KR20230133553A - Electrochromic device and preparation method thereof - Google Patents

Abstract

The embodiment relates to an electrochromic device that exhibits excellent light transmission variable function based on the electrochromic principle, wherein the electrochromic device includes a first electrode layer, a first color change layer, an electrolyte layer, a second color change layer, and a second electrode layer. It includes a variable light transmission structure, and the first color-changing layer or the second color-changing layer includes a color-changing material containing nickel oxide.

Description

Electrochromic device and manufacturing method thereof {ELECTROCHROMIC DEVICE AND PREPARATION METHOD THEREOF}

The embodiment relates to an electrochromic device that exhibits excellent light transmission variable function based on the electrochromic principle and a method of manufacturing the same.

Recently, as interest in environmental protection has increased, interest in technologies that improve energy efficiency has also increased. For example, research and development on technologies such as smart windows and energy harvesting are being actively conducted. The smart window refers to an active control technology that can improve energy efficiency and provide a comfortable environment to users by adjusting the degree of penetration of light coming from the outside, and is a basic technology that can be commonly applied to various industrial fields. These smart windows include electrochromic elements in which electrochemical oxidation or reduction reactions occur in response to applied power, resulting in electrochromic changes.

Currently, glass-type smart windows with electrochromic elements applied between multiple sheets of glass are commonly used as smart windows, but the manufacturing process is complicated and the product price is very expensive because it must be manufactured to the size of the window to be installed. Subsequently, it is difficult to commercialize it. In addition, the electrochromic elements included in smart windows are limited in the colors that can be realized, so there are limits to their application to residential building windows. In other words, Prussian blue was mainly used as a discoloring material for electrochromic devices, but it mainly expressed only blue and did not correspond to the implementation of gray or black colors preferred in residential building windows.

Accordingly, electrochromic devices capable of implementing gray or black colors are being developed, but due to low ionic conductivity, they do not exhibit the required level of light transmission variable efficiency, and it is difficult to secure the flexibility of electrochromic devices due to limitations in the manufacturing process. This is the situation.

Korean Patent No. 1862200 (May 23, 2018)

The embodiment aims to provide an electrochromic device that has high ionic conductivity, has excellent light transmission variable efficiency, and can display preferred colors in residential building windows and a method of manufacturing the same.

According to an embodiment to solve the above problem, it includes a light transmission variable structure including a first electrode layer, a first color change layer, an electrolyte layer, a second color change layer, and a second electrode layer, and the first color change layer or the second electrode layer. 2. Provides an electrochromic device in which the color-changing layer includes a color-changing material containing nickel oxide, and the content of nickel oxide expressed as Ni ₃ O ₄ contained in the nickel oxide is 65% by weight or more based on the total weight of the nickel oxide. do.

According to another embodiment, (1) preparing nickel oxide; (2) preparing a gel type electrolyte; (3) manufacturing a lower plate including a first electrode layer and an upper plate including a second electrode layer by coating electrode materials on the first and second substrates, respectively; (4) forming a first discoloration layer by coating a first discoloration material composition on the first electrode layer; (5) forming a second discoloration layer by coating a second discoloration material composition on the second electrode layer; (6) forming an electrolyte layer between the first discoloring layer and the second discoloring layer; and (7) manufacturing a light transmission variable structure by combining the lower plate and the upper plate so that the first electrode layer, the first discoloration layer, the electrolyte layer, the second discoloration layer, and the second electrode layer are stacked in that order. wherein the first discoloring material composition or the second discoloring material composition includes a discoloring material containing nickel oxide prepared in step (1), and oxidation represented by Ni ₃ O ₄ contained in the nickel oxide. A method for manufacturing an electrochromic device having a nickel content of 65% by weight or more based on the total weight of the nickel oxide is provided.

The electrochromic device according to the embodiment can exhibit high ionic conductivity because it includes a first and/or second color changing layer into which nickel oxide of a specific composition is introduced, and can display a gray or black color at the maximum coloration state. Therefore, the electrochromic device according to the embodiment can be efficiently applied not only to commercial building windows but also to residential building windows.

In addition, according to an embodiment, since the first and/or second color changing layer included in the electrochromic device is manufactured through wet coating (sol-gel reaction) performed at a relatively low temperature, it is possible to apply a film substrate vulnerable to high temperatures, and this allows As a result, the flexibility of the electrochromic device can be secured. Therefore, the electrochromic device according to the embodiment can be conveniently constructed through a process of cutting and attaching to windows of various sizes and shapes, and can be manufactured in roll form, so storage and transportability can be excellent.

Figure 1 schematically shows a cross section of an electrochromic device according to an embodiment.
Figure 2 schematically shows a cross section of an electrochromic device according to another embodiment.
Figure 3 schematically shows a cross section of an electrochromic device according to another embodiment.
Figure 4 schematically shows a cross section of an electrochromic device according to another embodiment.
Figure 5 schematically shows the manufacturing process of an electrochromic device according to one embodiment.

Hereinafter, the invention will be described through implementation examples. Here, the embodiment is not limited to the content disclosed below and may be modified into various forms as long as the gist of the invention is not changed.

In this specification, the description that one component is formed above/below another component, or is connected or combined with each other, includes all those formed, connected, or combined directly between these components or indirectly through another component. . Additionally, it should be understood that the standards for the top/bottom of each component may vary depending on the direction in which the object is observed.

In this specification, the term "include" is intended to specify specific characteristics, areas, steps, processes, elements and/or components, and unless specifically stated to the contrary, other characteristics, areas, steps, processes, elements and /or does not exclude the presence or addition of ingredients.

In this specification, singular expressions are interpreted to include singular or plural as interpreted in context, unless otherwise specified.

All numbers and expressions indicating the amounts of components, reaction conditions, etc. described in this specification should be understood as being modified by the term “about” in all cases unless otherwise specified.

In this specification, terms such as first and second are used to describe various components, and the components should not be limited by the terms. The above terms are used for the purpose of distinguishing one component from another.

An embodiment provides an electrochromic device that can implement black color while exhibiting excellent light transmission variable function based on the electrochromic principle. This will be described in detail with reference to the drawings as follows.

electrochromic device

The electrochromic device 100 according to the embodiment includes a variable light transmission structure whose light transmittance reversibly changes when a predetermined voltage is applied. The variable light transmission structure 110 includes a first electrode layer 111, a first discoloration layer 112, an electrolyte layer 113, a second discoloration layer 114, and a second electrode layer 115 (FIG. 1 reference).

Specifically, the light transmission variable structure 110 includes a first electrode layer 111, a first discoloration layer 112, an electrolyte layer 113, a second discoloration layer 114, and a second electrode layer 115 in order. It may be a layered structure. When a voltage is applied to the first electrode layer 111 and the second electrode layer 115, the light transmission variable structure 110 is formed from the second discoloration layer 114 through the electrolyte layer 113. The overall light transmittance increases and decreases due to specific ions or electrons moving through the discoloration layer 112. Each layer included in this variable light transmission structure 110 will be described in detail as follows.

First electrode layer and second electrode layer

The first electrode layer 111 and the second electrode layer 115 included in the variable light transmission structure 110 according to the embodiment may each include a transparent electrode or a reflective electrode. In one embodiment, one of the first electrode layer 111 and the second electrode layer 115 may be a transparent electrode, and the other may be a reflective electrode. In another embodiment, both the first electrode layer 111 and the second electrode layer 115 may be transparent electrodes.

