Non-fluorinated silane compound and surface treatment composition comprising same

Abstract

The present invention provides a non-fluorinated silane compound and a surface treatment composition comprising same. The non-fluorinated silane compound according to the present invention can not only increase an initial contact angle but also enhance wear resistance. Therefore, the non-fluorinated silane compound according to the present invention can be advantageously used as a surface treatment agent such as an antifouling coating agent or a water-repellent coating agent.

Description

Non-fluorinated silane compound and surface treatment composition containing the same

[0001] The present invention relates to a non-fluorinated silane compound and a surface treatment composition containing the same, and more specifically, to a non-fluorinated silane compound and a surface treatment composition containing the same that can be advantageously used as a surface treatment agent by not only increasing the initial contact angle but also improving wear resistance.

[0002] Fluorine-containing silane compounds are known to provide excellent water repellency, oil repellency, and antifouling properties when used for surface treatment of substrates. A layer obtained from a surface treatment composition containing a fluorine-containing silane compound can be applied to various substrates, such as glass, plastics, fibers, and building materials.

[0003] For example, Korean registered patent No. 10-0967981 discloses a fluorine-containing silane compound having a perfluoropolyether group in the molecular main chain and a hydrolyzable group bonded to a Si atom at the molecular end or terminal end.

[0004] However, research results have been published stating that perfluorinated chemicals (PFCs), such as these fluorine-containing silane compounds, are toxic substances that do not decompose in the human body and accumulate gradually, causing liver damage and cancer. Furthermore, in Europe and the United States, there are discussions acknowledging the harmfulness of perfluorinated chemicals and regulating their use.

[0005] Accordingly, research on non-fluorinated antifouling agents or water-repellent agents is being conducted.

[0006] However, non-fluorinated antifouling agents or water repellents have the problem of insufficient wear resistance. In particular, polysiloxane-based antifouling agents or water repellents lack wear resistance due to the flexibility of Si-O-Si bonds.

[0007] Therefore, there is a need for the development of non-fluorinated antifouling or water-repellent agents that can be advantageously used as surface treatment agents by not only increasing the initial contact angle but also improving wear resistance.

[0008] One objective of the present invention is to provide a non-fluorinated silane compound capable of not only increasing the initial contact angle but also improving wear resistance.

[0009] Another objective of the present invention is to provide a surface treatment composition comprising the silane compound.

[0010] Another objective of the present invention is to provide a coating film formed using the surface treatment composition.

[0011] Another objective of the present invention is to provide an optical member and an image display device comprising the above-mentioned coating film.

[0012] On the other hand, the present invention provides a compound represented by the following chemical formula 1.

[0013] [Chemical Formula 1]

[0014]

[0015] In the above formula,

[0016] R 1 is a C1-C4 alkoxy group, and

[0017] R 2 and R 3 Each is independently a hydrogen atom, a halogen atom, a C1-C6 alkyl group, or a C1-C4 alkoxy group, and

[0018] L is or And,

[0019] R 4 is C4-C 22 It is an alkylene group of, and

[0020] R 5 is C4-C 22 It is an alkyl group.

[0021]

[0022] In one embodiment of the present invention, R 1 It can be a methoxy group.

[0023] In one embodiment of the present invention, R 2 and R 3 Each can be an independent C1-C4 alkoxy group.

[0024] In one embodiment of the present invention, R 4 is C4-C 15 It is an alkylene group of, and R 5 is C 10 -C 20 It can be an alkyl group.

[0025] A compound according to one embodiment of the present invention may be a compound represented by any one of the following chemical formulas 1-1 to 1-3.

[0026] [Chemical Formula 1-1]

[0027]

[0028] [Chemical Formula 1-2]

[0029]

[0030] [Chemical Formula 1-3]

[0031]

[0032]

[0033] On the other hand, the present invention provides a surface treatment composition comprising the above compound.

[0034] A surface treatment composition according to one embodiment of the present invention may additionally include one or more selected from the group consisting of solvents, catalysts, and additives.

[0035] A surface treatment composition according to one embodiment of the present invention can be used as an antifouling coating agent or a water-repellent coating agent.

[0036]

[0037] On the other hand, the present invention provides a coating film formed using the above-mentioned surface treatment composition.

