KR20130001463A - Anti-static coating composition having diverse anti-static level and anti-static polyester film using the same - Google Patents

Abstract

PURPOSE: An anti-static coating composition is provided to obtain various surface resistances according to the content of a conductive polymer resin and to provide a polyester film with excellent transparency and antistatic performance. CONSTITUTION: An anti-static coating composition comprises: 100 parts by weight of a water-dispersible polyurethane resin which consists of a polyether polyurethane dispersion of anions comprising functional groups selected from a hydroxy group, an amine group, an alkyl group and a carboxy group; 50-1000 parts by weight of a crosslinking resin selected from isocyanate, carbonylimide, oxazoline, epoxy and melamine based resins; 1-100 parts by weight of a fluorine resin, 0.1-100 parts by weight of an acetylene diol-based surfactant, and 1-100 parts by weight of a conductive polymer resin. The surface resistance value is controlled within 10^5-10^10 ohm/sq according to the content of the conductive polymer resin. [Reference numerals] (AA) Surface resistance; (BB) PEDOT weight part

Description

Antistatic coating composition which realizes various antistatic performance and antistatic polyester film using same {ANTI-STATIC COATING COMPOSITION HAVING DIVERSE ANTI-STATIC LEVEL AND ANTI-STATIC POLYESTER FILM USING THE SAME}

The present invention relates to an antistatic coating composition which realizes various antistatic properties and to an antistatic polyester film using the same, and more particularly, to contain a polyurethane resin to improve peel strength with an adhesive tape and at the same time contain a crosslinker resin. To improve solvent resistance and coating performance by controlling crosslinking density, to improve antifouling performance by containing fluorine resin, and to contain acetylene diol-based surfactants to minimize coating appearance defects, and in particular, depending on the content of conductive polymer resin. The present invention relates to an antistatic coating composition capable of implementing antistatic performance and an antistatic polyester film using the same.

With the development of industrialization and the damage caused by the generation of static electricity in many fields such as various electronic and electric devices, information and communication fields, and general household goods, the need for antistatic in the related fields is increasing day by day.

Problems caused by static electricity in the industrial field include impurities or dust attached to the static electricity generated in the product and discharge in the film manufacturing process or the film processing process. Increases.

In addition, when static electricity is generated in materials such as electric and electronic parts, it is a major cause of product damage, and therefore, it is essential to provide antistatic performance in electric and electronic fields.

Antistatic means discharging the charge accumulated on the surface of the insulator in an appropriate manner. To implement the antistatic, an antistatic layer is formed on the surface of the product to discharge the accumulated charge on the surface.

Known antistatic techniques, including the formation of the antistatic layer, include internal addition using an anionic compound such as organic sulfonate and organic phosphate, a method of depositing a metal compound on the surface, a method of applying conductive inorganic particles, a low molecular type anionic Or a method of applying a cationic compound and a method of applying a conductive polymer.

Among the above methods, the internal addition method is inexpensive, and has the advantage of excellent change over time and stability, but the disadvantage of inhibiting the inherent properties of the film support, the limitation of the antistatic effect, between the film and the laminate due to blooming There are problems such as deterioration of adhesion, and the method of depositing a metal compound on the surface is excellent in antistatic property and has been widely used for conductive films in recent years, but the manufacturing cost is so high that it is used only for specific applications.

In addition, the coating method using a low molecular type anionic or cationic compound has been widely applied because of the relatively good antistatic effect and advantageous in terms of manufacturing cost, but due to the characteristics of antistatic properties combined with moisture in the air In the case where the water content is low, the antistatic property is greatly lowered, the solvent resistance is poor, and the application is greatly limited because of the disadvantages of the possibility of transferring to the other side.

Accordingly, in order to overcome the above problems, recently, polyaniline, polypyrrole, or polythiophene conductive polymers which are dissolved in water and an organic solvent have been developed, thereby providing conductivity to an antistatic polyester film or other polymer surface. Many researches are in progress.

Among the known methods for antistatic, a method generally used is a method of preparing a conductive polymer that is doped, and then dissolving it in a suitable solvent to coat various polymer surfaces including polyester.

For example, US Pat. No. 4,959,430 discloses 3,4-ethylenedioxythiophene, a kind of conductive polymer monomer, and ferrictoluene sulfonate (Iron (III) p-toluenesulfonate) as an oxidizing agent at room temperature. A 3,4-polyethylenedioxythiophene polymer having excellent conductivity synthesized by mixing is disclosed. The synthesized 3,4-polyethylenedioxythiophene polymer may be commercially available in the form of being dispersed in water. When the mixture is left at room temperature for a long time by mixing 3,4-ethylenedioxythiophene and ferrictoluenesulfonate, the polymerization reaction is performed. To prevent this, a small amount of imidazole, a reaction inhibitor, may be mixed to prevent this.

