KR102136287B1 - Eco-friendly anti-rust composition and method for manufacturing the same - Google Patents

Abstract

The present invention relates to an eco-friendly anti-rust agent and a preparation method of the same. The present invention provides an eco-friendly anti-rust agent comprising: tannic acid (C_(76)H_(52)O_(46)); a silane polymer; an organic solvent; and water. In addition, the present invention provides a preparation method of an eco-friendly anti-rust agent, comprising: a first step of obtaining solution A in which tannic acid (C_(76)H_(52)O_(46)) is dissolved; a second step of obtaining solution B comprising a polysiloxane complex in which nanosilica sol (nano SiO_2 sol) and silicate are polycondensed; and a third step of mixing the solution A with the solution B. According to the present invention, the eco-friendly anti-rust agent is harmless to a human body and eco-friendly, has excellent anti-rust performance along with corrosion resistance, and has the function of a paint.

Description

ECO-FRIENDLY ANTI-RUST COMPOSITION AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to an eco-friendly rust inhibitor and a method for manufacturing the same, while effectively preventing rust from being formed on the surface of the metal, and having the function of preventing corrosion of the metal and painting, and being harmless to the human body and eco-friendly. It relates to an anti-rust agent and a method of manufacturing the same.

In general, almost all surfaces exposed in the air are oxidized by oxygen or moisture, and rust or corrosion occurs. Rust and corrosion occur not only in metal structures such as iron and non-ferrous systems, but also in non-metal structures such as concrete walls, which degrades the physical properties and appearance of the structure. In particular, the strength, conductivity and durability (life) of the molten metal are reduced.

As a method for preventing rust of the metal, it can be roughly divided into an electric method and a film-type method. The electric method is a method of delaying corrosion by installing the sacrificial anode on the steel structure so that the sacrificial anode is corroded faster than the steel structure. However, the electric method has a disadvantage in that a continuous effect can be seen only when a large number of sacrificial anodes are used, and it can be limitedly applied to steel structures. In addition, the electric method is uneconomical due to the high initial installation cost, maintenance cost, and electricity cost. Therefore, the film-type method is mainly used.

The coating method is a method of forming a coating by coating a surface of a metal with a rust-preventing agent (or anti-corrosive coating composition). In general, the film-type rust inhibitor includes heavy metals such as lead (Pb) or chromium (Cr), such as red lead, zinc chromate, lead cyanide, and strontium chromate. Has been used. However, it contains heavy metals such as lead (Pb) and chromium (Cr), which is harmful to the human body and causes environmental pollution, and its future use may be prohibited.

Accordingly, recently, rust inhibitors that do not contain heavy metals such as lead (Pb) or chromium (Cr) have been proposed. For example, Korean Patent Publication No. 10-1039307 discloses an rust inhibitor composition in which an alkali metal and aluminum powder are mixed with an epoxy resin or an acrylic resin, and Korean Patent Publication No. 10-1359942 uses a water-soluble acrylic emulsion. A method for producing the aqueous rust inhibitor composition used is presented. In addition, in Korean Patent Publication No. 10-2011-0036473 and Korean Patent Registration No. 10-1950495, antirust coatings using inorganic acids such as nitric acid, hydrochloric acid, and phosphoric acid are proposed.

However, the rust inhibitor according to the prior art (rust inhibitor composition) has the following problems, for example. First, the rust-preventing agent having an epoxy-based resin or an acrylic-based resin as a main component has low rust-preventing ability. In addition, rust inhibitors using inorganic acids (nitric acid, hydrochloric acid, phosphoric acid, etc.) are irritating or difficult to handle, and may etch (cut off) metal products or cause corrosion to shorten the life of the product.

Above all, the rust inhibitor according to the prior art has a problem of poor persistence and storage stability. Specifically, the rust-preventing agent according to the prior art is coated with a metal, and after a certain period of time, the rust-preventing ability is lowered and the permanent persistence is poor. In addition, there is a problem that layer separation or precipitation occurs during long-term storage.

