KR20090110672A - Functional coating composition for preventing contamination and coating method using the same - Google Patents

Abstract

PURPOSE: A composition of a functional coating agent and a coating method using the same are provided to maintain high hydrophilic property without additional intermediate layer. CONSTITUTION: A method for coating a composition of a functional coating agent to prevent pollution comprises: a step of adding titanic compound and stabilizing agent to alcohol to prepare titanic compound-dispersed sol(S110); a step of adding silicide and then stabilizing the agent to prepare silicic compound binder(S120); a step of adding surfactant and hydrophilic agent to alcohol or ultra pure water(S130); a step of mixing titanic compound sol, silicic compound binder, and supplemental additive in the weight ratio of 1:2-5:0.5-3(S140); and a step of heating at 100-150°C(S150).

Description

Functional coating composition for preventing contamination and coating method using the same}

The present invention relates to a functional coating composition exhibiting super hydrophilicity and a coating method using the same, and more particularly, to a functional coating composition and a coating using the same, which exhibit a pollution prevention function by highly hydrophilizing surfaces such as mirrors, lenses, glass, ceramics, and the like. It is about a method.

In the case of materials such as windshield, rearview mirror, helmet protection glass, etc., which have been used in the past, when water droplets are attached to the surface due to rainfall, heavy rain, or other causes, the surface becomes cloudy and loses visibility. there was.

In addition, materials such as lenses of glasses, windows of buildings, covers of various instrument panels, mirrors of bathrooms and washrooms, medical mirrors, endoscope lenses, etc., cause moisture or frost to form on the surface due to temperature and humidity changes indoors and outdoors. As a result of the problem, it is difficult to secure the field of vision, causing inconvenience and causing various accidents.

In addition, in the field of construction and paints, the surface of the building exterior material or paint is contaminated by various suspended substances in the air, such contamination may include combustion products such as carbon black or inorganic materials such as clay particles. It is caused by flying in the air and attached to the roof, exterior walls, windows, etc. of the building.The pollutants are mixed with rainwater during the rain and flow down the exterior walls of the building, but are not completely removed. The traces of the remaining was also a problem that takes a separate cleaning cost to remove these traces.

In order to solve the above problems, a method of making a surface of a conventional material hydrophilic has been proposed. In Japanese Patent Laid-Open No. 3-129375, a method of coating a polymer polymer layer on a mirror surface, irradiating ultraviolet rays thereto, and then treating with an aqueous alkali solution to generate an acid group makes the surface of the polymer layer hydrophilic and prevents blurring of the mirror. Is disclosed.

However, such a prior art has a problem in that the manufacturing process is complicated, and once the contaminants are attached to the surface, they are not removed by themselves, so that the surface is contaminated and hydrophilicity disappears over time.

On the other hand, in order to prevent contamination of building exteriors, a method of coating a water-repellent paint such as polytetrafluoroethylene (PTFE), which does not adhere to water, has been proposed, in contrast to the above patent. Because it contains a lot of this technique did not get a good effect.

Also, in Japan, a technique for painting exterior walls of buildings with paints containing hydrophilic polymers has been proposed. The hydrophilic polymer can achieve a pollution prevention effect to a certain extent at a wet angle of 30 to 40 degrees, but the hydrophilic property of the inorganic dust represented by clay minerals and the contact angle between dust and water is 20 to 50 degrees. Because of their affinity for polymers and their ability to adhere to their surfaces, membranes of such polymers have the disadvantage that they cannot sufficiently prevent contamination of inorganic dust and dirt.

In addition, recently, as a method of improving the problems of the hydrophilic polymer coating, a photocatalytic material represented by titanium oxide is coated on the surface of the material and irradiated with ultraviolet rays, thereby forming a high hydrophilicity on the surface by photoexcitation. It is proposed how to.

The hydrophilicity obtained by using a photocatalytic material is reported to have a very good hydrophilic effect with a contact angle of 3 degrees or less.However, unlike a hydrophilic polymer membrane, light must be light to obtain hydrophilicity with a photocatalytic material. Therefore, in order to apply in real life, there is a problem that hydrophilicity is not maintained when the light source is temporarily blocked, such as evening, night, or shade.

The present invention has been made to solve the above problems, it can provide a complex functional coating composition having a high hydrophilic property to prevent contamination of the interior and exterior materials, using the functional coating composition on the surface of the interior and exterior without a separate intermediate layer It is an object to provide a coating method for forming a coating film having a high hydrophilicity.

