KR20010058446A - Antistatic transparent hard coating composition and coating method of plastic surface using the same - Google Patents

Abstract

PURPOSE: An antistatic and transparent hard coating composition is provided, which has excellent physical properties such as scratch-resistance, wear-resistance and the like, also has excellent transparency and provides beautiful external appearance when being coated on transparent plastic. And a method for coating the surface of plastic by using the same is also provided. CONSTITUTION: The antistatic transparent hard coating composition comprises: (i) 6-20 wt.% of a polythiophene conductive polymer aqueous solution; (ii) 10-50 wt.% of an ultraviolet rays hardened type acrylic monomer; (iii) 42-81 wt.% of an organic solvent; (iv) 2-7 wt.% of a photo-initiator; and (iv) 0.05-1.0 wt.% of an ultraviolet rays stabilizer and absorbing agent. The method for coating the surface of plastic comprises steps of: (i) after coating a plastic base plate with the antistatic and transparent hard coating composition, drying it at a temperature of 30-60 deg.C for 1-10 minutes to completely remove the organic solvent from the mixture composition; and (ii) irradiating ultraviolet rays having a light amount of 200-600 millijoule per square centimeters to the plastic base plate of the step (i) to form a coating film.

Description

Antistatic transparent hard coating agent composition and coating method of plastic surface using same {ANTISTATIC TRANSPARENT HARD COATING COMPOSITION AND COATING METHOD OF PLASTIC SURFACE USING THE SAME}

The present invention relates to an antistatic transparent hard coating agent composition for protecting the plastic surface and a coating method of the plastic surface using the same, and more particularly, in the photocurable transparent hard coating agent composition, poly as a conductive material imparting antistatic properties The present invention relates to an antistatic transparent hard coating agent composition having excellent transparency as well as improved thiophene-based conductive polymer and improved physical properties such as scratch resistance and abrasion resistance, and a coating method of a plastic surface using the same.

In general, the plastic hard coating agent is used for coating to protect the surface of plastic materials such as automotive exterior parts, building materials, soundproof walls, optical materials, cosmetic containers using plastics, and the like.

Examples of the prior arts for such hard coating agents of plastics are described in Japanese Patent Laid-Open No. 5-214044, Japanese Patent Laid-Open No. 5-214045, Japanese Patent Laid-Open No. 5-320462, Japanese Patent Laid-Open No. 5-186534, and the like. However, such plastic hard coating agents in the prior art generally have no antistatic property, and even if they are antistatic, an ion conductive material is added and thus the antistatic property is often degraded over time. On the other hand, in the case of mixing a metal and carbon powder having excellent antistatic durability, there is a problem in the chromaticity has been required to develop an antistatic plastic hard coating agent that can provide satisfactory physical properties.

In accordance with such technical requirements, an antistatic hard coating agent using a conductive sol of a metal oxide type such as ATO (antimontinoxide), ITO (indiumtinoxide), etc. has recently been developed as a plastic hard coating agent. In such coatings, commercial applications are very active due to excellent antistatic persistence due to free electron charge transfer and excellent transparency. However, when the hard coating agent is coated on the transparent plastic, the permeability is low, such as 80% to 85%, and the color of the blue tone impairs the appearance of the transparent plastic, and the coating liquid itself is very expensive, so There is a problem that the cost is not suitable for commercial applications.

Accordingly, an object of the present invention is to overcome the problems of transparency and price of the ATO sol and ITO sol metal oxide conductive sol as described above, and by adding a low-cost polythiophene conductive polymer, excellent transparency and very low cost coating It is to provide an antistatic transparent hard coating agent composition that can lower the cost of the plastic product.

Another object of the present invention is to provide a surface coating method of a plastic product using the antistatic transparent hard coating agent composition of the present invention.

That is, one aspect of the present invention is an antistatic hard coating composition of a transparent plastic comprising an ultraviolet curable acrylic monomer, an organic solvent, a photoinitiator, an ultraviolet absorber, and a stabilizer, wherein the polythiophene-based conductive polymer aqueous solution is included. It is to provide an antistatic transparent hard coating agent composition.

