JP7565003B2 - Method for manufacturing electrochromic device and electrochromic element - Google Patents

Description

The present invention relates to a method for manufacturing an electrochromic device and to an electrochromic element.

For example, Patent Documents 1 and 2 disclose electrochromic technology that combines an electrochromic element with an optical lens. An electrochromic element is a material that utilizes the phenomenon (electrochromism) in which a reversible oxidation-reduction reaction occurs when a voltage is applied, causing a reversible change in color.

Here, an example of the application of the electrochromic technology described above to healthcare applications is photochromic glasses. Photochromic glasses have an electrochromic element on the surface of the lens or inside it. In this case, it is possible to freely control the transmittance of the photochromic glasses by applying an electrical signal to the electrochromic element.

However, electrochromic technology requires stable electrical connections of electrochromic elements to power sources and drive circuits.

An object of the present invention is to provide a method for manufacturing an electrochromic device that can stabilize the electrical connection to a power source and a drive circuit , and an electrochromic element.

In order to achieve this object, the present invention provides a method for manufacturing an electrochromic device comprising: an intermediate portion including an electrochromic layer; a pair of electrode portions arranged adjacent to both sides of the intermediate portion in the thickness direction of the electrochromic layer; a pair of supports arranged on both sides of the pair of electrode portions in the thickness direction of the electrochromic layer; a protective portion provided in contact with the electrochromic layer and the electrode portions and protecting the side portions of the electrochromic layer; and a pair of electrode lead-out portions electrically connected one by one to the pair of electrode portions, wherein the electrode lead-out portions are exposed in a planar manner through a notch in the support, and the notch is located outside the electrochromic layer in the planar direction of the electrochromic layer, and the electrode lead-out portions are configured to extend in a planar manner along the outer surface of the support by removing a portion of the support surrounded by the processing line and the notch when the notch intersects with a processing line for processing the electrochromic device to a predetermined contour.

According to the present invention, it is possible to realize a manufacturing method for an electrochromic device and an electrochromic element that can stabilize the electrical connection to the power source and the drive circuit.

FIG. 1 is a plan view of a photochromic lens unit according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line F2-F2 in FIG. FIG. 1 is an exploded perspective view of an electrochromic element according to an embodiment. 1A to 1E are diagrams showing a manufacturing method of an electrochromic device (photochromic lens unit) according to one embodiment, in which (a) is a diagram showing a preparation process, (b) is a diagram showing a thermoforming process, (c) is a diagram showing a bonding process, (d) is a diagram showing a processing process, and (e) is a diagram showing a finished product. FIG. 13 is a plan view of a photochromic lens unit having another configuration according to an embodiment. FIG. 4 is a cross-sectional view of an electrochromic element according to a first modified example of the present invention. FIG. 11 is a cross-sectional view of an electrochromic element according to a second modified example of the present invention. FIG. 11 is a cross-sectional view of an electrochromic element according to a third modified example of the present invention. 9 is a cross-sectional view of the electrochromic element of FIG. 8 after removal of the support.

"One embodiment"
Fig. 1 is a configuration diagram of a photochromic lens unit 1 (electrochromic device) according to one embodiment. As shown in Fig. 1, the photochromic lens unit 1 has a photochromic lens body 2 and a pair of electrode lead-out parts (a first electrode lead-out part 3 and a second electrode lead-out part 4). The photochromic lens body 2 is provided between the electrode lead-out parts 3 and 4, and is configured to be able to change the light transmittance.

In the example of FIG. 1, the photochromic lens body 2 has an outline with both upper ends protruding outward, and the electrode extraction parts 3, 4 extend in a planar manner from each of these protruding parts. Note that the pair of protruding parts may be, for example, a part connected to the temples of the eyeglass frame and a part connected to the bridge.

Figure 2 is a cross-sectional view of an electrochromic element 11, which is a main component of the photochromic lens unit 1 (photochromic lens body 2) as an electrochromic device. The electrochromic element 11 is a substance that utilizes the phenomenon (electrochromism) in which a reversible oxidation-reduction reaction occurs and the color changes reversibly when a voltage is applied. The electrochromic element 11 (photochromic lens body 2) has an intermediate portion 5, an adhesive layer 6, a pair of electrode portions (first electrode portion 7, second electrode portion 8), and a pair of supports (first support 9, second support 10).

The electrode sections 7, 8 are arranged adjacent to both sides of the intermediate section 5 described below. The supports 9, 10 have outer surfaces 9a, 10a and inner surfaces 9b, 10b, and are arranged adjacent to both sides of the electrode sections 7, 8. In this case, the inner surfaces 9b, 10b of the supports 9, 10 are adjacent to the electrode sections 7, 8. In addition, the electrode extraction sections 3, 4 described above have parts of the electrode sections 7, 8 exposed to the outside in a planar shape. The electrode extraction sections 3, 4 are electrically connected to the electrode sections 7, 8 one by one.

Furthermore, one electrode lead-out portion (e.g., first electrode lead-out portion 3) is exposed to the outside through a first penetration structure S1 (a cut portion (slit) described later). The other electrode lead-out portion (e.g., second electrode lead-out portion 4) is exposed to the outside through a second penetration structure S2 (a cut portion (slit) described later). In the example of FIG. 2, both electrode lead-out portions 3 and 4 are exposed to the outside through one of the supports (i.e., second support 10).

The first penetration structure S1 extends from the outer surface 10a of the second support 10 through the inner surface 10b. The first penetration structure S1 reaches one electrode portion (e.g., the first electrode portion 7) while avoiding the other electrode portion (e.g., the second electrode portion 8). In this case, a part of the second support 10 is removed by the first penetration structure S1. As a result, a part of the first electrode portion 7 is exposed to the outside and extends in a planar shape. Thus, the first electrode extraction portion 3 is electrically connected to the first electrode portion 7.

