Porous structure for forming anti-fingerprint coating, method of forming anti-fingerprint coating, substrate comprising the anti-finger-print coating formed by the method, and product comprising the substrate

Abstract

Provided are a porous structure for forming anti-fingerprint coating capable of providing a self-cleaning function to a surface of a substrate, a method of forming anti-fingerprint coating using the same, an anti-fingerprint coated substrate prepared by the same method, and a product including the same. When the porous structure including a lipolytic enzyme is formed on the surface of the substrate, contaminants decomposed by an enzyme are absorbed into a pore, and thus anti-fingerprint coating may be more effectively performed to remove detectable contamination from a surface of the substrate. As a result, contamination by fingerprints on the surface of a display device, the appearance of an electronic device, or building materials can be effectively reduced.

Claims

1. A method of forming an anti-fingerprint coating for a display device, comprising: providing a substrate of the display device, which is selected from plastic or glass; and forming a porous structure on a surface of the substrate to obtain the anti-fingerprint coating, wherein the porous structure includes a lipolytic enzyme, and wherein the display device is selected from the group consisting of a liquid crystal display device (LCD), an organic light emitting diode (OLED), and a plasma display device panel (PDP).

2. The method according to claim 1, wherein the lipolytic enzyme is a lipase.

3. The method according to claim 2, wherein the porous structure further comprises at least one enzyme selected from the group consisting of a protease, an amylase, a cellulase, and a lactase.

4. The method according to claim 1, wherein the plastic includes at least one polymer selected from the group consisting of polyester, polypropylene, polyethyleneterephthalate, polyethylenenaphthalate, polycarbonate, triacetylcellulose, olefin copolymers, and polymethylmethacrylate.

5. The method according to claim 1, wherein the lipolytic enzyme is introduced to the porous structure by an adsorption, covalent bonds or an encapsulation.

6. The method according to claim 5, wherein the covalent bonds are formed through a process including treating the surface of the substrate including the porous structure having at least one functional group selected from the group consisting of amino, amide, carboxyl, aldehyde, hydroxyl and thiol groups with a solution including a bifunctional cross-linker; and dipping the substrate in a buffer including the lipolytic enzyme.

7. The method according to claim 5, wherein the covalent bonds are formed through a process including dipping the substrate including the porous structure having an epoxy group in a buffer including the enzyme.

8. The method according to claim 5, wherein the encapsulation is performed by coating the surface of the substrate with a gel matrix, a microcapsule, a hollow fiber or a membrane, and introducing the lipolytic enzyme.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the adhered drawings, in which:

(2) FIG. 1 is a schematic diagram showing a decomposition mechanism of contaminants on an anti-fingerprint coated film of the present invention; and

(3) FIG. 2 is a microscopic photograph showing a state in which a surface of a slide glass prepared by a method of examples is contaminated by fingerprints according to time.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(4) Hereinafter, the present invention will be described with reference to examples and comparative examples in detail. However, the present invention is not limited to these examples.

EXAMPLES

Example 1

Preparation of Anti-Fingerprint Coated Film Using Siloxane-Based Composition and Lipase

(5) 250 g of 3-glycidyloxypropyltrimethoxysilane, 100 g of tetraethoxysilane, and 146 g of methanol were stirred in a flask. 7.3 g of aluminum isopropoxide was added to the obtained mixture, and then stirred again until it became a clear solution. The stirred mixture was cooled to 25 C., and 80 g of citric acid aqueous solution having a pH of 2.5 was dropped and then reacted for several hours. In addition, an aqueous solution prepared of excesses of isopropyl alcohol and titanium isopropoxide, and a trace of acetic acid was reacted during reflow, thereby preparing an intermediate derivative of the titanium isopropoxide. After 60 g of the intermediate derivative of the titanium isopropoxide was added and then reacted for approximately 3 hours, 145 g of acetyl acetone was added and then sufficiently stirred. Afterwards, 200 g of colloid silica dispersed in methanol was added and then maturated for several hours, thereby preparing a siloxane-based composition.

