KR100688254B1 - Antifire painting composition and its usage - Google Patents

Abstract

The present invention relates to a low-shrinkable, oil-based foamable refractory coating composition that is applied to the surface of the steel structure, such as to exhibit a fire resistance performance and to the preparation of a coating film prepared using the same, using an acrylic microgel resin together with an oily alkyl-modified acrylic resin It is a low shrinkable oil-based paint that is obtained by using it. It exhibits excellent fire resistance performance that can be applied as a fireproof coating material for 1 hour according to the fire resistance test method of the building structure part specified in Korean Industrial Standard KS F 2257, and no shrinkage occurs during foaming. Therefore, coating it on the surface of mineral wool boards, cables, trays, concrete, steel, wood, etc. can impart excellent fire resistance to the coating.

Description

Foaming fireproof coating composition and method for imparting fire resistance to a coating material using the same {Antifire painting composition and its usage}

The present invention relates to a foamed refractory paint composition and a method for imparting fire resistance to a coating material using the same, and more particularly, to a low shrinkage and oil-based foamable refractory paint composition which is applied to a surface of an iron structure and the like to exhibit fire resistance. It relates to a prepared coating film preparation.

Refractory paint is a paint that provides time to extinguish a fire or to save lives by protecting buildings and the like from fire and blocking or delaying access of steel to high temperature during a fire.

In addition, the refractory structure refers to a structure that can be reused by a simple repair after a fire as well as having a fire resistance to withstand high temperatures in the event of a fire.

On the other hand, the low carbon steel used in the construction steel structure has a critical temperature of about 540 ℃, the strength is usually reduced to about 60% above the critical temperature, so the steel frame in order to prevent the decrease in strength of the steel frame and the damage caused by human life in case of fire in the building Fireproof coating is carried out.

By the way, the fire resistant structure used for steel fireproof coating to date is representative of rock wool or vermiculite-based material such as la coat in this field. However, in recent years, the use of rock wool or vermiculite is expected to be regulated, and users are avoiding the use of these materials due to dust generation, poor aesthetics and poor working environment. . Therefore, the use of relatively environmentally friendly refractory paints is increasing.

A foamable refractory paint is a paint in which a dry coating layer foams when exposed to heat to form a carbonized layer. The carbonized layer protects the coating (steel) from flame and combustion heat for a predetermined time. The carbonized layer itself is finally combusted, but it takes some time to combust, so the influence of the subject becomes small.

In general, a variety of basic performance is required for the foamed refractory paint to properly function to protect the steel structure in case of fire. First, in order to have sufficient thermal insulation, foaming is smooth and the thickness of the foamed coating film must be higher than a certain level. If the foam thickness is thin, sufficient insulation cannot be obtained. Second, the density of the foam coating should be high enough for effective insulation. Even if the thickness of the foam coating film is high, if the density of the coating film is low, it is impossible to effectively prevent the penetration of heat from the outside. Third, even foaming should occur without foaming due to shrinkage during foaming. When cracks are generated in the foam coating, heat is introduced into the steel frame through the crack generating portion, and the heat insulation of the other parts is not useful.

On the other hand, the general oil-based foaming refractory paint is formed by including a blowing agent, a catalyst, a carbonizing agent, a pigment, an additive, and an oily solvent in a resin such as an oil-based acrylic resin.

However, such an oil-based foamed refractory paint is satisfactory in terms of foaming rate and foam coating density, but there is a problem that shrinkage occurs during foaming and cracks are generated.

Accordingly, the present inventors have studied to develop a fireproof coating that can exhibit effective thermal insulation properties by suppressing shrinkage and cracking caused by foaming while having a foaming rate and foam coating density equal to or higher than that of a conventional foamable fireproof coating system. During the effort, the present invention was found to be able to satisfy the above requirements as a result of introducing a new shrinkage inhibiting resin in the conventional refractory coating system.

