Coating film and display device

Abstract

One embodiment of the present invention provides a coating film including a substrate film and a coating layer on the substrate film, the coating layer having a water contact angle of 100 degrees or more and a water contact angle after scratching of 98 degrees or more, and a display device including the coating film. Another embodiment of the present invention provides a coating composition for producing the coating layer.

Description

[Technical Field]

[0001] The present invention relates to a coating film, a coating composition, and a display device. [Background technology]

[0002] Light-transmitting films are becoming increasingly important as core materials in the fields of optical and flexible displays. Light-transmitting films are used as a substitute for glass in the display field, particularly due to their light weight, ease of processing, and flexibility. Since general light-transmitting films are known to have lower surface hardness and abrasion resistance than glass, research is underway to improve the abrasion resistance of light-transmitting films in order to apply them to the display field.

[0003] One method for improving the mechanical or optical properties of a light-transmitting film is to provide a coating layer on the surface of the light-transmitting film. A light-transmitting film provided with a coating layer is also called a coating film.

[0004] Meanwhile, a method of inputting information using a touch screen has recently been widely applied to electronic devices such as portable personal digital assistants. However, when information is directly input onto the surface of an electronic device or display device using a hand or a pen, the surface of the electronic device or display device may be contaminated by contact with the hand or the pen.

[0005] Therefore, there is a need for light-transmitting films or coatings that have excellent abrasion resistance while at the same time having excellent resistance to staining from hand or pen touches or have excellent stain release properties. Summary of the Invention [Problem to be solved by the invention]

[0006] An object of one embodiment of the present invention is to provide a coating film having excellent abrasion resistance and excellent scratch resistance.

[0007] An object of one embodiment of the present invention is to provide a coating film having excellent stain resistance, which has a large water contact angle and can maintain a large water contact angle even after scratching.

[0008] Another embodiment of the present invention aims to provide a coating composition for use in producing a coating film having the above-mentioned properties.

[0009] Another embodiment of the present invention aims to provide a display device including the coating film. [Means for solving the problem]

[0010] To solve the above problems, one embodiment of the present invention provides a coating film comprising a substrate film and a coating layer on the substrate film, wherein the coating layer has a water contact angle of 100 degrees or more and a water contact angle after scratching of 98 degrees or more.

[0011] The difference between the water contact angle and the water contact angle after scratching may be 10 degrees or less.

[0012] The coating layer may have a water contact angle of 100 to 120 degrees and a water contact angle after scratching of 98 to 110 degrees.

[0013] The coating layer may have a scratch count of two or less.

[0014] The coating layer may have a water contact angle after eraser abrasion of 95 degrees or greater.

[0015] The difference between the water contact angle and the water contact angle after the eraser is abraded may be 10 degrees or less.

[0016] The coating layer may have a water contact angle after eraser abrasion of 95 degrees to 110 degrees.

[0017] The coating layer may have a curl of 2 mm or less based on a thickness of 10 μm.

[0018] The coating layer may have a crack point radius of 1 mm or less based on a thickness of 10 μm.

[0019] Another embodiment of the present invention provides a coating composition comprising a silane compound and a polymerization curing aid, the silane compound comprising a first silane compound represented by the following Chemical Formula 1, a second silane compound represented by the following Chemical Formula 2, and a third silane compound represented by the following Chemical Formula 3, and the polymerization curing aid comprises a diol and water (HO):

[0020] [Chemical formula 1] JPEG0007778166000001.jpg3543

[0021] [Chemical formula 2] JPEG0007778166000002.jpg3569

[0022] [Chemical formula 3] Si(OR 3 )4

[0023] R 11 is a substituted or unsubstituted C2-C5 unsaturated hydrocarbon group, and R 12 , R 13 and R 14 are each independently a C1 to C5 alkyl group, and R 21 is a single bond or a C1-C4 alkylene group, and R 22 , R 23 and R 24 are each independently a C1 to C5 alkyl group, m is an integer of 3 to 10, and R 3is a C1 to C4 alkyl group.

[0024] The molar ratio of the silane compound to the polymerization curing aid may be in the range of 1:1.2 to 1:1.8.

[0025] The silane compound may contain 80 to 90 mol % of the first silane compound, 1 to 5 mol % of the second silane compound, and 7 to 15 mol % of the third silane compound, based on the total number of moles of the silane compounds.

[0026] The first silane compound may include vinyl trimethoxy silane represented by the following Chemical Formula 4:

[0027] [Chemical formula 4] JPEG0007778166000003.jpg3449

[0028] The second silane compound may include at least one selected from 1H,1H,2H,2H-perfluorooctyltriethoxysilane, 1H,1H,2H,2H-perfluorooctyltrimethoxysilane, 1H,1H,2H,2H-perfluorodecyltrimethoxysilane, and 1H,1H,2H,2H-perfluorodecyltriethoxysilane.

[0029] The third silane compound may include at least one of tetraethyl orthosilicate (TEOS) and tetramethyl orthosilicate (TMOS).

[0030] The diol may include at least one of ethylene glycol, 1,3-propanediol, and 1,4-butanediol.

[0031] The coating composition may further include a base catalyst.

[0032] The coating composition may include 0.05 to 0.1 parts by weight of the base catalyst based on 100 parts by weight of the total silane compound.

[0033] Another embodiment of the present invention provides a coating film including a substrate film and a coating layer formed on the substrate film by a coating composition.

[0034] Another embodiment of the present invention provides a display device including a display panel and the coating film disposed on the display panel. [Effects of the Invention]

[0035] The coating layer according to an embodiment of the present invention has a perfluoro group and can have excellent abrasion resistance, scratch resistance, and stain resistance.

[0036] The coating film according to an embodiment of the present invention having the above coating layer may have a large water contact angle and a large water contact angle after scratching, thereby providing excellent slip properties, stain prevention properties, and stain removal properties.

[0037] According to an embodiment of the present invention, a coating layer prepared using a coating composition including a polyfunctional silane compound may have excellent abrasion resistance and scratch resistance. A coating film according to an embodiment of the present invention including such a coating layer may have excellent abrasion resistance and scratch resistance. In addition, the coating layer of the coating film according to an embodiment of the present invention may have excellent flexibility.

[0038] A display device in which a coating film according to an embodiment of the present invention is attached to the display surface of a display panel can have excellent surface contamination prevention properties, excellent surface contamination removal properties, excellent abrasion resistance and scratch resistance, and excellent flexibility. [Brief explanation of the drawings]

[0039] [Figure 1] 1 is a schematic cross-sectional view of a coating film according to an embodiment of the present invention. [Figure 2] FIG. 1 is a schematic cross-sectional view illustrating measurement of a water contact angle. [Figure 3] FIG. 1 is a schematic cross-sectional view illustrating measurement of curl. [Figure 4] FIG. 1 is a schematic diagram illustrating the measurement of crack point radius. [Figure 5] 1 is a cross-sectional view showing a part of a display device according to an embodiment of the present invention. [Figure 6] FIG. 5 is an enlarged cross-sectional view showing a portion "P" in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0040] The present invention will be described in detail below with reference to examples. The examples described below are presented for illustrative purposes to help a clear understanding of the present invention, and are not intended to limit the scope of the present invention.

