KR20010002162A - Coating composition and preparation method thereof - Google Patents

Abstract

PURPOSE: A coating composition having pollution preventing, water drop formation preventing and anti-fogging function and obtained by copolymerization of a gamma-methacryloxypropyltrialkoxysilane monomer and N-vinylpyrrolidone and hydrolyzing is provided, which can prevent the surface injury of glass. CONSTITUTION: A gamma-methacryloxypropyltrialkoxysilane monomer and N-vinylpyrrolidone are copolymerized in a ratio of 30 to 70 to 70 : 30 to give a polymer, which is hydrolyzed to give a coating composition containing a hydrophilic polymer. The coating composition comprises 1 to 6% by weight of the hydrophilic polymer and 90 to 97% by weight of water and/or an organic solvent such as methyl alcohol, ethyl alcohol or mixture thereof.

Description

Coating composition and preparation method thereof {COATING COMPOSITION AND PREPARATION METHOD THEREOF}

The present invention relates to a coating composition and a method for manufacturing the same, and in particular, the coating on the glass surface to give a function such as anti-pollution, water droplet prevention and anti-fog, thereby preventing glass damage coating composition And to a method for producing the same.

Glass, which is widely used in real life, is typically used for mirrors, car windows, building windows, etc., which are required to be clean and transparent without exception. However, in places where water is heavily used, such as public baths, salt, iron, and / or oil contained in the water may cause contamination of the glass surface, which may cause damage to the glass surface and ultimately lose transparency. Let's do it. Therefore, there is a need to prevent continuous contamination by periodically cleaning the glass surface. That is, there is a need for a glass cleaner that is excellent in cleaning power and has a relatively long antifouling effect after cleaning.

The principle of pollution prevention provided by the cleaning agent is as follows. The cleaner applied to the glass surface forms a thin film, which prevents direct contact between the water and the glass surface. That is, since the glass surface is not in contact with water, it is possible to prevent contamination by water. As a result, if the coated coating can be maintained for a relatively long time, since contamination of the glass surface can be prevented for a long time, a coating composition for forming the coating for a long time is required. In addition, the coated coating film should be free of heterogeneity and have commercial value by having anti-fog and water droplet generation.

Such glass cleaners are generally prepared by diluting the surfactant in water. In addition to the cleaning function, it has the function of preventing the formation of water droplets and antifogging. However, there is a problem that the surfactant coating film produced by applying such a glass cleaner is easily peeled off when water, such as a shower stream. When water comes in contact with the coating film, the coating film immediately melts, so that water is directly in contact with the glass surface within a short time. As a result, in this case, contamination and damage of the glass surface cannot be prevented.

In order to improve this disadvantage, the application of hydrophobic resin on the glass surface can prevent the glass surface from being damaged because it is not easily removed by water. However, glass, especially mirrors, can be prevented due to problems such as fog, formation of water droplets, and deterioration of transparency. It cannot be maintained as a function. If the membrane is coated with a hydrophilic resin that has good adhesion to the glass surface and has a hydrophilic property to prevent water from being washed off easily, it will be possible to prevent damage to the glass surface while maintaining anti-fog and water droplet generation. will be.

US Pat. No. 4,098,840 to Yoshida et al., Dated July 4, 1978, and US Pat. No. 4,522,966, issued to Funaki et al., Dated January 11, 1985. A synthetic coating composition is disclosed which can form a coating film having an anti-fog function by using an alkoxysilane compound as a bond reinforcing agent and mixing a hydrophilic polymer and heat curing. However, the coating coating film prepared using such a coating composition is weak in durability, and when the function is degraded, there is a disadvantage that it cannot be easily removed. In addition, EP 0,620,255 A1 improves durability by forming a coating film using a copolymer of an organic alkoxysilane compound and a hydrophilic monomer. However, even in this case, there is a limit in durability, and when the function is deteriorated, there is a disadvantage in that it cannot be easily removed.

The present invention has been made in view of the above-described problems, and an object of the present invention is to have a detergency and to prevent the coating coating film from being easily dissolved in water. It is to provide a coating composition.

Another object of the present invention is to provide a method for producing a coating composition having excellent performance as described above.

In order to achieve the above object, the present invention provides a coating composition comprising a hydrophilic polymer obtained by hydrolyzing a copolymer obtained by copolymerizing a gamma-methacryloxypropyltrialkoxysilane monomer and an N-vinylpyrrolidone monomer (of the alkoxy group) Carbon number is 1 to 2).