(6) A slide glass was dipped in the prepared siloxane-based composition to coat, and then cured at 110 C. for 2 hours, and thus a porous structure was prepared on the slide glass.

(7) The slide glass was dipped in a PBS buffer having 100 mg/ml of a lipase (Amano Enzyme; Lipase PS Amano SD (23,000 U/g), and then kept at 4 C. for 24 hours. Subsequently, the resulting slide glass was dipped in distilled water to be washed three times for 20 minutes, and blow-dried with nitrogen.

Example 2

Preparation of Anti-Fingerprint Coated Film Using Composition for Hard Coating Agent Including Silica Particles and Lipase

(8) A hard coating solution was prepared by uniformly mixing 7 wt % EB1290 (SK UCB Co., Ltd.) as a reactive acrylate oligomer, 29 wt % dipentaerythritol hexacrylate (DPHA) as a multifunctional acrylate monomer, 11 wt % silica dispersed solution (solid content: 30%) having an average particle size of 15 to 20 nm, which was prepared by dispersing silica particles in methyl isobutyl ketone and methanol, 9 wt % dimethyl formamide (DMF) and 12 wt % isopropyl alcohol (IPA) as solvents, 29 wt % of methyl ethyl ketone (MEK), 2 wt % IRG184 as an initiator, and 1 wt % BYK300 as an additive.

(9) The prepared hard coating composition was coated on a PET film and then UV-cured, thereby preparing a porous structure on the PET film.

(10) The slide glass was dipped in a PBS buffer having 100 mg/ml of a lipase (Amano Enzyme; Lipase PS Amano SD; 23,000 U/g), and then kept at 4 C. for 24 hours. Subsequently, the resulting slide glass was dipped in distilled water to be washed three times for 20 minutes, and blow-dried with nitrogen.

Example 3

Preparation of Anti-Fingerprint Coated Film Using Siloxane-Based Composition, Lipase, and Protease

(11) A slide glass coated with the siloxane-based porous structure prepared as described in Example 1 was dipped in a PBS buffer having 50 mg/ml of a lipase (Amano Enzyme; Lipase PS Amano SD; 23,000 U/g) and 50 mg/ml of a protease (Novozymes; Esperase), and kept at 4 C. for 24 hours. Then, the slide glass was dipped in distilled water to be washed three times for 20 minutes, and blow-dried with nitrogen.

Comparative Example 1

Preparation of Lipase-Introduced Anti-Fingerprint Coated Film by Covalent Bonds Using Linkers

(12) A glass substrate was coated with a lipase by the following method: A slide glass whose surface was coated with amino alkyl silane was reacted in 10% glutaraldehyde solution for 2 hours. Subsequently, the slide glass was lightly washed with distilled water, dipped in a PBS buffer having 100 mg/ml of a lipase (Amano Enzyme; Lipase PS Amano SD; derived from Burkholderia cepacia), and then kept at a room temperature for 24 hours. The lipase-immobilized slide glass was sufficiently washed with running distilled water, and washed in distilled water for 40 minutes with gentle shaking. Then, the slide glass was taken out, and blow-dried with compressed nitrogen at room temperature. Thus, the preparation of a lipase-coated glass substrate was completed.

Experimental Example 1

Test for Anti-Fingerprinting Performance

(13) To confirm reduction of contamination on a surface, fingerprints were put on a slide glass prepared by the method described in Example 1, and then the slide glass was put into a temperature and humidity tester under conditions including 50 C. and 30% humidity to measure the change in haze with time. The test was performed four times according to fingerprint transfer.