Functional coating composition of the present invention for achieving the above object, a titanium compound dispersion sol containing an alcohol, a titanium compound, and a stabilizer; Silicon compound binders containing alcohols, silicon compounds, and stabilizers; And adjuvants containing a solvent of any one of alcohol or ultrapure water, a surfactant, and a hydrophilizing agent.

Herein, the titanium compound dispersion sol contains 1 to 15 parts by weight of titanium compound and 0.1 to 5 parts by weight of stabilizer, and the silicon compound binder is 5 to 20 parts by weight of alcohol based on 100 parts by weight of alcohol. It is preferable to contain a weight part and 0.1-3 weight part of stabilizers, and the said auxiliary agent contains 2-5 weight part of surfactants, and 5-10 weight part of hydrophilizing agents with respect to 100 weight part of solvents of either alcohol or ultrapure water. .

In addition, the titanium compound dispersion sol, the silicon compound binder and the auxiliary agent are preferably mixed in a weight ratio of 1: 2-5: 0.5-3.

In addition, the alcohol is preferably any one selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol.

In addition, the titanium compound is titanium (IV) isopropoxide, titanium (IV) butoxide, titanium (IV) ethoxide, titanium (IV) methoxide, titanium (IV) stearate and mixtures thereof It is preferably any one selected from the group consisting of.

In addition, the silicon compound is tetraethyl-orthosilicate (TEOS), tetramethyl-orthosilicate (TMOS), methyl trimethoxysilane (MTMS) and a mixture thereof It is preferably one selected.

In addition, the stabilizer is preferably any one inorganic acid selected from the group consisting of nitric acid, hydrochloric acid and mixtures thereof.

In addition, the coating method using the functional coating composition of the present invention comprises the steps of preparing a titanium compound dispersion sol by adding a titanium compound, a stabilizer to the alcohol and hydrolysis reaction; Preparing a silicon compound binder by adding a silicon compound and a stabilizer to the alcohol and performing a hydrolysis reaction; Preparing an adjuvant by adding a surfactant and a hydrophilizing agent to a solvent of either alcohol or ultrapure water and subjecting it to a hydrolysis reaction; Preparing a coating sol by mixing the titanium compound dispersion sol, the silicon compound binder, and the auxiliary agent in a weight ratio of 1: 2 to 5: 0.5 to 3; And heat-treating at 100 to 150 ° C. after coating using the coating sol.

Functional coating composition and coating method using the same of the present invention as described above,

First, the coating on the surface of the interior and exterior materials has the advantage that it shows a remarkably excellent superhydrophilic effect compared to the conventional coating agent.

Second, there is an advantage that it is possible to provide a coating method that can maintain the superhydrophilicity even in a low light source without coating a functional coating composition according to the present invention to form a separate intermediate layer.

Third, a coating composition exhibiting not only excellent contact angles directly related to hydrophilicity but also strong hardness in accelerated weather resistance and high photodegradation rate can be obtained.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical idea of the present invention, various equivalents that may be substituted for them at the time of the present application It should be understood that there may be water and variations.

Hereinafter, with reference to Figure 1 to explain a coating method using a functional coating composition according to an embodiment of the present invention. 1 is a block flow diagram showing a coating method using a functional coating composition according to an embodiment of the present invention.

Referring to Figure 1, the coating method using a functional coating composition according to an embodiment of the present invention is a) titanium compound dispersion sol preparation step (S110), b) silicate compound binder preparation step (S120), c) auxiliary agent preparation Step S130, d) coating sol preparation step (S140) and e) coating and heat treatment step (S150).

First, a titanium compound and a stabilizer are added to an alcohol and hydrolyzed to prepare a titanium compound dispersion sol (S110).

It is preferable that the said titanium compound dispersion | dissolution sol contains 1-15 weight part of titanium compounds and 0.1-5 weight part of stabilizers with respect to 100 weight part of alcohols.

The titanium compound may be an alkoxide such as titanium tetraethoxide, titanium tetramethoxide, titanium tetraisopropoxide, titanium tetrabutoxide, and the like. And water-soluble inorganic compounds such as titanium acetate, titanium chloride (TiCl ₄ ), titanium sulfate, and titanium sulfate, or titanium hydroxide.

