KR101976760B1 - Transparent Conducting Film based on Nanowire and a Method for Preparing Thereof) - Google Patents

Abstract

The present invention relates to a nanowire-based transparent conductive film and a method of manufacturing the same. More particularly, the present invention relates to a nanowire-based transparent conductive film and a method of manufacturing the same. The present invention relates to a transparent conductive film in which environmental stability is ensured by a silicone-based organic-inorganic hybrid polymer binder film, and a method for producing the transparent conductive film.

Description

TECHNICAL FIELD [0001] The present invention relates to a nanowire-based transparent conductive film and a method of manufacturing the nanowire-based transparent conductive film.

The present invention relates to a nanowire-based transparent conductive film and a manufacturing method thereof, and more particularly, to an electroconductive film including a metal nanowire and a conductive polymer; And a silicon-based organic-inorganic hybrid polymer binder film formed on the electroconductive film, and to a method of manufacturing the transparent conductive film.

Transparent conductive thin films are widely used for devices that simultaneously require both light transmission and conductivity, such as touch screen panels (TSP), image sensors, solar cells, and various displays (PDP, LCD, flexible) It is widely used material.

Indium tin oxide (ITO) has been extensively studied as a transparent electrode for a display. However, in order to manufacture a thin film of ITO, a vacuum process is basically required and an expensive process ratio is required. In addition, Is expected to be depleted by rare metals, and the price of raw materials itself is high. Further, when the flexible display device is bent or folded, the lifetime of the display device is shortened due to the breakage of the thin film.

In order to replace ITO, technologies using carbon nanotubes, graphenes, metal nanowires, and metal mesh grids as conductive materials for transparent conductive films are being developed. Transparent conductive films for the replacement of ITO should ensure electrical conductivity, optical properties and environmental stability corresponding to ITO films. Among the conductive materials for replacing the ITO, metal nanowires are attracting attention as materials capable of realizing low resistance, high transparency and flexibility.

When a metal having excellent electrical conductivity has a one-dimensional structure of nanowire shape, an electrically conductive film can be produced by forming a film and forming an electrical network of these. The application to nanowires using metals with excellent electrical conductivity, such as copper, may have an electrically favorable result. In addition, when the film is made into a film having excellent nanowire dispersibility, it is possible to obtain a transmittance of 85% or more in a visible light region because the diameter is several tens of nm. Therefore, a transparent conductive film using metal nanowires, particularly silver or copper nanowires as a conductive material, is a nano material capable of realizing low resistance and high transparency.

For example, Korean Patent Publication No. 2011-0128584 proposes a transparent conductor comprising a substrate, and a transparent conductive coating film provided on either side of the substrate, the transparent conductive coating film including silver nanowires and a binder resin.

However, when such a metal nanowire is made into a film, there is a problem that a portion where a nanowire exists and a portion where a nanowire does not exist exist.

KR 2011-0128584 A

The present invention relates to a method for producing a nanowire-based transparent conductive film, in which a conductive polymer forms an electrically conductive film together with a nanowire to realize a uniform surface resistance and forms a silicon-based organic-inorganic hybrid polymer binder film on the electrically conductive film, And a method for producing the transparent conductive film.

In order to achieve the above object, the present invention provides a substrate comprising: a substrate; An electrically conductive film including a metal nanowire formed on one surface of the substrate and a conductive polymer; And a silicon-based organic-inorganic hybrid polymer binder film formed on the electroconductive film.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming an electroconductive film including a metal nanowire and a conductive polymer on one surface of a substrate; And applying a silicone-based organic-inorganic hybrid polymer solution on the electroconductive film to form a silicone-based organic-inorganic hybrid polymer binder film.

According to the present invention, in the production of the nanowire-based transparent conductive film, the conductive polymer forms an electrically conductive film together with the nanowire to realize uniform surface resistance, and the silicon-based organic-inorganic hybrid polymer binder film is formed on the electroconductive film, A transparent conductive film having stability and a method of manufacturing the same can be provided.

