KR20180120828A - Protective film compound manufacturing method and transparent electrode manufacturing method - Google Patents

Abstract

The present invention relates to a method for producing a protective film composition, and a method for producing a protective film for metal fibers. According to an embodiment of the present invention, the method for producing the protective film composition comprises the following steps: preparing a solvent containing ethanol; adding an alkali metal salt and an ultraviolet resin to the solvent; and dispersing the alkali metal salt and the ultraviolet resin in the solvent. According to the present invention, it is possible to increase durability and lifespan of transparent electrodes.

Description

TECHNICAL FIELD [0001] The present invention relates to a transparent electrode composition,

The present invention relates to a process for producing a protective film composition and a process for producing a transparent electrode.

Almost all materials that are used in various products, electronic devices, electronic components or various industries are exposed to frequent scratching environment, water or heat elements, and are subject to wear, impact, contamination and corrosion due to scratches There is a problem in that a great economic loss occurs due to the chemical change due to the chemical change. Therefore, studies on methods for minimizing the above problems by applying or treating a coating composition having functions such as abrasion resistance, impact resistance, chemical resistance, moisture resistance, salt resistance, corrosion resistance and weather resistance to a surface to be protected have reached a considerable level have.

However, most of these methods require a high-temperature process or a long-time process. Particularly, a material having a form including a resin susceptible to heat, including various low-molecular and high-molecular substances, There is a fear that this is denatured. Therefore, a coating method using ultraviolet curing, which is a process which can be terminated at a lower temperature in a short time, has been studied in recent years, and it has been gradually put to practical use.

Transparent conductive films used for transparent electrodes in the touch panel market of the display industry generally use indium tin oxide (ITO). However, ITO is synthesized by using relatively expensive equipment, and has brittleness characteristic specific to inorganic materials, so that it is limited to use on a plastic substrate. Silver (Ag) is the material with the highest electrical conductivity among the existing metals. The surface of the silver nanoparticles is composed of several crystal planes. Using this difference in reactivity, the isotropic growth can be induced to form a nanowire. These silver nanowires are inexpensive manufacturing cost, have excellent flexibility, exhibit electrical and physical properties similar to those of ITO, and are attracting attention as transparent electrodes to replace ITO in various electronic devices such as displays and solar cells. However, the currently developed silver nanowires are very vulnerable to heat, so they can not be applied to high-temperature processes and various post-treatment processes of electronic devices. When additives are used to improve heat resistance and durability, the electrical and optical characteristics of the material There is a lowering limit.

Korean Patent Publication No. 10-2013-0132025

The present invention provides a method for manufacturing a protective film composition and a method for manufacturing a transparent electrode, which can protect an element to which the silver nanowire electrode is applied from heat and moisture while maintaining electrical characteristics and optical characteristics of the element to which the silver nanowire electrode is applied .

A method for preparing a protective film composition according to an embodiment of the present invention includes: preparing a solvent containing ethanol; Adding an alkali metal salt to the solvent; And dispersing the alkali metal salt in the solvent.

Further, in the step of adding an alkali metal salt to the solvent, an ultraviolet resin may be further added.

Also, the content of the alkali metal salt added to the solvent may be 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.

In addition, the cation of the alkali metal salt may include at least one of cesium (Cs), rubidium (Rb), and potassium (K).

The alkali metal salt may be at least one of an alkali metal carbonate, an alkali metal iodide, an alkali metal chloride or an alkali metal bromate.

The method may further include the step of adding a photoinitiator to the solvent.

The method may further include adding a surfactant to the solvent.

The protective film composition according to another embodiment of the present invention includes an alkali metal; and the cation of the alkali metal salt includes at least one of cesium (Cs), rubidium (Rb), and potassium (K).

The content of the alkali metal salt contained in the protective film composition may be 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.

In addition, the protective film composition may further include an additive including at least one of a photoinitiator, a surfactant, and an ultraviolet resin.

A method of fabricating a transparent electrode according to another embodiment of the present invention includes: depositing a metal nanowire electrode on a transparent flexible substrate; And applying a protective film on the silver nanowire electrode, wherein the protective film comprises: preparing a solvent containing ethanol; Adding an alkali metal salt to the solvent; And dispersing the alkali metal salt in the solvent.

The method for producing a protective film composition according to an embodiment of the present invention can produce a protective film composition having excellent heat resistance by a simple method and the method for manufacturing a transparent electrode according to another embodiment of the present invention is characterized in that the electrical characteristics and optical characteristics The transparent electrode can be protected from heat and moisture while the transparent electrode is applied, thereby improving the lifetime and durability of the transparent electrode.

