Electrochromic sheet, laminate, spectacle lens and spectacle

Abstract

To provide an electrochromic sheet capable of quick color development, a laminate, a spectacle lens, and a spectacle.SOLUTION: An electrochromic sheet comprises a first substrate, a second substrate, an EC element, and an encapsulating part. The EC element includes a first transparent electrode, a second transparent electrode, and an EC layer. When impedance of the EC sheet per unit area is measured under the condition of applied voltage of 0 V and amplitude of 10 mV within a range of response frequency from 0.1 Hz to 1 MHz, the following requirements (1) to (3) are satisfied in Nyquist diagram obtained from the measurement result. (1) A first intersection point of a horizontal axis of the Nyquist diagram and chart is 1.0 Ω / cm2 or more and 8.0 Ω / cm2 or less. (2) Approximation straight line of the chart of imaginary number component falls within a range of 7.0 Ω / cm2 or more and 14.0 Ω / cm2 or less is inclined at 25 or less. (3) A value ([value of second intersection point between approximation straight line and horizontal axis]-[value of first intersection point]) is 5.0 Ω / cm2 or less.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an electrochromic sheet, a laminate, an eyeglass lens, and eyeglasses. [Background technology]

[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] An 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. They are also used as light-adjusting components (optical filters) in windows and imaging devices. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-167317 Summary of the Invention [Problem to be solved by the invention]

[0006] Electrochromic sheets are required to quickly develop color upon application of voltage. In other words, electrochromic sheets are required to "easily change color" during the color change process upon application of voltage. In this respect, the electrochromic sheet described in Patent Document 1 has room for improvement.

[0007] The present invention has been made in view of the above circumstances, and aims to provide an electrochromic sheet capable of rapid color development, as well as a laminate including such an electrochromic sheet, an eyeglass lens, and eyeglasses including the eyeglass lens. [Means for solving the problem]

[0008] In order to solve the above problems, one aspect of the present invention includes the following aspects.

[0009] [1] An electrochromic sheet 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 second transparent electrode provided on the second substrate side, 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; when the impedance per unit area of ​​the electrochromic sheet is measured under conditions of an applied voltage of 0 V and an amplitude of 10 mV in a response frequency range of 0.1 Hz to 1 MHz, the Nyquist diagram obtained from the measurement results satisfies the following requirements (1) to (3): (1) The horizontal axis of the Nyquist diagram and the graph of the Nyquist diagram are 0 Ω / cm 2 More than 8.0Ω / cm 2 The first intersection point in the following range is 1.0 Ω / cm 2 More than 8.0Ω / cm 2 Included in the following range: (2) The imaginary component is 7.0 Ω / cm 2 More than 14.0Ω / cm 2 In the following range, when the graph is approximated as a straight line, the gradient of the approximated line is 25 or less. (3) The following A value is 5.0Ω / cm 2 The following is the result. A value = [value of the second intersection point between the approximation line and the horizontal axis] - [value of the first intersection point]

[0010] [2] The A value is 0Ω / cm 2 More than 5.0Ω / cm 2 The electrochromic sheet according to [1] below.

[0011] [3] An electrochromic sheet according to [1] or [2], comprising a first auxiliary electrode electrically connected to the first transparent electrode and a second auxiliary electrode electrically connected to the second transparent electrode, the first auxiliary electrode and the second auxiliary electrode being spaced apart in the circumferential direction of the colored region and being arranged around the colored region.

[0012] [4] The electrochromic sheet according to any one of [1] to [3], 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.

[0013] [5] A laminate comprising the electrochromic sheet according to any one of [1] to [4] and a lens material on which the electrochromic sheet is laminated.

[0014] [6] A spectacle lens comprising an electrochromic portion obtained by cutting the electrochromic sheet described in any one of [1] to [4], and a lens body on which the electrochromic portion is laminated.

