KR102001639B1 - inorganic binder composition - Google Patents

Abstract

The present invention relates to a high concentration inorganic binder composition having excellent water resistance, an inorganic coating agent composition having excellent adhesion and water resistance comprising the same, and an inorganic adhesive composition. The inorganic binder composition comprises: a soluble silicate having 30 to 50% of concentration and including silica and alkali metal oxide having the molar ratio of the silica to an alkali metal oxide is 1 : 2.5 to 1 : 3.5; a water-soluble alkali neutral salt which has an acid and alkali action on the soluble silicate; and an acid solution added to a mixture of the soluble silicate and the alkali neutral salt.

Description

Inorganic binder composition < RTI ID = 0.0 >

The present invention relates to a high concentration, water-resistant inorganic binder composition, and it includes application inventions such as a coating agent and an adhesive including an inorganic binder composition.

Soluble silicates are compounds in which silica (SiO ₂ ) and alkali metal oxide (M ₂ O) bind at various molar ratios and are one of the oldest and most friendly inorganic compounds. Generally, it contains some water in the structure and is expressed by the molecular formula of M ₂ O-nSiO ₂ -xH ₂ O. Soluble silicates are also referred to as water glass because they are soluble in water. Depending on the kind of alkali metal (M), it is classified into sodium silicate, potassium silicate and lithium silicate. The characteristics of the liquid silicate vary depending on the composition ratio and various molar ratios and concentrations.

Attempts have long been made to apply soluble silicates as inorganic coatings and inorganic adhesives. However, the water solubility of the soluble silicate has been limited due to the lack of water resistance of the coating and adhesion. KS M 1415, the most representative water glass of liquid sodium silicate, is classified by the sodium oxide content (Na ₂ O%) and the silica content (SiO ₂ %). The molar ratio and content of silica to alkali metal oxide were 2.18 and 53-56%, the average molar ratio was 2.49 and 48-51%, the average molar ratio was 3.15 and the content was 37-40% , And the four species have an average molar ratio of 3.81 and a content of 29-32%.

<KS M 1415 Quality standard of liquid sodium silicate (sodium silicate)> Item / Type 1 species 2 species 3 species 4 species Specific gravity (20 ℃) 1.690+ 1.590 or more 1.380 or higher 1.260 or higher Water insoluble fraction (%) 0.2 or less 0.2 or less 0.2 or less 0.2 or less Sodium oxide (Na ₂ O) (%) 17 ~ 18 14-15 9-10 6 to 7 Silicon dioxide (SiO ₂₎ (%) 36 ~ 38 34-36 28 to 30 23-25 Iron (III) oxide (Fe ₂ O ₃ ) (%) 0.05 or less 0.05 or less 0.03 or less 0.03 or less

When the molar ratio of silica to alkali metal oxide (SiO ₂ / M ₂ OX 1.032) of water glass is low, a high amount of water glass can be produced, but it is easily dissolved again in water after curing and is poor in water resistance. When the molar ratio is high, the property of being dissolved again in water after curing is lowered, and the water resistance is improved, but there is a limit to increase the content of water glass. In general, one to three kinds of water glass have the advantages of heat resistance and bonding strength as inorganic binders, but they are limited in their use for applications requiring durability because of their low water resistance. Four species are treated as high molar ratio watery glass, but the content is low and the water content is high compared with one species to three species.

Inorganic coatings (including inorganic coatings) and inorganic adhesives that are safe and excellent in performance without the generation of toxic chemicals are required as they have a high heat resistance and are required to be soluble silicates having high content and water resistance as basic inorganic binders have.

Korean Patent Publication No. 2005-0037643

Disclosure of the Invention The present invention provides a high-concentration inorganic binder having excellent water resistance.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not intended to limit the invention to the precise form disclosed. It can be understood.

The inorganic binder composition of the present invention for achieving the above object is a soluble silicate containing a silica and an alkali metal oxide having a concentration of 30 to 50% and a molar ratio of silica to alkali metal oxide of 1: 2.5 to 1: 3.5 ; Soluble alkaline neutral salts having an acid and an alkali acting on the soluble silicate; And an acid solution added to the mixture of the soluble silicate and the alkali neutral salt.