[0041] When the terms "include," "have," "perform," etc. are used in this specification, other parts may be added unless the expression "only" is used. When an element is expressed as singular, it includes plural unless otherwise expressly stated. Furthermore, when interpreting an element, it is interpreted as including a margin of error even if there is no other explicit statement.

[0042] In the case of a description of a positional relationship, for example, when the positional relationship of two parts is described using expressions such as "above," "above (upper)," "below," or "to the side," one or more other parts may be located between the two parts unless the expressions "immediately" or "directly" are used.

[0043] When describing a temporal relationship, for example, when the temporal sequence is described using "after," "following," "next to," or "before," it may not necessarily be consecutive, unless the words "immediately" or "directly" are used.

[0044] Although terms such as "first," "second," etc. are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, a first component referred to below may also be a second component within the scope of the technical concept of the present invention.

[0045] The term "at least one" should be understood to include all possible combinations of one or more related items. For example, "at least one of the first, second, and third items" means not only the first, second, or third item, but also all possible combinations of two or more of the first, second, and third items.

[0046] The features of the various embodiments of the present invention may be partially or wholly combined or combined with each other, and various technical interlocking and driving mechanisms may be possible, and the embodiments may be implemented independently of each other or may be implemented together in a related relationship.

[0047] FIG. 1 is a schematic cross-sectional view of a coating film (100) according to one embodiment of the present invention.

[0048] Referring to FIG. 1, a coating film (100) according to one embodiment of the present invention includes a substrate film (110) and a coating layer (120) on the substrate film (110).

[0049] A light-transmitting film may be used as the base film 110. A polyimide-based (PI) film, including a polyimide film and a polyamide-imide film, may be used as the light-transmitting film. However, the present invention is not limited thereto, and polycarbonate (PC), polyacrylic, polyethylene terephthalate, cellulose, etc. may also be used as the base film 110.

[0050] According to one embodiment of the present invention, the coating layer 120 may be made of a coating composition including a silane compound and a polymerization curing aid. The coating layer 120 made of the coating composition including a silane compound and a polymerization curing aid may include a siloxane resin.

[0051] According to one embodiment of the present invention, a perfluorosilane compound may be used to form the coating layer 120. The perfluoro group contained in the perfluorosilane compound may be located on the top of the coating layer. As a result, the perfluoro group may affect the surface properties of the coating layer 120.

[0052] According to one embodiment of the present invention, the coating layer 120 may have excellent abrasion resistance, scratch resistance, stain resistance, and flexibility, so that the coating film 100 including the coating layer 120 may have excellent abrasion resistance, scratch resistance, stain resistance, and flexibility.

[0053] According to one embodiment of the present invention, the coating layer (120) may have a thickness of 5 to 50 μm. If the thickness of the coating layer (120) is less than 5 μm, the abrasion resistance, scratch resistance, and contamination resistance of the coating film (100) due to the coating layer (120) may not be fully exhibited. If the thickness of the coating layer (120) is more than 50 μm, the thickness of the coating film (100) may become too thick, and the flexibility of the coating film (100) may decrease.

[0054] According to one embodiment of the present invention, the coating film (100) may have a water contact angle of 100 degrees or more and a water contact angle after scratching of 98 degrees or more. More specifically, the coating layer (120) of the coating film (100) according to one embodiment of the present invention may have a water contact angle of 100 degrees or more and a water contact angle after scratching of 98 degrees or more.

[0055] According to one embodiment of the present invention, the water contact angle is defined as the angle between the surface of the coating layer (120) and the boundary of the water droplet (H2O), measured after dropping a 5 μL water droplet (H2O) onto the coating layer (120).

[0056] FIG. 2 is a schematic cross-sectional view illustrating the measurement of the water contact angle.

[0057] According to one embodiment of the present invention, a KRUSS MSA (Mobile Surface Analyzer) model is used to determine the water contact angle by dropping a 5 μL water droplet (WD) onto the coating layer (120) as shown in Figure 2, and then measuring the angle (θ) between the surface of the coating layer (120) and the boundary of the water droplet. Specifically, a 5 μL water droplet (WD) is dropped onto the surface of the coating layer (120) at a rate of 2.7 μL / sec, and the angle (θ) between the surface of the coating layer (120) and the boundary of the water droplet (WD) is measured seven times every 0.2 seconds. By repeating this measurement five times, the average value can be determined as the water contact angle.

[0058] The coating layer (120) of the coating film (100) according to one embodiment of the present invention has a water contact angle of 100 degrees or more. A coating layer (120) having a large water contact angle of 100 degrees or more may have excellent slip properties. When the coating layer (120) has excellent slip properties, contaminants are less likely to adhere to or deposit on the coating layer (120), and therefore the coating layer (120) may have excellent contamination prevention properties. Furthermore, when the coating layer (120) has excellent slip properties, contaminants that have adhered to or deposited on the coating layer (120) may be easily removed. As a result, the coating layer (120) may have excellent contamination removal properties.

[0059] The coating layer 120 of the coating film 100 according to one embodiment of the present invention has a water contact angle after scratching of 98 degrees or more.

[0060] The water contact angle after scratching was measured by cutting the coating film (100) to a size of 100 mm x 50 mm to prepare a coating film sample, fixing the coating film sample to a flat surface using adhesive tape (3M) with the coating layer (120) facing upward, and then using a 20 mm x 20 mm stainless steel (SUS) jig wrapped with #0000 (LIBERON) nonwoven fabric, moving the jig back and forth over the surface of the coating layer (120) of the coating film sample at a load of 0.5 kgf and a speed of 45 RPM for 10,000 times.

[0061] In summary, the water contact angle after scratching refers to the water contact angle measured after the surface of the coating layer (120) of the coating film (100) has undergone a scratch induction process. To measure the water contact angle after scratching, a KRUSS MSA (Mobile Surface Analyzer) model can be used.

[0062] The coating layer (120) of the coating film (100) according to one embodiment of the present invention has a water contact angle of 98 degrees or more after scratching, so that the surface of the coating layer (120) can maintain excellent slip properties even after being exposed to a scratching environment. Therefore, even if the coating layer (120) is exposed to a scratching environment during use of the coating film (100), the coating film (100) can maintain excellent contamination prevention and removal properties.

[0063] According to one embodiment of the present invention, the difference between the water contact angle of the coating layer 120 and the water contact angle after scratching may be 10 degrees or less.