The second penetration structure S2 extends from the outer surface 10a of the second support 10 through the inner surface 10b. The second penetration structure S2 avoids one electrode portion (e.g., the first electrode portion 7) and reaches the other electrode portion (e.g., the second electrode portion 8). In this case, a part of the second support 10 is removed by the second penetration structure S2. As a result, a part of the second electrode portion 8 is exposed to the outside and extends in a planar shape. Thus, the second electrode extraction portion 4 is electrically connected to the second electrode portion 8.

At this point, a voltage is applied between the electrode sections 7 and 8 via the electrode leads 3 and 4. This causes a reversible oxidation-reduction reaction in the electrochromic element 11. At this time, the color of the photochromic lens body 2 (in other words, the light transmittance) changes reversibly. This makes it possible to cause the photochromic lens body 2 to develop a color according to, for example, the user's sense or purpose of use, or the environment in which the photochromic lens unit 1 is used.

The intermediate portion 5 includes, for example, an electrochromic layer 5a, an electrolyte layer 5b, and a deterioration prevention layer 5c.
"Electrochromic layer 5a of middle portion 5"
The electrochromic layer 5a contains an electrochromic material and further contains other components as necessary. As the electrochromic material, both an inorganic electrochromic compound and an organic electrochromic compound can be used. In addition, as the electrochromic material, a conductive polymer known to exhibit the above-mentioned electrochromism may be used.

Examples of inorganic electrochromic compounds include tungsten oxide, molybdenum oxide, iridium oxide, and titanium oxide. On the other hand, examples of organic electrochromic compounds include viologen, rare earth phthalocyanine, and styryl. Examples of conductive polymers include polypyrrole, polythiophene, polyaniline, and derivatives thereof.

The electrochromic layer 5a is preferably constructed such that conductive or semiconductive fine particles carry an organic electrochromic compound. Specifically, fine particles with a particle size of about 5 nm to 50 nm are sintered onto the electrode surface, and an organic electrochromic compound having a polar group such as phosphonic acid, a carboxyl group, or a silanol group is adsorbed onto the surface of the fine particles.

This type of structure utilizes the large surface effect of the fine particles to efficiently inject electrons into the organic electrochromic compound, enabling faster response than conventional electrochromic display elements. Furthermore, the use of fine particles makes it possible to form a transparent film as the display layer, thereby enabling the electrochromic dye to have a high color density. In addition, multiple types of organic electrochromic compounds can also be supported on conductive or semiconducting fine particles.

Specific examples of the electrochromic materials mentioned above include polymer-based and dye-based electrochromic compounds, azobenzene-based, anthraquinone-based, diarylethene-based, dihydroprene-based, dipyridine-based, styryl-based, styrylspiropyran-based, spirooxazine-based, spirothiopyran-based, thioindigo-based, tetrathiafulvalene-based, terephthalic acid-based, triphenylmethane-based, triphenylamine-based, naphthopyran-based, viologen-based, pyrazoline-based, phenazine-based, phenylenediamine-based, phenoxazine-based, phenothiazine-based, phthalocyanine-based, fluoran-based, fulgide-based, benzopyran-based, and metallocene-based low molecular weight organic electrochromic compounds, and conductive polymer compounds such as polyaniline and polythiophene.

These electrochromic materials may be used alone or in combination of two or more. Among these, viologen compounds or dipyridine compounds are preferred because they have a low color development/discoloration potential and exhibit good color values. Examples of viologen compounds include those described in Japanese Patent No. 3955641 and Japanese Patent Application Publication No. 2007-171781. Examples of dipyridine compounds include those described in Japanese Patent Application Publication No. 2007-171781 and Japanese Patent Application Publication No. 2008-116718.

Among these, the dipyridine compounds represented by the following general formula (1) are preferred because they exhibit good color values when developed.

In the above general formula (1), R1 and R2 each independently represent an alkyl group having 1 to 8 carbon atoms, or an aryl group, which may have a substituent, and at least one of R1 and R2 has a substituent selected from COOH, PO(OH) ₂ , and Si(OC _k H _2k+1 ) ₃ (where k is 1 to 20).

In the above general formula (1), X represents a monovalent anion, and is not particularly limited as long as it stably pairs with the cation moiety, but examples thereof include Br ion (Br-), Cl ion (Cl-), _ClO4 ion ( _ClO4- ), _PF6 ion ( _PF6- ), _BF4 ion ( _BF4- ), etc. Note that n, m, and l represent 0, 1, or 2. Furthermore, A, B, and C each independently represent an alkyl group, aryl group, or heterocyclic group having 1 to 20 carbon atoms, which may have a substituent.

In addition, inorganic electrochromic compounds such as titanium oxide, vanadium oxide, tungsten oxide, indium oxide, iridium oxide, nickel oxide, and Prussian blue can be used as electrochromic compounds of metal complexes and metal oxides. There are no particular limitations on the conductive or semiconductive fine particles that support the electrochromic compounds described above, and they can be appropriately selected depending on the purpose, but metal oxides are preferred.

The above-mentioned metal oxide materials include metal oxides whose main components are titanium oxide, zinc oxide, tin oxide, zirconium oxide, cerium oxide, yttrium oxide, boron oxide, magnesium oxide, strontium titanate, potassium titanate, barium titanate, calcium titanate, calcium oxide, ferrite, hafnium oxide, tungsten oxide, iron oxide, copper oxide, nickel oxide, cobalt oxide, barium oxide, strontium oxide, vanadium oxide, aluminosilicate, calcium phosphate, aluminosilicate, etc.

These metal oxide materials may be used alone or in combination of two or more. Furthermore, among these, in consideration of electrical properties such as electrical conductivity and physical properties such as optical properties, when one selected from titanium oxide, zinc oxide, tin oxide, zirconium oxide, iron oxide, magnesium oxide, indium oxide, and tungsten oxide or a mixture thereof is used, a color display with an excellent response speed for color development and fading is possible. In particular, when titanium oxide is used, a color display with an even more excellent response speed for color development and fading is possible.

