KR102208385B1 - Solid electrolyte and Light-transmittance variable panel and display device including the same - Google Patents

Abstract

The present invention provides a solid electrolyte having excellent ionic conductivity, transmittance, and flexibility, including first and second oligomers polymerized by a thiolene reaction, and a variable transmittance panel and display device including the same.

Description

Solid electrolyte and light-transmittance variable panel and display device including the same}

The present invention relates to a display device, and to a solid electrolyte having high transmittance, high ionic conductivity, and high flexibility, and a variable light transmission panel and display device including the same.

As the information society develops, demands for display devices for displaying images are increasing in various forms, and in recent years, liquid crystal displays (LCDs), plasma display panels (PDPs), Various flat display devices such as an organic light emitting diode display device (OLED) are being used.

Among these flat panel displays, liquid crystal displays and organic light emitting diode displays are widely used.

A liquid crystal display device displays an image using optical anisotropy and polarization properties of liquid crystal molecules. For example, in a liquid crystal display, a pixel electrode and a common electrode are alternately arranged on a first substrate, and a liquid crystal layer including liquid crystal molecules is interposed between a second substrate facing the first substrate.

Meanwhile, the organic light emitting device display device emits light by forming an organic light emitting layer between the anode and the cathode. Holes injected from the anode and electrons injected from the cathode combine in the organic light-emitting layer to form excitons, and excitons transition from the excited state to the ground state to emit light.

Recently, interest in a transparent display device having a transparent surface and transmitting light is increasing. Such a transparent display device is applied to a so-called smart window.

However, since the transparent display device does not have a black state, the contrast ratio is lowered and the image visibility is not good. To improve this, a method of using a light shielding plate on one surface of a display panel has been proposed.

For example, when a voltage is applied to an electrode, an electrochromic element capable of adjusting transmittance by an oxidation-reduction reaction of an electrochromic material is used as a light shielding plate.

The electrochromic device includes two substrates on which electrodes are formed, and an electrochromic layer formed between the two substrates, and the electrochromic layer is composed of an electrolyte layer and an electrochromic material layer.

Conventionally, liquid electrolytes have been mainly used. However, when a liquid electrolyte is used, an electrode material is corroded, an organic solvent is volatilized, and a problem of leakage of the liquid electrolyte occurs.

In order to solve the problem of such a liquid electrolyte, a solid electrolyte has been proposed. The solid electrolyte includes a polymer and a lithium salt that dissociates in the polymer. Polymers contain polar elements such as oxygen and nitrogen, and these elements form a polymer-lithium ion complex by coordinating bonds with dissociated lithium ions.

The most widely studied solid electrolyte material is composed of polyethylene oxide (PEO) and lithium salt. Such a PEO-based polymer electrolyte has an ionic conductivity of 10 ^-5 S/cm or more at a temperature above the melting point of PEO (67 to 72 degrees), but has an ionic conductivity of approximately 10 ^-8 S/cm at room temperature. That is, in the case of a crystalline polymer electrolyte such as PEO, the ionic conductivity is very low at a temperature below the melting point of the polymer.

In addition, a solid electrolyte in which PEO (polyethylene oxide) and PEG (polyethylene glycol) are mixed has been introduced, but since the ionic conductivity is not high and the viscosity is too high, there is a problem that a long vacuum drying process is required.

The solid electrolyte used in the electrochromic device must be transparent and have high ionic conductivity. In addition, the flexibility (flexibility) must be high to prevent damage due to external impact.

However, when a polymer electrolyte such as PEO is used, it has too low ionic conductivity at room temperature and the transmittance is also poor. In addition, since the flexibility is not good, there is a problem that damage due to external impact occurs.

The present invention aims to solve problems such as corrosion of electrode materials, volatilization of organic solvents, and liquid leakage that occur when a liquid electrolyte is used, and problems of low ionic conductivity, transmittance, and flexibility in a conventional solid electrolyte.