In addition, Japanese Patent Laid-Open No. Hei 1-313521 discloses an electrically conductive polymer composed of poly (3,4-diaalkoxythiophene) and poly anion, and has a high electrical conductivity, high chemical stability, and a coating film during film formation. It is attracting attention as having a high transparency. However, when the coating liquid containing the electrically conductive polymer is applied to a plastic substrate, it is not easy to obtain a coating film that satisfies all the performances of adhesion, transparency, water resistance, solvent resistance and electrical conductivity to the substrate at the same time.

In particular, the conventional conductive polymer resin is easy to implement a surface resistance value of 10 ⁵ ~ 10 ⁶ Ω / sq, but difficult to obtain a surface resistance value of 10 ⁸ ~ ^{10 10} Ω / sq.

Therefore, in order to improve the water resistance of the coating film, a method of crosslinking the resin with a crosslinking agent has been attempted. In Japanese Patent Laid-Open No. 6-73271, poly (3,4-dialcoholthiophene) and polyanion are used. Although an alkoxysilane compound having an epoxy group has been used for the purpose of improving the adhesion between the electrically conductive polymer layer and the layer adjacent thereto, it is still insufficient to impart water resistance to the coating film.

With the recent growth of the IT industry including the liquid crystal display (hereinafter referred to as LCD) and plasma display panel (hereinafter referred to as PDP) markets, the demand for antistatic films is rapidly increasing. As an antistatic technology applied to electronic applications, it is common to use a cationic antistatic technology, and an antistatic technology using a conductive polymer is entering the advanced film market.

Therefore, in the industrial field requiring the antistatic performance, there is an urgent need for an antistatic film having excellent antistatic performance and improved adhesion with adhesive tape, adhesion with ink, and antifouling performance.

Accordingly, the present inventors have made an effort to solve the above-described problems, and as a result, the peeling force between the acrylate-based commercial tape having high transparency and antistatic property and the relatively low adhesive paper commercial tape All have excellent physical properties, antifouling performance is improved, in particular, by providing an antistatic coating composition capable of implementing a variety of antistatic performance according to the content of the conductive polymer resin, the present invention was completed.

It is an object of the present invention to provide an antistatic coating composition capable of realizing various surface resistances in the range of 10 ⁵ to ^{10 10} Ω / sq depending on the conductive polymer resin content.

Another object of the present invention is to apply the antistatic coating composition in an in-line coating method, excellent transparency and antistatic properties, but also excellent peeling strength, antifouling performance and coating properties with the adhesive tape, in particular, easy to control the physical properties to change the market It is to provide an antistatic polyester film that can respond quickly to the requirements according to.

In order to achieve the above object, the present invention is an antistatic coating composition for satisfying the optimum physical properties, an anionic polyether containing at least one functional group selected from the group consisting of hydroxyl groups, amine groups, alkyl groups and carboxyl groups 50 to 1000 parts by weight of any one crosslinking agent resin selected from the group consisting of isocyanate, carbonylimide, oxazoline, epoxy and melamine based on 100 parts by weight of the water-dispersible polyurethane resin composed of the polyurethane dispersion, 1 to 100 parts by weight of the fluororesin, 0.1 to 100 parts by weight of the acetylene diol-based surfactant and 1 to 100 parts by weight of the conductive polymer resin, and the surface resistance value within the range of 10 ⁵ ~ ^{10 10} Ω / sq depending on the content of the conductive polymer resin It provides an antistatic coating composition, characterized in that controlled in.

At this time, the conductive polymer resin used in the present invention is a water dispersion containing poly anion and polythiophene or a water dispersion containing poly anion and polythiophene derivative, 1 to 5% by weight of poly anion in the water dispersion It is preferred that the water dispersion contains at least 1 to 40% by weight of polythiophene or polythiophene derivative.

In addition, the fluororesin used in the antistatic coating composition of the present invention is tetrafluoroethylene copolymer, trifluoroethylene copolymer, hexafluoropropylene copolymer, chlorotrifluoroethylene-tetrafluoroethylene copolymer, chloro At least one selected from the group consisting of trifluoroethylene-polytetrafluoroethylene copolymer, polyvinyl fluoride and polyvinylidene fluoride is used.

The acetylene diol-based surfactant can improve the coating property without deteriorating the physical properties, wherein the acetylene diol-based surfactant is a compound represented by the following formula (1).

(Wherein R ₁ and R ₄ are C ₃ to C ₁₀ linear or pulverized alkyl group, halogen substituted alkyl group, vinyl group, allyl group, ethynyl group, phenyl group, aryl group, halogen group, C _{3 to} C ₁₀ Is selected from an alkoxy group, cyano group, amino group, hydroxyl group, carbonyl group, ester group or carboxyl group, R ₂ , R ₃ are H or C ₁ -C ₅ alkyl group, m, n, p, q are 0-20 Is an integer.)