[0015] [7] Eyeglasses comprising the eyeglass lens according to [6] and a frame that holds the eyeglass lens, wherein the eyeglass lens is electrically connected to the frame. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide an electrochromic sheet capable of rapid color development, a laminate including such an electrochromic sheet, an eyeglass lens, and eyeglasses including the eyeglass lens. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view showing sunglasses (eyeglasses) using the electrochromic sheet of the embodiment as a material. [Figure 2] FIG. 2 is an exploded perspective view of the electrochromic sheet 150. As shown in FIG. [Figure 3] FIG. 3 is a partial cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a plan view showing an example of the EC sheet 150. As shown in FIG. [Figure 5] FIG. 5 is an example of a Nyquist diagram obtained from the AC impedance measurement results of the EC sheet 150. [Figure 6] FIG. 6 is an explanatory diagram illustrating a method for manufacturing a lens using the EC sheet 150. [Figure 7] FIG. 7 is a Nyquist diagram of each EC sheet evaluated in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0018] The electrochromic sheet, laminate, eyeglass lens, and eyeglasses according to the present embodiment will be described below with reference to Figures 1 to 7. 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."

[0019] ≪Glasses≫ 1 is a perspective view showing sunglasses (eyeglasses) made from the electrochromic sheet (EC sheet) of this embodiment. Sunglasses are an example of eyeglasses.

[0020] 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.

[0021] As shown in FIG. 1, sunglasses 100 include a pair of lenses 110 (eyeglass lenses) and a frame 120.

[0022] [lens] Lens 110 is transparent to visible light and can reversibly develop or fade color by switching the voltage applied. In this specification, the term "lens (eyeglass lens)" includes both lenses with and without a light-condensing function.

[0023] 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 side, and the EC portion 111 is located on the surface of the lens body 115 opposite the user.

[0024] 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 eyes of the user.

[0025] 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 not have the rim portions 121.

[0026] The bridge portion 122 connects the pair of rim portions 121. When worn on the user's head, the bridge portion 122 is located in front of the top of the user's nose.

[0027] 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.

[0028] 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.

[0029] The battery 126 is built into the temple portion 123. The battery 126 is electrically connected to the lens 110 via a wire.

[0030] The nose pads 124 are formed on each rim 121 at positions corresponding to the nose of the user. The nose pads 124 come into contact with the nose of the user. The nose pads 124 stabilize the wearing state of the sunglasses 100.

[0031] 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.

[0032] <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.

[0033] 2 and 3, the EC sheet 150 has a first substrate 11, a second substrate 12, an electrochromic element 30 (EC element 30), and a sealing portion 40. In Fig. 2, the sealing portion 40 is omitted.

[0034] 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.

[0035] [First board, second board] 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 disposed opposite to each other and function as protective layers that protect the EC element 30 and the like.

[0036] 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 they are transparent, the first substrate 11 and the second substrate 12 may be colorless or colored.

[0037] First substrate 11 and second substrate 12 contain a transparent thermoplastic resin as a main material, such as acrylic resin, polystyrene resin, polyethylene resin, polypropylene resin, polyester resin (polyethylene terephthalate (PET), polyethylene naphthalate (PEN), etc.), polycarbonate resin, polyamide resin, cycloolefin resin, vinyl chloride resin, polyacetal resin, triacetyl cellulose (TAC), etc.

[0038] One of the above resins may be used, or two or more 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.

[0039] Furthermore, as long as the materials of first substrate 11 and second substrate 12 are transparent, they may contain known fillers or additives. Furthermore, first substrate 11 and second substrate 12 may be single layers or laminates.

[0040] 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 within this range, the function of the electrochromic element 30 can be improved.

[0041] 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.

[0042] [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, and an electrochromic layer 35 (EC layer 35). The EC element 30 may also have a first auxiliary electrode 33 and a second auxiliary electrode 34.

[0043] (1st transparent electrode, 2nd 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.

[0044] 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 absent. 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 absent.

[0045] 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 oxides such as ITO, FTO (F-doped tin oxide), ATO (antimony tin oxide), IZO (indium zinc oxide), In2O3, SnO2, Sb-containing SnO2, and Al-containing ZnO, as well as Au, Pt, Ag, Cu, and alloys containing any of these. 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.

