KR20080018678A - Conductive polymer coating composition, preparation method of coating film using the same and the coating film - Google Patents

Abstract

A conductive polymer coating composition for a protective film is provided to impart anti-fouling property and printability to a protective film at the same time, thereby improving cost- and time-efficiency. A conductive polymer coating composition for a protective film comprises: 1-30 wt% of a water dispersion of conductive polymer including a polythiophene-, polypyrrole- or polyaniline-based polymer or a mixture thereof; 5-25 wt% of a water soluble binder resin; 5-40 wt% of an alcohol solvent; 5-30 wt% of a functional organic solvent; water; 0.1-10 wt% of water soluble olefin wax; and 0.001-5 wt% of a fluororesin.

Description

Conductive polymer coating composition, manufacturing method of coating film using same and coating film thereof {conductive polymer coating composition, preparation method of coating film using the same and the coating film}

The present invention relates to a conductive polymer coating composition, a method for manufacturing a coating film using the same and a coating film thereof, and more particularly, to a conductive polymer coating composition for a protective film and a method for producing a coating film having improved pollution control performance and printability using the same. And a coating film thereof.

The surface protection film is attached on the surface of the member to protect the surface of the member. In general, in the manufacturing process of a display device such as an LCD, a protective film is adhered on the outermost surface of the liquid crystal panel, for example, in order to prevent damage to the surface of the polarizing plate. Finger marks, fingerprints or other stains may be attached onto the surface protection film, and dust or dust may be attached by charging. Therefore, the surface protection film needs a pollution control performance and an antistatic performance that can easily wipe off such stains.

On the other hand, there are many kinds of polarizing plates with a surface protection film, depending on the purpose of use. In order to distinguish them, the product name or axial direction may be displayed on each sheet, and necessary information may be provided by a barcode. The surface protective film attached in this case requires the performance opposite to the pollution control performance, that is, printability, so that the ink does not fall well even when spreading and wiping lightly.

Conventional surface protection film to solve the problem by forming a charge layer having an antistatic function on the plastic substrate such as PET to achieve the above performance, and to form a layer having a pollution control performance and printability thereon (Republic of Korea Patent No. 2003-0012766), although a surfactant in the form of a quaternary ammonium divalent salt was used as an antistatic main material of the film, the surface protective film is an antistatic as a protective film for a high specification display such as TFT-LCD. There is a limit to the function.

Accordingly, an object of the present invention is to provide a conductive polymer coating composition that can provide both pollution control performance and printability to the protective film.

Another object of the present invention is to provide a simple and convenient method for producing a conductive polymer coating film that can reduce the cost and time caused by two coating processes using the coating composition.

Another object of the present invention to provide a conductive polymer coating film prepared by the above method.

 In the present invention to achieve the above object,

Conductive polymer aqueous dispersions containing polythiophene-based, polypyrrole-based, polyaniline-based high molecular compounds or mixtures thereof; Water-soluble binder resins; Alcohol solvents; Organic solvents; water; Water-soluble olefin waxes; And a conductive polymer coating composition comprising a fluorine resin.

In addition, in order to achieve another object of the present invention,

Coating the conductive polymer coating composition on a substrate; And it provides a method for producing a conductive polymer coating film comprising the step of drying the coated composition.

In addition, for another object of the present invention there is provided a coating film prepared by the method for producing a conductive polymer coating film.

According to one embodiment of the present invention, the conductive polymer coating composition is 1 to 30% by weight of the conductive polymer aqueous dispersion; 5 to 25% by weight of the water-soluble binder resin; 5-40% by weight of alcohol solvent; 5-30% by weight of a functional organic solvent; 10-50% by weight of water; 0.1 to 10% water soluble olefin wax; And 0.001 to 5% of a fluorine resin.

According to another embodiment of the present invention, in the conductive polymer coating composition, the conductive polymer aqueous dispersion preferably includes polyethylene dioxythiophene (polyethylendioxithiophene; PEDOT).

