阅读说明：本技术 电致变色器件 (Electrochromic device ) 是由 吴云秀 孙妏暎 李仁会 柳志昌 朴镇庆 李东建 于 2018-04-13 设计创作，主要内容包括：本发明的一实施例涉及的电致变色器件包括：第一基板；第一电极,配置在所述第一基板的上侧；第一变色物质层,配置在所述第一电极的上侧并包含第一变色物质；电解质层,配置在所述第一变色物质层的上侧；第二变色物质层,配置在所述电解质层的上侧并包含第二变色物质；第二电极,配置在所述第二变色物质层的上侧,以及第二基板,配置在所述第二电极的上侧,其中,所述第一基板以及所述第二基板中的至少一个为透明基板,所述第一电极以及所述第二电极中的至少一个为透明电极,所述电解质层包括可聚合单体、可聚合低聚物及聚合物中的至少一种、第一离子性液体以及不同于所述第一离子性液体的第二离子性液体。(An embodiment of the present invention relates to an electrochromic device including: a first substrate; a first electrode disposed on an upper side of the first substrate; a first color-changing material layer which is disposed on the upper side of the first electrode and contains a first color-changing material; an electrolyte layer disposed on the first color-changing material layer; a second color-changing material layer which is disposed on the upper side of the electrolyte layer and contains a second color-changing material; a second electrode disposed on an upper side of the second color changing material layer, and a second substrate disposed on an upper side of the second electrode, wherein at least one of the first substrate and the second substrate is a transparent substrate, at least one of the first electrode and the second electrode is a transparent electrode, and the electrolyte layer includes at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, a first ionic liquid, and a second ionic liquid different from the first ionic liquid.)

1. An electrochromic device, comprising:

a first substrate;

a first electrode disposed on an upper side of the first substrate;

a first color-changing material layer which is disposed on the upper side of the first electrode and contains a first color-changing material;

an electrolyte layer disposed on the first color-changing material layer;

a second color-changing material layer which is disposed on the upper side of the electrolyte layer and contains a second color-changing material;

a second electrode disposed on the second color-changing material layer; and

a second substrate disposed above the second electrode,

wherein at least one of the first substrate and the second substrate is a transparent substrate, at least one of the first electrode and the second electrode is a transparent electrode,

the electrolyte layer includes at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, a first ionic liquid, and a second ionic liquid different from the first ionic liquid,

the first ionic liquid is an ionic liquid that is unreactive with at least one of the polymerizable monomer, polymerizable oligomer, and polymer,

the second ionic liquid is an ionic liquid capable of reacting with at least one of the polymerizable monomer, polymerizable oligomer, and polymer.

2. The electrochromic device according to claim 1,

the second ionic liquid is an ionic liquid in which the positive ion comprises a carbon-carbon double bond or a carbon-carbon triple bond.

3. The electrochromic device according to claim 2,

the second ionic liquid is an ionic liquid in which the positive ion contains a vinyl group or an acrylate group.

4. The electrochromic device according to claim 3,

the second ionic liquid is an ionic liquid in which the positive ion further contains at least one of imidazolium or ammonium.

5. The electrochromic device according to claim 4,

the positive ion of the second ionic liquid comprises 1-methyl-3-vinylimidazolium (1-methyl-3-vinylimidazolium) or [ (3-methacrylamido) propyl ] trimethylammonium ([ (3-methacryloylamido) propyl ] trimethylammonium).

6. The electrochromic device according to claim 2,

the positive ion of the first ionic liquid includes at least one of ammonium (ammonium), imidazolium (imidazolium), oxazolium (oxazolium), piperidinium (piperidinium), pyrazinium (pyrazinium), pyrazolium (pyrazolium), pyridazinium (pyridazinium), pyridinium (pyridinium), pyrimidinium (pyrimidinium), pyrrolidinium (pyrrolidinium), pyrrolinium (pyrrolinium), pyrronium (pyrrolium), thiazolium (thiazolium), and triazolium (triazolium).

