KR101431358B1 - Corrosion-proofing coating composition and process for production thereof, and method for prevention of corrosion in steel material - Google Patents

Abstract

A system comprising a polymeric emulsion selected from a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion, and a nitrite salt, the compound comprising cement and an inorganic base material and a swelling agent.

Description

TECHNICAL FIELD [0001] The present invention relates to an anticorrosive coating composition, a method for producing the anticorrosive coating composition, a method for producing the anticorrosive coating composition, a method for producing the anticorrosive coating composition,

The present invention relates to an anticorrosive coating composition used as a base material for a surface of a steel material, a method for producing the anticorrosive coating composition, and a method for treating the steel material.

The present application claims priority based on Japanese Patent Application No. 2010-042285 filed on February 26, 2010, and Japanese Patent Application No. 2010-042298 filed in Japan on Feb. 26, 2010 And the contents are used here.

Steel structures such as steel structures and steel bridge are assumed to be used for a long period of time. As a result, these steel structures have been subjected to surface coating for the purpose of securing a good appearance and aesthetic appearance. Generally, the coating is composed of three layers of a lower coating for the purpose of preventing rusting, a top coating for the purpose of ensuring weatherability and aesthetic appearance, and a middle coating for improving the adhesion of the lower coating and the upper coating. The paint life is largely influenced by the coating material and the use environment, but under relatively severe circumstances, the modified epoxy coating is 6 years and the epoxy urethane coating is 10 years. Therefore, a plurality of repaints are required during the common period of the steel structure.

Here, the mechanism of rust generation will be described. When iron is exposed to rainwater or the like, the water adsorbed on the iron surface introduces electrons from the iron element and generates a chemical reaction with oxygen in the air to generate OH ^- . On the other hand, Fe ^{2 +, which} is deprived of electrons, dissolves in the water and combines with the generated OH ^- to become Fe (OH) ₂ and is oxidized to form FeOOH, Fe ₂ O ₃ .nH ₂ O, Fe ₃ O ₄ .nH ₂ O And so on.

As a method of preventing iron, there is known a method of keeping the surface of iron at alkaline and passivating it. In general, it is said that iron forms a passive layer of Fe ₂ O ₃ in a pH range of 9 to 12.5 and becomes stable. For example, Patent Document 1 discloses a technique for preventing the generation of rust by keeping the iron surface alkaline. In Patent Document 1, a compound in which a carbon fiber is added to a base material (main material) composed of a mixture of white cement and ultrafine silica, Discloses a surface coating agent comprising a water-soluble curing agent composed of a mixture of a butadiene copolymer and a cyclohexyl methacrylate copolymer.

Patent Document 2 discloses an invention of a pollution-free anti-corrosive coating composition comprising an alkali group-containing slag, mica, and aluminum phosphomolybdate produced in a refining process with respect to a resin solid content.

On the other hand, in Patent Document 3, a mortar made by mixing polymer cement, aggregate, water and a lithium nitrite solution is sprayed onto a predetermined portion of a concrete structure through a mortar spray nozzle The invention of a mortar spraying method is disclosed. In this method, the following reaction is caused by the action of nitrite ions (NO ₂ ^- ) of lithium nitrite (LiNO ₂ ) present in the mortar to form a passive film (Fe ₂ O ₃ ), and the generation of rust is prevented.

Further, Patent Document 4 discloses that nose formed at the interface between a green layer and a steel material (containing an anion adsorbent in the underground regulating material, which is an electrochemically replenishment of the anion portion by the erosion cells formed on the surface of the steel due to corrosion of the steel, The present invention discloses an invention of a lower limb adjusting member made of a steel material that actively removes anions in the lower limb.

Japanese Patent Laid-Open No. 5-155649 Japanese Patent Application Laid-Open No. 2002-80786 Japanese Patent Application Laid-Open No. 2007-177567 Japanese Patent Application Laid-Open No. 2004-299979

However, the surface coating agent described in Patent Document 1 uses carbon fibers which are high cost materials. In addition, since the film thickness is made thick (700 to 800 탆), the coating film is prevented from cracking and the effect of suppressing the diffusion of water and oxygen is enhanced and the life span of the coating film is prolonged. .

The pollution-free anti-corrosive coating composition described in Patent Document 2 has an excellent long-term rust-preventive property, but a passive film on the surface of a steel material formed by a component such as slag containing an alkaline group is likely to enter from a scratch portion caused by deterioration of coating film or external damage It is destroyed by the corrosion factor, rust proceeds in a short period, and its life is as short as 10 years.

On the other hand, in the invention described in Patent Document 3, when the passive film is damaged by some external factors, the passive film is rebuilt by the action of the nitrite ion. However, when the passive film is painted as a corrosion inhibiting material for a steel, nitrite is soluble, do. As a result, there is a problem with long-term corrosion resistance. In the invention described in Patent Document 4, an anion adsorbent such as a calcium-aluminum complex hydroxide, which is not consumed by the reaction of cement, is contained in a cementitious underpouring agent containing an aqueous epoxy resin as an admixture to suppress the occurrence of corrosion of the steel , The long-term corrosion resistance is not known.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a nitrile nitrile rubber composition capable of reducing nitrile nitrate salt as a rust preventive agent, A method for producing the same, and a method for treating steel.

The anticorrosive coating composition according to the present invention comprises a compound containing cement, an inorganic base material and a swelling agent, a polymer emulsion selected from a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion, and a nitrite.

With the above-described constitution, workability and durability as a coating material are ensured. Further, since the alkaline coating film is formed on the surface of the steel material, the surface of the steel material is passivated, and corrosion does not proceed. When the passive film (Fe ₂ O ₃ ) is damaged by some external factors, a nitrite ion (NO ₂ ^- ) reacts with Fe ^{2 +} and OH ^- to rebuild the passive film (Fe ₂ O ₃ ). As a result, the life of the steel structure can be greatly increased compared with the conventional art. In addition, by making the mass ratio of the cement to the inorganic bonsai be 1.0 to 1.4, a high-density structure can be constructed. As a result, the diffusion speed of the nitrite is lowered, and the rust inhibitive effect of the nitrite can be maintained for a long period of time. As a result, the number of times of re-application during the common period of the steel structure is reduced, and the cost for re-coating can be greatly reduced. On the other hand, when the mass ratio of cement to the inorganic bonsai is less than 1.0 or exceeds 1.4, the diffusion speed of nitrite can not be suitably lowered.

The styrene / butadiene copolymer and the acrylic / styrene copolymer all have good adhesion to the base, have little dependency on temperature, and have excellent elasticity even at a low temperature and a relatively high temperature range. As a result, a coating film excellent in water permeability and weather resistance can be obtained.