[0046] The thickness of the first transparent electrode 31 and the second transparent electrode 32 is adjusted so as 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 second transparent electrode 32 is, 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.

[0047] (1st auxiliary electrode, 2nd 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.

[0048] 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 body 331 and a first extraction portion 332 that protrudes from the first frame body 331 to the outside of the colored region AR.

[0049] 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 or more and 1.0 mm or less, and more preferably 0.3 mm or more and 1.0 mm or less.

[0050] The first extraction portion 332 is provided at one end of the first frame body 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 formed.

[0051] 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 body 341 and a second extraction portion 342 that protrudes from the second frame body 341 to the outside of the colored region AR.

[0052] 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 or more and 1.0 mm or less, and more preferably 0.3 mm or more and 1.0 mm or less.

[0053] 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.

[0054] The positions of the first extraction section 332 and the second extraction section 342 can be adjusted appropriately depending on the design of the lens 110 to be manufactured.

[0055] As will be described later, when the EC sheet 150 is processed into the lens 110, a through-hole 40a exposing the first extraction portion 332 is formed in the sealing portion 40 at a position overlapping the first extraction portion 332 in plan view, 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).

[0056] 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).

[0057] The electrical resistance of the first auxiliary electrode 33 is lower than that of the first transparent electrode 31. Similarly, the electrical resistance of the second auxiliary electrode 34 is lower than that 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 or vapor deposition. The first auxiliary electrode 33 and the second auxiliary electrode 34 can also be formed by printing using conductive ink.

[0058] The average thickness of each of the first auxiliary electrode 33 and the second auxiliary electrode 34 is preferably 1 nm or more and 300 nm or less, and more preferably 150 nm or more and 250 nm or less.

[0059] Fig. 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 with the second transparent electrode 32, and the second extraction portion 342 does not overlap with the first transparent electrode 31.

[0060] 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.

[0061] (electrochromic layer) As shown in Figures 2 and 3, the EC layer 35 has a first electrochromic layer 351 (first EC layer 351) stacked on the first transparent electrode 31, a second electrochromic layer 352 (second EC layer 352) stacked on the second transparent electrode 32, and an electrolyte layer 353 filled between the first EC layer 351 and the second EC layer 352.

[0062] (First electrochromic layer) The first EC layer 351 is a color-changing layer, and contains as its main material a material that changes color through oxidation. Examples of materials that change color through oxidation 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.

[0063] Examples of polymers of radically polymerizable compounds having a triarylamine structure include those described in JP-A-2016-45464 and JP-A-2020-138925.

[0064] 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.

[0065] The average thickness of the first EC layer 351 is preferably 0.1 μm or more and 30 μm or less, and more preferably 0.4 μm or more and 10 μm or less.

[0066] (Second electrochromic layer) The second EC layer 352 is a color-changing layer and contains, as its 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.

[0067] 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.

[0068] The color (color 1) that the first EC layer 351 acquires through an oxidation reaction and the color (color 2) that the second EC layer 352 acquires through a reduction reaction may be the same color tone or different color tones. When color 1 and color 2 have the same color tone, the maximum color density can be increased and contrast can be improved. When color 1 and color 2 have different color tones, the color that the EC element 30 acquires is the color obtained by mixing color 1 and color 2.

[0069] 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.

[0070] 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.

[0071] (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.

[0072] Examples of electrolytes 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. Counterions (anions) of the electrolytes include halogens, thiocyanate ions (SCN - ), chlorate ion (ClO3 - ), perchlorate ion (ClO4 - ), tetrafluoroborate ion (BF4 - ), hexafluorophosphate ion (PF6 - ), trifluoromethanesulfonate ion (CF3SO3 -), trifluoroacetate ion (CF3COO - ), bisfluorosulfonium imide (N(SO2F)2 - ) can be mentioned.

[0073] Specific examples of such electrolytes include LiClO4, LiBF4, LiAsF6, LiPF6, LiCF3SO3, LiCF3COO, KCl, NaClO3, NaCl, NaBF4, NaSCN, KBF4, Mg(ClO4)2, Mg(BF4)2, etc. As the electrolyte, one of these may be used, or two or more of them may be used in combination.