(14) The results are shown in Table 1 (Change in Haze with Time according to Fingerprint Transfer)

(15) TABLE-US-00001 TABLE 1 Change in Haze Value (H increased Time by fingerprint transfer) Right After 0.8 1.4 1.9 3.2 Transfer 1 H 0.1* 0.4 0.8 1.7 3 H 0.0* 0.3* 0.5 1.2 5 H 0.0* 0.2* 0.2* 0.7 24 H 0.0* 0.1* 0.1* 0.1* *level at which it was difficult to detect whether contamination by fingerprints occurred or not at first glance

(16) As shown in Table 1, the numbers show that the contaminants were removed with time from the slide glass prepared by Example 1, and thus the haze value was gradually reduced with time.

(17) Meanwhile, the fingerprint removal with time from the slide glass prepared by Example 1 was examined under a microscope, and then the photograph was compared with that of Comparative Example (reference), that is, the non-anti-fingerprint coated slide glass, in FIG. 2. The microscopic examination was performed with 75 magnification.

(18) As shown in FIG. 2, it was visualized that contaminants were removed from a surface of the slide glass prepared by the method described in Example 1 with time.

Experimental Example 2

Test for Anti-Fingerprinting Performance

(19) To confirm reduction of contamination on a surface, fingerprints were put on a slide glass prepared by the method described in Example 2, and then the slide glass was put into a temperature and humidity tester under conditions including 50 C. and 30% humidity to measure the change in haze with time.

(20) The results are shown in Table 2 (Change in Haze with Time according to Fingerprint Transfer)

(21) TABLE-US-00002 TABLE 2 Time Change in Haze Value Right After 2.4 Transfer 2 H 0.4 5 H 0.3 24 H 0.3

(22) As shown in Table 2, the numbers show that contaminants were removed from a surface of the PET film prepared by the method described in Example 2 with time and the haze values were gradually removed with time.

Experimental Example 3

Test for Anti-Fingerprinting Performance

(23) To confirm reduction of contamination on a surface, fingerprints were put on a slide glass prepared by the methods described in Examples 1 and 3, and then the slide glass was put into a temperature and humidity tester under conditions including 50 C. and 30% humidity to measure the change in haze with time. The results are shown in Table 3 (Change in Haze with Time according to Fingerprint Transfer).

(24) TABLE-US-00003 TABLE 3 Example 1 Example 3 (Coated with Lipase) (Lipase + Protease) Time Change in Haze Value Change in Haze Value Right After 2.1 2.0 Transfer 2 H 0.6 0.3 5 H 0.3 0.2 24 H 0.1 0.0

(25) As shown in Table 3, the numbers show that contaminants were removed from a surface of the PET film prepared by the method described in Example 3 with time and the haze values were gradually removed with time. It was confirmed that the performance was improved when the protease was used with the lipase, compared to when the lipase was used alone.

Experimental Example 4

Test for Anti-Fingerprinting Performance

(26) To confirm reduction of contamination on a surface, fingerprints were put on a slide glass prepared by the methods described in Example 1 and Comparative Example 1, and then the slide glass was put into a temperature and humidity tester under conditions including 50 C. and 30% humidity to measure the change in haze with time. The results are shown in Table 4 (Change in Haze with Time according to Fingerprint Transfer).

(27) TABLE-US-00004 TABLE 4 Comparative Example 1 Example 1 (with Porous (without Porous Coated Layer) Coated Layer) Time Change in Haze Value Change in Haze Value Right After 2.1 2.4 Transfer 2 H 0.3 1.8 5 H 0.1 1.6 24 H 0.0 1.2

(28) As shown in Table 4, the number shows that contaminants were more easily removed from the slide glass prepared by the method described in Example 1 with time, than from the slide glass prepared by the method described in Comparative Example 1. As a result, it was confirmed that the performance of removing contaminants by the porous structure was significantly improved, compared to when the porous structure was not formed.

(29) When a porous structure including a lipolytic enzyme according to the present invention is formed on a surface of a substrate, contaminants decomposed by an enzyme are absorbed into a pore, and thus anti-fingerprint coating may be more effectively performed to remove detectable contamination from a surface of the substrate. As a result, contamination by fingerprints on the surface of a display device, the appearance of an electronic device, or building materials can be effectively reduced.

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