However, in the case of the water-soluble inorganic compound, a high temperature of 600 ° C. or higher is required during the heat treatment, so that an alkoxide is preferably used as the titanium compound, more preferably titanium (IV) isopropoxide. , Any one selected from the group consisting of titanium (IV) butoxide, titanium (IV) ethoxide, titanium (IV) methoxide, titanium (IV) styrate and mixtures thereof.

In addition, the alcohol is preferably a lower alcohol of C1 ~ C4 as any one selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol.

In addition, the stabilizer is preferably any one inorganic acid selected from the group consisting of nitric acid, hydrochloric acid, and mixtures thereof.

The addition amount of the stabilizer may vary depending on the molecular weight, but if it is contained less than 0.1 parts by weight of alcohol, there is a problem that the size of the particles is large because the stabilizing action is not sufficient, if the cost exceeds 5 parts by weight In addition to the disadvantages, the pH of the titanium compound dispersing sol is changed to a strong acid, there is a disadvantage that the dispersibility is deteriorated, there is a high possibility of precipitation.

Further, the stabilizer is more preferably contained in 1 to 3 parts by weight with respect to 100 parts by weight of alcohol.

In addition, a silicon compound and a stabilizer are added to the alcohol and hydrolyzed to prepare a silicon compound binder (S120).

It is preferable that the said silicon compound binder contains 5-20 weight part of silicon compounds, and 0.1-3 weight part of stabilizers with respect to 100 weight part of alcohols.

The silicon compound is preferably any one selected from the group consisting of tetraethylorthosilicate (TEOS), tetramethylorthosilicate (TMOS), methyltrimethoxysilane (MTMS), and mixtures thereof.

In addition, it is more preferable to add any one of the organosilicon oxides selected from water glass or colloidal silica to the silicon compound. When the organosilicon oxide is further added, the adhesiveness to the panel is further improved.

In addition, a surfactant and a hydrophilizing agent are added to the solvent of any one of alcohol or ultrapure water and hydrolyzed to prepare an auxiliary agent (S130). It is preferable that the said adjuvant contains 2-5 weight part of surfactants, and 5-10 weight part of hydrophilizing agents with respect to 100 weight part of solvents of either alcohol or ultrapure water.

When the surfactant is contained in an amount of more than 5 parts by weight based on 100 parts by weight of the solvent of any one of alcohol or ultrapure water, foaming may occur after synthesis, and a problem may occur in workability. If it contains more than 10 parts by weight based on 100 parts by weight of any one solvent, there is a problem that the photocatalytic activity effect is also reduced because the absolute amount of titanium dioxide is reduced.

The order of preparing the titanium compound dispersion sol, the silicon compound binder and the auxiliary agent may be any time sequence, and the titanium compound dispersion sol and the silicon compound binder may be prepared according to the object of the present invention. And adjuvants may be prepared simultaneously or in altered order.

The hydrophilic agent is preferably a silicon compound, such as silicon, including silicon atoms substituted with organic groups, and more preferably, the organic group may be any one selected from n-propyl group or phenyl group.

Use of such a hydrophilizing agent can speed up the rate at which the organic group bonded to the silicon atom is substituted with a hydroxyl group by photoexcitation.

As described above, when the titanium compound dispersion sol, the silicon compound binder, and the auxiliary agent are prepared, the titanium compound dispersion sol, the silicon compound binder, and the auxiliary agent are mixed in a weight ratio of 1: 2 to 5: 0.5 to 3 to obtain a sol state. As a functional coating composition, a coating sol is prepared (S140).

Here, in the coating sol, when the silicon compound binder is less than 2 parts by weight with respect to 1 part by weight of the titanium compound dispersion sol, the adhesive strength after coating is rapidly weakened, so that it does not exhibit long-term antifouling effect and sufficient hydrophilicity. If the silicon compound binder is contained in an amount of more than 5 parts by weight with respect to 1 part by weight of the titanium compound dispersion sol, peeling of a part of the panel may occur after coating, and the viscosity may increase, resulting in poor workability. There is a problem.

In addition, when the content of the adjuvant is less than 0.5 parts by weight based on 1 part by weight of the titanium compound dispersion sol, there is a problem in that the initial wetting is not good. When the content exceeds 3 parts by weight, the surface becomes white after coating and heat treatment. This can happen.

When the coating sol mixed with the above mixing ratio is prepared, the coating sol may be coated on the surface of the interior and exterior materials using the coating sol, and heat-treated at 100 to 150 ° C. to prepare a superhydrophilic coating film. There is (S150).

