Electrochromic sheet, laminate, lens for eyeglasses, and eyeglasses

Abstract

An electrochromic sheet comprising: a first substrate; a second substrate; an electrochromic element; and a sealing portion, wherein the electrochromic element includes a first transparent electrode, a first auxiliary electrode, a second transparent electrode, a second auxiliary electrode, and an electrochromic layer, the first auxiliary electrode and the second auxiliary electrode are disposed around a colored region, the first auxiliary electrode has a strip-shaped first frame body surrounding a portion of the electrochromic layer and a first extraction portion disposed at one end of the first frame body, the second auxiliary electrode has a strip-shaped second frame body surrounding a portion of the electrochromic layer and a second extraction portion disposed at one end of the second frame body, the first extraction portion and the second extraction portion are spaced apart by more than 0 mm and not more than 10 mm in plan view, and the other end of the first frame body and the other end of the second frame body are spaced apart by more than 0 mm and not more than 20 mm in plan view.

Description

Electrochromic sheet, laminate, eyeglass lens and eyeglasses

[0001] This application claims priority to Japanese Patent Application No. 2024-002464, filed January 11, 2024, the contents of which are incorporated herein by reference.

[0002] Electrochromism is a phenomenon in which an applied voltage causes a redox reaction, resulting in a reversible color change. Electrochromic elements, which utilize this phenomenon and control the color by applying a voltage using electrochromic materials, are known.

[0003] The electrochromic element includes, for example, an electrochromic layer that develops or loses color when a voltage is applied, and transparent electrodes that sandwich the electrochromic layer and are electrically connected to the electrochromic layer (see, for example, Patent Document 1).

[0004] Electrochromic sheets equipped with electrochromic elements are used, for example, as materials for eyewear such as sunglasses and wearable devices such as smart glasses.

[0005] Japanese Patent Application Laid-Open No. 2017-167317

[0006] The transparent electrodes used in the configuration of Patent Document 1 are formed using a material having high electrical conductivity and high visible light transmittance. Known materials for the transparent electrodes include oxides such as ITO (indium tin oxide).

[0007] On the other hand, the above materials have higher electrical resistance than metal materials, so that in an electrochromic layer sandwiched between transparent electrodes made of ITO, there are regions where current easily flows and regions where it does not, and color unevenness tends to occur in the color change (coloring and decoloring) of the electrochromic layer.

[0008] The present invention has been made in view of the above circumstances, and aims to provide an electrochromic sheet capable of coloring and decoloring without delay. It is also an object of the present invention to provide a laminate including such an electrochromic sheet, an eyeglass lens, and eyeglasses including the eyeglass lens.

[0009] To solve the above problem, we investigated a configuration that uses an auxiliary electrode to supplement the conductivity of the transparent electrode. In general, the auxiliary electrode is made of a metal material that has lower electrical resistance than the material of the transparent electrode. By using the auxiliary electrode, the problem of delayed discoloration can be solved.

[0010] On the other hand, in the course of further investigation into the auxiliary electrode, it was found that depending on the shape of the auxiliary electrode formed, the auxiliary electrode may not be able to fully perform the function expected of the auxiliary electrode, resulting in color unevenness. Based on this knowledge, the present invention was completed through extensive investigation.

[0011] In order to solve the above problems, one aspect of the present invention includes the following aspects.

[0012] [1] A liquid crystal display device comprising: a first substrate; a second substrate; an electrochromic element sandwiched between the first substrate and the second substrate; and a sealing portion sandwiched between the first substrate and the second substrate and defining a colored region set between the first substrate and the second substrate, wherein the electrochromic element has a first transparent electrode provided on the first substrate side; a first auxiliary electrode electrically connected to the first transparent electrode; a second transparent electrode provided on the second substrate side; a second auxiliary electrode electrically connected to the second transparent electrode; and an electrochromic layer sandwiched between the first transparent electrode and the second transparent electrode, disposed in the colored region, and colored by application of a voltage; an electrochromic sheet in which the first auxiliary electrode has a band-shaped first frame body surrounding a portion of the electrochromic layer and a first extraction portion provided at one end of the first frame body and protruding from the first frame body to the outside of the colored region, the second auxiliary electrode has a band-shaped second frame body surrounding a portion of the electrochromic layer and a second extraction portion provided at one end of the second frame body and protruding from the second frame body to the outside of the colored region, the first extraction portion and the second extraction portion being spaced apart by more than 0 mm but not more than 10 mm in a planar view, and the other end of the first frame body and the other end of the second frame body being spaced apart by more than 0 mm but not more than 20 mm in a planar view.

[0013] [2] The electrochromic sheet according to [1], wherein the total length of the first frame is more than 50% but less than 200% of the total length of the second frame.

