electrons into the organic electrochromic compound. Therefore, the structure responds faster than a conventional electrochromic device.

Furthermore, since a transparent film can be formed as a display layer by using fine particles, a high color density of the electrochromic dye can be obtained.
A plurality of types of organic electrochromic compounds can be supported on conductive or semiconductive fine particles.

Specific examples of the electrochromic material include polymer-based and dye-based electrochromic compounds such as azobenzene, anthraquinone, diarylethene, dihydroprene, dipyridine, styryl, styrylspiropyran, spirooxazine, Spirothiopyran, thioindigo, tetrathiafulvalene, terephthalic acid, triphenylmethane, triphenylamine, naphthopyran, viologen, pyrazoline, phenazine, phenylenediamine, phenoxazine, phenothiazine, phthalocyanine And low molecular organic electrochromic compounds such as fluoran, fulgide, benzopyran, and metallocene, and conductive polymer compounds such as polyaniline and polythiophene.
Among these, a viologen compound or a dipyridine compound is preferable from the viewpoint of a low color developing / erasing potential and a good color value.

Examples of the viologen compound include compounds described in Japanese Patent No. 39555641 and Japanese Patent Application Laid-Open No. 2007-171781.
Examples of the dipyridine-based compound include compounds described in JP 2007-171781 A and JP 2008-116718 A.
Among these, a dipyridine compound represented by the following general formula (1) is preferable from the viewpoint of exhibiting a good color value.

However, in said general formula (1), R1 and R2 represent each independently the C1-C8 alkyl group which may have a substituent, or an aryl group, and at least one of R1 and R2 is It has a substituent selected from COOH, PO (OH) ₂ , and Si (OC _k H _{2k + 1} ) ₃ (where k is 1 to 20). X represents a monovalent anion. For example, X is not particularly limited as long as it is stably paired with a cation moiety, but Br ion (Br ⁻ ), Cl ion (Cl ⁻ ), ClO ₄ ion ( ClO ₄ ⁻ ), PF ₆ ion (PF ₆ ⁻ ), BF ₄ ion (BF ₄ ⁻ ) and the like. n, m, and l represent 0, 1, or 2. A, B, and C each independently represent a C 1-20 alkyl group, aryl group, or heterocyclic group that may have a substituent.

As the metal complex-based or metal oxide-based electrochromic compound, inorganic electrochromic compounds such as titanium oxide, vanadium oxide, tungsten oxide, indium oxide, iridium oxide, nickel oxide, and Prussian blue are used.
There is no restriction | limiting in particular as electroconductive or semiconductive fine particle, Although it can select suitably according to the objective, A metal oxide is preferable.

  Examples of the metal oxide materials include titanium oxide, zinc oxide, tin oxide, zirconium oxide, cerium oxide, yttrium oxide, boron oxide, magnesium oxide, strontium titanate, potassium titanate, barium titanate, calcium titanate, and oxidation. Metal oxides mainly composed of calcium, ferrite, hafnium oxide, tungsten oxide, iron oxide, copper oxide, nickel oxide, cobalt oxide, barium oxide, strontium oxide, vanadium oxide, aluminosilicate, calcium phosphate, aluminosilicate, etc. are used. . These may be used individually by 1 type and may use 2 or more types together.

In view of electrical properties such as electrical conductivity and physical properties such as optical properties, one selected from titanium oxide, zinc oxide, tin oxide, zirconium oxide, iron oxide, magnesium oxide, indium oxide, tungsten oxide, or When these mixtures are used, it is possible to display colors with excellent response speed of color development and decoloration.
In particular, when titanium oxide is used, it is possible to display a color with an excellent response speed of color development and decoloration.

In addition, the shape of the conductive or semiconductive fine particles is not particularly limited, but a shape having a large surface area per unit volume (hereinafter referred to as a specific surface area) is used in order to efficiently carry the electrochromic compound. .
For example, when the fine particle is an aggregate of nanoparticles, it has a large specific surface area, so that the electrochromic compound is more efficiently supported and the display contrast ratio of color development and decoloration is excellent.

