CN110622062A

CN110622062A - Electrochromic device

Info

Publication number: CN110622062A
Application number: CN201880030780.0A
Authority: CN
Inventors: 吴云秀; 孙妏暎; 李仁会; 柳志昌; 朴镇庆; 李东建
Original assignee: LG Innotek Co Ltd
Current assignee: LG Innotek Co Ltd
Priority date: 2017-05-10
Filing date: 2018-04-13
Publication date: 2019-12-27
Also published as: WO2018208022A1

Abstract

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.

Description

Electrochromic device

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.

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.

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

Example 1

And (3) adding 9: 90: 1 weight ratio of at least one of polymerizable monomer, polymerizable oligomer and polymer, ionic liquid and photoinitiator represented by chemical formula 4, 1.03mol/L of LiTFSI (Lithium bis (trifluoromethanesulfonyl) imide) was added. At this time, at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer is a urethane acrylic oligomer and an acrylic monomer mixed in a weight ratio of 1:1, and the first ionic liquid represented by chemical formula 5 and the second ionic liquid represented by chemical formula 9 are mixed in a weight ratio of 4: 6.

Example 2

And (3) adding 9: 90: 1 weight ratio of the ionic liquid, the photoinitiator represented by chemical formula 4, at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, and 1.03mol/L of LiTFSI (lithium bis (trifluoromethanesulfonyl) imide) were added. At this time, at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer is a urethane acrylic oligomer and an acrylic monomer mixed in a weight ratio of 1:1, and the first ionic liquid represented by chemical formula 5 and the second ionic liquid represented by chemical formula 9 are mixed in a weight ratio of 5: 5.

Example 3

And (3) adding 9: 90: 1 weight ratio of the ionic liquid, the photoinitiator represented by chemical formula 4, at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, and 1.03mol/L of LiTFSI (lithium bis (trifluoromethanesulfonyl) imide) were added. At this time, at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer is a urethane acrylic oligomer and an acrylic monomer mixed in a weight ratio of 1:1, and the first ionic liquid represented by chemical formula 5 and the second ionic liquid represented by chemical formula 9 are mixed in a weight ratio of 6: 4.

Comparative example 1

And (3) adding 9: 90: 1 weight ratio of the ionic liquid, the photoinitiator represented by chemical formula 4, at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, and 1.03mol/L of LiTFSI (lithium bis (trifluoromethanesulfonyl) imide) were added. At this time, at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer is a urethane acrylate oligomer and an acrylic monomer mixed in a weight ratio of 1:1, and the first ionic liquid represented by chemical formula 5 and the second ionic liquid represented by chemical formula 9 are mixed in a weight ratio of 7: 3.

Comparative example 2

And (3) adding 9: 90: 1 weight ratio of the ionic liquid, the photoinitiator represented by chemical formula 4, at least one of a polymerizable monomer, a polymerizable oligomer, and a polymer, and 1.03mol/L of LiTFSI (lithium bis (trifluoromethanesulfonyl) imide) were added. At this time, at least one of the polymerizable monomer, the polymerizable oligomer, and the polymer is a urethane acrylic oligomer and an acrylic monomer mixed in a weight ratio of 1:1, and only the first ionic liquid represented by chemical formula 5 is used.

Comparative example 3

1M LiClO₄Dissolved in propylene carbonate.

Charge and discharge experiments of the electrochromic devices prepared by examples 1 to 3 and comparative examples 1 to 3 were performed. The first cycle is completed by the following method: starting from the initial voltage of 3V, after a process of coloring for 60sec with a voltage of-2V, a process of fading for 60sec with a voltage of 2V was performed. Then, the transmittance T (%) at the time of coloring and fading was measured by a UV-V spectrophotometer analysis device.

Table 1 shows the results of transmittance and time for coloring and fading measured after 10 cycles of driving, and table 2 shows the results of transmittance and time for coloring and fading measured after 2000 cycles of driving. Fig. 4 is a photograph of the electrolyte layer of example 3 after repeated driving, and fig. 5 is a photograph of the electrolyte layer of comparative example 1 after repeated driving.