According to another embodiment of the present invention, the water-soluble binder resin in the conductive polymer composition is a polyurethane, polymethyl methacrylate, polyacrylate, polyvinyl alcohol, polyvinyl acetal, polyvinylacetate, and mixtures thereof It is preferably selected from the group consisting of.

According to another embodiment of the invention, the water-soluble olefin wax in the conductive polymer composition is preferably selected from the group consisting of ethylene wax, propylene wax and mixtures thereof.

According to another embodiment of the present invention, the fluororesin in the conductive polymer composition is polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polychlorotrifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer , Ethylene tetrafluoroethylene copolymer, ethylene chlorotrifluoroethylene copolymer, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, perfluorocyclopolymer, vinyl ether fluoroolefin copolymer, vinyl ester fluoroolefin Copolymer, tetrafluoroethylene vinyl ether copolymer, chlorotrifluoroethylene vinyl ether copolymer, tetrafluoroethylene urethane crosslinked product, tetrafluoroethylene epoxy crosslinked product, tetrafluoroethylene acrylic crosslinked product, tetrafluoroethylene melamine Made of crosslinked material and mixtures thereof It is selected from the group true is preferred.

According to another embodiment of the present invention, in the conductive polymer composition, the alcohol solvent is preferably used by selecting one or more of aliphatic alcohols having 1 to 5 carbon atoms.

According to another embodiment of the present invention, in the conductive polymer composition, the functional organic solvent is dimethyl sulfoxide, propylene glycol methyl ether, N-methylpyrrolidone, ethyl-3-ethoxypropionate, propylene glycol monomethyl It is preferably selected from the group consisting of ether acetate, butyl carbitol and mixtures thereof.

In addition, according to another embodiment of the present invention, in the method for producing a conductive polymer coating film, the conductive polymer coating composition may be further diluted with a mixed solvent of water and alcohol.

Using the conductive polymer coating composition of the present invention, it is possible to simply and conveniently prepare a conductive polymer coating film excellent in both antistatic, pollution control performance and printability.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

As described above, the conductive polymer coating composition of the present invention comprises a conductive polymer aqueous dispersion containing a polythiophene-based, polypyrrole-based, polyaniline-based polymer compound or a mixture thereof; Water-soluble binder resins; Alcohol solvents; Functional organic solvents; water; Water-soluble olefin waxes; And fluorine-based resins.

The conductive polymer used in the conductive polymer coating composition of the present invention has an antistatic effect on the surface of the coating film and is used to remove contaminants such as dust. The conductive polymer aqueous dispersion in the conductive polymer coating composition of the present invention is a dispersion or dissolution of the conductive polymer compound in water, and the concentration of the polymer compound is 0.1 to 10% by weight based on the total dispersion. The conductive high molecular compound is preferably a polythiophene-based, polypyrrole-based, polyaniline-based high molecular compound or a mixture thereof, more preferably a double polythiophene-based compound, and particularly preferably polyethylenedioxythiophene (PEDOT).

Meanwhile, Bayer P or Baytron PH, which are commercially available as Bayer, may be used as the aqueous dispersion. Baytron P is a product in which polystyrenesulfonic acid (PSS) is added as a dopant to an aqueous dispersion in which polyethylendioxithiophene (PEDOT) is dispersed in water. The content of polyethylenedioxythiophene in the Baytron P is about 1.4%.

The content of the conductive polymer aqueous dispersion is preferably 1 to 30% by weight based on the total conductive polymer coating composition. If the content of the conductive polymer aqueous solution is less than 1% by weight, the surface resistance is increased, there is a problem that the antistatic and electromagnetic shielding performance of the coating film after coating is lowered, if it exceeds 30% by weight without increasing the antistatic function There is a problem that the coating property is lowered.

The water-soluble binder resin used in the conductive polymer coating composition of the present invention improves the dispersibility of the conductive polymer, and serves to improve film uniformity, adhesion, film strength, etc. of the resulting coating film. As the water-soluble binder resin used in the present invention, polyurethane, polymethyl methacrylate, polyacrylate, polyvinyl alcohol, polyvinyl acetal, polyvinylacetate or a mixture thereof is preferable, and water-soluble polyurethane resin is particularly preferable. .

