KR20120050682A - Room temperature curing type water-soluable inorganic painting composition having excellent water-resistance and method for preparing the same - Google Patents

Abstract

PURPOSE: An ambient-temperature curable water-soluble inorganic paint composition is provided to be environment-friendly, and to have excellent water resistance, thereby extending the life time of coating even in case of being painted to concrete, iron, etc, which are frequently contact with moisture. CONSTITUTION: An ambient-temperature curable composition comprises: 100.0 parts by weight of a binder which is a mixture of water glass and water, and has the solid-phase content of 10-35%; 10-110 parts by weight of magnesium-containing compound, and 30-70 parts by weight of jade powder, or a mixture selected from 10-20 parts by weight of calcium hydroxide solution of 2-5% concentration, 20-70 parts by weight of silicon oxide powder, and 4-10 parts by weight of zinc oxide, or a mixture with at least one compound of the jade powder and the selected mixture.

Description

ROOM TEMPERATURE CURING TYPE WATER-SOLUABLE INORGANIC PAINTING COMPOSITION HAVING EXCELLENT WATER-RESISTANCE AND METHOD FOR PREPARING THE SAME

The present invention relates to a naturally-friendly water-soluble inorganic coating composition having excellent water resistance and a manufacturing method thereof, and more particularly, to a water-soluble inorganic coating composition having excellent water resistance mainly composed of water glass, such as liquid sodium silicate or liquid potassium silicate, and the preparation thereof. It is about a method.

According to the present invention, a coating composition mainly composed of water glass, such as liquid sodium silicate or liquid potassium silicate, can be easily produced, and the coating composition thus obtained is natural-friendly and excellent in water resistance, so that concrete or iron frequently contacts with moisture. Even if coated on the external appearance of the film, the life of the coating film can be extended.

Today, with the development of industry, organic chemical products are mass produced and their use is increasing. However, in the case of solvent-based paints and binders, a large amount of volatile organic substances are released, which is not only harmful to the human body but also causes pollution. In recent years, its use has been regulated.

However, many organic chemicals are still in use because newly developed products do not meet the consumer demand. Therefore, organic chemicals are still used in building materials such as interior wallpaper, flooring, and paint in apartments and buildings, and toxic chemicals such as formaldehyde and volatile organic compounds are released into the environment.

Recently, many studies have been conducted to solve the above problems. Korean Patent No. 0941997 relates to "inorganic aqueous binder having improved water resistance and inorganic aqueous paint using the same and a method of preparing the same", and a silicate mixture in which liquid sodium silicate, liquid potassium silicate, silica sol, water, and liquid lithium silicate are mixed. and; Natural cellulose fibers to prevent cracking of calcium hydroxide and metakaolin and coating film for water resistance, water tightness and surface strength, zinc oxide (ZnO) as a hardening agent and water resistant reinforcing agent in which copper sulfate, ferric sulfate and alum were dissolved in water, Fine powders such as activated quartz, activated calcium and ocher are used as inorganic reinforcing agents for the production of various pigment mixtures and anions and antibacterial deodorization in inorganic water-soluble binders in which calcium silica fluoride and sodium silica fluoride, a wetting agent, and an antifoam are mixed. Disclosed are an inorganic aqueous binder mixed at a predetermined ratio, an inorganic aqueous paint using the same, and a method of manufacturing the same.

In addition, Korean Patent No. 0937631 relates to "Method and Construction Method for Inorganic Coating Composition for Concrete", comprising the steps of: a) heating a predetermined colloidal silica to a predetermined temperature while mixing and stirring water; b) adding a mixed solution of potassium hydroxide, aluminum hydroxide and water to the elevated aqueous colloidal silica to stir to prepare a composite colloidal silica; c) adding and stirring organoalkoxysilane to the composite colloidal silica; And d) adding and stirring a fluorine-based surfactant is disclosed.

However, the Korean Patent No. 0941997 can prevent cracking of the coating film only by using natural cellulose, and the Korean Patent No. 0937631 requires the addition of an organoalkoxysilane when preparing a composite colloidal to obtain a water repellent function. Although it can be expected to improve the water resistance, the water resistance is lowered repeatedly in contact with water, there is a limit to the long life of the coating film.

Generally, the water glass of liquid sodium silicate or liquid potassium silicate is a material that is very suitable for forming paints because of its heat resistance and nature friendliness.However, since it has good affinity with polar water, it dissolves in water when repeatedly contacted with water. Have For this reason, its use is limited in an environment where water is frequently in contact.

Accordingly, the present invention is to provide a coating composition that can be prevented from cracking the coating even without using water for a long time in an environment where frequent contact with moisture, such as natural cellulose fibers.

In addition, the present invention is to provide a coating composition that does not melt even when hardened at room temperature and deposited in water and does not easily crack the coating.