7. The electrochromic device according to claim 6,

the second ionic liquid is contained in an amount of 5 to 15 parts by weight relative to 10 parts by weight of the first ionic liquid.

8. The electrochromic device according to claim 2,

the electrolyte layer further includes a lithium salt.

9. The electrochromic device according to claim 2,

the electrolyte layer further includes a photoinitiator.

10. An electrochromic device, comprising:

an electrochromic device;

a first terminal portion connected to the first electrode and having a first polarity; and

a second terminal portion connected to the second electrode and having a second polarity,

the electrochromic device includes:

a first substrate;

a first electrode disposed on an upper side of the first substrate;

a first color-changing material layer which is disposed on the upper side of the first electrode and contains a first color-changing material;

an electrolyte layer disposed on the first color-changing material layer;

a second color-changing material layer which is disposed on the upper side of the electrolyte layer and contains a second color-changing material;

a second electrode disposed on the second color-changing material layer; and

a second substrate disposed above the second electrode,

wherein at least one of the first substrate and the second substrate is a transparent substrate, at least one of the first electrode and the second electrode is a transparent electrode,

the electrolyte layer includes at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, a first ionic liquid, and a second ionic liquid different from the first ionic liquid,

the first ionic liquid is an ionic liquid that is unreactive with at least one of the polymerizable monomer, polymerizable oligomer, and polymer,

the second ionic liquid is an ionic liquid capable of reacting with at least one of the polymerizable monomer, polymerizable oligomer, and polymer.

Technical Field

The present invention relates to an electrochromic device. And more particularly to electrolyte layers included in electrochromic devices.

Background

Electrochromism (Electrochromism) refers to a phenomenon in which a color is reversibly changed due to the direction of an electric field when a voltage is applied, and a substance having such a property, in which the optical property of a material is reversibly changed due to an electrochemical redox reaction, is referred to as an electrochromic substance. This electrochromic substance has the following characteristics: when no electric signal is applied from the outside, no color is displayed and when an electric signal is applied, a color is displayed, or conversely, when no electric signal is applied from the outside, a color is displayed and when an electric signal is applied, a color disappears.

An electrochromic device is a device utilizing a phenomenon that the light transmittance of an electrochromic substance changes due to an electrochemical redox reaction, and is used for adjusting the light transmittance or reflectance of displays such as Electronic Shelf Labels (ESL) that require a specific portion to change color, public devices such as large posters and information boards, smart windows, architectural window glass, automobile mirrors, flexible displays, automobile skylights, and sports glasses, and recently, has an infrared shielding effect in addition to color change in a visible light region, and is attracting attention as an application prospect of energy saving products.

The performance of such electrochromic devices varies with the rate of color change, which can be affected by the electrolyte. Therefore, in order to improve the discoloration rate, an attempt has been made to form an electrolyte with an ionic liquid. An ionic liquid refers to a salt in a liquid state, and positive ions and negative ions exhibit electrical neutrality by making the charges of each other zero. Ionic liquids have low vapor pressure, non-flammability, electrochemical stability, and high ionic conductivity at normal temperature, and thus are drawing attention as electrolyte materials.

When an ionic liquid is used alone as a material of an electrolyte, there is a limitation in processing of a film form and thinning of a color changing device due to leakage of the electrolyte. In order to solve these problems, an ionic liquid and a polymer may be mixed and then cured by UV or heat, but even in this case, there is a problem that the electrolyte layer is transferred to the transparent electrode after repeated driving.

Disclosure of Invention

Technical problem

The technical problem to be solved by the invention is to provide an electrolyte layer of an electrochromic device.