Accordingly, it is an object of the present invention to provide a foamed refractory coating composition having a foaming ratio of a certain level and having a suitable density of the foam coating, and in particular, foaming can occur even without cracking due to shrinkage.

The foamable refractory coating composition for achieving the above object is made by adding a blowing agent, a catalyst, a carbonizing agent, a pigment, an additive and an oily solvent to the resin, wherein the resin is an oil-based alkyl modified acrylic resin and an acrylic emulsion resin, wherein the oil-based alkyl The modified acrylic resin is 5 to 35% by weight of the total composition, and the acrylic emulsion resin is characterized by containing 1 to 25% by weight of the total composition.

The present invention will be described in more detail as follows.

The oil-based foaming refractory paint of the present invention is designed to exhibit excellent foaming rate (measured by the ratio of the thickness of the foamed film in the state of foaming completed to the normal dry film thickness before foaming).

To this end, in the present invention, the acrylic copolymer and the dispersible resin are suitably used to suppress the shrinkage of the foam coating to obtain a very efficient thermal insulation effect.

Looking at the low-shrink oil-based foaming refractory coating composition according to the present invention in detail.

(1) resin

The resin exhibits durability at room temperature in the dry coating film and changes the coating film to a flow state when exposed to high temperature heat so that the coating film is properly foamed when gas is generated. Such resins are alkyl-modified acrylic copolymers, which have good durability such as chemical resistance, weather resistance, and flexibility, exhibit excellent water resistance, have a glass transition temperature in the range of -20 to 60 ° C, and have a weight average molecular weight of 5,000 to 90,000. It is an oil-based resin which has a value.

If the glass transition temperature of the oil-based resin is less than -20 ℃, the point of the viscosity of the resin decreases due to heat is too early to obtain a sufficient foaming rate, and if it exceeds 60 ℃, the point of viscosity decrease is too late and also sufficient foaming rate You won't get it.

In addition, when the molecular weight of the oil-based resin is less than 5,000, the wear resistance and water resistance of the coating film is poor, and evenly foamed coating film cannot be obtained. If the molecular weight is 90,000, the workability and smoothness of the paint are poor, and the foaming rate of the foam coating film is decreased. do.

Such oil-based alkyl-modified acrylic copolymers are 90-100 based on the total monomer weight of at least one monomer of an acrylic monomer having an ethylenically unsaturated group such as methyl methacrylate, butyl methacrylate, butyl acrylate, and ethyl acrylate as monomers. Copolymerized using a weight percent, and optionally copolymerized using at least 10% by weight of at least one acrylic monomer containing a hydroxyl group (-OH) or an acid group (-COOH), such as acrylic acid, hydroxypropyl methacrylate Alkyl modified acrylic copolymer.

Such oil-based alkyl-modified acrylic copolymer is contained in 5 to 35% by weight based on the total weight of the total coating composition, if the content is less than 5% by weight, the durability of the dry-curing coating film is poor and exceeds 35% by weight It is not preferable because the foaming rate is lowered and the coating film is peeled off during the foaming so that normal fire resistance cannot be exhibited. Therefore, Preferably oily acrylic resin is contained in 7 to 28 weight%.

On the other hand, the present invention includes another resin in addition to the alkyl-modified acrylic copolymer as described above, which is a dispersion resin having a shrinkage inhibiting action.

The oil-based resin for shrinkage suppression is not an ordinary solution polymerization type resin but an acrylic emulsion resin synthesized by an emulsion polymerization method. In general, the emulsion resin has different physical properties and types depending on the type of core resin forming the emulsion particles. The emulsion resin used in the present invention is acrylic acid, methacrylic acid, hydroxyethyl acrylate, and hydroxypropyl as the core resin. One or more selected from acrylic monomers including acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, styrene, and the like are used in an amount of 70 to 99% by weight based on the total monomer weight. An acrylic copolymer using 1 to 30% by weight of the diacrylate-based and / or triacrylate-based monomers containing at least 1% by weight relative to the total weight of the acrylic emulsion resin monomer is used.