FIG. 1 shows the steps of a method for producing a protective film composition according to an embodiment of the present invention.
Fig. 2 shows the application of UV to a transparent electrode fabricated according to another embodiment of the present invention.
3 is an XPS graph of the protective film prepared by Example 1 and Comparative Example 1 at 0 to 1400 eV.
4 is an XPS graph of the protective film prepared by Example 1 and Comparative Example 1 around 725 eV.
5A is a photograph of an AFM measurement of silver nanowires deposited on a transparent flexible substrate.
FIG. 5B is a photograph of AFM measurement of the protective film prepared according to Comparative Example 1. FIG.
5C is a photograph of AFM measurement of the protective film prepared according to Example 1. Fig.
6 is a graph showing a thermogravimetric analysis of the protective film prepared in Example 1 and Comparative Example 1. Fig.
7 is a graph showing changes in sheet resistance of a silver nanowire deposited on a protective film prepared by Example 1, Example 2, Example 3, and Comparative Example 1 and silver nanowires deposited on a transparent flexible substrate at 150 ° C / 85% .
8 is a graph showing changes in sheet resistance of a silver nanowire deposited on a protective film prepared by Example 1, Example 4, Example 5, and Comparative Example 1 and silver nanowires deposited on a transparent flexible substrate at 150 ° C / 85% .
FIG. 9 is a graph showing the heat resistance test of the silver nanowires deposited on the protective film and the transparent flexible substrate prepared in Example 1, Example 6, Example 7, Example 8, and Comparative Example 1 under conditions of 150 ° C./85% relative humidity The change of the sheet resistance is shown.
10 shows changes in sheet resistance of the protective film prepared in Example 1 and Comparative Example 2 by a heat resistance test under the conditions of 150 占 폚 / 85% relative humidity.
FIG. 11A is a scanning electron microscope (SEM) image of a silver nanowire deposited on a transparent flexible substrate before and after a heat resistance test at 150 ° C./85% relative humidity.
11B is a scanning electron microscopic photograph of the protective film prepared in Comparative Example 1 before and after the heat resistance test at 150 DEG C / 85% relative humidity.
FIG. 11C is a scanning electron microscopic photograph of the protective film prepared in Example 1 before and after the heat resistance test at 150 ° C / 85% relative humidity. FIG.
12 is a graph showing changes in sheet resistance of a silver nanowire deposited on a protective film prepared by Example 1 and Comparative Example 1 and a transparent flexible substrate according to a heat resistance test at 85 ° C / 85% relative humidity.
13A is a scanning electron microscope (SEM) image of silver nanowires deposited on a transparent flexible substrate before and after a heat resistance test at 85 ° C / 85% relative humidity.
Fig. 13B is a scanning electron microscopic photograph of the protective film prepared before and after the heat resistance test under the 85 占 폚 / 85% relative humidity condition of the protective film prepared in Comparative Example 1. Fig.
13C is a scanning electron microscope photograph before / after the heat resistance test under the 85 占 폚 / 85% relative humidity condition prepared in Example 1. Fig.
14 shows UV-VIS transmittance at 200 to 800 nm of silver nanowires deposited on a protective film, a PES substrate, and a transparent flexible substrate prepared according to Example 1 and Comparative Example 1. FIG.
FIG. 15 shows UV-VIS transmittance at 400 to 800 nm of silver nanowires deposited on a protective film prepared by Example 1 and Comparative Example 1, a PES substrate, and a transparent flexible substrate.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. Therefore, the shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity, and the elements denoted by the same reference numerals in the drawings are the same elements. The same reference numerals are used throughout the drawings to denote like parts and functions. In addition, " including " an element throughout the specification does not exclude other elements unless specifically stated to the contrary.

Method for producing protective film composition

FIG. 1 shows the steps of a method for producing a protective film composition according to an embodiment of the present invention. Referring to FIG. 1, a method for preparing a protective film composition according to an embodiment of the present invention includes: preparing a solvent containing ethanol; Adding an alkali metal salt and an ultraviolet resin to the solvent; And dispersing the alkali metal salt and the ultraviolet resin in the solvent.

In the step of preparing the solvent containing ethanol, the solvent containing ethanol may be ethanol, or may further include a different alcohol solvent in addition to ethanol.

The heterogeneous alcohol solvent may be diacetone alcohol or isopropyl alcohol.

In the step of adding an alkali metal salt to the solvent, an ultraviolet resin may be further added.

The ultraviolet resin may be silica sol or alumina sol, and is not particularly limited thereto.

In the step of dispersing the alkali metal salt in the solvent, it can be dispersed through an agitator for even dispersion of the alkali metal salt, and an appropriate temperature can be applied.

The content of the alkali metal salt added to the solvent may be 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.

If the content of the metal is less than 0.05 wt% with respect to the total mass of the protective film composition, the heat shielding performance of the protective film may be deteriorated. If the content of the metal exceeds 1.0 wt% with respect to the total mass of the protective film composition, the haze may increase and the optical characteristics may be deteriorated.

The cation of the alkali metal salt may include at least one of cesium (Cs), rubidium (Rb), and potassium (K).