In particular, the amount of the gamma-methacryloxypropyltrialkoxysilane and the N-vinylpyrrolidone is preferably 30:70 to 70:30 by weight.

The coating composition also preferably consists of about 1-6% by weight of the hydrophilic polymer and water and / or an organic solvent having an optional composition ratio with respect to 100% by weight of the coating composition. As the organic solvent, methyl alcohol and / or ethyl alcohol can be easily used.

More preferably, the hydrophilic monomer obtained by hydrolyzing about 2 parts by weight or less of gamma-methacryloxypropyltrialkoxysilane with respect to 100 parts by weight of the coating composition is to further improve the antifogging function.

In addition, the coating composition may further comprise 0.1 to 1.0 parts by weight of colloidal silica with respect to 100 parts by weight as a wear agent to improve the cleaning power.

The hydrophilic polymer obtained by the copolymerization includes various unit copolymerized polymer compounds, and mixtures thereof may also be used. That is, at least one polymer selected from the group consisting of the unit copolymerized polymer compound may be used.

Another object of the present invention described above is to copolymerize a gamma-methacryloxypropyltrialkoxysilane monomer and an N-vinylpyrrolidone monomer to prepare a copolymer thereof;

Hydrolyzing the copolymer in water and an organic solvent; And

Dilution of the hydrolyzate with water and / or an organic solvent is achieved by a process for producing a coating composition (the alkoxy group has 1 to 2 carbon atoms).

Especially as the organic solvent, methyl alcohol, ethyl alcohol and mixtures thereof can be preferably used.

Also preferably, the copolymerization process may be performed under a nitrogen atmosphere at a temperature of about 70 ° C. for about 5 hours, and the hydrolysis process may be performed at about 60 ° C. for about 10 hours.

According to the present invention, 1-5% by weight of a hydrophilic polymer obtained by hydrolyzing a copolymer obtained by copolymerizing a gamma-methacryloxypropyltrialkoxysilane monomer and an N-vinylpyrrolidone monomer is water and / or organic Coating of the coating composition obtained by dilution in a solvent onto the glass surface prevents contamination of the glass and maintains its transparency continuously.

The coating composition of the present invention described above can be applied to not only glass, but also metal, synthetic resin and the like for the purpose of explanation.

A very thin coating can be formed on the surface of the glass by synthesizing a hydrophilic polymer with adhesion to the glass surface and diluting it and applying it to the glass surface in the form of a coating composition. The coating composition prepared by the above method can be easily applied onto the glass surface and dried within 5 minutes after coating without additional heating to form a coating film and to prevent water droplet generation and anti-fog.

Hereinafter, the working principle of the coating composition of the present invention and a manufacturing method thereof will be described.

The N-vinylpyrrolidone monomer used to synthesize the hydrophilic polymer (A) having adhesion to the glass surface has a basic function in showing the function of preventing the formation of water droplets. This presumption can be deduced from the fact that the coating film made of polyvinylpyrrolidone is excellent in preventing the formation of water droplets. However, when the polyvinylpyrrolidone, which is a kind of hydrophilic polymer, is diluted with water or a solvent alone and is applied very thinly, it shows a function of preventing the formation of water droplets, but if it is sprayed only a few times on top of it, it is immediately washed out. .

By the way, an air obtained by copolymerizing a gamma-methacryloxypropyltrialkoxy silane containing a gamma-methacryloxypropyltrimethoxysilane monomer or a gamma-methacryloxypropyltriethoxysilane monomer with an N-vinylpyrrolidone monomer Hydrolysis of the copolymer (B) produces silanol functional groups, which induce adhesion to the glass surface and at the same time induce reticular bonding of the coating resin. This prevents the hydrophilic polymer (A) from easily dissolving and disappearing in water. Various methods may be applied to the copolymerization process, but the present inventors performed by performing about 4 to 6 hours, especially 5 hours under a nitrogen atmosphere at a temperature of about 60 to 80, especially 70 ° C.

In addition, various methods may be applied to the hydrolysis process. The inventors carried out by adding and heating pure and organic solvents, preferably methyl alcohol, without a separate catalyst. In the hydrolysis of the copolymer (B), addition of a catalyst such as an acid, a base catalyst, or a metal salt may generate solids during hydrolysis. The hydrolysis is allowed to take place at about 50-70 ° C., preferably at 60 ° C., without catalyst, for about 8-12 hours, preferably 10 hours.

