JPH06116512A - Production of low-temperature curable inorganic coating agent and method for forming low-temperature curable inorganic coating layer - Google Patents

Abstract

PURPOSE:To provide a low-temperature curable inorganic coating agent and a coated layer having excellent coating strength, weather resistance, acid resistance, stain resistance, water resistance, chemical resistance, abrasion resistance, luster and light-reflectance and useful for the surface-coating of a substrate such as metal, ceramic, concrete and glass. CONSTITUTION:The coating agent is produced by successively mixing 100 pts.wt. of fine silicon powder with 4,000-600 ptswt. of an alkali silicate, 8,000-2,000 pts.wt. of water, 10-1 pt.wt. of smectite powder, 30-3 pts.wt. of zinc oxide and <=10 pts.wt. of lithium aluminosilicate powder and one or more compounds selected from alumina, zirconia and silicon oxide, crushing and mixing the mixture to obtain a mixed liquid, adding 600-50 pts.wt. of an aqueous solution containing 20-0.5wt.% of one or more kinds of water-soluble compounds of lithium, potassium, barium, strontium or cesium and thoroughly stirring and mixing the product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a coating agent and a method for forming a coating layer, and particularly to a substrate surface of metal, ceramic, cement / concrete, glass or the like which is strong and has weather resistance, acid resistance and stain resistance. A method for forming a low temperature curing type inorganic coating layer having excellent water resistance, chemical resistance and abrasion resistance, and having multicolor and gloss properties and excellent light reflectivity, and a coating agent used in the method. The present invention relates to a manufacturing method.

[0002]

2. Description of the Related Art In conventional coating agents, (1) enamel glaze is mentioned as a general low-grade glaze. Lead compounds and borosilicate glass are used for this enamel glaze. These glazes are applied to the surface of a metal or ceramic material and usually melt at 700 to 850 ° C. to form a coating layer. The application has been conventionally known as a bathtub or a decoration as a cloisonne, and has recently been developed and used as a surface coating material for exterior materials as a measure against acid rain. (2) As the glaze used on the surface of ceramics and tiles,
There has been a glaze made mainly of silicate minerals for a long time, and it is vitrified at a firing temperature of around 1200 ° C to form a firm film, or a glaze is attached to the surface of the base material and the glaze is attached. There is a method of firing to vitrify. (3) As the organic paint, acrylic, epoxy, polyurethane type, etc. are used. All of these are two-part liquids, and are attached to the surface protected by moisture absorption with an organosilicon-based (organosilane-based oligomer) or styrene monomer for 2 to 3 times under normal humidity or low temperature heating. To form a coating layer. (4) In addition to the above (1) to (3), various low-temperature curing type one-component exchangeable coating agents have recently been marketed, but all of them use organic solvents such as alcohols and ethyl acid resistant solvents. It is a coating agent using a solvent.

However, the above conventional products have many technical and economic defects as follows. (1) As the standard firing temperature of enamel glaze, steel plate enamel is generally 800 to 850 ° C., cast iron enamel 900 to 9
The temperature is 50 ° C, and the aluminum enamel is 500 to 550 ° C. Today, there is a great demand for acid resistance and large exterior materials, and most of the substrate materials are limited to the use of stainless steel, but the surface contamination problem has been occurring after a few years. Furthermore, it is indispensable to install equipment and wastewater treatment measures for lead glazing during glazing, and to treat and dispose of lead glaze after the work, which requires a lot of expense. In addition, there is concern about the elution of lead from the coating film on the exterior material. On the other hand, when this lead glaze is used as a ceramic material, it is accompanied by cracks and it is difficult to manufacture a large-sized ceramic substrate material in modern times. Since stone materials cannot be heat treated, the materials used are extremely limited. (2) The glaze mainly made of common silicate minerals is 1,2
Since it requires heating at around 00 ° C, the manufacturing equipment is extremely expensive. At present, it is difficult to use ceramics for large plates. Further, application to metals, stone materials, and glass has many problems such that it cannot be used because of high firing temperature. (3) Organic paints are accompanied by industrial hygiene problems due to organic solvents during attachment work, and are generally burned at a temperature of 200 ° C or higher with respect to fire, and organic polymers and some solvents generate toxic gas. When forming the coating layer, about 2-3 layers are attached together with the base material, so 3,000
It is hard to say that it is a low-priced paint because it costs about ¥ / m ² . (4) Inorganic coating agents that have recently begun to be marketed use a solvent when used. Many of these solvents are generally based on organic substances, and the selling price is 20,000 yen / 30,000.
l and very expensive. Moreover, as a result of the treatment at 300 ° C. for 30 minutes, the surface strength is in the range of H to 9H, and the scratch strength is small. Further, since the solvent is alcohol, ethyl acetate or the like, it is volatilized when the coating layer is formed, so that the working environment is bad and the equipment cost for the treatment is increased.