The content of the water-soluble binder resin is preferably 5 to 25% by weight based on the total conductive polymer coating composition. If the content of the water-soluble binder resin is less than 5% by weight, there is a problem that the uniformity, adhesion and film strength of the coating film is lowered, and when the content of the water-soluble binder resin is greater than 25% by weight, the dispersibility of the conductive polymer is lowered.

It is preferable that the conductive polymer coating composition according to the present invention contains 5 to 40% by weight of an alcohol solvent based on the total conductive polymer coating composition. The alcohol solvent serves to improve the coating property such as drying properties of the coating composition. As the alcohol solvent, an alcohol compound commonly used in the conductive polymer coating composition may be widely used, and preferably, any one or more of aliphatic alcohols having 1 to 5 carbon atoms may be selected, and more preferably methanol, Ethanol, isopropyl alcohol (IPA) or a mixture thereof may be used, and preferably, a solvent mixture prepared by mixing ethanol and isopropyl alcohol may be used.

If the content of the alcohol solvent is less than 5% by weight relative to the total conductive polymer coating composition, there is a concern that the drying property is lowered. If the content of the alcohol solvent exceeds 40% by weight, the dispersibility of the conductive polymer is lowered to increase the surface resistance.

The conductive polymer coating composition according to the present invention may further include a functional organic solvent which improves coating properties such as solubility, dispersibility, drying property, film uniformity, etc. of the coating composition together with the alcohol solvent. The functional organic solvents include dimethyl sulfoxide (DMSO), propyleneglycol methylether (PGME), N-methylpyrrolidone (NMP), ethyl-3-ethoxypropionate (ethyl-3- ethoxypropionate; EEP), propyleneglycol monomethyl etheracetate (PGMEA), butyl carbitol (BC) or mixtures thereof, and preferably dimethyl sulfoxide do.

The content of the functional organic solvent is 5 to 30% by weight, preferably 10 to 30% by weight based on the total conductive polymer coating composition. When the content of the functional organic solvent is less than 5% by weight, there is a problem in that the coating composition of the coating composition is inferior and a non-uniform film is formed, and when the content of the functional organic solvent exceeds 30% by weight, there is a problem in that the drying property is not improved without particularly improving the coating performance.

As the water-soluble olefin wax used in the conductive polymer coating composition according to the present invention, a polyolefin wax showing ink printability and paint adhesion is used. As the polyolefin wax, ethylene wax and propylene wax may be used alone or in combination.

The content of the water-soluble olefin wax is preferably used in an amount of 0.1 to 10% by weight based on the total ink composition. When the content of the water-soluble olefinic wax is less than 0.1% by weight, the printability is reduced, so that it is difficult to display by oily ink. When the content of the water-soluble olefinic wax is more than 10% by weight, the antistatic function is lowered, and the stability of the coating solution is also reduced, resulting in gelation.

The fluorine resin used in the conductive polymer coating composition according to the present invention improves the adhesion between the substrate and the coating film. Examples of the fluorine-based resins include polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polychlorotrifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, and ethylene tetrafluoroethylene copolymer. , Ethylenechlorotrifluoroethylene copolymer, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, perfluorocyclopolymer, vinyl ether fluorool lepin copolymer, vinyl ester fluoroolefin copolymer, tetrafluoroethylene Contains fluoro groups such as vinyl ether copolymer, chlorotrifluoroethylene vinyl ether copolymer, tetrafluoroethylene urethane crosslinked product, tetrafluoroethylene epoxy crosslinked product, tetrafluoroethylene acrylic crosslinked product and tetrafluoroethylene melamine crosslinked product A polymer may be suitably used. Polytetrafluoroethylene (PTFE) is preferable at the point which has high adhesiveness among the said fluororesin.

The content of the fluorine-based resin is preferably 0.001% to 5% by weight based on the total conductive polymer coating composition. When the content of the fluorine-based resin is less than 0.001%, the surface contact angle with respect to water decreases to reduce the stain resistance, and if the content of the fluorine-based resin exceeds 5 wt%, the stain resistance increases to affect printability, thereby making it difficult to display by ink.