TABLE 1

TABLE 2

Referring to tables 1 to 2, as shown in examples 1 to 3, when the first ionic liquid and the second ionic liquid were contained at weight ratios of 4:6, 5:5 and 6:4, that is, when 5 to 15 parts by weight of the second ionic liquid was contained with respect to 10 parts by weight of the first ionic liquid, the driving was possible even after 2000 cycles, but the driving was impossible in comparative examples 1 to 3 which deviate from such a numerical range. In particular, as shown in tables 1 to 2, when the first ionic liquid and the second ionic liquid are contained in a weight ratio of 5:5 and 6:4, that is, when 5 to 10 parts by weight of the second ionic liquid is contained with respect to 10 parts by weight of the first ionic liquid, the color change range is large and the average color change time is short as compared with example 1, as shown in examples 2 to 3.

In particular, as shown in examples 3, when the first ionic liquid and the second ionic liquid were contained at a weight ratio of 6:4, that is, when 5 to 8 parts by weight of the second ionic liquid was contained with respect to 10 parts by weight of the first ionic liquid, the color change range was large and the average color change time was short as compared with examples 1 to 2, as seen from tables 1 to 2.

As can be seen from fig. 4 to 5, as shown in example 3, when the first ionic liquid and the second ionic liquid were contained at a weight ratio of 6:4, the phenomenon of ionic gel breakage of the electrolyte layer did not occur, but as shown in comparative example 1, when the second ionic liquid was out of the range of 5 to 15 parts by weight with respect to 10 parts by weight of the first ionic liquid, the ionic gel was broken and transferred to the ITO transparent electrode side and diffused.

The composition of the first ionic liquid and the second ionic liquid contained in the electrolyte layer of the electrochromic device according to the embodiment of the present invention can be analyzed by IR analysis (InfraRed spectroscopy) or NMR (nuclear magnetic resonance) analysis, and the content can be analyzed by TGA analysis (thermogravimetric analysis).

On the other hand, since the first color-changing material layer 120 and the electrolyte layer 130 or the electrolyte layer 130 and the second color-changing material layer 140 have different polarities, the bonding force is low, and thus an air layer may exist at the interface between the layers. Similarly, since the first electrode portion 110 and the first color-changing material layer 120 or the second color-changing material layer 140 and the second electrode portion 150 have different polarities, the bonding force is low, and thus an air layer may exist at the interface between the layers.

The air layer existing at the interface between the layers plays a role of reducing the ion conductivity of the electrochromic device, and thus the color change speed, which is one of important properties of the electrochromic device, may be reduced.

In the embodiment of the invention, the buffer layer is added on the interface between the layers, thereby improving the bonding force between the layers. Hereinafter, the duplicate explanation will be omitted for the same contents as those explained in fig. 1 to 3.

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

While the first buffer layer 600 is disposed between the first color-changing material layer 120 and the electrolyte layer 130 and the second buffer layer 602 is disposed between the electrolyte layer 130 and the second color-changing material layer 140, the present invention is not limited to this, and only one of the first buffer layer 600 and the second buffer layer 602 may be disposed, as shown in fig. 6 (a) and 6 (b).

The first buffer layer 600 and the second buffer layer 602 can improve the bonding force and the adhesive force of the interface between the first color-changing material layer 120 and the electrolyte layer 130 and the interface between the electrolyte layer 130 and the second color-changing material layer 140, respectively.

According to an embodiment of the present invention, the first buffer layer 600 includes a first color-changing substance included in the first color-changing substance layer 120 and an electrolyte included in the electrolyte layer 130, and the second buffer layer 602 includes a second color-changing substance included in the second color-changing substance layer 140 and an electrolyte included in the electrolyte layer 130. Accordingly, the first buffer layer 600 and the second buffer layer 602 can reduce the polarity difference between the first color-changing material layer 120 and the electrolyte layer 130 and between the electrolyte layer 130 and the second color-changing material layer 140, respectively, thereby preventing air gaps at the interface and improving the bonding force and the adhesive force.