There is no restriction | limiting in particular in the thickness of the electrochromic layer 13, Although it can select suitably according to the objective, 0.2 micrometer-5.0 micrometers are preferable. When the thickness is less than 0.2 μm, it may be difficult to obtain a color density, and when it exceeds 5.0 μm, the manufacturing cost increases and the visibility may be easily lowered by coloring.
Although the electrochromic layer 13 and the conductive or semiconductive fine particle layer can be formed by vacuum film formation, it is preferably formed by coating as a particle-dispersed paste from the viewpoint of productivity.

<Electrolyte layer>
The electrolyte layer 14 is preferably a solid electrolyte layer, and is formed as a film holding the electrolyte in light or thermosetting resin. Furthermore, it is preferable to mix inorganic particles for controlling the thickness of the electrolyte layer 14. Such an electrolyte layer is preferably a film cured with light or heat after being coated on the electrochromic layer 13 as a mixed solution of the inorganic fine particles, curable resin, and electrolyte. Alternatively, a porous inorganic fine particle layer may be formed in advance and then coated as a mixed solution of a curable resin and an electrolyte so as to penetrate into the inorganic fine particle layer, and then a film cured by light or heat. Further, when the electrochromic layer is a layer in which an electrochromic compound is supported on conductive or semiconducting nanoparticles, after coating as a mixed solution of a curable resin and an electrolyte so as to penetrate into the electrochromic layer 13 A film cured with light or heat can also be used.

As the electrolytic solution, a liquid electrolyte such as an ionic liquid or a solution obtained by dissolving a solid electrolyte in a solvent is used.
As the electrolyte material, for example, inorganic ion salts such as alkali metal salts and alkaline earth metal salts, quaternary ammonium salts, acids, and alkali supporting salts can be used. Specifically, LiClO ₄ , LiBF ₄ , LiAsF ₆ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ COO, KCl, NaClO ₃ , NaCl, NaBF ₄ , NaSCN, KBF ₄ , Mg (ClO ₄ ) ₂ , Mg ( BF ₄ ) _{2 and the} like.

The ionic liquid is not particularly limited and may be any substance that is generally studied and reported.
An organic ionic liquid has a molecular structure that exhibits a liquid in a wide temperature range including room temperature.
The molecular structure is composed of a cation component and an anion component.
Examples of the cationic component include imidazole derivatives such as N, N-dimethylimidazole salt, N, N-methylethylimidazole salt, N, N-methylpropylimidazole salt; N, N-dimethylpyridinium salt, N, N- Examples include aromatic salts such as pyridinium derivatives such as methylpropylpyridinium salts; aliphatic quaternary ammonium compounds such as tetraalkylammonium such as trimethylpropylammonium salt, trimethylhexylammonium salt, and triethylhexylammonium salt.

The anion component is preferably a compound containing fluorine in terms of stability in the atmosphere. For example, BF ₄ ⁻ , CF ₃ SO ₃ ⁻ , PF ₄ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , B ( CN ₄₎ ^-, and the like. An ionic liquid formulated by a combination of these cationic components and anionic components can be used.

  Examples of the solvent include propylene carbonate, acetonitrile, γ-butyrolactone, ethylene carbonate, sulfolane, dioxolane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,2-dimethoxyethane, 1,2-ethoxymethoxyethane, and polyethylene glycol. Alcohols and mixed solvents thereof can be used.

  Examples of the cured resin include common materials such as acrylic resins, urethane resins, epoxy resins, vinyl chloride resins, ethylene resins, melamine resins, phenol resins, and other photocurable resins, and thermosetting resins. A material having high compatibility with the electrolyte is preferable. As such a structure, derivatives of ethylene glycol such as polyethylene glycol and polypropylene glycol are preferable. Further, as the curable resin, it is preferable to use a photocurable resin. This is because the device can be manufactured at a low temperature and in a short time compared to thermal polymerization or a method of thinning the film by evaporating the solvent.