At this time, the antistatic coating composition of the present invention is the content of the solid content contained in the composition is 0.5 to 10.0% by weight.

The present invention provides an antistatic polyester film having an antistatic layer formed on one side or both sides of a polyester film by applying the antistatic coating composition.

The antistatic polyester film has a surface resistance value of less than 1 × 10 ¹⁰ Pa / sq before and after the film surface is cleaned with any one organic solvent selected from the group consisting of ethanol, methyl ethyl ketone, toluene and ethyl acetate. Prevention is secured.

In addition, the antistatic polyester film satisfies the peeling force with the acrylate-based tape (NITTO # 31B) more than 1,000g / in and the peeling force with the paper-based tape (3M # 244) 150g / 18mm or more, The water contact angle of the preventive polyester film is 90 or more, so it has excellent antifouling function.

Furthermore, the present invention provides a surface protection film for an optical display device using an antistatic polyester film whose antistatic performance is controlled by the 10 ⁵ to ^{10 10} Ω / sq surface resistance.

By providing the antistatic coating composition of the present invention, the polyurethane resin is contained to improve the peeling force with the adhesive tape and the crosslinking density is adjusted using an appropriate crosslinking agent to improve solvent resistance and coating performance, and to add fluorine resin. By improving the antifouling performance, and by containing an acetylene diol-based surfactant, it is easy to control the coating properties because there is little change in the physical properties according to the content while minimizing the coating appearance defects. In particular, according to the content control of the conductive polymer resin, it is possible to implement a variety of surface resistance up to ^{10 5} ~ ^{10 10} Ω / sq.

Furthermore, by applying the antistatic coating composition of the present invention to one or both sides of the polyester film, while excellent in transparency and antistatic properties, peeling force and antifouling performance with the adhesive tape is improved, in particular, 10 ^{5-10 10} Ω By implementing various antistatic performance within / sq range, it is possible to provide an antistatic polyester film that can respond quickly to the requirements of the market changes.

Thus, the antistatic polyester film of the present invention is applied to various applications because the antistatic performance is controlled up to 10 ⁵ ~ ^{10 10} Ω / sq surface resistance, liquid crystal display, plasma display, organic light emitting diode display, electronic paper display ( It is useful as a surface protection film in various displays, such as an E-Paper Display, an optical display device, such as a personal digital assistant and a navigation | navigation.

Figure 1 shows the change in the surface resistance value according to the content of the conductive polymer resin in the antistatic coating composition of the present invention.

Hereinafter, the present invention will be described in more detail.

The present invention is based on 100 parts by weight of a water-dispersible polyurethane resin composed of an anionic polyether polyurethane dispersion comprising at least one functional group selected from the group consisting of hydroxyl groups, amine groups, alkyl groups and carboxyl groups,

50 to 1000 parts by weight of any one crosslinker resin selected from the group consisting of isocyanate series, carbonylimide series, oxazoline series, epoxy series and melamine series,

1 to 100 parts by weight of a fluororesin,

0.1 to 100 parts by weight of an acetylene diol surfactant and

Containing 1 to 100 parts by weight of the conductive polymer resin,

It provides an antistatic coating composition characterized in that the surface resistance value is controlled within the range of 10 ⁵ ~ ^{10 10} Ω / sq depending on the conductive polymer resin content.

Hereinafter, each composition of the antistatic coating composition of the present invention will be described.

In describing the polyurethane resin contained in the antistatic coating composition of the present invention, the polyurethane resin used in the present invention is applied to a polyester film and added to increase the peeling force between the film surface and the tape.

Accordingly, a preferred polyurethane resin used in the present invention is a water dispersion type, and a resin composed of an anionic polyether polyurethane dispersion containing at least one or more functional groups such as hydroxyl groups, amine groups, alkyl groups and carboxyl groups is used. .

More specifically, the water-dispersible polyurethane resin may include a polyether polyurethane dispersion of an anion including a hydroxyl group; Functional groups of repeating units selected from the group consisting of allylamine, vinylamine, ethyleneamine, vinyl pyridine, diethylaminoethyl methacrylate, diallyldimethylammonium chloride, methacryloyloxyethyltrimethylammonium sulfate and combinations thereof Polyether polyurethane dispersion of the anion containing; Or polyether polyurethane dispersions of anions comprising functional groups of repeating units selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl and combinations thereof.

Referring to the crosslinking agent contained in the antistatic coating composition of the present invention, the crosslinking agent used in the present invention is used to improve the solvent resistance and coating film performance of the antistatic layer and the polyester film by controlling the crosslinking density. At this time, any one or more resins selected from the group consisting of isocyanate type, carbonylimide type, oxazoline type, epoxy type and melamine type can be used as the preferred crosslinking agent component.