The shape of the conductive or semiconductive fine particles is not particularly limited, but a shape with a large surface area per unit volume (hereinafter referred to as specific surface area) is used in order to efficiently support the electrochromic compound. For example, when the fine particles are an aggregate of nanoparticles, they have a large specific surface area, so that the electrochromic compound is supported more efficiently and the display contrast ratio of color development and fading is excellent.

The thickness of the electrochromic layer 5a is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 0.2 μm to 5.0 μm. In this case, if the thickness is less than 0.2 μm, it may be difficult to obtain a sufficient color density, and if it exceeds 5.0 μm, the manufacturing cost may increase and visibility may be easily reduced due to coloring. In addition, the electrochromic layer 5a and the conductive or semiconductive fine particle layer can be formed by vacuum film formation, but from the viewpoint of productivity, it is preferable to apply the layer as a particle dispersion paste.

"Electrolyte layer 5b of intermediate portion 5"
The electrolyte layer 5b is preferably a solid electrolyte layer, but is not limited thereto and may be a semi-solid or liquid electrolyte layer. In the case of a solid electrolyte layer, it is formed as a film in which an electrolyte is held in a photo- or thermosetting resin, for example.

The electrolyte layer 5b is preferably mixed with inorganic fine particles that control the thickness of the electrolyte layer 5b. If the electrolyte layer 5b is too thin, the possibility of leakage increases, and if it is too thick, the reaction rate slows down. For this reason, the thickness of the electrolyte layer 5b is preferably 5 μm to 200 μm, and more preferably 20 μm to 150 μm.

The electrolyte layer 5b is preferably formed by coating a solution of inorganic fine particles, a curable resin, and an electrolyte on the electrochromic layer 5a, and then curing the solution with light or heat to form a film, but other methods are also acceptable. For example, a porous inorganic fine particle layer may be formed in advance, and then a solution of a curable resin and an electrolyte may be coated so as to penetrate the inorganic fine particle layer, and then cured with light or heat to form a film. Furthermore, when the electrochromic layer 5a is a layer in which an electrochromic compound is supported on conductive or semiconducting nanoparticles, a solution of a curable resin and an electrolyte may be coated so as to penetrate the electrochromic layer 5a, and then cured with light or heat to form a film.

The electrolyte may be a liquid electrolyte such as an ionic liquid, or a solution in which a solid electrolyte is dissolved in a solvent. The electrolyte may be, for example, an inorganic ion salt such as an alkali metal salt or an alkaline earth metal salt, a quaternary ammonium salt, or an acid or alkali supporting salt. 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 , etc.

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

The above-mentioned curable resins include, for example, general materials such as photocurable resins and thermosetting resins, such as acrylic resin, urethane resin, epoxy resin, vinyl chloride resin, ethylene resin, melamine resin, and phenol resin, but materials with high compatibility with the electrolyte are preferred. As such a structure, derivatives of ethylene glycol, such as polyethylene glycol and polypropylene glycol, are preferred. In addition, it is preferable to use a photocurable resin as the curable resin. This is because elements can be manufactured at a lower temperature and in a shorter time than methods of forming a thin film by thermal polymerization or evaporating a solvent.

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

The inorganic fine particles mentioned above are not particularly limited as long as they are materials capable of forming a porous layer and retaining the electrolyte and cured resin, but from the viewpoints of the stability and visibility of the electrochromic reaction, materials with high insulating properties, transparency, and durability are preferred. Specific examples of materials include oxides or sulfides of silicon, aluminum, titanium, zinc, tin, etc., or mixtures thereof.

The size (average particle size) of the inorganic fine particles described above is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 10 nm to 10 μm, and more preferably 10 nm to 100 nm.

"Deterioration prevention layer 5c of intermediate portion 5"
The role of the degradation prevention layer 5c is to undergo a reverse reaction with the electrochromic layer 5a, balance the charge, and prevent the second electrode section 8 from corroding or deteriorating due to an irreversible oxidation-reduction reaction. As a result, the repeated use stability of the above-mentioned photochromic lens unit 1 (electrochromic device) is improved. Note that the reverse reaction includes not only the case where the degradation prevention layer 5c undergoes oxidation-reduction, but also the case where it acts as a capacitor.

The material of the deterioration prevention layer 5c is not particularly limited as long as it is a material that plays a role in preventing corrosion of the electrode parts 7 and 8 due to irreversible oxidation-reduction reactions, and is appropriately selected according to the purpose. For example, antimony tin oxide, nickel oxide, titanium oxide, zinc oxide, tin oxide, or conductive or semiconductive metal oxides containing a plurality of these can be used as the material of the deterioration prevention layer 5c. Furthermore, if coloring of the deterioration prevention layer 5c is not an issue, the same electrochromic material as described above can be used.

Among these, when manufacturing a photochromic lens unit 1 (electrochromic device) as an optical element such as a lens that requires transparency, it is preferable to use a highly transparent material for the deterioration prevention layer 5c. As such a material, it is preferable to use n-type semiconducting oxide fine particles (n-type semiconducting metal oxide). As the n-type semiconducting metal oxide, titanium oxide, tin oxide, zinc oxide, or compound particles containing a plurality of these, or a mixture, can be used, each of which is made up of particles with a primary particle diameter of 100 nm or less.

Furthermore, when the intermediate portion 5 includes the deterioration prevention layer 5c, it is preferable that the electrochromic layer 5a is made of a material that changes color by an oxidation reaction. As a result, when the electrochromic layer 5a undergoes an oxidation reaction, the n-type semiconducting metal oxide is easily reduced (electron injection), and the driving voltage can be reduced.

In this type of configuration, organic polymer materials are particularly preferred electrochromic materials. They can be easily formed into films using coating processes, and their molecular structure makes it possible to adjust and control the color. Specific examples of these organic polymer materials are reported in "Chemistry of Materials review 2011.23, 397-415 Navigating the Color Palette of Solution-Processable Electrochromic Polymers (Reynolds)" (Non-Patent Document 1), "Macromolecules 1996.29 7629-7630 (Reynolds)" (Non-Patent Document 2), and "Polymer journal, Vol. 41, No. 7, Electrochromic Organic Metallic Hybrid Polymers" (Non-Patent Document 3).