The protective film composition prepared by including at least one of cations of cesium (Cs), rubidium (Rb), and potassium (K) in the alkali metal salt can improve the heat resistance and moisture resistance of the protective film produced thereby.

The alkali metal salt may be at least one of an alkali metal carbonate, an alkali metal iodide, an alkali metal chloride or an alkali metal bromide.

The alkali metal carbonate may be at least one of cesium carbonate (Cs ₂ CO ₃ ), rubidium carbonate (Rb ₂ CO ₃ ), or potassium carbonate (K ₂ CO ₃ ). The alkali metal iodide salt may be a cesium iodide salt, a rubidium iodide salt or a potassium iodide salt. The alkali metal chloride flame may be a cesium chloride flame, a rubidium chloride flame or a potassium chloride salt. The alkali metal bromate may be cesium bromide, rubidium bromide or potassium bromide.

And adding a photoinitiator to the solvent.

The photoinitiator may act to initiate a curing reaction in the curing process by ultraviolet light.

The photoinitiator may be selected from the group consisting of benzophenone, Irgacure 184 (1-Hydroxy-cyclohexyl phenyl ketone), Irgacure 1173 (2-Hydroxy-2-methyl- - (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone and Darocure TPO (2,4,6-trimethylbenzoyl) phos- And the like.

And adding a surfactant to the solvent.

The surfactant may be a silicone type surfactant or a fluorine type surfactant. Specifically, the silicone type surfactant may be BYK-077, BYK-085, BYK-300, BYK-301, BYK-302, BYK- -307, BYK-310, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-335, BYK-341v344, BYK-345v346, , BYK-354, BYK-355, BYK-356, BYK-358, BYK-361, BYK-370, BYK-371, BYK- Examples of the fluorine surfactant include F-114, F-177, F-410, F-411, F-450, F-493, F-494, F-443, F- F-482, F-483, F-485, F-485, F-485, F-485, F-485, F- , F-484, F-486, F-487, F-172D, MCF-350SF, TF-1025SF, TF-1117SF, TF- 1026SF, TF- 1128, TF- 1127, TF- -1130, TF-1116SF, TF-1131, TF1132, TF1027SF, TF-1441, TF-1442 and the like.

Protective film composition

The protective film composition according to another embodiment of the present invention includes an alkali metal; and the cation of the alkali metal salt includes at least one of cesium (Cs), rubidium (Rb), and potassium (K).

The protective film composition prepared by including at least one of cations of cesium (Cs), rubidium (Rb), and potassium (K) in the alkali metal salt can improve the heat resistance and moisture resistance of the protective film produced thereby.

The alkali metal salt may be at least one of an alkali metal carbonate, an alkali metal iodide, an alkali metal chloride or an alkali metal bromide.

The alkali metal carbonate may be at least one of cesium carbonate (Cs ₂ CO ₃ ), rubidium carbonate (Rb ₂ CO ₃ ), or potassium carbonate (K ₂ CO ₃ ). The alkali metal iodide salt may be a cesium iodide salt, a rubidium iodide salt or a potassium iodide salt. The alkali metal chloride flame may be a cesium chloride flame, a rubidium chloride flame or a potassium chloride salt. The alkali metal bromate may be cesium bromide, rubidium bromide or potassium bromide.

The content of the alkali metal salt contained in the protective film composition may be 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.

If the content of the alkali metal salt is less than 0.05 wt% with respect to the total mass of the protective film composition, the heat shielding performance of the protective film may be deteriorated. If the content of the metal exceeds 1.0 wt% with respect to the total mass of the protective film composition, the haze may increase and the optical characteristics may be deteriorated.

The protective film composition may further include an additive including at least one of a photoinitiator, a surfactant, and an ultraviolet resin.

The photoinitiator may act to initiate a curing reaction in the curing process by ultraviolet light.

The photoinitiator may be selected from the group consisting of benzophenone, Irgacure 184 (1-Hydroxy-cyclohexyl phenyl ketone), Irgacure 1173 (2-Hydroxy-2-methyl- - (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone and Darocure TPO (2,4,6-trimethylbenzoyl) phos- And the like.

The surfactant may be a silicone type surfactant or a fluorine type surfactant. Specifically, the silicone type surfactant may be BYK-077, BYK-085, BYK-300, BYK-301, BYK-302, BYK- -307, BYK-310, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-335, BYK-341v344, BYK-345v346, , BYK-354, BYK-355, BYK-356, BYK-358, BYK-361, BYK-370, BYK-371, BYK- Examples of the fluorine surfactant include F-114, F-177, F-410, F-411, F-450, F-493, F-494, F-443, F- F-482, F-483, F-485, F-485, F-485, F-485, F-485, F- , F-484, F-486, F-487, F-172D, MCF-350SF, TF-1025SF, TF-1117SF, TF- 1026SF, TF- 1128, TF- 1127, TF- -1130, TF-1116SF, TF-1131, TF1132, TF1027SF, TF-1441, TF-1442 and the like.