[0074] 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.

[0075] The average thickness of the electrolyte layer 353 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 30 μm or more and 70 μm or less.

[0076] [Sealing part] The sealing portion 40 is disposed between the first substrate 11 and the second substrate 12, and defines a colored area AR. The material of the sealing portion 40 is not particularly limited as long as it is a transparent insulating material. Examples of materials for the sealing portion 40 include resin materials such as acrylic resin and epoxy resin; and inorganic oxides such as silicon oxide (SiO), silicon oxynitride (SiON), and aluminum oxide (AlO).

[0077] The average thickness of the sealing portion 40 is adjusted according to 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.

[0078] In order to realize the above-mentioned rapid color development of the EC sheet 150, the inventors focused on the electrical characteristics of the EC sheet 150 in a color-destroyed state and conducted AC impedance measurements and studies in the color-destroyed state. As a result, they found that rapid color development is possible by satisfying the following requirements (1) to (3), and completed the invention.

[0079] When the impedance per unit area of ​​the EC sheet 150 is measured at an applied voltage of 0 V and an amplitude of 10 mV over a response frequency range of 0.1 Hz to 1 MHz, the Nyquist diagram (or Cole-Cole plot) obtained from the measurement results satisfies the following requirements (1) to (3): (1) The horizontal axis of the Nyquist diagram and the graph of the Nyquist diagram are plotted against each other at 0 Ω / cm 2 More than 8.0Ω / cm 2 The first intersection point in the following range is 1.0 Ω / cm 2 More than 8.0Ω / cm 2 Included in the following range: (2) The imaginary component is 7.0 Ω / cm 2 More than 14.0Ω / cm 2 In the following range, when the graph is approximated as a straight line, the slope of the approximate line is 25 or less. (3) The following A value is 5.0Ω / cm 2 The following is the result. A value = [value of the second intersection point between the approximate line and the horizontal axis] - [value of the first intersection point]

[0080] Fig. 5 is an example of a Nyquist diagram obtained from the results of measuring the AC impedance of the EC sheet 150. The AC impedance measurement was performed in a thermostatic chamber at 25°C. The Nyquist diagram is a complex plane showing the results of the AC impedance measurement, and it is known that the horizontal axis represents the real component of the impedance (resistance) and the vertical axis represents the imaginary component of the impedance (capacitive reactance). In Fig. 5, the graph of the Nyquist diagram is indicated by the symbol G.

[0081] The value of the first intersection P1, which satisfies requirement (1), mainly represents the resistance of the transparent electrodes (first transparent electrode 31, second transparent electrode 32).2 More than 8.0Ω / cm 2 The EC sheet 150 has a first intersection point P1 of 8.0 Ω / cm or less. 2 Compared to EC sheets with high resistance exceeding 100%, the color development speed is faster.

[0082] The value of the first intersection point P1 is 1.2Ω / cm 2 The value of the first intersection point P1 may be 6.0 Ω / cm or more. 2 may be less than 4.0 Ω / cm 2 It is preferable that the following is true:

[0083] The slope of requirement (2) is thought to affect the color development speed. In Figure 5, the approximate line is indicated by the symbol PL.

[0084] FIG. 5 is an enlarged view showing the vicinity of the origin (high-frequency region (low-resistance region)) of the Nyquist diagram. It is known that in the Nyquist diagram, the graph traces a roughly semicircular locus that intersects with the horizontal axis (third intersection) in the low-frequency region (high-resistance region). This third intersection is thought to correlate with the internal resistance of the first EC layer 351 and the second EC layer 352 of the EC sheet.

[0085] In an EC sheet in which the gradient of the approximate line PL defined as requirement (2) is small, the semicircle is small and the third intersection point is small. In such an EC sheet, the internal resistance of the first EC layer 351 and the second EC layer 352 is considered to be relatively small, and the color development speed is considered to be fast.

[0086] That is, the smaller the gradient of the approximate straight line PL, the faster the color development speed of the EC sheet 150 becomes.

[0087] The gradient of the approximate straight line PL is preferably 1 or more and 20 or less, and more preferably 1 or more and 12 or less.