The transparent electrode may include a material that has high light transmittance and low sheet resistance while being penetration resistant, and may have an electrode plate shape.

For example, the transparent electrode is selected from the group consisting of indium-tin oxide (ITO), zinc oxide (ZnO, Zinc oxide), indium-zinc oxide (IZO), and combinations thereof. Can contain selected materials.

The reflective electrode is, for example, a group consisting of silver (Ag), aluminum (Al), copper (Cu), molybdenum (Mo), gold (Au), tungsten (W), chromium (Cr), and combinations thereof. It can include materials selected from .

The thickness of each of the first electrode layer 111 and the second electrode layer 115 may be 100 to 500 nm, 100 to 400 nm, 100 to 300 nm, or 150 to 250 nm, but is not limited thereto.

Specifically, each of the first electrode layer 111 and the second electrode layer 115 may be a transparent electrode and may include indium-tin oxide. More specifically, each of the first electrode layer 111 and the second electrode layer 115 may be a transparent electrode containing indium oxide:tin oxide in a weight ratio of 70:30 to 98:2, or 80:20 to 97:3. there is.

The surface resistance of each of the first electrode layer 111 and the second electrode layer 115 may be 5 to 100 Ω/sq, 5 to 80 Ω/sq, 5 to 70 Ω/sq, or 5 to 50 Ω/sq. However, it is not limited to this.

First discoloring layer and second discoloring layer

The first color change layer 112 and the second color change layer 114 included in the variable light transmission structure 110 according to the embodiment apply a voltage between the first electrode layer 111 and the second electrode layer 115. It is a layer whose light transmittance changes when applied, and is a layer that provides light transmittance variability to electrochromic devices.

The first color-changing layer 112 and the second color-changing layer 114 may include color-changing materials having complementary color development characteristics. The complementary color development characteristics mean that the types of color reactions produced by the color changing materials are different. For example, if an oxidative color change material is used in the first color change layer 112, a reductive color change material may be used in the second color change layer 114, and if a reductive color change material is used in the first color change layer 112. An oxidative discoloring material may be used in the second discoloring layer 114.

The oxidative discoloration material refers to a material that changes color when an oxidation reaction occurs, and the reductive discoloration material refers to a material that changes color when a reduction reaction occurs. That is, when an oxidation reaction occurs in the color change layer to which the oxidative color change material is applied, a coloring reaction occurs, and when a reduction reaction occurs, a decolorization reaction occurs. Additionally, when a reduction reaction occurs in the discoloring layer to which the reductive discoloring material is applied, a coloring reaction occurs, and when an oxidation reaction occurs, a decolorization reaction occurs. By using color-changing materials with complementary color development characteristics in each color-changing layer, coloring or development of color can occur simultaneously in both color-changing layers.

The reductive discoloring material specifically includes titanium oxide (TiO), vanadium oxide (V ₂ O ₅ ), niobium pentoxide (Nb ₂ O ₅ ), chromium oxide (Cr ₂ O ₃ ), manganese oxide (MnO ₂ ), and iron oxide. (FeO ₂ ), rhodium oxide (RhO ₂ ), tantalum oxide (Ta ₂ O ₅ ), iridium oxide (IrO ₂ ), tungsten oxide, viologen, and combinations thereof. It may be possible, but it is not limited to this.

The oxidative discoloration material specifically includes nickel oxide, manganese oxide, cobalt oxide, iridium-magnesium oxide, nickel-magnesium oxide, It may be selected from the group consisting of titanium-vanadium oxide and combinations thereof, but is not limited thereto.

According to one embodiment, the first color changing layer 112 or the second color changing layer 114 includes a color changing material including nickel oxide. The nickel oxide included in the discoloring material is nickel oxide having a nickel oxide content expressed as Ni ₃ O ₄ of 65% by weight or more based on the total weight of the nickel oxide. As nickel oxide having this composition is included as a discoloring material, the first discoloring layer 112 or the second discoloring layer 114 may exhibit a gray or black color during a coloring reaction.

Specifically, the nickel oxide has a content of nickel oxide expressed as Ni ₃ O ₄ of 65 to 99.9% by weight, 75 to 99.9% by weight, 80 to 99.9% by weight, 85 to 99.9% by weight, 90% by weight, based on the total weight of nickel oxide. It may be from 99.9% by weight, or from 95 to 99.8% by weight, but is not limited thereto. When the content of Ni ₃ O ₄ contained in the nickel oxide is within the above range, substitution with lithium ions present in the electrolyte layer 113 is efficiently achieved, resulting in an electrochromic device ( 100) can be implemented.

According to one embodiment, in addition to nickel oxide represented by Ni ₃ O ₄ , the nickel oxide is represented by nickel oxide represented by NiO, nickel oxide represented by NiO ₂ , nickel oxide represented by Ni ₂ O ₃ , and Ni ₂ O. It may further include two or more types of nickel oxide selected from the group consisting of nickel oxide represented by Ni ₃ O, and nickel oxide represented by Ni ₄ O.

According to another embodiment, in addition to nickel oxide represented by Ni ₃ O ₄ , the nickel oxide is represented by nickel oxide represented by NiO, nickel oxide represented by NiO ₂ , nickel oxide represented by Ni ₂ O ₃ , and Ni ₂ O. It may further include three or more, four or more, or five or more types of nickel oxide selected from the group consisting of nickel oxide represented by Ni ₃ O and nickel oxide represented by Ni ₄ O.

For example, the nickel oxide may include 0.05 to 1% by weight, 0.1 to 0.7% by weight, 0.2 to 0.5% by weight, or 0.3 to 0.45% by weight of nickel oxide expressed as NiO ₂ based on the total weight of the nickel oxide. However, it is not limited to this.

The nickel oxide may include 0.005 to 0.05% by weight, 0.006 to 0.03% by weight, 0.007 to 0.015% by weight, or 0.008 to 0.012% by weight of nickel oxide, expressed as NiO, based on the total weight of the nickel oxide. It is not limited.

The nickel oxide may include 0.005 to 0.05% by weight, 0.006 to 0.03% by weight, 0.007 to 0.015% by weight, or 0.008 to 0.012% by weight of nickel oxide represented by Ni ₂ O ₃ based on the total weight of the nickel oxide. However, it is not limited to this.

The nickel oxide may include 0.005 to 0.05% by weight, 0.006 to 0.03% by weight, 0.007 to 0.015% by weight, or 0.008 to 0.012% by weight of nickel oxide, expressed as Ni ₂ O, based on the total weight of the nickel oxide. , but is not limited to this.

The nickel oxide may include 0.005 to 0.05 wt%, 0.006 to 0.03 wt%, 0.007 to 0.015 wt%, or 0.008 to 0.012 wt% of nickel oxide, expressed as Ni ₃ O, based on the total weight of the nickel oxide. , but is not limited to this.

The nickel oxide may include 0.005 to 0.05 wt%, 0.006 to 0.03 wt%, 0.007 to 0.015 wt%, or 0.008 to 0.012 wt% of nickel oxide, expressed as Ni ₄ O, based on the total weight of the nickel oxide. , but is not limited to this.