In order to solve the above problems, the present invention provides a solid electrolyte comprising an ionic salt, a polymer matrix formed by polymerization of a first oligomer represented by the following formula 1 and a second oligomer represented by the following formula 2 do.

[Formula 1]

[Formula 2]

(M1+m2=1 in Formula 1, and m3+m4=1 in Formula 2.)

In the solid electrolyte of the present invention, the polymer matrix is represented by the following formula and x+y=1.

In the solid electrolyte of the present invention, x may be equal to or greater than y.

In the solid electrolyte of the present invention, the ionic salt may be a lithium salt.

In another aspect, the present invention provides a first and second substrate facing each other, a first transparent electrode disposed on the first substrate, a second transparent electrode disposed on the second substrate, and the first It provides a variable transmittance panel comprising an electrochromic particle layer positioned between the transparent and the second transparent electrode, and a solid electrolyte layer including the above-described solid electrolyte positioned between the second transparent electrode and the electrochromic particle layer.

In another aspect, the present invention provides a display device including the aforementioned variable transmittance panel and a display panel positioned at one side of the variable transmittance panel and including a display portion and a transparent portion.

The solid electrolyte of the present invention is a first oligomer in which an acrylate moiety and a polyethylene glycol moiety are bonded to a poly(silsesquioxane) back-bone. By including a solid polymer formed by polymerization of a second oligomer having a thiolene (-SH) moiety bonded to the polysilsesquioxane backbone, ionic conductivity, transmittance, and flexibility are improved.

In other words, the ionic conductivity is greatly increased by the first oligomer, and free-volumne is formed in the polymer by polymerization of the first and second oligomers, thereby increasing flexibility, and polymerization by the first and second oligomers. Polymers have high permeability.

Accordingly, the solid electrolyte containing the above-described solid polymer and ionic salt has high ionic conductivity and transmittance while solving problems such as liquid leakage in the liquid electrolyte. In addition, since the flexibility is improved, the solid electrolyte layer is prevented from being damaged by an external impact or the like, and can be used in a flexible display device.

In addition, the transmittance variable panel using the solid electrolyte and electrochromic particles of the present invention improves the transmittance and reduces the driving voltage.

In addition, power consumption of a display device including a variable transmittance panel may be reduced, and visibility and contrast ratio may be improved.

1A to 1D are photographs for explaining the transmittance and haze of a solid electrolyte.
2A to 2C are photographs for explaining the flexibility of a solid electrolyte.
3 is a schematic cross-sectional view of a variable transmittance panel according to an embodiment of the present invention.
4 is a schematic cross-sectional view of a display device including a variable transmittance panel according to an exemplary embodiment of the present invention.
5 is a schematic cross-sectional view of the display panel of FIG. 4.

Hereinafter, a preferred embodiment according to the present invention will be described with reference to the drawings.

The solid electrolyte of the present invention includes a polymer matrix formed by polymerization of a first oligomer represented by Formula 1 below and a second oligomer represented by Formula 2 below, and an ionic salt.

The ionic salt may be a lithium (Li) salt, for example, LiPF ₆ , LiF, LiBR ₄ (R is a phenyl group or an alkyl group), LiSbF ₆ , LiAsF6, LiBF ₄ , LiClO ₄ , LiCF ₃ SO ₃ , LiN(CF ₃ SO ₂ ) ₂ , LiC(CF ₃ SO ₂ ) ₃ , LiC ₆ F ₉ S ₃ , LiC ₈ F ₁₇ SO ₃ , LiAlCl _{4 It} may be any one of, but is not limited thereto.

[Formula 1]

[Formula 2]

In Formula 1, m1+m2=1, and in Formula 2, m3+m4=1. Also, m1=(2/3)m2 and m3=(2/3)m4 may be used.

That is, the first oligomer has a structure in which an acrylate moiety and a polyethylene glycol moiety are bonded to a poly(silsesquioxane) back-bone, The second oligomer has a structure in which a thiolene (-SH) moiety is bonded to a polysilsesquioxane backbone.