  A particularly preferred combination is an electrolyte layer composed of a solid solution of a matrix polymer containing oxyethylene chains or oxypropylene chains and an ionic liquid. By using this configuration, it is easy to achieve both hardness and high ionic conductivity.

  The inorganic fine particle is not particularly limited as long as it is a material that can form a porous layer and hold the electrolyte and the cured resin. However, in terms of stability of electrochromic reaction and visibility, it is insulated. A material having high properties, transparency and durability is preferable. Specific examples of the material include oxides or sulfides such as silicon, aluminum, titanium, zinc, and tin, or mixtures thereof.

  There is no restriction | limiting in particular in the magnitude | size (average particle diameter) of the said inorganic fine particle, Although it can select suitably according to the objective, 10 nm-10 micrometers are preferable, and 10 nm-100 nm are more preferable.

<Protective layer>
The protective layer is formed so as to physically and chemically protect the side portion of the electrochromic device. The protective layer can be formed by, for example, applying an ultraviolet curable or thermosetting insulating resin or the like so as to cover the side surface and / or the upper surface, and then curing. Moreover, it is more preferable to use a laminated protective layer of a cured resin and an inorganic material. By using a laminated structure with an inorganic material, barrier properties against oxygen and water are improved.

  As the inorganic material, a material having high insulation, transparency, and durability is preferable, and specific materials include oxides or sulfides such as silicon, aluminum, titanium, zinc, and tin, or a mixture thereof. Can be mentioned. These films can be easily formed by a vacuum film forming process such as sputtering or vapor deposition.

  There is no restriction | limiting in particular in the thickness of the said protective layer, Although it can select suitably according to the objective, 0.5 micrometer-10 micrometers are preferable.

<Second Embodiment>
Next, other embodiments of the electrochromic device according to the present invention will be described. A description of parts common to the above embodiment may be omitted.

  The electrochromic device according to this embodiment includes a deterioration preventing layer 24 that is in contact with the second electrode layer 16 and performs an electrochemical reaction opposite to the oxidation-reduction reaction of the electrochromic layer 13. A configuration example of the electrochromic device according to the present embodiment is shown in FIG. As shown in FIG. 2A, the second electrode layer 15 is formed on the second substrate 16, and the deterioration preventing layer 24 is formed thereon. This is bonded to the first substrate 11 as shown in FIG. 1A via the electrolyte layer 14 to obtain the configuration shown in FIG. On the other hand, the electrochromic element shown in FIG. 2C is obtained by processing the curved surface. In FIG. 2C, the first substrate 11 side is collectively indicated by reference numeral 31, and the second substrate 16 side is collectively indicated by reference numeral 32. Details will be described below.

<Deterioration prevention layer>
The role of the deterioration preventing layer 24 is preferably to perform a chemical reaction opposite to that of the electrochromic layer 13 and to prevent the second electrode layer 15 from corroding or deteriorating due to an irreversible oxidation-reduction reaction in balance of charge. Suppress. As a result, the repeated stability of the electrochromic device is improved. Note that the reverse reaction includes not only the case where the deterioration preventing layer 24 is oxidized and reduced, but also that it functions as a capacitor.

  The material of the deterioration preventing layer 24 is not particularly limited as long as it is a material that plays a role of preventing corrosion of the first electrode layer 12 and the second electrode layer 15 due to irreversible oxidation-reduction reaction. As the material of the deterioration preventing layer 24, for example, antimony tin oxide, nickel oxide, titanium oxide, zinc oxide, tin oxide, or a conductive or semiconductive metal oxide containing a plurality of them can be used. Furthermore, when coloring of the deterioration preventing layer 24 does not become a problem, the same material as the above-described electrochromic material can be used.

  In particular, when an electrochromic element is manufactured as an optical element such as a lens that requires transparency, it is preferable to use a highly transparent material as the deterioration preventing layer. As such a material, it is preferable to use n-type semiconducting oxide fine particles (n-type semiconducting metal oxide). As a specific example, titanium oxide, tin oxide, zinc oxide, compound particles containing a plurality of them, or a mixture composed of particles having a primary particle diameter of 100 nm or less can be used.