According to another embodiment, the nickel oxide is 98 to 99.9% by weight of nickel oxide represented by Ni ₃ O ₄ based on the total weight of the nickel oxide; 0.05 to 1% by weight of nickel oxide, represented by NiO ₂ ; 0.005 to 0.05% by weight of nickel oxide, denoted NiO; 0.005 to 0.05% by weight of nickel oxide represented by Ni ₂ O ₃ ; 0.005 to 0.05% by weight of nickel oxide, expressed as Ni ₂ O; 0.005 to 0.05% by weight of nickel oxide, expressed as Ni ₃ O; and 0.005 to 0.05% by weight of nickel oxide represented by Ni ₄ O, but is not limited thereto. By including nickel oxide having this composition as a color change material, an electrochromic device 100 that exhibits a black color and has a wide color change range due to an efficient color reaction of the first color change layer 112 or the second color change layer 114 can be implemented. You can.

According to one embodiment, the average particle diameter (D ₅₀ ) of the nickel oxide may be 20 to 80 nm, 25 to 70 nm, 26 to 60 nm, 27 to 55 nm, or 28 to 50 nm, but is not limited thereto. no. When the average particle diameter (D ₅₀ ) of the nickel oxide is within the above range, the electrochromic device 100 can be implemented that has a wide discoloration section and can exhibit excellent light transmission variable function even when repeatedly driven for a long time.

Nickel oxide may be included in an amount of 15 to 95% by weight in the first discoloration layer 112 or the second discoloration layer 114, but is not limited thereto. Specifically, the content of nickel oxide occupying the first color change layer 112 or the second color change layer 114 is 20 to 94.5% by weight, 45 to 92% by weight, and 60 to 91% by weight, based on the total weight of each color change layer. It may be 70 to 85% by weight, or 73 to 84% by weight, but is not limited thereto. When the content of nickel oxide contained in each of the first discoloring layer 112 or the second discoloring layer 114 is within the above range, an efficient coloring reaction of the first discoloring layer 112 or the second discoloring layer 114 occurs. As a result, it is possible to implement an electrochromic device 100 that displays black color and has a wide discoloration range.

According to one embodiment, the first discoloration layer 112 may be an oxidation discoloration layer containing nickel oxide as an oxidative discoloration material, and the second discoloration layer 114 may be a reduction discoloration layer containing the reductive discoloration material. You can. Alternatively, the first discoloration layer 112 may be a reductive discoloration layer containing the reductive discoloration material, and the second discoloration layer 114 may be an oxidation discoloration layer containing the nickel oxide as an oxidative discoloration material.

Meanwhile, each of the first discoloring layer 112 and the second discoloring layer 114 may further include a polymer resin. The polymer resin is, for example, urethane-acrylic resin, silicone-based resin, acrylic resin, ester-based resin, epoxy-based resin, phenol-based resin, polyurethane-based resin, polyimide-based resin, ethylene vinyl acetate-based resin, phosphoric acid-based resin, or It may be a carboxylic resin, etc.

The thickness of each of the first color changing layer 112 and the second color changing layer 114 may be 100 to 1,000 nm, 250 to 900 nm, 400 to 800 nm, or 650 to 700 nm, but is not limited thereto. . When the thickness of each of the first color change layer 112 and the second color change layer 114 is within the above range, thinning and flexibility of the electrochromic device 100 are secured, and excellent light transmission variable function is achieved even when repetitive driving is performed. can be implemented.

The thickness ratio of the first discoloring layer 112 and the second discoloring layer 114 may be 40:60 to 80:20, 45:55 to 75:25, or 50:50 to 70:30, but is limited thereto. It doesn't work. When the thickness ratio of the first color change layer 112 and the second color change layer 114 is within the above range, the width of the color change section (color change section) that becomes transparent and dark can be wider, and the color change time can be shorter. there is.

electrolyte layer

The electrolyte layer 113 included in the variable light transmission structure 110 according to the embodiment is a layer that serves as an ion movement path between the first discoloration layer 112 and the second discoloration layer 114.

This electrolyte layer 113 may include a halogenated organoborane compound. The halogenated organoborane compound may be a compound containing one or more boron atoms linked to a carbon atom. Specifically, the halogenated organoborane compound may be a compound having 5 to 30 carbon atoms (specifically 10 to 20, or 15 to 25) and 1 to 3 boron atoms connected to a carbon atom.

For example, the halogenated organoborane compound may have one or more aromatic, alicyclic, or aliphatic hydrocarbon groups. The number of each hydrocarbon group may be 1 to 5. Additionally, the number of carbon atoms in each hydrocarbon group may be 3 to 15, or 6 to 10. Meanwhile, at least one hydrogen atom of each hydrocarbon group may be substituted with halogen. The halogen may be a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, or a combination thereof, and specifically may be a fluorine atom.

For example, the halogenated organoborane compound may be a perfluorinated organoborane compound in which all hydrogen atoms of its hydrocarbon groups are replaced with fluorine atoms. For example, the halogenated organoborane compound may have one or more perfluoroaryl groups having 6 to 10 carbon atoms, and in this case, the perfluoroaryl group may be a perfluorophenyl group.

Specifically, the halogenated organoborane compound may include a compound represented by the following formula (1).

[Formula 1]

In Formula 1, n is the number of perfluorophenyl groups and is an integer of 1 to 3, and R is hydrogen or a perfluoroalkyl group having 1 to 12 carbon atoms.

Meanwhile, the electrolyte layer 113 may further include hydrogen ions or group 1 element ions. For example, the electrolyte layer 113 may further include a metal salt.

Additionally, the electrolyte layer 113 may further include a polymer resin. The polymer resin may be selected from acrylic resin, epoxy resin, silicone resin, polyimide resin, polyurethane resin, or a combination thereof. The acrylic resin may be a thermosetting acrylic resin or a photocurable acrylic resin, and the polyurethane resin may be a thermosetting polyurethane resin, a photocurable polyurethane resin, or a water-based polyurethane resin.

Additionally, the electrolyte layer 113 may further include a photoinitiator. The photoinitiator may be selected from acetophenone-based compounds, benzophenone-based compounds, thioxanthone-based compounds, benzoin-based compounds, triazine-based compounds, oxime-based compounds, or combinations thereof. Specifically, the photoinitiator is 2,2'-diethoxyacetophenone, 2,2'-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p-t-butyltrichloroacetophenone, p-t -Butyldichloroacetophenone, 4-chloroacetophenone, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4- Diisopropyl thioxanthone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis ( Trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-methoxynaph) Tyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p- It may be tolyl)-4,6-bis(trichloromethyl)-s-triazine, or 2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione, etc. , but is not limited to this.

The electrolyte layer 113 may include 5 to 750 parts by weight of the metal salt, 0.01 to 50 parts by weight of the halogenated organoborane compound, and 0.01 to 100 parts by weight of the photoinitiator, based on 1000 parts by weight of the polymer resin.

For example, the electrolyte layer 113 includes 1000 parts by weight of acrylic resin, based on the non-volatile component content; 5 to 50 parts by weight of metal salt; 0.01 to 3 parts by weight of a halogenated organoborane compound; and 1 to 50 parts by weight of a photoinitiator.

The number average molecular weight of the acrylic resin may be 100 to 1,000,000. Additionally, the viscosity of the acrylic resin may be 1,000 to 10,000 mPa·s at room temperature, and specifically 3,000 to 9,000 mPa·s.