At this time, the content of the electrolyte contained in the first buffer layer 600 or the second buffer layer 602 may be 0.01 to 5 wt%, preferably 0.05 to 4 wt%, and more preferably 1 to 3 wt% in the first buffer layer 600 or the second buffer layer 602. When the content of the electrolyte in the first buffer layer 600 or the second buffer layer 602 is less than 0.01 wt%, the first buffer layer 600 or the second buffer layer 602 may not function to improve the binding force and the binding force at the interface between the first color-changing material layer 120 and the electrolyte layer 130 and the interface between the electrolyte layer 130 and the second color-changing material layer 140. Also, when the content of the electrolyte in the first buffer layer 600 or the second buffer layer 602 is greater than 5 wt%, the distance between the color-changing substances in the first buffer layer 600 or the second buffer layer 602 becomes long, possibly reducing the ionic conductivity improvement effect.

While the first buffer layer 600 is disposed between the first color-changing material layer 120 and the electrolyte layer 130 and the second buffer layer 602 is disposed between the electrolyte layer 130 and the second color-changing material layer 140, respectively, with reference to fig. 7 (a) and 7 (b), the present invention is not limited thereto, and only one of the first buffer layer 600 and the second buffer layer 602 may be disposed.

According to an embodiment of the present invention, the first buffer layer 600 includes a first color-changing material and a conductive polymer included in the first color-changing material layer 120, and the second buffer layer 602 includes a second color-changing material and a conductive polymer included in the second color-changing material layer 140. Accordingly, the first buffer layer 600 and the second buffer layer 602 can reduce the polarity difference between the first color-changing material layer 120 and the electrolyte layer 130 and between the electrolyte layer 130 and the second color-changing material layer 140, respectively, thereby preventing air gaps at the interface and improving the bonding force and the adhesive force.

The conductive polymer may be selected from CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-Ethylenedioxythiophene) polystyrene sulfonate), PEDOT-PANI (poly (3,4-Ethylenedioxythiophene) polyaniline), EDOT (Ethylenedioxythiophene, 3,4-Ethylenedioxythiophene) polyaniline), PEDOT (Ethylenedioxythiophene ), CNT (Carbon nanotube), PVDF (vinylidine fluoride, polyvinylidene fluoride), PEDOT: PPy, SBR resin.

Preferably, the conductive polymer may be selected from CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI. At least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate), and PEDOT-PANI functions as a matrix for moving (mobility) ions dispersed between the color-changing substances of the first buffer layer 600 or the second buffer layer 602 while connecting the interface between the first color-changing substance layer 120 and the electrolyte layer 130. In particular, at least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI has higher conductivity than other conductive polymers, and thus electrons between color-changing substances are easily moved, thereby increasing ion conductivity and increasing a color-changing speed. In addition, at least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI in the conductive polymer is easier to disperse compared with other conductive polymers, so that the conductive polymer can be coated on the surface of the color-changing substance in the buffer layer. This can provide an effect of improving the ion conductivity and the color change rate.

At this time, the content of the conductive polymer, for example, at least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate), and PEDOT-PANI, contained in the first buffer layer 600 or the second buffer layer 602 may be 0.01 to 5 wt%, preferably 0.05 to 4 wt%, and more preferably 1 to 3 wt% in the first buffer layer 600 or the second buffer layer 602. When the content of the conductive polymer in the first buffer layer 600 or the second buffer layer 602 is less than 0.01 wt%, the first buffer layer 600 or the second buffer layer 602 may not function to improve the bonding force and the adhesive force at the interface between the first color-changing material layer 120 and the electrolyte layer 130 and the interface between the electrolyte layer 130 and the second color-changing material layer 140. In addition, when the content of the conductive polymer in the first buffer layer 600 or the second buffer layer 602 is greater than 5 wt%, the distance between the color-changing substances in the first buffer layer 600 or the second buffer layer 602 may be increased, which may reduce the ionic conductivity improvement effect.