Hereinafter, the present invention will be described in detail.

The present invention relates to a nanowire-based transparent conductive film and a method of manufacturing the same.

More specifically, the invention relates to a substrate; An electrically conductive film including a metal nanowire formed on one surface of the substrate and a conductive polymer; And a silicon-based organic-inorganic hybrid polymer binder film formed on the electroconductive film.

The substrate may include one or more polymeric substrates selected from the group consisting of polyimide, polyethersulfone, polyetheretherketone, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyacrylate, and polyurethane .

The metal nanowires are preferably silver nanowires, copper nanowires, or a mixture thereof.

The metal nanowires preferably have an average diameter range of 10 to 40 nm and an average length range of 10 to 50 μm.

When the metal nanowire is in the above range, the transparent conductive film can obtain properties such as appropriate optical properties and surface resistance.

When the metal nanowires are formed into a film, portions where the nanowires exist and regions where the nanowires are not present are generated. Such an empty portion is a problem that prevents the nanowire film from having a uniform sheet resistance over the entire surface. In particular, non-uniform dispersion of filmed nanowires can make the sheet resistance more uneven. To solve this problem, the present inventors introduced a coating of a conductive polymer material to form a film on a two-dimensional plane, thereby forming an electrically conductive film containing the nanowire and the conductive polymer.

The conductive polymer used in the present invention is preferably one or a mixture of two or more selected from the group consisting of polyacetylene, polypyrrole, polyaniline, polythiophene and derivatives thereof, more preferably polythiophene conductive polymer .

The polythiophene-based conductive polymer is preferably poly-3,4-ethylenedioxythiophene / polystyrene sulfonate (PEDOT / PSS). PSS is a dopant of PEDOT, which is used for increasing the solubility of PEDOT, and it is preferable that the PSS ratio to PEDOT is 1 to 2 times.

In order to improve the environmental stability, particularly the weather resistance, of the electroconductive film comprising the metal nanowire and the conductive polymer, the inventors of the present invention have found that by introducing the silicon-based organic-inorganic hybrid polymer on the electroconductive film, the electroconductive film containing the metal nanowire and the conductive polymer And a silicon-based organic-inorganic hybrid polymer binder film formed on the electroconductive film.

That is, the transparent conductive film of the present invention includes a silicon-based organic-inorganic hybrid polymer film, which can improve surface hardness, impart excellent weather resistance, solvent resistance, and chemical resistance, Functionality can be given.

In general, a silicone-based polymer has characteristics of low surface tension. The surface tension of polar solvents such as water is relatively large, which makes a great difference in terms of surface tension with respect to the silicone polymer. Due to such difference, the silicone polymer mainly exhibits strong hydrophobicity and can exhibit a strong resistance to weathering in the external environment due to such properties.

The silicon-based organic-inorganic hybrid polymer is preferably at least one selected from the group consisting of polycarbosilane, polysilane, polysiloxane, polysilazane, and derivatives thereof. The silicon-based organic-inorganic hybrid polymer selected from the group consisting of polycarbosilane, polysilane, polysiloxane, polysilazane, and derivatives thereof has an advantage in that the function described above can be specified according to the choice of substituent.

The transparent conductive film has a surface resistance of 500 Ω / □ or less, a transparency of 85% or more, and a haze of 5% or less.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming an electroconductive film including a metal nanowire and a conductive polymer on one surface of a substrate; And applying a silicone-based organic-inorganic hybrid polymer solution on the electroconductive film to form a silicone-based organic-inorganic hybrid polymer binder film.

The step of forming an electrically conductive film including a metal nanowire and a conductive polymer on one side of the substrate may include applying a solution containing the metal nanowire to a substrate and then applying a solution containing the conductive polymer, To form an electrically conductive film.

The substrate may include one or more polymeric substrates selected from the group consisting of polyimide, polyethersulfone, polyetheretherketone, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyacrylate, and polyurethane .