The ionic conductivity is greatly improved by the polyethylene glycol moiety of the first oligomer, and the first and second oligomers become a copolymer by the reaction of the acrylate moiety and the thiolene moiety to form a free volume (fee-volumne). The flexibility is improved. In addition, since the benzene ring (phenyl) is substituted with silsesquioxane, the degree of freedom of the molecule is increased, and the flexibility is further improved.

A copolymer formed by a thiolene reaction between the first oligomer of Formula 1 and the second oligomer of Formula 2 may be represented by the following Formula 3.

[Chemical Formula 3]

In Chemical Formula 3, x+y=1.

As described above, the solid electrolyte of the present invention has advantages in terms of ionic conductivity, transmittance, and flexibility, including an ionic salt such as a lithium salt and a copolymer formed by polymerizing an oligomer of Formula 1 and an oligomer of Formula 2 .

The solid electrolyte layer of the present invention is based on an electrolyte solution (electrolyte composition) containing a first oligomer of Formula 1, a second oligomer of Formula 2, an ionic salt, and a photoinitiator or/and a thermal initiator. It is formed by coating on and curing.

The electrolyte composition may further include a plasticizer. For example, plasticizers of carbonate series (propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, methylethyl carbonate) and nitrile series (acetonitrile, benzonitrile, acrylonitrile, propionitrile) can be used.

Accordingly, the solid electrolyte layer includes a copolymer of Formula 3 in which the first oligomer and the second oligomer are polymerized, and an ionic salt.

[Preparation of solid electrolyte layer]

[Experimental Example]

A sol solution in which the oligomer of Formula 1 and/or the oligomer of Formula 2 are mixed was stirred with a propylene carbonate (PC) solution containing 1.5M Li salt in a 3:7 mass ratio. Thereafter, an electrolyte solution was prepared by adding a TPO photoinitiator (2,4,6-Trimethylbenzoyl-diphenyl-phosphineoxide) at a mass ratio of 0.3% to the oligomer mixture.

Thereafter, the electrolyte solution was coated and cured by irradiation with light of 1050 mJ/cm 2, thereby forming a solid electrolyte layer.

[Experimental Example 1]

An electrolyte solution was prepared using only the oligomer of Formula 2 without the oligomer of Formula 1, and a solid electrolyte layer was formed.

[Experimental Example 2]

An electrolyte solution was prepared using both the oligomer of Formula 1 and the oligomer of Formula 2, and a solid electrolyte layer was formed. (Mass ratio: Formula 1 oligomer <Formula 2 oligomer)

[Experimental Example 3]

An electrolyte solution was prepared using both the oligomer of Formula 1 and the oligomer of Formula 2, and a solid electrolyte layer was formed. (Mass ratio: Formula 1 oligomer = Formula 2 oligomer)

[Experimental Example 4]

An electrolyte solution was prepared using both the oligomer of Formula 1 and the oligomer of Formula 2, and a solid electrolyte layer was formed. (Mass ratio: Formula 1 oligomer> Formula 2 oligomer)

[Experimental Example 5]

An electrolyte solution was prepared using only the oligomer of Formula 1 without the oligomer of Formula 2, and a solid electrolyte layer was formed.

Table 1 shows the ionic conductivity according to the composition of the electrolyte layer formed through Experimental Examples 1 to 5.

As shown in Table 1, when the mass ratio of the oligomer of Formula 1 is equal to or greater than the mass ratio of the oligomer of Formula 2 (Experimental Examples 3 and 4), the ionic conductivity increases.

As described above, since the polyethylene glycol moiety substituted with the oligomer of Formula 1 contributes to the ionic conductivity, a solid electrolyte layer including only the oligomer of Formula 2 was formed without the oligomer of Formula 1 (Experimental Example 1) or the formula of a small mass ratio When a solid electrolyte layer including the oligomer of 1 is formed (Experimental Example 2), the solid electrolyte layer has low ionic conductivity.