In the embodiments of fig. 6 to 7, the thickness of the first buffer layer 600 may be 0.01 to 20%, preferably 0.01 to 10%, and more preferably 0.01 to 5% of the thickness of the first color-changing material layer 120. Also, the thickness of the second buffer layer 602 may be 0.01% to 20%, preferably 0.01% to 10%, and more preferably 0.01% to 5% of the thickness of the second color change material layer 140. When the thickness of the first buffer layer 600 or the second buffer layer 140 is less than 0.01% of the thickness of the first color-changing material layer 120 or the second color-changing material layer 140, it is difficult to function as a buffer layer. That is, the first buffer layer 600 or the second buffer layer 602 hardly functions to improve the bonding force and the adhesion force of the interface between the first color-changing material layer 120 and the electrolyte layer 130 and the interface between the electrolyte layer 130 and the second color-changing material layer 140, and thus it is difficult to obtain the effects of increasing the ion conductivity and increasing the color-changing speed. When the thickness of the first buffer layer 600 or the second buffer layer 602 is greater than 20% of the thickness of the first color-changing material layer 120 or the second color-changing material layer 140, the distance over which ions need to travel becomes large, and the color-changing speed may be decreased.

While the third buffer layer 604 is disposed between the first electrode portion 110 and the first color-changing material layer 120 and the fourth buffer layer 606 is disposed between the second color-changing material layer 140 and the second electrode portion 150, respectively, with reference to fig. 8 (a) and 8 (b), the present invention is not limited thereto, and only one of the third buffer layer 604 and the fourth buffer layer 606 may be disposed.

The third buffer layer 604 and the fourth buffer layer 606 can improve the bonding force and the adhesive force of the interface between the first electrode part 110 and the first color-changing material layer 120 and the interface between the second color-changing material layer 140 and the second electrode part 150, respectively.

According to an embodiment of the present invention, the third buffer layer 604 includes a first color-changing substance included in the first color-changing substance layer 120 and a transparent conductive material included in the first electrode part 110, and the fourth buffer layer 606 includes a second color-changing substance included in the second color-changing substance layer 140 and a transparent conductive material included in the second electrode part 150. Therefore, the third buffer layer 604 and the fourth buffer layer 606 can reduce the polarity difference between the first electrode part 110 and the first color-changing material layer 120 and between the second color-changing material layer 140 and the second electrode part 150, respectively, thereby preventing air gaps at the interface and improving the bonding force and the adhesive force.

At this time, the content of the transparent conductive material included in the third buffer layer 604 or the fourth buffer layer 606 may be 0.01 to 5 wt%, preferably 0.05 to 4 wt%, and more preferably 1 to 3 wt% in the third buffer layer 604 or the fourth buffer layer 606. When the content of the transparent conductive material in the third buffer layer 604 or the fourth buffer layer 606 is less than 0.01 wt%, the third buffer layer 604 or the fourth buffer layer 606 cannot function to improve the bonding force and the adhesion force at the interface between the first electrode part 110 and the first color-changing material layer 120 and the interface between the second color-changing material layer 140 and the second electrode part 150. Further, when the content of the transparent conductive material in the third buffer layer 604 or the fourth buffer layer 606 is greater than 5 wt%, the distance between the color-changing substances in the third buffer layer 604 or the fourth buffer layer 606 becomes longer, and the ionic conductivity improvement effect may be reduced.

While the third buffer layer 604 is disposed between the first electrode portion 110 and the first color-changing material layer 120 and the fourth buffer layer 606 is disposed between the second color-changing material layer 140 and the second electrode portion 150 with reference to fig. 9 (a), the present invention is not limited thereto and only one of the third buffer layer 604 and the fourth buffer layer 606 may be disposed.