  Furthermore, when these deterioration preventing layers 24 are used, it is preferable that the electrochromic layer 13 is a material that changes color by an oxidation reaction. As a result, the electrochromic layer 13 undergoes an oxidation reaction, and at the same time, the n-type semiconductor metal oxide is easily reduced (electron injection), and the driving voltage can be reduced.

In such a form, a particularly preferred electrochromic material is an organic polymer material. The film can be easily formed by a coating process or the like, and the color can be adjusted and controlled by the molecular structure. Specific examples of these organic polymer materials include “Chemistry of Materials review 2011.23, 397-415 Navigating the Color Palette of Solution-Processable Electrochemical Polymers 29, Reynol76, Reyolde 30”. "Polymer journal, Vol. 41, No. 7, Electrochromic Organic Material Hybrid Polymers" and the like.
Examples of these organic polymer materials include poly (3,4-ethylenedioxythiophene) based materials, complex polymers of bis (terpyridine) s and iron ions, and the like.

  On the other hand, examples of the material of the highly transparent p-type semiconducting layer as the deterioration preventing layer 24 include organic materials having a nitroxyl radical (NO radical), and 2,2,6,6-tetramethylpiperidine- Examples thereof include N-oxyl (TEMPO) derivatives and polymer materials of the derivatives.

Note that the deterioration preventing layer 24 can be imparted to the electrolyte layer 14 by mixing the material for the deterioration preventing layer with the electrolyte layer 14 without specially forming the deterioration preventing layer 24. Examples of the layer structure in that case are as shown in FIGS. 1C and 1D, for example.
Further, the position at which the deterioration preventing layer 24 is provided is not limited to that shown in the figure, and can be changed as appropriate, and may be in contact with the second electrode layer 15 and on the second substrate 16 side.

  Examples of the method for forming the deterioration preventing layer 24 include a vacuum deposition method, a sputtering method, and an ion rating method. Further, as long as the material of the deterioration preventing layer 24 can be formed by coating, for example, spin coating, casting, micro gravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, etc. And various printing methods such as a slit coating method, a capillary coating method, a spray coating method, a nozzle coating method, a gravure printing method, a screen printing method, a flexographic printing method, an offset printing method, a reverse printing method, and an inkjet printing method. .

  Further, the thickness of the deterioration preventing layer 24 is not particularly limited and can be appropriately changed, but is preferably 0.2 μm to 5.0 μm.

<Third Embodiment>
Next, other embodiments of the electrochromic device according to the present invention will be described. A description of parts common to the above embodiment may be omitted.

  The electrochromic device according to this embodiment has a resin layer 28 on the surface that is in contact with the first substrate 11 and is opposite to the first electrode layer 12. A configuration example of the electrochromic element according to the present embodiment is shown in FIG.

In the present embodiment, after the electrochromic element is processed into a desired shape by thermoforming (see FIG. 1D), the resin layer 28 is formed on the outer surface of the thermoformed electrochromic element. That is, it is formed on the concave surface side of the electrochromic element.
By additionally forming the resin layer 28, the electrochromic element is thickened. Since a desired curved surface can be formed by machining the substrate having a thick film in this way, lens processing (power processing or the like) adapted to user-specific conditions becomes possible. Thereby, an electrochromic light control device such as light control glasses can be easily obtained. According to this method, it is not necessary to prepare a mold or a member for each product shape, and multi-product small-volume production is facilitated.

(Light control glasses)
The light control glasses of the present invention are characterized by using the electrochromic device of the present invention for a lens. Furthermore, it has another member as needed. There is no restriction | limiting in particular as said other member, According to a use, it can select suitably, For example, a spectacles frame, a power supply, a switch, etc. are mentioned.