The present invention provides, as a first aspect, a room temperature-curable water-soluble inorganic coating composition having excellent water resistance, and specifically, as a mixture of water glass and water, 100 parts by weight of a binder having a solid content of 10-35% by weight; 10-110 parts by weight of a magnesium containing compound; And i) 30-70 parts by weight of jade powder, ii) a mixture of two or more of 10-20 parts by weight of calcium hydroxide solution, 20-70 parts by weight of silicon dioxide powder and 4-10 parts by weight of zinc oxide, or iii) Provided is a room temperature curable water-soluble inorganic coating composition having excellent water resistance, comprising a mixture of the component of i) and at least one of the components of ii).

The water glass may be a liquid sodium silicate having a molar ratio of SiO ₂ / Na ₂ O of 2.3-3.6, a liquid potassium silicate having a molar ratio of SiO ₂ / K ₂ O of 1.3-4.6, or a mixture thereof, or a molar ratio of SiO ₂ / Na ₂ O Liquid sodium silicate having a molar ratio of 2.3-3.6, liquid potassium silicate having a molar ratio of SiO ₂ / K ₂ O, or a mixture thereof, and liquid lithium silicate having a molar ratio of SiO ₂ / Li ₂ O of 4.5 to 8.5 It may be a mixture of parts.

The magnesium-containing compound may be magnesium oxide, magnesium carbonate, magnesium hydroxide, light dolomite (CaOMgO), dolomite (CaMg (CO ₃ ) ₂ )), magnesium chloride or a mixture of two or more thereof.

In addition, the inorganic coating composition may further include 1-4 parts by weight of an antifoaming agent, 0.3-5 parts by weight of a viscosity modifier or a mixture thereof, and the viscosity modifier may be fumed silica.

Further, the inorganic coating composition may be a silver or zinc-containing zeolite-based inorganic antimicrobial agent; Humectants, including silica gel, kaolin, zeolite or mixtures thereof; Far-infrared radiation powder including loess, elvan or mixtures thereof; Anti-condensation and insulation, including perlite, vermiculite (vermiculite) or mixtures thereof; And at least one additive selected from the group consisting of anion generators of tourmaline.

Furthermore, the present invention provides, as a second aspect, a method for producing a room temperature-curable water-soluble inorganic coating composition having excellent water resistance, and specifically, water-containing binder having a water content of 10-35% by weight by mixing and stirring water in water glass. A step of preparing and 100 parts by weight of the water glass-containing binder, 10-110 parts by weight of a magnesium-containing compound and i) 30-70 parts by weight of jade powder; ii) a mixture of two or more of 10-20 parts by weight of a calcium hydroxide solution, 20-70 parts by weight of silicon dioxide powder and 4-10 parts by weight of zinc oxide; Or iii) mixing a mixture of at least one of the components of i) and the components of ii).

The water glass-containing binder was prepared by mixing 100 parts by weight of an alkaline silica sol having a solid content of 30-45% by weight and 30-50 parts by weight of water, heating and stirring to maintain a temperature of 60-90 ° C., and preparing a potassium sol solution. 30 parts by weight and 0.8-5 parts by weight of lithium hydroxide may be dissolved in 15-40 parts by weight of water, and then heated to 60-90 ° C. to add to the silica sol solution.

Preferably, the water glass may be composed of a liquid sodium silicate having a molar ratio of SiO ₂ / Na ₂ O of 2.3-3.6, liquid potassium silicate having a molar ratio of SiO ₂ / K ₂ O of 1.3-4.6, or a mixture thereof. More preferably, the water glass may further include a liquid lithium silicate having a molar ratio of SiO ₂ / Li ₂ O of 4.5 to 8.5.

The magnesium-containing compound is magnesium oxide, magnesium carbonate, magnesium hydroxide, light dolomite (CaOMgO), dolomite (CaMg (CO ₃ ) ₂ )), magnesium chloride or a mixture of two or more thereof.

The inorganic coating composition is an antifoaming agent 1-4 parts by weight; 0.3-5 parts by weight of viscosity modifier; And it may further comprise at least one selected from the group consisting of 0.5-3 parts by weight of silicone-based water repellent.

Further, the inorganic coating composition may be a silver or zinc-containing zeolite-based inorganic antimicrobial agent; Far-infrared radiation powder selected from loess, elvan and mixtures thereof; Humectants selected from silica gel, kaolin, zeolites and mixtures thereof; Anion generators of tourmaline; Anti-condensation and insulation selected from perlite, vermiculite and mixtures thereof; And It may further comprise at least one additive selected from the group consisting of a photocatalyst for deodorizing titanium dioxide.

Since the inorganic coating composition of the present invention shows excellent water resistance, even if applied to the surface of the building interior and exterior materials, concrete or metal which is frequently in contact with water, it is possible to prolong the life of the coating film.

In addition, the inorganic coating composition of the present invention is harmless to the human body and exhibits excellent heat resistance, so that it does not burn well during fire occurrence and does not generate soot, which is a secondary harmful substance due to fire, and thus can be suitably used as a fire protection paint.