[0014] [3] The electrochromic sheet according to [1] or [2], wherein the electrochromic layer comprises a first electrochromic layer laminated on the first transparent electrode, a second electrochromic layer laminated on the second transparent electrode, and an electrolyte layer filled between the first electrochromic layer and the second electrochromic layer, wherein the first electrochromic layer contains a material that exhibits coloration by an oxidation reaction, and the second electrochromic layer contains a material that exhibits coloration by a reduction reaction.

[0015] [4] A laminate comprising the electrochromic sheet according to any one of [1] to [3] and a lens material on which the electrochromic sheet is laminated.

[0016] [5] An eyeglass lens comprising: an electrochromic section obtained by cutting the electrochromic sheet described in any one of [1] to [3] along the outer peripheries of the first auxiliary electrode and the second auxiliary electrode; and a lens body on which the electrochromic section is laminated, wherein the lens body has protrusions having the same shape as the first extraction section and the second extraction section in a planar view.

[0017] [6] Eyeglasses comprising the eyeglass lens according to [5] and a frame that holds the eyeglass lens, wherein the first extraction portion and the second extraction portion are electrically connected to the frame.

[0018] According to the present invention, it is possible to provide an electrochromic sheet capable of developing and decoloring without delay, and also to provide a laminate including such an electrochromic sheet, an eyeglass lens, and eyeglasses including the eyeglass lens.

[0019] Fig. 1 is a perspective view showing sunglasses (eyeglasses) using an electrochromic sheet according to an embodiment as a material. Fig. 2 is an exploded perspective view of an electrochromic sheet 150. Fig. 3 is a partial cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is a plan view showing an example of an EC sheet 150. Fig. 5 is an explanatory diagram illustrating a method for manufacturing lenses using the EC sheet 150.

[0020] The electrochromic sheet, laminate, eyeglass lens, and eyeglasses according to this embodiment will be described below with reference to Figures 1 to 5. In all of the following drawings, the dimensions and proportions of each component have been appropriately changed to make the drawings easier to understand. In the following description, the term "electrochromic" may be abbreviated as "EC."

[0021] <Eyeglasses> Fig. 1 is a perspective view showing sunglasses (eyeglasses) using the electrochromic sheet (EC sheet) of this embodiment as a material. Sunglasses are an example of eyeglasses.

[0022] In this specification, the term "eyeglasses" refers to any device (eyewear in general) worn on the user's head with lenses positioned in front of the user's eyes. In this definition, "eyeglasses" includes not only regular eyeglasses that correct the user's vision, but also well-known eyewear such as sunglasses and goggles that protect the user's eyes, and smart glasses (wearable devices) that display information on the lenses.

[0023] As shown in FIG. 1 , sunglasses 100 include a pair of lenses 110 (eyeglass lenses) and a frame 120 .

[0024] [Lens] The lens 110 is transparent to visible light and can reversibly develop or decolor by switching the application of voltage. In this specification, the term "lens (eyeglass lens)" includes both lenses having a light-condensing function and lenses having no light-condensing function.

[0025] The lens 110 has an electrochromic portion 111 (EC portion 111) formed from an EC sheet described below, and a lens body 115 on which the EC portion 111 is laminated. When a user wears the sunglasses 100, the lens body 115 is located on the user's side, and the EC portion 111 is located on the side of the lens body 115 opposite the user.

[0026] [Frame] The frame 120 includes a pair of rim portions 121, a bridge portion 122, a pair of temple portions 123, and a pair of nose pad portions 124. The frame 120 is worn on the head of a user. The frame 120 positions the lenses 110 in front of the user's eyes.

[0027] The rim portions 121 are formed in a closed ring shape. The pair of rim portions 121 correspond to the right and left eyes of the user, respectively. The rim portions 121 may be in an open ring shape. Furthermore, the frame 120 may be configured without the rim portions 121.

[0028] The bridge portion 122 connects the pair of rim portions 121. The bridge portion 122 is located in front of the top of the user's nose when the glasses are worn on the user's head.

[0029] The pair of temple portions 123 are connected to the rim portion 121 at positions opposite to the position where the bridge portion 122 is connected. The temple portions 123 are hooked over the user's ears when the glasses are worn on the user's head.

[0030] The temple portion 123 has a switch 125 and a battery 126. The switch 125 is exposed on the outer surface of the temple portion 123. The switch 125 is electrically connected to the lens 110 via a wire. The switch 125 can switch between applying a positive voltage, applying a negative voltage, and not applying a voltage to the lens 110, for example.

[0031] The battery 126 is built into the temple portion 123. The battery 126 is electrically connected to the lens 110 via a wire.

[0032] The nose pads 124 are formed on each rim 121 at positions corresponding to the user's nose. The nose pads 124 come into contact with the user's nose. The nose pads 124 stabilize the wearing state of the sunglasses 100.

[0033] For example, metal materials, resin materials, etc. can be used as the constituent material of the frame 120. The shape of the frame 120 is not limited to the example shown in the figure, as long as it is a shape that can be worn on the user's head.