The metal nanowires are preferably silver nanowires, copper nanowires, or a mixture thereof. The metal nanowires preferably have an average diameter range of 10 to 40 nm and an average length range of 10 to 50 μm. When the metal nanowire is in the above range, the transparent conductive film can obtain properties such as appropriate optical properties, surface resistance, and weather resistance.

The solution containing the metal nanowires is a metal nanowire solution in which metal nanowires are dispersed in a solvent such as water or alcohol in a solid content of 0.1 to 1.5 wt%. Less than 0.1 wt.% Of the solution may not have a sufficient network formation after coating and may cause no surface resistance, and a solution of more than 1.5 wt.% May cause agglomeration of the metal nanowires in the solution, It may affect optical properties.

The process of coating the metal nanowire solution on the substrate may be selected from spray coating, bar coating, dip coating, spin coating, slit die coating, curtain coating, gravure coating, reverse gravure coating, roll coating and impregnation. A film in which the metal nanowires are coated on the substrate by the metal nanowire coating can be obtained.

In the method of manufacturing a transparent conductive film of the present invention, a solution containing a metal nanowire is coated on one surface of a substrate, and then a solution containing a conductive polymer is applied to form an electroconductive film.

In the solution containing the conductive polymer, the solvent is alcohol and the content of the conductive polymer is about 0.5 to 5% by weight in view of stability of the coating liquid, coating property and physical properties after forming the conductive polymer film.

If the content of the conductive polymer in the conductive polymer solution is less than 0.5% by weight, it is difficult to form a uniform film on the metal nanowire after the film is formed, and thus it may be difficult to ensure uniform physical properties and reliability. When the content is more than 5% by weight, aggregation may occur in the solution, and there may be a problem that a uniform coating film can not be obtained at the time of coating due to such a lump.

The process of coating the conductive polymer solution on the metal nanowire film may be selected from spray coating, bar coating, dip coating, spin coating, slit die coating, curtain coating, gravure coating, reverse gravure coating, roll coating and impregnation .

The conductive polymer is preferably a mixture of at least one member selected from the group consisting of polyacetylene, polypyrrole, polyaniline, polythiophene and derivatives thereof, more preferably a polythiophene conductive polymer. The polythiophene-based conductive polymer is preferably poly-3,4-ethylenedioxythiophene / polystyrene sulfonate (PEDOT / PSS).

The method for manufacturing a transparent conductive film of the present invention includes a step of applying a silicone-based organic-inorganic hybrid polymer solution on the electroconductive film to form a polymeric binder film.

The silicon-based organic-inorganic hybrid polymer is preferably one selected from the group consisting of polycarbosilane, polysilane, polysiloxane, polysilazane, and derivatives thereof.

The silicone-based organic-inorganic hybrid polymer solution may be a solution in which the solvent is an organic solvent and the silicon-based organic-inorganic hybrid polymer is dissolved in an amount of 0.01 to 10 wt%. The organic solvent is preferably one selected from the group consisting of methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, tetrahydrofuran, hexane, propylene glycol monomethyl ether acetic acid, propylene glycol monomotel ether and the like. It is easy to form a film when a polymer solution within the above concentration range is coated. If the concentration is out of the above range, the formed film may have characteristics such as surface resistance characteristics and adhesion properties.

In one preferred embodiment of the present invention, a film is formed by impregnating a silicon-based organic-inorganic hybrid polymer solution with a film on which an electroconductive film is formed, or by coating the substrate with a silicon-based organic-inorganic hybrid polymer solution, followed by drying and curing, A hybrid polymer membrane can be formed.

The drying may be performed by drying the silicon-based organic-inorganic hybrid polymer film formed on the substrate at 80 ° C to 400 ° C for 2 minutes or more. If the temperature and the time range are out of the range, the residual solvent in the non-dried film acts as an obstacle in the subsequent curing step, which may hinder the formation of a uniform silicon-based organic-inorganic hybrid polymer film, have.