In one embodiment, the alkali metal may comprise at least one of lithium, sodium and potassium.

In another embodiment, the soluble silicate may comprise at least one of sodium silicate, potassium silicate and lithium silicate.

In another embodiment, the concentration of the soluble silicate is 35 to 45%, the water-soluble alkali neutral salt includes an alkali metal, and the alkali neutral salt relative to the alkali metal oxide contained in the soluble silicate is dissolved in water The molar ratio of alkali metal oxide to be produced may be 100: 1 to 100: 10.

In another embodiment, the alkali neutral salt is dissociated from the water into an alkali metal cation and an acid anion, and the alkali metal may include at least one of lithium, sodium or potassium.

In another embodiment the alkali neutral salt is selected from the group consisting of sodium bicarbonate, sodium chloride, sodium carbonate, sodium nitrite, sodium hypochlorite, sodium hypochlorite, sodium bicarbonate, sodium alginate, sodium citrate, sodium borate, potassium nitrate, potassium chloride, potassium sorbate, Potassium carbonate, potassium phosphate, potassium phosphate, and lithium carbonate.

In another embodiment, the acid solution dissociates in water to produce hydrogen ions, wherein the acid solution comprises a tetraacid in a monohydric acid and is selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, boric acid, acetic acid, tartaric acid, formic acid and citric acid And may include any one or more of them.

In another embodiment, the acid solution comprises a cation and an anion, and the molar ratio of the anion of the acid to the cation of the alkali metal contained in the soluble silicate may be 100: 5.5 to 100: 34.5.

In an embodiment of the another aspect of the present invention, the inorganic coating composition comprising the inorganic binder composition is such that the inorganic binder composition and water comprise 40 to 60% by weight; And 40 to 60% by weight of an inorganic pigment, and the concentration of the soluble silicate may be 35 to 40%.

In one embodiment, the weight ratio of water to the inorganic binder composition may be from 8:10 to 12:10.

In another embodiment, the inorganic pigment may include at least one of calcium carbonate, aluminum oxide, zinc oxide, zirconium oxide and oxides, per minute.

In another embodiment of the present invention, the inorganic adhesive composition comprising the inorganic binder composition comprises 60 to 80% by weight of an inorganic binder composition; And 20 to 40% by weight of aluminum silicate, and the concentration of the soluble silicate may be 40 to 45%.

As described above, the present invention has been made to solve the problems of the prior art as described above, and it is an inorganic binder composition exhibiting water resistance at a high concentration at a higher molar ratio than the soluble silicate salt, and has exceeded the limit of the commercially available soluble silicate.

Further, when the inorganic binder composition of the present invention is applied to the preparation of an inorganic coating agent (including an inorganic paint) and an inorganic adhesive agent, an excellent adhesion and water resistance are exhibited.

FIG. 1 is a photograph showing the adhesion and water resistance of a product to which the inorganic coating composition of the present invention is applied.
Fig. 2 is a photograph showing the adhesion and water resistance of a product to which the inorganic adhesive composition of the present invention is applied.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms " comprising, "" including, " or" having ", when used in this application, specify features, numbers, steps, operations, elements, But do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, preferred embodiments will be described in detail. In the following description of the present invention, the well-known functions or constructions are not described in order to simplify the gist of the present invention.

The inorganic binder composition of the present invention includes a soluble silicate, a water-soluble alkali neutral salt, and an acid solution.

The inorganic binder composition of the present invention can be used for various industrial applications. Particularly, it is preferable for a coating agent or an adhesive agent which requires excellent adhesion and water resistance.

The soluble silicate of the present invention refers to a compound in which silica and an alkali metal oxide are bound in various molar ratios.

The soluble silicate of the present invention may have a concentration of 30 to 50%. Soluble silicates are compounds in which water is contained in the structure and to which components comprising silica and alkali metal oxides are bonded, wherein the concentration of soluble silicate means the concentration of components other than water. When the concentration of the soluble silicate is less than 30%, the stability of the soluble silicate is relatively high due to the low concentration, so there is no need to treat (add) the alkali neutral salt and there may be a problem that the bonding force is insufficient when applied to the inorganic coating agent or the inorganic adhesive have. If the concentration of the soluble silicate is more than 50%, the soluble silicate itself has a very high concentration and viscosity, so that the soluble silicate may be gelated when the alkali neutral salt and the acid solution are treated, and problems may occur when the inorganic silicate is applied to the inorganic coating or the inorganic adhesive.