In addition, when a solid electrolyte layer is formed including only the oligomer of Formula 1 without the oligomer of Formula 2 (Experimental Example 5), the ionic conductivity decreases and the flexibility deteriorates.

Accordingly, the solid electrolyte of the present invention includes both the oligomer of Formula 1 and the oligomer of Formula 2, the mass ratio of the oligomer of Formula 1 is made from a composition that is equal to or greater than the mass ratio of the oligomer of Formula 2, and has high ionic conductivity. That is, in Formula 3, x may be equal to or greater than y. (x≥y)

[Comparative Example 1]

LiClO ₄ 2g, PEO (polyethyleneoxide) (Mw 60k) 1.9g, PEG (polyethylene glycol) (MW 4000) 1.9g, methanol 4.8g were stirred at a temperature of 45 ~ 50 °C for 12 hours to prepare a solid electrolyte solution.

The electrolyte solution was dried in a vacuum to form an electrolyte layer. At this time, a vacuum drying process of 2 hours was required for forming the electrolyte layer.

[Comparative Example 2]

After mixing a propylene carbonate solution containing 1.5M Li salt and trimethylolpropane ethoxylate triacrylate at a mass ratio of 85:15, an electrolyte solution was prepared by including a TPO photoinitiator in an amount of 0.3 to 1% by weight relative to the oligomer.

The electrolyte solution was coated, and an electrolyte layer was formed by irradiating light of 1100 mJ/cm 2.

[Comparative Example 3]

After mixing a propylene carbonate solution containing 1.5M Li salt, methoxypolyethylene glycol monoacrylate, and polyethylene glycol dimethacylate at a mass ratio of 6:3:1, an electrolyte solution was prepared by including a TPO photoinitiator in an amount of 0.3 to 1% by weight relative to the oligomer.

The electrolyte solution was coated, and an electrolyte layer was formed by irradiating light of 1300 mJ/cm 2.

The ionic conductivity (room temperature), transmittance, haze, and radius of curvature of the electrolyte layers prepared through Experimental Example 4 and Comparative Examples 1 to 3 were measured, and the measurement results are shown in Table 2.

In addition, photographs showing the transmittance and haze characteristics of Experimental Example 4 and Comparative Examples 1 to 3 are shown in FIGS. 1A to 1D, and the radius of curvature of each of Experimental Example 4, Comparative Example 2, and Comparative Example 3, That is, pictures showing flexibility are shown in FIGS. 2A to 2C. In the case of Comparative Example 1, it was impossible to measure the radius of curvature due to the gel state.

As shown in Table 2, FIGS. 1A to 1D, and FIGS. 2A to 2C, the solid electrolyte comprising a copolymer formed by polymerizing an oligomer of Formula 1 and an oligomer of Formula 2 as in the present invention has high ionic conductivity. And has advantages in terms of transmittance, haze and flexibility.

3 is a schematic cross-sectional view of a variable transmittance panel according to an embodiment of the present invention.

As shown in FIG. 3, the variable transmittance panel 100 according to the embodiment of the present invention includes first and second substrates 110 and 120 facing each other, and first and second substrates 110 and 120. An electrochromic layer 140 disposed between the electrochromic particles 142 and a solid electrolyte 144, and a first transparent electrode 130 disposed between the first substrate 110 and the electrochromic layer 140 ), and a second transparent electrode 150 positioned between the second substrate 120 and the electrochromic layer 140.

Each of the first substrate 110 and the second substrate 120 may be made of glass or plastic. For example, each of the first substrate 110 and the second substrate 120 may be made of polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).

Each of the first transparent electrode 130 and the second transparent electrode 150 is made of a transparent conductive material. For example, each of the first transparent electrode 130 and the second transparent electrode 150 is indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). Can be made of. The variable transmittance panel of the present invention is formed of a transparent conductive material because the transmittance must be high in the transmission mode. Unlike this, when formed of a low-resistance metal material such as aluminum, it may have a thin thickness so that light can be transmitted.