These organic polymer materials include, for example, poly(3,4-ethylenedioxythiophene)-based materials and complex-forming polymers of bis(terpyridines) and iron ions.

On the other hand, the material of the highly transparent p-type semiconductor layer as the degradation prevention layer 5c is an organic material having a nitroxyl radical (NO radical), such as a derivative of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) or a polymer material of the derivative.

The method of forming the deterioration prevention layer 5c is not particularly limited and can be appropriately selected according to the purpose. For example, vacuum deposition, sputtering, ion plating, etc. can be used. In addition, as long as the material of the deterioration prevention layer 5c can be applied, various printing methods such as spin coating, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, slit coating, capillary coating, spray coating, nozzle coating, gravure printing, screen printing, flexographic printing, offset printing, reverse printing, and inkjet printing can be used. In addition, the deterioration prevention layer 5c is not particularly limited, and the deterioration prevention layer material can be mixed with the electrolyte layer 5b to impart an anti-deterioration function to the electrolyte layer 5b itself.

"Adhesive layer 6"
The adhesive layer 6 is formed so as to physically and chemically protect the side surface of the electrochromic layer 5a. The adhesive layer 6 can be formed, for example, by applying an ultraviolet-curable or thermosetting insulating resin to cover the side surface and/or the top surface, and then curing the resin. Alternatively, the adhesive layer 6 can be formed by patterning an ultraviolet-curable or thermosetting insulating resin in a sheet shape, attaching the resin, and then curing the resin. Alternatively, the adhesive layer 6 can be formed by patterning a pressure-sensitive adhesive in a sheet shape, and then attaching the pressure-sensitive adhesive.

The adhesive layer 6 preferably has a barrier property, but it is more preferable that the adhesive layer be a laminate of a cured resin and an inorganic material. By forming a laminate structure with the inorganic material described above, the barrier property against oxygen and water is improved. Furthermore, forming a resin barrier layer separately from the adhesive layer 6 is also advantageous in terms of improving the barrier property.

The inorganic material is preferably one that is highly insulating, transparent, and durable. Specific examples of the material include oxides, sulfides, and nitrides of silicon, aluminum, titanium, zinc, and tin, as well as mixtures of these. These films can be easily formed by vacuum film-making processes such as sputtering and deposition.

There are no particular limitations on the thickness of the adhesive layer 6 and it can be selected appropriately depending on the purpose, but it is preferable to make it the same thickness as the electrochromic layer 5a, electrolyte layer 5b, and anti-degradation layer 5c described above. The adhesive layer 6 is preferably formed so as to cover the auxiliary electrode layer placed on the periphery of the glasses, and is preferably formed so as to separate the contact layers 7b and 8b described below from the intermediate portion 5 (electrochromic layer 5a, electrolyte layer 5b, anti-degradation layer 5c).

"Pair of electrode portions 7, 8 (first electrode portion 7, second electrode portion 8)"
The first electrode section 7 is configured by laminating a first contact layer 7b on a first electrode layer 7a. The first electrode layer 7a is adjacent to the inner surface 9b of the first support 9, and the first contact layer 7b is adjacent to the inner surface 10b of the second support 10. On the other hand, the second electrode section 8 is configured by laminating a second contact layer 8b on a second electrode layer 8a. The second electrode layer 8a is adjacent to the inner surface 10b of the second support 10, and the second contact layer 8b is adjacent to the inner surface 9b of the first support 9. In this case, both contact layers 7b, 8b are disposed at positions avoiding the above-mentioned intermediate section 5 (electrochromic layer 5a, electrolyte layer 5b, and anti-degradation layer 5c).

The material of the first electrode layer 7a and the second electrode layer 8a is not particularly limited as long as it is transparent and conductive, and can be appropriately selected according to the purpose. For example, tin-doped indium oxide (hereinafter referred to as "ITO"), fluorine-doped tin oxide (hereinafter referred to as "FTO"), antimony-doped tin oxide (hereinafter referred to as "ATO"), etc. can be mentioned. Among these, inorganic materials containing any one 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 are preferable.

In oxide, Sn oxide, and Zn oxide are materials that can be easily formed into a film by sputtering, and also have good transparency and electrical conductivity. Among these, InSnO _, GaZnO, SnO, _In2O3 , ZnO, and InZnO are particularly preferred. Furthermore, the electrode layers 7a and 8a are preferably as low in crystallinity as possible. This is because the electrode layers are easily broken by thermal molding when the crystallinity is high. From this point of view, IZO and AZO, which show high conductivity in an amorphous film, are preferred.

When using these electrode layer 7a, 8a materials, it is preferable to perform heat forming so that the maximum long axis length of the support on the curved surface of the laminate after heat forming is 120% or less of the maximum long axis length of the support on the flat surface of the laminate before heat forming, and it is more preferable to perform heat forming so that it is 103% or less.

Also useful are thin conductive metal films containing transparent silver, gold, copper, aluminum, etc., carbon films such as carbon nanotubes and graphene, and furthermore, network electrodes of conductive metals, conductive carbon, conductive oxides, etc., or composite layers of these. A network electrode is an electrode that has transmittance by forming carbon nanotubes or other highly conductive non-transparent materials into a fine network. Network electrodes are preferable because they are less likely to break during thermal molding.

Moreover, it is more preferable to use a laminated structure of a network electrode and a conductive oxide, or a laminated structure of a conductive metal thin film and a conductive oxide. By using a laminated structure, the electrochromic layer can be made to develop and fade uniformly. The conductive oxide layer can also be formed by coating as a nanoparticle ink. Specifically, a laminated structure of a conductive metal thin film and a conductive oxide is an electrode that combines conductivity and transparency in a thin film laminated structure such as ITO/Ag/ITO.