As a result of intensive studies to solve the above problems, the present inventor has completed an invention that solves all of these defects. That is, the coating agent according to the present invention comprises (1) a complete inorganic substance containing no organic matter,
Since the solvent is water, it is odorless and harmless only by dehydration during drying and heating, and (2) the temperature for forming the coating layer is as low as room temperature to 500 ° C. (particularly preferably 150 to 300 ° C.), 3) The coating layer hardness can secure 2 to 6 (Mohs hardness), and (4) it has excellent weather resistance, acid resistance, water resistance, chemical resistance, abrasion resistance, heat resistance, and coated oil-based magic It can be easily erased by wiping with a solvent, and if this coating agent is colored with titanium oxide or iron oxide, a coating layer having various colors can be obtained. Further, (5) the coating agent can be freely applied on the substrate by spraying or brushing, and the same coating agent can be applied several times, and generally 2 to 3 times. Film thicknesses of 50-100 microns are obtained. Furthermore, the adhesive strength is high. (6) As the material for the substrate to be coated, all materials other than organic polymer materials, which are mainly composed of metal (iron, stainless steel, aluminum, etc.), ceramics, cement, concrete, stone material, glass, etc., can be used. (7) The manufacturing cost of the coating agent is as low as 500 to 1,000 yen / kg, and the amount of coating layer per time is 600 g to 1 kg / m ² . As described above, the new coating agent with excellent properties and its application,
We succeeded in developing the coating layer formation by drying and heating.

That is, according to the present invention, (1) an alkali silicate (for example, sodium silicate and / or potassium silicate) 4,000 to 600 is added to 100 parts by weight of silicon fine powder.
Parts by weight (preferably 2,000 to 1,000 parts by weight)
And 8,000 to 2,000 parts by weight of water (preferably,
Add 5,000 to 3,000 parts by weight) and stir well.
Zinc oxide is added to the first step in which 10 to 1 parts by weight (preferably 8 to 2 parts by weight) of smectite powder is mixed and sufficiently pulverized and mixed, and the mixed solution obtained in the first step is mixed. 30 to 3 parts by weight (preferably 20 to 5 parts by weight) is added, and one or more of alumina, zirconia or silicon oxide and 10 parts by weight or less (preferably 5 to 1 parts by weight) of lithium aluminosilicate powder are further added. In addition to the second step of pulverizing and mixing again, and the mixed liquid obtained in the second step,
An aqueous solution containing 20 to 0.5% by weight (preferably 15 to 1% by weight) of one or more water-soluble compounds of lithium, calcium, barium, strontium or cesium is used.
A third step of adding 0 to 50 parts by weight (400 to 100 parts by weight) and thoroughly stirring and mixing, and drying and heating at room temperature to 500 ° C (preferably 150 to 300 ° C). A method for producing a low-temperature-curable inorganic coating agent which produces a strong coating layer by the method, and