Technical scheme

An electrochromic device of an embodiment of the present invention includes: a first substrate; a first electrode disposed on an upper side of the first substrate; a first color-changing material layer which is disposed on the upper side of the first electrode and contains a first color-changing material; an electrolyte layer disposed on the first color-changing material layer; a second color-changing material layer which is disposed on the upper side of the electrolyte layer and contains a second color-changing material; a second electrode disposed on the second color-changing material layer; and a second substrate disposed on an upper side of the second electrode, at least one of the first substrate and the second substrate being a transparent substrate, at least one of the first electrode and the second electrode being a transparent electrode, the electrolyte layer including at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, a first ionic liquid, and a second ionic liquid different from the first ionic liquid, the first ionic liquid being an ionic liquid unreactive with the at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer, the second ionic liquid being an ionic liquid reactable with the at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer.

The second ionic liquid is an ionic liquid in which the positive ion comprises a carbon-carbon double bond or a carbon-carbon triple bond.

The second ionic liquid is an ionic liquid in which the positive ion contains a vinyl group or an acrylate group.

The second ionic liquid is an ionic liquid in which the positive ion further contains at least one of imidazolium or ammonium.

The positive ion of the second ionic liquid comprises 1-methyl-3-vinylimidazolium (1-methyl-3-vinylimidazolium) or [ (3-methacrylamido) propyl ] trimethylammonium ([ (3-methacryloylamido) propyl ] trimethylammonium).

The positive ion of the first ionic liquid includes at least one of ammonium (ammonium), imidazolium (imidazolium), oxazolium (oxazolium), piperidinium (piperidinium), pyrazinium (pyrazinium), pyrazolium (pyrazolium), pyridazinium (pyridazinium), pyridinium (pyridinium), pyrimidinium (pyrimidinium), pyrrolidinium (pyrrolidinium), pyrrolinium (pyrrolinium), pyrronium (pyrrolium), thiazolium (thiazolium), and triazolium (triazolium).

The second ionic liquid is contained in an amount of 5 to 15 parts by weight relative to 10 parts by weight of the first ionic liquid.

The electrolyte layer further includes a lithium salt.

The electrolyte layer further includes a photoinitiator.

An electrochromic device of an embodiment of the present invention includes: an electrochromic device; a first terminal portion connected to the first electrode and having a first polarity; and a second terminal portion connected to the second electrode and having a second polarity, the electrochromic device including: a first substrate; a first electrode disposed on an upper side of the first substrate; a first color-changing material layer which is disposed on the upper side of the first electrode and contains a first color-changing material; an electrolyte layer disposed on the first color-changing material layer; a second color-changing material layer which is disposed on the upper side of the electrolyte layer and contains a second color-changing material; a second electrode disposed on the second color-changing material layer; and a second substrate disposed on an upper side of the second electrode, at least one of the first substrate and the second substrate being a transparent substrate, at least one of the first electrode and the second electrode being a transparent electrode, the electrolyte layer including at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, a first ionic liquid, and a second ionic liquid different from the first ionic liquid, the first ionic liquid being an ionic liquid unreactive with the at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer, the second ionic liquid being an ionic liquid reactable with the at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer.

Effects of the invention

According to the embodiment of the invention, the electrochromic device with high color change speed can be obtained.

In particular, according to the embodiments of the present invention, an electrolyte layer can be obtained which has a high discoloration rate, is free from a risk of leakage, can be processed in a film form or a thin film form, and does not migrate or diffuse to a transparent electrode.

In addition, according to the embodiments of the present invention, it is possible to improve the bonding force between the transparent electrode and the color-changing substance layer or between the electrochromic substance layer and the electrolyte layer, and thus to improve the ionic conductivity and the color-changing speed.

In addition, according to the embodiments of the present invention, it is possible to increase the ionic conductivity in the color-changing substance layer, and thus to increase the color-changing speed.

Drawings

Fig. 1 is a cross-sectional view of an electrochromic device according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view of an electrochromic device according to another embodiment of the invention.

Fig. 3 is a cross-sectional view of an electrochromic device according to a further embodiment of the invention.