[0088] The A value, which is requirement (3), affects the ease of maintaining the color development of the EC sheet 150. In Fig. 5, the second intersection point is indicated by the symbol P2. If the second intersection point P2 has a smaller value than the first intersection point P1, the A value will be negative.

[0089] In the following description, the property of the EC sheet to maintain its color after it has developed a color may be referred to as "memory property." "Good memory property" means that the EC sheet is likely to maintain its color.

[0090] A value is 0Ω / cm 2 More than 5.0Ω / cm 2 An EC sheet 150 in which the value of the second intersection P2 is equal to or greater than the value of the first intersection P1 is an EC sheet that can achieve both rapid color development and good memory properties. Such an EC sheet 150 is preferable because it can meet the conflicting requirements of "easy color change" during the color change process due to voltage application, and "resistant to color change" after changing to the set color.

[0091] The requirements (1) to (3) can be controlled as follows.

[0092] The value of the first intersection point P1, which is requirement (1), can be controlled by the thickness of the transparent electrodes (first transparent electrode 31, second transparent electrode 32). EC sheets with thick transparent electrodes tend to have a small value of the first intersection point P1, while EC sheets with thin transparent electrodes tend to have a large value of the first lateral tilt P1. On the other hand, thickening the transparent electrodes reduces the transparency of the EC sheet, making it more susceptible to breakage during thermal bending. Therefore, it is advisable to set the thickness of the transparent electrodes taking into consideration the value of the first intersection point P1 and the transparency and susceptibility to breakage of the EC sheet.

[0093] Furthermore, the value of the first intersection point P1 tends to be high when contact is unstable at each interface between the conductive portion 51 and the first extraction portion 331, the conductive portion 52 and the second extraction portion 332, each auxiliary electrode and each transparent electrode, and the like.

[0094] The slope of the approximate line PL, which is requirement (2), is considered to be affected by the internal resistances of the first EC layer 351 and the second EC layer 352. For example, by reducing the thickness of the first EC layer 351 and increasing the concentration of the dye, the internal resistance of the first EC layer 351 can be reduced, and the slope of the approximate line PL can be made smaller.

[0095] The A value, which is requirement (3), is thought to be affected by the resistance at the interface between the first EC layer 351 and the electrolyte layer 353 and the interface between the second EC layer 352 and the electrolyte layer 353. In particular, when manufacturing the EC layer 35, the electrolyte in the electrolyte layer 353 permeates into the first EC layer 351, and the amount of permeation of this electrolyte affects the interfacial resistance between the first EC layer 351 and the electrolyte layer 353. If the amount of permeation of the electrolyte is large, the interfacial resistance between the first EC layer 351 and the electrolyte layer 353 decreases, and the A value tends to decrease (the second intersection point becomes smaller).

[0096] The amount of electrolyte permeation into the first EC layer 351 can be controlled by the pressure time when the first EC layer 351 and the electrolyte layer 353 are stacked and pressed during the production of the EC layer 35.

[0097] The EC sheet 150 of this embodiment satisfies the above requirements (1) to (3), thereby enabling rapid color development.

[0098] <Laminates, eyeglass lenses> FIG. 6 is an explanatory diagram illustrating a method for manufacturing a lens using the EC sheet 150.

[0099] 6(a), 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.

[0100] 6(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 is processed as described below to become the lens body 115.

[0101] The lens material 119 has a visible light transmittance and may be made of a thermoplastic resin known as a material for optical members.

[0102] 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.

[0103] 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.

[0104] 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 331 and a conductive portion 52 electrically connected to the second extraction portion 341 are formed in the through holes.

[0105] The conductive portions 51, 52 can be formed by a conductive paste filled in the through-holes or a conductive cylindrical member inserted in 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).

[0106] 6(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.

[0107] By such processing, a lens 110 is obtained, which includes an EC portion 111 obtained by cutting the EC sheet 150 and a lens body 115 in which the EC portion 111 is laminated (see FIG. 1). In FIG. 6, when cutting the laminate 160, the lens 110 is obtained by cutting along the outer peripheries of the first auxiliary electrode 33 and the second auxiliary electrode 34 of the EC sheet 150. The obtained lens 110 corresponds to the "eyeglass lens" of the present invention.