The third buffer layer 604 and the fourth buffer layer 606 can improve the bonding force and the adhesive force on the interface between the first electrode portion 110 and the first color-changing material layer 120 and the interface between the second color-changing material layer 140 and the second electrode portion 150, respectively.

According to an embodiment of the present invention, the third buffer layer 604 includes a first color-changing substance included in the first color-changing substance layer 120 and a conductive polymer included in the first electrode 110, and the fourth buffer layer 606 includes a second color-changing substance included in the second color-changing substance layer 140 and a conductive polymer included in the second electrode 150. Therefore, the third buffer layer 604 and the fourth buffer layer 606 reduce the polarity difference between the first electrode 110 and the first color-changing material layer 120 and between the second color-changing material layer 140 and the second electrode 150, respectively, thereby preventing air gaps at the interface and improving the bonding force and the adhesive force.

The conductive polymer may be selected from CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate), poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI. At least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate), and PEDOT-PANI functions to connect the interface between the first electrode part 110 and the first color-changing material layer 120 and the interface between the second color-changing material layer 140 and the second electrode part 150, and also functions as a matrix for moving (mobilization) ions dispersed between the color-changing materials of the third buffer layer 604 and the fourth buffer layer 606. That is, at least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate, poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI easily moves electrons between color-changing substances, thereby increasing ionic conductivity and increasing a color-changing speed.

At this time, the content of the conductive polymer, for example, at least one of CMC (carboxymethyl cellulose), poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (pdot-PSS), and PEDOT-PANI, contained in the third buffer layer 604 and the fourth buffer layer 606 may be 0.01 to 5 wt%, preferably 0.05 to 4 wt%, and more preferably 1 to 3 wt%. When the content of the conductive polymer in the third buffer layer 604 and the fourth buffer layer 606 is less than 0.01%, the third buffer layer 604 and the fourth buffer layer 606 cannot function to improve the bonding force and the adhesion force at the interface between the first electrode portion 110 and the first color-changing material layer 120 and the interface between the second color-changing material layer 140 and the second electrode portion 150. In addition, when the content of the conductive polymer in the third buffer layer 604 and the fourth buffer layer 606 is greater than 5%, the distance between the discolored substances in the third buffer layer 604 and the fourth buffer layer 606 may be increased, thereby reducing the effect of improving the ionic conductivity.

In the embodiments of fig. 8 to 9, the thickness of the third buffer layer 604 may be 0.01 to 20%, preferably 0.01 to 10%, and more preferably 0.01 to 5% of the thickness of the first color-changing material layer 120. Also, the thickness of the fourth buffer layer 606 may be 0.01% to 20%, preferably 0.01% to 10%, and more preferably 0.01% to 5% of the thickness of the second color change material layer 140. When the thickness of the third buffer layer 604 or the thickness of the fourth buffer layer 606 is less than 0.01% of the thickness of the first color-changing material layer 150 or the thickness of the second color-changing material layer 160, it is difficult to function as a buffer layer. That is, the third buffer layer 604 or the fourth buffer layer 606 hardly serves to improve the bonding force and the adhesion force at the interface between the first electrode part 110 and the first color-changing material layer 120 and the interface between the second color-changing material layer 140 and the second electrode part 150, and thus hardly provides effects of increasing ion conductivity and increasing a color-changing rate. When the thickness of the third buffer layer 604 or the thickness of the fourth buffer layer 606 is greater than 20% of the thickness of the first color-changing material layer 120 or the thickness of the second color-changing material layer 140, the distance over which ions need to move becomes large, and the color-changing speed may be decreased.