[0038] On the other hand, the present invention provides an optical member comprising the above-mentioned coating film.

[0039] On the other hand, the present invention provides an image display device comprising the above-mentioned coating film.

[0040] The long-chain alkyl group-containing silane compound having an ester structure according to the present invention can not only increase the initial contact angle but also improve wear resistance. Therefore, the long-chain alkyl group-containing silane compound having an ester structure according to the present invention can be advantageously used as a surface treatment agent, such as an antifouling coating agent or a water-repellent coating agent.

[0041] The present invention will be described in more detail below.

[0042]

[0043] One embodiment of the present invention relates to a compound represented by the following chemical formula 1.

[0044] [Chemical Formula 1]

[0045]

[0046] In the above formula,

[0047] R 1 is a C1-C4 alkoxy group, and

[0048] R 2 and R 3 Each is independently a hydrogen atom, a halogen atom, a C1-C6 alkyl group, or a C1-C4 alkoxy group, and

[0049] L is or And,

[0050] R 4 is C4-C 22 It is an alkylene group of, and

[0051] R 5 is C4-C 22 It is an alkyl group.

[0052]

[0053] As used in this specification, C1-C4 alkoxy groups refer to straight-chain or branched alkoxy groups composed of 1 to 4 carbon atoms, and include but are not limited to methoxy, ethoxy, n-propanoxy, etc.

[0054] As used in this specification, C1-C6 alkyl groups refer to straight-chain or branched monovalent hydrocarbons having 1 to 6 carbon atoms, and include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, n-hexyl, etc.

[0055] C4-C used in this specification 22 The alkylene group refers to a straight-chain or branched divalent hydrocarbon composed of 4 to 22 carbon atoms, and includes, but is not limited to, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, tridecylene, tetradecylene, pentadecylene, hexadecylene, heptadecylene, stearylene, nonadecylene, eicosanylene, etc.

[0056] C4-C used in this specification 22 The alkyl group refers to a straight-chain or branched hydrocarbon composed of 4 to 22 carbon atoms, and includes, but is not limited to, pentyl, hexyl, 2-ethylhexyl, heptyl, 2-ethylheptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, stearyl, nonadecyl, eicosanyl, etc.

[0057]

[0058] In one embodiment of the present invention, R in terms of improving adhesion to the substrate, wear resistance, and reactivity with the substrate 1 It can be a methoxy group.

[0059] In one embodiment of the present invention, R in terms of improving adhesion to the substrate, wear resistance, and reactivity with the substrate 2 and R 3Each can be an independent C1-C4 alkoxy group.

[0060] In one embodiment of the present invention, R in terms of water repellency, antifouling properties, wear resistance, improved solubility, and ease of synthesis 4 is C4-C 15 It is an alkylene group of, and R 5 is C 10 -C 20 It can be an alkyl group.

[0061] Preferably, R in terms of improved water repellency, antifouling properties, abrasion resistance, and solubility, and ease of synthesis. 4 is C 10 -C 15 It is an alkylene group of, and R 5 is C 15 -C 20 It can be an alkyl group.

[0062] In particular, a compound according to one embodiment of the present invention may be a compound represented by any one of the following chemical formulas 1-1 to 1-3.

[0063] [Chemical Formula 1-1]

[0064]

[0065] [Chemical Formula 1-2]

[0066]

[0067] [Chemical Formula 1-3]

[0068]

[0069]

[0070] The compound represented by the above chemical formula 1 can be prepared by methods known in the art.

[0071] Specifically, the compound represented by Chemical Formula 1 of the present invention can be prepared by the method described in the synthesis example below.

[0072]

[0073] The compound represented by Chemical Formula 1 above has a structure in which a long-chain alkylene group and a long-chain alkyl group are bonded via an ester group, and has a three-dimensional structure in which the long-chain alkylene group and the long-chain alkyl group are bent at the ester group portion. Accordingly, when the compound represented by Chemical Formula 1 above is used as a surface treatment agent, it can not only increase the initial contact angle but also improve wear resistance.

[0074] In addition, the compound represented by the above chemical formula 1 can ensure adhesion to the substrate due to the terminal alkoxysilane structure and can also improve wear resistance.