The ultraviolet resin may be silica sol or alumina sol, and is not particularly limited thereto.

Method for manufacturing transparent electrode

A method of fabricating a transparent electrode according to another embodiment of the present invention includes: depositing a metal nanowire electrode on a transparent flexible substrate; And applying a protective film on the metal nanowire electrode, wherein the protective film comprises: preparing a solvent containing ethanol; Adding an alkali metal salt to the solvent; And dispersing the alkali metal salt in the solvent.

(PET), polyethylene naphthalate (PEN), polyethylene (PE), polyethersulfone (PES), polycarbonate (PC), and the like. The transparent flexible substrate used in the present invention can be used without any particular limitation, , Polyarylate (PAR), and polyimide (PI), or preferably polyethylene terephthalate (PET).

The metal nanowire may preferably be a silver nanowire.

Silver (Ag) is the most conductive material among metals and has a self resistance value of 80 to 120, which is lower than that of ITO having a thickness of 200 to 400, which is not only advantageous for enlargement but also can be applied to a flexible display. In addition, the silver nanowire is almost colorless and can not distort the display image.

The protective film on the transparent electrode prepared by the above method can be cured by ultraviolet irradiation.

The ultraviolet ray irradiation can be carried out by means of, for example, a high-pressure mercury lamp, an electrodeless lamp, or a xenon lamp. The irradiation dose in the ultraviolet curing system is not particularly limited as long as it is controlled so as to sufficiently cure without compromising the physical properties of the pressure-sensitive adhesive layer. For example, when the illuminance is 50 mW / cm ² to 1,000 mW / cm ² , mJ / cm < ² > to 1,000 mJ / cm < ² >.

The protective film manufactured according to an embodiment of the present invention can be preferably used to form a protective film, a heat resistant film, and the like of an electronic product such as a touch screen, a display, and a solar cell.

In the step of applying the protective film on the metal nanowire electrode, a method of applying the protective film may be, for example, the following method.

For example, a coating film is formed by applying a composition for forming a silica-based coating film on a substrate by a coating method such as spin coating, cast coating or roll coating so as to have a predetermined film thickness. It is then baked on a hot plate. The bake temperature at this time is, for example, about 80 to 300 占 폚. The bake treatment can be performed by a plurality of steps while changing the bake temperature.

In the step of preparing the solvent containing ethanol, the solvent containing ethanol may be ethanol, or may further include a different alcohol solvent in addition to ethanol.

The heterogeneous alcohol solvent may be diacetone alcohol or isopropyl alcohol.

In the step of adding an alkali metal salt to the solvent, an ultraviolet resin may be further added.

The ultraviolet resin may be silica sol or alumina sol, and is not particularly limited thereto.

In the step of dispersing the alkali metal salt in the solvent, it can be dispersed through an agitator for even dispersion of the alkali metal salt, and an appropriate temperature can be applied.

The content of the alkali metal salt added to the solvent may be 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.

If the content of the alkali metal salt is less than 0.05 wt% with respect to the total mass of the protective film composition, the heat shielding performance of the protective film may be deteriorated. If the content of the metal exceeds 1.0 wt% with respect to the total mass of the protective film composition, the haze may increase and the optical characteristics may be deteriorated.

The cation of the alkali metal salt may include at least one of cesium (Cs), rubidium (Rb), and potassium (K).

The protective film composition prepared by including at least one of cations of cesium (Cs), rubidium (Rb), and potassium (K) in the alkali metal salt can improve the heat resistance and moisture resistance of the protective film produced thereby.

The alkali metal salt may be at least one of an alkali metal carbonate, an alkali metal iodide, an alkali metal chloride or an alkali metal bromide.

The alkali metal salt may be at least one of an alkali metal carbonate, an alkali metal iodide, an alkali metal chloride or an alkali metal bromide.

The alkali metal carbonate may be at least one of cesium carbonate (Cs ₂ CO ₃ ), rubidium carbonate (Rb ₂ CO ₃ ), or potassium carbonate (K ₂ CO ₃ ). The alkali metal iodide salt may be a cesium iodide salt, a rubidium iodide salt or a potassium iodide salt. The alkali metal chloride flame may be a cesium chloride flame, a rubidium chloride flame or a potassium chloride salt. The alkali metal bromate may be cesium bromide, rubidium bromide or potassium bromide.

And adding a photoinitiator to the solvent.

The photoinitiator may act to initiate a curing reaction in the curing process by ultraviolet light.

The photoinitiator may be selected from the group consisting of benzophenone, Irgacure 184 (1-Hydroxy-cyclohexyl phenyl ketone), Irgacure 1173 (2-Hydroxy-2-methyl- - (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone and Darocure TPO (2,4,6-trimethylbenzoyl) phos- And the like.

And adding a surfactant to the solvent.