The curing step may be performed at a temperature of 80 ° C to 150 ° C and a humidity of 80RH% to 95RH%, or by exposure to ultraviolet light of 100mJ to 1000mJ. The silicon-based organic-inorganic hybrid polymer may be cured to form a silicon-based organic-inorganic hybrid polymer film even outside the temperature and humidity ranges. However, considering the curing rate and the density of the formed film in particular, . The curing using ultraviolet rays can adjust the exposure intensity by adjusting the exposure time and is not limited to the above conditions.

According to the transparent conductive film production method of the present invention, a transparent conductive film having a surface resistance of 500? / ?, a transparency of 85% or more, and a haze of 5% or less can be produced.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to the following examples. However, the present invention is not limited to these examples.

Example  One

A solution in which 0.1 wt% of nanowires were dispersed in water was stitched for 30 minutes. The PET substrate was prepared, and the dispersed silver nanowire solution was applied and then bar coated. Coated silver substrate with a nanowire was dried in an oven at 80 DEG C for 2 minutes to obtain a silver nanowire film.

A methanol solution-based conductive polymer solution, that is, a 0.3 wt% solution of PEDOT (Poly (3,4-ethylenedioxythiophene)) was prepared, and then applied onto the silver nanowire film. The substrate coated with the conductive polymer was dried at 80 ° C for 2 minutes and then cured at 120 ° C for 10 minutes to prepare an electrically conductive film-coated film containing the silver nanowire and the conductive polymer.

Then, 1.0 wt% of polysilazane (polymeric binder) methyl ethyl ketone solution was bar-coated on the conductive material film. Thereafter, the substrate was dried at 120 DEG C and then treated at 80 DEG C and 95% RH for 3 hours to form a polymer film. An electroconductive film including a metal nanowire and a conductive polymer on a substrate, and a silicone- A transparent conductive film containing a polymeric binder film was obtained.

Example  2

A conductive film was prepared in the same manner as in Example 1 except that a solution in which 0.3 wt% of silver nanowires were dispersed in water was used.

Example  3

A conductive film was prepared in the same manner as in Example 1, except that a solution in which 0.5 wt% of silver nanowire was dispersed in water was used.

Example  4

A conductive film was prepared in the same manner as in Example 1 except that a solution in which 1.0 wt% of silver nanowires were dispersed in water was used.

Comparative Example  One

A solution in which nanowires were dispersed in water at 0.3 wt% was stitched for 30 minutes. After the PET substrate was prepared, the dispersed silver nanowire solution was applied and then bar-coated. Coated silver substrate with a nanowire was dried in an oven at 80 DEG C for 2 minutes to obtain a silver nanowire film.

A methanol solution-based conductive polymer solution, that is, a 0.3 wt% solution of PEDOT (poly (3,4-ethylenedioxythiophene)) was prepared and then coated on the above prepared nanowire film and then bar coated. The substrate coated with the conductive polymer was dried at 80 ° C for 2 minutes and then cured at 120 ° C for 10 minutes to prepare an electrically conductive film-coated film comprising the metal nanowire and the conductive polymer.

Comparative Example  2

A solution in which nanowires were dispersed in water at 0.3 wt% was stitched for 30 minutes. After the PET substrate was prepared, the dispersed silver nanowire solution was applied and then bar-coated. Coated silver substrate with a nanowire was dried in an oven at 80 DEG C for 2 minutes to obtain a silver nanowire film.

Then, 1.0 wt% of polysilazane (polymeric binder) methyl ethyl ketone solution was bar coated on the silver nanowire film. Thereafter, the substrate was dried at 120 DEG C and then treated at 80 DEG C and 95% RH for 3 hours to form a polymer film, and an electrically conductive film in which metal nanowires were present singly on the substrate and a silicon-based organic-inorganic hybrid polymer formed on the electroconductive film Thereby obtaining a transparent conductive film containing a binder film.

≪ Evaluation of physical properties &

The following properties of the transparent conductive films obtained in Examples 1 to 4 and Comparative Examples 1 and 2 were evaluated. The results are shown in Table 1 below.