Furthermore, when the inorganic coating composition of the present invention forms a coating film on the surface of concrete or the like, the coated film has an alkali property similar to the pH of the cement and has good adhesion to the cement to prevent peeling of the coating film. It can prevent.

The present invention provides a coating composition mainly containing water glass as a room temperature curing type water-soluble inorganic coating composition excellent in water resistance.

Water glass, which is the main ingredient of the paint composition provided in the present invention, may use sodium silicate-based or potassium silicate-based water glass, and is not particularly limited. Generally, commercially available water glass may be used, or water glass may be manufactured as needed. Can be used. Examples of preferred water-glass than in the present invention, a sodium silicate water glass may be used in a molar ratio of SiO ₂ / Na ₂ O 2.3-3.6. As the potassium silicate-based water glass, one having a molar ratio of SiO ₂ / K ₂ O of 1.3 to 4.6 can be used. In the present invention, the sodium silicate-based water glass and potassium silicate-based water glass may be used alone, or may be used by mixing them.

The water glass is mixed with water and used as a binder. In this case, the water glass and water mixture is preferably in the range of 10 to 35% by weight in consideration of the content of the following additional components. If the solid content concentration is less than 10% by weight, the solid content concentration of the binder is too low to dilute the coating composition, the workability is lowered, and when the solid content concentration is more than 35% by weight, the composition may be partially agglomerated to form a uniform coating film. It is preferable to mix in solid content concentration of the said range.

Further, the binder containing the water glass may further include lithium silicate-based water glass in addition to the sodium silicate-based water glass or potassium silicate-based water glass. In general, the lithium silicate-based water glass may be a mole ratio of SiO ₂ / Li ₂ O is 4.5 ~ 8.5. The lithium silicate-based water glass having such a high molar ratio has excellent water resistance, and may contribute to the improvement of water resistance and heat resistance of the coating film with respect to the composition of the present invention, but may be expensive and cause cracking of the coating film. It is preferable to use as little as possible, and when it is used, it is preferable to use it in the range of 5-30 weight part with respect to 100 weight part of binders which are a mixture of the said sodium silicate water glass or potassium silicate water glass and water. If less than 5 parts by weight, the effect of improving the water resistance and heat resistance due to the addition of lithium silicate is insignificant, and if it exceeds 30 parts by weight, the concentration of the coating composition is excessively high, resulting in a decrease in workability, rather causing an increase in price and cracking of the coating film. It is preferable to use it in the said range.

The inorganic coating composition of the present invention includes jade powder, silicon dioxide powder, calcium hydroxide solution, zinc oxide and the like in a water glass-containing binder for improving the physical properties of the paint composition.

The jade powder reacts with liquid sodium silicate or liquid potassium silicate in part to make the coating film strong and strong, and further smooth the surface of the coating film and smooth the appearance.

Table 1 shows representative jade components.

ingredient SiO ₂ MgO CaO Al ₂ O ₃ Fe ₂ O ₃ Na ₂ O K ₂ O Etc content(%) 55.5 25.5 12.3 1.4 0.7 0.3 0.1 4.2

The jade powder used in the present invention is preferably a particle size of 200 to 400 mesh. In the case where the particle size is larger than 200 mesh, the particles are large to roughen the surface of the coating film, and there is a problem in that the voids between the particles increase to decrease the strength of the coating film. Further, when the particle size is smaller than 400 mesh, the specific surface area is too large, the reaction rate is fast, and workability is inferior.

The jade powder is preferably included in the range of 30 to 70 parts by weight based on 100 parts by weight of the water glass-containing binder. If the content of the jade powder is less than 30 parts by weight, there is a problem that the strength of the coating film falls, and if the content of the jade powder exceeds 70 parts by weight, the inorganic content is too high, the viscosity is too high, and this causes the curing speed to increase, such as workability There is a problem of this deterioration.

The silicon dioxide powder not only improves the flowability of the liquid water glass composition, but also serves to improve the watertightness of the liquid water glass composition. The silicon dioxide powder may be included in the range of 20 to 70 parts by weight based on 100 parts by weight of the water glass-containing binder. If it is less than 20 parts by weight does not affect the flowability improvement, if it exceeds 70 parts by weight, there is a problem that the workability is lowered because the viscosity is too high because the content of inorganic matters.

The calcium hydroxide solution serves to improve water resistance to water by performing a pozzolanic reaction with SiO ₂ of water glass, and in particular, serves to improve adhesion when the adherend is concrete. The calcium hydroxide solution is preferably contained in a concentration of 2 to 5% solution in the range of 10-20 parts by weight, when less than 10 parts by weight, the curing speed is slow and there is a problem that the adhesive strength is lowered when the adhered surface is concrete, 20 weight When the amount is exceeded, there is a problem of poor dispersibility in the composition.