[0075] In addition, the compound represented by the above chemical formula 1 is environmentally friendly because it does not contain fluorine.

[0076]

[0077] Accordingly, one embodiment of the present invention relates to a surface treatment composition comprising a compound represented by the above chemical formula 1.

[0078] The compound represented by the above chemical formula 1 may be included in an amount of 0.1 to 40 weight%, preferably 1 to 10 weight%, based on 100 weight% of the total surface treatment composition. If the compound represented by the above chemical formula 1 is included in an amount less than the above range based on 100 weight% of the total surface treatment composition, water repellency and antifouling properties may be reduced, and if it is included in an amount greater than the above range, durability may be reduced.

[0079] A surface treatment composition according to one embodiment of the present invention may additionally include one or more selected from the group consisting of solvents, catalysts, and additives.

[0080] The above solvents include alcohol-based (methanol, ethanol, isopropanol, butanol, methylcellosolve, ethylcellosolve, etc.), ketone-based (methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone, cyclohexanone, etc.), acetate-based (ethyl acetate, propyl acetate, normal butyl acetate, tertiary butyl acetate, methylcellosolve acetate, ethylcellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methoxybutyl acetate, methoxypentyl acetate, etc.), hexane-based (hexane, heptane, octane, etc.), benzene-based (benzene, toluene, xylene, etc.), and ether-based (diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, etc.) may be preferably used. In terms of solubility, toluene may be particularly used as the solvent. Each of the solvents exemplified above may be used alone or in combination of two or more.

[0081] As the additional component mentioned above, an acid, a base, a transition metal, or a metal-based catalyst containing a transition metal may be used as the catalyst.

[0082] Examples of the above acids include acetic acid, trifluoroacetic acid, etc., and examples of the above bases include ammonia, triethylamine, diethylamine, etc. In addition, examples of the above transition metals include titanium (Ti), nickel (Ni), tin (Sn), platinum (Pt), ruthenium (Ru), rhodium (Rh), etc., and examples of metal-based catalysts containing the above transition metals include tetrapropyl titanate, tetrapropyl zirconate, etc.

[0083] Examples of the above additives include silicone oil, aliphatic hydrocarbons, etc.

[0084] The above silicone oil is a non-reactive silicone compound. The above silicone oil serves to improve surface lubricity.

[0085] The above silicone oil may be a linear or cyclic silicone oil having 2,000 or fewer siloxane bonds.

[0086] Examples of the above straight-chain silicone oils include dimethyl silicone oil, methylphenyl silicone oil, methylhydrogen silicone oil, etc. The above straight-chain silicone oil may be modified by alkyl, aralkyl, polyether, higher fatty acid ester, fluoroalkyl, amino, epoxy, carboxyl, alcohol, etc.

[0087] Examples of the above-mentioned cyclic silicone oil include cyclic dimethylsiloxane oil.

[0088] The above-mentioned aliphatic hydrocarbons play a role in improving water repellency and antifouling properties.

[0089] Examples of the above-mentioned aliphatic hydrocarbons include alkanes such as octane, dodecane, and hexadecane, and terpenes such as limonene.

[0090]

[0091] A surface treatment composition according to one embodiment of the present invention exhibits water repellency, oil repellency, antifouling properties, surface lubricity, and wear resistance, so it can be used as an antifouling coating agent or a water-repellent coating agent.

[0092] A surface treatment composition according to one embodiment of the present invention can be applied to a wet coating method or a dry coating method.

[0093] Wet coating methods include immersion coating, spin coating, flow coating, spray coating, roll coating, gravure coating, etc., while dry coating methods include deposition (typically vacuum deposition), sputtering, CVD, etc. Specific examples of deposition methods (typically vacuum deposition) include resistance heating, electron beams, high-frequency heating using microwaves, ion beams, etc. Specific examples of CVD methods include plasma CVD, optical CVD, thermal CVD, etc. In addition, coating by atmospheric pressure plasma is also possible.

[0094] When a surface treatment composition according to one embodiment of the present invention is applied by a wet coating method, it necessarily includes a solvent, and when applied by a dry coating method, it may or may not include a solvent.