[0034] <Electrochromic Sheet> Fig. 2 is an exploded perspective view of the electrochromic sheet 150 (EC sheet 150), and Fig. 3 is a partial cross-sectional view taken along line III-III in Fig. 2. The EC sheet 150 is used as a material for eyeglass lenses, which will be described later.

[0035] 2 and 3, the EC sheet 150 includes a first substrate 11, a second substrate 12, an electrochromic element 30 (EC element 30), and a sealing portion 40. The sealing portion 40 is omitted in FIG.

[0036] The first substrate 11 and the second substrate 12 sandwich the EC element 30 and the sealing portion 40. The sealing portion 40 is disposed around the EC element 30 between the first substrate 11 and the second substrate 12, and partitions the space between the first substrate 11 and the second substrate 12. The area partitioned by the sealing portion 40 is a colored area AR whose color changes when a voltage is applied.

[0037] [First Substrate, Second Substrate] The first substrate 11 and the second substrate 12 are the outermost layers of the EC sheet 150. The first substrate 11 and the second substrate 12 are arranged opposite to each other and function as protective layers that protect the EC element 30 and the like.

[0038] The first substrate 11 and the second substrate 12 are visible light transmissive. In this specification, having visible light transmissive property may be referred to as "transparency." Visible light transmissive property may also be referred to as "transparency." If the first substrate 11 and the second substrate 12 are transparent, they may be colorless or colored.

[0039] The first substrate 11 and the second substrate 12 contain a transparent thermoplastic resin as a main material, such as an acrylic resin, a polystyrene resin, a polyethylene resin, a polypropylene resin, a polyester resin (such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN)), a polycarbonate resin, a polyamide resin, a cycloolefin resin, a vinyl chloride resin, a polyacetal resin, or triacetyl cellulose (TAC).

[0040] One of the above resins may be used alone or two or more of them may be used in combination as the material for the first substrate 11 and the second substrate 12. The material for the first substrate 11 and the second substrate 12 is preferably a polycarbonate-based resin or a polyamide-based resin.

[0041] Furthermore, as long as the material has transparency, it may contain a known filler or additive in the material of the first substrate 11 and the second substrate 12. Furthermore, the first substrate 11 and the second substrate 12 may be a single layer or a laminate.

[0042] The refractive index of the first substrate 11 and the second substrate 12 at a wavelength of 589 nm is preferably 1.3 or more and 1.8 or less, and more preferably 1.4 or more and 1.65 or less. By setting the refractive index of the first substrate 11 and the second substrate 12 to this range, the function of the electrochromic element 30 can be improved.

[0043] The average thickness of the first substrate 11 and the second substrate 12 is, for example, 0.05 mm or more and 10.0 mm or less, and preferably 0.3 mm or more and 5.0 mm or less.

[0044] [Electrochromic Element] The EC element 30 changes color (coloring or decoloring) due to electrochromism caused by application of a voltage. The EC element 30 has a first transparent electrode 31, a second transparent electrode 32, a first auxiliary electrode 33, a second auxiliary electrode 34, and an electrochromic layer 35 (EC layer 35).

[0045] (First Transparent Electrode, Second Transparent Electrode) The first transparent electrode 31 is provided on the first substrate 11 side of the EC element 30, and is formed on the surface of the first substrate 11 facing the second substrate 12. The second transparent electrode 32 is provided on the second substrate 12 side of the EC element 30, and is formed on the surface of the second substrate 12 facing the first substrate 11.

[0046] 2, the first transparent electrode 31 has a protruding portion 31a at a position overlapping a first extraction portion 332 (described later) similar to the first extraction portion 332, but this portion 31a may be omitted. Similarly, the second transparent electrode 32 has a protruding portion 32a at a position overlapping a second extraction portion 342 (described later) similar to the second extraction portion 342, but this portion 32a may be omitted.

[0047] The first transparent electrode 31 and the second transparent electrode 32 are transparent. Examples of materials for the first transparent electrode 31 and the second transparent electrode 32 include ITO, F-doped tin oxide (FTO), antimony tin oxide (ATO), indium zinc oxide (IZO), and indium zinc oxide (IZO). ２ O ３ , SnO ２ , Sb-containing SnO ２, oxides such as Al-containing ZnO, Au, Pt, Ag, Cu, or alloys containing these, etc. The first transparent electrode 31 and the second transparent electrode 32 may be made of one of these materials or a combination of two or more of these materials.