Here, examples of the diacrylate- or triacrylate-based monomers include ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, polyethylene glycol 400 diacrylate, and triphenyl glycol di Acrylate, divinyl ethane, vinyl methacrylate, glycerin trimethacrylate, trimethylol propane triacrylate, trimethylol ethane triacrylate, pentaerythritol trimethacrylate, and the like. The acrylate increases the crosslinking degree of the resin while remaining in the resin and contributes to stabilization of the core resin. Also, the high crosslinking degree makes it possible to achieve a more dense coating surface when forming a dry coating film, so that the moisture absorption of the dry coating film has a great effect on the foaming performance. Will be reduced. Examples of such acrylic emulsion resins include AQ-24 of AKZO and the like. These resins are mixed with the above-mentioned oily alkyl-modified acrylic copolymer at an appropriate ratio to be evenly distributed between the skeletons of the alkyl-modified acrylic copolymer when forming a dry film, resulting in uniform foaming during foaming, resulting in shrinkage or cracking. Will be suppressed.

If the content of the acrylic emulsion resin that plays such a role is less than 1% by weight based on the total weight of the total composition, shrinkage and cracking occur during foaming, and when the content exceeds 25% by weight, the foaming rate is lowered, thereby preventing normal fire performance. desirable. Therefore, the shrinkage type dispersion resin can be used in an amount of 1 to 25% by weight, preferably 2 to 20% by weight.

Thus, when a foaming agent, a carbonizing agent, a pigment, an additive, an oily solvent, etc. which are added to the conventional foamable refractory paint are added to the resin of the oil-based alkyl modified acrylic resin and the acrylic emulsion resin, the foamable refractory paint of the present invention can be obtained. The components are as follows.

(2) foaming agent

The blowing agent decomposes at a high temperature to react with the carbonizing agent and the catalyst to form a carbonized layer and generates a gas during the reaction to serve to allow the carbonized layer to foam properly. Such blowing agents include melamine, dicyandiamide, urea, glycine, and the like.

If the blowing agent is used in less than 5% by weight based on the total weight of the composition, the formation of the carbonized layer is poor and the gas generated is insufficient, so that the carbonized layer is weakly foamed. It is not preferable that the carbonized layer cracks due to the excessive ejection of gas before foaming, so that normal fire resistance cannot be exhibited. Therefore, the content of the blowing agent is 5 to 25% by weight, preferably 8 to 20% by weight.

(3) catalyst

The catalyst decomposes at a high temperature to promote the reaction of the carbonizing agent and the blowing agent while releasing gas, and at the same time, participates in the reaction to form a carbonized layer. Such catalysts include primary ammonium phosphate, secondary ammonium phosphate, ammonium phosphite, melamine phosphate, dimelamine phosphate, melamine pyrophosphate (melamine pirophosphate), tricrecyl phosphate (tricrecyl phosphate) and the like.

When the catalyst is less than 13% by weight based on the total weight of the total composition, the reaction with the carbonizing agent and the blowing agent is not smooth. If the catalyst is more than 45% by weight, the foaming rate is lowered, and thus the fire resistance is lowered. Therefore, the catalyst is contained at 10 to 40% by weight, preferably at 15 to 30% by weight.

(4) carbonization

The carbonizing agent serves to form a carbonized layer that exhibits fire resistance by reacting with the blowing agent at a high temperature. Such carbonization agents include pentaerythritol, dipentaerythritol, tripentaerythritol, tripentaerythritol, sorbitol, trimethylolpropane, trimethylolpropane and trimethylolpropane. trimethylolpropane) etc. are mentioned.                     

If the carbonizing agent is used at less than 5% by weight based on the total weight of the total composition, the chemical reaction with the blowing agent is insufficient, making it difficult to form a suitable carbonized layer. If the carbonizing agent is more than 25% by weight, the foaming rate is lowered, which is undesirable.