While the first buffer layer 600 is disposed between the first color-changing material layer 120 and the electrolyte layer 130 and the second buffer layer 602 is disposed between the electrolyte layer 130 and the second color-changing material layer 140 with reference to fig. 10, the present invention is not limited thereto and only one of the first buffer layer 600 and the second buffer layer 602 may be disposed. Further, the third buffer layer 604 is disposed between the first electrode portion 110 and the first color-changing material layer 120, and the fourth buffer layer 606 is disposed between the second color-changing material layer 140 and the second electrode portion 150 as an example, but the present invention is not limited thereto, and only one of the third buffer layer 604 and the fourth buffer layer 606 may be disposed. The same contents as those of fig. 6 to 9 will not be described repeatedly.

On the other hand, the first color changing material layer 120 and the second color changing material layer 140 include a solvent such as water, ethanol, butanol, methanol, etc., and the color changing material 10 dispersed in the solvent.

In this case, when the charge between the color-changing substances 10 and the movement of the particles are increased, the color-changing speed can be increased. For this reason, a matrix for improving charge and ion movement between color-changing substances may be added in the embodiment of the present invention.

According to an embodiment of the present invention, the color-changing substance layer may further include a conductive polymer for improving ion mobility between the color-changing substances.

Although fig. 11 illustrates that both the first color-changing material layer 120 and the second color-changing material layer 140 further include the conductive polymer 20, the present invention is not limited thereto, and only one of the first color-changing material layer 120 and the second color-changing material layer 140 may include the conductive polymer.

The conductive polymer may be selected from CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate), PEDOT-PANI (poly (3,4-ethylenedioxythiophene) polyaniline), EDOT (ethylenedioxythiophene), CNT (carbon nanotube), PVDF (polyvinylidene fluoride), PEDOT: PPy, and SBR resin.

Preferably, the conductive polymer may be selected from CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI.

The conductive polymer may also function as a matrix for moving (mobilization) ions between the color-changing substances dispersed in the first color-changing substance layer 120 or the second color-changing substance layer 140. In particular, at least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate) and PEDOT-PANI among the conductive polymers has higher conductivity than the other conductive polymers, and thus electrons between color-changing substances are easily moved, thereby increasing ion conductivity and increasing a color-changing speed. In addition, at least one of CMC (carboxymethyl cellulose), PEDOT-PSS (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate), and PEDOT-PANI among the conductive polymers is more easily dispersed in the first color-changing material layer 120 and the second color-changing material layer 140 than other conductive polymers, and thus can be applied to the surface of the color-changing material. This can provide an effect of improving the ion conductivity and the color change rate.

In particular, the color-changing substance dispersed in the first color-changing substance layer 120 or the second color-changing substance layer 140 serves not only to change the color simply but also to store ions. In this case, when the first color-changing material layer 120 or the second color-changing material layer 140 further contains a conductive polymer, the ion storage capacity of the conductive polymer is further increased, so that more ions can be stored and the buffer for the ions can be provided. Therefore, the color change speed can be improved.

Furthermore, the conductive polymer contained in the first color-changing material layer 120 or the second color-changing material layer 140 may also provide a function of a binder. Therefore, it is possible to improve the bonding force and the adhesive force in the interface between the first color-changing material layer 120 and the first electrode portion 110 or the electrolyte layer 130, and to improve the bonding force and the adhesive force in the interface between the second color-changing material layer 140 and the electrolyte layer 130 or the second electrode portion 150. When the bonding force and the adhesive force in the interface between layers are increased, air gaps on the interface can be prevented and thus ion conductivity and discoloration speed can be improved.

Fig. 12 is a graph comparing the performances of the electrochromic devices of comparative example 11 and example 11, and table 3 is a table showing the performances of the electrochromic devices of comparative example 11 and example 11.

Referring to FIG. 12, the change of the light transmittance T (%) with time(s) at a wavelength of 700nm was measured for the sample of comparative example 11 and the sample of example 11.

The sample of comparative example 11 contained WO as a negative electrode side color-changing substance₃Prussian blue as a positive electrode-side color-changing substance, the sample of example 11 contained WO as a negative electrode-side color-changing substance₃The positive electrode side coloring material contained 95 wt% of prussian blue, and the conductive polymer contained 5 wt% of CMC.