According to another aspect of the present invention, the composition is uniformly mixed, coated on a transparent plastic substrate such as acrylic and polycarbonate, and then dried for 1 to 10 minutes in a temperature range of 30 to 80 ° C. to completely remove the organic solvent in the mixed composition. It is a surface coating method of the plastic comprising the step of forming an antistatic hard coating film by curing with an ultraviolet light amount of 200 to 600mJ / cm 3.

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

The antistatic transparent hard coating agent composition of the present invention is characterized by including an inexpensive polythiophene-based conductive polymer aqueous solution as a conductive material to impart antistatic properties.

Preferred antistatic transparent hard coating agent composition of the present invention is an example

Polythiophene-based conductive polymer aqueous solution; 6 to 20% by weight,

Ultraviolet curing acrylic monomers; 10 to 50 weight percent,

Organic solvents; 42 to 81 weight percent,

Photoinitiators; 2 to 7% by weight,

The UV stabilizer and the absorbent are included in an amount of 0.05 to 1.0 wt%.

As a conductive polymer compound, polyaniline, polypyrrol, polythiophene and the like are widely used. These polymer compounds have been attracting attention as synthetic metals for a long time due to their easy polymerization and excellent electrical conductivity, and have been proposed for their application as various conductive materials such as electromagnetic wave materials, secondary battery electrodes and transparent electrodes. . However, since they are difficult to process and have very low safety against heat, air, and ultraviolet light, only a few have actually been commercialized.

Polythiophene-based conductive polymers used in the present invention are characterized by excellent solubility, excellent air, heat, and UV resistance compared to other conductive polymers such as polyaniline and polypyrrole, and thus, due to durability problems. The present invention can also be applied to the formation of a conductive coating film on an externally exposed portion that could hardly be used. In addition, polythiophene-based conductive polymers can be prepared in aqueous solution because they are doped with high molecular acid (polytalensulfonic acid), and this aqueous polymer solution is easily mixed with alcohol solvents, so it is rarely used as a conductive polymer. Demonstrate properties. In particular, when the coating film is formed on the plastic surface, it can be used as a conductive coating such as electromagnetic wave shielding material, antistatic material by coating on a transparent substrate such as CRT glass surface, transparent plastic surface (panel, film) because of excellent permeability. Particularly preferred polytheophene-based conductive polymer in the present invention is polyethylenedioxythiophene having a solid content of 1.3 to 1.5% by weight.

In the antistatic transparent hard coating agent composition of the present invention, the amount of the polythiophene-based conductive polymer aqueous solution (1.3 to 1.5 wt%) is preferably 6 to 20 wt%. If the content of the polytheophene-based conductive polymer aqueous solution is less than 6% by weight, the surface conductivity is weakened, so that the antistatic property cannot be properly exhibited. On the contrary, if the content is more than 20% by weight, the surface conductivity is improved, but the hardness of the coating film is weakened. .

In the composition of the present invention, the ultraviolet curable acrylic monomer may be a monomer in which one or two or more monomers selected from the group consisting of a monofunctional monomer, a bifunctional monomer, and a trifunctional or higher polyfunctional monomer are used. In the present invention, a monofunctional or trifunctional or more trifunctional group may be used alone, but most preferably, a hybrid acrylic monomer in which one or more trifunctional or more functional groups are suitably combined is used. In general, the acrylic monomer having four or more functional groups may exhibit high speed curing and high hardness in the antistatic hard coating agent composition, but may exhibit a problem in that the coating film is easily peeled off from the substrate and the impact resistance is low due to the low flexibility. In addition, the acrylic monomer having a trifunctional or less functional group greatly contributes to improving the flexibility of the coating film, but has a problem in improving the strength of the coating film.