[0048] The thicknesses of the first transparent electrode 31 and the second transparent electrode 32 are adjusted to ensure the necessary transparency and to obtain an electrical resistance value that allows an appropriate voltage to be applied to the EC layer 35. When ITO is used as the material for the first transparent electrode 31 and the second transparent electrode 32, the average thickness of the first transparent electrode 31 and the average thickness of the second transparent electrode 32 are, for example, independently set to 50 nm or more and 200 nm or less, preferably 50 nm or more and 150 nm or less, and more preferably 60 nm or more and 130 nm or less. The upper and lower limit values ​​of the average thickness of the first transparent electrode 31 and the upper and lower limit values ​​of the average thickness of the second transparent electrode 32 can be combined in any desired manner.

[0049] (First Auxiliary Electrode, Second Auxiliary Electrode) The first auxiliary electrode 33 and the second auxiliary electrode 34 are spaced apart in the circumferential direction of the colored region AR and are arranged around the colored region AR, so that the first auxiliary electrode 33 and the second auxiliary electrode 34 surround the colored region AR.

[0050] The first auxiliary electrode 33 is disposed around the colored region AR on the periphery of the first transparent electrode 31, and is electrically connected to the first transparent electrode 31. The first auxiliary electrode 33 has a strip-shaped first frame 331 and a first extraction portion 332 that protrudes from the first frame 331 to the outside of the colored region AR.

[0051] The first frame 331 surrounds a portion of the EC layer 35, i.e., a portion of the colored region AR. The first frame 331 is curved in a plan view, but is not limited to this. When the first frame 331 is formed as the lens 110, the first frame 331 is provided in a position that surrounds the periphery of the lens 110. The width of the first frame 331 is preferably, for example, 0.1 mm to 1.0 mm, and more preferably 0.3 mm to 1.0 mm.

[0052] The first extraction portion 332 is provided at one end of the first frame 331. The first extraction portion 332 is provided at a position in the frame 120 that will be near the bridge portion 122 or the temple portion 123 when the lens 110 is installed.

[0053] The second auxiliary electrode 34 is disposed around the colored region AR on the peripheral surface of the second transparent electrode 32, and is electrically connected to the second transparent electrode 32. The second auxiliary electrode 34 has a strip-shaped second frame 341 and a second extraction portion 342 that protrudes from the second frame 341 to the outside of the colored region AR.

[0054] The second frame 341 surrounds a portion of the EC layer 35, i.e., a portion of the colored region AR. The second frame 341 is curved in a plan view, but is not limited to this. When the second frame 341 is formed as the lens 110, the second frame 341 is provided in a position that surrounds the periphery of the lens 110. The width of the second frame 341 is preferably, for example, 0.1 mm to 1.0 mm, and more preferably 0.3 mm to 1.0 mm.

[0055] The second extraction portion 342 is provided at one end of the second frame 341. The second extraction portion 342 is provided at a position in the frame 120 that will be near the bridge portion 122 or the temple portion 123 when the lens 110 is installed.

[0056] The positions of the first extraction portion 332 and the second extraction portion 342 can be adjusted as appropriate depending on the design of the lens 110 to be manufactured.

[0057] As will be described later, when the EC sheet 150 is processed into the lens 110, a through hole 40a is formed in the sealing portion 40 at a position that overlaps the first extraction portion 332 in plan view, exposing the first extraction portion 332, and a conductive portion 51 is formed in the through hole 40a. The first extraction portion 332 is used as a connection point with the conductive portion 51. The formed conductive portion 51 is electrically connected to the first extraction portion 332 (first auxiliary electrode 33).

[0058] Similarly, a through hole exposing the second extraction portion 342 is formed in the sealing portion 40 at a position overlapping the second extraction portion 342 in plan view, and a conductive portion is formed in the through hole. The second extraction portion 342 is used as a connection point with the conductive portion. The formed conductive portion is electrically connected to the second extraction portion 342 (second auxiliary electrode 34).

[0059] The electrical resistance of the first auxiliary electrode 33 is lower than the electrical resistance of the first transparent electrode 31. Similarly, the electrical resistance of the second auxiliary electrode 34 is lower than the electrical resistance of the second transparent electrode 32. Examples of materials for the first auxiliary electrode 33 and the second auxiliary electrode 34 include silver, aluminum, copper, chromium, and molybdenum. Conductive ink can also be used as the material for the first auxiliary electrode 33 and the second auxiliary electrode 34. The first auxiliary electrode 33 and the second auxiliary electrode 34 may be made of one of these materials or a combination of two or more of these materials. The first auxiliary electrode 33 and the second auxiliary electrode 34 can be formed by, for example, sputtering, vapor deposition, or the like. The first auxiliary electrode 33 and the second auxiliary electrode 34 can also be formed by printing using conductive ink.

[0060] The average thickness of the first auxiliary electrode 33 and the average thickness of the second auxiliary electrode 34 are each preferably independently 1 nm or more and 300 nm or less. The average thickness of the first auxiliary electrode 33 and the average thickness of the second auxiliary electrode 34 are more preferably 150 nm or more and 250 nm or less. The upper and lower limit values ​​of the average thickness of the first auxiliary electrode 33 and the upper and lower limit values ​​of the average thickness of the second auxiliary electrode 34 can be combined in any desired manner.