[0108] The lens material 119 of the laminate 160 is processed into the 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 having the same shape as the first extraction portion 332 and the second extraction portion 342 in a plan view.

[0109] If the first and second extraction portions 332 and 342 of the EC sheet 150 are configured not to protrude from the auxiliary electrodes to the outer periphery, the lens body 115 may not have the protrusion 115a.

[0110] The obtained lens 110 is combined with the frame 120 shown in Fig. 1. At this time, the first extraction portion 332 and the second extraction portion 342 of the EC portion 111 are electrically connected to the frame 120 via the conductive portions provided thereon. In this embodiment, the first extraction portion 332 and the second extraction portion 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. This results in the sunglasses 100.

[0111] The eyeglasses (sunglasses 100) to which the lenses 110 are applied preferably have a framed design rather than a frameless design that does not have a frame surrounding the periphery of the lens, because this makes it easier to hide the auxiliary electrodes 33, 34 and the sealing portion 40 of the EC sheet 150. For the same reason, the eyeglasses to which the lenses 110 are applied preferably have a framed design that surrounds the entire periphery of the lens rather than a half-rim type design.

[0112] 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, and Fox.

[0113] According to the electrochromic sheet having the above-mentioned configuration, the occurrence of defective coloring areas is suppressed.

[0114] Furthermore, the laminate, eyeglass lens, and eyeglasses having the above-described configurations have high quality in which the occurrence of defective coloring areas is suppressed by virtue of the inclusion of the electrochromic sheet.

[0115] In this embodiment, sunglasses 100 are shown as an example of eyeglasses, but the present invention is not limited to this. Lenses 110 may be applied to, for example, goggles that protect the eyes from wind, rain, dust, chemicals, etc. Alternatively, lenses 110 may be applied to a wearable device, such as smart glasses, that is worn on the user's head with lenses 110 positioned in front of the user's eyes.

[0116] 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.

[0117] 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. [Example]

[0118] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0119] In the examples, EC sheets with different configurations were prepared as follows, and AC impedance measurements were performed to determine the impedance per unit area. Furthermore, the color development speed and memory properties of each prepared EC sheet were evaluated. In the following explanation, the symbols used in the above-described embodiments will be used as appropriate to explain the configuration.

[0120] [Example 1] (Electrolyte layer manufacturing) The following binder resin 1, binder resin 2, and ionic liquid were mixed in a mass ratio of 23:7:70, and a photopolymerization initiator was further added in an amount of 0.5 mass % relative to the total amount of binder resins 1 and 2 to prepare an electrolyte solution. Binder resin 1: urethane acrylate (product name: UXF4002, manufactured by Nippon Kayaku Co., Ltd.) Binder resin 2: Crosslinked polymer having polymethyl methacrylate (PMMA) chains (product name: AA-6, manufactured by Toagosei Co., Ltd.) Ionic liquid 1: (EMIMFSI, ethylmethylimidazolium bisfluorosulfonimide, Kanto Chemical Co., Ltd.)

[0121] The obtained electrolyte solution was applied to the surface of a release-treated PET film (NP75C, manufactured by PANAC Corporation), and a release-treated PET film (NP75A, manufactured by PANAC Corporation) was placed on top of it, followed by UV irradiation to produce an electrolyte layer 353.

[0122] (Manufacturing of the first EC layer) On a 0.5 mm thick polycarbonate resin substrate (Polyca Ace, deflection temperature under load 140°C, manufactured by Sumitomo Bakelite Co., Ltd.), ITO was sputtered to form a first transparent electrode 31 with a thickness of approximately 100 nm. The PC resin substrate corresponds to the first substrate 11.

[0123] A solution was prepared by mixing polyethylene glycol diacrylate (PEG400DA, manufactured by Nippon Kayaku Co., Ltd.), a photoinitiator (IRGACURE 184, manufactured by BASF), a compound represented by the following formula (I) (Compound I), and 2-butanone in a mass ratio of (57:3:140:800).