The synthetic resin of the cationic styrene-butadiene copolymerization system described in Patent Document 1 can be expected to have anticorrosive effect, but it is expected that the deformation capacity (elongation) of the coating film is 0.4%, the elongation when the bending axial force acts on the steel is 0.5% There is a problem such as coating film crack. In addition, the epoxy-based synthetic resin described in Patent Document 4 is generally said to have a smaller elongation than the synthetic resin of the cationic styrene-butadiene copolymerization system.

On the other hand, according to the present invention, in the case of employing a styrene / butadiene copolymer, it is preferable to use a styrene / butadiene copolymer in which the composition of the styrene / butadiene copolymer is changed (styrene content is reduced) Thereby obtaining a coating film having an elongation of 5% or more. In this connection, when the stability of the coating film is taken into account, the elongation percentage of the coating film formed by the anticorrosive coating composition according to the present invention is set to 5%, thereby sufficiently following the deformation of the steel structure. As another constitution, an acrylic / styrene copolymer was used as an anionic synthetic resin in order to promote the flow of nitrite ions (NO ₂ ^- ) toward the anode.

The amount of nitrite (solid content) used in the conventional polymer-cement mortar disclosed in Patent Document 3 and the like is such that if the blending ratio to the total composition is increased, the cement becomes abnormal. As a result, the amount of nitrite used was 5% by mass in the case of lithium nitrite and 1.25% by mass in the case of calcium nitrite. However, in order to maintain a long-term rust inhibitive effect with the application of paint, it is necessary to set the amount of nitrite to 2.5% by mass or more. Therefore, in the present invention, the amount of the nitrite is increased by increasing the amount of the styrene / butadiene copolymer to 5 mass% or more or by setting the amount of the acrylic / styrene copolymer to 6 mass% or more. When the amount of cement is set to 26% by mass or more, the coating film is allowed to have an alkaline atmosphere of pH 11.5 to 12.5, which makes it possible to reduce the undercoating treatment and to provide a long-term method. In addition, in order to secure the tensile strength, elongation following property and adhesion strength as a paint, the inorganic bonsai material and the swelling agent are contained in the compound.

The nitrite contained in the anticorrosive coating composition according to the present invention is preferably 2.5% by mass or more.

When the nitrite content is less than 2.5% by mass, the rust inhibitive effect is on the order of the epoxy resin coating, and rust occurs in the crosscut portion in the salt spray test 3000 hours. For example, when the amount of nitrite in the present invention is 3 mass%, the amount of nitrite is about 2.5 times that of the conventional coating.

When a styrene / butadiene copolymer emulsion is selected as the polymer emulsion, the nitrite contained in the anticorrosive coating composition is preferably 7.5% by mass or less.

When the nitrite content exceeds 7.5 mass%, the amount of the styrene / butadiene copolymer to be mixed with the styrene / butadiene copolymer is increased, and voids in the cement hydrate are increased. As a result, the moisture easily penetrates into the voids, and diffusion of nitrite in the cement hydrate is accelerated. As a result, a long-term rust prevention effect can not be expected.

When an acrylic / styrene copolymer emulsion is selected as the polymer emulsion, the nitrite contained in the anticorrosive coating composition is preferably 9.0 mass% or less.

When the amount of nitrite exceeds 9.0 mass%, the amount of water to be mixed with the acrylic / styrene copolymer is increased, and voids in the cement hydrate are increased. As a result, the moisture easily penetrates into the voids, and diffusion of nitrite in the cement hydrate is accelerated. As a result, a long-term rust prevention effect can not be expected.

In the present invention, the anticorrosive coating composition may contain 5 to 18 mass% of the styrene / butadiene copolymer. If the content of the styrene / butadiene copolymer is less than 5 mass%, the styrene / butadiene copolymer emulsion becomes less than 18 mass parts with respect to 100 mass parts of the cement, and the elongation and fracture strength of the coating film are not improved, do. As a result, coating film cracks tend to occur, and the rust from the cracks proceeds. On the other hand, when the content of the styrene / butadiene copolymer exceeds 18 mass%, the coating film has a deformation capacity that is more than necessary, while the coating film adhesion strength is insufficient and the coating film peeling occurs.

Alternatively, the anticorrosion coating composition may contain 6 to 24 mass% of the acrylic / styrene copolymer. If the content of the acrylic / styrene copolymer is less than 6% by mass, the acrylic / styrene copolymer emulsion is less than 11 parts by mass based on 100 parts by mass of the cement, and the elongation and fracture strength of the coating film are not improved, do. As a result, coating film cracks tend to occur, and rust in the cracked portion proceeds. On the other hand, when the content of the acrylic / styrene copolymer exceeds 24 mass%, the coating film has a deformation capacity that is more than necessary, while the coating film adhesion strength is insufficient to cause film peeling.

In the present invention, the anticorrosive coating composition contains 26 to 39% by mass of the cement, 20 to 28% by mass of the inorganic base material, and 0.5 to 1.5% by mass of the swelling agent.

When a styrene / butadiene copolymer emulsion is selected, the cement contained in the anticorrosive coating composition is preferably 26 mass% or more and 39 mass% or less.

When the cement content is less than 26% by mass, when the nitrite and the styrene / butadiene copolymer are appropriately mixed, the water cement ratio exceeds 1.4, and the required film strength is not obtained. Concretely, coating film peeling occurs due to lack of adhesion strength, and cohesive failure occurs due to insufficient compression strength.

On the other hand, if it exceeds 39% by mass, the required film strength can be expected, but the cement becomes excessive and the amount of shrinkage increases to cause cracks on the coated film surface.

When the acrylic / styrene copolymer emulsion is selected, the cement contained in the anticorrosive coating composition is preferably 26 mass% or more and 38 mass% or less.

When the cement content is less than 26% by mass, when the nitrite and the acrylic / styrene copolymer are appropriately mixed, the water cement ratio exceeds 1.0, and the necessary film strength is not obtained. Concretely, coating film peeling occurs due to lack of adhesion strength, and cohesive failure occurs due to insufficient compression strength. On the other hand, if the cement content exceeds 38% by mass, the required film strength can be expected, but the cement becomes excessive and the amount of shrinkage increases to cause cracks on the coated film surface.

If the inorganic bonsai is less than 20% by mass, the coating film becomes cement-rich and the probability of occurrence of cracks during drying increases. In addition, the yield of the coating film can not be secured due to an increase in the amount of the coating. On the other hand, if the amount of the inorganic bonsai exceeds 28 mass%, the amount of the aggregate becomes too large, the viscosity of the cement hydrate decreases, and the adhesive force of the bottom surface decreases.

The effect of the expanding agent can be expected when the appropriate amount of cement is used. If the amount of the swelling agent is less than 0.5% by mass, if the styrene / butadiene copolymer or the acrylic / styrene copolymer is small, the coating film becomes soft and it can not cope with shrinkage due to cement. On the other hand, when the styrene / butadiene copolymer or the acrylic / styrene copolymer is present in large quantities, the amount of the styrene / butadiene copolymer is inevitably increased, and the coating film becomes excessively loose and the effect of the swelling agent can not be expected. On the other hand, if it exceeds 1.5% by mass, the amount of SO ₃ (sulfur trioxide) in the compound increases and becomes close to the use limit value (8% by mass ratio of the large cement), which causes expansion cracks.