  A configuration example in one embodiment of the light control glasses according to the present invention is shown in FIG. FIG. 4 is a perspective view showing the light control glasses of the present embodiment. Referring to FIG. 4, the light control glasses 150 include an electrochromic light control device 51, a spectacle frame 52, a switch 53, and a power source 54. The electrochromic light control device 51 is obtained by processing the electrochromic element of the present invention into a desired shape.

  The two electrochromic light control devices 51 are incorporated in the spectacle frame 52. The spectacle frame 52 is provided with a switch 53 and a power source 54. The power supply 54 is electrically connected to the first electrode layer 12 and the second electrode layer 15 through a switch 53 by wiring (not shown).

By switching the switch 53, for example, one of a state in which a positive voltage is applied between the first electrode layer 12 and the second electrode layer 15, a state in which a negative voltage is applied, and a state in which no voltage is applied is selected. Two states can be selected.
As the switch 53, for example, an arbitrary switch such as a slide switch or a push switch can be used. However, it is limited to a switch that can switch at least the three states described above.

As the power source 54, for example, an arbitrary DC power source such as a button battery or a solar battery can be used. The power source 54 can apply a voltage of about plus or minus several volts between the first electrode and the second electrode.
For example, by applying a positive voltage between the first electrode layer 12 and the second electrode layer 15, the two electrochromic light control devices 51 are colored in a predetermined color. Further, by applying a negative voltage between the first electrode layer 12 and the second electrode layer 15, the two electrochromic light control devices 51 are decolored and become transparent.

  However, depending on the characteristics of the material used for the electrochromic layer, when a negative voltage is applied between the first electrode and the second electrode, the color is developed, and when the positive voltage is applied, the color is erased and becomes transparent. There is also. Note that once the color is developed, the color development continues even if no voltage is applied between the first electrode and the second electrode.

  In addition, the electrochromic element of this invention is used suitably for an electrochromic light control apparatus, for example, an anti-glare mirror, light control glass, etc. as uses other than light control glasses. As described above, among these, electrochromic light control glasses are preferable.

(Method for manufacturing electrochromic device)
An electrochromic device manufacturing method according to the present invention includes a step of forming a first electrode layer on a first substrate, a step of forming an electrochromic layer on the first electrode layer, and a second step. A step of forming a second electrode layer on the substrate, a first substrate on which the electrochromic layer is formed, and a second substrate on which the second electrode layer is formed, the first electrode layer and A step of facing the second electrode layer so as to sandwich the electrode layer, and a step of bonding through the electrolyte layer; and a step of processing the bonded first substrate and the second substrate into a three-dimensional curved surface shape. The three-dimensional curved surface shape is a shape in which the first substrate has a convex shape in an inward direction when a region sandwiched between the first substrate and the second substrate is defined as an inner side. The thickness of the substrate is thinner than that of the second substrate. .

Hereinafter, an embodiment of a method for manufacturing an electrochromic device according to the present invention will be described. FIG. 5 shows a manufacturing flowchart of the method for manufacturing the electrochromic device according to the present embodiment. For details, see also the description of each configuration above.
Note that the electrochromic device shown in FIG. 1 is manufactured by the method for manufacturing an electrochromic device according to the present embodiment.

  First, the first substrate 11 is cut into a desired shape (step S1). A first electrode layer 12 is formed on the cut first substrate 11 (step S2). An electrochromic layer 13 is formed on the first electrode layer 12 (step S3). Further, an insulating layer 17 is formed thereon (step S4). Further, an electrolyte solution is applied on the first substrate 11 (step S5). On the other hand, the second substrate 16 is cut into a desired shape (step S6). The second electrode layer 15 is formed on the cut second substrate 16 (step S7).

  Next, the first substrate 11 and the second substrate 16 are bonded together (step S8). The electrolyte solution is cured by, for example, UV to form the electrolyte layer 14 (step S9). A protective layer is formed so as to cover the side surface and / or top surface of the element (step S10). And thermoforming is performed and an electrochromic element is produced (step S11).