Korean Registered Patent Publication No. 10-1039307 Korean Registered Patent Publication No. 10-1359942 Korean Patent Publication No. 10-2011-0036473 Korean Registered Patent Publication No. 10-1950495

Accordingly, the present invention has an object to provide an improved eco-friendly rust inhibitor and a method for manufacturing the same.

Specifically, the present invention is an eco-friendly rust-preventing agent that is harmless to the human body and environmentally friendly, has excellent rust-preventing properties, as well as improved durability and storage stability, while having the function of rust-preventing and corrosion-resistant metals and paints. The object is to provide a method of manufacturing the same.

The present invention to achieve the above object,

Tannic acid (C ₇₆ H ₅₂ O ₄₆ );

Silane polymers;

Organic solvents; And

It provides an eco-friendly rust inhibitor containing water.

According to one embodiment, the silane polymer may include a polysiloxane complex compound of a nano silica sol (nano SiO ₂ sol) and a silicate (silicate).

In addition, the present invention,

A first step of obtaining A solution in which tannic acid (C ₇₆ H ₅₂ O ₄₆ ) is dissolved;

A second step of obtaining a liquid B comprising a polysiloxane complex compound of a nano-silica sol (nano SiO ₂ sol) and a silicate (polysilicate); And

It provides a method of manufacturing an environmentally friendly rust inhibitor comprising a third step of mixing the A solution and B solution.

According to one embodiment, the first step of obtaining the A solution is (a) primary dissolution of 20 to 40% by weight of tannic acid and 20 to 40% by weight of an organic solvent at 20°C to 30°C with stirring and mixing. Step and (b) may include a second dissolution step of adding and stirring and mixing at a temperature of 35°C to 40°C with 20 to 50% by weight of water added to the melt that has undergone the first dissolution step.

In addition, the second step of obtaining the B solution, (1) nano-silica sol (nano SiO ₂ sol) 20 ~ 30% by weight of the organic solvent and 20 ~ 30% by weight of water and mixing 20 ~ 30% by weight of water 60 ℃ ~ It may include a reaction step of reacting at a temperature of 80 ℃, and (2) polycondensation step of polycondensing at a temperature of 60 ℃ to 80 ℃ by putting the silicate (silicate) 20 to 30% by weight while proceeding the reaction.

In addition, in the third step of mixing the A solution and the B solution, the A solution: B solution may be mixed at a weight ratio of 1:3 to 5.

According to the present invention, an eco-friendly rust inhibitor having improved properties and a method of manufacturing the same are provided.

According to the present invention, it is harmless and eco-friendly to the human body, and has a function of preventing corrosion and coating of metal with rust prevention ability. In addition, it has an excellent anti-rust ability, as well as an effect of improving durability and storage stability.

The term "and/or" used in the present invention is used to mean including at least one or more of the components listed before and after. As used herein, the term "one or more" means one or more than two.

The present invention provides an environment-friendly rust inhibitor according to the first aspect. In addition, according to the second aspect, the present invention provides a method for manufacturing a rust inhibitor, which can have excellent properties as a preferable method for producing the rust inhibitor.

The rust-preventing agent according to the present invention is used as a method of coating on an object, which at least prevents the formation of rust by forming a coating film on the object. The rust inhibitor according to the present invention may be coated by a method such as spray coating, roll coating, and brush coating when coated on an object to be coated, and the coating method is not particularly limited.

In the present invention, "anti-rust" may include the meaning of preventing (preventing) rust from being formed on the surface of the object, as well as removing rust formed on the surface of the object. In addition, in the present invention, the "coated body" may include a metal material such as an iron-based or non-ferrous-based material, and a concrete material, wood, and/or a ceramic material in addition to the metal material.

Anti-rust agents according to the present invention include tannic acid (C ₇₆ H ₅₂ O ₄₆ ) (tannic acid), silane polymer, organic solvent and water. At this time, the tannic acid (C ₇₆ H ₅₂ O ₄₆ ) acts as an active ingredient for preventing rust, and the silane polymer acts as a film forming agent.