Fig. 4 is a photograph of the electrolyte layer of example 3 after repeated driving.

Fig. 5 is a photograph of the electrolyte layer of comparative example 1 after repeated driving.

Fig. 6 to 10 are cross-sectional views of a part of an electrochromic device according to an embodiment of the present invention.

Fig. 11 is a layer of color-changing substance showing an embodiment of the present invention.

Fig. 12 is a graph comparing the performance of the electrochromic devices of comparative example 11 and example 11.

Fig. 13 is a plan view for explaining an example in which an electrochromic device according to an embodiment of the present invention is applied to an ESL, and fig. 14 is a sectional view of a part of fig. 13.

Fig. 15 is an electrochromic apparatus including an electrochromic device illustrating an embodiment of the present invention.

Fig. 16 is a diagram showing an electronic shelf label system to which an electrochromic device according to an embodiment of the present invention is applied.

Detailed Description

While the invention is susceptible to various modifications and alternative embodiments, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. However, the present invention is not limited to the specific embodiments, and all modifications, equivalents, and alternatives included in the spirit and technical scope of the present invention are encompassed.

Terms including such terms as second, first, etc. may be used to describe various elements, but the elements are not limited to the terms. The terms are only used to distinguish one constituent element from another constituent element. The second component may be named the first component, and similarly, the first component may also be named the second component without departing from the scope of the present invention. The term "and/or" includes a combination of a plurality of related items or one of a plurality of related items.

When a certain component is referred to as being "connected" or "in contact with" another component, this includes not only a case where the component is directly connected or in contact with the other component but also a case where the other component is present in the middle thereof. Conversely, when a component is referred to as being "directly connected" or "directly contacting" another component, it is to be understood that no other component is present therebetween.

In the description of the embodiments, the description that each layer (film), region, pattern, or structure is formed on "or" under "of the substrate, each layer (film), region, pad, or pattern includes all the cases where the layer is formed directly (directly) or via another layer. References to up/over or down/under of the respective layers will be described with reference to the drawings. In addition, the thickness or size of each layer (film), region, pattern, or structure in the drawings may be changed for clarity and convenience of description, and thus does not completely reflect the actual size.

The terminology used in the description presented herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Unless the context clearly dictates otherwise, expressions in the singular include expressions in the plural. In the present application, the terms "including" or "having" and the like are intended to specify the presence of the features, numerals, steps, operations, constituent elements, components, or combinations thereof described in the specification, and do not preclude the presence or addition of one or more other features, numerals, steps, operations, constituent elements, components, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their contextual meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings, and the same or corresponding constituent elements are given the same reference numerals regardless of the reference numerals, and overlapping descriptions thereof will be omitted.

Fig. 1 is a cross-sectional view of an electrochromic device according to an embodiment of the present invention.

Referring to fig. 1, an electrochromic device 100 includes: a first electrode portion 110; a first color-changing material layer 120 which is disposed above the first electrode portion 110 and contains a first color-changing material; an electrolyte layer 130 disposed on the first color-changing material layer 120; a second color-changing material layer 140 which is disposed on the upper side of the electrolyte layer 130 and contains a second color-changing material; and a second electrode portion 150 disposed on the second color-changing material layer 140. The first electrode portion 110 and the second electrode portion 150 are connected to the first terminal portion 160 and the second terminal portion 170, respectively, which have different polarities, and receive power supply from the first terminal portion 160 and the second terminal portion 170. Sealing part 180 may be further provided on the side surfaces of first color-changing material layer 120, second color-changing material layer 140, and electrolyte layer 130.

At this time, the first electrode part 110 may include the first transparent substrate 112 and the first transparent electrode 114, and the second electrode part 150 may include the second transparent substrate 152 and the second transparent electrode 154.

