KR101367729B1 - Etchant for conductive polymer membrane and method for patterning conductive polymer membrane using the same - Google Patents

Abstract

The present invention relates to an etching solution for a conductive polymer film having excellent etching ability with respect to a film coated with a conductive polymer material, and a method for patterning a conductive polymer film using the same, wherein the etching solution according to the present invention comprises an electrode film, an electromagnetic shielding layer, and a touch. It can be usefully used for the etching process of the conductive film for panels.

Description

Etching solution for conductive polymer film and method for patterning conductive polymer film using same {ETCHANT FOR CONDUCTIVE POLYMER MEMBRANE AND METHOD FOR PATTERNING CONDUCTIVE POLYMER MEMBRANE USING THE SAME}

The present invention relates to an etchant for a conductive polymer film having excellent etching ability with respect to a film coated with a conductive polymer material and a method for patterning a conductive polymer film using the same.

Currently, polyaniline (Polyaniline, PAN), polypyrrol (PPy), and polythiophene (PT) are widely used as conductive polymer compounds. They are easy to polymerize, have very good conductivity, thermal stability and oxidation stability.

By applying the electrical properties of these conductive polymer compounds, the possibility of use in various applications, such as the electrode of the secondary battery, electromagnetic shielding material, flexible electrode, antistatic material, anti-corrosion coating material has been proposed, but difficult processing, thermal and atmospheric Due to problems of instability, environmental resistance, and price, they are not actively commercialized.

However, recently, as the dust adhesion prevention and antistatic coating materials have attracted attention, the conductive polymer compounds have been attracting attention as the electromagnetic wave shielding coating material of various electronic devices by strengthening the standard for electromagnetic shielding.

In particular, the conductive polymer is attracting attention as a conductive coating on the glass surface of the CRT, as described in US Patent Nos. 5,035,926 and 5,391,472, polyethylene dioxythiophene (PEDT) is a polythiophene-based conductive polymer Since it is known. Such conductive polymers exhibit excellent transparency compared to polyaniline-based and polypyrrole-based as well as other polythiophene-based conductive polymers.

The polythiophene-based conductive polymer may be typically doped with polyethylene dioxythiophene, specifically, polyethylene dioxythiophene, and polystyrene sulfonate. Examples of such water-dispersible polyethylene dioxythiophene include Clevios P, currently sold by Heraeus. Is representative. However, in the use of such a polymer film using such a conductive polymer coating composition, there is a continuing need for a conductive polymer film in which a precise pattern is etched and the pattern is difficult to be seen after etching.

Accordingly, the present inventors completed the present invention by discovering that an etching solution containing a chlorine compound exhibits excellent etching ability with respect to the conductive polymer film, and when the conductive polymer film is patterned using the photolithography method, the pattern is hardly seen.

[Patent Document 1] US Patent No. 5,035,926

[Patent Document 2] US Patent No. 5,391,472

An object of the present invention is to provide an etching liquid for conductive polymer films having excellent etching ability.

Another object of the present invention is to provide a method for patterning a conductive polymer film by photolithography using the etching solution for the conductive polymer film.

In order to achieve the above object, the present invention comprises a chlorine compound and a solvent, the chlorine compound provides an etching solution for a conductive polymer film, characterized in that it comprises an amount of 0.5 to 50% by weight based on the total weight of the etching solution. .

In order to achieve the above another object, the present invention provides a method for patterning a conductive polymer film by a photolithography method using the etching liquid for the conductive polymer film.

The etching solution for the conductive polymer film including the chlorine compound according to the present invention has excellent etching ability with respect to the conductive polymer film, and when the conductive polymer film is patterned by the photolithography method, the pattern is hard to be seen. ) Upper and lower electrode films, inorganic electroluminescent element (EL) electrode films for mobile phones or transparent electrode films for displays, electromagnetic shielding layers on TV CRT tubes and computer monitor screens, and conductive films for touch panels for electronic and electronic device components. It can be used to etch the conductive polymer film used for the like.