The anti-rust agent according to the present invention includes the above components, and at least as a function of anti-rust, anti-corrosion and paint, has three or more of these functions. The rust inhibitor according to the present invention is an anti-corrosive coating composition having three or more functions as described above, which has a predetermined viscosity, for example, may have a viscosity of paint applied to a wall surface of a building. The rust inhibitor according to the present invention may have a viscosity of 1.5 to 30 poise, for example, when measured with a viscometer at room temperature (about 20°C).

In general, when metals such as iron are oxidized, iron oxides of FeO, Fe ₂ O ₃ ,·nH ₂ O, and Fe ₃ O ₄ are formed on the surface. At this time, FeO and Fe ₂ O ₃ ,·nH ₂ O form rust among the iron oxides, which have a red color. And the Fe ₃ O ₄ is black, which forms a passivation film on the metal surface to prevent corrosion and prolong the life.

The tannic acid (C ₇₆ H ₅₂ O ₄₆ ) is an aromatic having a hydroxyl group (-OH), which is oxidized upon contact with air and reacts with a metal salt to form a complex. The present invention prevents rust by using the reactivity of tannic acid to form a complex as above. Specifically, the use of OH groups of tannic acid prevents the formation of FeO and Fe ₂ O ₃ ,·nH ₂ O, which form rust upon oxidation of metal (iron), and forms a complex of Fe ₃ O ₄ and Fe ₃ O ₄ To prevent rust. That is, according to the present invention, tannic acid prevents the formation of rust (FeO and Fe ₂ O ₃ ,·nH ₂ O) upon oxidation of metal (iron), and further forms rust by forming a Fe ₃ O ₄ and a complex compound thereof Prevent it. In addition, the amount of Fe ₃ O ₄ forming a passivation film on the metal surface is increased to prevent corrosion and prolong life.

The silane polymer is one having at least one siloxane (-Si-O-) bond in the molecule, which may include, for example, a silane compound and an olefin-based (ethylene, etc.) copolymer, polysiloxane and/or polysiloxane complex, and the like. have. The silane polymer preferably contains a polysiloxane complex compound.

The polysiloxane complex compound is a polysiloxane metal salt having at least one siloxane (-Si-O-) bond in the molecule and at least one metal, which is a polycondensation of nano-silica sol (nano SiO ₂ sol) and silicate (silicate) ). The polysiloxane complex compound may have a structure in which one or more metal elements selected from sodium (Na), calcium (Ca), magnesium (Mg), and aluminum (Al) are bonded to the polysiloxane.

The polysiloxane complex compound acts as a film-forming agent forming a film (coating protective layer), which also protects tannic acid (C ₇₆ H ₅₂ O ₄₆ ) so that the rust-preventing ability is maintained continuously. In addition, the polysiloxane complex compound has excellent heat resistance and the like by forming a ceramic complex compound after coating and drying the object. Accordingly, the rust inhibitor according to the present invention has the function of a paint by the polysiloxane complex, while improving the durability and heat resistance of the rust inhibitor.

The organic solvent acts as a viscosity modifier for dissolving, dispersing, and/or coating tannic acid and a silane polymer (polysiloxane complex), which may be selected from, for example, alcohol-based and/or ketone-based. The organic solvent, for example, may be selected from ethyl alcohol and isopropyl alcohol (IPA). In addition, water is added for the same purpose as the organic solvent, which may be selected from purified water and/or distilled water.

The rust inhibitor according to the present invention is an aqueous coating type using tannic acid and a silane polymer (polysiloxane complex compound, etc.) as an active ingredient, as described above, as well as heavy metals such as lead (Pb) or chromium (Cr), as well as nitric acid or hydrochloric acid. Contains no inorganic acids. Accordingly, it is harmless to the human body and environmentally friendly. In addition, it has a function of preventing rust and corrosion by the tannic acid, and at the same time, while having at least a function of a paint by the polysiloxane complex compound, durability and heat resistance are improved.

In addition, the rust inhibitor according to the present invention is an adhesive material for improving the adhesion to the object; A heating material for heating; Strength-reinforcing material for improving surface strength; A heat-resistant material for improving heat resistance; And one or more additional components selected from additives and the like. Examples of the additives include antioxidants, sunscreens, leveling agents and/or color pigments. These additional components may be added as necessary in consideration of the application field and use of the rust inhibitor.