The electrochromic layer 140 is located between the first and second substrates 110 and 120, that is, between the first and second transparent electrodes 130 and 150, and the electrochromic particles 142 and the solid electrolyte 144 Includes.

The electrochromic particles 142 include a core (not shown) and a shell (not shown) surrounding the core (not shown).

The core (not shown) may be made of a dielectric material. For example, the core may be made of indium-tin-oxide (ITO) or titanium oxide (TiO2).

The shell (not shown) is made of an electrochromic material and is discolored by an oxidation-reduction reaction when a voltage is applied, so that the transmittance using the electrochromic layer 140 can be varied.

The solid electrolyte 144 includes an ionic salt, which is an ion conductor, and a polymer matrix.

The ionic salt may be a lithium (Li) salt, for example, LiPF ₆ , LiF, LiBR ₄ (R is a phenyl group or an alkyl group), LiSbF ₆ , LiAsF6, LiBF ₄ , LiClO ₄ , LiCF ₃ SO ₃ , LiN(CF ₃ SO ₂ ) ₂ , LiC(CF ₃ SO ₂ ) ₃ , LiC ₆ F ₉ S ₃ , LiC ₈ F ₁₇ SO ₃ , LiAlCl _{4 It} may be any one of, but is not limited thereto.

The polymer matrix is a copolymer formed by polymerizing an oligomer of Formula 1 and an oligomer of Formula 2, that is, a polymer of Formula 3. That is, in the solid electrolyte 144 of the present invention, an acrylate moiety and a poly(ethylene)glycol moiety are contained in a polysilsesquioxane (poly(silsesquioxane)) back-bone. And a copolymer formed by polymerization of a first oligomer having a bonded structure and a second oligomer having a structure in which a thiolene (-SH) moiety is bonded to a polysilsesquioxane backbone.

As described above, the solid electrolyte of the present invention has advantages in terms of ionic conductivity, transmittance, and flexibility, including an ionic salt such as a lithium salt and a copolymer formed by polymerizing an oligomer of Formula 1 and an oligomer of Formula 2 .

In addition, by forming the solid electrolyte 144 using an electrolyte solution containing the formula 1 oligomer having a mass ratio equal to or greater than the mass ratio of the formula 2 oligomer, it has a greater advantage in terms of ionic conductivity and flexibility.

The variable transmittance panel 100 having this configuration has a transmissive state or a blocked state by application of a voltage.

That is, when no voltage is applied to the first and second transparent electrodes 130 and 150, since the electrochromic particles 142 are transparent, the transmittance variable panel 100 transmits light. On the other hand, when a voltage is applied to the first and second transparent electrodes 130 and 150, a shell (not shown) made of an electrochromic material is discolored and the transmittance variable panel 100 blocks light.

At this time, since the solid electrolyte 144 has high ionic conductivity, the variable transmittance panel 100 of the present invention has a fast response speed.

In addition, since the solid electrolyte 144 has a high transmittance, the transmittance of the variable transmittance panel 100 is also improved. In addition, since the solid electrolyte 144 has excellent flexibility, it is possible to prevent damage to the variable transmittance panel 100 and can be used in a flexible display device.

As described above, the transmittance variable panel 100 of the present invention varies the transmittance depending on whether or not a voltage is applied, and it is applied to a so-called transparent display device as described below to improve visibility and contrast ratio of the transparent display device.

4 is a schematic cross-sectional view of a display device including a variable transmittance panel according to an exemplary embodiment of the present invention.

4, the display apparatus 200 includes a transparent display panel 210 and a variable transmittance panel 220 positioned at one side of the transparent display panel 210.