The glass transition temperature (Tg) of the acrylic resin may be -90 to -10 °C, specifically -70 to -30 °C.

Additionally, the visible light transmittance of the acrylic resin may be 70% or more, 80% or more, or 90% or more.

Monomer units constituting the acrylic resin include, for example, 2-ethylhexyl acrylate, methyl (meth)acrylate, butyl (meth)acrylate, acrylamide, methylacrylamide, hydroxyethyl (meth)acrylate, It may be (meth)acrylic acid, itaconic acid, styrene, other monomers having a mono- or bi-functional acrylate group, or a combination thereof. It may be desirable for such acrylic resin to contain a carboxyl group in the side chain in terms of providing adhesion and compatibility with additives, etc.

The metal salt may include a lithium salt compound. The lithium salt compound is LiF, LiCl, LiBr, LiI, LiClO ₄ , LiClO ₃ , LiAsF ₆ , LiSbF ₆ , LiAl0 4, LiAlCl _{4 ,} LiNO ₃ , LiN(CN) ₂ , LiPF ₆ , Li(CF ₃ ) ₂ PF ₄ , Li(CF ₃ ) ₃ PF ₃ , Li(CF ₃ ) ₄ PF ₂ , Li(CF ₃ ) ₅ PF, Li(CF ₃ ) ₆ P, LiSO ₃ CF ₃ , LiSO ₃ C ₄ F ₉ , LiSO ₃ (CF ₂ ) ₇ CF ₃ , LiN(SO ₂ CF ₃ ) ₂ , LiOC(CF ₃ ) ₂ CF ₂ CF ₃ , LiCO ₂ CF ₃ , LiCO ₂ CH ₃ , LiSCN, LiB(C ₂ O ₄ ) ₂ , LiBF ₂ (C ₂ O ₄ ), LiBF ₄ , LIBOB (lithium bis(oxalato)borate), LiDODFP (lithium difluorobis(oxalato)phosphate), LiFSI (lithium bis(fluorosulfonyl)imide ), or LiTFSI (lithium bis(trifluoromethane)sulfonimide), but is not limited thereto.

Since the metal salt is generally in the form of a solid crystal, a polar solvent may be further included in the composition forming the electrolyte layer 113 to dissolve it. The polar solvent may be, for example, methyl ethyl ketone, propylene carbonate, dimethyl carbonate, ethyl methyl carbonate, ethyl propionate, methyl propionate, isopropyl alcohol, or acetone. The polar solvent may be used in an amount of 40 to 80 parts by weight, or 50 to 70 parts by weight, based on 100 parts by weight of the metal salt.

The halogenated organoborane compound may be added to the composition forming the electrolyte layer 113 in a solution state dissolved in a solvent. The solvent for dissolving the halogenated organoborane compound may be, for example, a non-polar solvent, and specifically may be toluene, xylene, hexane, or isopropyl alcohol.

The electrolyte layer 113 may have an ionic conductivity of 10 ^-3 mS/cm or more. Specifically, the ion conductivity of the electrolyte layer 113 may be 10 ^-3 to 10 ³ mS/cm, or 10 ^-3 to 10 ² mS/cm. When the ionic conductivity of the electrolyte layer 113 is within the above range, the desired light transmission variable function can be implemented, and the electrochromic device 100 can be more advantageous in terms of reliability at high temperatures while securing flexibility.

The electrolyte layer 113 may have an adhesive force of 3 g/cm or more. Specifically, the adhesive force of the electrolyte layer 113 may be 3 to 300 g/cm, 3 to 200 g/cm, or 3 to 100 g/cm. When the adhesive force of the electrolyte layer 113 is within the above range, it is well attached to the target substrate (e.g., the first color change layer 112 and the second color change layer 114), thereby improving the performance of the electrochromic device 100. It can be expressed smoothly.

The thickness of the electrolyte layer 113 may be 30 to 200 ㎛, 50 to 150 ㎛, 70 to 130 ㎛, or 80 to 120 ㎛. When the thickness of the electrolyte layer 113 is within the above range, durability is provided to the electrochromic device 100 and the ion movement path between the first color change layer 112 and the second color change layer 114 is maintained to an appropriate length. By securing the required level of light transmission variable function, it is possible to implement.

Meanwhile, the electrochromic device 100 according to the embodiment may further include a first base layer 120 and a second base layer 130 (see FIG. 1), which will be described in detail as follows.

First substrate layer and second substrate layer

The first base layer 120 and the second base layer 130, which are further included in the electrochromic device 100 according to the embodiment, are provided on the upper and lower portions of the light transmission variable structure 110, respectively, and form the electrochromic device 100. This layer serves to increase durability. The first base layer 120 and the second base layer 130 may each include a polymer resin selected from the group consisting of polyester resin, acrylic resin, polyolefin resin, and combinations thereof.

For example, each of the first base layer 120 and the second base layer 130 may include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polycarbonate (PC), but is limited thereto. It doesn't work. Since the first base layer 120 and the second base layer 130 contain the polymer resin, an electrochromic device 100 having excellent durability and flexibility can be implemented.

Each of the first base layer 120 and the second base layer 130 may exhibit a light transmittance of 80% or more for light with a wavelength of 550 nm. Specifically, it may exhibit a light transmittance of 85% or more, or 90% or more, respectively, for light with a wavelength of 550 nm. Additionally, each of the first base layer 120 and the second base layer 130 may have a haze of 2.0% or less, 1.8% or less, or 1.5% or less. When the light transmittance and haze of the first base layer 120 and the second base layer 130 are within the above range, transparency of the electrochromic device 100 can be secured.

The thickness of each of the first base layer 120 and the second base layer 130 may be 10 to 300 ㎛, 50 to 280 ㎛, 70 to 260 ㎛, or 100 to 250 ㎛, but is not limited thereto. . When the thickness of each of the first base layer 120 and the second base layer 130 is within the above range, an electrochromic device 100 that is thin, light, and flexible can be implemented.

In addition, the electrochromic device 100 according to the embodiment may further include a barrier layer 140 that serves to prevent impurities, including moisture or gas, from penetrating into the light transmission variable structure 110 from the outside (Figure 2). The barrier layer 140 may be provided between the variable light transmission structure 110 and the first base layer 120 and between the variable light transmission structure 110 and the second base layer 130, respectively.

The barrier layer 140 is a metal barrier layer including one selected from the group consisting of metal oxide, metal nitride, metal oxynitride, metalloid oxide, metalloid nitride, metallurgical oxynitride, or acrylic resin, It may include a resin barrier layer containing one selected from the group consisting of epoxy resin, silicone resin, polyimide resin, polyurethane resin, and combinations thereof. Specifically, the barrier layer 140 may have a structure in which the metal barrier layer is stacked in two layers, or in a structure in which the resin barrier layer is combined with two metal barrier layers to form a three-layer structure.

The thickness of the barrier layer 140 may be 20 to 200 nm, 30 to 150 nm, 40 to 120 nm, or 40 to 100 nm, but is not limited thereto.

In addition, the electrochromic device 100 according to the embodiment may further include a primer layer 150 that serves to improve the refractive index while increasing the adhesion between each base layer 120 and 130 and the barrier layer 140. (See Figure 3). The primer layer 150 may be provided between the first base layer 120 and the barrier layer 140 and between the second base layer 130 and the barrier layer 140, respectively.

