KR20150114811A - A paint composition containing multiple aerogel and its menufacturing method - Google Patents

Abstract

The present invention relates to a paint composition and a preparation method thereof, wherein an aerogel composite is included in a paint composition. According to the present invention, a UV blocking material including carbons is integrally bonded in a uniform way to a base material which can be formed with aerogel, thereby allowing the aerogel base material and the UV blocking material to interact and provide a synergistic effect while integrally bonded to each other to provide more improved thermal insulation performance, compared to a conventional paint. In addition, the base material and the UV blocking material are integrally formed through a sol-gel process, thereby making additional bonding of a functional material easy and firm and readily providing various functions as well as excellent thermal insulation performance.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a paint composition containing a composite airgel,

The present invention relates to an adiabatic paint and a method for producing the same, and more particularly, to a paint composition containing a composite airgel and a method for producing the same.

Conventional insulating paints have been used in the form of blending a hollow ceramic powder mainly composed of SiO ₂ (silica) and Al ₂ O ₃ (alumina) in paints (Korean Patent Publication No. 2004-22985 and Korean Patent Laid- 2001-372).

Such conventional heat insulating paint has a problem that it is difficult to evenly disperse the hollow ceramic powder into the paint, and when the paint containing the ceramic powder is left for a long time, the hollow ceramic powder and other fillers due to the weight difference are separated into upper and lower layers . Further, when it is applied in the form of a paint, there arises a problem that sufficient drying occurs. As a result, the adiabatic properties are deteriorated.

In addition, since the hollow ceramic material in such a shape does not provide a sufficient heat insulating effect, the heat insulation characteristic of the paint is insufficient.

Korean Patent Publication No. 2007-117413 discloses a method of producing an inorganic binder and adding a solid component (vermiculite powder), a secondary solid component (titanium oxide), a dispersing agent, a flow control agent, etc. to an inorganic binder to impart heat insulation to the paint have.

However, this method has a problem in that it is difficult to manufacture, requires a lot of time and cost, and has insufficient heat insulation, which is ineffective.

In order to further improve the heat insulating property of the coating material, a technique has been disclosed in which an airgel excellent in heat insulation property is contained in the coating material. In more detail, a silica airgel or a titanium dioxide airgel is separately contained in a coating material Or the silica airgel and the titanium dioxide airgel are mixed with each other to improve the heat insulating property of the coating material.

However, in the conventional art in which an airgel is incorporated into the paint as described above, the silica airgel has a relatively low density and the titanium dioxide airgel has a relatively large density, which is poured on the upper or lower side of the paint, , Even when the above two materials are mixed and contained in the coating material, they are separated from each other during the drying process of the coating due to the difference in density, so that it is difficult to provide an effective heat insulation performance.

Korean Patent Laid-Open No. 10-2010-0085472 (published on July 29, 2010) 'Super-heat-insulating airgel-containing paint containing aerogels'

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a coating composition comprising a composite airgel, The present invention is directed to providing a coating composition containing a composite airgel and a method of manufacturing the composite composition, wherein the coating composition is formed as a single-bonded structure, .

Hereinafter, the present invention will be described in order to achieve the above-mentioned object.

The coating composition containing the composite airgel according to the present invention comprises: a resin liquid for coating formed of a liquid resin; A composite airgel which is formed in an integral bonding structure in which an infrared ray blocking material is embedded in a three-dimensional net structure forming a base material and is added in powder form to the resin solution for painting; Wherein the infrared blocking material is carbon, or carbon and titanium dioxide are complex-formed at a predetermined weight ratio.

In addition, a method for producing a coating composition containing a composite airgel according to the present invention is characterized in that a powdery infrared blocking material is added to a mixture of water and water, and carbon is added as the infrared blocking material Adding carbon and titanium dioxide in a predetermined weight ratio and stirring, and then adding a catalyst to gel to form a composite airgel; And adding the composite airgel to the resin solution for coating.

The present invention having the above-described structure can provide the following technical and economic effects.