In the present invention, the acrylic monomer having one or more trifunctional groups in the functional group may be all known ones. For example, in the case of the monofunctional group, allyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, Isodecyl methacrylate, isodecyl acrylate, 2-dodecylthioethyl methacrylate, octyl acrylate, 2-methoxyethyl acrylate, 2-hydroxyethyl methacrylate, isooctyl acrylate, urethane acrylate Etc. Examples of bifunctional groups include polyethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, bisphenol A-ethylene glycol diacrylate, 1,4-butanediol diacrylate, epoxy acrylate, and the like. Examples of the trifunctional or more than trifunctional group include pentacrylthiotol tetraacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, pentacrythritol hexaacrylate, pentacrythritol pentaacrylate, and pentaac Rititol triacrylate, and the like.

In the present invention, the content of the ultraviolet curable acrylic monomer is preferably 10 to 50% by weight, the content is less than 10% by weight of the coating film becomes weak, when the content exceeds 50% by weight not only the hardness of the coating film is too high but also the surface conductivity Is low, which is undesirable.

In the composition of the present invention, a dilution solvent is used in order to maintain the thickness control and good coating property of the coating film. As such diluent solvents, any solvent having no compatibility with PEDT conductive polymers and acrylic monomers can be used. For example, methanol, ethanol, isopropanol, propanol, butanol, isobutanol, ethyl cellosolve, methyl cellosolve, butyl acetate, dimethylformamide, diacetone alcohol, ethylene glycol isopropyl alcohol, propylene glycol isopropyl alcohol, methyl Ethyl ketone, N-methylpyrrolidone (N-methylpyrolydone) and the like. The organic solvent may be used alone, but most preferably, two or more solvents having different boiling points are mixed to maintain good film appearance properties and coating film uniformity.

The organic solvent in the composition of the present invention is preferably 42 to 81% by weight. If the content of the organic solvent is less than 42% by weight, there is a problem in coating property, so that a uniform film cannot be formed. When the content of the organic solvent exceeds 81% by weight, the thickness of the coating film becomes too thin to reduce the surface conductivity.

On the other hand, the antistatic transparent hard coating agent composition of the present invention uses a photoinitiator in order to sufficiently proceed the internal and surface curing of the coating film, the photoinitiator is usually used in the technical field to which the present invention belongs, such as hydroxycyclohexylphenyl ketone Photoinitiator can be used. The content of the photoinitiator in the composition of the present invention is preferably 2 to 7% by weight. If the content of the photoinitiator is less than 2% by weight, the surface hardening will not be sufficient. If the content of the photoinitiator is greater than 7% by weight, the surface hardening is good but the reaction is too fast, resulting in poor film flexibility.

In the antistatic transparent hard coating agent composition of the present invention, a small amount of UV stabilizer such as propylene wax and an ultraviolet absorbent may be added for long term stability, and the amount thereof is about 0.05 to 1.0% by weight. Is suitable.

Now, the surface coating method of the transparent plastic using the antistatic transparent hard coating agent composition of the present invention described above.

First, when the surface of the plastic is coated using the hard coating agent composition of the present invention, the composition of the present invention having the above composition and content ratio is mixed uniformly. At this time, by adjusting the amount of the organic solvent to adjust the viscosity of the hard coating agent composition in the range of 5 to 200 cps at 30 ℃ dip coating (flow coating), flow coating (spray coating), roll coating ( roll coating) to obtain a mixed composition. Subsequently, the mixed composition thus obtained is coated on a plastic substrate by the above coating method or the like, and then dried for 1 to 10 minutes at a temperature range of 30 to 60 ° C. to completely remove the organic solvent in the mixed composition, followed by 200 to 600 mJ / cm 2 Ultraviolet rays are irradiated to obtain a completely cured coating film.

In the present invention, the substrate may be a polycarbonate or polymethymethyl methacrylate, and the like, but is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for explaining the present invention and are not intended to limit the claims of the present invention.