[0064] If the difference between the water contact angle of the coating layer 120 and the water contact angle after scratching is not large, this means that the water contact angle of the coating layer 120 will not decrease significantly even if the coating layer 120 is exposed to a scratching environment during use of the coating film 100. As such, the coating film 100 according to an embodiment of the present invention is not significantly damaged in a scratching environment and can have excellent resistance in a scratching environment. Therefore, it can be said that the coating film 100 according to an embodiment of the present invention has excellent scratch resistance.

[0065] According to one embodiment of the present invention, the coating layer (120) may have a water contact angle of 100 to 120 degrees and a water contact angle after scratching of 98 to 110 degrees. Alternatively, according to one embodiment of the present invention, the coating layer (120) may have a water contact angle of 105 to 120 degrees and a water contact angle after scratching of 100 to 110 degrees. According to one embodiment of the present invention, the coating layer (120) may also have a water contact angle of 105 to 115 degrees.

[0066] The coating layer 120 of the coating film 100 according to an embodiment of the present invention may have two or less scratches.

[0067] According to one embodiment of the present invention, the number of scratches is measured by cutting the coating film (100) to a size of 100 mm x 50 mm to prepare a coating film sample, fixing the coating film sample to a flat surface using adhesive tape (3M) with the coating layer (120) facing upward, and then using a 20 mm x 20 mm stainless steel (SUS) jig wrapped with #0000 (LIBERON) nonwoven fabric, moving it back and forth across the surface of the coating layer (120) of the coating film sample at a load of 0.5 kgf and a speed of 45 RPM for 10,000 times, and then observing the number of scratches with the naked eye.

[0068] According to one embodiment of the present invention, the coating layer 120 of the coating film 100 may have one or fewer scratches, or may have no scratches.

[0069] According to one embodiment of the present invention, the coating film 100 has very little or no scratches even after undergoing a scratch induction process, and therefore, it can be said that the coating film 100 according to one embodiment of the present invention has excellent scratch resistance.

[0070] When the coating film 100 according to an embodiment of the present invention is used as a cover window of a display device, the coating film 100 is exposed to a scratching environment. However, since the coating film 100 according to an embodiment of the present invention has excellent scratch resistance, scratches may not occur or may occur very little even when the coating film 100 is used as a cover window of a display device.

[0071] According to one embodiment of the present invention, the coating layer 120 of the coating film 100 may have a water contact angle after eraser abrasion of 95 degrees or more.

[0072] The water contact angle after eraser abrasion was measured by cutting the coating film (100) to a size of 200 mm x 50 mm to prepare a coating film sample, fixing the coating film sample to a flat surface using adhesive tape (3M) with the coating layer (120) facing upward, and then fixing a "Manaslu" eraser (an eraser for abrasion resistance tests; Minoan abrasion test erasers) to the jig. The sample was then subjected to a load of 0.5 kgf and a speed of 45 RPM for 1,000 cycles. The water contact angle was measured after moving the coating layer (120) surface of the coating film sample back and forth. The KRUSS MSA (Mobile Surface Analyzer) model can be used to measure the water contact angle.

[0073] The coating layer 120 of the coating film 100 according to an embodiment of the present invention has a water contact angle of 95 degrees or more after abrasion by an eraser, so even if the coating layer 120 is exposed to an environment that can abrade the surface of the coating layer 120, it can be said that the coating layer 120 is not significantly damaged. Therefore, it can be said that the coating film 100 according to an embodiment of the present invention has excellent abrasion resistance.

[0074] According to an embodiment of the present invention, the difference between the water contact angle of the coating layer 120 and the water contact angle after the eraser is worn may be 10 degrees or less.

[0075] If the difference between the water contact angle of the coating layer 120 and the water contact angle after abrasion by an eraser is not large, this means that the water contact angle of the coating layer 120 will not decrease significantly even if the coating layer 120 is exposed to an environment that may cause abrasion during use of the coating film 100. As such, the coating film 100 according to one embodiment of the present invention is not significantly damaged in an abrasive environment, and therefore can be said to have excellent abrasion resistance.

[0076] According to one embodiment of the present invention, the coating layer 120 of the coating film 100 may have a water contact angle after eraser abrasion of 95 degrees to 110 degrees. Alternatively, the coating layer 120 of the coating film 100 according to one embodiment of the present invention may have a water contact angle after eraser abrasion of 95 degrees to 105 degrees.

[0077] According to one embodiment of the present invention, the coating film 100 may have a curl of 2 mm or less. For example, based on a coating layer 120 having a thickness of 10 μm, the coating film 100 may have a curl of 2 mm or less.

[0078] The curl is defined as the distance between the corner of the coating film sample and the bottom surface of the glass substrate after placing a sample of the coating film (100) cut into a square of 100 mm x 100 mm on a flat glass substrate.

[0079] Figure 3 is a schematic cross-sectional view illustrating the measurement of curl. The distance indicated as "curl" in Figure 3, specifically the distance between the corner of the coating film (100) sample and the floor (top surface) of the glass substrate (201), is the curl of the coating film (100).

[0080] During the manufacturing process of the coating film 100, the coating composition may harden to form the coating layer 120, and curling may occur due to shrinkage during hardening. If curling occurs, the coating film 100 may be distorted in appearance, making post-processing difficult, and if curling is severe, problems such as peeling of the coating layer 120 may occur.

[0081] According to one embodiment of the present invention, the coating composition may contain a diol, which may maintain the distance between molecules contained in the coating composition and prevent curling of the coating film (100) including the coating layer (120).

[0082] According to one embodiment of the present invention, the coating film (100) may have a curl of 1 mm or less, may have a curl of 0.5 mm or less, or may have no curl that is visible to the naked eye.

[0083] According to one embodiment of the present invention, the coating film 100 may have a crack point radius of 1 mm or less. For example, based on a coating layer 120 thickness of 10 μm, the coating film 100 may have a crack point radius of 1 mm or less.

[0084] According to one embodiment of the present invention, the crack point radius is defined as the radius of curvature at which a crack occurs in a coating film sample when the coating film (100) is cut to a size of 20 mm x 100 mm to prepare the coating film sample, and the coating film sample is attached to a radius bending tester so that the coating layer (120) faces the outer direction of the coating film sample being bent, and the coating film sample is bent as the radius of curvature is reduced.

[0085] Fig. 4 is a schematic diagram illustrating the measurement of the crack point radius. As shown in Fig. 4, when bending a sample of the coating film (100), the curvature radius at the bending point is repeatedly reduced, and the curvature radius at which a crack occurs in the sample of the coating film (100) is defined as the crack point radius.

[0086] According to one embodiment of the present invention, the coating film 100 has a very small crack point radius of 1 mm or less, and therefore has excellent flexibility and flexibility.

[0087] In particular, according to one embodiment of the present invention, the coating film sample is attached to a bending tester ("Radius Bending Tester") so that the coating layer (120) faces outward in the direction in which the coating film sample is bent. This results in a more severe crack point radius measurement than when the coating film sample is attached so that the coating layer (120) faces inward in the direction in which the coating film sample is bent. Nevertheless, since the coating film (100) according to one embodiment of the present invention has a very small crack point radius of 1 mm or less, it can be said that the coating film (100) according to one embodiment of the present invention has excellent bending properties and flexibility.