First, in forming the aerogel included in the coating composition according to the present invention, the base material and the infrared ray blocking material blocking infrared rays are formed as a composite structure by integrally bonding the base material and the infrared ray blocking material on the basis of the airgel base material that provides basic insulation performance , And carbon or carbon and titanium dioxide are mixed and used as the infrared ray blocking material at a constant weight ratio. By using the infrared ray blocking material, a synergistic effect due to the interaction between the integrally bonded aerogel base material and the infrared ray blocking material improves the heat insulation performance There is a technical effect that can be provided.

Secondly, in uniformly bonding the aerogel base material and the infrared ray blocking material uniformly, the infrared ray blocking material is stirred in a powder state to a mixture solution (sol) in which the base material and water are mixed so that the infrared ray blocking material is integrally formed in the process of gelation Thus, there is a technical effect that the additional bonding of the functional material is simple, the bonding is uniform and rigid, the excellent heat insulating performance and various functionalities can be easily provided.

Hereinafter, the present invention will be described in more detail.

First, the coating composition according to the present invention comprises: a resinous liquid for coating formed of a liquid resin capable of developing a certain color; A composite airgel added to the resin liquid for coating the liquid in the form of a powder having a structure in which a base material and an infrared blocking material are uniformly formed integrally; .

The resin liquid for coatings is a base material of the composition for paints according to the present invention. More specifically, the resin liquid for paints includes liquid acrylic resin, silane resin, siloxane resin, phthalic acid resin, vinyl chloride resin, epoxy resin, Urethane resin, and aminoalkyd resin.

The composite airgel may be put in a powder form and stirred. In the composite airgel, the composite airgel may be formed in a form of an airgel, Is formed integrally with the infrared ray blocking material. It is preferable that the resin liquid for coating and the composite airgel are mixed at a ratio of 40 to 95% by weight of the resin solution for paint to 5 to 60% by weight of composite airgel.

More specifically, the base material is formed in a three-dimensional network structure, and the infrared blocking material has a size of nanometers to several tens of micrometers smaller than that of the base material And is inherently embedded in a three-dimensional network forming a base material.

The base material is preferably formed using any one of silica, alumina, polyimide, silica-titania, silica-carbon, vanadia, zirconia, and acetate cellulose which can be formed into an aerogel shape.

(Sol) in which water is mixed with the base material, preferably 10 to 50% by weight of the base material and 50 to 90% by weight of water.

The infrared ray blocking material may be carbon alone or may be mixed with carbon at a certain ratio of infrared ray blocking material. Carbon absorbs and scatters infrared rays to block heat by radiant heat, thereby improving the thermal insulation performance of the composite airgel. As the carbon, graphite, carbon black, activated carbon, etc. may be used. The infrared blocking material may be formed to have a size of nano to several tens of micrometers. The length of the carbon used as the infrared ray blocking material is preferably about 0.1 to 50 mu m.

Preferably, titanium dioxide can be used as another infrared blocking material. Titanium dioxide, like carbon, has an effect of blocking infrared rays, and by forming two or more infrared ray blocking materials uniformly and integrally bonded to the base material, the composite airgel can exhibit better heat insulating performance by imparting compactness . Titanium dioxide is preferably used in powder form having a diameter of 300 to 500 nm. The mixing ratio of titanium dioxide to 1 part by weight of carbon is preferably about 0.1 to 2 parts by weight, particularly preferably about 0.5 to 1 part by weight.

As described above, the base material and the infrared ray blocking material, which are bonded at a fine particle size of nano to several tens of microns, are not broken and maintained even if they are pulverized into a powder form. Even if they are contained in a resin liquid for a paint, It will be done.

In addition, any functional material other than the infrared ray blocking material may be additionally formed in the size of nano to several tens of micrometers and can be combined with the base material in the same manner.

The total amount of the infrared shielding material including the other heat insulating material is preferably about 0.5 to 10% by weight based on the total weight of the composite airgel to be finally formed.

Most of the base materials have a density of 0.09 to 0.025 g / cm 3 (based on silica) when formed of aerogels, and most infrared ray blocking materials have a density of 4.1 g / cm 3 (based on titanium dioxide) There is a problem that the base material sinks to the upper part of the resin liquid for paint and the infrared ray blocking material sinks to the lower part of the resin liquid for paint. However, due to the bonding structure according to the present invention, the composite airgel is formed with the average density of both materials do.