The soluble silicate of the present invention may have a molar ratio of silica to alkali metal oxide ranging from 1: 2.5 to 1: 3.5. If the ratio is less than 1: 2.5, the alkali metal content in the soluble silicate may be too high to realize the water resistance. If the ratio is more than 1: 3.5, the concentration of the soluble silicate may be lowered to less than 35%.

Generally, the molar ratio in the soluble silicate means the average degree of polymerization of the silica molecules. That is, the average degree of polymerization of commercially available soluble silicate which is generally adopted is very low, in the range of 2.0 to 3.2. Since the silica molecules having low polymerization degree are unstable, they try to polycondensate with the neighboring silica molecules, and the molecular weight becomes larger and gels. However, around the silica molecules of the soluble silicate, a large amount of alkali metal ions interfere with the polycondensation between the silica molecules and stabilize the soluble silicate. Silica of soluble silicate may also be present in various forms of silicate ion monomers, polysilicic acid ions and siliceous ionic micelles on colloid, and the molar ratio is merely average.

When the concentration of soluble silicate changes or is mixed with soluble silicate of different kind or different molar ratio, the form of the silica molecule of soluble silicate changes itself towards the most stable state. "When mixing two liquid silicates with different viscosities or diluting a liquid silicate in water, it is observed that the viscosity of the mixture stabilizes after a few hours and sometimes even a few days. This means that the rearrangement of the molecules, which leads to the equilibrium distribution of the oligomers, It also means that at least some of the oligomers have a fairly stable geometric shape, so that the morphological conversion, i.e. molecular rearrangement, is somewhat difficult. (Source: Colloidal Silica Fundamentals and Applications) Are standardized with optimum content and molar ratio.

The alkali metal of the soluble silicate may be any one or more of lithium, sodium and potassium, and the soluble silicate may be any one or more of sodium silicate, potassium silicate and lithium silicate containing such an alkali metal. Generally Sodium silicate has the advantage of high viscosity and excellent adhesive strength. Potassium silicate has a viscosity lower than sodium silicate at the same solid content, so it has the advantage of softness. Lithium silicate has the advantage of achieving the highest molar ratio among the three soluble silicates have. If sodium silicate alone is used to achieve high concentration of water-resistant coatings, the viscosity will be too high to form the film, and if potassium silicate alone is used to achieve the adhesive, the viscosity will be insufficient and the adhesive will become insufficient. Since lithium silicate is a high molar ratio silicate, the content is low and the viscosity is low, so that the film formation is poor by itself. Therefore, it is necessary to use a soluble silicate in consideration of the adhesion, workability, and water resistance of the inorganic binder required for the purpose of use.

The alkali neutral salt of the present invention may include an alkali metal, and the alkali metal may be any one or more of lithium, sodium and potassium, which is the same alkali metal contained in the soluble silicate, and the alkali neutral salt is sodium hydrogen carbonate, sodium chloride , Sodium carbonate, sodium nitrite, sodium percarbonate, sodium hypochlorite, sodium bicarbonate, sodium alginate, sodium citrate, sodium borate, potassium nitrate, potassium chloride, potassium sorbate, potassium carbonate, potassium phosphate and lithium carbonate . It is important to select the alkaline neutral salt and to determine the amount of alkali silicate salt used and the level of alkali metal contained therein. The impact on cost can also be considered.

The reason why the alkali neutral salt is added to the soluble silicate is to break the balance between the optimum content and the molar ratio of the soluble silicate which is commercially available in order to produce a high concentration of the inorganic binder composition while having water resistance. The addition of the alkali neutral salt to the soluble silicate prior to the addition of the acid has a higher stability than the stability of the soluble silicate and maintains the stable state of the inorganic binder composition even after the acid treatment.

