KR20150118409A - Transparent conductive film using photo-curable composition for antioxidation - Google Patents

Abstract

A transparent conductive film according to the present invention comprises a substrate;
A metal coating or deposition layer deposited on the top surface of the substrate; And
And a film layer made of a photo-curing composition laminated on the upper surface of the metal coating or deposition layer,
The photo-curable composition may be an organic-inorganic hybrid sol-gel compound; And
A urethane acrylate oligomer or an acrylate monomer,
The organic-inorganic hybrid sol-gel compound is characterized by being at least one sol or gel state selected from silica, titanium oxide, alumina, magnesium oxide and zirconium oxide.

Description

(Transparent conductive film using photo-curable composition for antioxidation)

The present invention relates to a transparent conductive film coated with a photocurable composition for forming an antioxidant protective film, and more particularly, to provide a transparent conductive film which gives excellent optical characteristics, improved hardness and environmental resistance.

The transparent conductive film is a thin film electrode that imparts conductivity while maintaining transparency on the surface of a transparent insulating material such as a glass or a plastic film. The transparent conductive film is a thin film electrode which is used as a display such as a liquid crystal display (LCD), a plasma panel display (PDP), an organic light emitting diode In addition to the field, it has been applied to a wide range of fields such as touch panel, transparent electromagnetic wave shielding film, transparent heat emitting body, conductive glass, gas sensor, heat reflection coating film, solar battery, illumination and automobile.

In the past, ITO (Indium Tin Oxide) has been widely used as a transparent electrode material for various electronic devices such as an LCD panel, a PDP panel, a touch panel, an electronic paper, a solar cell, and an OLED panel. However, indium tin oxide film, which is a conductive transparent film that is exposed to various display materials, requires high cost equipment because it must be physically coated at high temperature and high pressure. In case of indium tin oxide film coated on plastic substrate, Mechanical stability is poor when the film is warped or folded, and electrical characteristics are changed due to thermal deformation due to a difference in thermal expansion coefficient between the substrate and the substrate.

For this reason, in recent years, some attempts have been made to introduce new transparent electrode materials in place of conventional ITO.

The transparent conductive film containing such a nanostructure has a problem of low environmental resistance due to low hardness of the film and easy reaction with various compounds. In addition, due to the influence of oxygen or moisture in the air exposed by long-term storage, the nano-structured metals are oxidized to deteriorate electrical characteristics.

An object of the present invention is to provide a transparent conductive film excellent in hardness, environmental resistance and optical characteristics while maintaining electrical contact properties.

According to an aspect of the present invention,

A metal coating or deposition layer formed on an upper surface of the substrate; And

And a film layer made of a photocurable composition formed on the upper surface of the metal coating or deposition layer,

The photo-curable composition may be an organic-inorganic hybrid sol-gel compound; And

A urethane acrylate oligomer or an acrylate monomer,

Wherein the organic-inorganic hybrid sol-gel compound is at least one sol or gel state selected from silica, titanium oxide, alumina, magnesium oxide and zirconium oxide.

According to a preferred aspect of the present invention, the urethane acrylate oligomer is preferably an aliphatic urethane acrylate oligomer having 3 to 15 functional groups.

According to a further preferred feature of the present invention, it is preferable that the acrylate monomer is at least one selected from the group consisting of epoxy acrylate, ester acrylate, silicone acrylate and alkyl acrylate.

According to a further preferred feature of the present invention, the photocurable composition comprises 1 to 6% by weight of an organic-inorganic hybrid sol-gel compound and 1 to 6% by weight of a urethane acrylate oligomer or acrylate monomer based on the total weight of the composition .

According to an even more preferred feature of the present invention, it is preferred that the photocurable composition comprises 90 to 95% by weight of solvent and 0.1 to 1% by weight of photocuring agent, based on the total weight of the composition.

According to a further preferred feature of the present invention, the solvent is preferably at least one selected from the group consisting of an alcohol-based, amine-based and ketone-based solvent.

According to a further preferred feature of the present invention, it is preferable that the photocuring agent is at least one selected from the group consisting of a ketone type, a phosphine type, a benzophenone type, a sulfide type and a phosphine oxide type.