(1) Evaluation of optical characteristics

The visible light transmittance and haze of the transparent conductive films obtained in Examples 1 to 4 and Comparative Examples 1 to 2 were measured using a UV spectrometer (Nippon Denshoko, NDH2000) and are shown in Table 1 below.

(2) Evaluation of surface resistance

(Hiresta-UP MCT-HT450 (Mitsuibishi Chemical Corporation) (measurement range: 10 x 10 ⁵ to 10 x 10 ¹⁵ ) and a low-resistance meter (trade name, manufactured by Mitsubishi Chemical Corporation) were applied to the transparent conductive films obtained in Examples 1 to 4 and Comparative Examples 1 and 2 The average surface resistance was determined by measuring the surface resistance 10 times using a Loresta-GP MCP-T610 (Mitsuibishi Chemical Corporation) (measuring range: 10 x 10 ^-2 to 10 x 10 ⁸ ). The sheet resistance uniformity was calculated using the standard deviation and is shown in Table 1 below.

Transparent conductive film Coating solution concentration (%) Permeability
(550 nm,%) Hayes
(%) Surface resistance
(Ω / sq.) Sheet resistance uniformity
(%) Silver nano
wire Conductive polymer Silicon polymer Example 1 0.1 0.3 1.0 91.2 1.0 222 10 Example 2 0.3 0.3 1.0 91.0 1.2 150 7 Example 3 0.5 0.3 1.0 90.8 1.3 78 7 Example 4 1.0 0.3 1.0 90.0 1.8 52 6 Comparative Example 1 0.3 0.3 Absenteeism 90.8 1.4 133 8 Comparative Example 2 0.3 Absenteeism 1.0 91.2 1.2 157 21

(3) Weatherability evaluation

The transparent conductive films obtained in Examples 1 to 4 and Comparative Examples 1 and 2 were subjected to the weathering resistance evaluation under the two conditions shown in Table 2 below. The results are shown in Tables 3 and 4 below.

Temperature() Humidity(%) time Weatherability evaluation 1 60 95 500h Weatherability evaluation 2 85 85 500h

Transparent conductive film Coating solution concentration (%) Permeability
(550 nm,%) Hayes
(%) Surface resistance
(Ω / sq.) Sheet resistance
Uniformity
(%) Rate of Change of Surface Resistance after Weathering Evaluation (%) Silver nano
wire Conductive polymer Silicon polymer Example 1 0.1 0.3 1.0 91.3 1.1 230 9 3.6 Example 2 0.3 0.3 1.0 91.0 1.3 161 7 7.3 Example 3 0.5 0.3 1.0 90.9 1.3 80 6 2.5 Example 4 1.0 0.3 1.0 90.0 1.9 55 7 5.8 Comparative Example 1 0.3 0.3 Absenteeism 89.8 2.1 1210 15 810 Comparative Example 2 0.3 Absenteeism 1.0 90.4 1.8 166 26 5.7

* Weatherability evaluation 1

Transparent conductive film Coating solution concentration (%) Permeability
(550 nm,%) Hayes
(%) Surface resistance
(Ω / sq.) Sheet resistance
Uniformity
(%) Rate of Change of Surface Resistance after Weathering Evaluation (%) Silver nano
wire Conductive polymer Silicon polymer Example 1 0.1 0.3 1.0 91.1 1.2 219 7 1.4 Example 2 0.3 0.3 1.0 91.3 1.3 158 8 5.3 Example 3 0.5 0.3 1.0 90.8 1.4 81 8 3.8 Example 4 1.0 0.3 1.0 89.9 1.8 56 9 7.7 Comparative Example 1 0.3 0.3 Absenteeism 89.5 2.0 987 22 642 Comparative Example 2 0.3 Absenteeism 1.0 90.7 1.7 170 31 8.3

* Weatherability evaluation 2

From the results of the surface resistance evaluation of the transparent conductive films of Examples 1 to 4 shown in Tables 3 and 4, it can be seen that the surface resistance decreases as the content of silver nanowires increases. In contrast, in Comparative Example 2, the transparent conductive film of Example 2 exhibited improved sheet resistance uniformity due to the conductive polymer.