When only copolymer (B) is diluted in a solvent and applied to the glass surface in the form of a coating composition and dried, hydrophobicity cannot be obtained, and thus a function of preventing water droplets cannot be obtained. However, the hydrolyzed hydrophilic polymer (A), that is, a polymer obtained by hydrolyzing a copolymer (B) of a gamma-methacryloxypropyltrialkoxysilane monomer and an N-vinylpyrrolidone monomer, is applied to a glass surface and then dried. It represents the prevention of water generation and anti-fog.

The resulting hydrophilic polymer (A) is diluted with water or an organic solvent and used in the form of a coating composition. As the organic solvent, polar ones are easily used, such as methyl alcohol, ethyl alcohol, isopropyl alcohol, dioxane, cellosolve, and the like. For the convenience of construction, the hydrophilic polymer (A) is preferably diluted with a mixture of two or more of water, methyl alcohol and ethyl alcohol. The coating composition thus prepared is buried in a tissue or soft cloth, and then thinly applied to the glass surface and left to dry within 5 minutes to exert the effect.

When copolymerizing the gamma-methacryloxypropyltrialkoxysilane monomer and the N-vinylpyrrolidone monomer, the amount thereof is preferably 30:70 to 70:30 by weight. If the amount of the gamma-methacryloxypropyltrialkoxysilane monomer is less than 30% by weight, it is not preferable because the coating film can be easily washed off by water. If the amount of the gamma-methacryloxypropyltrialkoxysilane monomer is less than 70% by weight, the coating film becomes hydrophobic and prevents the formation of water droplets. Since this may be lowered, their amount used is in the above range.

Colloidal silica can be added to the coating composition as a cleaning aid to take advantage of the function of the colloidal silica as a wear agent. Colloidal silica wears dirt off the glass surface, which improves the cleaning power. The addition amount thereof is 0.1 to 1.0 parts by weight based on 100 parts by weight of the coating composition. This is because if the amount thereof is less than 0.1 part by weight, it is not preferable because the wear performance cannot be sufficiently obtained to obtain an effect of increasing the cleaning power, and if the amount thereof is more than 1.0 part by weight, the effect is not increased.

In addition, a hydrophilic monomer (C) product obtained by hydrolyzing gamma-glycidoxypropyltrimethoxysilane alone may be added as an adjuvant to the coating composition. Gamma-glycidoxypropyltrimethoxysilane has no anti-fog and anti-fog generation function, but the hydrophilic monomer hydrolyzed to this shows anti-fog and anti-fog generation. However, the effect is temporary and will soon be washed away.

On the other hand, when the hydrophilic monomer (C), which is a hydrolysis product of gamma-glycidoxypropyltrimethoxysilane, is used together with the hydrophilic polymer (A), the antifogging function is improved than when the hydrophilic polymer (A) is used alone. You can. Its addition amount is to be 2 parts by weight or less based on 100 parts by weight of the coating composition. If the addition amount exceeds 2 parts by weight, the coating amount may become opaque after the coating composition is applied and dried, so that the addition amount thereof is in the above-described range.

Hereinafter, the present invention will be described in detail through specific synthesis examples and examples, but the present invention is not limited thereto. In order to identify the compounds obtained in each synthesis example, chemical shifts were examined using 300 MHz (Varian) as a nuclear magnetic resonance spectroscopy equipment.

Synthesis Example 1

Synthesis of N-vinylpyrrolidone and gamma-methacryloxypropyltrimethoxysilane copolymer (copolymer B1)

70 g of N-vinylpyrrolidone, 30 g of gamma-methacryloxypropyltrimethoxysilane, 0.2 g of azobisbutyronitrile and 400 g of isopropyl alcohol were added to a reaction tank equipped with a mechanical stirrer, and the stirring speed was 400 rpm in a nitrogen atmosphere. Stirred to completely dissolve all reactions. The reaction was then heated to 70 ℃ to react for 5 hours. After 5 hours the reaction was cooled to terminate the reaction. The viscosity of the obtained reactants was 2000 cps (using a Brookfield viscometer). The reaction product was reprecipitated in water to give a white solid. The chemical shift of each of the hydrogen atoms of the copolymer obtained using nuclear magnetic resonance spectroscopy was investigated.