In order to increase the stability of the soluble silicate, alkali such as sodium hydroxide or potassium hydroxide may be used. However, since they only increase the stability of the soluble silicate and add alkali metal ions to the soluble silicate, they are not helpful in terms of the water resistance of the soluble silicate Do not. Since the alkali neutral salt has an alkali metal cation and an acid anion at the same time, the stability can be improved without lowering the water resistance of the water glass.

The amount (input ratio) of the alkali neutral salt of the present invention may vary depending on the concentration and viscosity of the soluble silicate. When the concentration of the soluble silicate is 30 to 50%, the alkali neutral oxide The molar ratio of the alkali metal cations formed by the salt dissociation in water may be from 100: 1 to 100: 10. If the molar ratio of the alkali metal cation generated by the water-dissociation of the alkali neutral salt relative to the alkali metal oxide contained in the soluble silicate is less than 100: 1, the effect of the addition of the alkali neutral salt may not be effective. If the molar ratio exceeds 100: 10, There may be a problem to make. More preferably, the molar ratio of the alkali metal cations formed by hydrolysis of the alkali neutral salt to the alkali metal oxide contained in the soluble silicate may be 100: 2 to 100: 6. 100: 2 to 100: 6, an effect of excellent adhesion and water resistance can be achieved when an inorganic coating or an inorganic adhesive, which is an application example of the present invention, is applied.

In other words, alkali neutral salts dissociate into alkali metal cations and acid anions in water. The alkaline neutral salts dissociated in water simultaneously act as acid and alkali to the soluble silicate. The alkali metal cation acts as a stabilizer to interfere with the polycondensation of the silica molecules and the acid anion binds to the alkali metal cations around the silica molecule, allowing the silica molecule to change shape. This reaction does not end at once, but will continue until the best stability is obtained due to the characteristics of the soluble silicate. In the present invention, the alkali neutral salt is used for the stability of the soluble silicate which can enhance the acid treatment effect, so that the stability of the soluble silicate can be controlled by determining the amount of the addition and the charging conditions. In this process, the viscosity of the soluble silicate decreases, which can be assumed to be a more stable form of the silica molecule due to the action of the acid and the alkali. However, the introduction of excessive alkali neutral salts may gel the soluble silicate during long-term storage.

The present invention includes acids in addition to soluble silicates and water soluble alkali neutral salts. The acid solution dissociates in water to produce hydrogen ions, which include a tetraacid in a monovalent acid and may be any one or more of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, boric acid, acetic acid, tartaric acid, formic acid and citric acid, And the molar ratio of the anion of the acid to the cation of the alkali metal contained in the soluble silicate may be 100: 5.5 to 100: 34.5. If the molar ratio of the anion of the acid to the alkali metal contained in the soluble silicate is less than 100: 5.5, the effect of acid addition may not occur. If the molar ratio of the acid is more than 100: 34.5, Can be. More preferably, the molar ratio of the anion of the acid to the cation of the alkali metal contained in the soluble silicate may be 100: 7 to 100: 30. 100: 7 to 100: 30, an effect of excellent adhesion and water resistance can be achieved when applying the inorganic coating or inorganic adhesive, which is an application example of the present invention. It should be noted that the use of low acid or weak acid at the time of acid addition may increase the amount of acid input and lower the concentration. It is effective to use a strong acid at a high concentration to prevent the concentration of the compound from dropping by the acid addition.

The acid of the present invention binds to an alkali metal ion in the vicinity of a silica molecule to induce polycondensation between silica molecules to increase the viscosity. Some of the alkali metal ions of the acid-treated soluble silicate are adsorbed by the acid so that they can not act as alkali. Some of them are isolated in the polycondensation structure between the silica molecules and the acid-treated soluble silicate behaves like a high molar ratio soluble silicate to improve the water resistance do.

Silica gel is formed during the acid treatment of the soluble silicate and the viscosity is increased so rapidly that the concentration of the soluble silicate is higher so that the soluble silicate can not be acid treated at a high concentration. For example, if it is desired to perform an acid treatment to behave like a 3.8 molar ratio of soluble silicate similar to four kinds of liquid sodium silicate, the concentration of soluble silicate should be lowered to 30.5% or less of the concentration of four liquid sodium silicate to obtain a stable acid-treated soluble silicate .