Next, the manufacturing method of the conductive polymer coating composition of this invention is demonstrated.

The above components of content are mixed and uniformed to form a conductive polymer coating composition. When mixing, water is added to disperse the water-soluble binder and the conductive polymer aqueous dispersion. Water is preferably 10 to 50% by weight based on the total conductive polymer coating composition.

Hereinafter, a manufacturing method of the conductive polymer coating film will be described.

Method for producing a conductive polymer coating film according to the present invention, the step of coating the conductive polymer coating composition according to the invention on a substrate; And drying the coated composition.

In the method for producing a conductive polymer coating film of the present invention, the coating may be optionally performed using a coating solution further diluted with the conductive polymer coating composition with a mixed solution of water and ethanol. Preferably, the conductive polymer coating composition: water: ethanol is diluted in a ratio of 1: 1: 3.

As a base material for coating the coating composition, an organic polymer base material such as polyester, polystyrene, polyimide, polyamide, polysulfonate, polycarbonate, polyacrylate, polyethylene, and polypropylene is coated.

Preferred coating methods include gravure coating, reverse coating and roll coating.

Drying conditions of the coating film is selected for the appropriate coating method, but it is preferably carried out for 5 to 120 seconds at a temperature of 60 to 120 ℃ commonly used, at a temperature of 80 to 120 ℃, 10 to More preferably, it is carried out for 100 seconds. Especially preferably it is dried for 1 minute at the temperature conditions of 80 degreeC after coating.

When the drying and curing temperatures are less than 60 ° C., the drying is insufficient. When the drying and curing temperature is higher than 120 ° C., there is no advantage in terms of the performance of the coating film compared to when drying and curing at 120 ° C. or lower, and the cost is high and the operational risk due to high temperature heating is increased. there is a problem.

If the drying and curing time is less than 5 seconds, the drying is insufficient, and even if dried and cured for more than 120 seconds, there is no advantage in terms of performance of the coating film, and the cost of forming the coating film is high.

The antistatic property of the conductive polymer coating film thus obtained is preferably controlled to a surface resistance of 1 × ^{10 10} Pa / □ or less. If the surface resistance is larger than 1ⅹ10 ¹⁰ Ω / □, dust cannot be prevented in the process of removing the protective film by peeling, thereby preventing the occurrence of static electricity. In addition, when the protective film is applied to the liquid crystal display, there arises a problem that the liquid crystal display element is destroyed by the peeling charge generated in the process of peeling the protective film.

The contact angle of the conductive polymer coating film is preferably 80 ° or more, more preferably 90 ° or more. If the contact angle is less than 80 °, the liquid crystal display cannot be protected from various contaminants generated during the operation.

Conductive polymer coating film according to the production method of the present invention is preferably ink wettability of 0.75 or more. If the ink wettability is less than 0.75, the printed ink does not spread well, which is undesirable. On the other hand, in the printing adhesiveness of the coating film, when the scotch tape is attached to the printed coating film and peeled off at 45 ° angle, there should be almost no dropout of the printed portion.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following examples and comparative examples, percentages and mixing ratios are by weight unless otherwise indicated.

(Comparative Example 1)

Preparation of Coating Composition and Coating Film (Antistatic Layer)

20 parts by weight of water, 20 parts by weight of dimethyl sulfoxide, 10 parts by weight of ethanol and 15 parts by weight of isopropyl alcohol were added to the mixing vessel, followed by stirring for 1 hour. 15 parts by weight of a water-soluble polyurethane resin was added thereto and further stirred for 1 hour. Then, 20 parts by weight of an aqueous polyethylenedioxythiophene (PEDOT) dispersion was added and stirred for 1 hour to prepare a coating composition. As the aqueous polyethylenedioxythiophene dispersion, Baytron P (PEDOT concentration 1.4 wt%) manufactured by Bayer, doped with polystyrene sulfonate, was used. The resulting coating composition was further diluted with a mixed solvent of pure water and ethanol to prepare a final coating solution (coating solution: water: ethanol weight ratio = 1: 1: 3). The PET film was coated with the final coating solution using a bar coater, and dried for 1 minute on a hot plate at 80 ° C. to obtain a coating film.