The primer layer 150 has a one-layer primer layer structure containing a resin selected from the group consisting of acrylic resin, polyurethane resin, silicone resin, polyimide resin, and combinations thereof, or a structure in which a plurality of primer layers are stacked. It can be.

The primer layer 150 may have a surface tension of 35 dyne/cm ² or less, or a surface tension of 30 dyne/cm ² or less. Additionally, the primer layer 150 may have an adhesion force of 3.0 gf/inch or more, or an adhesion force of 3.5 gf/inch or more.

In addition, the electrochromic device 100 according to the embodiment may further include a hard coating layer 160 that serves to protect the electrochromic device 100 (see FIG. 4). The hard coating layer 160 may be provided on the second base layer 130. At this time, in Figure 4, the hard coating layer 160 is provided on the second base layer 130, but conversely, it may be provided on the first base layer 120.

The hard coating layer 160 may include a resin selected from the group consisting of acrylic resin, silicone resin, polyurethane resin, epoxy resin, polyimide resin, and combinations thereof.

The thickness of the hard coating layer 160 may be 1 to 10 ㎛, 2 to 8 ㎛, 2 to 6 ㎛, or 2 to 5 ㎛, but is not limited thereto. When the thickness of the hard coating layer 160 is within the above range, an electrochromic device 100 with flexibility and excellent constructability can be implemented.

In addition, the electrochromic device 100 according to the embodiment further includes an adhesive layer 170 for construction and a release film layer 180 that protects the electrochromic device 100 from external moisture or impurities while increasing storage and mobility. It may include (see Figure 4).

The adhesive layer 170 may include a resin selected from the group consisting of acrylic resin, silicone resin, polyurethane resin, epoxy resin, polyimide resin, and combinations thereof. Specifically, the adhesive layer 170 may include acrylic resin in consideration of optical properties and durability.

The initial adhesive force of the adhesive layer 170 may be 0.5 to 8.0 N/inch, 1.0 to 7.0 N/inch, or 2.0 to 6.0 N/inch, but is not limited thereto.

The release film layer 180 may include a material selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), and combinations thereof.

The thickness of the release film layer 180 may be 10 to 100 ㎛, 10 to 80 ㎛, 10 to 50 ㎛, or 12 to 50 ㎛, but is not limited thereto.

The peeling force of the release film layer 180 may be 50 gf/inch or less. Specifically, the peeling force of the release film layer 180 may be 3 to 50 gf/inch, or 10 to 50 gf/inch, but is not limited thereto.

The electrochromic device 100 according to this embodiment may exhibit a black color because the above-described first color change layer 112 or the second color change layer 114 contains nickel oxide of a specific composition as a color change material.

Specifically, when the electrochromic device 100 according to one embodiment is changed to the maximum coloring state, the R coordinate value in RGB color coordinates is 0 to 0.125, 0 to 0.120, or 0 to 0.110; the G coordinate value is 0 to 0.156, 0 to 0.135, or 0 to 0.110; The color of the section where the B coordinate value is 0 to 0.188, 0 to 0.165, or 0 to 0.125 can be displayed. As the electrochromic device 100 according to the embodiment displays black color using these coordinate values, it can be efficiently applied not only to commercial building windows but also to residential building windows.

The electrochromic device 100 according to another embodiment may have an ionic conductivity of 1×10 ^-6 mS/cm or more measured at 25°C. Specifically, the ion conductivity of the electrochromic device 100 is 1×10 ^-6 to 1×10 ^-1 mS/cm, 1×10 ^-5 to 5×10 ^-1 mS/cm, or 1×10 ^-4 . It may be from 1×10 ^-2 mS/cm, but is not limited thereto.

Meanwhile, the electrochromic device 100 according to the embodiment may have an initial transmittance of 25 to 40%, 25 to 35.5%, 25 to 35%, 25 to 33%, or 25 to 30%, as measured in the maximum coloring state. It is not limited to this.

In addition, the electrochromic device 100 according to the embodiment may have an initial transmittance of 50 to 80%, 55 to 75%, 55 to 72%, 55 to 70%, or 65 to 70%, as measured in the maximum decolorization state. It is not limited to this.

In addition, the electrochromic device 100 according to the embodiment has a difference between the initial transmittance measured in the maximum discoloration state and the initial transmittance measured in the maximum coloring state of 20 to 45%, 25 to 45%, 35 to 45%, and 40 to 45%. %, or 40 to 43 %, but is not limited thereto.

The electrochromic device 100 according to this embodiment has a fast rate of change in transmittance and can exhibit excellent light transmission variable function. For example, the electrochromic device 100 takes 80 seconds or less for the average visible light transmittance (550 nm) to reach from 65% to 10% at room temperature when applying a voltage from 1.2 V to -1.2 V, specifically. It may be within 70 seconds, or within 60 seconds.

In addition, the electrochromic device 100 according to the embodiment is not only relatively thin, but also has light and flexible characteristics, so it has excellent constructability and can be stored in a roll form, so it can also have excellent transportability.

The electrochromic device 100 according to this embodiment can be applied by simply attaching it to a general transparent window. Specifically, the electrochromic element 100 may be attached to the entire window or only to a portion of the window. Additionally, the electrochromic element 100 may also be applied to be inserted into a window.

Manufacturing method of electrochromic device

The embodiment provides a method for manufacturing the above-described electrochromic device. Specifically, according to one embodiment, the method of manufacturing the electrochromic device includes the steps of (1) manufacturing nickel oxide; (2) preparing a gel type electrolyte; (3) manufacturing a lower plate including a first electrode layer and an upper plate including a second electrode layer by coating electrode materials on the first and second substrates, respectively; (4) forming a first discoloration layer by coating a first discoloration material composition on the first electrode layer; (5) forming a second discoloration layer by coating a second discoloration material composition on the second electrode layer; (6) forming an electrolyte layer between the first discoloring layer and the second discoloring layer; and (7) manufacturing a light transmission variable structure by combining the lower plate and the upper plate so that the first electrode layer, the first discoloration layer, the electrolyte layer, the second discoloration layer, and the second electrode layer are stacked in that order. It may be included, and this will be explained with reference to FIG. 5 as follows.

Step (1) is a step of producing nickel oxide having a specific composition. According to one embodiment, step (1) may be a step of producing nickel oxide having a uniform shape, a large specific surface area, and a specific composition through high-temperature, high-pressure hydrothermal synthesis and high-temperature sintering. Specifically, step (1) includes (1-1) preparing a reactant by introducing a mixture of a nickel oxide precursor and a solvent into a high pressure reactor and reacting at 150 to 250° C. under 400 to 600 psi; and (1-2) adding the reactant to a calcination furnace and calcination at 250 to 350°C.

The nickel oxide precursor used in step (1-1) is, for example. It may be nickel acetate tetrahydrate, nickel(II) nitrate hexahydrate, etc.

The solvent used in step (1-1) may be selected from the group consisting of, for example, alcohol-based solvents, ether-based solvents, ketone-based solvents, ester-based solvents, hydrocarbon-based solvents, or combinations thereof. For example, considering the dispersibility and reactivity of the nickel oxide precursor, the solvent may be an alcohol-based solvent such as ethanol.