Yield: 60 g (60%)

¹ HNMR (CCl ₄ ): ?? (ppm), 1.0-1.1 (d, 3H, CH ₃ ), 2.9-3.3 (m, 2H, CH ₂ ), 3.5 (s, 3H, -OCH ₃ )

GPC (DMF): M _n = 34,000, M _w = 104,000

Looking at the nuclear magnetic resonance spectroscopy data, it can be seen that gamma-methacryloxypropyltrimethoxysilane participated in the polymerization from a doublet proton peak for methyl group between 1.0-1.1 ppm chemical shift. From the broad proton peak of pyrrolidone ring methylene hydrogen appearing between 2.9-3.3 ppm, it can be seen that N-vinylpyrrolidone participated in the polymerization. It can also be seen that the gamma-methacryloxypropyltrimethoxysilane was not hydrolyzed from a single ppm proton peak for methoxy group of 3.5 ppm.

Synthesis Example 2

Synthesis of N-vinylpyrrolidone and gamma-methacryloxypropyltrimethoxysilane copolymer (copolymer B2)

50 g of N-vinylpyrrolidone, 50 g of gamma-methacryloxypropyltrimethoxysilane, 0.2 g of azobisbutyronitrile and 400 g of isopropyl alcohol were added to a reaction tank equipped with a mechanical stirrer, and the stirring speed was 400 rpm in a nitrogen atmosphere. After stirring, all the reactants were completely dissolved, and the reaction mixture was heated to 70 ° C. for 5 hours. The reaction was then cooled to terminate the reaction. The obtained reaction was reprecipitated in water to give a white solid. The obtained polymer was examined for chemical shifts to each hydrogen atom of the obtained polymer using nuclear magnetic resonance spectroscopy.

Yield: 60 g (60%)

¹ HNMR (CCl ₄ ): ?? (ppm), 1.0-1.1 (d, 3H, CH ₃ ), 2.9-3.3 (m, 2H, CH ₂ ), 3.5 (s, 3H, -OCH ₃ )

GPC (DMF): M _n = 35,000, M _w = 110,000

Looking at the nuclear magnetic resonance spectroscopy data, it can be seen that the gamma-methacryloxypropyltrimethoxysilane participated in the polymerization from the double methyl hydrogen peak between the chemical shift 1.0-1.1ppm, a broad range between 2.9-3.3ppm It can be seen from the methylene hydrogen peak of the pyrrolidone ring that N-vinylpyrrolidone participated in the polymerization. It can also be seen from the 3.5 ppm single methoxy hydrogen peak that gamma-methacryloxypropyltrimethoxysilane did not hydrolyze.

Synthesis Example 3

Synthesis of N-vinylpyrrolidone and gamma-methacryloxypropyltrimethoxysilane copolymer (copolymer B3)

30 g of N-vinylpyrrolidone, 70 g of gamma-methacryloxypropyltrimethoxysilane, 0.2 g of azobisbutyronitrile and 400 g of isopropyl alcohol were added to a reaction tank equipped with a mechanical stirrer, and the stirring speed was 400 rpm in a nitrogen atmosphere. After stirring, all the reactants were completely dissolved, and the reaction mixture was heated to 70 ° C. for 5 hours. The reaction was then cooled to terminate the reaction. The reaction product was reprecipitated in water to give a white solid. Nuclear magnetic resonance spectroscopy was used to investigate the chemical shifts for each hydrogen atom of the obtained polymer.

Yield: 61 g (61%)

¹ HNMR (CCl ₄ ): ?? (ppm), 1.0-1.1 (d, 3H, CH ₃ ), 2.9-3.3 (m, 2H, CH ₂ ), 3.5 (s, 3H, -OCH ₃ )

Looking at the nuclear magnetic resonance spectroscopy data, it can be seen that the gamma-methacryloxypropyltrimethoxysilane participated in the polymerization from the methyl hydrogen peak between the chemical shift 1.0-1.1ppm, the broad blood between 2.9-3.3ppm It can be seen from the methylene hydrogen peak of the rolidone ring that N-vinylpyrrolidone participated in the polymerization. It can also be seen from the 3.5 ppm single methoxy hydrogen peak that gamma-methacryloxypropyltrimethoxysilane did not hydrolyze.