Examples 1-8 and Comparative Examples 1-4

After mixing well the hard coating composition of the composition as shown in Table 1, flow coating on an acrylic sheet, and dried at about 60 ℃ for about 10 minutes to completely remove the organic solvent in the mixed composition, the ultraviolet light of about 400mJ / cm 3 light amount Was investigated to obtain a sheet coated with a hard coating agent. Subsequently, the physical properties of the prepared coating film were evaluated, and the results are shown in Table 1 together.

Polythiophene Conductive Polymer UV Curable Acrylic Monomer Organic solvent Photoinitiator UV stabilizer / absorber Example 1 PEDT (aq, 1.3%) = 10% TMPTA / R-551 / PEG (400) DA = 2.8% / 3.8% / 13.4% IPA / MC (1/1) = 64% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 2 PEDT (aq, 1.3%) = 15% TMPTA / R-551 / PEG (400) DA = 4.3% / 5.7% / 20% IPA / MC (1/1) = 54% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 3 PEDT (aq, 1.3%) = 18% TMPTA / R-551 / PEG (400) DA = 5.3% / 7.2% / 25.5% IPA / MC (1/1) = 61% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 4 PEDT (aq, 1.3%) = 8% TMPTA / R-551 / PEG (400) DA = 2.1% / 2.9% / 10.0% IPA / MC (1/1) = 70% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 5 PEDT (aq, 1.3%) = 12% PE-4A / PE-3A / THF-A = 11% / 9.4% / 3.6% IPA / EC (1/1) = 58% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 6 PEDT (aq, 1.3%) = 8% PE-4A / PE-3A / THF-A / monomer-β = 4.7% / 5.5% / 1.8 IPA / MC / NVP (1/1 / 0.2) = 74 Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 7 PEDT (aq, 1.3%) = 10% PE-4A / PE-3A / THF-A / monomer-β = 4.7% / 5.5% / 1.8 IPA / MC / NVP (1/1 / 0.2) = 72% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Example 8 PEDT (aq, 1.3%) = 10% MR-200 / PE-4A = 10% / 10% EtOH / MC (1/1) = 64 $ Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Comparative Example 1 PEDT (aq, 1.3%) = 3% TMPTA / R-551 / PEG (400) DA = 2.8% / 3.8% / 13.4% IPA / MC (1/1) = 71% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Comparative Example 2 PEDT (aq, 1.3%) = 15% TMPTA / R-551 / PEG (400) DA = 20% / 20% / 20% IPA / MC (1/1) = 19% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Comparative Example 3 PEDT (aq, 1.3%) = 25% PE-4A / PE-3A / THF-A = 11% / 9.4% / 3.6% IPA / EC (1/1) = 45% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12% Comparative Example 4 PEDT (aq, 1.3%) = 18% PE-4A / PE-3A / THF-A = 15% / 15% / 11% IPA / EC (1/1) = 35% Irg # 500 = 5% BYK-307 / Tinubin3270 = 0.8% / 0.12%

* PEDT; Baytron PH (Grade PH 4071) of Bayer Corporation,

* DPHA; Pentacrythritol hexaacrylate (six functional: SATOMER Co., Ltd.),

* TMPTA; Trimethylpropane triacrylate (trifunctional: SATOMER Co., Ltd.),

* R-551; Bisphenol A-ethylene glycol diacrylate (bifunctional: Japanese chemical),

* PEG 400 DA; Polyethylene glycol diacrylate (2 functional: SATOMER Co., Ltd.),

* PE-4A; Pentaerythritol acrylate (2 functional: Nippon Chemical Co., Ltd.)

* THF-A; Tetrahydrofuryl acrylate (SATOMER Co., Ltd.),

Monomer (β); Polyethylene glycol, monomethacrylate, polyethylene glycol

Mono- or polyfunctional monomers containing dimethacrylate (Japanese Chemical),

* IPA; Isopropanol / MC; Methyl cellosolve / EC; ethyl cellosolve / NMP; N-methylpyrrolidone

* Irg # 500; 1-hydroxycyclohexyl phenyl ketone (Shibagaiki Co., Ltd.),

* BYK-307; Propylene wax (BYK company),

Tinubin327 (Shibagai Company).