(2) 4,000 to 600 parts by weight (preferably 2,000 to 1,000 parts by weight) of alkali silicate (for example, sodium silicate and / or potassium silicate) per 100 parts by weight of silicon fine powder. And water 8,000
To 2,000 parts by weight (preferably 5,000 to 3,0)
00 parts by weight) and sufficiently agitated and mixed, and 10 to 1 parts by weight (preferably 8 to 2 parts by weight) of smectite powder is added thereto, and sufficiently pulverized and mixed; 30 to 3 parts by weight of zinc oxide (preferably 20 to 5 parts by weight) is added to the mixed solution obtained in the first step, and then alumina,
A second step of adding one or more of zirconia or silicon oxide and 10 parts by weight or less (preferably 5 to 1 parts by weight) of powder of lithium aluminosilicate, and pulverizing and mixing again, and a mixed solution obtained in the second step And 20 to 0.5% by weight (preferably 15%) of one or more water-soluble compounds of lithium, calcium, barium, strontium or cesium.
~ 1 wt%) containing 600 to 50 parts by weight of an aqueous solution (4
(3) Add 100 to 100 parts by weight) and thoroughly stir and mix
After applying the mixed liquid obtained in the step and the third step to the surface of the substrate such as metal, ceramic, cement / concrete, stone, glass, etc., the temperature is room temperature to 500 ° C. (preferably 150 to
And a fourth step of drying and heating at 300 ° C.), which is a method for forming a low-temperature-curable inorganic coating layer. In the above, it is also preferable to add and mix a fine powder of a pigment such as iron oxide or titanium oxide (for example, a commercially available inorganic pigment having a particle size of 0.5 μm or less) to the coating agent. Layers can also be formed.

Next, the outline of the mechanism of action such as the reaction between the raw materials used in the present invention will be described. (1) Generally, there are many unresolved reactions between a semi-metal / semiconductor material such as silicon and an alkaline solution, but silicon generates hydrogen in an alkaline hydroxide solution to generate metasilicate ions. According to the present invention, the alkali hydroxide solution in the first step is formed by pouring alkaline silicate water. This alkali hydroxide solution reacts with the silicon fine powder to promote the formation and promotion of silicate hydrates and their gels, and at the same time generate hydrogen gas. The X-ray diffraction pattern of the gel coating layer formed by the reaction between the silicon and the alkali silicate is almost amorphous as shown in FIG. In this step, smectite is mixed in an alkaline solution containing the gel produced by the above reaction, and then sufficiently pulverized and mixed. That is, if pulverization and mixing are sufficiently carried out, smectite takes on an extremely fine spherical state. The reaction product generated in the first step surrounds this spherical periphery, and it is possible to prevent thermal expansion and perform stable curing in a low temperature range. Further, the occurrence of cracks between grain boundaries that occur during drying and heating is not recognized from the results of observation by the coating layer formation experiment. The formation of new crystals is recognized by the heating change of this silicon-alkali silicate-smectite system. The crystals are poorly identified, but some appear to exist to the end. The state of this crystal formation is shown in FIG.

(2) In the second step, since the zinc oxide compounded in this solution is formally Zn _{1 + δ} O,
It indicates that zinc oxide is present in excess of _{δ with} respect to oxygen. It has not been studied whether this excess is due to the defect of oxygen atoms on the crystal lattice, whether Zn atoms excessively enter into the lattice, or both of them. However, after blending zinc oxide with this alkaline solution, it is activated by the mechanochemical effect of crushing and mixing and the thermal action of drying and heating, and plays the role of a network-modifying component for the cross-linking action as well as adhesion at low temperature. It is considered that functional effects and water resistance functions are exhibited. Although this is not fully clarified as a reaction mode, it is judged from the result of the physical property test of the final coating layer.

Next, one or more of alumina, zirconia and silicon oxide and a fine powder of lithium aluminosilicate (eg spongemen, petalite, eucryptite, etc.) as a substrate are added to this gel-like aqueous solution to form these substrates. The four circumferences of the particles are also surrounded by a gel-like substance in a very thin layer almost uniformly, and some of them act to form a mesh and play a role of imparting low expansion. Further, by controlling the amount of the gel solution to be as small as possible and increasing the compounding ratio of the substrate, the heating temperature at the time of forming the coating layer can be increased, and the upper limit is 500 ° C, preferably 300 ° C. The blending ratio can be adjusted as described above. On the other hand, in order to achieve the formation of the coating layer at room temperature to around 150 ° C., the amount of the gel-like solution in the four rounds of the substrate may be increased.