[0088] More specifically, the coating film 100 according to an embodiment of the present invention may have a crack point radius of 0.5 mm or less.

[0089] One embodiment of the present invention provides a coating composition that can be used to form a coating layer (120) on a coating film (100).

[0090] According to one embodiment of the present invention, a coating composition includes a silane compound and a polymerization curing aid. The silane compound may include a first silane compound represented by the following Chemical Formula 1, a second silane compound represented by the following Chemical Formula 2, and a third silane compound represented by the following Chemical Formula 3. The polymerization curing aid may include a diol and water (H2O).

[0091] [Chemical formula 1] JPEG0007778166000004.jpg3543

[0092] In formula 1, R 11 is a substituted or unsubstituted C2-C5 unsaturated hydrocarbon group, and R 12 , R 13and R 14 are each independently a C1 to C5 alkyl group, where the unsaturated hydrocarbon group and the alkyl group may each be linear, branched, or alicyclic.

[0093] [Chemical formula 2] JPEG0007778166000005.jpg3569

[0094] In formula 2, R 21 is a single bond or a C1-C4 alkylene group, and R 22 , R 23 and R 24 are each independently a C1 to C5 alkyl group. Here, the alkylene group and the alkyl group may each be linear, branched, or alicyclic. In Chemical Formula 2, m is an integer from 3 to 10.

[0095] [Chemical formula 3] Si(OR 3 )4

[0096] In formula 3, R 3 is a C1 to C4 alkyl group, where the alkyl group can be linear or branched.

[0097] According to one embodiment of the present invention, a siloxane may be formed from a silane compound. Specifically, the silane compound undergoes a polymerization and curing reaction. The polymerization and curing of the silane compound polymerizes and cures the coating composition, thereby forming the coating layer 120.

[0098] The first silane compound represented by Chemical Formula 1 can undergo a polymerization reaction due to its unsaturated hydrocarbon group. As the main component of the silane compound, the first silane compound can play a central role in polymerizing and curing the coating composition. The first silane compound can facilitate the polymerization and curing of the coating composition.

[0099] The first silane compound may include, for example, vinyl trimethoxy silane represented by the following Chemical Formula 4:

[0100] [Chemical formula 4] JPEG0007778166000006.jpg3449

[0101] The second silane compound is a silane compound having a perfluoro group. The perfluoro group contained in the second silane compound can reduce the surface tension of the coating layer (120) and increase the water contact angle of the coating layer (120), thereby maintaining an excellent contact angle even after scratching or abrasion.

[0102] According to one embodiment of the present invention, the coating composition may include a second silane compound represented by Chemical Formula 2, so that the coating layer (120) has a large water contact angle, excellent slip properties, improves the anti-fouling and anti-fouling properties of the coating layer (120), and simultaneously improves scratch resistance.

[0103] The second silane compound represented by Chemical Formula 2 may include at least one selected from 1H,1H,2H,2H-perfluorooctyltriethoxysilane, 1H,1H,2H,2H-perfluorooctyltrimethoxysilane, 1H,1H,2H,2H-perfluorodecyltrimethoxysilane, and 1H,1H,2H,2H-perfluorodecyltriethoxysilane.

[0104] The coating layer (120) formed by the coating composition containing the second silane compound having a perfluoro group may have a water contact angle of 100 degrees or more and a water contact angle after scratching of 98 degrees or more. Also, the coating layer (120) formed by the coating composition containing the second silane compound having a perfluoro group may have a water contact angle after eraser abrasion of 95 degrees or more.

[0105] The coating layer (120) according to an embodiment of the present invention, which has a large water contact angle, may have excellent slip properties, thereby improving the anti-fouling and anti-fouling properties of the coating layer (120). Furthermore, the excellent slip properties of the coating layer (120) may prevent scratches from occurring on the coating layer (120) in a scratching environment. As a result, the scratch resistance of the coating layer (120) may be improved. Furthermore, the fluorine (F) contained in the second silane compound may improve the abrasion resistance of the coating layer (120).

[0106] The coating layer (120) manufactured using the coating composition according to one embodiment of the present invention has a water contact angle of 98 degrees or more after scratching, and therefore has excellent slip properties even after the surface of the coating layer (120) is exposed to a scratching environment. Therefore, the coating layer (120) can maintain its anti-fouling and anti-fouling properties even after being exposed to a scratching environment.

[0107] The coating layer (120) manufactured using the coating composition according to one embodiment of the present invention has two or fewer scratches after being exposed to a scratching environment. Thus, the coating layer (120) has excellent resistance to the scratching environment and excellent scratch resistance.

[0108] The coating layer (120) manufactured using the coating composition according to one embodiment of the present invention has a water contact angle of 95 degrees or more after abrasion with an eraser, and therefore has excellent slip properties even when exposed to an abrasive environment. As a result, the coating layer (120) can maintain excellent anti-fouling and anti-fouling properties even in an abrasive environment.

[0109] Examples of the second silane compound include 1H,1H,2H,2H-perfluorooctyltriethoxysilane represented by the following chemical formula 5 and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane represented by the following chemical formula 6.

[0110] [Chemical formula 5] JPEG0007778166000007.jpg2780

[0111] [Chemical formula 6] JPEG0007778166000008.jpg2688

[0112] The coating composition according to an embodiment of the present invention may include a third silane compound represented by Formula 3 to improve the mechanical strength, hardness, and scratch resistance of the coating layer (120).

[0113] According to one embodiment of the present invention, the third silane compound has four alkoxy groups. As represented by Chemical Formula 3, the silane compound having four alkoxy groups is also called a Q-structure silane compound.

[0114] According to one embodiment of the present invention, the coating layer (120) formed using the coating composition containing the third silane compound includes a siloxane structure with a Q structure formed in the polymer chain of the siloxane resin, and as a result, the coating layer (120) can have excellent hardness and scratch resistance like glass.

[0115] The third silane compound may include, for example, at least one of tetraethyl orthosilicate (TEOS) and tetramethyl orthosilicate (TMOS).

[0116] An example of the third silane compound is tetraethyl orthosilicate (TEOS) represented by the following chemical formula 7.

[0117] [Chemical formula 7] JPEG0007778166000009.jpg4847

[0118] According to one embodiment of the present invention, the contents of the first silane compound, the second silane compound, and the third silane compound are adjusted to improve the abrasion resistance, scratch resistance, and water contact angle of the coating layer (120) formed by the coating composition.

[0119] For example, if the content of the first silane compound in the coating composition is insufficient, the coating properties and curing properties of the coating composition may be reduced, and the time required for the thermal curing process may be significantly increased. Furthermore, if the content of the first silane compound is insufficient, the scratch resistance of the coating layer may be reduced.