As described above, due to the averaging of the bonding structure and the density of the two materials at the dimension of nano to several tens of micrometers, both materials are not separated from each other in the drying process of the coating material, It is possible to effectively distribute the external heat energy and the infrared wavelength.

In addition, it is also possible to control the viscosity of the resin liquid for paint containing the composite airgel as described above such that the composite airgel formed at the average density is more uniformly distributed. In order to control the viscosity, it is preferable to use fumed silica. At this time, it is preferable that the dry silica is also formed into a nano-sized powder form and stirred in a resin solution for a paint. The amount of the dry silica is preferably set to a minimum amount that can be maintained in a state in which the composite airgel is uniformly distributed . Particularly preferably, the dry silica is contained in an amount of 0.01 to 3% by weight based on the total weight of the resin liquid for paint containing the composite airgel.

Further, the coating composition of the present invention may preferably further comprise a binder. The binder may be an organic binder, an inorganic binder, or a combination of both. Since the composite airgel has a low density and is hydrophobic, it is preferable to add the organic binder and / or the inorganic binder to the resin liquid for coating and the composite airgel to form the coating composition.

Particularly preferably, the organic binder and the inorganic binder may be mixed at a certain ratio. This is because it is difficult to increase the content of the airgel in the composition by itself, and it is not preferable that the inorganic binder alone is difficult to paint and the inorganic binder itself has a high heat conductivity, which is not preferable when the amount thereof is increased. The most preferable range is 30 to 90% by weight of the organic binder and 10 to 70% by weight of the inorganic binder, and the coating can be applied in this range, and the heat insulating property and the flame retardancy are good.

It is preferable that the organic binder and the inorganic binder are added in such a ratio as to minimize the coating composition of the coating composition since the thermal conductivity increases remarkably as the content of the coating composition becomes higher as the content of the coating composition becomes higher. It is preferably added in a proportion of 5 to 50% by weight relative to the weight.

The organic binder is preferably used as a binder such as polyurethane or acrylate copolymer to increase paint adhesion and fluidity. The inorganic binder is used to increase the adhesive strength of the paint and to impart flame retardancy. Examples of the binder include potassium silicate, zinc phosphate , Talc, magnesium oxide and the like are preferably used.

In addition, it is preferable to use polyacrylamide or polynaphthalene sulfonate as the crosslinking binder among the organic binders. When the crosslinking binder is dispersed in water, the viscosity is increased to increase the mixing and bonding of the organic binder and the inorganic binder, So that the airgel is easily dispersed inside.

Among the inorganic binders, it is preferable to use a binder such as micro cement, hemihydrate gypsum, silica fume, fumed silica, lime, calcium sulfoaluminate, and the like, and the hydratable inorganic binder has a hydration function with silica The pozzolanic reaction promotes the long-term strength of the paint, improves the watertightness and durability, and densely fixes the low-density aerogels.

The coating composition of the present invention may further comprise a silicone antifoaming agent.

Further, the coating composition of the present invention may further include fibers such that the strength of the coating composition is higher than a certain level when dried. The fibers preferably have a length of 0.1 to 4 mm. As the fiber, at least one selected from polypropylene fiber, polyethylene fiber, silica fiber, alumina fiber, carbon fiber and glass fiber is preferably used.

Next, a method for producing a coating composition having the above structure will be described in detail.

First, the method of manufacturing the coating composition is a method of forming a composite airgel by adding a powdery infrared blocking material to a mixture solution (sol) in which water is mixed with a base material, stirring the mixture, and then adding a catalyst to gel ; And adding the composite airgel to the resin solution for coating.

The mixed liquid is formed by mixing a base material and water as described above. It is preferable that the base material is blended in a proportion of 10 to 50% by weight and 50 to 90% by weight of water.

After forming the mixed liquid as described above, the infrared ray blocking material is added and stirred. It is preferable that the infrared ray blocking material is formed in powder form having a size of nano to several tens of micrometers, and the mixture is added to the mixed liquid and stirred. The amount of the infrared blocking material to the mixed liquid is preferably 0.0 to 2 parts by weight, more preferably 0.1 to 1 part by weight, particularly preferably 0.2 to 0.6 part by weight based on 100 parts by weight of the mixed liquid, .