In the present invention, an acid is added to a soluble silicate having improved stability by the addition of an alkali neutral salt, to thereby produce a high-concentration inorganic binder having excellent water resistance. It has been experimentally confirmed that a high concentration inorganic binder having excellent water resistance has a water resistance of four or more kinds of liquid sodium silicate.

The present invention can be applied to an inorganic coating material containing the inorganic binder composition described above. It should be understood that the inorganic coating agent of the present invention generally refers to forming a surface film by overlaying an object surface such as an inorganic paint.

The inorganic coating composition of the present invention comprises 40 to 60% by weight of the above-described inorganic binder composition and water; And an inorganic pigment content of 40 to 60% by weight. At this time, when the concentration of the soluble silicate is 35 to 40%, the adhesion of the coating agent and the water resistance can be optimized.

When the content of the inorganic binder composition and the water is less than 40% by weight, the pigment may come out due to an excessive amount of the pigment. When the content of the inorganic binder composition and the water is more than 60% by weight,

The weight ratio of water to the inorganic binder composition may be from 8:10 to 12:10. When the weight ratio of water and the inorganic binder composition is less than 8:10, cracking may occur when coating the inorganic material. When the weight ratio of the water and the inorganic binder composition is more than 12:10, the adhesion may be decreased.

When the content of the inorganic pigment is less than 40% by weight, the hiding power may be deteriorated when the inorganic pigment is coated, and when the content is more than 60% by weight, the pigment may have a problem.

The inorganic pigment may be at least one of calcium carbonate, aluminum oxide, zinc oxide, zirconium oxide, and an oxide containing oxides per unit area. It has been experimentally confirmed that when the inorganic pigment is applied at the same weight ratio as the water and inorganic binder composition, the adhesion strength and water resistance are both excellent.

The present invention can be applied to an inorganic adhesive containing the inorganic binder composition described above. The inorganic adhesive of the present invention preferably contains the above-described inorganic binder composition in an amount of 60 to 80% by weight; And an aluminum silicate content of 20 to 40% by weight. At this time, the adhesive strength and water resistance of the adhesive can be optimized when the concentration of the soluble silicate is 40 to 45%.

When the content of the inorganic binder composition is less than 60% by weight, the adhesive force of the inorganic adhesive agent may be lowered. When the content of the inorganic binder composition exceeds 80% by weight, the inorganic adhesive agent has a high moisture content, There may be a problem.

The inorganic coating composition and the inorganic adhesive composition of the present invention can be used as functional coatings for architectural use and industrial use free of water resistance, heat resistance, incombustibility and VOCs.

[Example 1] Effect of inorganic binder on the amount of alkali neutral salt added

The reason why the alkali neutral salt is added to the soluble silicate is to balance the optimum amount of the soluble silicate and the molar ratio before the acid treatment to maintain the stability, and it is necessary to appropriately adjust the amount of the acid silicate to increase the acid treatment effect. The addition of the appropriate alkali neutral salt causes an acid and alkali action to change the silica molecule in the soluble silicate into a more stable form, thereby securing the viscosity stability of the inorganic binder after the acid treatment.

[Table 2] below is a test for confirming an appropriate range of alkali neutral salts required for synthesis of inorganic binders having a high concentration and a high molar ratio. As the soluble silicate, Sodium Silicate of KYUNGHYUNG RESIN Co., Ltd. and potassium silicate were mixed so as to have a concentration of 40%. Sodium phosphate of Hacheon Co., Ltd. was used as alkali neutral salt, and 98% concentrated sulfuric acid was used as the acid. The mixed silicate was added to the reactor at about 1/2 of the reactor volume, stirring was started at 50 rpm, and the alkali neutral salt was added. The stirring speed was increased up to 100 rpm, stirring was continued for 1 hour, Stirring was continued for a period of time. The effects of soluble silicate and acid addition on the inorganic binder were investigated.