The first transparent substrate 112 and the second transparent substrate 152 are transparent substrates having a light transmittance T (%) of 98% or more, and may be glass, plastic, or a flexible polymer film. For example, the flexible polymer film may be formed of any one of Polyethylene Terephthalate (PET), Polycarbonate (PC), acrylonitrile-butadiene-styrene Copolymer (ABS), Polymethyl Methacrylate (PMMA), Polyethylene Naphthalate (PEN), Polyethersulfone (PES), Cyclic Olefin Copolymer (COC), triacetyl cellulose (TAC), Polyvinyl alcohol (PVA), Polyimide (PI), Polystyrene (PS), which is just one example and not limited thereto.

The first color-changing material layer 120, the electrolyte layer 130, and the second color-changing material layer 140 include a device that reversibly changes color or light transmittance by voltage applied from the outside using an electrochromic principle in which color changes when voltage is applied. The total thickness of the first color-changing material layer 120, the electrolyte layer 130 and the second color-changing material layer 140 may be 10 to 500 μm, preferably 20 to 300 μm, and more preferably 50 to 200 μm. When the total thickness of the first color-changing material layer 120, the electrolyte layer 130, and the second color-changing material layer 140 is less than 10 μm, short circuits may be caused by contact between the first transparent electrode 114 and the second transparent electrode 154, and when the total thickness of the first color-changing material layer 120, the electrolyte layer 130, and the second color-changing material layer 140 is more than 500 μm, the conductivity is reduced, and the reaction rate may be reduced.

The first color-changing material layer 120 and the second color-changing material layer 140 may include a material that is excellent in color-changing or decoloring property, is excellent in reaction speed, can maintain durability, and has a memory effect. For example, the first color-changing material layer 120 may be an oxidation color-changing layer that performs an oxidation reaction, and the second color-changing material layer 140 may be a reduction color-changing layer that performs a reduction reaction. Alternatively, the first color-changing material layer 120 may be a reduction color-changing layer that performs a reduction reaction, and the second color-changing material layer 140 may be an oxidation color-changing layer that performs an oxidation reaction.

The first color-changing material layer 120 and the second color-changing material layer 140 may include at least one of an organic color-changing material and an inorganic color-changing material. In the present specification, the color-changing substance is a substance havingA substance that changes the electrochromic characteristics of light absorption rate by electrochemical oxidation and reduction reaction reversibly generates electrochemical oxidation and reduction phenomena of the electrochromic substance depending on whether or not a voltage is applied and the intensity of the voltage, and thus can reversibly change the transparency and light absorption rate of the electrochromic substance. The organic type color-changing substances may be selected from, for example, viologens, anthraquinones, polypyrroles and polythiophenes, polyanthrylenes, polyfluorenes, polycarbazoles, polyphenylvinylenes and derivatives thereof, and the inorganic type color-changing substances may be selected from, for example, oxides of tungsten, iridium, nickel, vanadium, molybdenum, manganese, titanium, cerium and niobium. Also, the color-changing substance may be Prussian Blue (PB), Prussian Blue Analog (PBA). WO₃May be a color-changing substance contained in the reduction-discoloring layer, and PB may be a color-changing substance contained in the oxidation-discoloring layer.

The first transparent electrode 114 and the second transparent electrode 154 may each include a transparent conductive material that allows a current to flow therethrough without obstructing light transmission. For example, the transparent conductive material may include metal oxides such as ITO (Indium Tin Oxide), FTO (Fluorine Tin Oxide), IZO (Indium Zinc Oxide), copper Oxide (Tin Oxide), Zinc Oxide (Zinc Oxide), and titanium Oxide (titanium Oxide). Also, the transparent conductive material may further include a Nano powder composite material such as a Nano wire, a photosensitive Nano wire film, a CNT (Carbon nanotube), graphene (graphene), or a mixture thereof. Wherein the content of the nano powder is controlled to ensure conductivity and control color and reflectivity. Alternatively, the transparent conductive material may further include at least one of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo), gold (Au), titanium (Ti), and an alloy thereof. The first transparent electrode 114 and the second transparent electrode 154 may be respectively in a film shape, and the light transmittance may be 80% or more.