The surfactant may be a silicone type surfactant or a fluorine type surfactant. Specifically, the silicone type surfactant may be BYK-077, BYK-085, BYK-300, BYK-301, BYK-302, BYK- -307, BYK-310, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-335, BYK-341v344, BYK-345v346, , BYK-354, BYK-355, BYK-356, BYK-358, BYK-361, BYK-370, BYK-371, BYK- Examples of the fluorine surfactant include F-114, F-177, F-410, F-411, F-450, F-493, F-494, F-443, F- F-482, F-483, F-485, F-485, F-485, F-485, F-485, F- , F-484, F-486, F-487, F-172D, MCF-350SF, TF-1025SF, TF-1117SF, TF- 1026SF, TF- 1128, TF- 1127, TF- -1130, TF-1116SF, TF-1131, TF1132, TF1027SF, TF-1441, TF-1442 and the like.

Example 1

Preparation of protective film composition

0.05 g of silica sol (RANCO) as an ultraviolet resin and 0.05 g of Cs ₂ CO ₃ (Sigma Aldrich) as an alkali metal salt were mixed with 49.2 g of ethanol (99.5%, Dongwha Fine Chem) and 4-hydroxy- (1-Hydroxycyclohexyl phenyl ketone 99%, Sigma Aldrich), 0.1 g of surface active agent BYK-310 (BYK Additives & Instruments) as a further additive, , And 0.1 g of TPO (97% of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, Sigma Aldrich) were added to the solvent, and the mixture was stirred at room temperature for about 60 minutes through a stirrer to prepare a Cs- Respectively.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Example 2

Preparation of protective film composition

0.05 g of silica sol as an ultraviolet resin and 0.05 g of Rb ₂ CO ₃ as an alkali metal salt were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol and then 0.1 g of surface active agent BYK-310 and 0.3 g of photoinitiator I-184 And 0.1 g of TPO were put into a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare an Rb-containing protective film composition.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above-described protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and heat treatment was performed at a temperature of 130 캜 for about 1 minute to prepare a protective film containing Rb. To prepare two samples.

Example 3

Preparation of protective film composition

0.05 g of silica sol as an ultraviolet resin and 0.05 g of K ₂ CO ₃ as an alkali metal salt were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol. Then, 0.1 g of surface active agent BYK-310 and 0.3 g of photoinitiator I-184 And 0.1 g of TPO were put into a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare a K-containing protective film composition.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above-described protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute, and a protective film was coated thereon. Heat treatment was performed at a temperature of 130 캜 for about 1 minute to prepare a K-containing protective film. To prepare two samples.

Example 4

Preparation of protective film composition

0.05 g of silica sol as an ultraviolet resin and 0.1 g of Cs ₂ CO ₃ as an alkali metal salt were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol. Then, 0.1 g of surface active agent BYK-310 and 0.3 g of photoinitiator I-184 And 0.1 g of TPO were put into a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare a Cs-containing protective film composition.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Example 5

Preparation of protective film composition

0.05 g of silica sol and 1 g of Cs ₂ CO ₃ as an ultraviolet resin were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol. Then, 0.1 g of surface active agent BYK-310, 0.3 g of photoinitiator I-184 And 0.1 g of TPO were put in a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare a protective film composition containing Cs.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Example 6

Preparation of protective film composition

0.05 g of silica sol as an ultraviolet resin and 0.05 g of CsCl as an alkali metal salt were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol. Then, 0.1 g of surface active agent BYK-310, 0.3 g of photoinitiator I-184 and 0.1 g of TPO 0.1 g were put in a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare a protective film composition containing Cs.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Example 7

Preparation of protective film composition

0.05 g of silica sol as an ultraviolet resin and 0.05 g of CsBr as an alkali metal salt were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol. Then, 0.1 g of surface active agent BYK-310, 0.3 g of photoinitiator I-184 and 0.1 g of TPO 0.1 g were put in a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare a protective film composition containing Cs.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Example 8

Preparation of protective film composition

0.05 g of silica sol as an ultraviolet resin and 0.05 g of CsI as an alkali metal salt were added to a mixed solvent of 49.2 g of ethanol and 49.3 g of diacetone alcohol. Then, 0.1 g of surface active agent BYK-310, 0.3 g of photoinitiator I-184 and 0.1 g of TPO 0.1 g were put in a solvent together and stirred for about 60 minutes at room temperature through a stirrer to prepare a protective film composition containing Cs.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Comparative Example 1

Preparation of protective film composition

Example 1 was repeated except that Cs ₂ CO ₃ was not added as an alkali metal salt in Example 1 but 49.2 g of isopropyl alcohol and 49.3 g of diacetone alcohol were used instead of the mixture of ethanol and diacetone alcohol as a solvent. A protective film composition was prepared in the same manner.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The protective layer composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective layer coating. The protective layer was heat treated at a temperature of 130 캜 for about 1 minute to form a protective layer. Were prepared.