On the other hand, the manufacturing method of the rust inhibitor according to the present invention, the first step of obtaining a solution of A tannic acid is dissolved; A second step of obtaining a liquid B comprising a polysiloxane complex compound of a nano-silica sol (nano SiO ₂ sol) and a silicate (polysilicate); And a third step of mixing the A solution and the B solution. Hereinafter, specific embodiments will be described for each step. The manufacturing method of the present invention described below improves at least the properties of the rust inhibitor. This prevents oxidation of tannic acid and improves solubility, and thus has excellent anti-rust and storage stability. In addition, it is possible to increase the coating function and utilization of the anti-rust agent.

[1] Liquid A (Stage 1)

A solution obtained by dissolving tannic acid (C ₇₆ H ₅₂ O ₄₆ ) in an organic solvent and water is obtained. Liquid A is an aqueous solution, and is obtained by mixing 20 to 40% by weight of tannic acid, 20 to 40% by weight of organic solvent, and 20 to 50% by weight of water based on the total weight of Liquid A. In this case, the organic solvent may be selected from alcohol-based and/or ketone-based, and according to one embodiment, it is preferable to use isopropyl alcohol (IPA) or the like which is advantageous for dissolving tannic acid.

According to a preferred embodiment, the first step of obtaining the solution A is (a) a primary dissolution step of stirring and mixing 20-40% by weight of tannic acid and 20-40% by weight of an organic solvent at a temperature of 20°C to 30°C. Wow, (b) it is preferable to include a second dissolution step in which 20 to 50% by weight of water is added to the lysate that has undergone the first dissolution step and stirred and mixed at a temperature of 35°C to 40°C. At this time, the primary dissolving step may proceed for 2 minutes to 3 hours, and the secondary dissolving step may proceed for 1 minute to 2 hours, but is not limited thereto.

According to the present invention, in the preparation of the solution A (dissolution of tannic acid), the first step (a) to dissolve in an organic solvent as described above (primary dissolution), and then (b) step to dissolve by adding water (secondary Dissolution), but when proceeding at an appropriate temperature, it was found that oxidation of tannic acid is prevented and solubility is improved to have excellent anti-rust performance and storage stability.

Specifically, in preparing A solution in which tannic acid is dissolved, a method of mixing both tannic acid, an organic solvent, and water may be considered, but in this case, tannic acid is oxidized to lower the production rate of Fe ₃ O ₄ and its complex. Accordingly, the ability to inhibit the formation of FeO and Fe ₂ O ₃ ,·nH ₂ O forming rust is poor, and thus it is difficult to exhibit excellent rust prevention performance. Along with this, the solubility of tannic acid is low, so it is difficult to have good miscibility with the polysiloxane complex, and layer separation or precipitation may occur during long-term storage.

In addition, the same is the case when the mixing order of the organic solvent and water is different. That is, in preparing the solution A, for example, it is possible to consider a method in which water is first mixed and dissolved in tannic acid, and then mixed with an organic solvent. Can be.

Thus, according to a preferred embodiment of the present invention, as described above, through the steps (a) (first dissolution) and (b) (second dissolution), the tannic acid is first placed in a container solvent and the temperature is 20° C. to 30° C. After mixing and primary dissolving in, after adding water and mixing and dissolving (reacting) at a temperature of 35°C to 40°C, oxidation of tannic acid is prevented, solubility, etc. are improved to provide excellent anti-rust performance and storage stability. I can have it. In addition, in the present invention, the content of tannic acid, organic solvent, and water (% by weight) is a consideration of solubility of tannic acid and miscibility with a polysiloxane complex. That is, it is difficult to show good solubility and miscibility in which the content (wt%) of the tannic acid, organic solvent, and water is outside the above range.

[2] Liquid B (Phase 2)

In the second step advances the condensation reaction to obtain a B solution through such polycondensation reaction include a nano-silica sol (nano SiO ₂ sol) and silicate (silicate) is the polycondensation of polysiloxane complex. Liquid B contains a polysiloxane complex compound, an organic solvent, and water, which includes a polysiloxane complex compound in a gel state, for example, by a sol-gel.