[0124] [ka] (wherein Me represents a methyl group)

[0125] The prepared solution was spin-coated on the first transparent electrode 31 to form a coating film. Next, the coating film was exposed to UV light through a predetermined exposure mask in a nitrogen atmosphere, and a first EC layer 351 containing compound I was selectively formed on the first transparent electrode 31. The first EC layer 351 had a thickness of 1 μm and was patterned.

[0126] (Manufacturing the second EC layer) On a PC resin substrate (second substrate 12) similar to the first substrate 11, ITO was sputtered to form a film, and a second transparent electrode 32 having a thickness of approximately 100 nm was formed.

[0127] 5.50 g of tin oxide sol solution (Nissan Chemical Industries, Ltd., Celnax CX-S510M), 1.00 g of ethyl cellulose (10 cp, 10% by mass, ethanol solution), 0.50 g of tin(IV) tetra(t-butoxide), and 9.05 g of terpineol were mixed and treated with an ultrasonic homogenizer for 2 minutes. The volatile components were then removed with an evaporator to obtain a paste.

[0128] The obtained paste was screen-printed on the second transparent electrode 32 to a thickness of 2 μm, dried at 80° C., and then subjected to UV ozone treatment at 90° C. for 20 minutes to form a porous tin oxide particle film.

[0129] A 1.5 mass% 2,2,3,3-tetrafluoropropanol solution of a compound represented by the following formula (II) (compound II) was spin-coated onto the tin oxide film, and annealed at 80°C for 10 minutes to form a second EC layer 352 in which compound II was supported on the tin oxide film.

[0130] [ka]

[0131] (EC sheet manufacturing) An electrolyte layer 353 was attached to the surface of the second EC layer 352. Next, a sealing material (epoxy acrylate resin ("Photolec S-WF17" manufactured by Sekisui Material Solutions Co., Ltd.) was applied using a dispenser to a position surrounding the periphery of the side surface of the second EC layer 352.

[0132] Thereafter, the first EC layer 351 of the first substrate 11 was attached to the electrolyte layer 353, and pressed for 60 seconds to spread the sealing material, thereby covering the side surfaces of the first EC layer 351 and the second EC layer 352 with the sealing material. The obtained laminate was irradiated with ultraviolet light (3 J / cm 2) (pre-curing), and then heat curing treatment (main curing) was carried out at 100°C for 1 hour to form sealed portions, thereby producing the EC sheet of Example 1.

[0133] [Examples 2 to 5, Comparative Examples 1 to 3] The EC sheets of Examples 2 to 5 and Comparative Examples 1 to 3 were produced in the same manner as Example 1, except that the thickness of the transparent electrode, the thickness of the first EC layer 351, and the pressing time during bonding were set to the conditions shown in Table 2.

[0134] [Table 1]

[0135] The following measurements were carried out on each of the obtained EC sheets.

[0136] (AC impedance measurement conditions) Applied voltage: 0V Amplitude: 10mV Frequency response: 0.1Hz to 1MHz Measurement temperature: 25℃

[0137] A Nyquist diagram was created from the measurement results, and the following (1) to (3) were obtained. (1): The horizontal axis of the Nyquist diagram and the graph of the Nyquist diagram, 0 Ω / cm 2 More than 8.0Ω / cm 2 The first intersection value in the following range (2): Imaginary component is 7.0 Ω / cm 2 More than 14.0Ω / cm 2 The slope of the approximate line when the graph is approximated as a straight line in the following range: (3): A value (Ω / cm 2 ) = [value of the second intersection point between the approximation line and the horizontal axis] - [value of the first intersection point]

[0138] (Evaluation 1: Color development speed confirmation conditions) A voltage was applied to each EC sheet under the following conditions, and then the luminous transmittance at D65-2° was measured. EC sheets with a measured transmittance of less than 20% were rated as passing, and EC sheets with a measured transmittance of 20% or more were rated as failing. Applied voltage: 1.6V Application time: 15 seconds Measurement temperature: 25℃