Therefore, the carbonizing agent is used at 5 to 25% by weight, preferably at 7 to 17% by weight.

(5) Pigment

Pigments are generally used to impart color to all paints, and in addition to the purpose of imparting color to refractory paints, they also serve to improve fire resistance.

If the pigment is less than 3% by weight based on the total weight of the entire refractory coating composition, the coloring power is insufficient, and it is difficult to form a uniform pore layer inside the foam coating during the foaming process, resulting in a low density of the foam coating. It is not preferable because the foaming rate is poor and the fire resistance is lowered.

Therefore, the pigment is used to be 3 to 15% by weight, preferably 4 to 10% by weight.

(6) additives

As an additive, a thickener, a dispersant, an antifoaming agent, a plasticizer, and the like may be mixed at an appropriate ratio to achieve an optimum paint and coating performance. Such additives are preferably used in an amount of 3 to 15% by weight based on the total weight of the entire coating composition. Do.

(7) Oil-based solvent

The oil-based solvent is used to maintain the stable state of the paint and to facilitate the painting workability, if the content is less than 10% by weight based on the total weight of the total coating composition, painting is very difficult, 40% by weight If the excess solids in the paint settles and hardens, and the thixotropy (搖 變性) falls, and if you raise the back coat during painting, the paint flows down and it becomes very difficult to obtain the desired dry coat thickness.

Such an oil-based solvent is used so that it is 10 to 50% by weight, preferably 15 to 40% by weight based on the total weight of the entire composition.

In the case of general foamed refractory paints, the dry hardened coating film is exposed to high temperature heat by a fire or the like to form a carbonized layer, and shrinkage and cracks caused by non-uniform foaming during the foaming reaction act as a factor to lower the thermal insulation of the foamed coating film.

However, the foamed refractory paint according to the present invention is an acrylic emulsion resin, which is a dispersible resin, is mixed in an appropriate proportion in the paint, so that the resin effectively suppresses the shrinkage as described above to maintain the fire resistance performance for a long time. do.

On the other hand, the solid content of the above-mentioned oil-based alkyl-modified acrylic resin in the final coating film is present in an amount ranging from 10 to 30% by weight based on the total weight of the solid of the paint composition, workability, flowability, storage properties and It is preferable from the viewpoint of general coating material properties such as water resistance and abrasion resistance after dry coating film formation.

Referring to the foaming process of the low-shrink oil-based foaming refractory paint having a composition as described above is as follows.

(Foaming stage 1)

When heat is applied to the dry coating surface due to the occurrence of a fire, the coating film is converted into a fluid state when the organic component (especially oil-based resin, etc.) is above the softening point. This state means that the coating film is prepared in a state suitable for starting foaming.

(Expansion stage 2)

As the temperature of the coating rises, the catalyst, blowing agent and carbonizing agent and other organic components are decomposed and various gases are released. At this time, the emitted gas is slightly different depending on the components decomposed in the coating film, but is usually vapor, ammonia, carbon dioxide, etc., and they push out components such as the resin in the fluid state, naturally forming a foam layer in the coating film. The coating film starts to foam.

(3rd stage of foaming)

As foaming of the coating continues, the surface layer of the foamed coating starts to carbonize. Initially, expansion and carbonization proceed simultaneously, but as carbonization increases over time, the expansion of the coating gradually slows down, and after a certain time, only carbonization proceeds without foaming. The thickness of the foam layer thus formed is 50 to 150 times the initial dry coating thickness, and as a result of the foaming, the density of the carbonized layer is lower than that of the initial coating film.

(4 stages of foaming)

The foam layer continues to carbonize until the entire white is finally white, preventing external heat from reaching the workpiece.

Through the foaming process as described above, the foaming rate is 50 to 150 times, and the foamed coating film is almost free from damage due to shrinkage. The expanded foamed coating has no dropping or blowing of the foamed coating due to the flame, Is a major factor in effectively blocking heat transfer from high temperature heat to steel structures.