According to a preferred embodiment, the second step of obtaining the B solution, (1) nano silica sol (nano SiO ₂ sol) 20 to 30% by weight of the organic solvent and 20 to 30% by weight of water and 20 to 30% by weight of water mixed And a reaction step of reacting at a temperature of 60°C to 80°C, and (2) a polycondensation step of polycondensing at a temperature of 60°C to 80°C by adding 20 to 30% by weight of silicate while performing the reaction. do. The polycondensation reaction may be performed, for example, for 20 minutes to 2 hours. At this time, in the process of obtaining the B solution, the content (% by weight) of each component is based on the total weight of the B solution.

Through the polycondensation reaction, a liquid B containing a polysiloxane complex compound in a gel state is obtained, which improves the coating function of the rust inhibitor as described above, and also improves the persistence of the rust inhibitor. In addition, after being coated on the object to be coated or dried by normal temperature or thermally dried, the polysiloxane complex compound is ceramicized to improve the strength and heat resistance of the film.

The nano-silica sol (nano SiO ₂ sol) is a sol (sol) in which nanometer (nm)-sized silica (SiO ₂ ) is dispersed, which may be a commercially available product. For the nano-silica sol (nano SiO ₂ sol), for example, SiO ₂ fine particles having a size of 1 to 100 nm may be dispersed in a solvent together with a polysiloxane or polysiloxane monomer. Further, the organic solvent may be selected from alcohol-based and/or ketone-based, and it is preferable to use, for example, isopropyl alcohol (IPA).

The silicate may include, for example, one or more selected from sodium silicate, calcium silicate, magnesium silicate, magnesium-aluminum silicate, and the like. . Further, the silicate may use a sol dispersed in a solvent.

The polysiloxane complex compound produced through the polycondensation is a gel having a structure in which one or more metal atoms selected from sodium (Na), calcium (Ca), magnesium (Mg) and aluminum (Al) are coordinated according to the type of silicate as described above. (gel) may be a polysiloxane metal salt. The polysiloxane complex compound is ceramicized after being coated/dried on the object as described above to improve the properties of the film. Accordingly, according to the present invention, sol (sol) -> gel (gel) -> ceramic (ceramic) to implement the heat resistance, weather resistance, corrosion resistance and chemical resistance, and the like.

[3] mixing

Next, the A liquid and the B liquid are mixed. (Step 3) At this time, it is preferable to mix the A liquid: B liquid in a weight ratio of 1:3 to 5. The anti-rust ability and paint function can be improved at the mixing ratio. Specifically, when the B liquid is less than 3 weight ratio outside the mixing ratio, the coating function such as coating properties may be insignificant. In addition, when the liquid B exceeds 5 weight ratio, the content of the liquid A (tannic acid) is relatively low, so that the rust-preventing ability may be insignificant.

In addition, according to another embodiment, a method of manufacturing a rust inhibitor according to the present invention includes an adhesive material for improving adhesion to an object; A heating material for heating; Strength-reinforcing material for improving surface strength; A heat-resistant material for improving heat resistance; And it may further include the step of mixing one or more additional components selected from additives and the like.

The adhesive material may be selected from polymers such as acrylic and/or epoxy, but preferably, hydroxy propyl cellulose (HPC) is used. The hydroxy propyl cellulose (HPC) is advantageous for adhesion to the object, which is also preferred for the present invention because of its excellent miscibility with the tannic acid and polysiloxane complex compounds. Thus, the method for preparing a rust inhibitor according to the present invention may further include the step of mixing hydroxy propyl cellulose (HPC).

The hydroxy propyl cellulose (HPC) may be mixed in the manufacturing process of liquid A (first step) or mixed in the manufacturing process of liquid B (second step). According to another embodiment, the hydroxy propyl cellulose (HPC) may be mixed in the mixing process of the A solution and B solution (the third step). The hydroxy propyl cellulose (HPC), for example, when mixed in the A or B solution, may be mixed in 0.5 to 5% by weight based on the total weight of the A or B solution.