In step (1-1), the mixture is introduced into a high pressure reactor and heated at 150 to 250°C, specifically 170 to 240°C, under the application of 400 to 600 psi, specifically 420 to 580 psi, 450 to 550 psi, or 480 to 520 psi. , the reactant can be obtained in high yield by reacting at 180 to 230 °C, or 190 to 210 °C.

In step (1-2), the reactant is put into a sintering furnace and fired at 250 to 350°C, specifically 265 to 340°C, 275 to 320°C, or 290 to 310°C, resulting in oxidation with high density and nano-level particle size. You can get nickel.

By producing nickel oxide in step (1), in one embodiment, nickel oxide having a content of nickel oxide represented by Ni ₃ O ₄ of 65% by weight or more based on the total weight of the nickel oxide can be obtained. Specifically, nickel oxide has a content of nickel oxide expressed as Ni ₃ O ₄ of 65 to 99.9% by weight, 75 to 99.9% by weight, 80 to 99.9% by weight, 85 to 99.9% by weight, and 90 to 90% by weight, based on the total weight of nickel oxide. It may be 99.9% by weight, or 95 to 99.8% by weight, but is not limited thereto. By forming the first or second color changing layer, which will be described later, using nickel oxide having such a composition, an electrochromic device that exhibits a black color while exhibiting excellent light transmission variable function can be implemented.

Step (2) is a step of preparing a gel-type electrolyte using an electrolyte-forming composition containing the above-described halogenated organoborane compound, polymer resin, metal salt, photoinitiator, and solvent. For example, a transparent gel-type electrolyte can be prepared by stirring the reaction tank into which the electrolyte-forming composition is added at 30 to 70°C, specifically 40 to 60°C, for 30 minutes to 2 hours, specifically 30 minutes to 90 minutes. .

In step (3), the electrode material is coated on the first substrate and the second substrate to manufacture a lower plate including the first electrode layer and the first substrate layer and an upper plate including the second electrode layer and the second substrate layer, respectively. This is the step. A method of coating the electrode material on the first and second substrates may include sputtering, but is not limited thereto.

The electrode material is, for example, indium-tin oxide (ITO), zinc oxide (ZnO, Zinc oxide), indium-zinc oxide (IZO, Indium-zinc oxide), and a group consisting of combinations thereof. can be selected

For example, the first substrate and the second substrate may be materials each containing polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polycarbonate (PC).

In step (4) and step (5), the first color change material composition is coated on the first electrode layer to form a first color change layer, and the second color change material composition is coated on the second electrode layer to form a second color change material. This is the step of forming layers. Step (4) and step (5) may be performed simultaneously, step (5) may be performed after step (4), or step (4) may be performed after step (5). .

According to one embodiment, the first color change material composition or the second color change material composition includes a color change material containing nickel oxide prepared in step (1). Specifically, the first discoloration material composition or the second discoloration material composition includes the nickel oxide prepared in step (1); dispersant; Adhesion enhancer; Antioxidants; smoothing agent (leveling agent); and a solvent, but is not limited thereto.

The nickel oxide included in the first color change material composition or the second color change material composition can act as an oxidative color change material and allow the electrochromic device to display black color in the maximum color state. The content of nickel oxide may be 5 to 30% by weight, 10 to 28% by weight, 12 to 25% by weight, or 17 to 22% by weight based on the total weight of each color change material composition, but is not limited thereto.

The dispersing agent included in the first discoloring material composition or the second discoloring material composition serves to disperse nickel oxide so that it has a uniform particle size. The dispersant may be, for example, a polyacrylic dispersant, a polyethyleneimine-based dispersant, or a polyurethane-based dispersant. The content of this dispersant may be 0.1 to 5% by weight, 0.5 to 4% by weight, 0.8 to 3% by weight, or 1 to 2% by weight based on the total weight of each color change material composition, but is not limited thereto.

The adhesion enhancer included in the first discoloration material composition or the second discoloration material composition is coated on the surface of nickel oxide so that the nickel oxide is applied to the target substrate (e.g., It plays a role in ensuring good bonding to the first electrode layer or the second electrode layer. The adhesion enhancer may be, for example, a phosphoric acid-based resin (copolymer), or a carboxylic resin (copolymer). The content of this adhesion enhancer may be 0.1 to 3% by weight, 0.5 to 2.8% by weight, 1 to 2.5% by weight, or 1.5 to 2.2% by weight based on the total weight of each color change material composition, but is not limited thereto.

The antioxidant included in the first discoloration material composition or the second discoloration material composition serves to prevent oxidation of nickel oxide. The antioxidant may be, for example, a phenol-based compound, a phosphorus-based compound, a sulfur-based compound, an amine-based compound, a quinone-based compound, hydroxybenzoate, or a mixture thereof. The content of such antioxidant may be 0.1 to 2% by weight, 0.5 to 1.8% by weight, 0.7 to 1.5% by weight, or 0.9 to 1.2% by weight based on the total weight of each discoloration material composition, but is not limited thereto.

The leveling agent included in the first discoloring material composition or the second discoloring material composition serves to form a first discoloring layer or a second discoloring layer having a constant height. The leveling agent may be, for example, polyether-modified dialkylpolysiloxane, polyester-modified dialkylpolysiloxane, or a mixture thereof. The content of this leveling agent may be 0.1 to 2% by weight, 0.5 to 1.8% by weight, 0.7 to 1.5% by weight, or 0.9 to 1.2% by weight based on the total weight of each discoloration material composition, but is not limited thereto.

The solvent included in the first color change material composition or the second color change material composition serves to control the dispersibility and viscosity of each color change material composition. The solvent may be, for example, an alcohol-based solvent, an ether-based solvent, a ketone-based solvent, an ester-based solvent, a hydrocarbon-based solvent, or a mixture thereof. The content of this solvent may be 65 to 80% by weight, 68 to 78% by weight, 70 to 77% by weight, or 73 to 76% by weight based on the total weight of each color change material composition, but is not limited thereto.

According to one embodiment, the first color change material composition or the second color change material composition contains 5 to 30% by weight of nickel oxide, based on the total weight of each color change material composition; 0.1 to 5% by weight of dispersant; 0.1 to 3% by weight of adhesion enhancer; 0.1 to 2% by weight of antioxidant; 0.1 to 2% by weight of leveling agent; and 65 to 80% by weight of solvent, but is not limited thereto.

The first discoloring material composition or the second discoloring material composition containing the above components is prepared by putting the nickel oxide, the dispersant, the adhesion enhancer, and the solvent into a container and performing ball mill dispersion to prepare a dispersion. It can be manufactured through a process of diluting the dispersion by adding antioxidants, leveling agents, and additional solvents.

Through the ball mill dispersion, nickel oxide can be granulated to have a uniform nano size and a smooth surface, and by diluting it with an additional solvent, a first discoloring material composition or a second discoloring material composition with excellent dispersibility of nickel oxide is produced. You can get it. For example, the ball mill dispersion may be performed by adding a ball mill with a size of 20 to 50 nm into a container and performing the dispersion at 20 to 30° C. at a speed of 50 to 150 rpm for 20 to 30 hours. Upon passing through the ball mill dispersion, the average particle diameter (D ₅₀ ) of the nickel oxide contained in the first color change material composition or the second color change material composition is 20 to 80 nm, 25 to 70 nm, 26 to 60 nm, and 27 to 55 nm. , or 28 to 50 nm, but is not limited thereto.