According to an even more preferred feature of the present invention, the photo-curable composition further comprises 0.1 to 1% by weight of an additive based on the total weight of the composition, wherein the additive comprises a surfactant, a leveling agent, a wetting agent, a slip agent, And a UV stabilizer.

According to an even more preferred feature of the present invention, the substrate is preferably a polyethylene terephthalate film.

According to a further preferred feature of the invention, the metal coating or deposition layer preferably comprises a nanostructured metal, a water soluble binder, a solvent and an additive.

According to a further preferred feature of the present invention, the metal is preferably at least one selected from silver, gold, platinum, tin, iron, nickel, cobalt, aluminum, zinc, copper, indium and titanium.

According to a further preferred feature of the present invention, it is preferable that the water-soluble binder is at least one selected from urethane-based, acrylic-based, methylcellulose-based and carboimide-based ones.

According to an even more preferred feature of the invention, the additive is preferably a dispersing agent or a surfactant or a mixture thereof.

The transparent conductive film according to the present invention exhibits an excellent effect in improving the optical properties, hardness and environmental resistance while maintaining electrical properties.

FIG. 1 (a) is an SEM image showing particles of an organic-inorganic hybrid sol-gel used as an example, and FIG. 1 (b) is an SEM image showing a surface of a transparent conductive film prepared in Example 1. FIG.
FIG. 2 is a perspective view showing a transparent conductive film manufactured through Example 1. FIG.

Hereinafter, preferred embodiments of the present invention and physical properties of the respective components will be described in detail with reference to the accompanying drawings. However, the present invention is not limited thereto, And this does not mean that the technical idea and scope of the present invention are limited.

The transparent conductive film according to the present invention comprises a substrate, a metal coating or deposition layer formed on the upper surface of the above-mentioned substrate, and a transparent conductive film including a film layer made of the photocurable composition formed on the upper surface of the above- Inorganic hybrid sol-gel compound and a urethane acrylate oligomer or an acrylate monomer, and the above-described organic-inorganic hybrid sol-gel compound includes silica, titanium oxide, alumina, magnesium oxide And zirconium oxide.

It is preferable that the substrate is a polyethylene terephthalate film having a thickness of 50 to 188 μm, and it is preferable to treat the surface so that the metal nanowire can be coated. Specifically, the surface treatment with an index matching coating film or a hard coating film desirable.

Said metal coating or deposition layer is formed on the top surface of said substrate and comprises 0.1 to 1% by weight of metal of nanostructure, 0.1 to 1% by weight of water soluble binder, 80 to 90% by weight of solvent and 8 to 18% .

More specifically, the above-mentioned metal is preferably at least one selected from silver, gold, platinum, tin, iron, nickel, cobalt, aluminum, zinc, copper, indium and titanium, more preferably silver. The above-mentioned water-soluble binder is preferably at least one selected from the group consisting of urethane-based, acrylic-based, methylcellulose-based and carboimide-based ones, and the above-mentioned solvent is preferably purified water. The above-mentioned additives are preferably dispersants, surfactants, or mixtures thereof, and may further include antioxidants, ultraviolet stabilizers, antifoaming agents, leveling agents, and the like within the range not impairing the effects of the present invention. Specifically, the above-mentioned dispersing agent may be acrylic or the like, and the above-mentioned surfactant may be a silicone, an epoxy, a modified silicone, an acrylic, an ether or a fluorine.

The above-mentioned film layer is formed on the upper surface of the above-mentioned metal coating or vapor deposition layer and is preferably composed of a photo-curable composition. The above-mentioned photo-curable composition can be produced by mixing an organic-inorganic hybrid sol-gel compound and a urethane acrylate oligomer or acrylate It is preferred to include monomers.