The transparent display panel 210 includes a plurality of pixels, and each pixel includes a display unit 212, a circuit unit 214 and a transparent unit 216. The display unit 212 is driven by a voltage or signal supplied through the circuit unit 214 to display an image. The transparent display panel 210 may be a liquid crystal panel or a light emitting diode panel.

The case where the transparent display panel 210 is a light emitting diode panel will be briefly described.

Referring to FIG. 5, which is a schematic cross-sectional view of the display panel of FIG. 4, the transparent display panel 210 includes a third substrate 301 and a fourth substrate 302 facing each other, and includes third and fourth substrates. A display element (not shown) is formed between the 301 and 302, and the display element is a light emitting diode D.

Each of the third substrate 301 and the second substrate 302 may be made of glass or plastic. For example, each of the third substrate 301 and the second substrate 302 may be made of polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).

A gate line (not shown) and a data line (not shown) are formed on the third substrate 301 to cross each other to define the pixel region P, and are parallel to the gate line (not shown) or the data line (not shown). Power wiring (not shown) spaced apart is formed. The display portion 212, the driver 214, and the transparent portion 216 are defined in each pixel area P.

A switching thin film transistor (not shown) is formed in each pixel region P at the intersection of the gate line (not shown) and the data line (not shown).

In addition, it is connected to a switching thin film transistor (not shown) and a power wiring (not shown), and a driving thin film transistor DTr is formed.

The driving thin film transistor DTr includes a semiconductor layer 310, a gate electrode 320, and source and drain electrodes 331 and 333. The switching thin film transistor may have a structure similar to the driving transistor DTr.

The semiconductor layer 310 includes a channel region CR and a source region and drain regions SR and DR positioned on both sides of the channel region CR. The semiconductor layer 310 may be made of polysilicon.

Meanwhile, a buffer layer (not shown) may be formed between the semiconductor layer 310 and the third substrate 301.

On the semiconductor layer 310, a gate insulating film 315 is formed. The gate insulating layer 315 may be made of an inorganic insulating material such as silicon oxide or silicon nitride.

In addition, a gate electrode 320 is formed on the gate insulating layer 315 to correspond to the channel region CR. The gate electrode 320 may be made of a low-resistance metal material such as copper or aluminum.

On the gate electrode 320, an interlayer insulating film 325 is formed. A semiconductor contact hole 335 exposing each of the source region SR and the drain region DR may be formed in the interlayer insulating layer 225 and the gate insulating layer 315. The interlayer insulating layer 325 may be made of an inorganic insulating material such as silicon oxide or silicon nitride.

Source and drain electrodes 331 and 333 are formed on the interlayer insulating film 325. The source and drain electrodes 231 and 233 come into contact with the source and drain regions SR and DR of the semiconductor layer 310 through corresponding semiconductor contact holes 235, respectively.

A protective layer 340 may be formed on the source and drain electrodes 331 and 333. The protective layer 340 may be made of an inorganic insulating material such as silicon oxide or silicon nitride, or an organic insulating material such as photoacrylic. A drain contact hole 341 exposing the drain electrode 333 is formed in the protective layer 340.

The light emitting diode D is positioned on the protective layer 340 and is electrically connected to the driving thin film transistor DTr through the drain contact hole 341.

In the foregoing, a case in which a transistor using the semiconductor layer 310 made of crystalline silicon is formed has been exemplified. As another example, a transistor having an inverted staggered structure using amorphous silicon as a semiconductor layer may be used. As another example, an oxide transistor using an oxide semiconductor may be used.

Also, although not shown, a storage capacitor is formed in each pixel area P.

The light emitting diode D may include first and second electrodes 351 and 353 and an organic light emitting layer 352 formed between the first and second electrodes 351 and 353.

Here, the first and second electrodes 351 and 353 are configured to have a transparent characteristic. In this regard, the first and second electrodes 251 and 253 may be formed of a transparent conductive material. For example, one of oxide-based transparent conductive materials such as ITO, IZO, GZO, and IGZO may be used. At this time, one of the first and second electrodes 351 and 353 is an anode and the other is a cathode. The anode is made of a material having a relatively large work function value, and the cathode is made of a material having a relatively small work function value.