Synthesis Example 4

Synthesis of N-vinylpyrrolidone and gamma-methacryloxypropyltriethoxysilane copolymer (copolymer B4)

50 g of N-vinylpyrrolidone, 50 g of gamma-methacryloxypropyltriethoxysilane, 0.2 g of azobisbutyronitrile and 400 g of isopropyl alcohol were added to a reaction tank equipped with a mechanical stirrer, and the stirring speed was 400 rpm in a nitrogen atmosphere. After stirring, all the reactants were completely dissolved, and the reaction mixture was heated to 70 ° C. for 5 hours. The reaction was then cooled to terminate the reaction. The reaction product was reprecipitated in water to give a white solid. Nuclear magnetic resonance spectroscopy was used to investigate the chemical shifts for each hydrogen atom of the obtained polymer.

Yield: 58 g (58%)

¹ HNMR (CCl ₄ ): ?? (ppm), 1.0-1.1 (d, 3H, CH ₃ ), 2.9-3.3 (m, 2H, CH ₂ ), 3.8 (q, 3H, -OCH _2- )

Looking at the nuclear magnetic resonance spectroscopy data, it can be seen that the gamma-methacryloxypropyltrimethoxysilane participated in the polymerization from the methyl hydrogen peak between the chemical shift 1.0-1.1ppm, the broad blood between 2.9-3.3ppm It can be seen from the methylene hydrogen peak of the rolidone ring that N-vinylpyrrolidone participated in the polymerization. It can also be seen from the 3.8 ppm ethoxy methylene hydrogen peak that gamma-methacryloxypropyltrimethoxysilane did not hydrolyze.

Synthesis Example 5 (Hydrophilic Polymer A1)

50 g of the copolymer B1 obtained in Synthesis Example 1, 5 g of pure water, and 50 g of methyl alcohol were added to a reaction tank equipped with a mechanical stirrer and a reflux condenser, mixed well, and heated with stirring at 60 ° C. for 10 hours. The reaction product was dried in vacuo to remove the solvent to give a white solid. The obtained polymer (hydrophilic polymer A1) was analyzed by nuclear magnetic resonance spectroscopy to investigate the chemical shift of each hydrogen atom.

Yield: 48 g (quantitative)

¹ HNMR (CCl ₄ ): ?? (ppm), 1.0-1.1 (d, 3H, CH ₃ ), 2.9-3.3 (m, 2H, CH ₂ )

Looking at the nuclear magnetic resonance spectroscopy data, it can be seen that the trimethoxy portion of the copolymer B1 was hydrolyzed from the disappearance of the methoxy hydrogen peak of 3.5 ppm chemical shift.

Synthesis Example 6-8

The copolymers B2-B4 obtained in Synthesis Example 2-4 were respectively hydrolyzed and purified according to the method of Synthesis Example 5 to obtain hydrophilic polymers A2-A4.

Each component and the obtained product used in Synthesis Example 1-4 and Synthesis Example 5-8 are summarized in Table 1 below.

Synthetic Example Synthesis Example 1 Synthesis Example 2 Synthesis Example 3 Synthesis Example 4 N-vinylpyrrolidone 70 50 30 50 Gamma-methacryloxypropyltrimethoxysilane 30 50 70 Gamma-methacryloxypropyltriethoxysilane 50 Product before hydrolysis Copolymer B1 Copolymer B2 Copolymer B3 Copolymer B4 Product after hydrolysis Synthesis Example 5 Synthesis Example 6 Synthesis Example 7 Synthesis Example 8 Hydrophilic Polymer A1 Hydrophilic Polymer A2 Hydrophilic Polymer A3 Hydrophilic Polymer A4

Synthesis Example 9

Hydrolysis of Gamma-Glycidoxypropyltrimethoxysilane (Hydrophilic Monomer C)

50 g of gamma-glycidoxypropyltrimethoxysilane, 5 g of pure water, and 50 g of methyl alcohol were added to a reactor equipped with a mechanical stirrer and a reflux condenser, and mixed uniformly. It was heated at 60 ° C. for 10 hours. The reaction product was dried in vacuo to remove the solvent and give a clear liquid. The chemical shift with respect to the hydrogen peak of the obtained liquid was investigated by nuclear magnetic resonance spectroscopy.

Yield: 42 g (quantitative)

¹ HNMR (CCl ₄ ): ?? (ppm), 0.4 and 1.5 (m, 4H, CH ₂ CH ₂ ), 2.4, 2.6 and 3.0 (m, t, m, 3H, CH ₂ CH-epoxy)

It can be seen that gamma-methacryloxypropyltrimethoxysilane was hydrolyzed because the hydrogen peak of a single methoxy group having a chemical shift of 3.5 ppm in the nuclear magnetic resonance spectroscopy did not appear.