More specifically, the above-mentioned organic-inorganic hybrid sol-gel compound preferably contains 1 to 6% by weight based on the total weight of the composition. When the amount is less than 1% by weight, the electrode layer is protected If the content is more than 6% by weight, the hardness is increased but the function as a transparent conductive film is lost due to overprotection of the electrode layer. . More specifically, the above-mentioned organic-inorganic hybrid sol-gel compound is chemically very stable, and has excellent characteristics such as corrosion resistance and abrasion resistance. When used singly, a coating film having high hardness is not formed. Or an acrylate monomer.

The above-mentioned urethane acrylate oligomer preferably contains 1 to 6% by weight based on the total weight of the composition. When used in combination with the above-described organic-inorganic hybrid sol-gel compound, the urethane acrylate oligomer has a role of forming a high- do. Specifically, the urethane acrylate oligomer is preferably an aliphatic urethane acrylate oligomer having 3 to 15 functional groups. When the functional group of the oligomer is less than 3, it has a problem that the hardness is lowered. As the functional group is increased, Which is a strong cause of the formation of a coating film, which can hinder electrical characteristics.

The above-mentioned acrylate monomers are preferably at least one selected from the group consisting of epoxy acrylates, ester acrylates, silicone acrylates and alkyl acrylates, more preferably alkyl acrylates.

The photocurable composition described above preferably comprises 90 to 95% by weight of solvent and 0.1 to 1% by weight of photocuring agent based on the total weight of the composition. More specifically, the solvent is preferably at least one selected from the group consisting of alcohol, amine and ketone, but is not limited thereto. In addition, the above-mentioned photo-curing agent has a function of binding bonds of the composition, and specifically, it is preferably at least one selected from the group consisting of ketone type, phosphine type, benzophenone type, sulfide type and phosphine oxide type.

The photocurable composition preferably contains 0.1 to 1% by weight of an additive. When the content is less than 0.1% by weight, a wet film is not formed. When the content exceeds 1% by weight, .

The above-mentioned additives are preferably at least one selected from the group consisting of a surfactant, a leveling agent, a wetting agent, a slip agent, a heat stabilizer and a UV stabilizer. Specific examples of the above additives include, but are not limited to, .

More specifically, the above-mentioned surfactants may be silicon, epoxy, modified silicone, acrylic, ether, and fluorine. The leveling agent may be a sulfonic acid-based or silicone-based surfactant. As the wetting agent, a silicone system, a fluorine system, or the like can be used. The above-mentioned heat stabilizer may be a Cd / Ba / Zn system, a Cd / Ba system, a Ba / Zn system, a Ca / Zn system, a Na / Za-based, Sn-based, Pb-based, Cd-based, Zn-based, and the like can be used. The ultraviolet stabilizer described above can use Benzophenone or Benzotriazole.

Hereinafter, a transparent conductive film according to an embodiment of the present invention will be described.

≪ Examples 1 to 4 >

Preparation of photocurable composition

A silica sol, a urethane acrylate oligomer or an acrylate monomer, a solvent and an additive were charged and stirred at 500 rpm for 5 minutes using a stirrer (TOKYO RIKAKKAI, NZ-1100) to prepare a photocurable composition. (The content of each component is shown in Table 1 below).

Production of transparent conductive film

Bar coating was performed by applying a metal composition on a substrate, and the above-described photo-curing composition was coated thereon to form a bar coating. Then, a transparent conductive film was prepared through photo-curing using a UV curing machine.

(The substrate was polyethylene terephthalate (PET) film, Toray Advanced Material Co., U43R), and an index matching coating was applied to the film to obtain a substrate having a transmittance of 92.5%.

As the metal composition, a solution composed of 86.5 g of purified water, 0.5 g of hydroxypropylmethyl cellulose system, 0.5% of silver nanowire, 12 g of dispersion and 1 g of fluorine surfactant was used.

≪ Comparative Examples 1 and 2 &

In the preparation of the photocurable composition, a urethane acrylate oligomer or an alkyl acrylate monomer, a solvent and an additive were added. (The content of each component is shown in Table 1 below).

≪ Comparative Example 3 &

A transparent conductive film was prepared in the same manner as in the above-mentioned example except that the above-described photocurable composition was not coated.

In each of the test examples, evaluation items of the physical properties and measurement methods thereof are as follows.