The first electrode 351 is connected to the drain electrode 333 of the driving thin film transistor DTr through the drain contact hole 341 and is patterned in units of the pixel region P. The second electrode 353 is integrally formed to correspond to the entire pixel area P of the display panel 310 in FIG. 5.

Meanwhile, on the first electrode 351, a bank 360 having an opening in each pixel region P may be formed. Such banks 360 serve to distinguish pixel regions P adjacent to each other.

An organic emission layer 352 is formed for each pixel area P corresponding to the opening of the bank 360. The organic light-emitting layer 352 functions to emit light by a combination of holes and electrons supplied from the first and second electrodes 351 and 353.

The organic light-emitting layer 352 may include a light-emitting material layer that substantially emits light. Meanwhile, in order to increase luminous efficiency, the organic light emitting layer 352 may have a multilayer structure. For example, the organic light emitting layer may further include a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer in addition to the light emitting material layer.

The light emitting diode D having the above-described configuration generates light having a corresponding luminance according to a signal applied to the gate electrode 320 of the driving thin film transistor DTr.

In addition, the fourth substrate 302 is an encapsulation substrate and covers the driving thin film transistor DTr. Although not shown, a barrier layer for preventing penetration of moisture or the like may be formed between the fourth substrate 302 and the driving thin film transistor DTr.

In FIG. 5, a region in which a driving element such as a driving thin film transistor DTr is formed corresponds to a driving unit (214 in FIG. 4 ), and a region in which the light emitting diode D is formed corresponds to the display unit (212 in FIG. 4 ). Meanwhile, a driving element and a display element are not formed in the transparent portion (216 in FIG. 4), and light is transmitted. Also, the display unit 212 and the driving unit 214 may overlap each other.

Referring to FIG. 4 again, the transmittance variable panel 220 is positioned between the first and second substrates 232 and 234 facing each other, and the first and second substrates 232 and 234 and electrochromic particles ( An electrochromic layer 240 including 242 and a solid electrolyte 244, a first transparent electrode 230 positioned between the first substrate 232 and the electrochromic layer 240, and a second substrate 234 ) And a second transparent electrode 250 positioned between the electrochromic layer 240.

Each of the first substrate 232 and the second substrate 234 may be made of glass or plastic. For example, each of the first substrate 232 and the second substrate 234 may be made of polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).

4 and 5, the first substrate 232 of the variable transmittance panel 220 and the fourth substrate 302 of the display panel 210 are shown to have the same configuration, but different substrates are used and they are attached. Thus, the variable transmittance panel 220 and the display panel 210 may be stacked.

Each of the first transparent electrode 230 and the second transparent electrode 250 is made of a transparent conductive material. For example, each of the first transparent electrode 230 and the second transparent electrode 250 may be made of ITO.

The electrochromic layer 240 is located between the first and second substrates 232 and 234, that is, between the first and second transparent electrodes 230 and 250, and the electrochromic particles 242 and the solid electrolyte 244 Includes.

The electrochromic particles 242 include a core and a shell. The core may be made of a dielectric material, for example, the core may be made of indium-tin-oxide (ITO) or titanium oxide (TiO2). In addition, the shell is made of an electrochromic material and is discolored by an oxidation-reduction reaction when a voltage is applied, so that the transmittance using the electrochromic layer 240 is variable.

The solid electrolyte 244 includes an ionic salt and a polymer matrix.

The ionic salt may be a lithium (Li) salt, for example, LiPF ₆ , LiF, LiBR ₄ (R is a phenyl group or an alkyl group), LiSbF ₆ , LiAsF6, LiBF ₄ , LiClO ₄ , LiCF ₃ SO ₃ , LiN(CF ₃ SO ₂ ) ₂ , LiC(CF ₃ SO ₂ ) ₃ , LiC ₆ F ₉ S ₃ , LiC ₈ F ₁₇ SO ₃ , LiAlCl _{4 It} may be any one of, but is not limited thereto.