The present invention can exhibit an efficient heat insulating effect as a low dry coating thickness by combining the excellent foaming ratio and uniformity of the coating film as described above.

The low shrinkable oil-based foamed refractory paints obtained according to the present invention can be used in general buildings and factories used by many people, such as schools, hospitals, department stores, etc., and can be used where fire resistance such as ships and marine structures is required. It can be used for various purposes such as automobiles, aircrafts, mobile houses.

In particular, it can be used as paint for one-hour fireproof coatings on pillars and beams of factory buildings and dangerous goods storage and treatment facilities according to the fire resistance test method according to the notice of Ministry of Construction and Transportation.

That is, the low shrinkable oil-based foamed refractory paint obtained in accordance with the present invention can be applied to a surface such as mineral wool board, cable, tray, concrete, steel wood, etc. to impart fire resistance.

At this time, it is preferable to apply | coat so that the thickness of the dried film may be 0.5-3.0 mm.

The coating method is not particularly limited, and methods such as brush painting, air spray coating, airless spray coating, roller coating, and the like can be used.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the scope of the present invention is not limited thereto. In the following Examples and Comparative Examples, 'parts' means 'parts by weight'.                     

Preparation Example 1 Preparation of Alkyl Modified Acrylic Copolymer

After heating 35 parts by weight of xylene, an oil solvent, to 80 ° C. in a sand dune flask, 13 parts by weight of methyl methacrylate, 25 parts by weight of isobutyl methacrylate, 5 parts by weight of butyl acrylate, 7 parts by weight of ethylhexyl acrylate and benzoyl fur 0.4 parts by weight of oxide was mixed well, and then added dropwise to the four-necked flask over 3 to 3.5 hours. After aging for about 1 hour, 15 parts by weight of xylene and 0.1 part by weight of benzoyl peroxide were mixed well, followed by dropwise addition, and aged for 1 hour to obtain an alkyl-modified acrylic copolymer. The alkyl-modified acrylic copolymer thus obtained has a glass transition temperature of 23 ° C. and a weight average molecular weight of 12,000.

Example 1

23 parts of oil-based solvents were put into a container capable of producing a paint, and 22 parts of an alkyl-modified acrylic copolymer obtained according to Preparation Example 1, 5.0 parts of an acrylic emulsion resin (AQ-24, product of AK), chlorinated paraffin ( 5.0 parts of chlorine content (70%) was sequentially added, followed by low speed stirring until a uniform state was obtained. When the uniform state was reached, 4.3 parts of titanium dioxide (TiO ₂ ), 24.4 parts of ammonium polyphosphate, 7.8 parts of dipentaerythritol, and 7.1 parts of melamine were added sequentially as a pigment in a slow stirring state, followed by stirring until a uniform state was obtained. After high-speed dispersion, a low shrinkage, oil-based foamed refractory paint was prepared.

Example 2

Instead of using 24.4 parts of ammonium polyphosphate, 7.8 parts of dipentaerythritol, and 7.1 parts of melamine, the above-mentioned procedure was carried out except that 23.6 parts of ammonium polyphosphate, 4.4 parts of dipentaerythritol, 4.4 parts of monopentaerythritol, and 7.3 parts of melamine were used. In the same manner as in Example 1 was prepared a low shrinkage, oil-based foaming refractory paint.

Example 3

Instead of using 24.4 parts of ammonium polyphosphate, 7.8 parts of dipentaerythritol, 7.1 parts of melamine, except that 18.7 parts of ammonium polyphosphate, 6.1 parts of dipentaerythritol, 4.5 parts of melamine, and 5.8 parts of melamine pyrophosphate were used. In the same manner as in Example 1 was prepared a low shrinkage, oil-based foaming refractory paint.