1 is a diagram illustrating a method of patterning a conductive polymer film by a photolithography method using an etching solution for a conductive polymer film according to the present invention.
1: Substrate for Coating Composition
2: coating conductive polymer coating composition on substrate
3: applying a resist on a polymer film using a conductive polymer coating composition
4: Selectively Exposing Resist Using Mask
5: Remove the resist of the changed part using developer
6: remove conductivity of the exposed conductive polymer film using an etching solution for the conductive polymer film
7: Remove remaining resist film through stripping process

The present invention includes a chlorine compound and a solvent, the chlorine compound provides an etching solution for a conductive polymer film, characterized in that it comprises an amount of 0.5 to 50% by weight based on the total weight of the etching solution.

The etching solution according to the present invention not only has excellent liquid stability, but may also exhibit excellent etching properties and visibility when the conductive polymer film is etched using the etching solution. In addition, the etching solution does not have any influence on the remaining conductive polymer film (conductive layer) even after the etching process is completed.

The chlorine compound in the present invention is characterized in that it is selected from the group consisting of sodium dichloroisocyanurate (C ₃ C _{1 2} N ₃ NaO ₃ ), sodium hypochlorite (NaOCl) and mixtures thereof.

The chlorine compound may be included in an amount of 0.5 to 50% by weight, preferably 1 to 30% by weight based on the total weight of the etching solution. If the etching solution contains less than 0.5% by weight of the chlorine compound, the etching is not good, and if included in an amount exceeding 50% by weight may cause a problem of poor liquid stability.

Although it does not restrict | limit especially as a solvent of the etching liquid of this invention, Distilled water is preferable.

The etching solution according to the present invention can be used to etch a conductive polymer film, for example, a polythiophene-based, polyaniline-based or polypyrrole-based conductive polymer film, and preferably to etch a polythiophene-based conductive polymer film.

The conductive polymer film is characterized in that the conductive polymer coating composition is applied to the substrate and then dried, wherein the conductive polymer coating composition is a conductive polymer, alcohol-based organic solvents, amide-based organic solvents, polyester, polyurethane, It may include a binder selected from the group consisting of polyacrylic resins, alkoxy silanes and mixtures thereof.

The alcohol-based organic solvent may be selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol and mixtures thereof. The amide organic solvent may be formamide, N-methylformamide, N, N-dimethylformamide, Acetamide, N-methylacetamide, N-methylpyrrolidone and mixtures thereof. In addition, the polyester and the polyurethane used as the binder can be used as long as it is commonly used in the art, the alkoxy silane is preferably a tri- and tetra-functional silane compound, more preferably trimethoxysilane and tetra Ethoxysilane can be used.

The conductive polymer is a polythiophene-based, polyaniline-based or polypyrrole-based conductive polymer, preferably a polythiophene-based conductive polymer, more preferably polyethylenedioxythiophene (PEDT) -based conductive polymer, most preferably polyethylenedioxythiophene The polystyrene sulfonate may be doped.

Examples of the substrate may be a substrate made of a transparent material, preferably, a substrate selected from the group consisting of glass, cast polypropylene (CPP) film, polyethylene terephthalate film, polycarbonate and acrylic panel. .

The coating method of the conductive polymer coating composition may be performed by a method known in the art, for example, bar coating, roll coating, flow coating, dip coating or spin coating may be used. Drying can be carried out for 1 to 10 minutes at a temperature of 100 to 145 ℃. The conductive polymer film prepared by the coating and drying preferably has a thickness of 1 to 5 탆.

According to one embodiment of the present invention, after applying the conductive polymer coating composition (for example, polythiophene-based conductive polymer coating composition) to a transparent substrate (for example, polyethylene terephthalate film) by a bar coating method, By drying in an oven at a temperature of about 125 ° C. for about 5 minutes, polythiophene-based conductive polymer membranes up to 5 μm thick can be prepared.

The present invention also provides a method for patterning a conductive polymer film by a photolithography method using the etching solution for the conductive polymer film.

The photolithography method comprises the steps of: 1) applying a resist on the conductive polymer film or laminating the dry film resist; 2) selectively exposing the resist using a mask; 3) removing the changed portion of resist using a developer; 4) removing conductivity of the exposed conductive polymer film using an etching solution for the conductive polymer film; And 5) removing the remaining resist film through the peeling process.