[0095]

[0096] One embodiment of the present invention relates to a coating film formed using the surface treatment composition described above.

[0097] In addition, one embodiment of the present invention relates to an optical member or image display device comprising the above-mentioned coating film.

[0098] A method for forming a coating film of a surface treatment composition according to the present invention comprises the step of applying the surface treatment composition onto a substrate using the wet coating method or dry coating method described above, and optionally the step of post-treating the applied surface treatment composition.

[0099] The above description may be composed of materials such as, for example, glass, resin, metal, ceramic, semiconductor, fiber, fur, leather, wood, stone, etc.

[0100] The glass is preferably sapphire glass, soda-lime glass, alkali aluminosilicate glass, borosilicate glass, alkali-free glass, crystal glass, or quartz glass, and chemically strengthened soda-lime glass, chemically strengthened alkali aluminosilicate glass, and chemically bonded borosilicate glass are particularly preferred. The resin may be a natural or synthetic resin, such as acrylic resin or polycarbonate. The metal may be aluminum, copper, iron, or an alloy thereof, and the semiconductor may be silicon, germanium, etc.

[0101] The above post-treatment may involve supplying moisture and / or drying and heating sequentially or simultaneously.

[0102] The method of supplying moisture may be condensation caused by the temperature difference between the substrate and the surrounding atmosphere, or steam spraying. The above moisture supply can be carried out under an atmosphere of 0 to 250°C, preferably 60°C or higher, more preferably 100°C or higher, and even more preferably 100 to 180°C. By supplying moisture within this temperature range, it is possible to carry out hydrolysis. The pressure at this time is not particularly limited, but can be performed at atmospheric pressure.

[0103] The above drying heating can be carried out by heating under a drying atmosphere exceeding 60°C. The above drying heating can preferably be performed by placing under an atmosphere of unsaturated water vapor pressure at a temperature exceeding 90°C, for example, 100 to 250°C. The pressure at this time is not particularly limited, but can be performed at atmospheric pressure.

[0104] The above moisture supply and drying heating can be performed continuously by using superheated steam.

[0105] The thickness of the above coating film is not particularly limited, but in terms of optical performance, surface lubricity, wear resistance and / or antifouling properties, it may be 1 to 30 nm, preferably 1 to 15 nm, and more preferably 1 to 10 nm.

[0106] The above optical member may be, for example, a front or rear protective plate, anti-reflective plate, polarizing plate, or anti-glare plate of an image display device; a touch panel sheet or cover window of a device such as a mobile phone or portable information terminal; a disc surface of an optical disc such as a Blu-ray disc, DVD disc, CD-R, or MO; an optical fiber; a lens such as a pair of glasses; an interior or exterior material for an automobile; a mirror and glass, etc.

[0107] The above image display device may be, for example, a liquid crystal display (LCD), an electroluminescent display (EL), a plasma display (PDP), a field emission display (FED), an organic light-emitting diode (OLED), etc.

[0108]

[0109] The present invention will be explained more specifically below through examples, comparative examples, and experimental examples. These examples, comparative examples, and experimental examples are intended solely to illustrate the present invention, and it is obvious to those skilled in the art that the scope of the present invention is not limited thereto.

[0110]

[0111] Synthesis Example 1: Synthesis of a compound represented by Chemical Formula 1-1

[0112] [Chemical Formula 1-1]

[0113]

[0114] 10 g of icosan-1-ol, 6.17 g of 10-undecenoic acid, 0.64 g of p-toluenesulfonic acid, and 200 mL of toluene were added to a 250 mL reactor. The reaction mixture was reacted at 130 °C for 24 hours, after which the temperature was lowered to room temperature. Water and ethyl acetate were added to the reaction mixture. Subsequently, phase separation was performed to separate the mixture into an organic layer and a water layer, after which magnesium sulfate was added to the separated organic layer. The mixture was filtered and concentrated. The concentrate was vacuum dried to obtain 14 g of icosyl undek-10-enoate (yield: 90%).

[0115] 14 g of icosil undek-10-enoate, 30 mL of trimethoxysilane, and 0.01 g of platinum (Pt) catalyst were added to a 100 mL pressurized reactor. The reaction mixture was reacted at 90°C for 48 hours, after which the temperature was lowered to room temperature. The reaction mixture was filtered and concentrated. The concentrate was vacuum dried to obtain 15 g of the title compound (purity: 65.1%, yield: 84.8%).