Fig. 2 is a cross-sectional view of an electrochromic device according to another embodiment of the invention. For the same thing as fig. 1, the duplicate explanation will be omitted.

Referring to fig. 2, the electrochromic device 100 includes: a first electrode portion 110; a first color-changing material layer 120 which is disposed above the first electrode portion 110 and contains a first color-changing material; an electrolyte layer 130 disposed on the first color-changing material layer 120; a second color-changing material layer 140 which is disposed on the upper side of the electrolyte layer 130 and contains a second color-changing material; and a second electrode portion 150 disposed on the second color-changing material layer 140. The first electrode portion 110 and the second electrode portion 150 are connected to the first terminal portion 160 and the second terminal portion 170, respectively, which have different polarities, and receive power supply from the first terminal portion 160 and the second terminal portion 170. Sealing part 180 may be further disposed on the side surfaces of first color-changing material layer 120, second color-changing material layer 140, and electrolyte layer 130.

At this time, the first electrode part 110 may include the first transparent substrate 112 and the first transparent electrode 114, and the second electrode part 150 may include the second transparent substrate 152 and the second transparent electrode 154.

According to an embodiment of the present invention, the lower portion of the first electrode layer 110 may be further provided with a substrate 200 having a predetermined color. The predetermined color may be white, so that the color-changed characters, numbers, pictures, etc. may be more clear. The predetermined color may be a color other than white. The color of the discolored characters, numerals, pictures, etc. may be finely adjusted according to the color of the substrate 200. According to the embodiment of the present invention, when the electrochromic device is applied to an ESL (electronic shelf label) display, a digital signage (digital signage), an E-paper (electronic paper), or the like, the color of characters, numbers, pictures, or the like to be displayed can be clearly realized.

Fig. 3 is a cross-sectional view of an electrochromic device according to still another embodiment of the present invention, and the same contents as those of fig. 1 to 2 will be omitted from repeated description.

Referring to fig. 3, the electrochromic device 100 includes: a first electrode portion 110; a first color-changing material layer 120 which is disposed above the first electrode portion 110 and contains a first color-changing material; an electrolyte layer 130 disposed on the first color-changing material layer 120; a second color-changing material layer 140 which is disposed on the upper side of the electrolyte layer 130 and contains a second color-changing material; a second electrode portion 150 disposed on the second color-changing material layer 140; a first terminal portion 160 connected to the first electrode portion 110 and having a first polarity; and a second terminal portion 170 connected to the second electrode portion 150 and having a second polarity.

According to an embodiment of the present invention, one of the first electrode portion 110 and the second electrode portion 150, for example, the second electrode portion 150, may include a transparent substrate 152 and a transparent electrode 154. Among them, the transparent electrode 154 may be disposed on a surface facing the electrolyte layer among both surfaces of the transparent substrate 152 and include a transparent conductive material.

The other of the first electrode portion 110 and the second electrode portion 150, for example, the first electrode portion 110 includes a conductive substrate of a predetermined color. The predetermined color may be white, but is not limited thereto, and may have various colors other than transparent. The conductive substrate of a predetermined color may be formed by a method of plating or depositing at least one of Sn, Ag, Al, Cu, Al, and Mo. The conductive substrate of a predetermined color can have a single-layer or multi-layer structure. The predetermined color may be different according to the kind of metal plated or deposited, the particle size, and the like.

In this manner, when the first electrode portion 110 includes a conductive substrate having a predetermined color other than transparency, not only can the color of the discolored region such as characters, numerals, and pictures be displayed more clearly, but also 10 is used^-2To 10^-3Low surface resistance of omega/sq, and high-speed color change.