[0120] If the content of the second silane compound in the coating composition is insufficient, the water contact angle of the coating layer formed by the coating composition may decrease, resulting in poor slip properties, whereas if the content of the second silane compound is excessively high, workability and coatability may decrease.

[0121] The third silane compound serves to shorten the polymerization time of the coating composition, thereby improving the abrasion resistance and scratch resistance of the coating layer (120). However, an increase in the content of the third silane compound increases the occurrence of curl in the coating layer (120), and reduces the flexibility and bendability of the coating layer (120). Specifically, if the coating composition contains an excessive amount of the third silane compound, the flexibility of the coating layer (120) formed by the coating composition may decrease. On the other hand, if the content of the third silane compound is insufficient, the silane Q structure may not be sufficiently formed in the polymer chain of the siloxane resin, and the hardness, strength, and scratch resistance of the coating layer formed by the coating composition may decrease.

[0122] Considering these characteristics, according to one embodiment of the present invention, 80 to 90 mol % of the first silane compound, 1 to 5 mol % of the second silane compound, and 7 to 15 mol % of the third silane compound may be used relative to the total moles of the silane compounds.

[0123] More specifically, according to one embodiment of the present invention, 82 to 89 mol % of the first silane compound, 1 to 5 mol % of the second silane compound, and 8 to 12 mol % of the third silane compound may be used relative to the total number of moles of the silane compounds.

[0124] The solvent allows the silane compound to be mixed uniformly and facilitates polymerization of the silane compound.

[0125] According to one embodiment of the present invention, the polymerization curing aid may be used in a larger amount than the silane compound, on a molar basis. For example, to facilitate smooth mixing and polymerization of the silane compound, the molar ratio of the silane compound to the polymerization curing aid may be in the range of 1:1.2 to 1.8 (silane compound:polymerization curing aid = 1:1.2 to 1.8). More specifically, the molar ratio of the silane compound to the polymerization curing aid may be in the range of 1:1.4 to 1.6 (silane compound:polymerization curing aid = 1:1.4 to 1.6).

[0126] According to one embodiment of the present invention, the silane compound may be used in a greater amount than the polymerization curing aid by weight. For example, to form a coating layer 120 with excellent physical properties, the weight ratio of the polymerization curing aid to the silane compound may be in the range of 1:3 to 6 (solvent:silane compound=1:3 to 6).

[0127] The coating composition according to one embodiment of the present invention contains water (H2O) as a polymerization curing aid. Water (H2O) can be used as a binder between monomers to form a siloxane resin and participates in a dehydration condensation reaction.

[0128] The coating composition according to one embodiment of the present invention may include a diol as a polymerization curing aid. The diol serves to maintain the spacing between silane compounds during the curing process of the coating composition, thereby preventing curling of the coating layer (120) or coating film (100) due to the curing of the silane compounds. To maintain the spacing between silane compounds, a linear diol may be used according to one embodiment of the present invention.

[0129] According to an embodiment of the present invention, the diol may include at least one of ethylene glycol, 1,3-propanediol, and 1,4-butanediol.

[0130] Diols suppress curling and increase the flexibility of the coating layer 120. However, increasing the diol content increases the polymerization time of the coating composition and can reduce the abrasion resistance and scratch resistance of the coating layer 120. Taking these characteristics into consideration, the content of water (H2O) and diol can be adjusted.

[0131] For example, water (H2O) and diol can be used in a molar ratio of 1:0.5 to 0.9 (water:diol = 1:0.5 to 0.9). More specifically, the molar ratio of water (H2O) to diol can be in the range of 1:0.6 to 0.8 (water:diol = 1:0.6 to 0.8).

[0132] According to one embodiment of the present invention, a greater amount of diol than water (H2O) may be used by weight. For example, water (H2O) and diol may be used in a weight ratio of 1:1.5 to 3 (water:diol = 1:1.5 to 3). More specifically, the weight ratio of water (H2O) to diol may be in the range of 1:1.5 to 2.5 (water:diol = 1:1.5 to 2.5).

[0133] The coating composition according to one embodiment of the present invention may include a catalyst, which may, for example, promote the formation of a siloxane resin necessary to form the coating layer 120.

[0134] According to one embodiment of the present invention, the catalyst may be an acid catalyst such as hydrochloric acid, acetic acid, hydrogen fluoride, nitric acid, sulfuric acid, or iodic acid; a base catalyst such as ammonia, potassium hydroxide, sodium hydroxide, barium hydroxide, or imidazole; or an ion exchange resin such as Amberlite. These catalysts may be used alone or in combination. The catalyst may be added in an amount of 0.0001 to about 10 parts by weight based on 100 parts by weight of the siloxane compound, but the amount of the catalyst is not limited thereto.

[0135] The coating composition according to an embodiment of the present invention may include a base catalyst. Sodium hydroxide (NaOH) may be used as the base catalyst. The coating composition may include 0.05 to 0.1 parts by weight of the base catalyst based on 100 parts by weight of the total silane compound.

[0136] The coating composition according to an embodiment of the present invention may further include one or more additives selected from the group consisting of a polymerization initiator, an antioxidant, a leveling agent, and a coating aid.

[0137] According to one embodiment of the present invention, the polymerization initiator may be, for example, a photopolymerization initiator such as an organic metal salt, or a thermal polymerization initiator such as an amine or imidazole, and may be used in an amount of about 0.01 to 2 parts by weight per 100 parts by weight of the siloxane resin.

[0138] According to one embodiment, an organic solvent may be used to form the coating layer 120. The organic solvent controls the viscosity of the coating composition, thereby controlling the processability of the coating composition and allowing for easy adjustment of the thickness of the coating layer 120.

[0139] As the organic solvent, one or more selected from the group consisting of ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, cyclohexanone, etc.; cellosolves such as methyl cellosolve, butyl cellosolve, etc.; ethers such as ethyl ether, dioxane, etc.; alcohols such as isobutyl alcohol, isopropyl alcohol, butanol, methanol, etc.; halogenated hydrocarbons such as dichloromethane, chloroform, trichloroethylene, etc.; and hydrocarbons such as normal hexane, benzene, toluene, etc. may be used.

[0140] According to one embodiment of the present invention, the coating layer 120 may be formed by polymerizing and curing a coating composition.

[0141] More specifically, the coating composition is pre-polymerized to form a paste-like prepolymer, and an organic solvent is added to the prepolymer to prepare a paste-like coating composition with adjusted viscosity. The coating composition is then coated onto the substrate film (110), and cured and polymerized to form the coating layer (120).

[0142] During the formation of the coating layer (120), a siloxane resin may be formed from the coating composition. For example, the siloxane resin may be formed through a substitution reaction and condensation polymerization of an alkoxydiol. During the formation of the siloxane resin, the alkoxy may undergo a substitution reaction (or hydrolysis) with water, resulting in condensation polymerization. This reaction may proceed at room temperature, but to accelerate the reaction, stirring may be performed at 50°C to 120°C for 1 hour to 20 hours.