Comparative Example 1

Ammonium polyphosphate 24.4 parts, dipentaerythritol 7.8 parts, melamine 7.1 parts, alkyl-modified acrylic copolymer 22 parts, acrylic emulsion resin 5.0 parts, chlorinated paraffin (70% chlorine) 5.0 parts instead of using the cloned Oily foaming refractory fired by the same method as Example 1, except that 5.0 parts of paraffin (70% chlorine), 24.1 parts of ammonium polyphosphate, 7.6 parts of dipentaerythritol, 7.0 parts of melamine, and 22 parts of alkyl-modified acrylic copolymer were used. The paint was prepared.

Experimental Example 1

Fire resistance performance and water resistance tests were performed on the refractory paints prepared according to Examples 1 to 3 and Comparative Example 1.

At this time, the fire resistance test was applied to the H-beam, the water resistance test was applied to the general iron specimens so that the thickness of the dry cured coating film is 0.90 ~ 1.05mm, fire resistance performance test and water resistance test of the dry coating film was carried out by the following method.

1) Fire resistance test

This test is to confirm the fire resistance performance of fire resistant coatings by coating them with structural coatings such as beams, columns, walls, etc. of general buildings, factory buildings, hazardous materials storage and treatment facilities.

After installing six thermocouples on the H beam at equal intervals, paint it with fireproof paint and conduct heating test for 1 hour under the standard heating condition of KS F 2257, and the foam coating of fireproof paint transfers heat from the surrounding heat to the test body. It is to assess whether there is a performance that blocks the degree of efficiency effectively.

At this time, the standard heating test shall be carried out in the designated furnace that can satisfy the standard heating temperature conditions. As specified in KS F 2257, the standard heating temperature shall be 1 mm in diameter with the performance of 0.75 or higher specified in KS C 1602. CA thermocouples are measured. When testing beams and columns, at least three to eight thermocouples are installed to measure the temperature of each part.

In this test, six thermocouples were installed at equal intervals on the test body, and the temperature of each site was measured.

In addition, the temperature change over time of the standard heating conditions and the actual heating temperature over time in the furnace in the test under such conditions were compared in Table 1 below.

The fire resistance test is based on the fire resistance test method of the building structure part specified in Korean Industrial Standard KS F 2257. For beams and columns, according to the National Construction Laboratory No. 58842-207, which was newly established in 1994, the average temperature is 538 ℃ The temperature is specified below 649 ℃.                     

Hour Standard heating temperature of KS F 2257 Actual heating temperature at test 5 540 536 10 705 695 15 760 757 20 795 787 25 820 814 30 840 833 35 860 855 40 880 875 45 895 893 50 905 910 55 915 918 60 925 928

This test is a test to confirm the applicability as a 1 hour fireproof coating material. The test is conducted for 1 hour according to the fire resistance test method of the building structure part specified in Korean Industrial Standard KS F 2257. It should be maintained below 649 ℃ to become a fireproof coating applicable as a fireproof coating for 1 hour.

2) water resistance test

After coating the iron specimen with refractory paint and drying it sufficiently, record the time when abnormality such as swelling, cracking, peeling occurs after completely immersing the test specimen in a tank containing water with sufficient air supply.

The fire resistance and water resistance test results evaluated in the same manner as shown in Table 2 below.

Example Comparative Example 1 Remarks One 2 3 Dry coating crack resistance Good Good Good usually Visual observation Fire resistance test (℃) 10 minutes 210 201 204 227 Test conditions KS F 2257 (average temperature) 20 minutes 281 272 273 294 30 minutes 333 325 326 350 40 minutes 379 376 375 416 50 minutes 435 424 428 488 60 minutes 486 481 482 570 Appearance of foam coating during fire resistance test Good Good Good Contraction phenomenon Visual observation Strength of foam coating Great Great Great Great Tactile observation Crack and Shrinkage Good Good Good Partial cracking Visual observation Water resistance test (hours) 82 76 72 68 Water immersion

From the results in Table 2, the foamable refractory paint composition according to Examples 1 to 3 according to the present invention has a one-hour fire resistance performance result and the appearance and foaming of the foamed coating film compared to the coating composition of Comparative Example 1 without using an acrylic emulsion resin. It can be seen that the uniformity of the coating film is much better. In particular, it can be seen that no shrinkage or the like occurs in the foam coating.