When a styrene / butadiene copolymer emulsion is selected as the polymer emulsion, the water content is preferably 13 to 42 mass%. Here, the water content is in the styrene / butadiene copolymer emulsion and in the aqueous solution of nitrite. If the water content is less than 13 mass%, 2.5 mass% of nitrite can not be ensured. If the moisture content exceeds 42 mass%, the nitrite exceeds 7.5 mass%, resulting in an excessive specification, and the cost is increased.

When an acrylic / styrene copolymer emulsion is selected as the polymer emulsion, the water content is preferably 12 to 43 mass%. Here, the water content is in the acryl / styrene copolymer emulsion and in the aqueous solution of nitrite. If the water content is less than 12 mass%, 2.5 mass% of nitrite can not be ensured. If the water content exceeds 43 mass%, the nitrite exceeds 9.0 mass%, which causes an excessive specification and an increase in cost.

In addition, in order to reduce the number of alumina and pinholes on the coated film surface, the inorganic inorganic material is at least one selected from silica, calcium carbonate, magnesium silicate, slag powder (steel slag powder, etc.) . During the summer construction, the clay powder is added to the methylcellulose thickener to prevent dry out (phenomenon in which hydration reaction is inhibited due to moisture being lost to the lower limb, causing hardening defects and poor adhesion). And the effect is further improved.

In the anticorrosive coating composition according to the present invention, when the cement is usually Portland cement, the nitrite is preferably lithium nitrite. When the nitrite is calcium nitrite, the cement is preferably blast furnace cement.

The clinker produced in the cement manufacturing process is mainly composed of elite, bellite, aluminate phase and ferrite phase. The present inventors have found that an aluminate phase in a clinker reacts with calcium nitrite to cause an abnormal condensation of the cement. Therefore, in order to prevent the abnormal condensation of the cement, when cement is usually Portland cement, lithium nitrite is used as the nitrite. In the case of using calcium nitrite as a nitrite, blast furnace cement was used to reduce the amount of aluminate phase and prevent the cement from agglomerating.

Further, when the blast furnace cement and lithium nitrite are combined, the coagulation time is prolonged, so that the coating material is stretched at the time of construction, making it difficult to secure the thickness of the coating film.

Also, the anticorrosive coating film formed by the anticorrosion coating composition is a anticorrosive coating film containing a compound containing cement, an inorganic bonsai and an expanding agent, a polymer selected from a styrene / butadiene copolymer or an acrylic / styrene copolymer, and a nitrite.

The anticorrosive coating film is a cured coating film containing 32.5 to 49 mass% of the cement (cement component), 25 to 35 mass% of the inorganic bonsai, 0.6 to 1.9 mass% The styrene / butadiene copolymer of 6 to 23 mass%, and the nitrite of 3.1 to 9.4 mass%, and further containing 7 to 12 mass% of crystal water, wherein the inorganic bonsai is selected from the group consisting of silica, Calcium carbonate, magnesium silicate, slag powder, and clay minerals.

Another form of the anticorrosive coating film is a anticorrosive coating film containing an acrylic / styrene copolymer as the polymer. The anticorrosive coating film contains 32.5 to 47.5 mass% of the cement (cement component), 25 to 35 mass% of the inorganic bonsai, 0.6 to 1.9 mass Styrene copolymer, 3.1 to 11.2% by mass of the nitrite, and 7.8 to 12% by mass of crystal water, wherein the inorganic bonsai material comprises silica, , Calcium carbonate, magnesium silicate, slag powder, and clay minerals.

The content of cement, swelling agent and nitrite in the composition of the coating film indicates the content of each raw material component of the coating film and the content of the crystal water corresponds to the amount of water introduced into the coating film by the hydration reaction with cement or the like .

In any of the above modes, the amount of water evaporated upon curing of the anticorrosive coating composition was about 20% of the total mass of the anticorrosive coating composition from the experimental results. Therefore, the component ratio of the anticorrosive coating film is obtained by dividing the component ratio of the anticorrosive coating composition by 0.8.

The method for preparing the anticorrosive coating composition according to the present invention is characterized in that the styrene / butadiene copolymer emulsion or the acrylic / styrene copolymer emulsion is added to the nitrite aqueous solution to prepare the anticorrosive coating composition, And a second step of adding the cement, the inorganic base material and the compound containing the swelling agent to the admixture liquid subjected to the preheating treatment.

Here, the term " cold pretreatment " means that a mixed solution obtained by adding a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion to an aqueous nitrite solution is stirred at a low speed for a predetermined time while maintaining a predetermined temperature. The predetermined temperature is suitably 30 to 60 DEG C, for example, about 40 DEG C, and the predetermined time is 3 to 10 minutes, for example, about 5 minutes. It is also preferable to add the compound to the admixture after allowing the admixture which has undergone the pre-warming treatment to stand for 5 to 10 days, for example, for about 7 days.

In the present invention, the mixed solution obtained by adding the styrene / butadiene copolymer emulsion or the acrylic / styrene copolymer emulsion to the nitrite aqueous solution is pre-treated at a constant temperature to adjust the viscosity of the admixture to a styrene / butadiene copolymer emulsion or acrylic / styrene copolymer emulsion- To about 1/40 of that of the first embodiment. As a result, a significant improvement in the kneading effect of the compound can be expected. In addition, it becomes a stable admixture in the long term, and long-term preservation becomes possible.

The method of the present invention may further comprise the steps of removing the loose rust on the surface of the steel material, applying the undercoating material comprising the anticorrosion coating composition to the surface of the steel material to form the undercoat layer, Is formed on the undercoating layer to form a topcoat layer.

The coating film layer according to the present invention is characterized in that the coating film layer is formed of a top coat layer made of a coating film having an elongation percentage of 5% or more and a base coat layer made of the anticorrosive coating film.

Here, the above-mentioned elongation percentage is determined based on the above-described "3. Method of Quality Test of Polymer Cement Coating Film Waterproofing Material" of "Reference Material 2, Polymer Cement Coating Waterproofing Construction Guideline (Instructions) Quot; test for tensile strength and elongation at break ".

In the present invention, since the undercoat layer is alkaline (pH 11.5 or more) due to the cement contained in the anticorrosive coating composition, a passive film (Fe ₂ O ₃ ) is formed on the surface of the steel to prevent the generation of rust Method function). As a result, it is unnecessary to adjust the surface of the steel material to a high degree, and the cost can be reduced. For example, it is only necessary to adjust the roughness of a three-kind kerene to remove the rust from the surface of the steel. If the passive film is damaged by any external factors, the nitrite is eluted and the passive film is rebuilt (self restoration function). In addition, a stencil / butadiene copolymer or an acrylic / styrene copolymer imparts flexibility to the undercoat layer to form a undercoat layer capable of following the deformation of the steel surface.