The method is performed by applying a resist on the surface of the conductive polymer film (conductive layer) and removing a portion selectively changed by light using a developer. At this time, the case where the light-receiving part melts well in the developer is called a positive resist and vice versa. Dry film resists can also be used. The type and application method of the resist are well known in the art, and are not particularly limited.

The thickness of the resist coating film obtained in the film formation process of step 1) is 0.5-10 micrometers, and when laminating a dry film resist, thickness is not specifically limited.

After performing step 1) above to form a resist film (ie, before performing step (2)), soft baking may be performed to remove the remaining organic solvent. This may be done to prevent contamination due to residual solvents and to keep the reaction characteristics of the resist constant, and it is preferable to perform soft bake at a heating temperature of 60 to 140 ° C.

In step 2), the resist can be selectively exposed by performing an exposure step of selectively irradiating light using a mask.

In step 3), the developer can be used to remove the changed portions of the resist. The developer may be an aqueous solution of an alkali (eg, tetraalkylammonium hydroxide, sodium hydroxide or potassium hydroxide, sodium carbonate) commonly used in the art related to the present invention. After the developing process of step 3), if necessary, the hard bake process may be performed at a heating temperature of 80 to 180 ° C.

In step 4), the conductivity of the conductive polymer film exposed by the etching solution may be removed using the etching solution for the conductive polymer film of the present invention. The above process may be performed by immersing the conductive polymer film in the etching solution of the present invention. At this time, only the conductivity is removed and the conductive polymer film remains as it is, which is due to the principle that the etching solution loses the conductivity by chemically changing the structure of the conjugated bond of the conductive polymer by oxidizing the conductive polymer film. The method of the present invention can secure the invisibility of the pattern in a manner different from the patterning process of etching the conductive polymer film to lose the conductivity.

The conductive polymer membrane etching solution according to the present invention may be used after dilution in distilled water, preferably after dilution in distilled water at a concentration of 1 to 30% by weight. The temperature of the said etching liquid is 10-80 degreeC, Preferably it is 20-60 degreeC.

In the present invention, the time required for the etching process may be 0.1 to 30 minutes, preferably 0.3 to 20 minutes.

In step 5), the remaining resist film may be removed from the conductive polymer film subjected to the etching process through a peeling process, wherein a peeling solution including an organic solvent, an amine compound and an ammonium salt may be used in the peeling process. Subsequently, when the membrane is washed with distilled water or the like, the printed surface is etched to complete the print pattern.

The organic solvent may be selected from the group consisting of, for example, dimethyl sulfoxide, ethylene carbonate and mixtures thereof, and the amine compound may be, for example, N-methylpyrrolidone, N, N-methylformamide, acetamide, N -Methylacetamide and mixtures thereof.

In the method of the present invention, the developing process or the peeling process may be performed by dipping or spraying, but is not limited thereto.

According to one embodiment of the present invention, as shown in FIG. 1, a substrate for preparing a conductive polymer coating composition is prepared (1). The conductive polymer coating composition is applied to the substrate and dried to prepare a conductive polymer film (2). The resist is applied onto the conductive polymer film prepared above (3). The resist is selectively exposed using a mask (4). The resist of the changed portion is removed using a developer (5). An etching solution containing a chlorine compound according to the present invention is used to remove the conductivity of the exposed conductive layer polymer film (6). The remaining resist film is removed through the peeling process (7). When the membrane is washed with distilled water or the like, the printed surface is etched to complete the print pattern.

Therefore, the etching solution according to the present invention is an electrode film, an electromagnetic shielding layer or a conductive film for a touch panel, specifically, an upper and lower electrode film for a contact panel, an inorganic electroluminescent device (EL) electrode film for a mobile phone, or a transparent electrode for a display. It can be used to etch conductive polymer films used for films, TV CRT surfaces and electromagnetic shielding layers of computer monitor screens, and conductive films for touch panels for electronic and electronic component parts.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are only intended to illustrate the present invention and are not intended to limit the present invention.