[0061] 4 is a plan view showing an example of the EC sheet 150. As shown in FIG. 4, the first auxiliary electrode 33 and the second auxiliary electrode 34 do not overlap each other in a plan view and are located on opposite sides of the colored region AR in a plan view. Furthermore, the first extraction portion 332 does not overlap the second transparent electrode 32, and the second extraction portion 342 does not overlap the first transparent electrode 31.

[0062] The first extraction portion 332 provided at one end of the first frame 331 of the first auxiliary electrode 33 and the second extraction portion 342 provided at one end of the second frame 341 of the second auxiliary electrode 34 are disposed in close proximity in a plan view. The first extraction portion 332 and the second extraction portion 342 are spaced apart by more than 0 mm and not more than 10 mm in a plan view. In FIG. 4 , the distance between the first extraction portion 332 and the second extraction portion 342 in a plan view is indicated by the symbol W1. That is, in this embodiment, the distance W1 is more than 0 mm and not more than 10 mm.

[0063] Similarly, the other end 331x of the first frame 331 and the other end 341x of the second frame 341 are disposed close to each other in a plan view. The other end 331x of the first frame 331 and the other end 341x of the second frame 341 are spaced apart by more than 0 mm and not more than 20 mm in a plan view. In FIG. 4 , the distance between the other ends 331x and 341x in a plan view is indicated by the symbol W2. That is, in this embodiment, the distance W2 is more than 0 mm and not more than 20 mm.

[0064] The distance between the first extraction portion 332 and the second extraction portion 342 refers to the shortest distance between them in a plan view. Similarly, the distance between the other end 331x and the other end 341x refers to the shortest distance between them in a plan view.

[0065] The difference between the total length of the first frame 331 and the total length of the second frame 341 is preferably small, and preferably not more than twice the difference between them. For example, the total length of the first frame 331 is preferably more than 50% and less than 200% of the total length of the second frame 341, and more preferably 55% to 175%. Furthermore, the total length of the first frame 331 is preferably 58% to 165% of the total length of the second frame 341, more preferably 61% to 155%, and even more preferably 65% ​​to 145%. The upper and lower limits can be combined in any manner.

[0066] (Electrochromic Layer) As shown in Figures 2 and 3, the EC layer 35 has a first electrochromic layer 351 (first EC layer 351) laminated on the first transparent electrode 31, a second electrochromic layer 352 (second EC layer 352) laminated on the second transparent electrode 32, and an electrolyte layer 353 filled between the first EC layer 351 and the second EC layer 352.

[0067] (First Electrochromic Layer) The first EC layer 351 is a layer whose color changes and contains, as a main material, a material that changes color through an oxidation reaction. Examples of materials that change color through an oxidation reaction include known materials that exhibit electrochromism and are used in EC elements, such as polymers of radical polymerizable compounds having a triarylamine structure, bisacridan compounds, triphenylamine, benzidine, Prussian blue complexes, and nickel oxide.

[0068] Examples of polymers of radically polymerizable compounds having a triarylamine structure include those described in JP-A-2016-45464 and JP-A-2020-138925.

[0069] As the material that is colored by an oxidation reaction, one of these may be used, or two or more of them may be used in combination.

[0070] The average thickness of the first EC layer 351 is preferably 0.1 μm or more and 30 μm or less. The average thickness of the first EC layer 351 is more preferably 0.4 μm or more and 10 μm or less. The upper and lower limit values ​​of the average thickness of the first EC layer 351 can be combined arbitrarily.

[0071] (Second Electrochromic Layer) The second EC layer 352 is a color-changing layer and contains, as a main material, a material that changes color through a reduction reaction. Examples of materials that change color through a reduction reaction include known materials that exhibit electrochromism and are used in EC elements, such as inorganic electrochromic compounds such as tungsten oxide, molybdenum oxide, iridium oxide, and titanium oxide, and organic electrochromic compounds such as viologen-based compounds and dipyridine-based compounds.

[0072] As the material that is colored by a reduction reaction, one of these may be used, or two or more of them may be used in combination.

[0073] The color (color 1) that the first EC layer 351 is colored by an oxidation reaction and the color (color 2) that the second EC layer 352 is colored by a reduction reaction may be the same color tone or different color tones. When color 1 and color 2 are the same color tone, the maximum color density can be increased and the contrast can be improved. When color 1 and color 2 are different color tones, the color that the EC element 30 emits is the color obtained by mixing color 1 and color 2.

[0074] By coloring both the first EC layer 351 and the second EC layer 352, the redox dyes of the first EC layer 351 and the second EC layer 352 can simultaneously develop colors, thereby improving the color development speed.