division Example 1 Comparative Example 1 Comparative Example 2 Soluble silicate Sodium silicate + potassium silicate
40%
3.2 Molar ratio Sodium silicate + potassium silicate
40%
3.2 Molar ratio Sodium silicate + potassium silicate
40%
3.2 Molar ratio Alkali neutral salt input mole ratio
(Alkali: alkali) 100: 4.5 100: - 100: 12 Acid input mole ratio
(Alkali: alkali) 100: 24 100: 24 100: 24 density
(%, 250 +/- 1 DEG C) 41.2 41.3 41.0 The molar ratio due to the alkali to be titrated
(Silica: alkali) 4.02 4.23 3.65 Viscosity
(cps, 20 +/- 1 DEG C) 210 1,350 185 Low temperature viscosity
(cps, refrigerator, 24 hours) 670
Liquidity O Not measurable
Liquidity X Not measurable
Liquidity X

From Table 2, it can be seen that in Example 1, a stable compound having a higher molar ratio of silica to alkali molar ratio of the soluble silicate was obtained, whereas Comparative Example 1 had almost no role of alkali neutral salt, The molar ratio was excessively high and the stability was poor. In Comparative Example 2, the stability of the composite was poor due to the excessive addition of the alkali neutral salt. That is, it is understood that the alkali neutral salt contained in the inorganic binder preferably has a molar ratio of the alkali metal oxide contained in the alkali neutral salt to the alkali metal oxide contained in the soluble silicate of 100: 1 to 100: 10.

[Example 2] Effect of inorganic binder on the amount of acid solution

When an acid is added to the soluble silicate, the acid solution binds to the alkali metal ion around the silica molecule to induce polycondensation between the silica molecules and increase the viscosity. Some of the alkali metal ions of the soluble silicate treated by the acid solution are adsorbed by the acid and do not act as alkali. Some of the soluble silicates isolated in the polycondensation structure between the silica molecules behave like high molar ratio soluble silicate, . Excessive addition of the acid solution makes the soluble silicate gelling impossible to apply to coatings and adhesives.

[Table 3] below is a test for confirming an appropriate range of the acid solution required for synthesis of a high-concentration, high-molar-ratio inorganic binder. As the soluble silicate, Sodium Silicate of KYUNGHYUNG RESIN Co., Ltd. and potassium silicate were mixed so as to have a concentration of 40%. The alkali neutral salt used was sodium phosphate of Hacheon Co., Ltd. and 85% phosphoric acid was used as the acid. The mixed silicate was added to the reactor at about 1/2 of the reactor volume, stirring was started at 50 rpm, and the alkali neutral salt was added. The stirring speed was increased up to 100 rpm, stirring was continued for 1 hour, Stirring was continued for a period of time. The effects of soluble silicate and alkali neutral salt on the inorganic binder were investigated.

division Example 2 Comparative Example 3 Comparative Example 4 Soluble silicate Sodium silicate + potassium silicate
40%
3.2 Molar ratio Sodium silicate + potassium silicate
40%
3.2 Molar ratio Sodium silicate + potassium silicate
40%
3.2 Molar ratio Alkali neutral salt input mole ratio
(Alkali: alkali) 100: 4.5 100: 4.5 100: 4.5 Acid input mole ratio
(Alkali: alkali) 100: 24 100: 5 100: 35 density
(%, 250 占 2 占 폚, 1 hour) 42.1 39.9 43.1 The molar ratio due to the alkali to be titrated
(Silica: alkali) 4.0 3.08 4.7 Viscosity
(cps, 20 +/- 1 DEG C) 200 170 1,500 or more Low temperature viscosity
(cps, refrigerator, 24 hours) 650
Liquidity O 390
Liquidity O Not measurable
Liquidity X

Table 3 shows that in Example 2, a stable compound having a higher molar ratio of silica to alkali molar ratio of soluble silicate was obtained. In Comparative Example 3, the role of acid was little, so that the molar ratio of the compound to the soluble silicate And the water resistance was not improved. In Comparative Example 4, the stability of the composite was poor due to excessive addition of acid. That is, the acid solution contained in the inorganic binder is found to have a molar ratio of the anions in the acid solution to the alkali metal cations contained in the soluble silicate of 100: 5.5 to 100: 34.5.