Example 1-18

In order to examine the effect of the present invention using the various hydrophilic polymers A1-A4 obtained in Synthesis Example 5-8 was prepared a coating composition with the components and component ratios shown in Table 2 and Table 3. The obtained coating composition was immersed in a tissue and then thinly applied to the large glass mirror of the bathroom by a wiping method and left at room temperature for 5 minutes.

The water droplet prevention time was measured by spraying hot water at 40 ° C. onto the glass on which the coating film was formed by using a general shower connected to a hot water boiler, and measuring the time that the water film was kept clean without generating water droplets directly on the water. The anti-fog time is a measure of the time at which the steam starts to frost in 10% of the area that is not directly in contact with water. The results are shown in Tables 2 and 3 below.

Example One 2 3 4 5 6 7 8 9 `10 Hydrophilic polymer A1 One 3 3 3 5 One 2 3 A2 One A3 3 5 A4 One 5 Hydrophilic Monomer C 2 One pure 45 40 10 10 10 50 20 50 5 15 Methyl alcohol 44 87 85 47 46 90 Ethyl alcohol 57 85 75 80 Colloidal silica 0.1 0.5 1.0 0.5 1.0 0.5 0.1 0.5 0.5 1.0 Drop generation prevention time (hours) 10 10 10 12 11 10 10 10 12 10 Anti-fog time (hours) 7 7 8 15 8 14 6 7 8 9

Example 11 12 13 14 15 16 17 18 Hydrophilic polymer A1 A2 3 3 3 2 5 A3 3 5 3 2 A4 2 Hydrophilic Monomer C 2 One Polyvinylpyrrolidone 2 One Hydroxypropyl cellulose pure 20 10 10 50 10 80 7 90 Methyl alcohol 75 30 50 20 85 10 90 5 Ethyl alcohol 47 35 26 5 5 Colloidal silica 0.1 0.5 1.0 0.5 1.0 0.5 0.5 1.0 Drop generation prevention time (hours) 10 10 12 12 11 12 10 12 Anti-fog time (hours) 6 9 8 15 13 10 9 9

From the above table, Examples 1-3, 5, 7-, wherein the coating composition was prepared using one or a mixture of two or more of the hydrophilic polymers A1, A2, A3 and A4 obtained in Synthesis Example 5-8 At 10, 12-13, 16, and 18, water droplet prevention is maintained for more than 10 hours, and anti-fog time is maintained for more than 6 hours, which is very long, indicating commercial value. In addition, as can be seen from each example, it can be seen that the solvent obtained by combining pure water, methyl alcohol, ethyl alcohol, and the like is not significantly affected by the composition ratio thereof. Therefore, it is not necessary to calculate and mix their composition ratio separately for the production of these solvents.

On the other hand, when using a hydrophilic polymer and a hydrophilic monomer together it can be seen that the retention time of the water droplet generation prevention function and the anti-fog function as in Examples 4, 6, 14 and 15 is further increased. That is, when the hydrophilic polymer and the hydrophilic monomer are used at the same time, it can be seen that the effect is further enhanced. When the hydroxypropyl cellulose or polyvinylpyrrolidone, which is a kind of hydrophilic resin, is added to the composition as in Examples 11 and 17, it can be confirmed that there is no difference in effect.

Comparative Example 1-11

To prepare a coating composition with the components and component ratios as shown in Table 4 below and examined the effect thereof. A review of this was carried out in the same manner as the effect was tested in each of the above examples. That is, the water droplet prevention time was measured by spraying hot water at 40 ° C. on a glass with a coating film with a common shower connected to a hot water boiler while keeping the water film clean without generating water droplets directly on the water. The time at which the steam began to frost was measured in 10% of this non-direct area.

Comparative Example One 2 3 4 5 6 7 8 9 10 11 Hydrophilic polymer A1 2 A2 2 A3 0.5 2 A4 2 Hydrophilic Monomer C 3 2 Copolymer B1 3 2 Copolymer B4 5 Gamma-Glycidoxypropyltrimethoxysilane 3 Polyoxyethylene (20) sorbitan monostearate 2 2 2 Sodium Lauryl Sulfate 2 2 Polyvinylpyrrolidone 3 2 2 2 pure 20 20 40 5 10 50 20 50 10 10 20 Methyl alcohol 30 68 57 90 46 20 10 Ethyl alcohol 49.5 87 46 77 85 26 24 Colloidal silica 0.1 0.5 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Water droplet prevention time (minutes) 2 12 One One 0 5 One One 5 5 One Anti-fog time (minutes) 3 9 0 0 0 30 10 0 10 10 10

In Table 4, in the case of Comparative Example 1, only 0.5g of A3 is used as the hydrophilic polymer. In this case, the amount of the hydrophilic polymer added is so small that the retention time of the anti-damp function and the anti-fog function are significantly reduced. Can be. On the contrary, in the case of Comparative Example 2, 8g of A1, A2, A3 and A4 were used as the hydrophilic polymer. Rather, it may become opaque.