As described above, the low shrinkage oil-based foaming fireproof paint obtained by using an acrylic emulsion resin together with an oil-based alkyl-modified acrylic resin according to the present invention is according to the fire resistance test method of the building structure part specified in Korean Industrial Standard KS F 2257. Excellent fire resistance performance that can be applied as a one-hour fireproof coating, and shrinkage does not occur when foaming, so coating it on the surface of mineral wool boards, cables, trays, concrete, steel, wood, etc. can give excellent fire resistance .

Claims (10)

In a foamable refractory coating composition formed by adding a blowing agent, a catalyst, a carbonizing agent, a pigment, an additive and an oily solvent to a resin, The resin is an oil-based alkyl-modified acrylic resin and an acrylic emulsion resin, wherein the oil-based alkyl-modified acrylic resin is 5 to 35% by weight of the total composition, the acrylic emulsion resin is characterized in that it is contained in 1 to 25% by weight of the total composition Effervescent refractory paint composition. According to claim 1, The oil-based alkyl-modified acrylic copolymer is used at 90 to 100% by weight based on the total monomer weight of at least one monomer selected from methyl methacrylate, butyl methacrylate, butyl acrylate and ethyl acrylate At least one acrylic monomer optionally containing a hydroxyl group (-OH) or an acid group (-COOH), such as acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate and hydroxypropyl methacrylate resin It is obtained by copolymerization using less than 10% by weight, a foamed refractory coating composition characterized in that the glass transition temperature is -20 ~ 60 ℃ and the weight average molecular weight of the alkyl-modified acrylic copolymer of 5,000 to 90,000. The acrylic emulsion resin according to claim 1, wherein the acrylic emulsion resin is a shrinkage inhibiting oil-based resin which is synthesized by emulsion polymerization and has emulsion particles in the resin, and includes a diacrylate monomer and a triacrylate monomer containing two or more ethylene unsaturated groups. A foamable fire-resistant coating composition comprising all or each in an amount of 1 to 30% by weight based on the weight of monomers of the total acrylic emulsion resin. The foaming agent of claim 1, wherein the blowing agent contains 5 to 25% by weight of one or more selected from the group consisting of melamine, dicyandiamide, urea, and glycine. Foamable fireproof coating composition, characterized in that. The catalyst of claim 1, wherein the catalyst is primary ammonium phosphate, secondary ammonium phosphate, ammonium phosphite, melamine phosphate, dimelamine phosphate , Melamine pirophosphate and tricrecyl phosphate (tricrecyl phosphate) at least one member selected from the group consisting of 10 to 40% by weight of the total paint composition foamable refractory coating composition characterized in that it contains. The method of claim 1, wherein the carbonizing agent is pentaerythritol, dipentaerythritol, tripentaerythritol, sorbitol, trimethylolpropane, trimethylolethane And trimethylolpropane (trimethylolpropane) at least one member selected from the group consisting of 5 to 25% by weight of the total paint composition. The foamable refractory coating composition according to claim 1 or 2, wherein the oil-based alkyl-modified acrylic resin is present in an amount ranging from 10 to 30% by weight based on the total weight of solids of the entire paint composition. . A coating composition obtained according to claim 1 is applied to a surface to be coated to impart fire resistance. 9. The method of claim 8, wherein the surface to be coated is selected from the group consisting of mineral wool boards, cables, concrete, steel and wood. 9. The method of claim 8, wherein the coating composition is applied to the surface to be coated so that the thickness of the dry cured coating film is 0.5 to 3.0 mm.