[0116] (Mass Spectrometry) Ionization Mode = ESI+: m / z = 558.47 [M+H] +

[0117]

[0118] Synthesis Example 2: Synthesis of a compound represented by Chemical Formula 1-2

[0119] [Chemical Formula 1-2]

[0120]

[0121] 10 g of icosan-1-ol, 3.69 g of 4-pentenoic acid, 0.64 g of p-toluenesulfonic acid, and 150 mL of toluene were added to a 250 mL reactor. The reaction mixture was reacted at 130 °C for 24 hours, after which the temperature was lowered to room temperature. Water and ethyl acetate were added to the reaction mixture. Subsequently, phase separation was performed to separate the mixture into an organic layer and a water layer, after which magnesium sulfate was added to the separated organic layer. The mixture was filtered and concentrated. The concentrate was vacuum dried to obtain 11 g of icosyl pent-4-enoate (yield: 86.3%).

[0122] 11 g of icosyl pent-4-enoate, 50 mL of trimethoxysilane, and 0.01 g of platinum (Pt) catalyst were added to a 100 mL pressurized reactor. The reaction mixture was reacted at 90°C for 24 hours, after which the temperature was lowered to room temperature. The reaction mixture was filtered and concentrated. The concentrate was vacuum dried to obtain 13 g of the title compound (purity: 87.5%, yield: 89.5%).

[0123] (Mass Spectrometry) Ionization Mode = ESI+: m / z = 502.41 [M+H] +

[0124]

[0125] Synthesis Example 3: Synthesis of a compound represented by Chemical Formula 1-3

[0126] [Chemical Formula 1-3]

[0127]

[0128] 10 g of 1-decanol, 12.8 g of 10-undecenoic acid, 1.2 g of p-toluenesulfonic acid, and 200 mL of toluene were added to a 250 mL reactor. The reaction mixture was reacted at 130 °C for 24 hours, after which the temperature was lowered to room temperature. Water and ethyl acetate were added to the reaction mixture. Subsequently, phase separation was performed to separate the organic layer and the water layer, and magnesium sulfate was added to the separated organic layer. The mixture was filtered and concentrated. The concentrate was vacuum dried to obtain 18.5 g of decyl undec-10-enoate (yield: 90.2%).

[0129] 18.5 g of decyl undek-10-enoate, 50 mL of trimethoxysilane, and 0.01 g of platinum (Pt) catalyst were added to a 100 mL pressurized reactor. The reaction mixture was reacted at 90°C for 24 hours, after which the temperature was lowered to room temperature. The reaction mixture was filtered and concentrated. The concentrate was vacuum dried to obtain 25 g of the title compound (purity: 90.3%, yield: 98.4%).

[0130] (Mass Spectrometry) Ionization Mode = ESI+: m / z = 446.34 [M+H] +

[0131]

[0132] Example 1

[0133] Surface treatment agent 1 was prepared by dissolving the compound represented by Chemical Formula 1-1 obtained in Synthesis Example 1 above in toluene to a concentration of 5 wt%. Surface treatment agent 1 prepared above was applied onto a glass substrate by a spin coating method, and then a surface treatment layer was formed by drying after moisture treatment at 100°C.

[0134]

[0135] Example 2

[0136] A surface treatment layer was formed by performing the same procedure as in Example 1, except that the compound represented by Chemical Formula 1-2 obtained in Synthesis Example 2 was used instead of the compound represented by Chemical Formula 1-1.

[0137]

[0138] Example 3

[0139] A surface treatment layer was formed by performing the same procedure as in Example 1, except that the compound represented by Chemical Formula 1-3 obtained in Synthesis Example 3 was used instead of the compound represented by Chemical Formula 1-1.

[0140]

[0141] Comparative Example 1

[0142] A surface treatment layer was formed by performing the same procedure as in Example 1 above, except that a compound represented by the following chemical formula a was used instead of the compound represented by chemical formula 1-1, and ethyl acetate was used instead of toluene.