The heating material may be selected from silicon carbide and/or metal oxides (such as ZnO). The heating material may be preferably one or more selected from gray silicon carbide (SiC) and green silicon carbide (SiGC). Such a heating material may be mixed in the manufacturing process of the A liquid (first step), the manufacturing process of the B liquid (the second step), or the mixing process of the A liquid and the B liquid (the third step). Such a heating material, for example, when mixed in the A or B solution, may be mixed in 0.2 to 5% by weight based on the total weight of the A or B solution.

The strength-reinforcing material may be selected from metal oxides and the like, for example, zinc oxide (ZnO), magnesium oxide (MgO), and/or aluminum oxide (Al ₂ O ₃ ). Even in the case of such a strength reinforcing material, it may be mixed in the manufacturing process of the A liquid (first step), the manufacturing process of the B liquid (the second step), or the mixing process of the A liquid and the B liquid (the third step). Further, the strength reinforcing material such as zinc oxide (ZnO) may be added after being mixed with a solvent such as normal hexane. Such a strength reinforcing material, for example, when mixed in A or B liquid, may be mixed in an amount of 0.2 to 5% by weight based on the total weight of A or B liquid.

The heat-resistant material and additives can be used that are commonly used in the art, which may be added in an amount of 0.001 to 5% by weight based on the total weight of the rust inhibitor, if necessary.

The rust inhibitor according to the present invention described above is used as a method of coating on the surface of an object such as iron-based, and after coating, it is naturally dried or thermally dried to form a rust preventive film. The rust inhibitor according to the present invention is harmless to the human body and environmentally friendly. In addition, as described above, it has the functions of rust prevention, corrosion prevention and paint, and excellent rust prevention performance and durability and storage stability are improved.

Hereinafter, examples and comparative examples of the present invention will be illustrated. The following examples and comparative examples show experimental examples for checking the rust-preventing ability and storage stability according to the preparation of solution A (dissolution of tannic acid). In addition, the following comparative example does not mean the prior art, which is provided only for comparison with the examples.

[Example 1]

In a reactor equipped with a stirrer, 30 parts by weight (g) of tannic acid (C ₇₆ H ₅₂ O ₄₆ ) and 30 parts by weight (g) of isopropyl alcohol (IPA) were added and sufficiently mixed at about 21°C for 2 minutes. Next, after the temperature of the reactor was raised to about 37° C., 40 parts by weight of purified water (g) was added and sufficiently mixed for 2 minutes at a temperature of about 37° C. to obtain a solution A (tannic acid solution).

Liquid B was prepared by mixing organopolysiloxane and hydroxy propyl cellulose (HPC) in an aqueous solution of isopropyl alcohol (IPA). Then, the obtained A liquid and B liquid were mixed in a weight ratio of 1: 3 to prepare a rust-preventing liquid according to this example.

[Comparative Example 1]

Compared to Example 1, the mixing method of the tannic acid solution was changed. Specifically, 30 parts by weight (g) of tannic acid (C ₇₆ H ₅₂ O ₄₆ ), 30 parts by weight (g) of isopropyl alcohol (IPA) and 40 parts by weight of purified water (g) in a reactor equipped with a stirrer is about 21°C. In 5 minutes, the mixture was sufficiently mixed to obtain a solution A (a solution of tannic acid). Then, Liquid B was prepared in the same manner as in Example 1, and mixed with the obtained Liquid A to prepare a rust-preventing liquid according to Comparative Example 1.

[Comparative Example 2]

Compared to Example 1, the mixing order of isopropyl alcohol (IPA) and purified water was different. Specifically, 30 parts by weight (g) of tannic acid (C ₇₆ H ₅₂ O ₄₆ ) and 40 parts by weight of purified water (g) were added to a reactor with a stirrer and sufficiently mixed for 2 minutes at about 21°C. Next, 30 parts by weight (g) of isopropyl alcohol (IPA) was added and sufficiently mixed at a temperature of about 21° C. for 2 minutes to obtain a solution A (a solution of tannic acid). Then, Liquid B was prepared in the same manner as in Example 1, and mixed with the obtained Liquid A to prepare a rust inhibitor according to Comparative Example 2.