In addition, it is preferable to use carbon as the infrared blocking material or to use carbon and titanium dioxide in a certain ratio. Here, it is preferable that the titanium dioxide is formed to have a size of 300 to 500 nm and carbon is formed to have a size of 0.1 to 50 탆 Do.

As described above, when a catalyst is added to a mixed solution in which powder of infrared blocking material having a size of nano to several tens of micrometers is stirred, a complex airgel is formed. The composite airgel is formed into a structure 3 Dimensional network with infrared shielding materials having a size of nano to several tens of micrometers.

Accordingly, the base material and the infrared ray blocking material constituting the composite airgel are not separated from each other even if they are formed into powder, and they are not separated even if they are included in the resin solution for painting, and can maintain the bonded state.

Further, the process of forming a composite airgel by adding a catalyst to a mixed solution in which the infrared blocking material is stirred to form a gelled mixture is described in Korean Patent Application No. 10-2014-0008687 filed by the applicant of the present invention, A detailed description of the process will be omitted.

Hereinafter, embodiments of the present invention will be described.

≪ Example 1-1 >

complex Aerogels  Produce

Silica was used as the base material for forming the airgel, and carbon black was used as the infrared ray blocking material.

More specifically, 39% by weight of silica (= water glass) and 61% by weight of water are mixed to form a mixed solution.

2.5 grams of powdery carbon black was added to 450 grams of the above mixed liquid and stirred. At this time, the carbon black used was in powder form and had an average length of about 10 mu m.

35 g of a sulfuric acid solution diluted to a concentration of 28% by volume was added as a catalyst for gelation to the mixed solution to which the carbon black was added as described above, and the mixture was allowed to gel over a certain period of time. At this time, the silica, water, carbon black, and sulfuric acid solution are stirred in a line-mixer. In this embodiment, the silica, water, carbon black and sulfuric acid solution were formed in a hydro-gel state after 30 seconds. The hydro-gel was aged by immersing the hydro-gel in a sulfuric acid solution diluted to a concentration of 2 vol% for 5 hours through the aging process.

The hydrogel, which has undergone the aging process as described above, is subjected to an impurity cleaning process for removing impurities such as sodium ions by using water. At this time, 10 liters of the water is prepared, and the hydrogel is immersed in the hydrogel for 10 hours, And the 10 liters of water are replaced every 2 hours.

The hydrogel in which the impurities are removed through the impurity washing process is subjected to a surface modification and a solvent substitution process as described above. In this embodiment, hexamethyldisilazane (HMDS) is used as the organosilane compound in relation to the surface modification, And n-hexane as a non-polar organic solvent was used in connection with the solvent substitution.

More specifically, 1 liter of the hexane methyldisilazane and 10 liters of n-hexane were prepared, and the impurities were washed in a container holding the two solutions (HMDS, n-hexane) at 65 degrees Celsius The hydro-gel is soaked for 8 hours so that the surface modification and solvent replacement take place together.

When the surface modification and the solvent substitution are performed as described above, the hydro-gel is aerogelized and dried in a drier at 100 ° C. for 5 hours, so that a composite airgel can be formed.

≪ Example 1-2 >

complex Aerogels  Produce

Silica was used as the base material to form the aerogels, and carbon black and titanium dioxide were used as infrared blocking materials.

Carbon black and titanium dioxide were added to 450 g of the same mixture liquid (39% by weight of silica + 61% by weight of water) as in Example 1-1 in an amount of 1.25 g each as an infrared ray blocking material and stirred. 2.5 g of carbon black in the form of powder was added thereto and stirred.

At this time, the titanium dioxide used was in the form of spherical powder having an average diameter of about 405 nm, and the carbon black was in powder form and had an average length of about 10 탆.

The remainder was carried out in the same manner as in Example 1-1 to obtain a composite airgel.