In addition, the zinc oxide serves to improve the dispersibility of various components in the liquid water glass inorganic coating composition. Furthermore, such zinc oxide also provides a side effect of providing a hiding power such that the color of the adhered surface is not exposed to the outside as white. Such zinc oxide may be included in an amount of 4-10 parts by weight based on 100 parts by weight of the water glass-containing binder. If it is less than 4 weight part, the dispersibility improvement effect will not be enough, and when it exceeds 10 weight part, there exists a possibility that the strength of a coating film may become weak.

These components are water glass inorganic coating compositions in the form of i) an jade powder or ii) a calcium hydroxide solution, a silicon dioxide powder and a mixture of two or more of zinc oxide or iii) a mixture of the components of i) and at least one of the components of ii). It can be included in.

The water glass inorganic coating composition of this invention contains a magnesium containing compound in order to provide water resistance to a coating film. The magnesium-containing compound reacts with SiO ₂ of the water glass to impart water resistance to water and to improve solution stability. Examples of the magnesium-containing compound include, but are not limited to, magnesium oxide, magnesium carbonate, magnesium hydroxide, light dolomite (CaOMgO), dolomite (CaMg (CO ₃ ) ₂ ), magnesium chloride (MgCl ₂ ), and the like. These may be added alone or in combination.

It is preferable to add the said magnesium containing compound in the range of 10-110 weight part with respect to 100 weight part of water glass containing binders. If the content of the magnesium-containing compound is less than 10 parts by weight, the water resistance is not sufficient, when the content of more than 110 parts by weight there is a problem that the cracking of the coating film is high due to the high content of the inorganic material. More preferably, it may contain 10 to 90 parts by weight, still more preferably 10 to 50 parts by weight.

Furthermore, the inorganic coating composition of the present invention may further include additives such as an antifoaming agent, a viscosity modifier, an antibacterial agent, a humectant, a far infrared radiation powder, an anion generator, an anti-condensation and heat insulating material, a water repellent, or a pigment.

The antifoaming agent included in the inorganic coating composition of the present invention suppresses the foaming of the coating composition, and is not particularly limited. For example, silica is contained in polymethyldisiloxane such as DB-110A of Dow Corning Corporation or KMK 73 of Shin-Etsu Corporation. The thing which emulsified the silicone compound containing is mentioned. It is preferable that the said antifoamer contains 1-4 weight part with respect to 100 weight part of water glass containing binders. If it is less than 1 part by weight, it is difficult to sufficiently obtain the antifoaming effect in the solution. If it exceeds 4 parts by weight, no increase in the effect due to the antifoaming agent can be obtained.

In addition, the inorganic coating composition of the present invention may include a viscosity modifier. Suitable viscosity modifiers include fumed silica (Degussa A200), which is similar in composition to the liquid silicic acid compound and improves liquid flow, and may include 0.3-5 parts by weight with respect to 100 parts by weight of the water glass-containing binder. Can be.

And, in order to improve the initial water resistance of the inorganic coating composition of the present invention may include a water repellent, the water repellent is not particularly limited, such as potassium methyl silicate such as Dow Corning 777 manufactured by Dow Corning, such as Polon-C of Shin-Etsu Silicone type water repellents, such as the thing which emulsified sodium methyl silicate or silicone oil, can be used. It is preferable to contain the said water repellent in the range of 0.5-3 weight part.

In addition, in the inorganic coating composition of the present invention, if it is necessary to suppress mold growth depending on the application, silver or zinc-containing zeolite-based inorganic antimicrobial agents that are harmless to the human body may be added, and far-infrared rays or anions may be generated from the coating film. In this case, far-infrared radiation powders such as calcined or unfired ocher or elvan can be added and anion generators of tourmaline.

In addition, when humidity control in the room is required, silica gel, kaolin or zeolite may be used as a humectant, and may further include a titanium dioxide-based photocatalyst for deodorization and odor removal, and is required to give an aesthetic appearance of the coating film. According to the present invention, the pigments commonly used may be added to impart color. Furthermore, it is also possible to add anti-condensation and heat insulating materials including perlite, vermiculite (vermiculite) or mixtures thereof.

As a 2nd viewpoint, this invention provides the normal temperature hardening type water-soluble inorganic coating composition manufacturing method excellent in water resistance.

Inorganic coating composition production method of the present invention comprises the steps of mixing 15-40 parts by weight of water to 60-100 parts by weight of water glass to prepare a water glass-containing binder having a solid content of 10-35% by weight; And 10-110 parts by weight of a magnesium-containing compound, based on 100 parts by weight of the water glass-containing binder. i) 30-70 parts by weight of jade powder or ii) 10-20 parts by weight of a calcium hydroxide solution at a concentration of 2-5%, a mixture of two or more of i) 20-70 parts by weight of silicon dioxide powder and 4-10 parts by weight of zinc oxide, or i) Adding a mixture of components with at least one of the components of ii).

In addition, the inorganic coating composition may include a physical property improving agent and additional additives.