The elongation percentage of the anticorrosive coating film according to the present invention, as described above, is preferably 0.5% or more when the bending axial force is applied to the steel material. Therefore, in consideration of the stability of the coating film, The elongation percentage of the top coat film needs to be 5% or more.

The upper layer may be composed of a coating film containing at least one selected from an epoxy resin, a urethane resin, a polyurethane resin, an acrylic silicone resin, an acrylic urethane resin, a Hals hybrid resin and the like. The upper layer may be a single layer coating film or may be composed of two or more layers of coating films.

The total layer thickness of the upper layer is not particularly limited, but may be, for example, 60 to 130 탆. For example, it may be composed of a first layer having a layer thickness of 60 to 80 탆 and a second layer having a layer thickness of 20 to 40. Alternatively, it may be composed of a first layer having a layer thickness of 40 to 70 mu m and a second layer having a layer thickness of 30 to 40 mu m.

The anticorrosive coating composition of the present invention is a anticorrosive coating composition containing a compound containing a cement, an inorganic base material and a swelling agent, a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion, and a nitrite. A styrene / butadiene copolymer of 5 mass% or more or an acrylic / styrene copolymer emulsion of 6 mass% or more is contained in order to make the amount of nitrite to be 2.5 mass% or more. In addition, the cement amount of the entire composition is set to 26 mass% or more. As a result, the coating film is provided with an alkaline atmosphere having a pH of 11.5 to 12.5, thereby making it possible to reduce the substrate treatment and to provide a long-term method. In addition, since the cured paste after curing properly encloses the nitrite used as the rust preventing agent, the spreading speed of the nitrite is lowered, and the effect of the nitrite can be maintained for a long period of time.

Further, in the present invention, when preparing anticorrosive coating compositions, a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion is previously added to an aqueous nitrite solution, and the mixture is pre-treated at a constant temperature. As a result, it becomes possible to reduce the viscosity of the admixture to about 1/40 of the viscosity of the styrene / butadiene copolymer emulsion alone or the acrylic / styrene copolymer emulsion alone. As a result, a significant improvement in the kneading effect of the compound can be expected.

Further, in the present invention, since the undercoat layer becomes alkaline, a passive film is formed on the surface of the steel material, and the occurrence of rust is prevented. This makes it unnecessary to adjust the surface of the steel material at a high level. If the passive film is damaged by any external factors, the nitrite is eluted and the passive film is rebuilt. In addition, a stencil / butadiene copolymer or an acrylic / styrene copolymer imparts flexibility to the undercoat layer to form a undercoat layer capable of following the deformation of the steel surface.

Although the embodiments of the present invention are described below, the present invention is not limited to the following embodiments at all and includes other embodiments and modifications deemed to be within the scope of the claims .

[Shadow material]

The present invention relates to an anticorrosive coating composition for use as a base material for a surface of a steel material, which comprises a cement, an inorganic base material, and a swelling agent, which is prepared by adding a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion to a nitrite aqueous solution, By adding a compound containing the compound of formula (I). At this time, it is preferable that the styrene / butadiene copolymer is 5 to 18 mass% and the nitrite is 2.5 to 7.5 mass%. Alternatively, 6 to 24 mass% of the acrylic / styrene copolymer and 2.5 to 9.0 mass% of the nitrite are preferable.

In order to secure durability without deteriorating the rustproof quality and to secure a predetermined base coating thickness (200 to 650 mu m), it is preferable that the styrene / butadiene copolymer is 10 to 18 mass% and the nitrite is 3 to 4.5 mass% , Or 10 to 20 mass% of an acrylic / styrene copolymer and 4 to 6.5 mass% of a nitrite. In addition, if a mixed solution obtained by adding a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion to an aqueous nitrite solution is pretreated at a constant temperature, the nitrite can be easily increased.

When a styrene / butadiene copolymer is used, it is more preferable that the blending amount of the compound is 50 to 70% by mass of the entire composition. When an acrylic / styrene copolymer is used, it is more preferable to use 50 to 60% by mass of the entire composition.

Further, in order to prevent the coating film from cracking, it is more preferable that the content of the inorganic base material is 20 to 28 mass% and the amount of the expansion agent is 0.5 to 1 mass% in order to suppress the amount of SO ₃ (sulfur trioxide) in the coating film.

Nitrite is a substance that imparts a rust inhibitive effect. Lithium nitrite, sodium nitrite, potassium nitrite, calcium nitrite, magnesium nitrite, and barium nitrite can be used, but lithium nitrite and calcium nitrite have good compatibility with cement.

Cement maintains the coating film alkaline and has a function as a binder. The cement is not particularly limited, and various portland cements, various mixed cements, blast furnace cement, fly ash cement and the like can be used. When calcium nitrite is used for nitrite, blast furnace cement is preferably used to improve fluidity .

Inorganic bonsai strengthens the dispersibility and adhesion of the compound. As the inorganic bonsai, silica sand such as natural silica sand and regenerated silica sand, clay mineral, calcium carbonate or slag powder can be used. Among them, one or more kinds selected from calcium carbonate, magnesium silicate, slag powder and clay mineral .

When the compound is only cement and swelling agent, the film thickness can not be ensured and the coating film shrinks with cement hardening. For these reasons, it is necessary to add an inorganic bonsai to the anticorrosive coating composition. At this time, unless the particle size of the inorganic bonsai is about 1/3 of the minimum film thickness, a stable coating film can not be obtained. For this reason, the particle size distribution of the inorganic bonsai has a minimum film thickness of 200 μm and a ratio of the inorganic bonsai of 74 μm or less is 80% or more.

The swelling agent is used to prevent the drying shrinkage of the compound. As the swelling agent, commercially available ones such as anhydrous gypsum can be used.

In addition to the above-described materials, a water reducing agent for reducing moisture and improving fluidity, a thickening agent for increasing viscosity, and the like may be added as an admixture. When a styrene / butadiene copolymer is used, the amount of the admixture is preferably 0.4 to 0.8% by mass, more preferably 0.6% by mass. When an acrylic / styrene copolymer is used, the amount of the admixture is preferably 0.3 to 0.6% by mass, more preferably 0.4% by mass.

With respect to the painting using the anticorrosive coating composition according to the present invention, the epoxy resin coating, the alkali coating and the heavy painting, the expected life span of each coating is 30 years, 7 years, 8 years, 10 years, The total cost was calculated. When the total cost of using the anticorrosive coating composition of the present invention was 1, the epoxy resin coating was 5.0, the alkali coating was 4.1, and the heavy coating was 5.0. From this point of view, it can be seen that the use of the anticorrosive coating composition according to the present invention can significantly reduce the lifecycle cost of the steel structure.