In Comparative Examples 9 and 10 using the hydrophilic monomer C, some water droplet generation prevention function and anti-fog function are shown, but since it is within a maximum of 1 hour, it is too short to be of no commercial value. The anti-fog function is also insufficient in Comparative Examples 3, 4 and 8 using B1 and B4 which are intermediate polymers of Synthesis Example 1 and Synthesis Example 4. Comparative Examples 6, 10, and 11 using polyoxyethylene (20) sorbitan monostearate and sodium lauryl sulfate, which are common surfactants, also have a slight anti-drop function and anti-fog, but within a maximum of 1 hour. This too is too short to be of commercial value. In the case of the comparative example 5, when gamma-glycidoxy propyltrimethoxysilane was used, it can be seen that the effect is insignificant. Comparative Examples 7-9 and 11 using polyvinylpyrrolidone, which is a kind of hydrophilic resin, also have some water droplet generation prevention function and anti-fog function, but even in these cases, the holding time is not satisfactory as a maximum of 1 hour.

It can be seen from the above-described examples and comparative examples that the coating composition of the present invention produced according to the method of the present invention shows a superior effect compared to the conventional coating composition.

In the above, the coating composition prepared according to the method of the present invention has been described as an example of application to glass in a bathroom with a lot of water. However, the water glasses, car window, lens, cover of a specific device, window glass, various films Of course, it can be applied to all products that require functions such as pollution prevention, water droplet prevention, anti-fog, etc., of course.

As described above, the coating composition prepared according to the method of the present invention has a cleaning power, and since the coating coating applied by cleaning is not easily dissolved in water, it has a function of preventing pollution for a long time, and prevents water generation and prevents antifogging. As an enemy. Therefore, if the coating composition is periodically applied to the glass surface, it is possible to prevent contamination and damage of the glass surface. It is also of high commercial value because the coating is maintained for at least 10 hours in a continuous shower. In other words, even in public baths once a day can be applied to maintain a clean mirror surface without the generation of water droplets and steaming and at the same time it is possible to continuously prevent contamination and damage of the mirror surface.

Claims (8)

A coating composition comprising a hydrophilic polymer obtained by hydrolyzing a copolymer obtained by copolymerizing a gamma-methacryloxypropyltrialkoxysilane monomer and an N-vinylpyrrolidone monomer (the alkoxy group has 1 to 2 carbon atoms). The coating composition according to claim 1, wherein the gamma-methacryloxypropyltrialkoxysilane and the N-vinylpyrrolidone are used in a weight ratio of 30:70 to 70:30. The coating composition of claim 1, wherein the coating composition consists of 1-6% by weight of the hydrophilic polymer and 90-97% by weight of water and / or an organic solvent. The coating composition of claim 3, wherein the organic solvent is methyl alcohol, ethyl alcohol or a mixture thereof. The coating composition according to claim 1, further comprising a hydrophilic monomer obtained by hydrolyzing 2 parts by weight or less of gamma-methacryloxypropyltrialkoxysilane based on 100 parts by weight of the coating composition. The coating composition of claim 1, further comprising 0.1-1.0 parts by weight of colloidal silica as an abrasive with respect to 100 parts by weight of the coating composition. Copolymerizing a gamma-methacryloxypropyltrialkoxysilane monomer and an N-vinylpyrrolidone monomer to prepare a copolymer thereof; Hydrolyzing the copolymer in water and an organic solvent; And A method for producing a coating composition comprising diluting the hydrolyzate with water and / or an organic solvent (the alkoxy group has 1 to 2 carbon atoms). 8. The method of claim 7, wherein the solvent used in the hydrolysis process is a mixture of water and methyl alcohol, and the solvent used for the dilution is at least two selected from the group consisting of water, methyl alcohol and ethyl alcohol. Manufacturing method.