≪ Example 2-1 >

Preparation of coating composition

Using the composite airgel prepared in Example 1-1, a coating composition was prepared in the composition shown in Table 1 below.

number designation Composition ratio (weight ratio) One Silica-carbon airgel 13.53 2 Micro cement 3.60 3 Half plaster 1.80 4 Silica fume 0.54 5 Fumed silica 0.13 6 lime 0.94 7 Calcium sulfoaluminate 0.31 8 Polyacrylic acid ester 4.58 9 Zinc phosphate 0.23 10 Talc 1.08 11 Potassium silicate 0.01 12 Magnesium oxide 0.06 13 Boric acid 0.23 14 Titanium dioxide 0.23 15 Silicone defoamer 0.09 16 Fiber (glass fiber, 2 mm) 0.01 17 Polyacrylamide 0.27 18 Polynaphthalene sulfonate 0.33 19 water 69.33 20 Polyurethane 2.70 100

The obtained coating composition of the present invention was produced in the form of a flat plate having a size of 25 cm in length, 25 cm in length, and 5 mm in thickness, and then dried to measure the thermal conductivity. As a result of the test, the thermal conductivity was 35 mW / mK.

≪ Example 2-2 >

Preparation of coating composition

Using the composite aerogels prepared in Example 1-2, coating compositions were prepared in the compositions shown in Table 2 below.

number designation Composition ratio (weight ratio) One Silica-carbon-titanium dioxide airgel 13.53 2 Micro cement 3.60 3 Half plaster 1.80 4 Silica fume 0.54 5 Fumed silica 0.13 6 lime 0.94 7 Calcium sulfoaluminate 0.31 8 Polyacrylic acid ester 4.58 9 Zinc phosphate 0.23 10 Talc 1.08 11 Potassium silicate 0.01 12 Magnesium oxide 0.06 13 Boric acid 0.23 14 Titanium dioxide 0.23 15 Silicone defoamer 0.09 16 Fiber (glass fiber, 2 mm) 0.01 17 Polyacrylamide 0.27 18 Polynaphthalene sulfonate 0.33 19 water 69.33 20 Polyurethane 2.70 100

The obtained coating composition of the present invention was produced in the form of a flat plate having a size of 25 cm in length, 25 cm in length, and 5 mm in thickness, and then dried to measure the thermal conductivity. As a result of the test, the thermal conductivity was 34.2 mW / mK.

≪ Comparative Example 1 &

In order to confirm the effect of the composite airgel produced according to the present invention on the thermal conductivity, a coating composition having the composition shown in Table 3 below was prepared as a control group for comparison with Example 2-1. A coating composition was prepared in the same manner as in Example 2-1, except that silica airgel was used instead of the composite airgel obtained in Example 1-1.

number designation Composition ratio (weight ratio) One Silica airgel 13.53 2 Micro cement 3.60 3 Half plaster 1.80 4 Silica fume 0.54 5 Fumed silica 0.13 6 lime 0.94 7 Calcium sulfoaluminate 0.31 8 Polyacrylic acid ester 4.58 9 Zinc phosphate 0.23 10 Talc 1.08 11 Potassium silicate 0.01 12 Magnesium oxide 0.06 13 Boric acid 0.23 14 Titanium dioxide 0.23 15 Silicone defoamer 0.09 16 Fiber (glass fiber, 2 mm) 0.01 17 Polyacrylamide 0.27 18 Polynaphthalene sulfonate 0.33 19 water 69.33 20 Polyurethane 2.70 100

The resulting coating composition was prepared in the form of a flat plate having a size of 25 cm in length, 25 cm in length and 5 mm in thickness, and then dried to measure the thermal conductivity. As a result of the test, the thermal conductivity was 39.44 mW / mK.

It can be confirmed that the thermal conductivity of the coating composition containing the composite airgel of the present invention is significantly improved as compared with the case of using the silica airgel.

≪ Comparative Example 2 &

The thermal conductivity of the coating composition using various heat insulating materials was tested, and the results were compared with the thermal conductivity of the coating composition of the present invention.

First, the thermal conductivity of a thermal insulation paint (manufactured by Samhwa), Korund, and an unshulse was used as a thermal insulation coating, and the thermal conductivity of each thermal insulation coating was measured to be 25 cm * 25 cm * 4 mm .