Comparative Example 2

Preparation of protective film composition

In Example 1, a protective film composition was prepared in the same manner as in Example 1, except that 49.2 g of isopropyl alcohol and 49.3 g of diacetone alcohol were used instead of the mixture of ethanol and diacetone alcohol as a solvent.

Transparent electrode manufacturing

A dispersion containing silver nanowires was coated on a PES substrate at 3000 rpm for about 1 minute using a spin coating apparatus and then subjected to heat treatment at a temperature of 130 캜 for about 1 minute to form silver nanowire electrodes. The above protective film composition was spin-coated on the silver nanowire electrode at 1000 rpm for about 1 minute to form a protective film coating, and the protective film was subjected to heat treatment at a temperature of 130 ° C for about 1 minute to prepare a Cs-containing protective film. To prepare two samples.

Experimental Example - XPS Measurement

In order to confirm the presence of Cs in the protective film containing Cs prepared according to Example 1, an XPS analysis was carried out, which is shown in FIG. 3 and FIG.

Referring to FIGS. 3 and 4, Cs 3d3 and 3d5 peaks which were not observed in Comparative Example 1 were confirmed, and it was confirmed that Cs was present in a protective film containing Cs.

Experimental Example - AFM analysis

Surface photographs of silver nanowires deposited on the protective film and the transparent flexible substrate prepared in Example 1 and Comparative Example 1 were taken using an AFM apparatus, which are shown in FIGS. 5A, 5B, 5C and Table 1. FIG.

5A, 5B, and 5C, it can be seen that the AFM results of the silver nanowires deposited on the transparent flexible substrate show a larger surface roughness distribution than the protective film prepared by Example 1 and Comparative Example 1 .

Also in the numerical values of the AFM measurement results, the average roughness (R _a ) of the protective film according to Example 1 was 2.902 nm, the average roughness (R _a ) of the protective film according to Comparative Example 1 was 4.110 nm, The average roughness (R _a ) of the silver nanowires was measured to be 6.933 nm. As a result of the AFM measurement, it can be seen that the average roughness of the protective film according to the embodiment of the present invention is improved.

Min (nm) Max (nm) Mid (nm) Mean (nm) Ra (nm) Ag NW -22.123 51.069 14.493 0.771 6.933 Comparative Example 1 -19.559 61.372 20.906 0.238 4.110 Example 1 -16.090 58.973 21.441 0.204 2.902

Experimental Example - Thermogravimetric analysis

The thermogravimetric analysis of the protective film prepared according to Example 1 and Comparative Example 1 was carried out in order to evaluate the thermal decomposition tendency according to the temperature rise of the prepared protective film.

Referring to FIG. 6, the 5% weight reduction temperature (T _d ) of the protective film of Example 1 was 173 ° C and the 5% weight reduction temperature (T _d ) of the protective film of Comparative Example 1 was measured at 104 ° C. It can be seen from the above that the protective film on the transparent electrode manufactured according to the embodiment of the present invention is significantly improved in heat resistance as compared with the protective film containing no alkali metal or Cs.

Experimental Example - Protective film heat resistance / moisture resistance test

150 ℃ / 85% relative humidity Protection film heat resistance / moisture resistance test

In order to measure the heat resistance of the protective film prepared according to each example and each comparative example, silver nanowire electrodes deposited on the protective film and the PES substrate prepared according to Examples 1 to 8 and Comparative Examples 1 and 2 were prepared The sheet resistance was measured by the same method while measuring the initial sheet resistance using a non-contact sheet resistance measuring device, and then left at 150 캜 for 120 hours. The sheet resistance was measured in FIGS. 7, 8, 9 and 10.

7, it was confirmed that the heat resistance of the protective film comprising Cs, Rb and K prepared in Examples 1 to 3 was improved as compared with the protective film prepared in Comparative Example 1 containing no alkali metal In particular, the increased heat resistance can be confirmed by adding Cs and Rb to the conventional protective film.

8, the protective film containing Cs prepared according to Example 1, Example 4 and Example 5 had no particular heat resistance tendency depending on the change in the weight part of cesium carbonate added at the time of manufacturing the protective film composition, It can be confirmed that the protective film comprising Cs prepared by Example 1, Example 4 and Example 5 greatly improved in heat resistance as compared with the protective film containing no Cs prepared by Comparative Example 1. [

9, it was confirmed that the protective film containing Cs prepared according to Example 1 and Examples 6 to 8 showed some change in the heat resistance characteristics of the protective film according to the change of the carbonic acid compound added at the time of production of the protective film composition Respectively. When cesium chloride, cesium iodide, cesium bromide and cesium carbonate are added to the protective film in various Cs compounds, it is found that the heat resistance over time is superior in order of cesium chloride, cesium iodide, cesium bromide and cesium carbonate.