Referring to fig. 12 and table 3, it is understood that the reaction time at the light transmittance Δ T80% p. of the sample of example 11 is reduced and the reaction speed is improved.

TABLE 3

The electrochromic device and the electrochromic apparatus according to the embodiments of the present invention can be applied to various mirrors for vehicles, windows for buildings, display devices, ESL devices, and the like.

On the other hand, the electrochromic device according to the embodiment of the present invention can be applied to various applications (Application), and can also be applied to a display that requires a color change in a specific portion, such as an Electronic Shelf Label (ESL).

Referring to fig. 13 to 14, the electrochromic device 100 may be divided into an electrode region a1 and a dummy electrode region a2 by an electrode spacer G. The electrode region a1 is a region displayed in the form of characters, numerals, patterns, etc., and the dummy electrode region a2 may be a region displayed in the form of a background. The electrode region a1 may be used in combination with a conversion region, a display region, and the like as a region for displaying information, and the dummy electrode region a2 may be used in combination with a background region.

The electrode region a1 includes a plurality of divisional regions a1-1, a1-2, a.. ang.a 1-n, the plurality of divisional regions a1-1, a1-2, a.. ang.a 1-n are spaced apart from each other and can be independently driven. The electrode region a1 may expose various information according to a combination of decoloring and coloring of the plurality of divisional regions a1-1, a 1-2. For this, a plurality of divisional regions a1-1, a1-2, ·, a1-n may be arranged around the dummy electrode region a 2. That is, the dummy electrode region a2 may be surrounded by a plurality of divided regions a1-1, a1-2, a.., a1-n, or a plurality of divided regions a1-1, a1-2, a.., a1-n may be surrounded by the dummy electrode region a 2. Therefore, the information displayed by the plurality of divisional areas a1-1, a1-2,.. and a1-n can be clearly displayed due to the background of the dummy electrode area a 2.

At this time, each region extends to a wiring region W having a narrower width than each region, through which connection to the pad electrode (pad electrode)30 is possible. That is, each of the divisional areas a1-1, a1-2, ·, a1-n can be connected to the pad electrode 30 through a wiring portion extending from each of the divisional areas a1-1, a1-2, ·, a 1-n. Therefore, the plurality of divided regions a1-1, a1-2,. and a1-n may be used in combination with the plurality of electrode regions a1-1, a1-2,. and a 1-n.

For example, the width of the wiring region W extending from each divided region may be 1/3 to 1/8 of the width of each divided region. If the width of the wiring region W is smaller than 1/8, which is the width of each divided region, the bus bar electrode in the wiring region may be broken, and if it is larger than 1/3, the wiring region may be exposed when the divided regions are colored. In addition, the width of the wiring region W may be 0.2 times or more and 2 times or less, 0.4 times or more and 1.5 times or less, and 0.5 times or more and 1.2 times or less the width of the Mesh (Mesh) opening of the bus electrode. If the width of the wiring region W is less than 0.2 times the width of the Mesh opening of the bus electrode, the electrodes in the wiring region W are short-circuited to each other, the bus electrode cannot function, and if it is more than 2 times, the wiring region may be exposed when coloring the divided region. A1 may be referred to as an electrode section, and a wiring region for connecting a1 with the pad electrode 30 may be referred to as a wiring section.

Thus, the respective regions can undergo a color change reaction independently of each other. For example, it may be implemented that a color change reaction occurs only in the electrode region a1 and no color change reaction occurs in the dummy electrode region a2, or that color change reactions of the electrode region a1 and the dummy electrode region a2 occur independently, or that color change reactions of the plurality of divided regions a1-1, a1-2, a. When the discoloration reactions implemented as the electrode region a1 and the dummy electrode region a2 occur independently, the dummy electrode region a2 may be an electrode region. Therefore, the electrode spacer G may be formed between the plurality of electrode regions a1, a 2.