The water glass of the water glass-containing binder is generally used commercially available water glass, as described above, the water glass is a liquid sodium silicate, SiO ₂ / K ₂ O ₃ molar ratio of 2.3-3.6 of SiO ₂ / Na ₂ O The molar ratio of may be made of a liquid potassium silicate or a mixture thereof, more preferably the water glass may further include a liquid lithium silicate having a molar ratio of SiO ₂ / Li ₂ O of 4.5-8.5.

In addition, the water glass containing binder of this invention can also be manufactured directly. In the case of preparing the binder, a silica sol solution is prepared by mixing 100 parts by weight of an alkaline silica sol having a solid content of 30-45% by weight and 30-50 parts by weight of water, maintaining the temperature at 60-90 ° C. by heating and stirring. 15-30 parts by weight of potassium and 0.8-5 parts by weight of lithium hydroxide may be dissolved in 15-40 parts by weight of water, and then heated to 60-90 ° C. to be added to the silica sol solution.

At this time, it is preferable that the silica sol used is alkaline, and solid content concentration is 30-40 weight%. On the other hand, the silica particles of the silica sol, the smaller the particle size, even if less potassium hydroxide can be dissolved SiO ₂ easily, thereby reducing the amount of potassium hydroxide added. Therefore, it is possible to increase the molar ratio of SiO ₂ / K ₂ O of water glass is obtained. It is preferable that the particle diameter of suitable silica is 10-30 nm in average diameter.

Furthermore, the inorganic coating composition of the present invention may further include additives such as an antifoaming agent, a silicone-based water repellent, a viscosity modifier, a humectant, an antibacterial agent, a far-infrared radiation powder, an anion generator, an anti-condensation agent, and a heat insulating material, a photocatalyst or a pigment. Can be.

These additives may be added during the preparation of the water glass-containing binder, and may be added together with the components for improving the physical properties after the water glass binder is prepared.

The additive is the same as the description of the inorganic coating composition, and the repeated description is omitted here.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, these examples are not intended to limit the scope of the invention.

[ Example ]

Example 1

30 parts by weight of water and 10 parts by weight of liquid lithium silicate having a molar ratio of SiO ₂ / Li ₂ O were added to 65 parts by weight of liquid sodium silicate having a molar ratio of SiO ₂ / Na ₂ O of 3.3 (COLITE-89SSS: manufactured by Cosmo Fine Chemical). Stirred for minutes to prepare a binder.

66 parts by weight of jade powder, 16 parts by weight of magnesium oxide and 6 parts by weight of zinc oxide were added to 100 parts by weight of the obtained binder, followed by stirring for 30 minutes , followed by 1 part by weight of an antifoaming agent (KMK 73 manufactured by Shin-Etsu Co., Ltd.). , 1.5 parts by weight of a water repellent (Dow Corning 777) and 1 part by weight of fumed silica (manufactured by A200 Degussa) as a viscosity modifier were stirred for 30 minutes to prepare a room temperature curable water-soluble inorganic coating.

Example 2

30 parts by weight of water was added to 65 parts by weight of liquid potassium silicate (Schemtec POSIL35) having a molar ratio of SiO ₂ / K ₂ O of 3.5 to prepare a binder.

63 parts by weight of jade powder pulverized to a particle size of 325 mesh, 15 parts by weight of magnesium oxide, 1 part by weight of titanium dioxide, 1 part by weight of an antifoaming agent (ShinEtsu KMK 73), a water repellent (Dow coating 777) 1.4 1 part by weight of fumed silica (A200: Degussa) was added as parts by weight and a viscosity modifier, followed by stirring for 30 minutes to prepare a room temperature curable water-soluble inorganic paint.

Example 3

Liquid lithium silicate with a molar ratio of SiO ₂ / Li ₂ O of 5 was added to 20 parts by weight of 65 parts by weight of liquid sodium silicate (COLITE-89SSS: manufactured by Cosmo Fine Chemicals) with a molar ratio of SiO ₂ / Na ₂ O of 10 Part by weight was added and stirred for 20 minutes. While the stirring was continued, 1.5 parts by weight of a water repellent (Dow Corning 777) was added while stirring for 30 minutes with 35 parts by weight of magnesium oxide, 5 parts by weight of dolomite, and 50 parts by weight of finely divided silicon dioxide powder and 5 parts by weight of zinc oxide. 15 parts by weight of a calcium hydroxide solution (5%), 1 part by weight of an antifoaming agent (ShinEtsu KMK 73), and 1 part by weight of fumed silica (A200: Degussa) were added as a viscosity modifier to prepare a room temperature curable water-soluble inorganic paint.