[Sangdo]

The coating film formed on the undercoat layer made of the anticorrosive coating composition is required to have the following properties, to prevent the elution of nitrite, and to have excellent weather resistance. A combination of an epoxy resin, a urethane resin, or the like having high deformability can be used. Here, the top material having high weather resistance will be described. For example, a two-component mixed type coating material comprising a solution prepared by dissolving an acrylic silicone resin in a tablet-type medicinal agent as a main component and an isocyanate as a curing agent may be used as an upper layer material used for the upper layer directly formed on the lower layer . The mixing ratio of the main component and the curing agent is preferably 2 to 15 parts by mass per 1 part by mass of the curing agent.

In the above topcoat, an isocyanate group of the main OH group and a curing agent bind to each other to form a urethane crosslink in the molecular structure of the coating film, by using an acrylic silicone resin having excellent weatherability as a main component of the subject and mixing isocyanate as a curing agent. Thereby, the molecular structure of the coating film becomes a three-dimensional network structure, and the sealing property of the coating film is improved. That is, it is possible to prevent the nitrite contained in the undercoating layer from eluting into the topcoat layer. Further, when the urethane crosslinking is formed, the crosslinking density (the ratio of the number of crosslinking points relative to the total structural units) is set low and softened (by about H with pencil hardness), thereby ensuring compliance.

In addition, the top coat layer is required to have excellent weather resistance capable of maintaining gloss for a long period of time. Therefore, as another example of the top coat material used for forming the top coat layer, a two-pack coating type paint using a solution prepared by dissolving a Hals hybrid resin in a steel agent such as toluene or xylene as a main component and an isocyanate as a curing agent can be used. The mixing ratio of the base and the curing agent is preferably 2 to 15 parts by mass based on 1 part by mass of the curing agent, as in the case of the top coat.

The main component of the resin is a HALS hybrid resin, which is an acrylic polyol resin obtained by copolymerizing a hindered amine light stabilizer and cyclohexyl methacrylate. The hindered amine light stabilizer (hereinafter referred to as " HALS ") captures radicals generated by ultraviolet rays and detects an auto oxidation deterioration reaction of the coating film (when radicals are once generated, they react with oxygen in the air to generate radicals Thereby deteriorating the coating film). On the other hand, cyclohexyl methacrylate does not have a benzene skeleton which easily absorbs sunlight to generate radicals, and has high hydrophobicity. The HALS hybrid resin chemically bonds HALS to the resin to prevent bleeding out of the HALS, thereby suppressing the automatic oxidation deterioration reaction of the coating film for a long period of time. At the same time, the high hydrophobicity of cyclohexyl methacrylate improves the longevity of the coating film .

Further, by mixing the subject and the curing agent, the urethane crosslinking is formed in the molecular structure due to the bonding of the OH group of the subject and the isocyanate group of the curing agent, so that the molecular structure of the coating film becomes a three-dimensional network structure, and the sealability of the coating film is improved.

[Method of steel material]

Next, a method of treating the steel material according to an embodiment of the present invention will be described by taking, as an example, the re-coating of the eroded structure with corrosion.

(1) High-pressure water pressurized by a high-pressure water generator (not shown) at a water pressure of about 15 MPa to 25 MPa is sprayed from the nozzle toward the surface of the steel to adjust the surface of the steel material. The extent of the substrate adjustment is about 3 kerene (equivalent to SSPC-SP2 or SIS St2), that is, to remove the old film and horny rust to reveal the surface of the slip, . In addition, sandblasting or power tools may be used to adjust the substrate.

(2) A primer layer made of the aforementioned anticorrosive coating composition is applied to the surface of the steel material having the surface roughness adjusted. At this time, the thickness of the undercoat layer is set to 200 to 650 mu m. The target of drying time is about one day, but it varies depending on environmental conditions such as humidity.

(3) Mixing a solution prepared by dissolving an acrylic silicone resin in a medicinal agent and isocyanate and applying the agitated topsheet to the undercoating layer to form a first topcoat layer. At this time, the thickness of the first uppermost layer is set to 60 탆 to 80 탆. The target of drying time is about one day, but it varies depending on environmental conditions such as humidity.

(4) Mixing a solution prepared by dissolving a Hals hybrid resin in a luting agent and isocyanate and stirring the top layer material is applied on the first top layer to form a second top layer. At this time, the thickness of the second uppermost layer is set to 20 탆 to 40 탆. The target of drying time is about one day, but it varies depending on environmental conditions such as humidity.

The application method of the priming coat and the first and second priming coatings may be brush coating, roller coating, or spray coating. In the case of the rain after the application, the next coating is performed at intervals of about three days.

<Examples>

Hereinafter, embodiments of the present invention will be described.

[First Embodiment]

In the first embodiment, a styrene / butadiene copolymer was used.

[Combined cycle test]

A composite cycle test was conducted on a test piece coated with a base material and a top material on a steel plate having a strip-like surface subjected to a surface roughing treatment. Table 1, Table 2 and Table 3 show the material composition of the examples and reference examples in which the composite cycle test was conducted, and the characteristics of the topcoat material. Table 5, Table 6, Table 7 and Table 8 show the material composition and test results of the comparative example. Herein, the reference coating material used in the anticorrosive coating composition according to the present invention is a topcoat material having a coating film elongation of less than 5%. In each of the examples, reference examples and comparative examples, two pieces of test pieces were used. After applying a topsheet to each of the test pieces, the test pieces were cut on the surface of the test piece and cross cut with a cutter knife.

In Examples A1 to A6, lithium nitrite was used as the nitrite contained in the undercoat, and calcium nitrite was used in Examples A7 to A11. In Examples A1 to A6, the cement was ordinary Portland cement, and in Examples A7 to A11, blast furnace cement was used. At this time, as the inorganic bonsai, calcium carbonate and magnesium silicate and clay powder were combined in Example A1, A3 to A5, a combination of silica powder and clay powder in Example A8, and a slag powder (steel slag powder ) And clay minerals, slag in Example 2, calcium carbonate and magnesium silicate in Examples A6 and 9, silica sand in Example A7 and clay minerals in Example A10, respectively.

On the other hand, the upper layer has a two-layer structure composed of two different top materials for each example, and the total thickness is 80 占 퐉 or 100 占 퐉. The crosslinking density of the topsheet was obtained by relatively evaluating the crosslinking densities of Examples A1 to A11 with respect to the average value of the first upper layer and the second upper layer. Likewise, the elongation percentage of the topsheet material is an average value of the first topsheet layer and the second topsheet layer.

In Reference Examples A1 to A4, lithium nitrite was used for the nitrite contained in the underlaying material, and cement was usually made of Portland cement. In Reference Example A5, calcium nitrite was used for nitrite contained in the underlayment material, and cement was made of blast furnace cement. For the inorganic bonsai, reference examples A1, A4 and A5 are calcium carbonate and magnesium silicate, reference example A2 is a combination of slag and clay components, and reference example A3 is a combination of calcium carbonate and magnesium silicate and clay components did. On the other hand, regarding the top materials, reference examples A1 and A2 use epoxy resin, Reference example A3 uses medicinal silicone epoxy resin, and Reference examples A4 and A5 use modified silicone epoxy resin.