Examples 1-9 and Comparative Examples 1-7

Using the etchant and its content range shown in Table 1 below, it was mixed with distilled water to prepare a conductive polymer etching solution.

Test Example

A conductive polymer coating composition was prepared in a conventional manner using a conductive polymer doped with polyethylenedioxythiophene polystyrene sulfonate, methanol, propanol, N-methylacetamide and trimethoxysilane. The conductive polymer coating composition prepared above was applied to a polyethylene terephthalate film and dried in an oven at about 125 ° C. for about 5 minutes to prepare a conductive polymer membrane. The dried polymer membrane had a thickness of 5 μm or less.

1) Etchability

The conductive polymer film prepared above was patterned by photolithography using the conductive polymer etching solution prepared in Examples and Comparative Examples.

Specifically, in the photolithography method, a resist is applied on the conductive polymer film to a thickness of about 2 to 4 μm, and soft baking is performed at a heating temperature of 120 ° C. Selectively exposing the resist using a mask, removing the resist of the changed portion using a developer, performing a hard bake process at a heating temperature of 140 ° C., and then conducting the conductive polymer film exposed using an etchant for a conductive polymer film. It was patterned by removing, and after washing with distilled water, the surface resistance was measured to confirm the etching property.

Etchability was measured by using a high resistance measuring instrument (Trustat Worksurface Tester ST-3, SIMCO), it was determined that the etching was more than 10 ¹³ Ω / ㅁ. The etching time was defined as follows.

○: less than 20 minutes

△: less than 20 to 30 minutes

×: 30 minutes or more

2) Stability of Etching Solution

The stability of the etching solution was evaluated according to the degree of agglomeration after leaving the conductive polymer etching solution prepared in Examples and Comparative Examples for 5 days at room temperature, it was good if the agglomeration did not, it was represented as poor. In the following Table 1, when the etching property did not come out and the stability was not evaluated, it was described as −.

3) visibility

The visibility should be confirmed by the difference in chromaticity unlike the ITO film (Film). Therefore, the UV-Spectrometer (CM-3500d, Minolta) is used to measure the transmittance at 550 nm wavelength. b ^* was determined as a difference, which was defined as follows.

Δb ^* <1.5: good (pattern is hard to see)

△ b ^* 〉 1.5: Poor (Pattern is visible)

In the following Table 1, when the etching property did not come out and the visibility was not evaluated, it was described as-.

In addition, when the surface resistance value of the conductive layer did not change after the completion of the etching process, it was confirmed that the etching liquid did not have any influence on the remaining conductive layer.

Table 1 shows the results of etching, stability and visibility of the etching solution measured by the same method as described above.

Furtherance Etching solution (solid content, weight%) Etching time Etch solution stability Δb * Example 1 C ₃ Cl ₂ N ₃ NaO ₃ (30) ○ Good Good Example 2 C ₃ Cl ₂ N ₃ NaO ₃ (40) ○ Good Good Example 3 C ₃ Cl ₂ N ₃ NaO ₃ (45) ○ Good Good Example 4 NaOCl (25) ○ Good Good Comparative Example 1 (NH ₄ ) ₂ Ce (NO ₃ ) ₆ (35) ○ Good Bad Comparative Example 2 NaClO ₃ (40) × - - Comparative Example 3 Na ₂ SO ₃ (25) × - - Comparative Example 4 KMnO ₄ (35) × - - Comparative Example 5 Ce (SO) ₄ (30) × - - Comparative Example 6 NaHSO ₃ (45) × - - Comparative Example 7 C ₃ Cl ₂ N ₃ NaO ₃ (55) ○ Bad Good Comparative Example 8 C ₃ Cl ₂ N ₃ NaO ₃ (65) ○ Bad Good Comparative Example 9 C ₃ Cl ₂ N ₃ NaO ₃ (80) ○ Bad Good C ₃ Cl ₂ N ₃ NaO ₃ : Dichloroisocyanurate sodium (from Aldrich)
(NH ₄ ) ₂ Ce (NO ₃ ) ₆ : ammonium nitrate cerium (Ammonium Cerium Nitrate, product of Aldrich)
NaOCl: Hypochlorite Sodium (Sodium Hypochlorite, manufactured by Aldrich)
NaClO ₃ : Chlorate Sodium (Sodium Chlorate, product of Aldrich)
Na ₂ SO ₃ : Sodium Sulfite (manufactured by Aldrich)
KMnO ₄ : Potassium Permanganate (Potassium Permanganate, manufactured by Aldrich)
Ce (SO) ₄ : Sulfate Cerium (Cerium Sulfate, Aldrich)
NaHSO ₃ : Sodium Bisulfite (manufactured by Aldrich)
Solvent: Use distilled water