(Comparative Example 2)

Coating Film (Antistatic Layer / Antifouling layer Manufacturing

The coating film coated with the same composition as in Comparative Example 1, a fluorine-based resin diluted to 20% by weight in toluene solvent, coated once more using a bar coater, dried for 1 minute on an 80 ° C hot plate and then coated twice One coating film was obtained.

(Comparative Example 3)

Preparation of Coating Composition and Coating Film

In the coating composition of Comparative Example 1, 0.5 parts by weight of the fluorine-based resin diluted to 20% by weight in toluene solvent was added to the total coating composition and stirred for 1 hour. The resulting coating composition was further diluted with a mixed solvent of water and ethanol to prepare a final coating solution (coating solution: water: ethanol weight ratio = 1: 1: 3). The PET film was coated with the final coating solution using a bar coater, and dried on a hot plate at 80 ° C. for 1 minute to obtain a coating film.

(Examples 1 and 2)

Preparation of conductive polymer coating composition and coating film

A coating composition was prepared in the same composition as in Comparative Example 1, but additional 0.5 parts by weight of an additive was added as shown in Table 1, followed by stirring for 1 hour. The resulting coating composition was further diluted with a mixed solvent of water and ethanol to prepare a final coating solution (coating solution: water: ethanol = 1: 1: 3). The PET film was coated with the final coating solution using a bar coater, and dried on a hot plate at 80 ° C. for 1 minute to obtain a coating film.

Composition of the Coating Composition Fluorine Resin (PTFE) Polyolefin Wax (PE) Number of coatings Solvent system (toluene) water system water system Comparative Example 1 - - - 1 time Comparative Example 2 0.5wt% - Episode 2 Comparative Example 3 0.5wt% - - 1 time Example 1 - 0.2wt% 0.3wt% 1 time Example 2 0.3wt% 0.2wt% 1 time

Measurement of Properties of Coating Film

Surface resistance, contact angle, ink wettability, print adhesiveness, and transmittance were measured using the coating films prepared in Comparative Examples 1 to 3 and Examples 1 and 2, and the measurement results are shown in Table 2 below.

(1) surface resistance

Surface resistance was measured using a ST-3 measuring instrument from SIMCO.

(2) contact angle

The contact angle was measured using DSA 100 from KRUSS.

(3) ink wettability

Ink wettability is measured by the ratio of the ink dot size printed to the coating film sample with respect to the dot size of the organic ink which printed the corona-treated biaxially stretched polyester on the film, and is calculated by the following formula.

Ink wettability = size of dots printed on coating film sample / size of dots printed on axial stretch polyester film

(4) printing adhesive

Print adhesiveness was evaluated as follows according to the degree of the printed portion adhered to the printed film, and then peeled off at a 45 degree angle and buried on the tape surface.

(Double-circle): Almost no fall of a printing part;

(Triangle | delta): The fall of the printing part is partial;

X: Almost all the printing parts fall out.

(5) transmittance

The transmittance was measured by measuring the film transmittance before coating and the film transmittance after coating was expressed as the difference.

Evaluation of Properties of Coating Film Coated Film Coating composition state Properties of Coating Film Immediately after preparation of the coating composition After 24 hours Surface resistance (Ω / □) Contact angle (degrees) Ink wettability Printing adhesive Transmittance (%) Comparative Example 1 Good Good 1ⅹ10 ⁶ 70 1.00 ◎ 99 Comparative Example 2 Good Good 1ⅹ10 ⁶ 97 0.90 ◎ 99 Comparative Example 3 Good Gelation 1ⅹ10 ⁶ 102 0.72 × 99 Example 1 Good Good 1ⅹ10 ⁶ 95 0.90 ◎ 99 Example 2 Good Good 1ⅹ10 ⁶ 96 0.90 ◎ 99

In Comparative Example 1 in which only the antistatic layer was formed, the antistatic performance and other physical properties were the best, but the contact angle of the water was low, so that the contamination by the pollutant was high. In the case of Comparative Example 2, which is widely used at present, the process cost is high by performing the antistatic layer forming process and the antifouling layer forming process twice. The coating composition of Comparative Example 3 can be used immediately after preparation as a coating composition incorporating Comparative Examples 1 and 2, but after 24 hours of manufacture, the coating composition is gelled and is not suitable for use in actual coating film manufacturing process. .