With such a composition, the temperature is from room temperature to 500 ° C.
It becomes possible to form a strong coating layer in the drying / heating temperature range (preferably 300 ° C.). As a result, new crystals are generated as shown in FIG. This result shows that K-Na-Si-O, Na-AL-Si-
In addition to the O-shaped crystals, the presence of added titanium oxide, alumina, and zirconia crystals is shown. On the other hand, the surface gloss of the coating layer is slightly reduced when cured near room temperature,
The coating layer can be formed by adjusting the hydrogen ion concentration on the surface with a weak acid. Oxalic acid is preferably applied as the weak acid in this case, but the hydrogen ion concentration on the surface is preferably in the range of about 10-11. (3) By mixing an inorganic pigment of titanium oxide or iron oxide as a coloring material with the mixed solution obtained in the second step, various colors of white to black can be produced. Generally, the average particle size of the inorganic pigment is 0.5 micron or less, and the particle shape is spherical, needle-shaped, or dice-shaped.
When crushing and mixing, perform sufficient operation so that the shape becomes almost spherical. By doing so, the substrate in the coating agent can be smoothly coated by dynamically rolling on the surface of the substrate material, and since the coating agent has a viscosity that easily forms a free surface, the film thickness is average. Formed. The viscosity at this time is preferably in the range of 1,000 to 1,700 cps in the case of brush and in the range of 200 to 1,000 cps in the case of spray.

Next, a saturated solution of lithium, calcium, barium, or a hydroxide, carbonate or oxalate of strontium or cesium, is added to the mixed solution of the colorant, and the mixture is further thoroughly mixed. The additive serves as a network modifying component and also serves to reduce viscosity and promote melting. Therefore, in terms of phenomena, the viscosity obviously decreases upon addition. Although the degree of this decrease depends on the amount of the saturated solution added, the result of addition and mixing is 300 to 1,20.
It is within the range of 0 cps, and the attached conditions are satisfied. The coating agent solution that has been manufactured in this way can be sprayed or brushed onto the substrate material such as metal, ceramic, cement,
It is applied to the surface of concrete, stone material, glass or the like, and a strong coating layer is formed by drying and heating at 500 ° C. or lower (preferably 300 to 150 ° C.), which has high surface hardness and exhibits various excellent physical properties. As a result, as shown in FIG. 10, almost the same crystalline substance as in FIG. 9 is produced, but it is considered that the added lithium ions and the like act as a network modifying component. That is, it is judged that the surface gloss is increased macroscopically, and in addition, as a result of the test, in this system, the surface hardness is further increased and the hot water resistance is excellent.

Here, the reason for limiting each numerical range in the above-mentioned constitution of the present invention will be explained. Although the compounding ratio of each raw material of the coating agent is related to each other, the limit of the compounding ratio should be strictly defined. Is difficult (1) In general, the reaction between silicon and alkali silicate is exemplified by the reaction formulas that can be considered. When the alkali silicate is sodium silicate, the ratio of silicon to sodium silicate is about 1: 4.4 parts by weight. About 1.5 for potassium
Parts by weight. However, the behavior of alkali silicate is complicated by the addition of water at this time, and it is said that the same hydrolysis as a concentrated alkali silicate solution and a dilute solution does not occur, and its details are an unsolved problem. Therefore, in the present invention, the addition amounts of silicon, alkali silicate and water are determined by the viscosity after the reaction. Also, it is determined by the phase relationship between the silicon and the viscosity of the solution in which the reaction product of the sodium silicate solution is dissolved, and the viscosity depends on the addition amount of various raw materials after the smectite mixing step and the coating layer of the target coating agent. After conducting various experiments from the results of formation, quantitative confirmation was performed by comprehensive judgment. That is, when the amount of silicon is 100 parts by weight, it is slightly more than 1,000 parts by weight when the alkali silicate is sodium silicate No. 1 (JIS), and is 2.0% in the case of sodium silicate.
It is preferable that the amount is slightly smaller than 00 parts by weight. On the other hand, when the alkali silicates are sodium silicate and potassium silicate, the former is preferably 350 parts by weight and the latter is preferably around 1,600 parts by weight. That is, if the amount of sodium silicate is more than the above amount, the water resistance of the coating film is weakened by heating, and if it is less, the reaction with silicon is not sufficiently performed. The same can be said for potassium silicate. Therefore, in any case, the total amount of alkali silicate is 4,000 to 600 parts by weight, preferably 2,000 to 1,
000 parts by weight is a suitable range. On the other hand, there may be a reaction in which the amount of water added is considered to be 3 parts by weight of water with respect to 1 part by weight of silicon. A sufficient dilute solution of alkali silicate is desirable. For this purpose, it is desired that the above-mentioned reaction vessel is an open type and the amount of water added until the end of the reaction is 5,000 to 3,000 parts by weight. As a result of such an experiment, the target viscosity is in the range of 50 to 30 cp, and the subsequent operation is sufficiently and satisfactorily performed.