[0143] According to one embodiment of the present invention, the coating composition according to one embodiment of the present invention may be coated on a substrate film (110) by a method such as coating, casting, or molding, and then photopolymerized or thermally polymerized to form a coating layer (120).

[0144] When the coating composition is polymerized, the light intensity condition suitable for photopolymerization is 50 mJ / cm 2 More than 20,000mJ / cm 2 Before light irradiation, the film may be heat-treated at a temperature of 40° C. to about 200° C. to obtain a uniform surface. The temperature suitable for thermal polymerization is 40° C. to 200° C., but is not limited thereto.

[0145] FIG. 5 is a cross-sectional view showing a part of a display device (200) according to another embodiment of the present invention, and FIG. 6 is an enlarged cross-sectional view showing part "P" in FIG.

[0146] Referring to Fig. 5, a display device (200) according to another embodiment of the present invention includes a display panel (501) and a coating film (100) on the display panel (501). Fig. 5 discloses a display device (200) including the coating film (100) of Fig. 1.

[0147] 5 and 6, the display panel 501 includes a substrate 510, a thin film transistor (TFT) on the substrate 510, and an organic light emitting element 570 connected to the thin film transistor (TFT). The organic light emitting element 570 includes a first electrode 571, an organic light emitting layer 572 on the first electrode 571, and a second electrode 573 on the organic light emitting layer 572. The display device 200 disclosed in FIGS. 5 and 6 is an organic light emitting display device.

[0148] The substrate 510 may be made of plastic, specifically, polyimide resin or polyimide film.

[0149] Although not shown, a buffer layer may be disposed on the substrate 510 .

[0150] The thin film transistor (TFT) is disposed on the substrate 510. The thin film transistor (TFT) includes a semiconductor layer 520, a gate electrode 530 insulated from the semiconductor layer 520 and overlapping at least a portion of the semiconductor layer 520, a source electrode 541 connected to the semiconductor layer 520, and a drain electrode 542 spaced from the source electrode 541 and connected to the semiconductor layer 520.

[0151] 6, a gate insulating layer 535 is disposed between a gate electrode 530 and a semiconductor layer 520. An interlayer insulating layer 551 may be disposed on the gate electrode 530, and a source electrode 541 and a drain electrode 542 may be disposed on the interlayer insulating layer 551.

[0152] The planarization film (552) is disposed on the thin film transistor (TFT) and flattens the top of the thin film transistor (TFT).

[0153] The first electrode (571) is disposed on the planarization film (552). The first electrode (571) is connected to the drain electrode (542) of the thin film transistor (TFT) through a contact hole provided in the planarization film (552). The first electrode (571) may also be connected to the source electrode (541).

[0154] The bank layer 580 is disposed on the first electrode 571 and the planarization film 552, and defines a pixel region or a light-emitting region. For example, the bank layer 580 may be disposed in a matrix structure in the boundary region between a plurality of pixels, thereby defining the pixel region.

[0155] The organic light-emitting layer 572 is disposed on the first electrode 571. The organic light-emitting layer 572 may also be disposed on the bank layer 580. The organic light-emitting layer 572 may include one light-emitting layer or may include two or more light-emitting layers stacked one above the other. The organic light-emitting layer 572 may emit light having one of red, green, and blue colors, or may emit white light.

[0156] A second electrode (573) is disposed on the organic light-emitting layer (572).

[0157] The organic light emitting element (570) may be formed by stacking a first electrode (571), an organic light emitting layer (572), and a second electrode (573).

[0158] Although not shown, when the organic light emitting layer 572 emits white light, each pixel may include a color filter for filtering the white light emitted from the organic light emitting layer 572 by wavelength. The color filter is formed on the path of light.

[0159] A thin film encapsulation layer 590 may be disposed on the second electrode 573. The thin film encapsulation layer 590 may include at least one organic film and at least one inorganic film, and the at least one organic film and the at least one inorganic film may be alternately disposed.

[0160] A coating film 100 is disposed on the display panel 501 having the above-described laminated structure. The coating film 100 can be used as a cover window that covers and protects the light-emitting surface of the display panel 501.

[0161] The present invention will be described in more detail below with reference to specific examples and comparative examples. These examples and comparative examples are intended to explain the present invention in more detail, and are not intended to limit the present invention.

[0162] [Comparative Example 1] A 500 mL flask was charged with 148 g (1 mol) of vinyl trimethoxysilane (Shin-Etsu Corporation, KBM-1003), 27 g (1.5 mol) of water (HO), and 0.1 g of NaOH (SAMCHUN CHEMICALS), and the mixture was stirred at 100 rpm using a mechanical stirrer at 65°C for 5 hours to produce a prepolymer.

[0163] 10 g of the prepared prepolymer was mixed with 10 g of methyl ethyl ketone (MEK), an organic solvent, and 0.1 g of IRGACURE 184 (BASF), a photoinitiator, to prepare a coating composition paste. The prepared coating composition paste was applied to a 50 μm thick polyimide film (CPI, KOLON), which served as a substrate film (110), using a Mayer Bar No. 8, to form a coating layer (120). As a result, an uncured coating film was prepared.

[0164] The uncured coating film was dried in an oven at 100°C for 10 minutes and then exposed to a UV lamp (150 mW / cm) for 30 seconds. 2 , 2J / cm 2 ) to harden the coating layer (120). As a result, a coating film (100) having a coating layer (120) with a thickness of 10 μm was completed.

[0165] Comparative Example 2 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 148 g (1 mol) of vinyltrimethoxysilane (Shin-Etsu Co., KBM-1003), 19 g (1.05 mol) of water (HO), 28 g (0.45 mol) of ethylene glycol (EG) (Sigma-Aldrich Co.), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 7 hours to prepare a prepolymer. (Mole ratio HO:EG = 7:3)

[0166] Comparative Example 3 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 148 g of vinyltrimethoxysilane (Shin-Etsu Co., KBM-1003), 16 g (0.9 mol) of water (HO), 37 g (0.6 mol) of ethylene glycol (EG, Sigma Aldrich Co.), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 10 hours to prepare a prepolymer. (Mole ratio: HO:EG = 6:4)

[0167] Comparative Example 4 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 148 g (1 mol) of vinyltrimethoxysilane (Shin-Etsu Co., KBM-1003), 14 g (0.75 mol) of water (HO), 47 g (0.75 mol) of ethylene glycol (EG, Sigma Aldrich Co.), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 12 hours to prepare a prepolymer. (Mole ratio HO:EG = 5:5)