In addition, the quantity of the crosslinking agent added can add 50-1,000 weight part of crosslinking agent resin with respect to 100 weight part of polyurethane resins. At this time, when the amount of the crosslinking agent resin added is less than 50 parts by weight, the antistatic property is weak, the solvent resistance is weak and whitening may occur. On the other hand, if it exceeds 1,000 parts by weight, a problem may occur that the transparency is good but the antistatic property becomes difficult to be expressed.

Of the antistatic coating compositions, the fluorine resin added to the present invention is added to the polyester film to improve the antifouling property and solvent resistance of the film.

Preferred fluororesins include tetrafluoroethylene copolymer, trifluoroethylene copolymer, hexafluoropropylene copolymer, chlorotrifluoroethylene-tetrafluoroethylene copolymer, chlorotrifluoroethylene-polytetrafluoroethylene At least one selected from the group consisting of copolymers, polyvinyl fluorides and polyvinylidene fluorides is used.

At this time, 1-100 weight part of fluororesins can be added with respect to the quantity of the fluororesin added. If the addition amount of the fluorine resin is less than 1 part by weight, the antifouling property is lowered, whereas if it is more than 100 parts by weight, there may be a problem that the transparency, tape peeling force and antistatic performance of the film is lowered.

The antistatic coating composition of the present invention adds a surfactant to improve the stability, wetting and application leveling of the coating composition. The surfactant may be used at least one selected from the group consisting of anionic, cationic, nonionic and zwitterionic, acetylene diol-based surfactant is most preferred. This is because the acetylene diol-based surfactant can solve the conventional problems by maintaining the main coating properties such as peel strength with the adhesive tape, antifouling properties while improving the wettability, coating leveling properties of the coating composition.

That is, the acetylene diol-based surfactant of the present invention is characterized in that the compound represented by the following formula (1).

Formula 1

(Wherein R ₁ and R ₄ are C ₃ to C ₁₀ linear or pulverized alkyl group, halogen substituted alkyl group, vinyl group, allyl group, ethynyl group, phenyl group, aryl group, halogen group, C _{3 to} C ₁₀ Is selected from an alkoxy group, cyano group, amino group, hydroxyl group, carbonyl group, ester group or carboxyl group, R ₂ , R ₃ are H or C ₁ -C ₅ alkyl group, m, n, p, q are 0-20 Is an integer.)

At this time, the preferable content of the acetylene diol-based surfactant is to add 0.1 to 100 parts by weight based on 100 parts by weight of the polyurethane resin. If the amount of surfactant added is less than 0.1 part by weight, the wettability of the coating film is lowered, and if it is more than 100 parts by weight, fine bubbles in the coating composition cause coating appearance defects.

The conductive polymer resin contained in the antistatic coating composition of the present invention is used to impart excellent antistatic performance, and preferably contains an aqueous dispersion containing polyanion and polythiophene or a polyanion and polythiophene derivative. Use water dispersion. At this time, the polyanion is contained in the water dispersion 1 to 5% by weight. In the above, the polyanion is an acidic polymer, and is a polymer carboxylic acid or a polymer sulfonic acid, a polyvinyl sulfonic acid, or the like. Examples of the polymer carboxylic acid include polyacrylic acid, polymethacrylic acid, polymaleic acid, and the like, and the polymer sulfonic acid includes polystyrene sulfonic acid.

In the conductive polymer resin of the present invention, it is preferable from the viewpoint of imparting conductivity to the polythiophene or polythiophene derivative that an excessive solid content weight ratio of polyanions is present. For example, when 1% by weight of polythiophene or polythiophene derivative is used, the polyanion is more than 1% by weight, preferably 50% by weight or less. More preferably used in the range of 1 to 40% by weight. Thus, the embodiment of the present invention uses, but is not limited to, an aqueous dispersion containing 0.5 wt% of poly (3,4-ethylenedioxythiophene) and 0.8 wt% of polystyrenesulfonic acid (molecular weight Mn = 150,000).

Thus, the antistatic coating composition of the present invention can control the antistatic performance of the film by adjusting the content of the conductive polymer resin. That is, Figure 1 shows a change in the surface resistance value according to the content of the conductive polymer resin in the antistatic coating composition of the present invention, the antistatic coating composition of the present invention is usually 10 ⁵ ~ 10 ⁶ Ω / sq can be implemented conductive polymer resin It is suggested that control is possible from the surface resistance region to 10 ⁵ to ^{10 10} Ω / sq surface resistance region.