[Example 3] Effect of inorganic binder on the concentration of soluble silicate

This inorganic binder is aimed at a high concentration of a water-resistant inorganic binder. In order to synthesize an inorganic binder having a concentration of 35% or more, the concentration of the soluble silicate needs to be 35 to 45%. When the concentration of the soluble silicate is less than 35%, it is more advantageous to increase the water resistance of the inorganic binder, so that it can be used as a transparent coating agent for a thin film, but it is not preferable for an inorganic coating composition or an inorganic adhesive composition. When the concentration of the soluble silicate is more than 45%, the soluble silicate has a large amount of alkali metal cations, so that the effect of improving the water resistance can not be expected by adding the alkali neutral salt and the acid solution. A high concentration of soluble silicate means that the molar ratio is low (containing more alkali metal cations) and good adhesion. The concentration of soluble silicate in the inorganic binder determines the application (application) of the inorganic binder.

Table 4 below is a test for confirming the effect of the concentration of the inorganic binder or the soluble silicate on the inorganic coating composition. For the synthesis of Example 3, sodium silicate of Yongil Chemical Co., Ltd. and potassium silicate were mixed as a soluble silicate to a concentration of 39%. The alkali neutral salt was sodium phosphate of Hacheon Co., Ltd., and the acid solution was 35% hydrochloric acid. The mixed silicate was added to the reactor at about 1/2 of the reactor volume, stirring was started at 50 rpm, and the alkali neutral salt was added. The stirring speed was increased up to 100 rpm, stirring was continued for 1 hour, Stirring was continued for a period of time. Four kinds of sodium silicate were compared and evaluated in Comparative Example 5 as a low-concentration, high-molar-ratio inorganic binder together with Example 3.

division Example 3 Comparative Example 5 Soluble silicate Sodium silicate + potassium silicate
39% 4 kinds of sodium silicate Alkali neutral salt input mole ratio
(Alkali: alkali) 100: 5 - Acid input mole ratio
(Alkali: alkali) 100: 25 - pH 11.6 11.9 Specific gravity (20 ± 1 ℃) 1.402 1.292 Viscosity
(cps, 20 +/- 1 DEG C) 350 75 density
(%, 250 占 2 占 폚, 1 hour) 40.3 31.0

[Example 4]

The inorganic coating composition of the following Table 5 was tested by using 25% by weight of an inorganic binder, 25% by weight of water, 25% by weight of calcium and 25% by weight of calcium carbonate.

division The inorganic coating composition of Example 3 The inorganic coating composition of Comparative Example 5 water 25 25 Inorganic binder 25 25 Pigment Party 25 25 Calcium carbonate 25 25 system 100 100 Attachment * Good Bad Water resistance ** Good Bad

Adhesiveness *: Crosscut, Appearance

Water resistance **: Check the film for abnormality after holding for 24 hours under 80% humidity and 80 ± 1 ℃

The inorganic coating composition to which Example 3 was applied exhibited good adhesion, spreadability and water resistance, while the inorganic coating composition to which Comparative Example 5 was applied showed poor adhesion, wettability and water resistance It was judged to be unsuitable as an inorganic coating agent.

From the above results, it can be seen that the concentration of the inorganic binder influences the adhesion and the water resistance of the inorganic coating agent even in the case of a high-molar ratio inorganic binder. For good performance of the inorganic coating composition, the concentration of soluble silicate should be 35-40%.

[Example 5]

Table 6 below is a test for confirming the influence of the concentration of the inorganic binder or soluble silicate on the inorganic adhesive composition. For the synthesis of Example 4, sodium silicate of Yongil Chemical Co., Ltd. and potassium silicate as a soluble silicate were mixed so as to have a concentration of 44%. The alkali neutral salt was sodium phosphate of Hacheon Co., Ltd., and the acid solution was 35% hydrochloric acid. The mixed silicate was added to the reactor at about 1/2 of the reactor volume, stirring was started at 50 rpm, and the alkali neutral salt was added. The stirring speed was increased up to 100 rpm, stirring was continued for 1 hour, Stirring was continued for a period of time. Sodium silicate 2-1 of Young Il Chemical Co., Ltd. was used in Comparative Example 6 as a high-concentration inorganic binder together with Example 4.