(2) As the smectite fine powder, it is preferable to mainly use a hydrophilic type of synthetic smectite. This smectite has poor crystallinity, and its state is shown in FIG. Smectite is a clay mineral having an irregular thin plate shape with unclear edges and has a large ion exchange capacity and swelling degree. Among these, montmorillonite, beidellite and saponite are included.
te), hectorite, and the like. If the amount of such smectite added is more than 8 parts by weight, the viscosity becomes 300 cps or more after crushing and mixing, and the post-process is not smooth and the surface hardness is not sufficient when the coating layer is formed. . On the other hand, when the amount is less than 1 part by weight, it takes time to form the coating layer and it is difficult to sufficiently dry the coating layer. Particularly, 6 to 2 parts by weight is preferable. (3) Addition of a large amount of zinc oxide of 30 parts by weight or more has almost no effect on the role of the network-modifying component of the cross-linking effect. Rather, heating causes precipitation of zinc oxide and adversely affects the physical properties of the coating layer. Cause. On the other hand, addition of 3 parts by weight or less does not cause the above-mentioned various effects sufficiently, resulting in weakened viscosity and water resistance. Particularly, 20 to 5 parts by weight is preferable. In general, the added zinc oxide has a crystal structure as shown in FIG.

(4) One or more of alumina, zirconia, silicon oxide, and fine powder of lithium aluminosilicate (for example, spongemen) are mixed mainly as a substrate, and the chemical durability and low resistance of the coating layer formed are low. Helps to impart expandability. When the total amount of and is added in excess of 10 parts by weight, the heating temperature is 500 ° C.
It goes over to the high temperature side, and the coating layer lacks the bright property. On the other hand, when these are not contained, the coefficient of expansion of the coating layer increases, which causes cracks. The crystal structures of these alumina, silicon oxide, and sponge are common, but normally used zirconia is a synthesized one, and its structure has high crystallinity as shown in FIG. (5) The amount of pigment such as acidic titanium and iron oxide added is determined by the type of color tone and the shades thereof, and the quantitative ratio is not constant. For example, white is mainly mixed with titanium oxide, and black is mainly mixed with iron oxide. Further, the color between white and black is mainly iron oxide, and is composed of a compound containing silicon oxide and aluminum oxide. Generally, the amount of these pigments added is preferably 3 parts by weight or more as a result of experiments. The X-ray diffraction pattern of titanium oxide added here has good crystallinity as shown in FIG.

(6) Lithium, calcium, barium,
The addition amount of a solution containing 20 to 0.5% by weight of one or two kinds of strontium or cesium compounds is generally 600 to 50 parts by weight, preferably 400 to 100 parts by weight, and a coating layer even if 600 parts by weight or more is added. No change in hardness was observed, and rather the viscosity of the aqueous solution was lowered and it was difficult to sufficiently attach the coating solution in a dilute solution when forming the coating layer. If the solution is 50 parts by weight or less, the viscosity is too high when forming the coating layer, which makes attachment difficult and also makes it difficult to form a uniform coating thickness.
It is difficult to form a free water surface. Further, the result is that the water resistance of the coating layer is weak after the coating layer is formed. Thus, for example, at room temperature, about 13 g of lithium hydroxide is added to 10 parts of water.
What dissolved 0g and what melt | dissolved 15g of barium hydroxide baking in water are added to the mixed solution obtained at the 2nd process, and are mixed sufficiently, and a coating agent is produced. Also, at room temperature, about 13 g of lithium hydroxide dissolved in 100 g of water and about 6 g of barium hydroxide dissolved in 100 g of water are separately added as a network modifying component to perform a sufficient and firm coating. The layers are formed. Furthermore, when adding one or two solutions of calcium hydroxide, strontium oxalate, cesium oxalate, or cesium carbonate dissolved in about 100 g to 400 g, respectively, as in the case of lithium hydroxide or barium hydroxide solution. Manipulate. The X-ray diffraction of the representative lithium oxide added in this way exhibits very good crystals as shown in FIG.