Example 4

25 parts by weight of water was added to 70 parts by weight of liquid potassium silicate (Schemtech POSIL 35) having a molar ratio of SiO ₂ / K ₂ O of 3.5 and stirred for 30 minutes. While stirring was continued, 35 parts by weight of magnesium oxide, 50 parts by weight of finely divided silicon dioxide powder and 5 parts by weight of zinc oxide were added and stirred for 30 minutes. While stirring, add 1 part by weight of antifoaming agent (ShinEtsu KMK 73), 1.5 parts by weight of water repellent (Dow corning 777), 15 parts by weight of calcium hydroxide solution (5% by weight) and 1 part by weight of fumed silica (A200: Degussa) as a viscosity modifier. Stirred for 30 minutes to prepare a room temperature curing type water-soluble inorganic paint.

Example 5

45 parts by weight of water was added to 100 parts by weight of an alkaline silica sol having a solid content of 30% by weight (average particle size of silica of 10 nm), and the mixture was heated and maintained at 70 ° C. 13.5 parts by weight of potassium hydroxide and 1.5 parts by weight of lithium hydroxide were dissolved in 20 g of water in the silica sol solution, and the mixture was added to the obtained silica sol solution and the stirring was continued until the solution dissolved transparently. Thus obtained 180 parts by weight of the transparent liquid lithium-potassium silicate was prepared.

1 part by weight of an antifoaming agent (ShinEtsu KMK 73) while stirring by adding 75 parts by weight of jade powder, 15 parts by weight of magnesium oxide and 1 part by weight of titanium dioxide, pulverized to a particle size of 325 mesh to 100 parts by weight of the liquid lithium-potassium silicate prepared above. 1 part by weight of fumed silica (A200: Degussa) was added as a viscosity modifier and stirred for 30 minutes to prepare a room temperature-curable water-soluble inorganic coating.

Example 6

45 parts by weight of water was added to 100 parts by weight of an alkaline silica sol having a solid content of 30% by weight (average particle size of silica of 10 nm), and the mixture was heated and maintained at 70 ° C. After dissolving 13.5 parts by weight of potassium hydroxide and 1.5 parts by weight of lithium hydroxide in 20 parts by weight of water in the silica sol solution, it was added to the obtained silica sol solution and stirring was continued until the solution dissolved transparently. Thus obtained 180 parts by weight of the transparent liquid lithium-potassium silicate was prepared.

1.5 parts by weight of a water repellent (Dow Corning 777) and 15 parts by weight of a calcium hydroxide solution (5%) were added to 100 parts by weight of the prepared liquid lithium-potassium silicate, followed by stirring for 25 minutes. Further, 30 parts by weight of magnesium oxide, 5 parts by weight of dolomite, 40 parts by weight of finely divided silicon dioxide powder with a particle size of 325 mesh, and 5 parts by weight of zinc oxide were added and stirred while adding 1 part by weight of antifoaming agent and fumed silica (A200: Degussa) as a viscosity regulator. 1 part by weight was added and stirred for 30 minutes to prepare a room temperature curing type water-soluble inorganic paint.

Comparative Example 1

25 parts by weight of water was added to 70 parts by weight of liquid potassium silicate (Schemtech POSIL 35) having a molar ratio of SiO ₂ / K ₂ O of 3.5 to prepare a binder. To 100 parts by weight of the obtained binder, 1.5 parts by weight of a water repellent (Dow corning 777), 15 parts by weight of calcium hydroxide solution (5%), 70 parts by weight of finely divided silicon dioxide powder and 5 parts by weight of zinc oxide were added to a particle size of 325 mesh. While stirring, 1 part by weight of an antifoaming agent (ShinEtsu KMK 73) and 1 part by weight of fumed silica (A200: Degussa) were used as a viscosity modifier, followed by stirring for 30 minutes to prepare a room temperature curable water-soluble inorganic coating.

Comparative Example 2

30 parts by weight of water and 10 parts by weight of liquid lithium silicate having a molar ratio of SiO ₂ / Li ₂ O were added to 65 parts by weight of liquid sodium silicate having a molar ratio of SiO ₂ / Na ₂ O of 3.3 (COLITE-89SSS: manufactured by Cosmo Fine Chemical). Stirred for minutes to prepare a binder.

70 parts by weight of jade powder pulverized to a particle size of 325 mesh, 8 parts by weight of magnesium oxide and 6 parts by weight of zinc oxide were added to 100 parts by weight of the obtained binder, followed by stirring, 1.5 parts by weight of a water repellent (Dow Corning 777), and an antifoaming agent (Shin-Etsu). KMK 73) 1 part by weight and 1 part by weight of fumed silica (manufactured by A200 Degu) were added as a viscosity modifier, followed by stirring for 30 minutes to prepare a room temperature curable water-soluble inorganic paint.

[Property evaluation]

In order to evaluate the physical properties of the coating film formed using the inorganic paints prepared in Examples 1 to 6 and Comparative Examples 1-2, a steel sheet (150 mm × 70 mm × 1.2 mm) and a concrete plate (100 mm × 100 mm × 30) Mm), each coating was sprayed three times to form a coating film, and then dried at room temperature (25 ° C) for two days. The dry coating films formed on the steel sheet and the concrete sheet were 30 µm and 100 µm, respectively.