The thickness of each of the electrode layers 7a, 8a is adjusted so as to obtain the electrical resistance value required for the redox reaction of the electrochromic layer 5a. When ITO vacuum deposition is used as the material for the electrode layers 7a, 8a, the thickness of each of these electrode layers 7a, 8a is preferably 20 nm to 500 nm, more preferably 50 nm to 300 nm.

When applied as a nanoparticle ink, the thickness of the conductive oxide layer is preferably 0.2 μm to 5 μm. In addition, the thickness of the network electrode is preferably 0.2 μm to 5 μm.

Furthermore, when used as a switchable mirror, either of the electrode layers 7a and 8a may have a reflective function. In that case, the material of the electrode layers 7a and 8a may include a metal material. Examples of the metal material include Pt, Ag, Au, Cr, rhodium, Al, alloys of these, and laminated structures of these.

Examples of the method for producing each of the electrode layers 7a and 8a include vacuum deposition, sputtering, and ion plating. In addition, as long as the material for each of the electrode layers 7a and 8a can be applied, examples of the method include various printing methods such as spin coating, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, slit coating, capillary coating, spray coating, nozzle coating, gravure printing, screen printing, flexographic printing, offset printing, reverse printing, and inkjet printing.

The material for the first contact layer 7b and the second contact layer 8b is not particularly limited as long as it is a conductive material, but it is particularly preferable to use a conductive paste in which conductive particles are mixed with a resin. For example, a mixture of silver particles, copper particles, nickel particles, or carbon particles with an epoxy resin, polyester resin, acrylic resin, or silicone resin can be used.

The thickness of the contact layers 7b, 8b is preferably equal to or greater than that of the electrochromic layer 5a and electrolyte layer 5b described above, with a thickness of 5 μm to 200 μm being preferred, and 30 to 100 μm being even more preferred. In FIG. 2, as an example, the thickness of the contact layers 7b, 8b is set to be equal to or greater than that of the intermediate portion 5 (electrochromic layer 5a, electrolyte layer 5b, and anti-degradation layer 5c) described above.

"A pair of supports (first support 9, second support 10)"
The first support 9 and the second support 10 have the function of supporting the above-mentioned intermediate portion 5 (electrochromic layer 5a, electrolyte layer 5b, anti-degradation layer 5c), the first electrode portion 7 (first electrode layer 7a, first contact layer 7b), and the second electrode portion 8 (second electrode layer 8a, second contact layer 8b).

As the supports 9 and 10, any known thermoformable resin material can be used as is, so long as it can support the intermediate portion 5 and the electrode portions 7 and 8. Furthermore, as the supports 9 and 10, resin substrates such as polycarbonate resin, acrylic resin, polyethylene resin, polyvinyl chloride resin, polyester resin, epoxy resin, melamine resin, phenolic resin, polyurethane resin, polyimide resin, etc. may also be used.

When the photochromic lens unit 1 (electrochromic device) is a reflective display device that is viewed from the second electrode portion 8 side, the transparency of either the supports 9, 10 is not required. The surfaces of the supports 9, 10 may be coated with a transparent insulating layer, an anti-reflection layer, or the like to improve water vapor barrier properties, gas barrier properties, and visibility. Furthermore, the thickness of the supports 9, 10 is preferably 0.2 mm to 1.0 mm in order to facilitate thermoforming.

Figures 3 and 4 are schematic diagrams showing a manufacturing method for the photochromic lens unit 1 (electrochromic device). Figure 3 shows the manufacturing method for the electrochromic element 11 up to the stage before thermal molding. Figure 4 shows the manufacturing method from thermal molding to edging. Note that the manufacturing method shown in Figures 3 and 4 is merely one example, and does not limit the technical scope of the present invention.

As shown in FIG. 3, in the manufacturing method of the electrochromic element 11, the above-mentioned first through structure S1 and second through structure S2 are provided in advance on one of the supports (e.g., the second support 10). These through structures S1 and S2 are cut-outs (also called slits) that extend from the outer surface 10a of the second support 10 through the inner surface 10b. The slit-shaped first through structure S1 reaches the first electrode portion 7. On the other hand, the slit-shaped second through structure S2 reaches the second electrode portion 8.

In this manufacturing method, for example, the first electrode portion 7 is laminated on the inner surface 9b of the first support 9. The second electrode portion 8 is laminated on the inner surface 10b of the second support 10. Next, the intermediate portion 5 (electrochromic layer 5a, electrolyte layer 5b, deterioration prevention layer 5c) is interposed between the two electrode portions 7, 8 and hardened, and then the outer periphery is sealed with the adhesive layer 6. Three openings (first opening L1, second opening L2, third opening L3) are formed in the adhesive layer 6 beforehand.

The first opening L1 is disposed opposite the first contact layer 7b of the first electrode portion 7 and has approximately the same contour as the first contact layer 7b. The second opening L2 is disposed opposite the second contact layer 8b of the second electrode portion 8 and has approximately the same contour as the second contact layer 8b. The third opening L3 is disposed opposite the intermediate portion 5 and has approximately the same contour as the intermediate portion 5.

Then, the two supports 9, 10 are bonded together, sandwiching the intermediate portion 5 and the electrode portions 7, 8. This produces an electrochromic element 11 in which the electrochromic layer 5a is encapsulated. Next, the electrochromic element 11 is subjected to thermal molding and edging (see FIG. 4).

In the thermoforming and edging processes, for example, the electrochromic element 11 described above is prepared (FIG. 4(a)). After the electrochromic element 11 is subjected to thermoforming, the thermoformed electrochromic element 11 and the optical lens 12 are bonded together by sheet insert injection (FIG. 4(b)). In this way, the electrochromic device 1 consisting of the electrochromic element 11 and the optical lens 12 is manufactured (FIG. 4(c)).

After this, the electrochromic device 1 is processed. In the processing, a processing line 13 is set to process the electrochromic device 1 into a preset outline (FIG. 4(d)). In this case, the processing line 13 is set so as to intersect with the above-mentioned through structures S1 and S2. Then, an edge processing is performed along the processing line 13 to produce the photochromic lens unit 1.