(7) The coating amount of the solution for forming the coating layer is generally about 600 to 1,000 g / m ₃ . The difference in this case is different between the spray coating method and the brush coating method depending on the concentration of the solution, and the solution consumption amount by the former method is smaller than that by the latter method. 1 by this coating method
Since 30 to 50 microns of coating is formed each time,
Due to the physical properties of the coating layer, the final applied thickness is approximately 80-
In order to set the thickness to around 100 μm, it becomes possible to form a coating layer having a required thickness in a few coating steps.

[0017]

EXAMPLES Next, a method for producing a low temperature curable inorganic coating agent according to the present invention and a coating layer formed by using the obtained coating agent will be specifically described below with reference to examples. Example 1: To 100 parts by weight of silicon fine powder, 1,200 parts by weight of sodium silicate (No. 1) and 5,000 parts by weight of water were added and sufficiently reacted, and smectite (synthesized by Coop Chemical Co., Ltd.) First step of mixing 5 parts by weight of fine powder of smectite) and thoroughly pulverizing and mixing, 15 parts by weight of zinc oxide powder is added to the mixed solution obtained in the first step, and further 3 parts by weight of alumina fine powder, Second step of adding 5 parts by weight of zirconia fine powder and pulverizing and mixing again, and 8 parts by weight of titanium oxide was added to the mixed solution obtained in the second step to a solution colored white, and 12 parts by weight of lithium hydroxide. The third step of adding 400 parts by weight of an aqueous solution in which is dissolved and sufficiently stirring and mixing, and the mixed solution obtained in the third step is applied to the surface of metal and ceramic to about 80 μm, and then 2
A strong coating layer was formed by drying and heating at 00 ° C. The results are shown in Table 1.

[0018]

[Table 1]

Example 2 To 100 parts by weight of fine silicon powder, 1,800 parts by weight of potassium silicate and 3,000 parts by weight of water were added and sufficiently reacted, and smectite (synthetic smectite manufactured by Corp Chemical Co., Ltd.) was added. ) The first step of mixing 3 parts by weight of the fine powder and thoroughly crushing and mixing,
8 parts by weight of zinc oxide was added to the mixed solution obtained in the first step, 3 parts by weight of alumina fine powder and 3 parts by weight of zirconia fine powder were added, and the mixture was pulverized and mixed again. In the third step of adding 6 parts by weight of titanium oxide to the obtained mixed solution and adding 100 parts by weight of an aqueous solution in which 4 parts by weight of lithium hydroxide is dissolved to the solution colored white, and stirring the mixture sufficiently. After applying the obtained mixed solution on the surface of metal and ceramic to about 80 μm,
A strong coating layer was formed by drying and heating at 00 ° C. The results are shown in Table 2.

[0020]

[Table 2]

Example 3: 300 parts by weight of potassium silicate and 1 part of potassium silicate to 100 parts by weight of fine silicon powder,
The first step in which 500 parts by weight and 4,000 parts by weight of water are added and sufficiently reacted, and 2 parts by weight of fine powder of smectite (synthetic smectite manufactured by Coop Chemical Co., Ltd.) is mixed and sufficiently pulverized and mixed. And a second step in which 10 parts by weight of zinc oxide is added to the mixed solution obtained in the first step, two kinds of alumina fine powder of 5 parts by weight and zirconia fine powder of 2 parts by weight are added, and the mixture is pulverized and mixed again. Aqueous solution 2 in which 6 parts by weight of titanium oxide was added to the mixed solution obtained in the second step and 8 parts by weight of lithium hydroxide was dissolved in a white colored solution 2
The third step of adding 00 parts by weight and sufficiently stirring and mixing, and the mixed solution obtained in the third step is applied to the surface of metal and ceramic to about 80 μm, and then dried and heated at 250 ° C. A different coating layer was formed. The results are shown in Table 3.