[0168] Comparative Example 5 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 148 g (1 mol) of vinyltrimethoxysilane (Shin-Etsu Co., KBM-1003), 11 g (0.6 mol) of water (HO), 56 g (0.9 mol) of ethylene glycol (EG, Sigma Aldrich Co.), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 24 hours to prepare a prepolymer. (Mole ratio HO:EG = 4:6)

[0169] Comparative Example 6 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 147 g (0.99 mol) of vinyltrimethoxysilane (Shinetsu, KBM-1003), 2 g (0.01 mol) of TEOS (Evonik), 16 g (0.9 mol) of water (HO), 37 g (0.6 mol) of ethylene glycol (EG, Sigma Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 9 hours to prepare a prepolymer. (Mole ratio: KBM-1003:TEOS = 99:1, HO:EG = 6:4)

[0170] Comparative Example 7 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 141 g (0.95 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 10 g (0.05 mol) of TEOS (Evonik), 16 g (0.915 mol) of water (HO), 38 g (0.61 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (Mole ratio: KBM-1003:TEOS = 95:5, HO:EG = 6:4)

[0171] [Comparative Example 8] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 133 g (0.9 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 21 g (0.1 mol) of TEOS (Evonik), 16 g (0.93 mol) of water (HO), 38 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (Mole ratio: KBM-1003:TEOS = 9:1, HO:EG = 6:4)

[0172] Comparative Example 9 A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 119 g (0.8 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 42 g (0.2 mol) of TEOS (Evonik), 17 g (0.96 mol) of water (HO), 40 g (0.64 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 6 hours to prepare a prepolymer. (Mole ratio: KBM-1003:TEOS = 8:2, HO:EG = 6:4)

[0173] [Comparative Example 10] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 104 g (0.7 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 62 g (0.3 mol) of TEOS (Evonik), 18 g (0.99 mol) of water (HO), 41 g (0.66 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 5 hours to prepare a prepolymer. (Mole ratio: KBM-1003:TEOS = 7:3, HO:EG = 6:4)

[0174] [Comparative Example 11] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 133 g (0.895 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 21 g (0.1 mol) of TEOS (Evonik), 3 g (0.005 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The second silane compound was 0.5 mol% of the silane compounds.)

[0175] [Example 1] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 132 g (0.89 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 21 g (0.1 mol) of TEOS (Evonik), 5 g (0.01 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma-Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of the second silane compound, 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane, among the silane compounds was 1.0%).

[0176] [Example 2] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 129 g (0.87 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 21 g (0.1 mol) of TEOS (Evonik), 15 g (0.03 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma-Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of the second silane compound, 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane, among the silane compounds was 3.0%).

[0177] [Example 3] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 126 g (0.85 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 21 g (0.1 mol) of TEOS (Evonik), 26 g (0.05 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma-Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of the second silane compound, 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane, among the silane compounds was 5.0%).

[0178] [Comparative Example 12] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 119 g (0.8 mol) of vinyltrimethoxysilane (Shin-Etsu, KBM-1003), 21 g (0.1 mol) of TEOS (Evonik), 51 g (0.1 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma-Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of the second silane compound, 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane, among the silane compounds was 10%).

[0179] The molar ratios of the components constituting the coating compositions according to Comparative Examples 1 to 12 and Examples 1 to 3, as well as the weight average molecular weights and polydispersity indexes (PDIs) of the prepolymers, are summarized in Table 1.

[0180] [Table 1]

[0181] [Comparative Example 13] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 221 g (0.89 mol) of 3-methacryloxypropyltrimethoxysilane (KBM-503, Shinetsu), 21 g (0.1 mol) of TEOS (Evonik), 5 g (0.01 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma-Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane among the silane compounds was 1%).

[0182] [Comparative Example 14] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 216 g (0.87 mol) of 3-methacryloxypropyltrimethoxysilane (KBM-503, Shinetsu), 21 g (0.1 mol) of TEOS (Evonik), 15 g (0.03 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma-Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma-Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane among the silane compounds was 3%).

[0183] [Comparative Example 15] A coating film (100) was prepared in the same manner as in Comparative Example 1, except that a 500 mL flask was charged with 211 g (0.85 mol) of 3-methacryloxypropyltrimethoxysilane (KBM-503, Shinetsu), 21 g (0.1 mol) of TEOS (Evonik), 26 g (0.05 mol) of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane (Sigma Aldrich), 17 g (0.93 mol) of water (HO), 39 g (0.62 mol) of ethylene glycol (EG, Sigma Aldrich), and 0.1 g of NaOH, and the mixture was stirred at 65°C for 8 hours to prepare a prepolymer. (The molar ratio of 1H,1H,2H,2H-Perfluoro-octyltriethoxysilane among the silane compounds was 5%).

[0184] The molar ratios of the components constituting the coating compositions according to Comparative Examples 12 to 14, and the weight average molecular weights and polydispersity indices (PDIs) of the prepolymers are summarized in Table 2.

[0185] [Table 2]

[0186] [Comparative Example 16] A coating film (100) was prepared in the same manner as in Comparative Example 8, except that 3 wt % of a fluorinated anti-smudge additive, KY-1203 (Shinetsu Co., Ltd.), based on the total weight of the silane compound, was added to the coating composition.

[0187] [Example 4] A coating film (100) was prepared in the same manner as in Example 2, except that 3 wt % of a fluorinated anti-smudge additive, KY-1203 (Shinetsu Co., Ltd.), based on the total weight of the silane compound, was added to the coating composition.

[0188] [Comparative Example 17] A coating film (100) was prepared in the same manner as in Comparative Example 13, except that 3 wt % of a fluorinated anti-smudge additive, KY-1203 (Shinetsu Co., Ltd.), based on the total weight of the silane compound, was added to the coating composition.

[0189] [Measurement example] The coating films prepared in Examples 1 to 4 and Comparative Examples 1 to 17 were evaluated for physical properties according to the following methods, and the results are shown in Table 3 below.

[0190] (1) Water contact angle As shown in Figure 2, a 5 μL water droplet (WD) was dropped onto the surface of the coating layer (120) at a rate of 2.7 μL / sec using a KRUSS MSA (Mobile Surface Analyzer) model, and the angle (θ) between the surface of the coating layer (120) and the boundary of the water droplet (WD) was measured seven times every 0.2 seconds. This measurement was repeated five times, and the average value was taken as the water contact angle.

[0191] In Table 3, the water contact angles are expressed as initial water contact angles.

[0192] (2) Number of scratches A coating film (100) is cut to a size of 100 mm x 50 mm to prepare a coating film sample. The coating film sample is fixed to a flat surface using adhesive tape (3M) with the coating layer (120) facing upward. A 20 mm x 20 mm stainless steel (SUS) jig wrapped with #0000 (LIBERON) nonwoven fabric is then moved back and forth across the surface of the coating layer (120) of the coating film sample at a load of 0.5 kgf and a speed of 45 RPM for 10,000 times, and the number of scratches observed with the naked eye is recorded.