  The present invention may further include a step of forming a deterioration preventing layer 24 that is in contact with the second electrode layer 15 and that performs an electrochemical reaction opposite to the oxidation-reduction reaction of the electrochromic layer 13. In the step of forming the deterioration preventing layer 24, after the second electrode layer 15 is formed on the cut second substrate 16 (step S7), the first substrate 11 and the second substrate 16 are bonded together (step S8). ) It may be performed before the process.

  Further, in the present invention, after the step of processing into the three-dimensional curved surface shape, the step of forming the resin layer 28 on the surface that is in contact with the first substrate 11 and opposite to the first electrode layer 11 is performed. You may have. In this case, the resin layer 28 is formed to thicken the electrochromic element, and the thickened electrochromic element can be cut to form a desired curved surface shape.

  Since a desired curved surface can be formed by machining the substrate having a thick film in this way, lens processing (power processing or the like) adapted to user-specific conditions becomes possible. Thereby, an electrochromic light control device such as light control glasses can be easily obtained. According to this method, it is not necessary to prepare a mold or a member for each product shape, and multi-product small-volume production is facilitated.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example.

Example 1
In Example 1, an electrochromic device was fabricated according to the flow diagram shown in FIG.

<External cut of first substrate to insulating layer formation>
First, a substrate obtained by cutting a polycarbonate substrate having a thickness of 0.3 mm (trade name: NF-2000, manufactured by Mitsubishi Gas Chemical Company) into an elliptical shape having a major axis of 80 mm and a minor axis of 55 mm was prepared as the first substrate 11 (FIG. 5). Step S1 in the middle, the following steps are shown in FIG. Next, an ITO film as a transparent conductive film was formed on this substrate by sputtering to form a first electrode layer 12 having a thickness of about 100 nm (S2). Next, a titanium oxide nanoparticle dispersion (trade name: SP210, manufactured by Showa Titanium Co., Ltd., average particle size: about 20 nm) is applied to the surface of the ITO film by a spin coating method and annealed at 60 ° C. for 15 minutes. Thus, a nanostructured semiconductor material composed of a titanium oxide particle film having a thickness of about 1.0 μm was formed.
Subsequently, as an electrochromic compound, a 2,2,3,3-tetrafluoropropanol solution containing 1.5 wt% of the compound represented by the following structural formula (1) was applied by a spin coating method, followed by 10 at 60 ° C. An electrochromic layer 13 was formed by supporting (adsorbing) the titanium oxide particle film by performing an annealing treatment for a minute (S3).

Subsequently, a SiO ₂ fine particle dispersion liquid (silica solid content concentration 24.8 mass%, polyvinyl alcohol 1.2 mass%, and water 74 mass%) having an average primary particle diameter of 20 nm is spin-coated on the electrochromic layer 13. Then, an insulating inorganic fine particle layer (insulating layer 17) was formed (S4). The thickness of the formed insulating inorganic fine particle layer was about 2 μm.

<External cut of second substrate, formation of second electrode layer>
A substrate obtained by cutting a polycarbonate substrate having a thickness of 0.5 mm (trade name: IMR-05, manufactured by Mitsubishi Gas Chemical Company) into the same shape as the first substrate 11 was prepared as the second substrate 16 (S6). On this substrate, an ITO film was formed to a thickness of about 100 nm by sputtering to form a second electrode layer 15 (S7).

<Formation and bonding of electrolyte layer>
Subsequently, polyethylene diacrylate, a photoinitiator (IRG184, manufactured by BASF), and an electrolyte (1-ethyl-3-methylimidazolium salt) are mass ratio (100: 5) on the surface of the insulating inorganic fine particle layer. : 40) is applied onto the first substrate 11 (S5), bonded to the surface of the second electrode layer 15 of the second substrate 16 (S8), and UV-cured to form the electrolyte layer 14. (S9).

<Formation of protective layer>
Next, an ultraviolet curable adhesive (trade name: KARAYADR604, manufactured by Nippon Kayaku Co., Ltd.) is dropped on the side surface of the bonded substrate and cured by ultraviolet light irradiation to form a protective layer having a thickness of about 3 μm. (S10). Thus, an electrochromic element before thermoforming as shown in FIG. 1C was produced.