According to one embodiment, the first color change material composition may include a reductive color change material to form a first color change layer, which is a reduction color change layer, and the second color change material composition may include the nickel oxide, the dispersant, and the It may be a composition that forms a second discoloration layer, which is an oxidation discoloration layer, including an adhesion enhancer, the antioxidant, the leveling agent, and the solvent. Alternatively, the first discoloration material composition may be a composition that forms a first discoloration layer, which is an oxidation discoloration layer, including the nickel oxide, the dispersant, the adhesion enhancer, the antioxidant, the leveling agent, and the solvent. The second color change material composition may be a composition that includes a reductive color change material and forms a second color change layer, which is a reduction color change layer.

Meanwhile, according to one embodiment, each coating of the first color change material composition and the second color change material composition may be performed by wet coating, but the coating is not limited thereto. Specifically, the first discoloring material composition is wet-coated on the first electrode layer and dried to form a first discoloring layer, and the second discoloring material composition is wet-coated on the second electrode layer and then dried to form a second discoloring layer. can do. By wet coating each color change material composition, a first color change layer and/or a second color change layer having a uniform and various thickness range can be easily formed. In addition, since coating of each color change material composition is performed at relatively low temperature and normal pressure compared to vacuum deposition coating performed at high temperature, the flexibility of the electrochromic device can be secured by freely using polymer film substrates that are vulnerable to high temperature and low pressure.

Step (6) is a step of forming an electrolyte layer between the first discoloring layer and the second discoloring layer using the gel electrolyte prepared in step (2). For example, it can be formed by wet coating a gel-type electrolyte on one surface of either the first discoloration layer or the second discoloration layer, followed by drying and curing. By wet coating the gel-type electrolyte to form an electrolyte layer, an electrolyte layer having various thickness ranges can be easily formed, and thus ionic conductivity and discoloration rate can be flexibly adjusted.

The step (7) is to manufacture a light transmission variable structure by combining the lower plate and the upper plate so that the first electrode layer, the first discoloration layer, the electrolyte layer, the second discoloration layer, and the second electrode layer are stacked in that order. It's a step. For example, a variable light transmission structure can be manufactured by laminating the lower plate and the upper plate and maturing them at 100 to 150° C. for 20 minutes to 1 hour.

The present invention will be described in more detail through examples below. However, the scope of the present invention is not limited to these examples.

Example 1. Manufacturing of electrochromic device

(1) Nickel oxide production

A mixture was prepared by mixing 2 g of Nickel Acetate tetrahydrate and 100 g of ethanol, and then placed in an autoclave and reacted at 200° C. for 24 hours under 500 psi to prepare a reactant. Next, the reaction was washed with ethanol and centrifuged for 3 hours. Afterwards, 2 g of the product obtained by centrifugation was placed in a sintering furnace and sintered at 300° C. for 4 hours to produce nickel oxide.

(2) Electrolyte preparation

A reaction tank equipped with a four-necked round glass flask, a steel stirring rod, a Teflon stirring seal, a tube cooler, a heating mantle, a temperature sensor, and a joint stopper was installed, and a nitrogen (N ₂ ) atmosphere was maintained. Next, 5 g of lithium bis(oxalato)borate, 50 g of acetone, and 1 g of (C ₆ F ₅ ) ₃ B were added to the reaction tank, and stirred at 500 rpm for 10 minutes at room temperature to obtain a clear solution. Afterwards, 1000 g of acrylic resin and 60 g of 2,2'-dimethoxy-2-phenylacetophenone were added to a light-blocked reaction tank and stirred at 50 rpm for 24 hours at 25°C to prepare a transparent gel electrolyte. .

(3) Manufacturing of upper and lower plates

ITO electrode layers (first electrode layer/second electrode layer) were formed on a PET substrate (thickness: 23 ㎛) through vacuum sputtering to manufacture the upper and lower plates, respectively.

(4) Formation of the first discoloration layer

A tungsten oxide paste (first discoloration material composition) was wet coated on the ITO electrode layer (first electrode layer) of the lower plate and dried at 140° C. for 5 minutes to form a reduced discoloration layer (first discoloration layer) with a thickness of 700 nm. .

(5) Formation of second discoloration layer

A nickel oxide composition (second discoloration material composition) was wet-coated on the ITO electrode layer (second electrode layer) of the upper plate and dried at 140 ° C. for 5 minutes to form an oxidation discoloration layer (second discoloration layer) with a thickness of 700 nm. . At this time, the nickel oxide composition is prepared by mixing the nickel oxide, adhesion enhancer (phosphoric acid-based copolymer), and dispersant (BASF, EFKA PU 4010) prepared in step (1) at 25°C through a ball mill (ball diameter: 20 to 50 nm). After dispersing at 100 rpm for 24 hours to prepare a dispersion (average particle size of nickel oxide in the dispersion 30 nm), it was mixed with an organic solvent (ethanol) along with an antioxidant (MERCK, tert-Butylhydroquinone) and a leveling agent (BASF, EFKA 3030). The product obtained through the dilution process was used. In addition, the composition of the nickel oxide composition was 20% by weight of nickel oxide, 2% by weight of adhesion enhancer, 1% by weight of dispersant, 1% by weight of antioxidant, 1% by weight of leveling agent, and 75% by weight of organic solvent.

(6) Electrolyte layer formation

Place the electrolyte prepared in step (2) on the reduced discoloration layer of the lower plate, dry at 80°C for 30 seconds, and irradiate UV light of 365 nm for 60 seconds with a UV lamp to form an electrolyte layer with a thickness of 100 ㎛. did.

(7) Manufacturing of variable light transmission structure

After laminating the lower plate and the upper plate so that the oxidation discoloration layer of the upper plate is on the electrolyte layer of the lower plate, placing it in an oven and maturing at 120 ° C. for 30 minutes, PET substrate / ITO electrode layer / reduction discoloration layer / electrolyte layer A light transmission variable structure having a layered structure in the order of /oxidation discoloration layer/ITO electrode layer/PET substrate was manufactured. Afterwards, an electrochromic device was manufactured by providing an electrode layer capable of connecting to a power source on the side of each ITO electrode layer of the upper and lower plates.

Test example 1

The composition of the nickel oxide prepared in step (1) of Example 1 was analyzed by XPS (X-ray Photoelectron Spectroscopy), and the results are shown in Table 1 below.

No. Furtherance Proportion (% by weight) One NiO 0.01 2 _NiO2 0.40 3 Ni ₂ O ₃ 0.01 4 Ni ₂ O 0.01 5 Ni ₃ O 0.01 6 _Ni4O 0.01 7 Ni ₃ O ₄ 99.55

Referring to Table 1, it was confirmed that the nickel oxide used as the discoloring material of the oxidation discoloring layer in Example 1 was a nickel oxide containing 95% by weight or more of nickel oxide represented by Ni ₃ O ₄ .

Examples 2 to 4 and Comparative Example 1

An electrochromic device was manufactured through the same process as Example 1, except that nickel oxide whose content represented by Ni ₃ O ₄ was controlled as shown in Table 2 below was applied.

Test example 2

The physical properties of the electrochromic devices manufactured in Examples 1 to 4 and Comparative Example 1 were evaluated in the following manner, and the results are shown in Table 2 below.

1. Tinted color

A voltage of 2.0V was applied to the electrochromic device in the maximum discoloration state at room temperature to change it to the maximum coloration state, and then the displayed color was confirmed based on RGB color coordinates.