In this state, the second support 10 is removed from the portions P1 and P2 surrounded by the processing line 13 and the through structures S1 and S2. This results in a pair of electrode lead-out portions 3 and 4 in which parts of the electrode portions 7 and 8 extend planarly along the outer surface 10a of the second support 10 (FIG. 4(e)). The electrode lead-out portions 3 and 4 are exposed to the outside through the second support 10 and are electrically connected to the electrode portions 7 and 8, one by one.

Figure 4(e) shows an example of an enlarged view of the first electrode lead-out portion 3. Due to the edging process along the processing line 13 described above, an outwardly protruding outline remains at both upper ends 1t of the photochromic lens unit 1 (photochromic lens body 2). The electrode lead-out portions 3 and 4 extend in a planar shape along the outer surface of this remaining portion.

"Optical lens 12"
As the material for the optical lens 12, for example, transparent materials such as polycarbonate resin, allyl diglycol carbonate resin, diallyl carbonate resin, diallyl phthalate-based resin, urethane-based resin, thiourethane-based resin, episulfide-based resin, methacrylate-based resin, and cycloolefin-based resin materials are suitably used, but are not limited to these.

The optical lens 12 can be formed by bonding these transparent resins to one of the outer surfaces, melting and then re-hardening them, hardening them by applying light or heat, or bonding them with an optically transparent adhesive. However, the method of bonding the optical lens 12 is not limited to these methods. For example, methods that can be selected include in-mold injection molding, film (sheet) insert injection molding, film (sheet) insert cast molding, and bonding using a transparent optical (optically transparent) adhesive/adhesive film.

By setting the radius of curvature after curing while taking into account deformation due to curing shrinkage, etc., it is possible to adjust the curvature of the entrance surface and/or the exit surface of the optical lens 12, thereby imparting any desired power to the electrochromic device. In addition, after forming the optical lens 12, the desired curved shape can be formed by cutting, making it possible to process the lens (power processing, etc.) according to the specific conditions of the user. In other words, it is no longer necessary to prepare molds and parts for each product shape, making it easier to produce a wide variety of high-precision products in small quantities.

"Effects of one embodiment"
According to this embodiment, in the electrochromic device 1 (photochromic lens unit) consisting of the electrochromic element 11 and the optical lens 12, the portions electrically connected to the power source and drive circuit (i.e., the electrode extraction portions 3, 4) are exposed to the outside while extending in a planar manner, thereby stabilizing the electrical connection of the electrochromic device 1 (electrochromic element 11, photochromic lens unit 1) to the power source and drive circuit.

In other words, by extending the electrode extraction parts 3, 4 in a planar manner, the contact area with the electrode extraction parts 3, 4 can be increased and the contact pressure can be made uniform. As a result, the occurrence of poor electrical contact can be suppressed. In this way, it is possible to realize a highly reliable electrochromic device 1 (electrochromic element 11, photochromic lens unit 1) with excellent electrochromic reaction that can be used stably for a long period of time.

"Another Configuration of One Embodiment"
5 is a diagram showing another arrangement of the electrode lead-out parts 3, 4. The arrangement of the electrode lead-out parts 3, 4 is not limited to the protruding parts at both ends of the upper part of the photochromic lens body 2 (see FIG. 1) described above, and may be any part that allows the electrode lead-out parts 3, 4 to extend in a planar manner.

In FIG. 5, as an example, the electrode lead-out portions 3, 4 are arranged side by side on the upper side of the portion that is to become the photochromic lens body. Therefore, the through structures S1, S2 are set with an outline that surrounds the processing line 13 that extends linearly. In this state, the second support 10 is removed from the portions P1, P2 surrounded by the processing line 13 and the through structures S1, S2. This forms a pair of electrode lead-out portions 3, 4 in which parts of the electrode portions 7, 8 extend planarly along the outer surface 10a of the second support 10.

"First Modified Example"
Fig. 6 is a cross-sectional view of an electrochromic element 11, which is a main component of the electrochromic device 1 (see Fig. 1) according to the first modified example. In this modified example, both of the pair of electrode extraction parts 3, 4 are exposed to the outside via the other support (i.e., the first support 9). Note that in this modified example, the configuration and the effects other than those described below are the same as those of the above-mentioned embodiment, so the description thereof will be omitted.

The first penetration structure S1 extends from the outer surface 9a of the first support 9 through the inner surface 9b. The first penetration structure S1 reaches one electrode portion (e.g., the first electrode portion 7) while avoiding the other electrode portion (e.g., the second electrode portion 8). In this case, a part of the first support 9 is removed by the first penetration structure S1. As a result, a part of the first electrode portion 7 is exposed to the outside and extends in a planar shape. Thus, the first electrode extraction portion 3 is electrically connected to the first electrode portion 7.

The second penetration structure S2 extends from the outer surface 9a of the first support 9 through the inner surface 9b. The second penetration structure S2 avoids one electrode portion (e.g., the first electrode portion 7) and reaches the other electrode portion (e.g., the second electrode portion 8). In this case, a part of the first support 9 is removed by the second penetration structure S2. As a result, a part of the second electrode portion 8 is exposed to the outside and extends in a planar shape. Thus, the second electrode extraction portion 4 is electrically connected to the second electrode portion 8.

"Second Modification"
7 is a cross-sectional view of an electrochromic element 11, which is a main component of the electrochromic device 1 (see FIG. 1) according to a second modified example. In this modified example, a pair of electrode extraction parts 3 and 4 are exposed to the outside via both supports (i.e., the first support 9 and the second support 10).

In FIG. 7, as an example, the first penetration structure S1 extends from the outer surface 9a of the other support (i.e., the first support 9) through the inner surface 9b. The second penetration structure S2 extends from the outer surface 10a of one support (i.e., the second support 10) through the inner surface 10b. Note that in this modified example, the configuration and effects other than those described below are the same as those of the above-mentioned embodiment, so a description thereof will be omitted.