[0022]

[Table 3]

[0023]

As described in the above examples, the present invention has the following excellent effects. (1) Conventionally, there is no commercially available inorganic coating agent in which a coating layer is formed at a heating temperature of 500 ° C. or lower, but it is possible to form a coating layer on a substrate at 500 ° C. to room temperature, particularly 300 to 150 ° C. The reason is that the compositional formula of melting mainly by adjusting the chemical composition of the glaze of ceramics has a minimum heating temperature of up to 600 ° C.
Since the composition formula based on the temperature below 00 ° C is not shown, 600
No glaze melts below ℃. Therefore, the commonly used lead glaze is in the range of 600 ° C to 850 ° C, and the temperature at which the coating layer is stably formed on the surface of the interior / exterior material together with the borosilicate glass is about 800 ° C.
The low melting point glass for sealing electronic circuits has a minimum softening point of about 440 ° C., and this glass also has a large content of lead oxide. (2) The coating material according to the present invention is made of an inorganic material as a raw material, and therefore does not burn by heating and is heat resistant, and only moisture is generated, which is odorless and harmless. In addition, the coating layer is corrosion resistant,
Due to its excellent weather resistance and chemical resistance, as well as its stain resistance, the surface stain resistance due to oil-based magic coating can be completely wiped off by solvent washing. Further, since the coating layer film has a hardness of about 5 to 6, it has sufficient surface hardness such that it is not scratched even when scratched by a metal.

(3) When the coating layer is formed, the same coating agent can be repeatedly applied three times, and the adhesion thickness per time is about 50 to 20 μm, and the surface hardness is almost constant up to a thickness of about 100 μm. Secured in. In addition, since the base material for forming the coating layer can firmly adhere to the surface of metal, ceramic, cement / concrete, glass, natural stone and artificial stone, and it is possible to manufacture various colors from transparent to white to black. The silk screen method enables the transfer of beautiful paintings by free color processing. (4) Regarding economy, the amount of coating agent used is 6
It is around 00 g / m ² and is inexpensive at around 500 yen / kg. Therefore, it is generally cheaper than conventional organic paints. (5) Since the forming temperature of the coating layer is 300 ° C or lower, the forming temperature of the conventional glaze is 1,100 to 1,200 ° C.
It has an extremely low temperature of about / 4 and exhibits excellent physical properties. As described above, heating at a low temperature makes the equipment cost, fuel cost, operating cost, etc. for forming the coating layer extremely low, and there is no pollution by exhaust gas. It becomes possible to form a pollution-free industry that is energy-saving and labor-saving and is kind to the global environment. The application direction of the coating layer formed as described above is as a coating layer for interior and exterior surfaces for building materials, such as residential building materials, tunnel inner wall boards, guard rails and complex paralines, surface coating of oil and LPG storage tanks, and road surfaces. It can be used in various fields such as line drawing.

[Brief description of drawings]

Figure 1: X-ray diffraction pattern of smectite

FIG. 2 X-ray diffraction pattern of zinc oxide

FIG. 3 X-ray diffraction pattern of alumina

FIG. 4 X-ray diffraction pattern of zirconia

FIG. 5: X-ray diffraction pattern of titanium oxide

FIG. 6: X-ray diffraction pattern of lithium hydroxide

FIG. 7: Silicon-alkali silicate coating layer (2
X-ray diffraction diagram of heating at 00 ℃)

FIG. 8: X-ray diffraction diagram of silicon-alkali silicate-smectite coating layer (heated at 250 ° C.)

FIG. 9 is an X-ray diffraction diagram of a silicon-alkali silicate-smectite-zinc oxide-alumina-zirconia-titanium oxide coating layer.

FIG. 10: X-ray diffraction diagram of silicon-alkali silicate-smectite-zinc oxide-alumina-zirconia-titanium oxide-lithium hydroxide coating layer (250 ° C. heating)

Claims (7)