[0075] The average thickness of the second EC layer 352 is preferably 0.2 μm or more and 5.0 μm or less. The average thickness of the second EC layer 352 is more preferably 1.0 μm or more and 4.0 μm or less. When the average thickness of the second EC layer 352 is 0.2 μm or more, the color density can be increased. When the average thickness of the second EC layer 352 is 5.0 μm or less, the manufacturing cost can be reduced. When the average thickness of the second EC layer 352 is 5.0 μm or less, a decrease in visibility due to coloring is unlikely to occur. The upper and lower limit values ​​of the average thickness of the second EC layer 352 can be arbitrarily combined.

[0076] (Electrolyte Layer) The electrolyte layer 353 is filled between the first EC layer 351 and the second EC layer 352. The electrolyte layer 353 contains an electrolyte having ion conductivity.

[0077] Examples of the electrolyte include inorganic ion salts such as alkali metal salts and alkaline earth metal salts; and supporting salts such as quaternary ammonium salts, acids, and alkalis. Counter ions (anions) of the electrolyte include halogens, thiocyanate ions (SCN － ), chlorate ion (ClO ３ － ), perchlorate ion (ClO ４ － ), tetrafluoroborate ion (BF４ － ), hexafluorophosphate ion (PF ６ － ), trifluoromethanesulfonate ion (CF ３ SO ３ － ), trifluoroacetate ion (CF ３ COO － ), bisfluorosulfonium imide (N(SO ２ F) ２ － ) can be mentioned.

[0078] Specific examples of such electrolytes include 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 As the electrolyte, one of these may be used, or two or more of them may be used in combination.

[0079] Ionic liquids can also be used as electrolyte materials. Among ionic liquids, organic ionic liquids have a molecular structure that allows them to remain liquid over a wide temperature range, including room temperature, and are therefore easy to handle.

[0080] The average thickness of the electrolyte layer 353 is preferably 20 μm or more and 100 μm or less. The average thickness of the electrolyte layer 353 is more preferably 30 μm or more and 80 μm or less, and even more preferably 30 μm or more and 70 μm or less. The upper and lower limit values ​​of the average thickness of the electrolyte layer 353 can be combined arbitrarily.

[0081] [Sealing portion] The sealing portion 40 is disposed between the first substrate 11 and the second substrate 12, and defines the colored region AR. The material of the sealing portion 40 is not particularly limited as long as it is an insulating material having transparency. Examples of the material of the sealing portion 40 include resin materials such as acrylic resin and epoxy resin; silicon oxide (SiO ２ ), silicon oxynitride (SiON), aluminum oxide (Al ２ O ３ ) and other inorganic oxides.

[0082] The average thickness of the sealing portion 40 is adjusted depending on the average thickness of the EC element 30. The average thickness of the sealing portion 40 is preferably 20 μm or more and 100 μm or less, more preferably 30 μm or more and 80 μm or less, and even more preferably 40 μm or more and 60 μm or less. The upper and lower limit values ​​of the average thickness of the sealing portion 40 can be combined in any desired manner.

[0083] Such an EC sheet 150 has the following effects, for example.

[0084] First, because the first extraction portion 332 and the second extraction portion 342 are located close to each other, when the lens 110 is formed, there is only one portion that protrudes outward from the lens 110. Therefore, there is more freedom in design compared to when the first extraction portion 332 and the second extraction portion 342 are located at separate positions and there are two portions that protrude outward from the lens 110.

[0085] Furthermore, previous knowledge has suggested that if the wiring positions of the two extraction portions are close to each other, when the EC sheet is driven, the color change occurs immediately in the colored area AR near the two extraction portions, but the color change occurs later in positions relatively far from the extraction portions, resulting in unevenness in the change. In contrast, in the EC sheet 150 of this embodiment, it has been found that unevenness in the color change can be suppressed by similarly positioning the other end 331x of the first frame 331 and the other end 341x of the second frame 341 close to each other in a plan view.

[0086] To evaluate this effect, an EC sheet 150 was fabricated using ITO with a thickness of 100 nm as the transparent electrode material and silver with a thickness of 2000 nm and a width of 0.3 mm as the auxiliary electrode material, with a distance W1 of 1.5 mm and a distance W2 of 20 mm, and the color change in the colored region AR was evaluated. As a result of the evaluation, visual evaluation confirmed that there was no unevenness in the color change in the colored region AR.

[0087] In contrast, an EC sheet was produced in which the distance W2 was outside the specified range of more than 0 mm and 20 mm or less, and when it was driven under the same conditions, it was confirmed by visual evaluation that there was clearly unevenness in the color change.

[0088] The reason why the EC sheet 150 of this embodiment is less likely to cause uneven color change in the colored areas AR can be considered as follows.