[0139] (Evaluation 2: Memory verification conditions) For EC sheets whose luminous transmittance had reached 10% due to the application of voltage, the applied voltage was set to 0 V (open), and the sheets were left at 25°C for 45 minutes. The luminous transmittance of the EC sheets after being left was measured, and the rate of change in luminous transmittance was calculated using the following formula. EC sheets whose measured rate of change was less than 20% were deemed to have passed, and EC sheets whose measured rate of change was 20% or more were deemed to have failed. Change rate (%) = [visual transmittance after storage] - [visual transmittance before storage]

[0140] Figure 7 shows the Nyquist diagram of each EC sheet. The evaluation results for each EC sheet are shown in Table 2.

[0141] [Table 2]

[0142] As a result of the evaluation, (1) was 1.0Ω / cm 2 More than 8.0Ω / cm 2 The following are the values: (2) 25 or less, (3) 5.0 Ω / cm 2 In the following Examples 1 to 5, all of the evaluations 1 (color development speed) were good. Furthermore, the value of (3) was 0 Ω / cm 2 More than 5.0Ω / cm 2 It was confirmed that the following Examples 1 to 4 also had good memory properties.

[0143] On the other hand, it was confirmed that the color development speed was slow in Comparative Examples 1 to 3, which did not satisfy the requirements of the present invention in any of (1), (2), and (3).

[0144] From the above, it has been confirmed that the present invention is useful. [Explanation of symbols]

[0145] 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, 311, 312, 321, 322...transparent electrode layer, 331...first frame body, 331x, 341x...other end, 332...first extraction portion, 341...second frame body, 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; 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, The electrochromic element includes a first transparent electrode provided on the first substrate side; a second transparent electrode provided on the second substrate; an electrochromic layer that is sandwiched between the first transparent electrode and the second transparent electrode, that is disposed in the coloring region, and that is colored by application of a voltage; When the impedance per unit area of ​​the electrochromic sheet is measured at a response frequency range of 0.1 Hz to 1 MHz under conditions of an applied voltage of 0 V and an amplitude of 10 mV, the Nyquist diagram obtained from the measurement results satisfies the following requirements (1) to (3): (1) The horizontal axis of the Nyquist diagram and the graph of the Nyquist diagram are in a relationship of 0 Ω / cm ２ 8.0Ω / cm or more ２ The first intersection point in the following range is 1.0 Ω / cm ２ 8.0Ω / cm or more ２ Included in the following range: (2) Imaginary component is 7.0 Ω / cm ２ 14.0Ω / cm or more ２ In the following range, when the graph is approximated as a straight line, the gradient of the approximate line is 25 or less. (3) The following A value is 5.0 Ω / cm ２ The following is the result. A value = [value at the second intersection point between the approximation line and the horizontal axis] - [value at the first intersection point]

2. The A value is 0 Ω / cm ２ 5.0Ω / cm or more ２ 2. The electrochromic sheet according to claim 1, wherein:

3. a first auxiliary electrode electrically connected to the first transparent electrode; a second auxiliary electrode electrically connected to the second transparent electrode; 3. The electrochromic sheet according to claim 1, wherein the first auxiliary electrode and the second auxiliary electrode are spaced apart in the circumferential direction of the colored region and are disposed around the colored region.

4. The electrochromic layer includes a first electrochromic layer laminated on the first transparent electrode; a second electrochromic layer laminated on the second transparent electrode; an electrolyte layer filled between the first electrochromic layer and the second electrochromic layer; the first electrochromic layer contains a material that exhibits color through an oxidation reaction; 3. The electrochromic sheet according to claim 1, wherein the second electrochromic layer contains a material that exhibits coloration through a reduction reaction.

5. The electrochromic sheet according to claim 1 or 2; and a lens material on which the electrochromic sheet is laminated.

6. an electrochromic part obtained by cutting the electrochromic sheet according to claim 1 or 2; and a lens body on which the electrochromic portion is laminated.

7. The eyeglass lens according to claim 6 , a frame for holding the eyeglass lenses; The eyeglass lenses are electrically connected to the frame.

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