The first penetration structure S1 reaches one electrode portion (e.g., the first electrode portion 7) while avoiding the other electrode portion (e.g., the second electrode portion 8). In this case, a part of the first support 9 is removed by the first penetration structure S1. As a result, a part of the first electrode portion 7 is exposed to the outside and extends in a planar shape. Thus, the first electrode extraction portion 3 is electrically connected to the first electrode portion 7.

The second penetration structure S2 avoids one electrode portion (e.g., the first electrode portion 7) and reaches the other electrode portion (e.g., the second electrode portion 8). In this case, a part of the second support 10 is removed by the second penetration structure S2. As a result, a part of the second electrode portion 8 is exposed to the outside and extends in a planar shape. Thus, the second electrode extraction portion 4 is electrically connected to the second electrode portion 8.

"Third Modification" Figure 8 is a cross-sectional view of an electrochromic element 11, which is a main component of an electrochromic device 1 (see Figure 1) according to a third modification. This modification shows the state before the through structures S1 and S2 are formed (i.e., before the second support 10 is removed from the notch). In this case, a planar electrode 8c is added in contact with the second contact layer 8b. The planar electrode 8c is formed by depositing a film at the same time as the first electrode layer 7a, but is not connected to the first electrode layer 7a.

The second electrode layer 8a is formed on the second support 10, and is highly likely to be removed along with the part of the support 10 that is being removed when the support 10 is removed. To avoid this, the notch S2 is provided outside the adhesive layer 6, ensuring that the second contact layer 8b remains even after the support 10 is removed, thereby electrically contacting the second electrode layer 8a via the planar electrode 8c on the first support 9.

Figure 9 is a cross-sectional view of the electrochromic element 11 of Figure 8 after the support is removed. As shown in Figure 9, even if the second electrode layer 8a is removed together with the removed portion of the support 10, the second contact layer 8b can be reliably left behind. This allows electrical contact with the second electrode layer 8a via the planar electrode 8c on the first support 9, and as a result, the electrode portions 7 and 8 can be exposed in a planar manner from the electrode extraction portions 3 and 4.

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In these examples, the case of manufacturing a photochromic lens unit 1 (electrochromic device) shown in Figures 1 to 4 is assumed.

"Forming of the first electrode layer 7a and the electrochromic layer 5a of the first electrode portion 7"
First, an elliptical polycarbonate substrate having a maximum major axis length of 75.5 mm, a maximum minor axis length of 54 mm, and a thickness of 0.3 mm was prepared as the first support 9. Then, an ITO film was formed on the first support 9 by a sputtering method to a thickness of about 100 nm, thereby forming the first electrode layer 7a.

Next, a titanium oxide nanoparticle dispersion (product name: SP210, manufactured by Showa Titanium Co., Ltd., average particle size: 20 nm) was applied to the surface of the ITO film by spin coating, and annealing was performed at 120°C for 15 minutes to form a nanostructured semiconductor material consisting of a titanium oxide particle film with a thickness of approximately 1.0 μm.

Next, a 2,2,3,3-tetrafluoropropanol solution containing 1.5% by mass of an electrochromic compound represented by the following structural formula (A) was applied by spin coating, and then annealed at 120°C for 10 minutes to support (adsorb) the compound on the titanium oxide particle film, forming an electrochromic layer 5a.

Next, a dispersion of SiO2 particles with an average primary particle size of 20 nm (silica solids concentration 24.8% by mass, polyvinyl alcohol 1.2% by mass, and water 74% by mass) was spin-coated onto the electrochromic layer 5a to form an insulating inorganic particle layer with a thickness of 2 μm.

"Formation of second electrode layer 8a of second electrode portion 8"
A polycarbonate substrate having the same shape and thickness as the first support 9 was prepared as the second support 10. Slit-shaped through structures S1, S2 (see FIG. 3) were provided in advance in the second support 10. Then, an ITO film was formed on the second support 10 by a sputtering method to a thickness of about 100 nm, forming the second electrode layer 8a.

"Formation of adhesive layer 6"
Next, an optically transparent adhesive sheet (product name: LA-50, manufactured by Nitto Denko Corporation) was processed into the shape shown in FIG. 3, and then attached to the first support 9 on which the first electrode layer 7a and the electrochromic layer 5a were formed, using a laminating device.

"Formation of contact layers 7b, 8b of electrode portions 7, 8"
Next, a conductive paste (Dotite XA-910, manufactured by Fujikura Chemical Industries, Ltd.) was applied by a dispenser to the positions shown in FIG. 3 on the first support 9 on which the first electrode layer 7a, the electrochromic layer 5a and the adhesive layer 6 had been formed.

"Formation of electrolyte layer 5b and deterioration prevention layer 5c, and bonding of supports 9 and 10"
Next, a solution obtained by mixing polyethylene glycol diacrylate (PEG400DA, manufactured by Nippon Kayaku Co., Ltd.), a photopolymerization initiator (IRG184, manufactured by BASF Co., Ltd.) and an electrolyte (1-ethyl-3-methylimidazolium salt) in a mass ratio of 100:5:40 was applied to the surface of the insulating inorganic fine particle layer on the first support 9 using a dispenser, and the solution was bonded to the second support 10 using a vacuum bonding device and cured with ultraviolet (UV) light to form an electrolyte layer 5b. In addition, a degradation prevention layer 5c was formed on the formed electrolyte layer 5b.
In this manner, the electrochromic element 11 before thermoforming shown in FIGS. 2 and 3 was manufactured.

"3D thermoforming"
The electrochromic element 11 thus produced was sandwiched between a convex mold and a concave mold having a radius of curvature of approximately 130 mm while being heated at 146° C., thereby forming the electrochromic element 11 of Example 1 having a 3D spherical shape (see FIG. 4(b)).