(1) Light transmittance (%) and turbidity: Nippon Denshoku Indusries Co. LTD, NDH-5000 at room temperature.

(2) Electrical Conductivity (ohm / sq): 4 point-probe method was used. The transparent conductive film was divided into 9 equal parts and each sheet resistance was measured using Mitsubishi Chemical Corporation, Loresta-GP and MCP-T600 The mean value was calculated.

(3) Environmental resistance test: The sheet resistance value after 0 hours and 240 hours at a temperature of 85 ° C and a humidity of 85% was measured, and the amount of change was measured.

(4) Hardness: The test was carried out using a pencil of each type 6B to 2H using a tester complying with a pencil scratch tester for coating film (JIS-K-5401), and the film surface of the test sample after the test was visually observed Respectively.

<Test Example>

The properties of the transparent conductive films prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were measured, and the results are shown in Table 2.

As can be seen from Table 2, the transparent conductive films prepared in Examples 1 to 4 have improved light transmittance and turbidity compared to Comparative Examples 1 to 3. In the case of Comparative Example 3 in which the photo-curing composition is not coated The light transmittance and turbidity are improved, but the hardness is remarkably lowered, which is not preferable.

In addition, it can be seen that the transparent conductive film prepared in Examples 1 to 4 has a small change amount (?) Of the sheet resistance value and is also effective in environmental resistance.

Therefore, the transparent conductive film according to the present invention exhibits an excellent effect in improving the optical properties, hardness and environmental resistance while maintaining electrical properties.

10: film layer
20: metal coating or deposition layer
30: Index matching coating film
40: substrate

Claims (13)

Board;
A metal coating or deposition layer formed on an upper surface of the substrate; And
And a film layer made of a photocurable composition formed on the upper surface of the metal coating or deposition layer,
The photo-curable composition may be an organic-inorganic hybrid sol-gel compound; And
A urethane acrylate oligomer or an acrylate monomer,
Wherein the organic-inorganic hybrid sol-gel compound is at least one sol or gel state selected from silica, titanium oxide, alumina, magnesium oxide and zirconium oxide. The method according to claim 1,
Wherein the urethane acrylate oligomer is an aliphatic urethane acrylate oligomer having 3 to 15 functional groups. The method according to claim 1,
Wherein the acrylate monomer is at least one selected from the group consisting of epoxy acrylate, ester acrylate, silicone acrylate and alkyl acrylate. The method according to claim 1,
Wherein the photo-curable composition comprises 1 to 6% by weight of an organic-inorganic hybrid sol-gel compound and 1 to 6% by weight of a urethane acrylate oligomer or an acrylate monomer, based on the total weight of the composition. The method according to claim 1,
Wherein the photocurable composition comprises 90 to 95% by weight of a solvent and 0.1 to 1% by weight of a photocuring agent based on the total weight of the composition. 6. The method of claim 5,
Wherein the solvent is at least one selected from alcohol-based, amine-based, and ketone-based solvents. 6. The method of claim 5,
Wherein the photo-curing agent is at least one selected from the group consisting of a ketone-based, phosphine-based, benzophenone-based, sulfide-based, and phosphine oxide-based. The method according to claim 1,
The photocurable composition further comprises 0.1 to 1% by weight of an additive, based on the total weight of the composition,
Wherein the additive is at least one selected from the group consisting of a surfactant, a leveling agent, a wetting agent, a slip agent, a heat stabilizer and a UV stabilizer. The method according to claim 1,
Wherein the substrate is a polyethylene terephthalate film. The method according to claim 1,
Wherein the metal coating or deposition layer comprises a nanostructured metal, a water soluble binder, a solvent, and an additive. 11. The method of claim 10,
Wherein the metal is at least one selected from silver, gold, platinum, tin, iron, nickel, cobalt, aluminum, zinc, copper, indium and titanium. 11. The method of claim 10,
Wherein the water-soluble binder is at least one selected from the group consisting of urethane-based, acrylic-based, methylcellulose-based, and carbomide-based. 11. The method of claim 10,
Wherein the additive is a dispersant, a surfactant, or a mixture thereof.

Images