In the undercoats of Comparative Examples A1 to A3, Mighty CF made by Mighty Chemical Co., Ltd., which mainly contains white cement and ultrafine silica, was used. In the undercoats of Comparative Examples A4 and A5, Tomrick (registered trademark) made of Bushetics Co., Ltd., which has a silicone resin and zinc powder as its main components, was used. The undercoating materials of Comparative Examples A6 and A7 were alkaline paint, the undercoating material of Comparative Example A8 was a zinc rich paint, and the undercoating material of Comparative Example A9 was an epoxy resin paint. Comparative Examples A10 to A12 consisted of the same components as in the present invention but were blended in a ratio outside the scope of the present invention.

On the other hand, for the top materials of Comparative Examples A1 to A12, a chlorinated olefin-based coating material was used for Comparative Example A7 only, and an epoxy resin was used for the other comparative examples.

Comparative Examples A13, A14, A17 to A21, A23, A24, A29 and A30 used lithium nitrite as a nitrite contained in the underlayment material and Portland cement as a cement. In Comparative Examples A15, A16, A22, A25 to A28 and A31 to 34, calcium nitrite was used for the nitrite contained in the underlaying material, and blast furnace cement was used for the cement. In the comparative examples A13, A14, A16, A25 and A26, a combination of calcium carbonate and magnesium silicate and a clay component was used as the inorganic bonsai. In Comparative Example A27, a combination of a silica component and a clay component was used. Calcium silicate and magnesium silicate were used in Comparative Examples A15, A19, A20 and A32 to A34, silicate was used in Comparative Examples A17, A18 and A28, In Comparative Examples A21, A22 and A29, slag powder was used, and in Comparative Examples A23 and A24, clay powder was used.

On the other hand, the top materials of Comparative Examples A13 to A34 were all made of acrylic urethane resin and had a thickness of 180 탆.

The coating amount was set to 1.0 kg / m 2 for the undercoat material and 0.4 to 0.5 kg / m 2 for the topcoat material. The coating thicknesses in Tables 2, 5, and 7 are measured values by a film thickness meter.

In the combined cycle test, the cast spray test was conducted for 4 hours at 35 DEG C, followed by drying for 2 hours at 60 DEG C and a humidity of 50% and for 2 hours. The humidity test was conducted for 2 hours at a temperature of 50 DEG C and a humidity of 95% A total of 8 hours is set as one cycle, and a plurality of cycles are performed.

The cast spray test is a test in which the test solution is changed from a saline solution to a cascade solution in the salt spray test method according to JIS Z 2371. The cacous solution is an aqueous solution containing 40 g / L of sodium chloride and 0.205 g / L of cupric chloride and having a pH of 3.0 with acetic acid.

The humidity resistance test was conducted in accordance with JIS K 5600-7-3 moisture resistance (discontinuous condensation method).

The combined cycle test was conducted 200 times. In all of the examples, reference examples and comparative examples, rust occurrence state (rust-preventive effect) on the surface of two test pieces was evaluated on a scale of 10 out of 10 on the basis of the criteria shown in Table 9, The average was obtained. In addition, the comprehensive evaluation in Tables 4, 6, and 8 is a comprehensive evaluation of the rust prevention effect, the workability, and the followability and the weather resistance.

The following can be seen from these tables.

All of the examples a) have high anti-corrosive effect and some have poor workability, but they are highly evaluated highly.

b) All of the reference examples are excellent in rust prevention effect and workability, but are poor in followability because the elongation percentage of the upper layer is as low as less than 5%. As a result, the overall evaluation is low.

c) All of the comparative examples are low in rust prevention effect and low in comprehensive evaluation.

d) The composite evaluation of the embodiment using a topsheet having a high crosslinking density and an elongation percentage of 5% or more is high. In other words, it is understood that a paint having both sealability and inability to follow the coating film is preferable as a topsheet material.

[Mixing stability]

A mixed solution prepared by adding a styrene / butadiene copolymer emulsion to an aqueous solution of lithium nitrite and a mixed solution obtained by adding a styrene / butadiene copolymer emulsion to an aqueous solution of calcium nitrite were each subjected to a pretreatment immediately before and after 7 days of constant temperature pretreatment Are shown in contrast to Table 10. Here, the mass ratio of the aqueous nitrite solution to the styrene / butadiene copolymer emulsion is 1: 4. The viscosity was measured at a rotation speed of 20 rpm using a BH type viscometer. From the above table, it can be seen that no significant change was observed with respect to the concentration, viscosity and pH immediately after the pre-warming treatment and after 7 days of standing, and the properties were stable.

In addition, the viscosity of the mixed liquid is 40 to 50 mPa · s, and the fluidity is remarkably improved as compared with the viscosity of the styrene / butadiene copolymer emulsion alone of 600 to 800 mPa · s.

[Tensile strength test]

This test is to judge the tensile strength of the coating film. Table 11 shows the formulation of the anticorrosive coating composition of Example A12. The coating film requires a tensile strength of 0.5 to 1.0 N / mm &lt; 2 &gt; or more, but the tensile strength of Example A12 is 1.5 N / mm &lt; 2 &gt;

[Breaking ductility test]

In this test, the elongation at break of the coated film is judged. The blending of the examples is the same as in the tensile strength test. In order to follow the deformation of the base material, the elongation of 0.5% or more is necessary in the case of the steel material, but the elongation at break of the embodiment is 5%, so that the deformation of the base material can be sufficiently followed. In this regard, in the case of the conventional product, the elongation at break is 1.4%.

[Attachment strength test]

This test is to determine the degree of adhesion between the base material and the coating film. This meeting was carried out in accordance with JIS A 6203 &quot; Polymer Dispersion for Cement Admixture and Resin Type Powder Resin &quot;. Table 12 shows the formulation of the anticorrosive coating composition of Example A13. The adhesive strength of Example A13 was 1.1 N / mm 2, and the adhesion strength of the thin material (thin coating material) specified by JIS A 6916 was 0.5 N / mm 2 and the adhesion strength of the posterior material (thick coating material) was 1.0 N / mm 2.

[Second Embodiment]

In the second embodiment, an experiment was conducted using an acrylic / styrene copolymer.

[Combined cycle test]

A composite cycle test was conducted on a test piece coated with a base material and a top material on a steel plate having a strip-like surface subjected to a surface roughing treatment. Table 13, Table 14, and Table 15 show the material composition and the properties of the topcoat material of Examples and Reference Examples in which the composite cycle test was conducted. Table 17, Table 18, Table 19 and Table 20 show the material composition and test results of the comparative example. Here, as a reference material, the anticorrosive coating composition according to the present invention is a topcoat material having an elongation percentage of a coating film of less than 5%.