The maximum long axis length of the support on the curved surface of the electrochromic element 11 after heat molding was 76 mm, and the maximum long axis length of the support on the curved surface of the electrochromic element 11 after heat molding was (76 mm/75.5 mm) x 100 = 100.7% of the maximum long axis length of the support on the flat surface of the electrochromic element 11 before heat molding.

"Adhesive formation of optical lens 12"
Polycarbonate resin Iupilon CLS3400 (manufactured by Mitsubishi Engineering Plastics Corporation) was used as the material for the optical lens 12 to be bonded to the electrochromic element 11 after thermoforming, and the electrochromic element 11 was inserted into a mold and integrally molded into a lens shape by injection molding (see FIG. 4(c)). Thus, the electrochromic device 1 consisting of the electrochromic element 11 and the optical lens 12 was formed by sheet insert injection molding.

"Processing of the optical lens 12, the electrochromic device 1, and exposure of the contact portion"
Thereafter, the surface of the optical lens 12 formed by adhering to the electrochromic device 1 was machined to have a curvature. Furthermore, the electrochromic device 1 (electrochromic element 11, optical lens 12) was machined to have an edge shape that fits into an eyeglass frame.

At this time, the electrochromic device 1 is formed into a preset outline along the processing line 13 (see FIG. 4(d)). Then, the second support 10 is removed from the portions P1 and P2 surrounded by the processing line 13 and the first through structure S1 (slit). This results in the formation of a pair of electrode extraction portions 3 and 4 in which parts of the electrode portions 7 and 8 extend planarly along the outer surface 10a of the second support 10.

"Color generation and erasure drive"
The color development and decolorization of the manufactured photochromic lens unit 1 (electrochromic device) was confirmed. Specifically, a voltage was applied between the first electrode portion 7 (first electrode layer 7a) and the second electrode portion 8 (second electrode layer 8a) via the electrode extraction portions 3, 4 that were exposed in a planar shape on the outer surface 10a of the second support 10 by edging. At this time, a voltage of -3.5V was applied for 3 seconds so that the first electrode layer 7a became the negative pole. It was then confirmed that the photochromic lens unit 1 (electrochromic device) stably developed the magenta color derived from the electrochromic compound of the above structural formula (A).

"Shapes of the through structures S1, S2" In the above-described embodiment, the through structures S1, S2 are assumed to be cuts (slits) extending from the outer surface 9a, 10a of the support 9, 10 to the inner surface 9b, 10b, but are not limited to this and may be cuts extending without penetrating (non-penetrating deep grooves with bottoms). Even with non-penetrating cuts, the support 9, 10 can be partially removed at the cut, thereby forming the electrode extraction portions 3, 4 in which part of the electrode portions 7, 8 are exposed in a planar manner.

1...electrochromic device (photochromic lens unit), 2...photochromic lens body, 3...first electrode lead-out portion, 4...second electrode lead-out portion, 5...intermediate portion, 5a...electrochromic layer, 5b...electrolyte layer, 5c...deterioration prevention layer, 6...adhesive layer, 7...first electrode portion, 7a...first electrode layer, 7b...first contact layer, 8...second electrode portion, 8a...second electrode layer, 8b...second contact layer, 9...first support, 10...second support, 11...electrochromic element, S1...first penetration structure, S2...second penetration structure.

JP 2018-132635 A WO 2017/104466 A1

Claims (3)

a middle portion including an electrochromic layer;
A pair of electrode portions arranged adjacent to both sides of the intermediate portion in a thickness direction of the electrochromic layer;
A pair of supports arranged on both sides of the pair of electrode portions in a thickness direction of the electrochromic layer;
a protective portion provided in contact with the electrochromic layer and the electrode portion and protecting a side surface portion of the electrochromic layer;
a pair of electrode lead-out portions electrically connected to the pair of electrode portions,
The electrode extraction portion is exposed in a planar manner through a cut portion of the support,
A method for manufacturing an electrochromic device, the notch portion being located outside the electrochromic layer in a surface direction of the electrochromic layer, comprising the steps of:
A manufacturing method for an electrochromic device in which the electrode extraction portion is configured to extend in a planar manner along the outer surface of the support by removing the support in a portion surrounded by the processing line and the notch when the processing line for processing the electrochromic device into a predetermined contour intersects with the notch . a middle portion including an electrochromic layer;
A pair of electrode portions arranged adjacent to both sides of the intermediate portion in a thickness direction of the electrochromic layer;
A pair of supports arranged on both sides of the pair of electrode portions in a thickness direction of the electrochromic layer;
a protective portion provided in contact with the electrochromic layer and the electrode portion and protecting a side surface portion of the electrochromic layer;
a pair of electrode lead-out portions electrically connected to the pair of electrode portions,
The electrode extraction portion is exposed in a planar manner through a cut portion of the support,
A method for manufacturing an electrochromic device, comprising the steps of:
providing one of the electrode portions on one of the supports;
providing the other electrode portion on the other support;
providing the intermediate portion between the electrode portions;
a step of bonding the two supports together with the intermediate portion therebetween;
providing a pair of electrode extraction portions that are exposed to the outside through both or either of the supports and electrically connected to the pair of electrode portions,
The electrode extraction portion is exposed in a planar manner through a cut portion of the support,
A manufacturing method for an electrochromic device, in which the electrode extraction portion is configured by removing the support in a portion surrounded by the processing line for processing the electrochromic device into a predetermined contour and the notch, thereby extending a portion of the electrode portion in a planar manner along the outer surface of the support . a middle portion including an electrochromic layer;
A pair of electrode portions disposed adjacent to each other on both sides of the intermediate portion;
A pair of supports arranged on both sides of the pair of electrode portions;
a pair of electrode lead-out portions electrically connected to the pair of electrode portions,
A notch portion is formed in the support toward the electrode lead-out portion, the notch portion penetrating or not penetrating the support,
a protective portion provided in contact with the electrochromic layer and the electrode portion to protect a side surface portion of the electrochromic layer;
The notch is an electrochromic element located outside the electrochromic layer in a plane direction of the electrochromic layer.

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