10, the protective film containing Cs prepared according to Example 1 and Comparative Example 2 was prepared by adding the same amount of alkali metal salt at the time of production of the protective film, but under the condition that the solvent was different, As a result of time exposure, the tendency of changes in sheet resistance was observed to be almost the same. However, in the section over 72 hours, the sheet resistance of the protective film prepared by Comparative Example 2 was greatly increased. As a result, it can be seen that the solvent containing ethanol greatly affects the heat resistance of the protective film produced by the step of preparing the composition of the protective film.

In order to confirm the surface change by the heat resistance / moisture resistance test, silver nanowire electrodes deposited on the PES substrate of Example 1 and Comparative Example 1 were left at 150 DEG C and their surfaces were observed with a scanning electron microscope. 11a, 11b and 11c.

Referring to FIGS. 11A, 11B, and 11C, the silver nanowire electrodes deposited on the Comparative Example 1 and the PES substrate were subjected to a heat resistance test (FIGS. 11A and 11B) And the protective film prepared in Example 1 (FIG. 11C, bottom view) was observed to have a good appearance with almost no decomposition or deterioration of the silver nanowire electrode. It can be seen from the results that the protective film prepared according to the embodiment of the present invention is greatly improved in the protective characteristics as compared with the protective film prepared according to the comparative example 1 under the heat / moisture resistance test conditions of 150 ° C / 85%.

85 ℃ / 85% relative humidity Protection film heat resistance / moisture resistance test

The protective film prepared according to Example 1 and Comparative Example 1 and silver nanowires deposited on the PES substrate were prepared and the initial sheet resistance was measured using a non-contact type sheet resistance measuring device. The sheet resistance was measured in the same manner while the sheet resistance was maintained for 85 to 55 days This is shown in Fig.

Referring to FIG. 12, it can be seen that the silver nanowire electrode including the protective film, which differs from the embodiment of the present invention, has improved heat resistance as compared with the protective film of Comparative Example 1.

In order to confirm the surface change by the heat resistance and moisture resistance test, the silver nanowire electrode deposited on the PES substrate of Example 1, Comparative Example 1 and the PES substrate was left for 85 to 55 days, and the surface was observed with a scanning electron microscope 13a, 13b and 13c.

13A, 13B, and 13C, the silver nanowire electrode deposited on the PES substrate is subjected to a heat resistance and humidity resistance test (as shown in FIGS. 13A, 13B, and 13C In the drawing, the length of the nanowire is shortened and the disassembled state can be observed.

Experimental Example - Optical Characterization

Measurement of UV-VIS spectra

A protective film prepared according to Example 1 and Comparative Example 1, a PES substrate, and a silver nanowire electrode deposited on the PES substrate were prepared and measured for transmittance at a wavelength ranging from 200 nm to 800 nm using a UV-VIS apparatus. 14, 15 and Table 2, Table 3 and Table 4.

Referring to FIG. 14 and FIG. 15, the protective film prepared according to Example 1 exhibited a minimum transmittance reduction over a wavelength range of 200 nm to 800 nm, and a higher transmittance than a PES substrate at a wavelength of 500 nm or more. Accordingly, it is judged that the protective film according to the embodiment of the present invention does not greatly affect the lowering of the transmittance or the optical characteristics. The following Tables 2, 3 and 4 show the values of the transmittance measured at a wavelength of 550 nm.

Haze measurement

Haze values were measured twice for each sample of silver nanowire electrodes deposited on a PES substrate in Examples 1 to 8 and Comparative Example 1 using a haze meter, Respectively.

Sample T.T (%) Haze Surface resistance
Ag NW

One
87.38 0.75 78 87.59 0.72 77 2
87.33 0.79 69 87.37 0.72 68
Comparative Example 1

One
90.02 0.77 69 90.12 0.74 68 2
89.95 0.72 70 90.12 0.77 70
Example 1

One
90.05 0.78 69 90.20 0.79 68 2
90.10 0.79 76 90.12 0.78 74
Example 2

One
90.12 0.75 72 90.10 0.73 68 2
90.13 0.82 74 90.16 0.83 73
Example 3

One
90.16 0.82 71 90.04 0.77 69 2
90.19 0.79 73 90.03 0.76 69

Referring to Table 2, the transmittance of the protective film prepared by Example 1, Example 2, and Example 3 was almost the same as that of silver nanowire electrodes deposited on the protective film or PES substrate prepared by Comparative Example 1 And no decrease in haze value was observed through the addition of an alkali metal salt containing at least one of Cs, Rb or K. [ The sheet resistance of the protective film prepared by Examples 1, 2 and 3 was also observed at an average of about 70? /?, Which is a numerical value of the silver nanowire electrode deposited on the protective film or the PES substrate prepared by Comparative Example 1 Is a value that does not make a big difference.