Surface Resistance (MΩ /?) Pencil hardness (H) Scratch resistance Transmittance Adhesion Weather resistance Outer appearance Example 1 350 4H Great 98% 100/100 Great Great Example 2 200 4H Great 96% 100/100 Great Great Example 3 100 5H Great 95% 100/100 Great Great Example 4 300 3-4H usually 97% 100/100 Great Great Example 5 400 4H Great 96% 100/100 Great Great Example 6 200 3-4H usually 99% 100/100 Great Great Example 7 120 3-4H usually 97% 100/100 Great Great Example 8 410 4-5H Great 97% 100/100 Great Great Comparative Example 1 100000 4H Great 99% 100/100 Great Great Comparative Example 2 150000 5H Great 97% 100/100 Great Great Comparative Example 3 80 1-2H usually 94% 90/100 Great usually Comparative Example 4 60 4H Great 95% 100/100 Great Bad

[ Property evaluation method]

Surface resistance; It evaluated by the ultrahigh resistance machine (Advantest).

Visible light transmittance; Evaluation was made by the ASTM D1003 method.

Pencil hardness; It evaluated by ASTM D3502 (pencil hardness tester, toyoseki) method.

* Scratch resistance; It was evaluated by stiol # 000.

Adhesion; Evaluation was made by the ASTM D3359 method.

Weather resistance; It measured with the sunshine Weather-O-meter (1000 hours, ci65-XWA, Atalas company).

Membrane appearance; It was evaluated by visual observation.

The antistatic transparent hard coating agent composition of the present invention not only has excellent physical properties such as scratch resistance, abrasion resistance, weather resistance, adhesiveness, hardness, etc., but also has excellent transparency, and thus provides a beautiful coating appearance when the transparent plastic is coated and also has a price. It is inexpensive and offers the advantages of commercialization.

Claims (8)

An antistatic transparent hard coating agent composition comprising an ultraviolet curable acrylic monomer, an organic solvent, a photoinitiator, an ultraviolet absorber, and a stabilizer, wherein the antistatic transparent hard coat agent composition comprises a polythiophene-based conductive polymer aqueous solution. The composition of claim 1, wherein said composition is Polythiophene-based conductive polymer aqueous solution; 6 to 20% by weight, Ultraviolet curing acrylic monomers; 10 to 50 weight percent, Organic solvents; 42 to 81 weight percent, Photoinitiators; 2 to 7% by weight, UV stabilizer and absorbent 0.05 to 1.0% by weight An antistatic transparent hard coating agent composition comprising a. The antistatic transparent hard coating composition of claim 1, wherein the polythiophene-based conductive polymer is polyethylene dioxythiophene having a solid content of 1.3 to 1.5 wt%. The antistatic transparent hard coating agent composition according to claim 1, wherein the ultraviolet curable acrylic monomer is selected from the group consisting of mono-, bi-, or tri- or mixtures thereof. The method of claim 1, wherein the organic solvent is methanol, ethanol, isopropanol, propanol, butanol, isobutanol, ethyl cellosolve, methyl cellosolve, butyl acetate, dimethylformamide, diacetone alcohol, ethylene glycol isopropyl alcohol, An antistatic transparent hard coating agent composition, characterized in that at least one member selected from the group consisting of propylene glycol isopropyl alcohol, methyl ethyl ketone, N-methylpyrrolidone. The antistatic transparent hard coat composition of claim 1, wherein the composition has a viscosity of 5 to 200 cps at 30 ° C. The method of claim 1, wherein the composition is coated on a plastic substrate and dried for 1 to 10 minutes at a temperature in the range of 30 to 60 ° C. to completely remove the organic solvent in the mixed composition. Coating method of the plastic surface, characterized in that it comprises. 8. The coating of claim 7 wherein the coating method is one of a dip coating, a flow coating, a spray coating, or a roll coating method. Way.