In each of the examples, reference examples and comparative examples, two pieces of test pieces were used. After applying a topsheet to each of the test pieces, the test pieces were cut on the surface of the test piece and cross cut with a cutter knife.

In Examples B1 to B6, lithium nitrite was used as the nitrite contained in the undercoat, and calcium nitrite was used in Examples B7 to B11. In Examples B1 to B6, cement was used as ordinary portland cement, and in Examples B7 to B11, blast furnace cement was used. In Example B1, B3 to B5, calcium carbonate and magnesium silicate were mixed with clay, Example B8 was combined with silica and clay, and Example B11 was mixed with slag powder (steel slag powder ) And clay minerals were used in Example B2, calcium carbonate and magnesium silicate in Examples B6 and B9, silica sand in Example B7 and clay minerals in Example B10, respectively.

On the other hand, the upper layer has a two-layer structure composed of two different top materials for each example, and the total thickness is 80 占 퐉 or 100 占 퐉. The crosslinking density of the top layer material is an average value of the first upper layer layer and the second upper layer layer, and the crosslink density of Examples B1 to B11 is relatively evaluated. Likewise, the elongation percentage of the topsheet material is an average value of the first topsheet layer and the second topsheet layer.

In Reference Examples B1 to B4, lithium nitrite was used as the nitrite contained in the underlayment, and cement was usually made of Portland cement. In Reference Example B5, calcium nitrite was used for the nitrite contained in the underlayment, and cement was made of blast furnace cement. For the inorganic bonsai, reference examples B1, B4 and B5 are calcium carbonate and magnesium silicate, reference example B2 is a combination of slag and clay components, and reference example B3 is a combination of calcium carbonate and magnesium silicate and clay components did.

On the other hand, regarding the top materials, reference examples B1 and B2 use epoxy resin, reference example B3 uses medicinal silicone epoxy resin, and reference examples B4 and B5 use modified silicone epoxy resin.

As the undercoats of Comparative Examples B1 to B3, Mighty CF made by Mighty Chemical Co., Ltd., which mainly contains white cement and ultrafine silica, was used. Comparative Examples B4 and B5 were made of Tomik Rik (registered trademark) made by Bushes Co., Ltd., having a silicone resin and a zinc powder as main components. The undercoating materials of Comparative Examples B6 and B7 were alkaline paint, the undercoating material of Comparative Example 8 was a zinc rich paint, and the undercoating material of Comparative Example B9 was an epoxy resin paint. In addition, Comparative Examples B10 to B12 consist of the same components as in the present invention, but the blend ratio is outside the scope of the present invention.

On the other hand, for the top materials of Comparative Examples B1 to B12, a chlorinated olefin-based paint was used for Comparative Example B7 only, and an epoxy resin was used for the other comparative examples.

In Comparative Examples B13, B14, B17 to B21, B23, B24, B29 and B30, lithium nitrite was used for the nitrite contained in the underlaying material and Portland cement was usually used for the cement. In Comparative Examples B15, B16, B22, B25 to B28 and B31 to B34, calcium nitrite was used for the nitrite contained in the underlaying material, and blast furnace cement was used for the cement. In addition, in the comparative examples B13, B14, B16, B25, and B26, calcium carbonate and a combination of magnesium silicate and a clay powder were used as the inorganic bonsai material. In Comparative Example B27, a combination of a silica powder and a clay powder was used. Calcium carbonate and magnesium silicate were used in Comparative Examples B15, B19, B20 and B32 to B34, silicate powder was used in Comparative Examples B17, B18 and B28, In Comparative Examples B21, B22 and B29, slag powder was used, and in Comparative Examples B23 and B24, clay powder was used.

On the other hand, the top materials of Comparative Examples B13 to B34 were made of a drug-containing acrylic urethane resin and had a thickness of 180 占 퐉.

The coating amount was set to 1.0 kg / m 2 for the undercoat material and 0.4 to 0.5 kg / m 2 for the topcoat material. The coating thicknesses in Tables 13, 17, and 19 are measured values by a film thickness meter.

In the combined cycle test, the casting spray test is carried out at 35 DEG C for 4 hours, followed by drying at 60 DEG C for 2 hours under a humidity of 50% and for 2 hours under 50 DEG C and humidity of 95% A total of 8 hours is set as one cycle, and a plurality of cycles are executed.

The cast spray test is a test in which the test liquid is changed from a saline solution to a cascade solution in the salt spray test method according to JIS Z 2371. The cacous solution is an aqueous solution containing 40 g / L of sodium chloride and 0.205 g / L of cupric chloride and having a pH of 3.0 with acetic acid. The humidity resistance test was conducted in accordance with JIS K 5600-7-3 moisture resistance (discontinuous condensation method).

The combined cycle test was conducted 200 times. The rust occurrence state (rust-preventive effect) on the surfaces of the two test pieces was evaluated on the basis of the criteria shown in Table 21 on the basis of the scores shown in Table 21 in all of the examples, the reference examples and the comparative examples. The average was obtained. The comprehensive evaluation in Table 16, Table 18, and Table 20 is a comprehensive evaluation of the rust prevention effect, the workability, the inability to follow and the weather resistance.

The following can be seen from these tables.

All of the examples a) have high anti-corrosive effect and some have poor workability, but they are highly evaluated highly.

b) All of the reference examples are excellent in rust prevention effect and workability, but are poor in followability because the elongation percentage of the upper layer is as low as less than 5%. As a result, the comprehensive evaluation is low.

c) All of the comparative examples are low in rust prevention effect and low in comprehensive evaluation.

d) The composite evaluation of the embodiment using a topsheet having a high crosslinking density and an elongation percentage of 5% or more is high. In other words, it is understood that a paint having both sealability and inability to follow the coating film is preferable as a topsheet material.

[Mixing stability]

Styrene copolymer emulsion in an aqueous solution of lithium nitrite and an admixture in which an aqueous solution of calcium nitrite and an acrylic / styrene copolymer emulsion were added to the aqueous solution were left to stand for 7 days immediately after the pre-warming treatment and the pre- Are shown in contrast to Table 22. Here, the mass ratio of the aqueous nitrite solution to the acrylic / styrene copolymer emulsion is 3: 4. The viscosity was measured at a rotation speed of 20 rpm using a BH type viscometer. From the table, it can be seen that no significant change was observed with respect to the concentration, viscosity and pH immediately after the pre-warming treatment and after 7 days of standing, indicating that the properties were stable.

In addition, the viscosity of each of the mixed liquids is 40 to 50 mPa · s, and the fluidity is remarkably improved as compared with the viscosity of the acrylic / styrene copolymer emulsion alone of 1500 to 1600 mPa · s.