[0089] If the distance W2 is increased, an imaginary line connecting the auxiliary electrode ends (the other end 331x of the first frame 331 and the other end 341x of the second frame 341) may cross the colored region AR. In such an arrangement, it is assumed that it becomes difficult to pass electricity to the colored region AR located outside the imaginary line (on the outer periphery of the colored region AR), and color development is thought to be delayed.

[0090] On the other hand, by setting the distance W2 to be more than 0 mm and not more than 20 mm, the above-mentioned effect can be suppressed to a level that is difficult to notice visually, and current can be quickly passed through the entire surface, which is thought to result in no unevenness in the color change.

[0091] <Laminate, Eyeglass Lens> FIG. 5 is an explanatory diagram illustrating a method for manufacturing a lens using the EC sheet 150. As shown in FIG.

[0092] 5A, the EC sheet 150 is bent under heat to curve the EC sheet 150 to match the curvature of the target lens. The bending is performed by, for example, press molding or vacuum forming.

[0093] 5(b), the curved EC sheet 150 is insert-molded as an insert, and a lens material 119 is formed on the concave surface of the EC sheet 150 to obtain a laminate 160. The laminate 160 corresponds to the "laminate" of the present invention. The lens material 119 becomes the lens body 115 by processing as described below.

[0094] The lens material 119 has a visible light transmittance and may be made of a thermoplastic resin known as a material for optical members.

[0095] It is preferable that the material of the lens material 119 is the same as or the same as the main material of the substrate (first substrate 11 or second substrate 12) that contacts the lens material 119 in the EC sheet 150, as this facilitates close contact between the EC sheet 150 and the lens material 119. Furthermore, if the materials of the substrate and the lens material 119 are the same as or the same, the difference in refractive index between the substrate and the lens material 119 can be reduced, and light scattering and reflection at the interface between the EC sheet 150 and the lens material 119 can be suppressed. The difference in refractive index between the substrate and the lens material 119 is preferably 0.2 or less, and more preferably 0.1 or less.

[0096] The thickness of the lens material 119 is preferably, for example, 1.5 mm or more and 20 mm or less. By setting the thickness of the lens material 119 within this range, it is possible to achieve both high strength and light weight for the obtained lens.

[0097] Next, the surface of the lens material 119 is polished, and the surfaces of the EC sheet 150 and the lens material 119 are hard-coated and anti-reflection-treated. After that, a through hole exposing the first extraction portion 332 and a through hole exposing the second extraction portion 342 are formed in the sealing portion 40 at positions overlapping with the first extraction portion 332 and the second extraction portion 342. A conductive portion 51 electrically connected to the first extraction portion 332 and a conductive portion 52 electrically connected to the second extraction portion 342 are formed in the through holes.

[0098] The conductive portions 51 and 52 can be formed by a conductive paste filled in the through-holes or a conductive cylindrical member inserted into the through-holes. Alternatively, any known material can be used as appropriate as long as it is formed in the through-holes and can be electrically connected to the first auxiliary electrode 33 (first extraction portion 332) and the second auxiliary electrode 34 (second extraction portion 342).

[0099] 5(c), the laminate 160 is trimmed to a shape corresponding to the rim portion 121 of the above-described sunglasses 100. At this time, trimming of the peripheries of the first extraction portion 332 and the second extraction portion 342 is performed using, for example, a rotating cylindrical grindstone G.

[0100] By this processing, a lens 110 is obtained that includes an EC portion 111 obtained by cutting the EC sheet 150 along the outer peripheries of the first auxiliary electrode 33 and the second auxiliary electrode 34, and a lens body 115 in which the EC portion 111 is laminated (see FIG. 1 ). The obtained lens 110 corresponds to the "eyeglass lens" of the present invention.

[0101] The lens material 119 of the laminate 160 is processed into a lens body 115 by trimming along the outer peripheries of the first auxiliary electrode 33 and the second auxiliary electrode 34. The lens body 115 has a protrusion 115a that has the same shape as the first extraction portion 332 and the second extraction portion 342 in a plan view. The first extraction portion 332 and the second extraction portion 342 are arranged on the protrusion 115a.

[0102] The obtained lens 110 is combined with the frame 120 shown in Fig. 1. At this time, the first and second extraction portions 332, 342 of the EC unit 111 are electrically connected to the frame 120 via the conductive portions provided thereon. In this embodiment, the first and second extraction portions 332, 342 are electrically connected to external terminals (not shown) provided on the temple portion 123 or the bridge portion 122 of the frame 120, and are connected to the battery 126. In this way, the sunglasses 100 are obtained.

[0103] Since it is easier to hide the first auxiliary electrode 33, the second auxiliary electrode 34, and the sealing portion 40 of the EC sheet 150, the eyeglasses (sunglasses 100) to which the lenses 110 are applied are preferably designed with a frame rather than a frameless design that does not have a frame surrounding the periphery of the lens. For the same reason, eyeglasses to which the lenses 110 are applied are preferably designed with a frame that surrounds the entire periphery of the lens rather than a half-rim type design.