<Thermoforming>
The produced electrochromic element was sandwiched between a convex mold and a concave mold having a curvature of about 90 mm while being heated at 135 ° C. to produce an electrochromic element having a three-dimensional spherical surface as shown in FIG. S11). At this time, the length of the long axis of the convex spherical surface was 81 mm. The curvature radius was 87.5 mm.

<Color generation / erasing drive>
Next, the color development / erasure of the electrochromic element was confirmed. Specifically, the end portion of the first substrate 11 and a part of the end portion of the second substrate 16 are peeled to form the contact portion of the first electrode layer 12 and the contact portion of the second electrode layer 15. When a voltage of −3.5 V is applied for 3 seconds between the first electrode layer 12 and the second electrode layer 15 so that the first electrode layer 12 becomes a negative electrode, an electrochromic element is obtained. Was confirmed to develop a magenta color derived from the electrochromic compound. Further, when a voltage of +3.5 V is applied between the first electrode layer 12 and the lead-out portion of the second electrode layer 15 for 2 seconds, the electrochromic dye disappears and the electrochromic element becomes transparent. It was confirmed that

(Example 2)
Example 2 is an example of an electrochromic element when the deterioration preventing layer 24 is formed, and the electrochromic element shown in FIG. 2 was produced. Thereafter, fabrication was performed in the same manner as in Example 1 except for the formation of the deterioration preventing layer 24.

<Cut of second substrate-formation of deterioration preventing layer>
A substrate obtained by cutting a polycarbonate substrate having a thickness of 0.5 mm (trade name: IMR-05, manufactured by Mitsubishi Gas Chemical Company) into the same shape as the first substrate 11 was prepared as the second substrate 16. On this substrate, an ITO film was formed to a thickness of about 100 nm by sputtering in the same manner as in Example 1 to form the second electrode layer 15.
Next, an ATO particle dispersion (ATO average particle size: 20 nm / 2,2,3,3-tetrafluoropropanol in a 6 wt% solution with a urethane binder HW140SF (manufactured by DIC) at 6 wt. %) Was applied by spin coating and annealed at 60 ° C. for 15 minutes to form a deterioration preventing layer 24 made of an ATO particle film having a thickness of about 1.0 μm.
Thereafter, similarly to Example 1, an electrochromic element was produced through the formation of the electrolyte layer and the thermoforming process.

<Color generation / erasing drive>
The electrochromic element was confirmed for color development. Specifically, the end portion of the first substrate 11 and a part of the end portion of the second substrate 16 are peeled to form the contact portion of the first electrode layer 12 and the contact portion of the second electrode layer 15. Then, when a voltage of −3.0 V was applied between the first electrode layer 12 and the second electrode layer 15 so that the first electrode layer 12 became a negative pole for 3 seconds, an electrochromic element was obtained. Was confirmed to develop a magenta color derived from the electrochromic compound. Further, when a voltage of +3.0 V is applied between the first electrode layer 12 and the lead-out portion of the second electrode layer 15 for 2 seconds, the electrochromic dye disappears and the electrochromic element becomes transparent. It was confirmed that By forming the deterioration preventing layer 24, low voltage driving is possible.

(Example 3)
Example 3 is an example in which the resin layer 28 is formed on the concave surface of the electrochromic element of Example 1 by injection molding.

<Injection molding>
The convex side of the electrochromic element of Example 1 that has been bent is set in the center of a concave mold of an injection molding machine that includes a mold having a curved surface with a curvature radius of about 90 mm. Next, the concave mold and the convex mold were overlapped to close the mold, and the resin layer 28 was injection molded using a resin material using a polycarbonate resin as a resin for thickening the film (see FIG. 3).