On the other hand, from the results of the weather resistance evaluations 1 and 2 of Tables 3 to 4, it can be confirmed that the rate of change of sheet resistance of the transparent conductive films of Examples 1 to 4 is within 10%. Also, as compared with Comparative Example 1, the transparent conductive film of Example 2 shows that the electroconductive film is protected by the silicone-based polymer film and the environmental stability can be secured.

Claims (23)

Applying a solution containing a metal nanowire on one surface of a substrate, and applying a solution containing the conductive polymer to form an electroconductive film; And
And applying a silicon-based organic-inorganic hybrid polymer solution on the electroconductive film to form a silicon-based organic-inorganic hybrid polymer binder film,
Wherein the conductive polymer is one or a mixture of two or more selected from the group consisting of polyacetylene, polypyrrole, polyaniline, polythiophene, and derivatives thereof, and is contained in the solution in an amount of 0.5 to 5 wt%
Wherein the silicon-based organic-inorganic hybrid polymer is at least one member selected from the group consisting of polycarbosilane, polysilane, polysiloxane, polysilazane, and derivatives thereof, and 0.01 to 10 wt% of the silicone-based organic-inorganic hybrid polymer is contained in the solution. [4] The substrate according to claim 1, wherein the substrate is at least one polymer substrate selected from the group consisting of polyimide, polyethersulfone, polyetheretherketone, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyacrylate and polyurethane ≪ / RTI > The method of claim 1, wherein the metal nanowire is a silver nanowire, a copper nanowire, or a mixture thereof. The method of claim 1, wherein the metal nanowires have an average diameter in the range of 10 to 40 nm and an average length in the range of 10 to 50 μm. The method of claim 1, wherein the polythiophene conductive polymer is poly-3,4-ethylenedioxythiophene / polystyrene sulfonate (PEDOT / PSS). [Claim 2] The method according to claim 1, wherein the solution containing the metal nanowires is a solution in which metal nanowires are dispersed in water or alcohol in a solid content of 0.1 to 1.5 wt%. The method according to claim 1, wherein the step of forming the silicon-based organic-inorganic hybrid polymer binder film comprises: impregnating a silicon-based organic-inorganic hybrid polymer solution with a film on which the electrically conductive film has been formed; coating the substrate with a silicone- Forming a silicon-based organic-inorganic hybrid polymer film through a curing step and a curing step. [Claim 7] The method of claim 7, wherein the drying step is performed by drying the silicon-based organic-inorganic hybrid polymer film formed on the substrate at 80 DEG C to 400 DEG C for 2 minutes or more. [Claim 7] The method according to claim 7, wherein the curing step is performed by a temperature of 80 to 150 DEG C and a humidity of 80 to 95RH%, or an ultraviolet ray of 100 mJ to 1000 mJ. delete delete materials; An electrically conductive film including a metal nanowire formed on one surface of the substrate and a conductive polymer; And a silicon-based organic-inorganic hybrid polymer binder film formed on the electroconductive film,
Wherein the substrate comprises at least one polymeric substrate selected from the group consisting of polyimide, polyethersulfone, polyetheretherketone, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyacrylate and polyurethane,
The metal nanowires may be silver nanowires, copper nanowires or mixtures thereof,
Wherein the conductive polymer is one or a mixture of two or more selected from the group consisting of polyacetylene, polypyrrole, polyaniline, polythiophene and derivatives thereof,
Wherein the silicon-based organic-inorganic hybrid polymer is at least one transparent conductive film selected from the group consisting of polycarbosilane, polysilane, polysiloxane, polysilazane, and derivatives thereof,
Wherein the transparent conductive film is produced by the method for producing a transparent conductive film according to any one of claims 1 to 9. delete delete delete delete delete delete delete delete delete delete delete