More specifically, the red guff in FIG. 1 is a calibration curve (y = 10.12 × exp ^{(−x / 4.03)} + 5.62) calculated from the result of surface resistance (10 ^ y [Ω / sq]) according to the conductive polymer resin content. As the PEDOT weight part (x), the surface resistance (10 ^ y [Ω / sq]) value to be realized may be calculated or predicted.

On the other hand, the content of the conductive polymer resin added to the antistatic coating composition of the present invention is to add 1 to 100 parts by weight of the conductive polymer resin with respect to 100 parts by weight of the polyurethane resin. At this time, if the addition amount of the conductive polymer resin is less than 1 part by weight, the antistatic property is less likely to be expressed, and even if it exceeds 100 parts by weight, the antistatic performance is not greatly improved.

The antistatic coating composition of the present invention described above is preferably prepared so that the content of solids is 0.5 to 10.0 wt% with respect to 100 wt% of the total coating composition, and more preferably, the content of solids is 1.0 to 5.0 wt% To be manufactured. In this case, when the content of the solid content is less than 0.5% by weight, it is not sufficient to express the film formation and the antistatic performance of the coating layer, when it exceeds 10.0% by weight, it is not preferable because it affects the transparency of the film.

The antistatic coating composition of the present invention is an aqueous coating liquid using substantially water as the main medium as a solvent.

Thus, for the purpose of improving the coatability and transparency of the coating composition used in the present invention, a suitable organic solvent may be contained at a level that does not impair the effects of the present invention, and isopropyl alcohol is preferable. , Butyl cellosolve, t-butyl cellosolve, ethyl cellosolve, acetone, ethanol, methanol and the like can be used.

However, when a large amount of organic solvent is contained in the coating composition, when applied to the in-line coating method, there is a risk of explosion in the drying, stretching and heat treatment processes, so the content thereof is 10% by weight or less, more preferably 5% by weight in the coating composition. Control less than%.

The present invention provides an antistatic polyester film having an antistatic layer formed by applying the antistatic coating composition to one or both surfaces of a polyester film.

The antistatic coating composition used in the antistatic polyester film of the present invention is an aqueous coating liquid containing a crosslinking agent, a fluorine resin, an acetylene diol-based surfactant, and a conductive polymer resin as a solid content, as compared to the polyurethane resin, and its composition and content Since the same as the antistatic coating composition described above, a detailed description thereof will be omitted.

The antistatic polyester film of the present invention can optimize the desired physical properties, depending on the specific composition of the antistatic coating composition.

That is, it contains a conductive polymer to realize excellent antistatic performance, and a polyurethane resin to improve peeling force with the adhesive tape and an appropriate crosslinking agent to improve solvent resistance and coating performance by controlling crosslinking density, and By containing a resin to improve the antifouling performance, due to the addition of the acetylene diol-based surfactant, it is possible to prevent the coating properties from being lowered.

Therefore, the antistatic polyester film prepared by applying this to one or both sides of the polyester film is excellent in transparency and antistatic properties, easy to control coating defects, there is no degradation of physical properties due to the surfactant, in particular, the charging Due to the antistatic layer formed by applying the anti-coat coating composition, depending on the content of the conductive polymer resin, antistatic performance up to ^{10 5} ~ ^{10 10} Ω / sq surface resistance value can be applied to various applications.

In the antistatic polyester film of the present invention, the surface resistance is maintained at a value of less than 1 × 10 ¹⁰ dl / sq even before and after wiping the surface of the film with an organic solvent such as ethanol, methyl ethyl ketone, toluene, or ethyl acetate. In addition, the antistatic agent of the antistatic layer has excellent solvent resistance that does not drop or dissolve.

In addition, the antistatic polyester film of the present invention has an excellent antifouling performance because the water contact angle of the film exhibits 90 degrees or more, and the peeling force with the acrylate-based tape (NITTO # 31B) is 1,000 g / in or more, and the paper material Peeling force with the tape (3M # 244) at the same time meets more than 150g / 18mm. In other words, both the acrylate-based commercial tape used in the field and the peel strength of the commercial tape made of paper with relatively low adhesive strength meet both excellent physical properties, so that the antistatic polyester can respond quickly to the requirements of market changes. Films may be provided.

Accordingly, the antistatic polyester film of the present invention is useful for various displays such as liquid crystal displays, plasma displays, organic light emitting diode displays, electronic paper displays, and the like for optical display devices such as personal digital assistants and navigation devices. Can be applied. Further, in the future, it is possible to provide a polyester film that satisfies the demanding level of physical properties required for the enlargement of a display screen.

Furthermore, the antistatic polyester film of the present invention

1) uniaxially stretching the polyester film;

2) forming an antistatic layer by applying the antistatic coating composition of the present invention on one or both sides of the uniaxially stretched polyester film; And

3) A biaxially stretched polyester is produced by re-stretching the polyester film on which the antistatic layer is formed, and is produced by an in-line method.