<Color generation / erasing drive>
The electrochromic element was confirmed for color development. Specifically, a hole reaching each of the first and second electrode layers was formed from the surface of the element, and a conductive paste was poured therein to form a contact portion. When a voltage of −3.5 V was applied between the first electrode layer 12 and the second electrode layer 15 for 3 seconds so that the first electrode layer 12 became a negative pole, the electrochromic element was electroelectronized. It was confirmed that the magenta color originated from the chromic compound. Further, when a voltage of +3.5 V is applied between the first electrode layer 12 and the lead-out portion of the second electrode layer 15 for 2 seconds, the electrochromic dye disappears and the electrochromic element becomes transparent. It was confirmed that

(Comparative Example 1)
The electrochromic element of Comparative Example 1 was manufactured in the same manner as Example 1 except that 0.5 mm thick substrates were used as the first substrate 11 and the second substrate 16. That is, the first substrate 11 and the second substrate 16 have the same thickness.

<Color generation / erasing drive>
In the electrochromic element of the comparative example, cracks occurred in the electrode film during thermoforming, resulting in poor appearance. Similarly to the elements of Examples 1 and 2, contact portions of the electrode layers were respectively formed, and when a voltage of +3.5 V was applied for 3 seconds so that the first electrode layer 12 became a negative pole, the resistance value of the electrode layers was As a result, the color did not develop as much as the devices of Examples 1 and 2. Further, when a voltage of −3.5 V was applied between the first electrode layer 12 and the lead portion of the second electrode layer 15 for 2 seconds, the color was not sufficiently erased.

DESCRIPTION OF SYMBOLS 11 1st board | substrate 12 1st electrode layer 13 Electrochromic layer 14 Electrolyte layer 15 2nd electrode layer 16 2nd board | substrate 17 Insulating layer 21, 31 1st board | substrate side 22, 32 2nd board | substrate side 24 Deterioration Prevention layer 28 Resin material part 51 Electrochromic light control device 52 Eyeglass frame 53 Switch 54 Power supply 150 Electrochromic light control glasses

Japanese Patent No. 4105537 JP 2014-112183 A

Claims (7)

At least a first substrate, a first electrode layer formed on the first substrate, an electrochromic layer formed on the first electrode layer, facing the first substrate, and A second substrate disposed on the first electrode layer side, a second electrode layer formed on a surface of the second substrate on the first substrate side, and the first electrode layer, An electrochromic device having an electrolyte layer formed between the second electrode layers,
The electrochromic element has a three-dimensional curved surface shape, and the three-dimensional curved surface shape is a shape in which the first substrate is convex in the direction of the first electrode layer,
The electrochromic element, wherein the first substrate is thinner than the second substrate.   2. The electrochromic device according to claim 1, further comprising a deterioration preventing layer that is in contact with the second electrode layer and that performs an electrochemical reaction opposite to a redox reaction of the electrochromic layer.   The electrochromic device according to claim 1, further comprising a resin layer in contact with the first substrate and on a surface opposite to the first electrode layer.   Light control glasses comprising the electrochromic device according to claim 1 as a lens. Forming a first electrode layer on a first substrate;
Forming an electrochromic layer on the first electrode layer;
Forming a second electrode layer on a second substrate;
The first substrate on which the electrochromic layer is formed and the second substrate on which the second electrode layer is formed are opposed to each other so as to sandwich the first electrode layer and the second electrode layer. A step of bonding through the layers;
Processing the bonded first substrate and second substrate into a three-dimensional curved surface shape,
The three-dimensional curved surface shape is a shape in which the first substrate is convex in the direction of the first electrode layer,
The method of manufacturing an electrochromic device, wherein the thickness of the first substrate is thinner than that of the second substrate.   The electrochromic device according to claim 5, further comprising a step of forming a deterioration preventing layer that is in contact with the second electrode layer and performs an electrochemical reaction opposite to a redox reaction of the electrochromic layer. Manufacturing method. The method of forming a resin layer on a surface that is in contact with the first substrate and opposite to the first electrode layer after the step of processing into the three-dimensional curved surface shape. The method for producing an electrochromic device according to 5 or 6.