[Claims] 1. To 100 parts by weight of silicon fine powder,
4,000 to 600 parts by weight of alkali silicate and 8,000 water
The first step of adding 0 to 2,000 parts by weight and sufficiently stirring and mixing, and then adding 8 to 1 parts by weight of smectite powder thereto and sufficiently pulverizing and mixing, and the mixing obtained in the first step 30 to 3 parts by weight of zinc oxide is added to the liquid, and one or more of alumina, zirconia or silicon oxide and lithium aluminosilicate powder 1
The second step of adding 0 parts by weight or less and pulverizing and mixing again, and the mixed liquid obtained in the second step, lithium, calcium,
An aqueous solution containing 20 to 0.5% by weight of one or more water-soluble compounds of barium, strontium or cesium is used.
A third step of adding 0 to 50 parts by weight and sufficiently stirring and mixing the third step, a method for producing a low-temperature-curable inorganic coating agent. 2. With respect to 100 parts by weight of silicon fine powder,
2,000 to 1,000 parts by weight of alkali silicate and water 5,
000 to 3,000 parts by weight is added and sufficiently stirred and mixed, and 8 to 1 parts by weight of smectite powder is added thereto, and the mixture is sufficiently pulverized and mixed, and the mixture obtained in the first step 20 to 5 parts by weight of zinc oxide is added to the solution, and one or more of alumina, zirconia or silicon oxide and lithium aluminosilicate powder 5
Second step of adding ~ 1 part by weight and pulverizing and mixing again, and a small amount of titanium oxide powder in the mixed solution obtained in the second step,
After adding an inorganic pigment such as iron oxide powder for coloring, 400 to 100 parts by weight of an aqueous solution containing 15 to 1% by weight of one or more water-soluble compounds of lithium, calcium, barium, strontium or cesium is sufficiently added. A method for producing a low-temperature-curable inorganic coating agent, which comprises a third step of stirring and mixing. 3. The alkali silicate is sodium silicate and / or potassium silicate, according to claim 1 or 2.
A method for producing the low-temperature-curable inorganic coating agent as described. 4. With respect to 100 parts by weight of silicon fine powder,
4,000 to 600 parts by weight of alkali silicate and 8,000 water
The first step of adding 0 to 2,000 parts by weight and sufficiently stirring and mixing, and then adding 8 to 1 parts by weight of smectite powder thereto and sufficiently pulverizing and mixing, and the mixing obtained in the first step 30 to 3 parts by weight of zinc oxide is added to the liquid, and one or more of alumina, zirconia or silicon oxide and lithium aluminosilicate powder 1
The second step of adding 0 parts by weight or less and pulverizing and mixing again, and the mixed liquid obtained in the second step, lithium, calcium,
An aqueous solution containing 20 to 0.5% by weight of one or more water-soluble compounds of barium, strontium or cesium is used.
The third step of adding 0 to 50 parts by weight and thoroughly stirring and mixing, and the mixture obtained in the third step is applied to the surface of the substrate such as metal, ceramic, cement / concrete, stone material, glass, etc., and then at room temperature. 4. A method for forming a low temperature curing type inorganic coating layer, which comprises a fourth step of drying and heating at ˜500 ° C. 5. With respect to 100 parts by weight of silicon fine powder,
2,000 to 1,000 parts by weight of alkali silicate and water 5,
000 to 3,000 parts by weight is added and sufficiently stirred and mixed, and 8 to 1 parts by weight of smectite powder is added thereto, and the mixture is sufficiently pulverized and mixed, and the mixture obtained in the first step 20 to 5 parts by weight of zinc oxide is added to the solution, and one or more of alumina, zirconia or silicon oxide and lithium aluminosilicate powder 5
Second step of adding ~ 1 part by weight and pulverizing and mixing again, and a small amount of titanium oxide powder in the mixed solution obtained in the second step,
After adding an inorganic pigment such as iron oxide powder for coloring, 400 to 100 parts by weight of an aqueous solution containing 15 to 1% by weight of one or more water-soluble compounds of lithium, calcium, barium, strontium or cesium is sufficiently added. After the third step of stirring and mixing into a mixture and the mixed solution obtained in the third step are applied to the surface of a substrate such as metal, ceramic, cement / concrete, stone, glass, etc., drying and heating at 150 to 300 ° C A method for forming a low-temperature-curable inorganic coating layer, which comprises a fourth step. 6. The method according to claim 4, wherein the alkali silicate is sodium silicate and / or potassium silicate.
A method for forming a low temperature-curable inorganic coating layer as described above. 7. The low temperature curable inorganic coating layer according to claim 5, wherein the fine powder of iron oxide or titanium oxide is a commercially available inorganic pigment having a particle size of 0.5 μm or less. Forming method.