[0193] (3) Water contact angle after scratching A coating film (100) was cut to a size of 100 mm x 50 mm to prepare a coating film sample. The coating film sample was then fixed to a flat surface using adhesive tape (3M) with the coating layer (120) facing upward. A 20 mm x 20 mm stainless steel jig wrapped with #0000 (LIBERON) nonwoven fabric was then slid back and forth across the surface of the coating layer (120) of the coating film sample at a load of 0.5 kgf and a speed of 45 RPM for 10,000 cycles to induce scratches. The water contact angle of the scratched coating film sample was then measured using the method (1) above.

[0194] (4) Water contact angle after eraser wear The coating film (100) is cut to a size of 200 mm x 50 mm to prepare a coating film sample, and the coating film sample is fixed to a flat surface using adhesive tape (3M) so that the coating layer (120) faces upward. Then, a "Manaslu" eraser (an eraser used for abrasion resistance tests) is fixed to a jig and moved back and forth across the surface of the coating layer (120) of the coating film sample at a load of 0.5 kgf and a speed of 45 RPM for 1,000 times (for 1000 seconds), and the water contact angle is measured using the method (1) above.

[0195] (5) Curl The curl is measured by cutting the coating film (100) into a square of 100 mm x 100 mm, placing the coating film sample on a flat glass substrate, and measuring the distance between the corner of the coating film sample and the floor (top) of the glass substrate (see "curl" in Figure 3).

[0196] (6) Crack point radius The coating film (100) is cut to a size of 20mm x 100mm to prepare a coating film sample, and the coating film sample is attached to a bending tester ("Radius Bending Tester") so that the coating layer (120) faces outward as the coating film sample is bent. As the radius of curvature is reduced, the coating film sample is bent, and the radius of curvature at which cracks appear on the coating film sample is measured (see Figure 4).

[0197] [Table 3]

[0198] Referring to Table 3, it can be seen that the coating films (100) according to Examples 1 to 4 have a water contact angle of 100 degrees or more, two or less scratches, a water contact angle after scratching of 98 degrees or more, a water contact angle after eraser abrasion of 95 degrees or more, a curl of 2 mm or less, and a crack point radius of 1 mm or less.

[0199] In addition, it can be confirmed that the difference between the water contact angle and the water contact angle after scratching of the coating film (100) according to Examples 1 to 4 is 10 degrees or less, and the difference between the water contact angle and the water contact angle after abrasion with an eraser is 10 degrees or less.

[0200] As described above, the coating film according to an embodiment of the present invention has a high water contact angle and excellent slip properties, and therefore has excellent contamination prevention and removal properties, as well as excellent scratch resistance and abrasion resistance, and can be used as a cover window or protective film for a flexible display device.

Claims

1. a substrate film; and a coating layer on the substrate film; The coating layer is a water contact angle of 100 degrees or greater; and A water contact angle after scratching of 98 degrees or more, the difference between the water contact angle and the water contact angle after scratching is 8 degrees or less; the coating layer comprises a structural moiety derived from a silane compound and a diol, The silane compound is A first silane compound represented by the following chemical formula 1: A second silane compound represented by the following chemical formula 2: a third silane compound represented by the following formula 3: relative to the total number of moles of the silane compound 80 to 90 mole % of a first silane compound; 1 to 5 mole percent of a second silane compound; and 7 to 15 mole percent of a tertiary silane compound; A coating film comprising: Here, the water contact angle is measured using a 5 μL water droplet (H 2 0) is dropped onto the coating layer, the angle between the surface of the coating layer and the boundary of the water drop, measured; The water contact angle after scratching was measured by cutting the coating film to a size of 100 mm x 50 mm to prepare a coating film sample, fixing the coating film sample to a flat surface using adhesive tape so that the coating layer faced upward, and then moving a 20 mm x 20 mm stainless steel (SUS) jig wrapped with #0000 (LIBERON) nonwoven fabric back and forth over the surface of the coating layer of the coating film sample at a load of 0.5 kgf and a speed of 45 RPM for 10,000 times. [Chemical formula 1] [Chemical formula 2] [Chemical formula 3] Si(OR3)4 R 11 is a substituted or unsubstituted C2 to C5 unsaturated hydrocarbon group, R 12, R 13, and R 14 are each independently a C1 to C5 alkyl group, R 21 is a single bond or a C1 to C4 alkylene group, R 22, R 23, and R 24 are each independently a C1 to C5 alkyl group, m is an integer from 3 to 10, and R 3 is a C1 to C4 alkyl group.

2. 10. The coating film according to claim 1, wherein the coating layer has a water contact angle of 100 to 120 degrees and a water contact angle after scratching of 98 to 110 degrees.

3. 10. The coating film of claim 1, wherein the coating layer has a scratch count of two or less. Here, the number of scratches is the number of scratches observed with the naked eye after preparing a coating film sample by cutting the coating film into a size of 100 mm x 50 mm, fixing the coating film sample on a flat surface with adhesive tape so that the coating layer faces upward, and then using a 20 mm x 20 mm stainless steel (SUS) jig wrapped with #0000 (LIBERON) nonwoven fabric, moving it back and forth across the surface of the coating layer of the coating film sample 10,000 times at a load of 0.5 kgf and a speed of 45 RPM.

4. 2. The coating film of claim 1, wherein the coating layer has a water contact angle after eraser abrasion of 95 degrees or more. The water contact angle after eraser abrasion was measured by cutting the coating film to a size of 200 mm x 50 mm to prepare a coating film sample, fixing the coating film sample to a flat surface with adhesive tape so that the coating layer faced upward, and then fixing a "Manaslu" eraser (an eraser used for abrasion resistance tests) to a jig and moving it back and forth across the coating layer surface of the coating film sample 1,000 times at a load of 0.5 kgf and a speed of 45 RPM.

5. 5. The coating film according to claim 4, wherein the difference between the water contact angle and the water contact angle after the eraser abrasion is 10 degrees or less.

6. 5. The coating film according to claim 4, wherein the coating layer has a water contact angle after eraser abrasion of 95 degrees to 110 degrees.

7. The coating film according to claim 1, having a curl of 2 mm or less based on a coating layer thickness of 10 μm. Here, the curl is defined as the distance between the corner of the coating film sample and the floor of the glass substrate after the coating film sample is placed on a flat glass substrate. The coating film is cut into a square having a size of 100 mm x 100 mm.

8. The coating film according to claim 1, having a crack point radius of 1 mm or less based on a coating layer thickness of 10 μm. Here, the crack point radius is defined as the radius of curvature at which a crack occurs in a coating film sample when the coating film sample is bent as the radius of curvature is reduced, after the coating film sample is prepared by cutting the coating film into a size of 20 mm x 100 mm and the coating film sample is attached to a radius bending tester so that the coating layer faces the outer direction of the bending.

9. a display panel; and 9. The coating film according to claim 1 , disposed on the display panel; A display device comprising:

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