On the other hand, according to an embodiment of the present invention, the electrolyte layer 130 includes one of a polymerizable monomer, a polymerizable oligomer, and a polymer, a first ionic liquid, and a second ionic liquid different from the first ionic liquid. At this time, the polymerizable monomer, polymerizable oligomer, and polymer may be contained in an amount of 10 to 30% by weight, preferably 10 to 20% by weight, and the first ionic liquid and the second ionic liquid different from the first ionic liquid may be contained in an amount of 70 to 90% by weight, preferably 80 to 90% by weight, relative to 100% by weight of one of the polymerizable monomer, polymerizable oligomer, and polymer, the first ionic liquid, and the second ionic liquid different from the first ionic liquid. When the first ionic liquid and the second ionic liquid are contained in a range smaller than the above numerical value, the discoloration speed may be lowered. When the first ionic liquid and the second ionic liquid are contained in a range larger than the above range, the electrolyte layer and the electrode layer may be separated from each other, and the electrolyte layer may be aggregated.

The polymerizable monomer, polymerizable oligomer, and polymer may function as a matrix (matrix) in the electrolyte layer 130, and may be selected from an acrylic monomer, an acrylic oligomer, an acrylic polymer, an acrylate monomer, an acrylate oligomer, an acrylate polymer, a carbonate monomer, a carbonate oligomer, and a carbonate polymer. Examples of the polymerizable monomer, polymerizable oligomer, and polymer include urethane acrylate, acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, methylstyrene, vinyl ester compounds, vinyl chloride, vinylidene chloride, acrylamide, tetrafluoroethylene, vinyl acetate, methyl vinyl ketone, ethylene, styrene, p-methoxystyrene, p-cyanostyrene, and polyethylene glycol acrylate, and these may be used alone or in combination of two or more. The polymerizable monomers, polymerizable oligomers, and polymers may be monomers, oligomers, and polymers exemplified in the following chemical formulas 1 to 3.

Chemical formula 1:

chemical formula 2:

chemical formula 3:

polymerizable monomers, polymerizable oligomers, and polymers can be polymerized by UV or heat. For this purpose, the electrolyte layer 130 may further include an azo compound such as AIBN (Azobisisobutyronitrile) as a thermal initiator or Irgacure-184, Darocure, or the like as a photoinitiator. The content of the thermal initiator or the photoinitiator in the electrolyte layer may be 0.5 to 1.5% by weight, as an example of the photoinitiator, as shown in chemical formula 4.

Chemical formula 4:

the ionic liquid is a salt in a liquid state and is composed of ions, but positive ions and negative ions are electrically neutral by making the charges of the positive ions and the negative ions zero. According to an embodiment of the present invention, the first ionic liquid and the second ionic liquid are different types of ionic liquids, the first ionic liquid is an ionic liquid that is unreactive with at least one of polymerizable monomers, polymerizable oligomers, and polymers, and the second ionic liquid is an ionic liquid that is unreactive with at least one of polymerizable monomers, polymerizable oligomers, and polymers.

For example, the positive ion contained in the first ionic liquid may be ammonium (ammonium), imidazolium (imidazolium), oxazolium (oxazolium), piperidinium (piperidinium), pyrazinium (pyrazinium), pyrazolium (pyrazolium), pyridazinium (pyridazinium), pyridinium (pyridinium), pyrimidinium (pyridinium), pyrrolidinium (pyrrolidium), pyrrolinium (pyrrolinium), pyrrolium (pyrrolium), thiazolium (thiazolium), triazolium (triazolium), and the like, and the negative ion may be halogen, BF, or the like₄ ^-、PF₆ ^-And salts of sulfonic acids [ (SO)₂R)O]^-Imides [ (SO)₂R)₂N]^-And methide [ (SO)₂R)₃C]^-And the like. Wherein R may be halogen, CF₃、C₂F₅And other aryl or alkyl substituents capable of accepting an electron pair. For example, the first ionic liquid may be 1-Decyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide (1-Decyl-3-methylimidazolium b) having the structure of chemical formula 5 belowis (trifluoromethyl and sulfofonyl) imide), but is not limited thereto.