[0104] The shape of the lens 110 is not particularly limited and can be appropriately adopted depending on the design. For example, the lens shape can be a shape that matches known frame shapes such as Wellington, Thermont (Brow), Boston, Teardrop, Lexington, Square, Round, Oval, Fox, etc.

[0105] According to the electrochromic sheet having the above-described configuration, the presence of the first auxiliary electrode 33 and the second auxiliary electrode 34 enables coloring and decoloring to occur without delay.

[0106] Furthermore, the laminate, eyeglass lens, and eyeglasses having the above-described configurations can develop and decolorize without delay by virtue of having the electrochromic sheet.

[0107] In this embodiment, sunglasses 100 are shown as an example of eyeglasses, but the present invention is not limited to this. The lens 110 may be applied to, for example, goggles that protect the eyes from wind, rain, dust, chemicals, etc. Alternatively, the lens 110 may be applied to a wearable device, such as smart glasses, that is worn on the user's head with the lens 110 positioned in front of the user's eyes.

[0108] In addition, in the present embodiment, the EC layer 35 includes the first EC layer 351 and the second EC layer 352, but this is not limitative. Even if the EC layer 35 includes only one of the first EC layer 351 and the second EC layer 352, the effects of the present invention can be achieved.

[0109] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. The shapes and combinations of the components shown in the above examples are merely examples, and various modifications can be made based on the design, specifications, etc., without departing from the spirit of the present invention.

[0110] REFERENCE SIGNS LIST 11...first substrate, 12...second substrate, 30...electrochromic element (EC element), 31...first transparent electrode, 32...second transparent electrode, 33...first auxiliary electrode, 34...second auxiliary electrode, 35...electrochromic layer (EC layer), 40...sealing portion, 110...lens, 111...electrochromic portion (EC portion), 115...lens body, 115a...protrusion, 119...lens material, 120...frame, 150...electrochromic sheet (EC sheet), 160...laminated body, 331...first frame, 331x, 341x...other end, 332...first extraction portion, 341...second frame, 342...second extraction portion, 351...first electrochromic layer (first EC layer), 352...second electrochromic layer (second EC layer), 353...electrolyte layer, AR...colored region

Claims

1. A first substrate, a second substrate, an electrochromic element sandwiched between the first substrate and the second substrate, and a sealing portion sandwiched between the first substrate and the second substrate and partitioning a coloring region set between the first substrate and the second substrate, wherein the electrochromic element includes a first transparent electrode provided on the first substrate side, a first auxiliary electrode electrically connected to the first transparent electrode, a second transparent electrode provided on the second substrate side, a second auxiliary electrode electrically connected to the second transparent electrode, and an electrochromic layer sandwiched between the first transparent electrode and the second transparent electrode, disposed in the coloring region, and colored by applying a voltage. The first auxiliary electrode and the second auxiliary electrode are spaced apart in the circumferential direction of the coloring region and disposed around the coloring region. The first auxiliary electrode includes a strip-shaped first frame body surrounding a part of the electrochromic layer, and a first extraction portion provided at one end of the first frame body and protruding outward from the first frame body to the outside of the coloring region. The second auxiliary electrode includes a strip-shaped second frame body surrounding a part of the electrochromic layer, and a second extraction portion provided at one end of the second frame body and protruding outward from the second frame body to the outside of the coloring region. The first extraction portion and the second extraction portion are spaced apart by more than 0 mm and 10 mm or less in plan view, and the other end of the first frame body and the other end of the second frame body are spaced apart by more than 0 mm and 20 mm or less in plan view. An electrochromic sheet.

2. The electrochromic sheet according to claim 1, wherein the total length of the first frame body is more than 50% and less than 200% of the total length of the second frame body.

3. The electrochromic layer includes a first electrochromic layer laminated on the first transparent electrode, a second electrochromic layer laminated on the second transparent electrode, and an electrolyte layer filled between the first electrochromic layer and the second electrochromic layer. The first electrochromic layer contains a material that exhibits coloring by an oxidation reaction, and the second electrochromic layer contains a material that exhibits coloring by a reduction reaction. The electrochromic sheet according to claim 1 or 2.

4. A laminate including the electrochromic sheet according to claim 1 and a lens material on which the electrochromic sheet is laminated.

5. An electrochromic sheet according to claim 1, comprising: an electrochromic part obtained by cutting along the outer peripheries of the first auxiliary electrode and the second auxiliary electrode; and a lens body on which the electrochromic part is laminated, wherein the lens body is an eyeglass lens having a protruding part that is the same shape as the first extraction part and the second extraction part in plan view.

6. An eyeglass lens according to claim 5, and a frame for holding the eyeglass lens, wherein the first extraction part and the second extraction part are eyeglasses that are electrically connected to the frame.

Images