The thermal conductivity was measured at a thermal conductivity of 75.59 mW / mK, a corundum of 53.74 mW / mK, and an unstable rate of 84 mW / mK. The heat insulating coatings commonly used as described above had a significantly higher thermal conductivity than the coating compositions of the present invention (Examples 2-1 and 2-2) (i.e., the heat insulating performance was significantly lowered).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims (20)

A resin solution for coating formed of a liquid resin; A composite airgel which is formed in an integral bonding structure in which an infrared ray blocking material is embedded in a three-dimensional net structure forming a base material and is added in powder form to the resin solution for painting; Wherein the infrared shielding material is carbon, or carbon and titanium dioxide are compounded at a constant weight ratio. The method according to claim 1,
Wherein the base material is formed by using any one of silica, alumina, polyimide, silica-titania, silica-carbon, vanadia, zirconia and acetate cellulose which can be formed into an aerogel form. Composition. The method according to claim 1,
Wherein the carbon is one of graphite, carbon black, and activated carbon. The method according to claim 1,
The infrared blocking material may be added to the composite airgel 0.5 to 10% by weight, based on the total weight of the composition. The method according to claim 1,
Wherein the resin solution for coating is formed of any one selected from an acrylic resin, a silane resin, a siloxane resin, a phthalic acid resin, a vinyl chloride resin, an epoxy resin, a urethane resin and an aminoalkyd resin. The method according to claim 1,
Wherein the binder further comprises at least one binder selected from organic binders and inorganic binders. The method according to claim 6,
Wherein the binder comprises 30 to 90% by weight of an organic binder and 10 to 70% by weight of an inorganic binder. 8. The method according to claim 6 or 7,
Wherein the organic binder is at least one selected from the group consisting of a polyurethane, an acrylate copolymer, a polyacrylamide, and a polynattalenesulfonate. 8. The method according to claim 6 or 7,
Wherein the inorganic binder is at least one selected from the group consisting of micro cement, semi-gypsum, silica fume, fumed silica, lime, calcium sulfoaluminate, silicate, silica, zinc phosphate, talc and magnesium oxide. Composition. The method according to claim 1,
Fumed silica formed in nanoscale powder form; Silicone antifoaming agent; And at least one additive selected from fibers having a length of 0.1 to 4 mm. 11. The method of claim 10,
Wherein the fibers are at least one selected from the group consisting of polypropylene fibers, polyethylene fibers, silica fibers, alumina fibers, carbon fibers and glass fibers. Adding an infrared ray blocking material in powder form to a mixture of water and water, mixing the base material with water, adding carbon as the infrared ray blocking material, or adding carbon and titanium dioxide in a predetermined weight ratio and stirring, Adding a catalyst to form a composite airgel;
And adding the composite airgel to the resin solution for the paint in the form of a powder. 13. The method of claim 12,
Wherein the base material comprises a composite airgel-containing coating composition characterized by using any one of silica, alumina, polyimide, silica-titania, silica-carbon, vanadia, zirconia and acetate cellulose, Gt; 13. The method of claim 12,
Wherein the mixed liquid is prepared by mixing 10 to 50% by weight of the base material and 50 to 90% by weight of water. 13. The method of claim 12,
Wherein the carbon is formed in a powder form having a size of 0.1 to 50 mu m. 16. The method of claim 15,
Wherein the carbon is one of graphite, carbon black, and activated carbon. 17. The method according to any one of claims 12 to 16,
Wherein the infrared blocking material is added in an amount of 0.05 to 2 parts by weight based on 100 parts by weight of the mixed liquid. 13. The method of claim 12,
Wherein the titanium dioxide is formed in a powder form having a size of 300 to 500 nm. 13. The method of claim 12,
Wherein the composition is mixed at a ratio of 40 to 95% by weight of the resin solution for coating and 5 to 60% by weight of composite airgel. 13. The method of claim 12,
Further comprising the step of adding at least one binder selected from an organic binder and an inorganic binder to the coating composition at a weight corresponding to 5 to 50% by weight based on the total weight of the coating composition containing the composite airgel, A method for producing a coating composition.