On the other hand, the line width of the electrode spacing portion (groove) G is realized differently depending on the width or Pitch (Pitch) of the Mesh opening of the bus electrode. The line width of the electrode spacer G may be 0.1 times or more and 150um or less, preferably 0.2 times or more and 120um or less, and more preferably 0.2 times or more and 90um or less of the width of the Mesh (Mesh) opening of the bus electrode. When the line width of the electrode spacer G is less than 0.1 times the width of the opening of the bus electrode Mesh (Mesh), there is a possibility that the electrode region a1 and the dummy electrode region a2 will not be electrically short-circuited, and when the line width of the electrode spacer G is more than 150 μm, it may be difficult to perform precise processing of the electrode region a 1. In addition, when the electrode spacing portion G is formed by laser processing, the line width of the electrode spacing portion G may be different according to laser processing capability.

Further, the pad electrode 30 may be disposed at one end of the first electrode portion 110, and the pad electrode 30 may be disposed in contact with the first electrode portion 130.

Referring to fig. 15, an electrochromic device 1500 may include: a housing 1510; a circuit board 1520 disposed within the housing 1510; and an electrochromic device 100 connected with the circuit board 1520 through a connector 1530. As shown in fig. 15 (a), the electrochromic device 100 may be mounted in the case 1510 together with the circuit board 1520, or, as shown in fig. 15 (b), the circuit board 1520 and the connector 1530 may be mounted in the case 1530 with a part of the area of the electrochromic device 100, and the remaining area of the electrochromic device 100 is exposed to the outside of the case 1510.

The connector 1530 may be a flexible circuit board (FPCB) or a Flexible Flat Cable (FFC), but is not limited thereto.

The electrochromic device of fig. 15 (a) may be attached to a shelf, and the electrochromic device of fig. 15 (b) may be hung from the shelf or a ceiling. As shown in fig. 15 (b), when a Flexible (Flexible) electrochromic device is used for the electrochromic apparatus, an effect like Paper (Paper) can be achieved, thereby enabling a sense of familiarity to consumers.

The electrochromic device of the embodiment of the present invention may be applied to an electronic shelf label, which may be variously used in a market or the like as a device for displaying information such as price information, memory symbols (symbols), promotional images, bar codes, commodity names, commodity images, origins, and the like.

The server 3100 is a place where commodity information is stored, and the server 3100 can form a communication channel with the electronic shelf label via the gateway 3200 and the transmitter 3300. The server 3100 and the gateway 3200 and the transmitter 3300 may be connected via a wired network such as ethernet or a wireless network such as Wi-Fi.

The transmitter 3300 and the electronic shelf label 1500 may be connected via a wireless network such as Wi-Fi, bluetooth, RF, etc. The transmitter 3300 may receive the merchandise information from the server 3100 and transmit to the electronic shelf label 1500, and transmit power to the electronic shelf label 1500 according to the operation mode.

The electronic shelf label 1500 may include a control section, a communication module, a storage section, and a display section. The electronic shelf label 1500 may further include a battery therein. Alternatively, the electronic shelf label 1500 may be provided with a wireless power charging module so as to be wirelessly charged. The control part can control the communication module to communicate and display the product information received by the communication module on the display part. In addition, when power is transmitted from the transmitter 3300, power may be received, and a signal may be converted into a direct current voltage and the voltage may be supplied to the wireless power charging module. The storage unit stores data displayed on the display unit. The communication module may receive the goods information from the transmitter or may receive power from the transmitter. The display unit is used for displaying the commodity information received from the control unit. The display portion may be an electrochromic device.

The present invention has been described above with reference to the preferred embodiments thereof, and various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present invention as set forth in the appended claims.

Claims

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,

3. The electrochromic device according to claim 2,

4. The electrochromic device according to claim 3,

5. The electrochromic device according to claim 4,

6. The electrochromic device according to claim 2,

7. The electrochromic device according to claim 6,

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;

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

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

a second substrate disposed above the second electrode,