As shown in Table 1, it was found that the visibility is poor by using the etching solution containing the ammonium cerium nitrate (Ammonium cerium nitrate) used in the etching of the conventional conductive polymer film (Comparative Example 1). In addition, when the etching solutions of Comparative Examples 2 to 6 were used, it was confirmed that etching was not performed even for 20 minutes or more when the conductive polymer film was immersed. Moreover, even if it contained a chlorine compound, it turned out that the etching liquid contained in excess of 50 weight% or more is poor in liquid stability.

Claims (18)

Sodium dichloroisocyanurate (C ₃ C _{1 2} N ₃ NaO ₃ ) and a solvent, wherein the dichloroisocyanurate sodium is included in an amount of 0.5 to 50% by weight based on the total weight of the etching solution. Etching liquid for conductive polymer films. delete The method of claim 1,
The sodium dichloroisocyanurate is contained in an amount of 1 to 30% by weight based on the total weight of the etching solution, etching liquid for a conductive polymer film. The method of claim 1,
Etching liquid for a conductive polymer film, characterized in that the solvent is distilled water. The method of claim 1,
The conductive polymer film is prepared by applying a conductive polymer coating composition to the substrate and then dried, the etching solution for a conductive polymer film. 6. The method of claim 5,
The conductive polymer is a polythiophene-based, polyaniline-based or polypyrrole-based conductive polymer, characterized in that the etching liquid for a conductive polymer film. 6. The method of claim 5,
The conductive polymer is a polyethylene dioxythiophene (PEDT) characterized in that the polystyrene sulfonate is doped, the conductive polymer film etching solution. 6. The method of claim 5,
The drying is performed for 1 to 10 minutes at a temperature of 100 to 145 ℃, etching liquid for a conductive polymer film. 6. The method of claim 5,
Etching liquid for a conductive polymer film, characterized in that the conductive polymer film is 1 to 5 ㎛ thick. The method of claim 1,
The conductive polymer film is used for an electrode film, an electromagnetic shielding layer or a conductive film for a touch panel, the etching liquid for a conductive polymer film. A method for patterning a conductive polymer film by photolithography using the etching solution for the conductive polymer film according to any one of claims 1 and 3 to 10. The method of claim 11,
The above method
1) applying a resist on the conductive polymer film or laminating the dry film resist;
2) selectively exposing the resist using a mask;
3) removing the changed portion of resist using a developer;
4) removing conductivity of the exposed conductive polymer film using an etching solution for the conductive polymer film; And
5) removing the remaining resist film through the peeling process
&Lt; / RTI &gt; 13. The method of claim 12,
The thickness of the resist coating film formed in step 1) is 0.5 to 10 ㎛. 13. The method of claim 12,
Before performing step 2), characterized in that the soft bake process at a heating temperature of 60 to 140 ℃. 13. The method of claim 12,
The developing solution of step 3) is an aqueous alkali solution. 13. The method of claim 12,
After performing step 3), further comprising performing a hard bake process at a heating temperature of 80 to 180 ℃. 13. The method of claim 12,
Etching solution is applied for 0.1 to 30 minutes in the step 4). 13. The method of claim 12,
The organic solvent selected from the group consisting of dimethyl sulfoxide, ethylene carbonate and a mixture thereof; Amine compounds selected from the group consisting of N-methylpyrrolidone, N, N-dimethylformamide, acetamide, N-methylacetamide and mixtures thereof; And a stripping solution containing an ammonium salt.

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