In this case, when the heat treatment temperature is out of 100 to 150 ° C., surface strength may be reduced or damage may occur to the base material itself. In other words, when the heat treatment temperature is less than 100 ° C., the strength of the surface may drop or peeling may appear on the surface. And, if it exceeds 150 ℃ there is a problem that the coated base material itself is damaged.

Hereinafter, the production process of the functional coating composition according to the present invention will be described through Example 1 below.

Example  1: Preparation of Functional Coating Composition

1) Preparation of Titanium Compound Dispersion Sol

After adding 5 g of 67% nitric acid (HNO ₃ ) and 500 g of titanium (IV) isopropoxide (TTIP) to 5 kg of 95% ethanol, the rotation speed of the stirrer was fixed at 1000 rpm, and the mixture was heated to 80 ° C. for 30 minutes. The hydrolytic synthesis was carried out by decomposition and hydrolysis at 90 ° C. for 12 hours, and then cooled to room temperature and discharged through an outlet to prepare a transparent titanium compound dispersion sol.

2) Preparation of Silicon Compound Binder

200 g of tetramethylorthosilicate (TMOS) and 2 g of 67% nitric acid (HNO ₃ ) were added to 1 kg of 95% ethanol, and the mixture was stirred at 50 ° C for 1 hour, followed by 50 g of 2-butoxyethanol. The silicon compound binder was prepared by stirring for 2 hours.

3) Preparation of Hydrophilization Aids

50 g of S-4360 (Parkizing), a hydrophilizing agent, was added to 1 kg of ultrapure water, and stirred at an elevated temperature of 70 ° C. for 1 hour. Then, 50 g of Triton X-100 (Duksan Chem.), A nonionic surfactant, was added thereto for 3 hours. Was stirred to prepare an adjuvant with hydrophilicity.

4) Preparation of Functional Coating Composition

100 g of the titanium compound-dispersed sol prepared as described above, 300 g of the silicon compound binder, and 200 g of the hydrophilization aid were mixed and stirred to prepare a sol-type functional coating composition.

Hereinafter, the contact angle, accelerated weather resistance and photodegradation rate of the functional coating composition of the present invention prepared according to Example 1 will be described with reference to Experimental Examples 1 to 3.

Experimental Example  One : Contact angle  exam

The functional coating composition prepared according to Example 1 was spray-coated on an aluminum panel, glass, and polycarbonate panel with a coating automatic coating device (Unity Co., Ltd., Patent No. 10-0689794). The contact angle of the coated aluminum panel, glass, and polycarbonate panel was measured by a contact angle meter (Germany, DSA-100), and the results are shown in Table 1, FIGS. 2A to 2C.

Figure 2a is a photograph showing the contact angle before and after the coating of the aluminum panel, Figure 2b is a photograph showing the contact angle before and after the coating of the glass, Figure 2c is a photograph showing the contact angle before and after the coating of the polycarbonate panel.

Before coating After coating Aluminum (Al) Composite Panel 92.8 8.8 Glass 90.3 5.6 Polycarbonate panels 93.6 11.5

As can be seen in Table 1, the contact angle of the panel coated with the functional coating composition according to the present invention showed a very good hydrophilicity before the coating.

That is, referring to Figures 2a to 2c, (a) contact angle before the coating of the aluminum composite panel, respectively, was 92.8 degrees, while (b) contact angle after coating the functional coating composition according to the present invention appeared 8.8 degrees, glass In the panel, the contact angle before coating (a) was 29.8 degrees, while the contact angle after coating the functional coating composition according to the present invention (b) was 5.6 degrees. In the polycarbonate panel, the contact angle before coating (a) was 93.6 degrees. The contact angle after coating the functional coating composition according to the invention (b) was 11.5 degrees.

Accordingly, in the case of the panel coated with the functional coating composition according to the present invention, it was confirmed that the contact angle is significantly lowered to show excellent hydrophilicity.

Experimental Example 2 accelerated weathering test

The functional coating composition prepared according to Example 1 was spray-coated on an aluminum panel, glass, and polycarbonate panel with a coating automatic coating device (Unity Co., Ltd., Patent No. 10-0689794). Accelerated weathering test was conducted to check the durability of the coated substrate surface. Accelerated weathering was measured with a QUV weathering meter (QUV-SE), and the results are shown in Table 2 below.