That is, while the present invention is carried out in the in-line coating method, to improve the coating properties by controlling the viscosity and surface tension of the coating composition solution, the antistatic polyester film easy to control the coating properties such as antistatic properties, antifouling properties, peeling force Can provide.

In addition, by controlling the content of the conductive polymer resin in the coating composition, it is possible to implement a variety of antistatic performance, it is possible to provide a polyester film that can also be used for large-scale display applications.

The thickness of the biaxially stretched polyester film produced from the production method of the present invention is 5 to 300 µm, preferably 10 to 250 µm.

Hereinafter, the present invention will be described in more detail with reference to Examples.

This embodiment is intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

≪ Example 1 >

Step 1: Production of uniaxially stretched polyester film

A polyethylene terephthalate pellet having an intrinsic viscosity of 0.625 dl / g containing 20 ppm of amorphous spherical silica particles having an average particle diameter of 2.5 μm was thoroughly dried at 160 ° C. for 7 hours by using a vacuum drier, - An amorphous undrawn sheet was made by adhering it to the cooling drum through a die by electrostatic application, and the amorphous undrawn sheet was heated again and stretched 3.5 times in the film advancing direction at 95 캜 to prepare a uniaxially stretched polyester film. Thereafter, a corona discharge treatment was performed on the surface of the film to be coated to prepare a polyester film.

Step 2: Production of biaxially stretched polyester film

100 parts by weight of an epoxy crosslinking agent (Chemtech, GR-389) and a fluorine resin based on 100 parts by weight of the water dispersible polyurethane resin (anionic polyether polyurethane dispersion containing a hydroxy group) as a solid on the corona-treated surface. (Nanochem Co., AJ-32) 50 parts by weight, 0.1 part by weight of 2,5,8,11-tetramethyl 6dodecine-5,8 diol ethoxysilate as an acetylene diol-based surfactant and a conductive polymer resin (poly An antistatic coating solution was prepared by mixing 70 parts by weight of 0.5 wt% of 3,4-ethylenedioxythiophene and 0.8 wt% of polystyrenesulfonic acid (molecular weight Mn = 150,000). At this time, the content of the solid content was to contain 1.5% by weight relative to the total antistatic coating liquid.

The antistatic coating solution was applied to the uniaxially stretched polyester film prepared in Step 1 using a gravure roll. After coating, the coating liquid applied in the 105-140 ° C. tenter section was dried, stretched 3.5 times in the direction perpendicular to the traveling direction of the film, and heat-treated at 240 ° C. for 4 seconds to obtain a 38 μm-thick biaxially stretched antistatic polyester film. Prepared.

<Example 2>

Except for using an antistatic coating liquid containing 50 parts by weight of a conductive polymer resin (water dispersion containing 0.5% by weight of poly3,4-ethylenedioxythiophene and 0.8% by weight of polystyrenesulfonic acid (molecular weight Mn = 150,000)), A biaxially stretched antistatic polyester film was prepared in the same manner as in Example 1 above.

<Example 3>

Except for using an antistatic coating liquid containing 10 parts by weight of a conductive polymer resin (water dispersion containing 0.5% by weight of poly3,4-ethylenedioxythiophene and 0.8% by weight of polystyrenesulfonic acid (molecular weight Mn = 150,000)). In the same manner as in Example 1, a biaxially stretched antistatic polyester film was prepared.

<Example 4>

Except for using an antistatic coating liquid containing 7 parts by weight of a conductive polymer resin (an aqueous dispersion containing 0.5% by weight of poly3,4-ethylenedioxythiophene and 0.8% by weight of polystyrenesulfonic acid (molecular weight Mn = 150,000)). In the same manner as in Example 1, a biaxially stretched antistatic polyester film was prepared.

<Example 5>

Except for using an antistatic coating solution containing 3 parts by weight of a conductive polymer resin (an aqueous dispersion containing 0.5% by weight of poly3,4-ethylenedioxythiophene and 0.8% by weight of polystyrenesulfonic acid (molecular weight Mn = 150,000)). In the same manner as in Example 1, a biaxially stretched antistatic polyester film was prepared.

&Lt; Comparative Example 1 &

Except for using an antistatic coating liquid containing 130 parts by weight of a conductive polymer resin (an aqueous dispersion containing 0.5% by weight of poly3,4-ethylenedioxythiophene and 0.8% by weight of polystyrenesulfonic acid (molecular weight Mn = 150,000)), A biaxially stretched antistatic polyester film was prepared in the same manner as in Example 1 above.