In Examples 1 and 2, excellent antistatic performance, a contact angle of 90 ° or more, and an ink wettability of 0.8 or more were observed, and there was almost no dropout of the printing portion, and an excellent transmittance was maintained. That is, by using a one-component conductive polymer coating composition containing additives that impart both pollution control performance and printability, a conductive polymer coating film having excellent antistatic property, ink wettability and adhesiveness, etc. is produced with only one coating operation. Could. The coating film is suitable for use as a surface protection film to protect the surface of the display device, which is gradually increasing in size.

Using the conductive polymer coating composition of the present invention as described above, it is possible to simply and conveniently prepare a conductive polymer coating film excellent in both antistatic, pollution control performance and printability. The conductive polymer coating composition of the present invention can reduce the cost and time in the manufacturing process of the surface protection film in one component. In addition, the conductive polymer coating composition of the present invention is environmentally friendly using a water-soluble solvent. The conductive polymer coating film obtained by the manufacturing method according to the present invention has suitable coating properties and optical properties as a protective film of a display such as an LCD.

Claims (11)

In the conductive polymer coating composition for the protective film, 1 to 30% by weight of a conductive polymer aqueous dispersion containing polythiophene, polypyrrole, polyaniline-based polymer compound or a mixture thereof; 5 to 25% by weight of the water-soluble binder resin; Alcohol solvent 5-40% by weight; 5 to 30 weight percent functional organic solvent 10 to 50 weight percent; water; 0.1 to 10% by weight of water-soluble olefin wax; And 0.001 to 5% of a fluorine-based resin. The conductive polymer coating composition of claim 1, wherein the conductive polymer aqueous dispersion comprises polyethylenedioxythiophene (PEDOT). The conductive binder of claim 1, wherein the water-soluble binder resin is selected from the group consisting of polyurethane, polymethylmethacrylate, polyacrylate, polyvinyl alcohol, polyvinyl acetal, polyvinylacetate, and mixtures thereof. Polymer coating composition. The conductive high molecular weight coating composition of claim 1, wherein the water-soluble olefin wax is selected from the group consisting of ethylene wax, propylene wax, and mixtures thereof. The method of claim 1, wherein the fluorine-based resin is polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polychlorotrifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, ethylene tetrafluoroethylene copolymer , Ethylenechlorotrifluoroethylene copolymer, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, perfluorocyclopolymer, vinyl ether fluoroolefin copolymer, vinyl ester fluoroolefin copolymer, tetrafluoroethylene vinyl Ether copolymer, chlorotrifluoroethylene vinyl ether copolymer, tetrafluoroethylene urethane crosslinked product, tetrafluoroethylene epoxy crosslinked product, tetrafluoroethylene acrylic crosslinked product, tetrafluoroethylene melamine crosslinked product and mixture thereof All characterized in that the selected from Polymer coating composition. The conductive polymer coating composition of claim 1, wherein the alcohol solvent is an aliphatic alcohol having 1 to 5 carbon atoms. The conductive polymer coating composition of claim 4, wherein the alcohol solvent is methanol, ethanol, isopropyl alcohol, or a mixture thereof. The method of claim 1, wherein the functional organic solvent is dimethyl sulfoxide, propylene glycol ether, N-methylpyrrolidone, ethyl-3-ethoxypropionate, propylene glycol monomethyl ether acetate, butyl carbitol and these A conductive polymer coating composition, characterized in that selected from the group consisting of. Coating the conductive polymer coating composition of claim 1 on a substrate; And Method for producing a conductive polymer coating film comprising the step of drying the coated composition. 10. The method of claim 9, wherein the conductive polymer coating composition is further diluted with a mixed solvent of water and alcohol. A conductive polymer coating film prepared according to claim 9 or 10.