[Tensile strength test]

This test is to judge the tensile strength of the coating film. Table 23 shows the formulation of the anticorrosive coating composition of Example B12. In the case of a coated film, a tensile strength of 0.5 to 1.0 N / mm &lt; 2 &gt; or more is required, but the tensile strength of Example B12 is 1.5 N / mm &lt; 2 &gt;

[Breaking ductility test]

In this test, the elongation at break of the coated film is judged. The blending of the examples is the same as in the tensile strength test. In order to follow the deformation of the base material, the elongation of 0.5% or more is necessary in the case of the steel material, but the elongation at break of the embodiment is 5%, so that the deformation of the base material can be sufficiently followed. In this regard, in the case of the conventional product, the elongation at break is 1.4%.

[Attachment strength test]

This test is to determine the degree of adhesion between the base material and the coating film. This meeting was carried out in accordance with JIS A 6203 &quot; Polymer Dispersion for Cement Admixture and Resin Type Powder Resin &quot;. Table 24 shows the formulation of the anticorrosive coating composition of Example B13. The bond strength of Example B13 was 1.1 N / mm 2, and the bond strength of the flake material specified in JIS A 6916 was 0.5 N / mm 2 and the bond strength of the after-treatment material was 1.0 N / mm 2.

&Lt; Industrial applicability >

The coating film formed on the surface of the steel material using the anticorrosive coating composition of the present invention has an alkaline atmosphere of pH 11.5 to 12.5. When a coating film layer made of such a coating film as the undercoat layer is formed, a passive film is formed on the surface of the steel material, and generation of rust is prevented. Further, since the nitrite is appropriately maintained by the cement paste, the rust inhibitive effect by the nitrite can be maintained for a long period of time. Further, flexibility is imparted to the undercoat layer by the polymer composed of the styrene / butadiene copolymer or the acrylic / styrene copolymer, and it becomes possible to follow the deformation of the steel surface. By these effects, it is not necessary to adjust the surface of the steel material to a high degree, and a long-time method becomes possible.

Claims (15)

A polymer emulsion comprising a compound containing cement, an inorganic base material and a swelling agent, an emulsion comprising an emulsion containing a styrene / butadiene copolymer or an emulsion containing an acryl / styrene copolymer, and a nitrite, Lt; RTI ID = 0.0 &gt;
Wherein the particle size distribution of the inorganic bonsai is 80% or more of the inorganic bonsai having a size of 74 탆 or less. The method according to claim 1, wherein the polymer emulsion is a styrene / butadiene copolymer emulsion,
By mass of the cement, 20 to 28% by mass of the inorganic bonsai, 0.5 to 1.5% by mass of the swelling agent, 5 to 18% by mass of the styrene / butadiene copolymer, 2.5 to 7.5% Including,
And 13 to 42 mass% of water, and the inorganic bonsai material is one or more kinds selected from silica, calcium carbonate, magnesium silicate, slag powder and clay powder. The method of claim 1, wherein the polymer emulsion is an acrylic / styrene copolymer emulsion,
By mass of the cement, 20 to 28% by mass of the inorganic powder, 0.5 to 1.5% by mass of the swelling agent, 6 to 24% by mass of the acrylic / styrene copolymer, and 2.5 to 9.0% Including,
And 12 to 43 mass% of water, and the inorganic bonsai material is at least one selected from siliceous powder, calcium carbonate, magnesium silicate, slag powder, and clay powder. The antifouling paint composition according to any one of claims 1 to 3, wherein the cement is blast furnace cement, and the nitrite is calcium nitrite. The antifouling paint composition according to any one of claims 1 to 3, wherein the cement is usually Portland cement, and the nitrite is lithium nitrite. A process for producing the anticorrosive coating composition according to any one of claims 1 to 3,
A first step of subjecting the nitrite aqueous solution to a preliminary temperature pretreatment with a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion to which the polymer emulsion is added; and a second step of subjecting the mixed solution obtained by pre- And a second step of adding the bons material and the compound containing the swelling agent. A method for producing the anticorrosive coating composition according to claim 4,
A first step of subjecting the nitrite aqueous solution to a preliminary temperature pretreatment with a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion to which the polymer emulsion is added; and a second step of subjecting the mixed solution obtained by pre- And a second step of adding the bons material and the compound containing the swelling agent. A method for producing the anticorrosive coating composition according to claim 5,
A first step of subjecting the nitrite aqueous solution to a preliminary temperature pretreatment with a styrene / butadiene copolymer emulsion or an acrylic / styrene copolymer emulsion to which the polymer emulsion is added; and a second step of subjecting the mixed solution obtained by pre- And a second step of adding the bons material and the compound containing the swelling agent. After removing the rust on the surface of the steel material, the undercoating material comprising the anticorrosion coating composition according to any one of claims 1 to 3 is applied to the surface of the steel material to form a undercoating layer, and a coating film having an elongation of 5% or more is formed Wherein the top layer is formed by applying a topsheet on the undercoat layer. A method for producing a steel sheet, comprising the steps of: applying a base material comprising the anticorrosion coating composition according to claim 4 onto a surface of the steel material to form a base layer, removing the loose rust on the surface of the steel material, To form a top layer. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; A method for producing a steel sheet, comprising the steps of: applying a base material comprising the anticorrosion coating composition according to claim 5 onto a surface of a steel material to form a base layer, To form a top layer. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; A cementitious coating film containing a compound containing cement, an inorganic bonsai material and a swelling agent, a polymer selected from a styrene / butadiene copolymer or an acrylic / styrene copolymer, and a nitrite,
Wherein the particle size distribution of the inorganic bonsai is 80% or more of the inorganic bonsai having a size of 74 탆 or less. 13. The method of claim 12, wherein the polymer is a styrene / butadiene copolymer,
From 32.5 to 49 mass% of the cement, from 25 to 35 mass% of the inorganic bonsai, from 0.6 to 1.9 mass% of the swelling agent, from 6 to 23 mass% of the styrene / butadiene copolymer, from 3.1 to 9.4 mass% of the nitrite Including,
Wherein the inorganic bonsai material comprises one or more selected from the group consisting of silica, calcium carbonate, magnesium silicate, slag powder, and clay mineral. 13. The method of claim 12, wherein the polymer is an acrylic / styrene copolymer,
From 32.5 to 47.5 mass% of the cement, 25 to 35 mass% of the inorganic bonsai, 0.6 to 1.9 mass% of the expanding agent, 7.5 to 30 mass% of the acrylic / styrene copolymer, 3.1 to 11.2 mass% of the nitrite Including,
Wherein the inorganic bonsai material comprises at least one selected from the group consisting of silicate, calcium carbonate, magnesium silicate, slag powder, and clay minerals. The coating film layer according to any one of claims 12 to 14, characterized in that the coating layer is formed of a top coat layer composed of a bottom coat layer made of the anticorrosive coating film according to any one of claims 12 to 14 and a coating film having an elongation percentage of 5% or more.