Comparative Example 2

Except for using an antistatic coating solution containing 0.8 parts by weight of a conductive polymer resin (water dispersion containing 0.5% by weight of poly3,4-ethylenedioxythiophene and 0.8% by weight of polystyrenesulfonic acid (molecular weight Mn = 150,000)), A biaxially stretched antistatic polyester film was prepared in the same manner as in Example 1 above.

<Experimental Example>

About the antistatic polyester film manufactured in Examples 1-5 and Comparative Examples 1-2, the following physical property was evaluated and the result is shown in Table 1.

1. Water contact angle

Water contact angle was measured by the sessile drop method with purified water obtained by distilling ion-exchanged water using a contact angle measuring instrument (Kyowa Interface Science Co., Ltd .; model name Dropmaster 300), and measuring five times at different positions. After that, an average value was taken.

2. Antistatic property

The surface resistance was measured in accordance with JIS K7194 after the sample was installed in an environment of temperature 23 ° C. and humidity 50% RH using an antistatic measuring instrument (Mitsubishi Co., Ltd .; model name MCP-T600).

3. Ethanol Resistance

After ethanol was soaked in a cloth (BEMCOT), the coated film surface was reciprocated 10 times without load, and the state of the coated surface was evaluated based on the following criteria.

○: when the antistatic property is within the range of 10 ¹⁰ Ω / sq

Δ: change in antistatic property is more than 10 ¹⁰ Ω / sq and less than 10 ¹¹ Ω / sq

X: when antistatic property exceeds 10 ¹¹ Ω / sq

4. Peel force with tape-1

Acrylate adhesive tape (tape NO.31B made by Nitto Denko, width | variety) on the coating surface of the film obtained above using the peel force measuring device (AR1000 of a chemical equipment company) in 23 degrees +/- 3 degreeC, and 50 +/- 5% of relative humidity. : 25 mm), and then reciprocated once with a 2 kg load rubber roller, and pressed for 1 hour, followed by peeling 180 degrees at a peel rate of 0.3 MPM. The peeling force value obtained at this time was measured.

5. Peel force with tape-2

Paper adhesive tape (3M tape No. 244, width: 18 mm) was applied to the coated surface of the film obtained above using a peel force measuring instrument (AR1000 manufactured by Chemical Instruments) under 23 ° ± 3 ° C and 50 ± 5% relative humidity. After gluing, the rubber roller of 2kg load was reciprocated once and pressed, and after 1 hour, it was peeled 180 degrees at a peeling rate of 0.3 MPM. The peeling force value obtained at this time was measured.

6. Coating appearance

When the coated surface of the film obtained above was visually observed using various light sources such as fluorescent lamps, halogens and incandescent lamps, the size and number of uncoated parts were compared and evaluated according to the following criteria.

The area of the uncoated portion exceeded 1mm × 3mm and the inspection area was 1m ² .

◎: 0-1

○: 2-3

△: 4 to 10

×: more than 10

As can be seen from Table 1, in Comparative Example 1 containing 130 parts by weight of the conductive polymer in the composition of the antistatic coating solution, the antistatic performance and the peeling strength of the commercially available tape and acrylic commercial tape, Problems with more than 10 coating and coating appearance defects have been identified. Therefore, compared to the content of the high conductive polymer, it can not meet all the desired physical properties, it is uneconomical for cost.

In addition, in Comparative Example 2 in which the content of the conductive polymer in the composition of the antistatic coating solution was 1.0 parts by weight or less, the antistatic performance property was not expressed, and it was significantly lower in terms of peeling strength of the commercially available acrylic-based tape and the commercial tape. It was a shame.

On the other hand, it was possible to control the antistatic properties according to the conductive polymer content in the composition of the antistatic coating solution of the present invention. That is, according to the conductive polymer content in the composition of the antistatic coating solution, it is possible to control the antistatic performance up to 10 ⁵ ~ ^{10 10} Ω / sq.

In addition, the biaxially stretched antistatic polyester film prepared from the antistatic coating solution of Examples 1 to 5 of the present invention is transparent and has a surface resistance of less than 1 × 10 ⁸ dl / sq, and ethanol, methyl ethyl ketone, After the surface was cleaned with an organic solvent such as toluene and ethyl acetate, the surface resistance was maintained within the range of 10 ¹⁰ Ω / sq, thereby confirming the excellent solvent resistance that the antistatic agent of the antistatic layer was not dropped or dissolved. In addition, since the water contact angle is 90 degrees or more, the paper has excellent antifouling performance, and the peeling force with the acrylate-based commercial tape (NITTO # 31B) having a high adhesive strength is 1,000 g / in or more, and at the same time, the paper has a relatively low adhesive force. Peeling force with the commercial tape (3M # 244) of the material also meets more than 150g / 18mm.

Furthermore, the present invention can obtain an antistatic polyester film having excellent coating appearance by implementing low surface tension and excellent wetting performance.