Before coating After coating Aluminum (Al) Composite Panel 650 hr 800 hr Glass 900 hr 1000hr Polycarbonate panels 500hr 600hr

As can be seen in Table 2, when the functional coating composition according to the present invention is coated, excellent accelerated weather resistance appeared compared to before coating.

Experimental Example  3: Measurement of photodegradation rate by liquid film adhesion

The functional coating composition prepared according to Example 1 was spray-coated on an aluminum panel, glass, and polycarbonate panel with a coating automatic coating device (Unity Co., Ltd., Patent No. 10-0689794). In order to determine the photodegradation rate on the surface of the coated substrate, a liquid film adhesion method, which is a test method of the Photocatalyst Association, was performed, and the results are shown in Table 3 below.

Liquid film adhesion method is a method of measuring the self-cleaning (Self cleaning) performance by injecting methylene blue solution to the specimen and observing the presence of decolorization.

Before coating 30 minutes after coating 1 hour after coating Aluminum (Al) Composite Panel No discoloration Partial discoloration decolorization Glass No discoloration Discoloration decolorization Polycarbonate panels No discoloration Partial discoloration decolorization

As can be seen in Table 3, the results of the photodegradation test of the panel coated with the functional coating composition according to the present invention showed that the accelerated weather resistance of the methylene blue solution after one hour compared to before coating.

As mentioned above, although this invention was demonstrated by the limited embodiment and drawing, this invention is not limited by this, The person of ordinary skill in the art to which this invention belongs, Of course, various modifications and variations are possible within the scope of equivalent claims.

1 is a block flow diagram showing a coating method using a functional coating composition according to an embodiment of the present invention,

2A and 2B are photographs comparing the contact angles of a panel coated with a panel before coating by a coating method using the functional coating composition shown in FIG. 1.

Claims (8)

Titanium compound dispersion sols containing alcohol, a titanium compound, and a stabilizer; Silicon compound binders containing alcohols, silicon compounds, and stabilizers; And A functional coating composition comprising an auxiliary agent containing a solvent of either alcohol or ultrapure water, a surfactant, and a hydrophilizing agent. The method of claim 1, The titanium compound dispersion sol contains 1 to 15 parts by weight of a titanium compound and 0.1 to 5 parts by weight of a stabilizer based on 100 parts by weight of alcohol, The silicon compound binder contains 5 to 20 parts by weight of silicon compound and 0.1 to 3 parts by weight of stabilizer based on 100 parts by weight of alcohol, The auxiliary agent contains 2 to 5 parts by weight of the surfactant and 5 to 10 parts by weight of the hydrophilizing agent based on 100 parts by weight of the solvent of any one of alcohol or ultrapure water. The method of claim 1, The titanium compound dispersion sol, the silicon compound binder and the auxiliary agent is a functional coating composition, characterized in that mixed in a weight ratio of 1: 2-5: 0.5-3. The method according to claim 1 or 2, The alcohol is a functional coating composition, characterized in that any one selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol. The method according to claim 1 or 2, The titanium compound is any one selected from the group consisting of titanium (IV) isopropoxide, titanium (IV) butoxide, titanium (IV) ethoxide, titanium (IV) methoxide, titanium (IV) styrate and mixtures thereof. Functional coating composition, characterized in that one. The method according to claim 1 or 2, The silicon compound is one selected from the group consisting of tetraethylorthosilicate (TEOS), tetramethylorthosilicate (TMOS), methyltrimethoxysilane (MTMS), and mixtures thereof. Functional Coating Composition. The method according to claim 1 or 2, The stabilizer is a functional coating composition, characterized in that any one inorganic acid selected from the group consisting of nitric acid, hydrochloric acid and mixtures thereof. Preparing a titanium compound dissolving sol by adding a titanium compound and a stabilizer to the alcohol and performing a hydrolysis reaction; Preparing a silicon compound binder by adding a silicon compound and a stabilizer to the alcohol and performing a hydrolysis reaction; Preparing an adjuvant by adding a surfactant and a hydrophilizing agent to a solvent of either alcohol or ultrapure water and subjecting it to a hydrolysis reaction; Preparing a coating sol by mixing the titanium compound dispersion sol, the silicon compound binder, and the auxiliary agent in a weight ratio of 1: 2 to 5: 0.5 to 3; And Coating method using a functional coating composition comprising the step of heat treatment at 100 ~ 150 ℃ after coating using the coating sol.

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