[0143] [Chemical formula a]

[0144]

[0145]

[0146] Comparative Example 2

[0147] A surface treatment layer was formed by performing the same procedure as in Example 1 above, except that a compound represented by the following chemical formula b was used instead of the compound represented by chemical formula 1-1, and ethyl acetate was used instead of toluene.

[0148] [Chemical formula b]

[0149]

[0150]

[0151] Comparative Example 3

[0152] A surface treatment layer was formed by performing the same procedure as in Example 1 above, except that a compound represented by the following chemical formula c was used instead of the compound represented by chemical formula 1-1.

[0153] [Chemical formula c]

[0154]

[0155]

[0156] Experimental Example 1:

[0157] The static contact angle of water was measured for the surface treatment layer formed in the above examples and comparative examples. The static contact angle of water was measured using a contact angle measuring device (manufactured by Kyowa Kaimen Kagaku Co., Ltd.) with 3 μL of water.

[0158] First, as an initial evaluation, the static contact angle of water was measured after the surface treatment layer was formed, with nothing yet in contact with the surface (zero friction cycles). Subsequently, as an evaluation of frictional durability, a steel wool frictional durability evaluation was conducted. Specifically, the substrate with the surface treatment layer formed was placed horizontally, and steel wool (count #0000, dimensions 5 mm × 20 mm × 20 mm) was brought into contact with the exposed upper surface of the surface treatment layer. A load of 2,000 gf was applied thereto, and then the steel wool was reciprocated at a speed of 100 mm / second while the load was applied. The static contact angle of water (degrees) was measured for the number of reciprocations listed in Table 1 below. The results are shown in Table 1 below.

[0159]

[0160] Wear count (times) Contact angle (degrees) Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3095.682.589.179.493.890.9100096.183.191.269.899.692.6200095.782.889.377.187.486.4300094.882.989.870.877.782.6500094.383.890.165.177.678.9700095.582.491.564.873.875.6900095.181.590.764.170.675.31100096.180.992.063.569.670.5

[0161]

[0162] Through Table 1 above, it can be confirmed that the surface treatment layers of Examples 1 to 3, which are surface-treated with a compound represented by Chemical Formula 1, not only have a high initial contact angle, but also exhibit superior wear resistance compared to the surface treatment layers of Comparative Examples 1 to 3, which are surface-treated with a silane compound of a different structure that does not have an ester structure instead of the compound represented by Chemical Formula 1.

[0163]

[0164] As specific parts of the present invention have been described in detail above, it is evident to those skilled in the art that such specific descriptions are merely preferred embodiments and do not limit the scope of the present invention. Those skilled in the art will be able to make various applications and modifications within the scope of the present invention based on the above description.

[0165] Accordingly, the substantial scope of the present invention shall be defined by the appended claims and their equivalents.

Claims

1. Compound represented by the following chemical formula 1: [Chemical Formula 1] In the above formula, R 1 is a C1-C4 alkoxy group, and R 2 and R 3 Each is independently a hydrogen atom, a halogen atom, a C1-C6 alkyl group, or a C1-C4 alkoxy group, and L is or And, R 4 is C4-C 22 It is an alkylene group of, and R 5 is C4-C 22 It is an alkyl group.

2. In Paragraph 1, R 1 A compound that is a methoxy group.

3. In Paragraph 1, R 2 and R 3 Each is a compound that is independently a C1-C4 alkoxy group.

4. In Paragraph 1, R 4 is C4-C 15 It is an alkylene group of, and R 5 is C 10 -C 20 A compound that is an alkyl group of 5. In claim 1, a compound represented by any one of the following chemical formulas 1-1 to 1-3: [Chemical Formula 1-1] [Chemical Formula 1-2] [Chemical Formula 1-3] 6. A surface treatment composition comprising a compound according to any one of claims 1 to 5.

7. A surface treatment composition according to claim 6, further comprising one or more selected from the group consisting of solvents, catalysts, and additives.

8. A surface treatment composition used as an antifouling coating agent or a water-repellent coating agent in claim 6.

9. A coating film formed using a surface treatment composition according to paragraph 6.

10. An optical member comprising a coating film according to paragraph 9.

11. An image display device comprising a coating film according to paragraph 9.

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