The polymer matrix is a copolymer formed by polymerizing an oligomer of Formula 1 and an oligomer of Formula 2, that is, a polymer of Formula 3. That is, in the solid electrolyte 144 of the present invention, an acrylate moiety and a poly(ethylene)glycol moiety are contained in a polysilsesquioxane (poly(silsesquioxane)) back-bone. And a copolymer formed by polymerization of a first oligomer having a bonded structure and a second oligomer having a structure in which a thiolene (-SH) moiety is bonded to a polysilsesquioxane backbone.

The variable transmittance panel 220 having such a configuration has a transmissive state or a blocked state by application of a voltage.

That is, in a state in which a voltage is not applied to the first and second transparent electrodes 230 and 250, since the electrochromic particles 242 are transparent, the transmittance variable panel 220 transmits light. On the other hand, when a voltage is applied to the first and second transparent electrodes 230 and 250, the shell of the electrochromic particles 242 is discolored and the transmittance variable panel 220 blocks light.

In other words, in a state in which no voltage is applied to the first and second transparent electrodes 230 and 250, since the electrochromic particles 142 have a transparent state, the transmittance variable panel 220 enters the transmission mode and is transparent through Light from the portion 216 is transmitted.

However, when a voltage is applied to the first and second transparent electrodes 230 and 250, the electrochromic particles 142 are discolored, and thus the variable transmittance panel 220 enters a blocking mode to block light.

Accordingly, the display device 200 of the present invention including the variable transmittance panel 220 is used as a so-called transparent display device.

As described above, as described above, the solid electrolyte of the present invention includes an ionic salt such as a lithium salt, and a copolymer formed by polymerizing an oligomer of Formula 1 and an oligomer of Formula 2, including ionic conductivity, transmittance and flexibility. It has an advantage in terms of

In addition, by forming the solid electrolyte 144 using an electrolyte solution containing the formula 1 oligomer having a mass ratio equal to or greater than the mass ratio of the formula 2 oligomer, it has a greater advantage in terms of ionic conductivity and flexibility.

Accordingly, in the display device 200 including the variable transmittance panel 220 of the present invention, the speed of changing the transmission mode and the blocking mode is increased. Also, since the variable transmittance panel 220 has a high transmittance, the visibility and contrast ratio of the display device 200 are improved.

In addition, since the variable transmittance panel 220 has high flexibility, the display device 200 may be manufactured to have flexible characteristics.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the following claims. You will understand that you can do it.

100, 220: variable transmittance panel 110, 120, 232, 234, 301, 302: substrate
130, 150, 230, 250: transparent electrode 140, 240: electrochromic layer
142, 242: electrochromic particles 144, 244: solid electrolyte
200: display device 210: display panel

Claims (6)

With ionic salts;
Polymer matrix formed by polymerization of a first oligomer represented by the following formula (1) and a second oligomer represented by the following formula (2)
Solid electrolyte comprising a.
[Formula 1]

[Formula 2]

(M1+m2=1 in Formula 1, and m3+m4=1 in Formula 2.)
The method of claim 1,
The polymer matrix is represented by the following formula, and x+y=1.

The method of claim 2,
A solid electrolyte where x is equal to or greater than y.
The method of claim 1,
The ionic salt is a lithium salt.
First and second substrates facing each other;
A first transparent electrode on the first substrate;
A second transparent electrode on the second substrate;
An electrochromic particle layer positioned between the first transparent and the second transparent electrode;
A solid electrolyte layer comprising the solid electrolyte of any one of claims 1 to 4 positioned between the second transparent electrode and the electrochromic particle layer
Transmittance variable panel comprising a.
The variable transmittance panel of claim 5;
A display panel positioned on one side of the variable transmittance panel and including a display portion and a transparent portion
Display device comprising a.

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