For the rust-preventing solutions according to the Examples and Comparative Examples prepared as above, the rust-preventing ability and storage stability were evaluated as follows, and the results are shown in Table 1 below.

<Anti-rust ability>

A rusted iron plate was prepared, and a rust-preventing solution according to each example and comparative example was thinly spray-coated on the surface of the rusty iron plate. In addition, each coated specimen was left for a long period of time under high-temperature/high-humidity (temperature 45°C/humidity 80%) and sufficient air (oxygen) rust formation conditions. Thereafter, the surface of the iron plate was visually observed to confirm whether rust was formed.

In the specimen of Example 1, black was observed, and in Comparative Examples 1 and 2, red was observed. At this time, Example 1 of black means that rust was suppressed as Fe ₃ O ₄ (black), and Comparative Examples 1 and 2 of red mean that rust was generated as red rust (FeO and Fe ₂ O ₃ ㆍnH ₂ O).

<Storage stability>

The rust-preventing solutions according to the respective examples and comparative examples were put in a transparent container, and then each container specimen was placed in a constant-temperature and constant-humidity bath and stored for 5 days under high temperature/high humidity conditions at a temperature of 80°C and a humidity of 60%. At this time, the container was opened without closing the lid to expose the air. And through visual observation, it was confirmed whether color change, precipitation, and layer separation occurred. The results are shown in Table 1 below.

<Results of evaluating the properties of rust-preventing solutions according to each Example and Comparative Example> Remark Example 1 Comparative Example 1 Comparative Example 2 Mixing of A liquid
(When tannic acid is dissolved) After mixing tannic acid + IPA, mixed with purified water Mix at once After mixing tannic acid + purified water, adding IPA Anti-rust ability
(Steel plate surface) black
(Fe ₃ O ₄ ) Red
(FeO, Fe ₂ O ₃ ㆍnH ₂ O) Red
(FeO, Fe ₂ O ₃ ㆍnH ₂ O) Storage stability Color change none Browning (oxidation) Browning (oxidation) Sedimentation/layer separation none Sedimentation and layer separation Layer separation occurs

As shown in [Table 1], in preparing the A solution (tannic acid solution), when mixed according to Example 1, it was found that the rust prevention performance and storage stability are better than Comparative Examples 1 and 2 Could. This means that when mixed according to Example 1, oxidation of tannic acid is prevented and solubility is improved.

Claims (6)

delete delete delete A first step of obtaining A solution in which tannic acid is dissolved;
A second step of obtaining a liquid B comprising a polysiloxane complex compound of a nano-silica sol (nano SiO ₂ sol) and a silicate (polysilicate); And
A third step of mixing the A solution and B solution,
The first step of obtaining the liquid A,
(a) a primary dissolution step of stirring and mixing 20 to 40% by weight of tannic acid and 20 to 40% by weight of an organic solvent at a temperature of 20°C to 30°C,
(b) adding 20 to 50% by weight of water to the lysate that has undergone the primary dissolving step, and stirring and mixing at a temperature of 35°C to 40°C to include a secondary dissolving step;
The second step of obtaining the B solution,
(1) nano silica sol (nano SiO ₂ sol) 20 to 30% by weight of the organic solvent and 20 to 30% by weight of water and 20 to 30% by weight of water to react at a temperature of 60 ℃ ~ 80 ℃,
(2) a polycondensation step of polycondensing at a temperature of 60°C to 80°C by adding 20 to 30% by weight of silicate while proceeding with the reaction;
The third step of mixing the A solution and the B solution is a method of manufacturing a rust inhibitor, characterized in that A solution: B solution is mixed in a weight ratio of 1: 3 to 5.
According to claim 4,
The method of manufacturing the rust inhibitor further comprises the step of mixing hydroxy propyl cellulose (HPC).
The method of claim 4 or 5,
The method of manufacturing the rust-preventing agent further includes mixing a heating material,
The heating material is a method of manufacturing a rust inhibitor, characterized in that at least one selected from gray silicon carbide (SiC) and green silicon carbide (SiGC).