As mentioned above,

First, the antistatic coating composition of the present invention contains a polyurethane resin to improve the peeling force with the adhesive tape and at the same time contains an appropriate crosslinking agent to improve the solvent resistance and coating performance by adjusting the crosslinking density, and contains a fluorine resin It is possible to improve the performance and improve the peeling force and coating property of the tape having a low peeling force by applying an acetylene diol-based surfactant, in particular, by controlling the content of the conductive polymer resin, 10 ⁵ ~ ^{10 10} Ω / Various antistatic performances can be realized within the sq range.

Secondly, by applying the antistatic coating composition of the present invention to one side or both sides of the polyester film, while excellent in transparency and antistatic property, the peeling force and antifouling performance with the adhesive tape is improved, in particular, 10 ^{5-10 10} Ω By implementing various antistatic performance within / sq range, it is possible to provide an antistatic polyester film that can respond quickly to the requirements of the market changes.

Accordingly, the field of application of the antistatic polyester film of the present invention is a liquid crystal display, a plasma display, an organic light emitting diode display, various displays such as an electronic paper display (E-Paper Display), an optical display such as a personal digital assistant, navigation, etc. It will be usefully applied as a surface protective film to the device.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims. .

Claims (12)

To 100 parts by weight of a water dispersible polyurethane resin composed of an anionic polyether polyurethane dispersion comprising at least one functional group selected from the group consisting of a hydroxyl group, an amine group, an alkyl group and a carboxyl group,
50 to 1000 parts by weight of any one crosslinker resin selected from the group consisting of isocyanate series, carbonylimide series, oxazoline series, epoxy series and melamine series,
1 to 100 parts by weight of a fluororesin,
0.1 to 100 parts by weight of an acetylene diol surfactant and
1 to 100 parts by weight of the conductive polymer resin is contained, the antistatic coating composition, characterized in that the surface resistance value is controlled within the range of 10 ⁵ ~ ^{10 10} Ω / sq depending on the content of the conductive polymer resin. The antistatic coating composition according to claim 1, wherein the conductive polymer resin is a water dispersion containing polyanion and polythiophene or a water dispersion containing polyanion and polythiophene derivative. The antistatic coating composition according to claim 2, wherein the water dispersion contains 1 to 5% by weight of polyanion. The antistatic coating composition according to claim 2, wherein the water dispersion contains at least 1 to 40% by weight of polythiophene or polythiophene derivative. The method of claim 1, wherein the fluorine resin is tetrafluoroethylene copolymer, trifluoroethylene copolymer, hexafluoropropylene copolymer, chlorotrifluoroethylene-tetrafluoroethylene copolymer, chlorotrifluoroethylene- The antistatic coating composition, characterized in that at least one selected from the group consisting of polytetrafluoroethylene copolymer, polyvinyl fluoride and polyvinylidene fluoride. The antistatic coating composition of claim 1, wherein the acetylene diol-based surfactant is a compound represented by Formula 1 below:
Formula 1

Wherein R ₁ and R ₄ are C ₃ to C ₁₀ linear or pulverized alkyl group, halogen substituted alkyl group, vinyl group, allyl group, ethynyl group, phenyl group, aryl group, halogen group, C _{3 to} C ₁₀ alkoxy group, a cyano group, an amino group, a hydroxyl group, is selected from a carbonyl group, an ester group or carboxyl group, R _2, R ₃ is an alkyl group of H or _{C 1 ~C 5, m, n} , p, q is an integer from 0 to 20 to be. The antistatic coating composition of claim 1, wherein the content of solids in the antistatic coating composition is 0.5 to 10.0 wt%. On one or both sides of the polyester film,
An antistatic polyester film having an antistatic layer which is coated with the antistatic coating composition of claim ^{1 and} whose antistatic performance is controllable in the range of 10 ⁵ to ^{10 10} Ω / sq. The surface resistance value of before and after cleaning the surface of the said antistatic polyester film with any one organic solvent chosen from the group which consists of ethanol, methyl ethyl ketone, toluene, and ethyl acetate is 1 * 10 <^10> Pa The antistatic polyester film, characterized in that the antistatic property is secured to less than / sq. The antistatic polyester film of claim 8, wherein the antistatic polyester film has a peel force of 1,000 g / in or more with an acrylate tape (NITTO # 31B) and a peel force of 150 g / 18 mm or more with a paper material tape (3M # 244). The antistatic polyester film. The said antistatic polyester film of Claim 8 whose water contact angle of an antistatic polyester film is 90 degree or more. A surface protective film for an optical display device using an antistatic polyester film having an antistatic performance controlled by the surface resistance of 10 ⁵ to ^{10 10} Ω / sq of claim 8.

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