With respect to the obtained coating film, physical properties of water resistance, adhesion strength, washing resistance, saline resistance, base resistance and pencil strength were tested. Each test method was performed based on the following standard test method.

Water resistance: KSM ISO 2812-1 (immersion 240hrs)

Bond Strength: Pull-Off Strength Test Method (Cement: Surface Curing), Unit kgf / ㎠

Wash resistance: KSM 5000-3351

Saline resistance: KSM ISO 2812-2 (10% NaCl, 240hrs)

Base resistance: KSM 5307 (168hrs, 5% NaOH)

Pencil Strength: Pencil Hardness Tester (manufactured by Mitsubishi)

Water resistance, wash resistance, saline resistance and base resistance were visually examined. The change of state was evaluated as% of the changed area with respect to the total area of the coating film, and was determined based on the following criteria. The evaluation results are shown in Table 2.

◎: When the state of the coating film does not change

(Circle): When a coating film state changes for more than 0 and less than 20% of the total surface area.

X: When the coating film state changes more than 20% of the total surface area

Example Water resistance Bond strength Wash resistance Saline resistance Base resistance Pencil hardness Example 1 cement ◎ (0%) 27.2 ◎ (0%) ◎ (0%) ◎ (0%) 9H Steel sheet ◎ (0%) 29.7 ◎ (0%) ◎ (0%) ◎ (0%) 9H Example 2 cement ◎ (0%) 28.5 ◎ (0%) ◎ (0%) ◎ (0%) 8H Steel sheet ◎ (0%) 30.4 ◎ (0%) ◎ (0%) ◎ (0%) 8H Example 3 cement ○ (5%) 26.7 ◎ (0%) ○ (7%) ○ (5%) 9H Steel sheet ○ (6%) 27.5 ◎ (0%) ○ (7%) ○ (5%) 9H Example 4 cement ○ (6%) 27.1 ○ (8%) ○ (7%) ○ (6%) 8H Steel sheet ○ (6%) 27.6 ○ (8%) ○ (8%) ○ (7%) 8H Example 5 cement ◎ (0%) 30.2 ◎ (0%) ◎ (0%) ◎ (0%) 9H Steel sheet ◎ (0%) 32.2 ◎ (0%) ◎ (0%) ◎ (0%) 9H Example 6 cement ◎ (0%) 28.3 ◎ (0%) ◎ (0%) ◎ (0%) 9H Steel sheet ◎ (0%) 29.7 ◎ (0%) ◎ (0%) ◎ (0%) 9H Comparative Example 1 cement X (100%) 14.6 X (100%) X (100%) X (100%) 5H Steel sheet X (100%) 13.9 X (100%) X (100%) X (100%) 5H Comparative Example 2 cement × (50%) 20.5 × (45%) × (57%) × (62%) 6H Steel sheet × (50%) 19.3 × (48%) × (162%) X (65%) 6H

As can be seen from Table 2, in the case of Example 5 in which the silica sol was dissolved to make a binder, and the jade powder and magnesium oxide were mixed, excellent results were obtained in all of water resistance, wash resistance, and base resistance, and adhesion strength. And pencil hardness also yielded the best results.

Example 3 and Example 4, which were replaced with silicon dioxide, calcium hydroxide, and zinc oxide instead of jade powder, showed less water resistance, saline resistance, and basic resistance than jade powder, but showed good results. In the case of, it showed excellent results in terms of washing resistance.

In addition, in Examples 1 to 6, there was no cracking phenomenon on the coating film.

On the other hand, Comparative Example 1 does not include the magnesium oxide of Example 4, except that the content of silicon dioxide is increased, but it can be seen that does not exhibit any water resistance, Comparative Example 2 is magnesium oxide with Example 1 It is found that the content is outside the scope of the present invention and that the jade powder content is increased, but also the water resistance is remarkably inferior.

On the other hand, it can be seen that both the examples and comparative examples show that the cement has a slightly larger adhesion strength than the steel sheet, which is due to Ca's pozzolanic bond with SiO ₂ .

Claims (14)