2. Ion conductivity

The ionic conductivity of the electrochromic device was measured using the Nyquist method using an electrochemical impedance spectrometer at room temperature.

3. Discoloration section

DC voltage was applied to the electrochromic device (switching from -2.0V to +2.0V applied repeatedly more than 10 times) to induce coloring and decolorization reactions, and the electrochromic properties at that time were measured. The electrochromism was determined by using a transmittance measuring device (Avantes, Netherlands) to determine the degree to which light in the wavelength range of 300 to 800 nm is transmitted through the electrochromic device (transmittance). 550 nm is known to be the most sensitive to the human eye among the visible light ranges. The transmittance was measured.

Among the above transmittance measurement results, the initial transmittance (%) measured in the maximum discoloration state is applied as the lower limit of the discoloration section, and the initial transmittance (%) measured in the maximum discoloration state is applied as the upper limit of the discoloration section to calculate the discoloration section range. did.

division Ni ₃ O ₄ content tinted color Ion conductivity
(mS/cm) Discoloration section Example 1 99.55% by weight full black 1×10 ^-3 mS/cm 27.9 to 69.2% Example 2 85% to less than 95% by weight full black 1×10 ^-3 mS/cm 32.6 to 68.3% Example 3 75% to less than 85% by weight full black 1×10 ^-3 mS/cm 35.1 to 58.7% Example 4 65% to less than 75% by weight Some area black + some area gray 1×10 ^-3 mS/cm 36.2 to 65.5% Comparative Example 1 Less than 50% by weight Color cannot be confirmed due to poor operation Measurement not possible due to poor drive Measurement not possible due to poor drive

Referring to Table 2 above, it was confirmed that by using nickel oxide with a Ni ₃ O ₄ content of 65% by weight or more as a color change material, the electrochromic device was operated well, had high ion conductivity, and realized black color. In particular, it was confirmed that when the content of Ni ₃ O ₄ was 95% by weight or more (Example 1), an electrochromic device with the widest discoloration zone and uniform black color was obtained.

On the other hand, as in Comparative Example 1, it was confirmed that the operation of the electrochromic device itself was impossible as nickel oxide with a Ni ₃ O ₄ content of less than 65% by weight was used.

Examples 5 to 7

An electrochromic device was manufactured through the same process as Example 1, except that the average particle size of the nickel oxide contained in the nickel oxide composition (second discoloration material composition) for forming the oxidation discoloration layer was adjusted as shown in Table 3 below. did.

Test example 3

The coloring color and color change interval of the electrochromic devices manufactured in Examples 1 and 5 to 7 were evaluated in the same manner as Test Example 2, and the results are shown in Table 3 below.

division Nickel oxide average particle size (D ₅₀ ) tinted color Discoloration section Example 1 30 nm full black 27.9 to 69.2% Example 5 20 nm Some area black + some area gray 30.0 to 68.7% Example 6 8nm Color cannot be confirmed due to poor operation - Example 7 230nm Color cannot be confirmed due to poor operation -

Referring to Table 3 above, it was confirmed that the average particle size of nickel oxide used as a color change material affects the driving characteristics of the electrochromic device. Specifically, it was confirmed that the driving characteristics of the electrochromic device were excellent when the average particle size of nickel oxide was 25 to 35 nm.

On the other hand, if the average particle size of nickel oxide is less than 10 nm, damage to the electrochromic device occurred during repeated driving, and if the average particle size of nickel oxide was more than 200 nm, precipitation of nickel oxide occurred when manufacturing the nickel oxide composition to form the oxidation color change layer. As this occurred, the oxidized color change layer was not formed stably, making it difficult to implement an electrochromic device that could be driven.

100: Electrochromic device
110: Light transmission variable structure
111: first electrode layer
112: first discoloration layer
113: electrolyte layer
114: second discoloration layer
115: second electrode layer
120: first substrate layer
130: second substrate layer
140: barrier layer
150: Primer layer
160: Hard coating layer
170: Adhesive layer
180: Release film layer

Claims (10)

It includes a variable light transmission structure including a first electrode layer, a first discoloration layer, an electrolyte layer, a second discoloration layer, and a second electrode layer,
The first discoloring layer or the second discoloring layer includes a discoloring material containing nickel oxide,
An electrochromic device wherein the content of nickel oxide expressed as Ni ₃ O ₄ contained in the nickel oxide is 65% by weight or more based on the total weight of the nickel oxide.
According to claim 1,
An electrochromic device wherein the average particle diameter (D ₅₀ ) of the nickel oxide is 20 to 80 nm.
According to claim 1,
An electrochromic device wherein the content of nickel oxide expressed as Ni ₃ O ₄ contained in the nickel oxide is 75 to 99.9% by weight based on the total weight of the nickel oxide.
According to claim 1,
The nickel oxide may be nickel oxide represented by NiO, nickel oxide represented by NiO ₂ , nickel oxide represented by Ni ₂ O ₃ , nickel oxide represented by Ni ₂ O, nickel oxide represented by Ni ₃ O, and Ni ₄ O. An electrochromic device further comprising two or more types of nickel oxide selected from the group consisting of nickel oxide represented by .
According to claim 1,
An electrochromic device wherein the content of nickel oxide in the first color-changing layer or the second color-changing layer is 15 to 95% by weight based on the total weight of each color-changing layer.
According to claim 1,
An electrochromic device that, when changed to the maximum coloring state, exhibits a color in the range where the R coordinate value is 0 to 0.125, the G coordinate value is 0 to 0.156, and the B coordinate value is 0 to 0.188 in the RGB color coordinates.
(1) producing nickel oxide;
(2) preparing a gel type electrolyte;
(3) manufacturing a lower plate including a first electrode layer and an upper plate including a second electrode layer by coating electrode materials on the first and second substrates, respectively;
(4) forming a first discoloration layer by coating a first discoloration material composition on the first electrode layer;
(5) forming a second discoloration layer by coating a second discoloration material composition on the second electrode layer;
(6) forming an electrolyte layer between the first discoloring layer and the second discoloring layer; and
(7) It includes the step of manufacturing a light transmission variable structure by combining the lower plate and the upper plate so that the first electrode layer, the first discoloration layer, the electrolyte layer, the second discoloration layer, and the second electrode layer are stacked in that order. do,
The first discoloring material composition or the second discoloring material composition includes a discoloring material containing nickel oxide prepared in step (1),
A method of manufacturing an electrochromic device, wherein the content of nickel oxide expressed as Ni ₃ O ₄ contained in the nickel oxide is 65% by weight or more based on the total weight of the nickel oxide.
According to claim 7,
The step (1) is,
(1-1) preparing a reactant by adding a mixture of a nickel oxide precursor and a solvent into a high pressure reactor and reacting at 150 to 250° C. under 400 to 600 psi; and
(1-2) A method of manufacturing an electrochromic device, comprising the step of putting the reactant into a sintering furnace and sintering it at 250 to 350° C.
According to claim 7,
A method of manufacturing an electrochromic device, wherein the first color change material composition or the second color change material composition contains 5 to 30% by weight of nickel oxide prepared in step (1), based on the total weight of each color change material composition. .
According to claim 7,
A method of manufacturing an electrochromic device, wherein the coating in step (4) and step (5) is wet coating, respectively.