Chemical formula 5:

since the first ionic liquid cannot react with the matrix, i.e., at least one of the polymerizable monomer, polymerizable oligomer, and polymer, it can be uniformly dispersed in the matrix.

In this regard, the second ionic liquid is capable of reacting with the matrix, i.e., at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer. Therefore, the second ionic liquid can be used in combination with the reactive ionic liquid in the present specification. In order to enable the second ionic liquid to react with the substrate, the second ionic liquid may be an ionic liquid in which the positive ion has a carbon-carbon double bond or a carbon-carbon triple bond.

May be a reactive ionic liquid. The reactive ionic liquid may be an ionic liquid in which the positive ion has a carbon-carbon double bond or a carbon-carbon triple bond. When ultraviolet light (UV) is irradiated to an ionic liquid having a carbon-carbon double bond or a carbon-carbon triple bond, radicals are generated, and the generated radicals can react with at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer added as a matrix. In this way, the second ionic liquid is capable of cross-linking polymerization with the matrix and maintaining stable dispersion within the electrolyte layer.

In this case, the positive ion of the second ionic liquid may include a vinyl group or an acrylate group, and the positive ion may further include at least one of imidazolium and ammonium. For example, the positive ion of the second ionic liquid may comprise 1-methyl-3-vinylimidazolium (1-methyl-3-vinylimidazolium) or [ (3-methacryloyl) propyl ] trimethylammonium ([ (3-methacryloylamino) propyl ] trimethylammonium). For example, the positive ion of the second ionic liquid may be one of chemical formula 6, chemical formula 7, or chemical formula 8.

Chemical formula 6:

chemical formula 7:

chemical formula 8:

when the positive ion of the second ionic liquid is the same as that of chemical formula 7, the second ionic liquid may be 3- [ (methacrylamido) propyl ] trimethylammonium bis (trifluoromethanesulfonyl) imide (3- [ (methacrylamido) propyl) trimethylamonium bis (imide) having the structure of chemical formula 9, but is not limited thereto.

Chemical formula 9:

at this time, the second ionic liquid may be contained in an amount of 5 to 15 parts by weight, preferably 5 to 10 parts by weight, more preferably 5 to 8 parts by weight, relative to 10 parts by weight of the first ionic liquid. When the content of the second ionic liquid is more than the numerical range, the reaction with the matrix may be excessive, so that the electrolyte layer as a whole becomes hard, whereby the resistance becomes high, thereby reducing the discoloration rate. When the content of the second ionic liquid is less than the numerical range, the electrolyte layer may be transferred to the electrode portion and diffused.

On the other hand, the electrolyte layer 130 according to an embodiment of the present invention may further include a metal salt, and the metal salt may include lithium ions. For example, lithium ions may be contained in the form of chemical formula 10, and 30 wt% or less, preferably 10 to 30 wt% of lithium ions may be contained with respect to the entire electrolyte layer 130.

Chemical formula 10:

when the electrolyte layer 130 contains lithium ions, a rapid discoloration speed can be obtained due to the low vapor pressure, fire resistance, electrochemical stability of the ionic liquid, and high ionic conductivity at normal temperature.

Hereinafter, the following examples and comparative examples are described in more detail.

Preparation of electrochromic device

WO 200nm thick was formed on an ITO transparent electrode by bar coating₃A Prussian blue film with a thickness of 200nm was formed on another ITO transparent electrode in the same manner. A boss (sealing portion) having a thickness of 100 μm was prepared, and after applying the electrolyte layer composition in the boss, the resultant was exposed to ultraviolet rays at 1100mJ/cm²To thereby prepare an electrochromic device of 10cm x 10 cm.

Preparation of electrolyte layer composition