100 parts by weight of a binder having a water content of 10-35% by weight as a mixture of water glass and water; 10-110 parts by weight of a magnesium containing compound; And i) 30-70 parts by weight of jade powder, ii) a mixture of two or more of 10-20 parts by weight of calcium hydroxide solution, 20-70 parts by weight of silicon dioxide powder and 4-10 parts by weight of zinc oxide, or i) A water-resistant curable water-soluble inorganic coating composition having excellent water resistance, comprising a mixture of a component of and a component of at least one of the components of ii). The method of claim 1, wherein the water glass is liquid silicon silicate having a molar ratio of SiO ₂ / Na ₂ O of 2.3-3.6, liquid potassium silicate having a molar ratio of SiO ₂ / K ₂ O of 1.3-4.6, or a mixture thereof. The room temperature hardening type water-soluble inorganic coating composition excellent in water resistance. The liquid glass of claim 1, wherein the water glass is liquid silicon silicate having a molar ratio of SiO ₂ / Na ₂ O of 2.3-3.6, liquid potassium silicate having a molar ratio of SiO ₂ / K ₂ O of 1.3-4.6, or a mixture thereof and SiO ₂ / Li ₂ O mole ratio is 4.5 ~ 8.5 in liquid lithium silicate 5 to excellent water resistance, characterized in that a mixture of 30 parts by weight of a room temperature curing of water-soluble inorganic coating composition. The magnesium-containing compound according to any one of claims 1 to 3, wherein the magnesium-containing compound is magnesium oxide, magnesium carbonate, magnesium hydroxide, light dolomite (CaOMgO), dolomite (CaMg (CO ₃ ) ₂ )), magnesium chloride or their It is a mixture of two or more, room temperature hardening type water-soluble inorganic coating composition excellent in water resistance. The inorganic paint composition according to any one of claims 1 to 3, further comprising 1-4 parts by weight of an antifoaming agent, 0.3-5 parts by weight of a viscosity modifier, 0.5-3 parts by weight of a silicone water repellent or a mixture thereof. The room temperature hardening type water-soluble inorganic coating composition excellent in water resistance characterized by the above-mentioned. The room temperature-curable water-soluble inorganic coating composition excellent in water resistance according to claim 5, wherein the viscosity modifier is fumed silica. The inorganic coating composition according to any one of claims 1 to 3, wherein the inorganic coating composition comprises a silver or zinc-containing zeolite-based inorganic antimicrobial agent; Far-infrared radiation powder selected from loess, elvan and mixtures thereof; Humectants selected from silica gel, kaolin, zeolites and mixtures thereof; Titanium dioxide photocatalysts; Anti-condensation and insulation selected from perlite, vermiculite and mixtures thereof; And at least one additive selected from the group consisting of anion generators of tourmaline. Mixing water with water and stirring to prepare a water glass-containing binder having a solid content of 10-35% by weight; And
10-110 parts by weight of a magnesium-containing compound, based on 100 parts by weight of the water glass-containing binder; And i) 30-70 parts by weight of jade powder; ii) a mixture of at least two of 10-20 parts by weight of a calcium hydroxide solution, 20-70 parts by weight of silicon dioxide powder and 4-10 parts by weight of zinc oxide; Or mixing a mixture of the component of i) and at least one of the components of ii). The method of claim 8, wherein the water glass-containing binder
Preparing a silica sol solution by mixing 100 parts by weight of an alkaline silica sol having a solid content of 30-45% by weight and 30-50 parts by weight of water, and heating and stirring to maintain the temperature at 60-90 ° C .; And 15-30 parts by weight of potassium hydroxide and 0.8-5 parts by weight of lithium hydroxide are dissolved in 15-40 parts by weight of water, and then heated to 60-90 ° C. to be added to the silica sol solution. Room temperature curing type water-soluble inorganic coating composition excellent in water resistance. The method of claim 8, wherein the water glass is a liquid sodium silicate having a molar ratio of SiO ₂ / Na ₂ O is 2.3-3.6, liquid potassium silicate having a molar ratio of SiO ₂ / K ₂ O is 1.3-4.6 or a mixture thereof. The normal temperature hardening type water-soluble inorganic coating composition manufacturing method which is excellent in water resistance. The method of claim 10, wherein the water glass further comprises liquid lithium silicate having a molar ratio of SiO ₂ / Li ₂ O of 4.5 to 8.5. The compound of claim 8, wherein the magnesium-containing compound is magnesium oxide, magnesium carbonate, magnesium hydroxide, light dolomite (CaOMgO), dolomite (CaMg (CO ₃ ) ₂ )), magnesium chloride or It is a mixture of two or more, The manufacturing method of the normal temperature hardening type water-soluble inorganic coating composition excellent in water resistance. According to any one of claims 8 to 11, wherein the inorganic coating composition is an antifoaming agent 1-4 parts by weight; 0.3-5 parts by weight of viscosity modifier; And 0.5-3 parts by weight of a silicone-based water repellent, further comprising at least one selected from the group consisting of water-resistant curable water-soluble inorganic coating composition excellent in water resistance. The inorganic coating composition according to any one of claims 8 to 11, wherein the inorganic coating composition comprises a silver or zinc-containing zeolite-based inorganic antimicrobial agent; Far-infrared radiation powder selected from loess, elvan and mixtures thereof; Humectants selected from silica gel, kaolin, zeolites and mixtures thereof; Anion generators of tourmaline; Anti-condensation and insulation selected from perlite, vermiculite and mixtures thereof; And A method for producing a room temperature-curable water-soluble inorganic coating composition excellent in water resistance, further comprising at least one additive selected from the group consisting of a photocatalyst for deodorizing titanium dioxide.