Sample T.T (%) Haze Surface resistance
Ag NW

One
87.29 0.83 66 87.39 0.79 64 2
87.43 0.77 70 87.40 0.79 68
Comparative Example 1

One
89.90 0.77 66 90.09 0.84 65 2
90.05 0.81 65 90.08 0.82 64
Example 1

One
89.95 0.88 61 89.93 0.85 61 2
89.81 0.83 62 89.85 0.86 61
Example 4

One
89.79 0.82 64 89.81 0.79 62 2
89.87 0.83 64 90.05 0.87 63
Example 5

One
89.58 5.12 63 89.60 5.09 63 2
89.81 5.07 65 89.49 4.90 64

Referring to Table 3, the transmittance of the protective film prepared according to Example 1, Example 4, and Example 5 was almost the same as that of silver nanowire electrodes deposited on the protective film or PES substrate prepared by Comparative Example 1 Respectively. The haze value of the protective film prepared according to Example 4 was not much different from the protective film prepared according to Example 1 and Comparative Example 1 or the silver nanowire electrode deposited on the PES substrate. However, the haze value of the protective film prepared in Example 5 averaged 5.02, which was greatly increased as compared with the values of the silver nanowire electrodes deposited on the protective film or ES substrate prepared in Example 1 and Comparative Example 1. The sheet resistances of the protective films prepared according to Examples 1, 4 and 5 were measured at an average of 61.25? / ?, 63.25? / ?, and 63.75? /?, Respectively, It is a value that does not greatly differ from the value of the silver nanowire electrode deposited on the substrate.

Sample T.T (%) Haze Surface resistance
Ag NW

One
87.38 0.75 78 87.59 0.72 77 2
87.33 0.79 69 87.37 0.82 68
Example 1

One
90.05 0.78 69 90.20 0.79 68 2
90.10 0.79 76 90.12 0.78 74
Example 6

One
98.87 1.91 72 90.06 1.91 69 2
89.91 2.05 75 89.97 2.06 73
Example 7

One
90.00 1.13 73 89.90 1.10 75 2
90.03 1.19 71 90.13 1.21 75
Example 8

One
90.00 0.81 84 89.89 0.76 89 2
89.78 0.86 84 89.79 0.80 90

Referring to Table 4, the transmittance of the protective film prepared by Example 1, Example 6, Example 7, and Example 8 is compared with the value of the silver nanowire electrode deposited on the protective film or the PES substrate prepared in Comparative Example 1 Respectively. The haze value of the protective film prepared according to Example 8 was not much different from the protective film prepared according to Example 1 and Comparative Example 1 or the silver nanowire electrode deposited on the PES substrate. However, the haze values of the protective films prepared by Example 6 and Example 7 were measured to be 2.00 and 1.16, respectively, and the values of silver nanowire electrodes deposited on the protective film and / or PES substrate prepared by Example 1 and Comparative Example 1 And the value increased greatly. The sheet resistances of the protective films prepared according to Example 1, Example 6, Example 7 and Example 8 were measured at an average of 71.75? / ?, 72.25? / ?, 73.5? / And 86.75? /? The values of the silver nanowire electrodes deposited on the protective film or the PES substrate prepared in Comparative Example 1 are not significantly different from those of the silver nanowire electrode except for the sheet resistance of the protective film according to Example 8. [

The present invention is not limited to the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

Claims (12)

Preparing a solvent comprising ethanol;
Adding an alkali metal salt to the solvent; And
And dispersing the alkali metal salt in the solvent.
The method according to claim 1,
Wherein the content of the alkali metal salt added to the solvent is 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.
The method according to claim 1,
Wherein the cation of the alkali metal salt comprises at least one of cesium (Cs), rubidium (Rb), and potassium (K).
The method according to claim 1,
Wherein the alkali metal salt is at least one of an alkali metal carbonate, an alkali metal iodide, an alkali metal chloride or an alkali metal bromate.
5. The method of claim 4,
Wherein the alkali metal carbonate comprises at least one of cesium carbonate (Cs ₂ CO ₃ ), rubidium carbonate (Rb ₂ CO ₃ ) or potassium carbonate (K ₂ CO ₃ ).
The method according to claim 1,
And adding a photoinitiator to the solvent.
The method according to claim 1,
And adding a surfactant to the solvent.
The method according to claim 1,
And adding ultraviolet resin to the solvent.
Wherein the cation of the alkali metal salt comprises at least one of cesium (Cs), rubidium (Rb), and potassium (K).
10. The method of claim 9,
Wherein the content of the alkali metal salt contained in the protective film composition is 0.05 to 1.0 wt% with respect to the total mass of the protective film composition.
10. The method of claim 9,
Wherein the protective film composition further comprises an additive comprising at least one of a photoinitiator, a surfactant, and an ultraviolet resin.
Depositing a metal nanowire electrode on a transparent flexible substrate; And
And applying a protective film on the silver nanowire electrode,
Wherein the protective film comprises: preparing a solvent containing ethanol; Adding an alkali metal salt to the solvent; And dispersing the alkali metal salt in the solvent.

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