division Example 4 Comparative Example 6 Soluble silicate Sodium silicate + potassium silicate
44% Sodium silicate 2-1 (Young Il Hwaseong) Alkali neutral salt input mole ratio
(Alkali: alkali) 100: 5.5 - Acid input mole ratio
(Alkali: alkali) 100: 15 - pH 12.4 12.8 Specific gravity (20 ± 1 ℃) 1.510 1.554 Viscosity
(cps, 20 +/- 1 DEG C) 650 1,020 density
(%, 250 占 2 占 폚, 1 hour) 45.7 47.1

[Example 6]

The inorganic adhesive composition of the following [Table 7] was tested with 70% by weight of an inorganic binder and 30% by weight of aluminum silicate.

division The inorganic adhesive composition of Example 4 The inorganic adhesive composition of Comparative Example 6 Inorganic binder 70 70 Aluminum silicate 30 30 system 100 100 Adhesion * (N / cm ² ) Good Good Water resistance ** (N / cm ² ) Good Can not be measured by sticking off

Adhesion *: Compressive shear strength according to KS M 3705 (state), Wood specimen, 3 day adhesive strength

Water resistance **: Compressive shear strength according to KS M 3705 (domestic water), Wood specimen, 1 day after immersion

The inorganic adhesive composition to which Example 4 was applied exhibited good adhesion and water resistance, whereas the inorganic adhesive coating composition to which Comparative Example 6 was applied showed good adhesion but poor water resistance, .

From the above results, it can be seen that the concentration of the inorganic binder influences the adhesive force and the water resistance of the inorganic adhesive. For the purpose of exhibiting good performance of the inorganic adhesive composition, the concentration of soluble silicate is preferably 40 to 45%.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

Claims (12)

A composition containing water in the structure and comprising components comprising silica and an alkali metal oxide, wherein the concentration of components other than water is 35 to 45%, and the molar ratio of silica to alkali metal oxide is 1 : 2.5 to 1: 3.5;
A water-soluble alkali neutral salt which is added to the soluble silicate and contains at least one of lithium, sodium or potassium as an alkali and acts as an alkali with the soluble silicate; And
An acidic solution added to the mixture of the soluble silicate and the alkali neutral salt; and an inorganic binder composition
The method according to claim 1,
Wherein the alkali metal comprises at least one of lithium, sodium, and potassium.
The method of claim 2,
Wherein the soluble silicate includes at least one of sodium silicate, potassium silicate and lithium silicate.
The method according to claim 1,
The alkali neutral salt is dissociated from water into alkali metal cations and acid anions,
Wherein the molar ratio of the alkali metal cations formed by hydrolysis of the alkali neutral salt with respect to the alkali metal oxide contained in the soluble silicate is 100: 1 to 100: 10
delete The method according to claim 1,
Wherein the alkali neutral salt is selected from the group consisting of sodium bicarbonate, sodium chloride, sodium carbonate, sodium nitrite, sodium hypochlorite, sodium bicarbonate, sodium alginate, sodium citrate, sodium borate, potassium nitrate, potassium chloride, potassium sorbate, potassium carbonate, An inorganic binder composition comprising at least one of lithium carbonate and lithium carbonate
The method according to claim 1,
The acid solution dissociates in water to generate hydrogen ions. The acid solution includes at least one of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, boric acid, acetic acid, tartaric acid, formic acid and citric acid Characterized by an inorganic binder composition
The method according to claim 1,
Wherein the acid solution comprises a cation and an anion,
Wherein the molar ratio of the anion of the acid to the cation of the alkali metal contained in the soluble silicate is 100: 5.5 to 100: 34.5.
The inorganic binder composition according to any one of claims 1 to 4 and 6 to 8 and water comprise 40 to 60% by weight; And
40 to 60% by weight of an inorganic pigment,
The concentration of the soluble silicate components other than water is 35 to 40%
Wherein the weight ratio of the water to the inorganic binder composition is from 8:10 to 12:10.
delete The method of claim 9,
Wherein the inorganic pigment comprises at least one of calcium carbonate, aluminum oxide, zinc oxide, zirconium oxide, and an oxide including at least one oxide per molecule.
60 to 80% by weight of an inorganic binder composition according to any one of claims 1 to 4 and 6 to 8; And
From 20 to 40% by weight of aluminum silicate,
Wherein the concentration of the components of the soluble silicate other than water is 40 to 45%.

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