JP3784445B2 - Fire-resistant coating composition, method for forming fire-resistant coating film, and fire-resistant coating film - Google Patents

Description

【００３８】
【表２】

【００３９】
実施例
参考例５で得られた耐火塗料組成物に対してポリアマイド系揺変剤（共栄社油脂株式会社製のフローノンＳＨ−２９０）２５重量部をさらに添加し、得られた塗料の塗装作業性を調べた。塗装作業性は、ビスコメーターを用いて塗料の粘度を２５℃で１５０ポイズに調整後、これをサジングテスターを用いてガラス板に塗布し、当該ガラス板を垂直に起立させた際に塗料がタレ落ちない限界の塗布厚さを測定することにより調べた。結果は４，０００〜６，０００μｍであった。因に、参考例５で得られた耐火塗料組成物について同様に塗装作業性を調べたところ、結果は２５０〜３００μｍであった。
【００４０】
【発明の効果】
本発明の耐火塗料組成物は、塗膜形成性成分としてのアクリル樹脂、上述の耐火塗料用発泡性組成物およびポリアマイド系揺変剤を含んでいるので、膜厚を小さく設定しながら耐火性の高い有機系の耐火塗膜を実現することができる。
【００４１】
また、本発明に係る耐火塗膜の形成方法は、基材に対して上述の耐火塗料用組成物を塗布しているため、膜厚を小さく設定しながら耐火性の高い有機系の耐火塗膜を基材に形成することができる。
【００４２】
さらに、本発明に係る耐火塗膜は、上述の耐火塗料組成物を用いて形成されているので、膜厚が小さく設定されている場合でも耐火性が良好である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coating composition, a method for forming a coating film, and a coating film, and more particularly, to a fire-resistant coating composition, a method for forming a fire-resistant coating film, and a fire-resistant coating film .
[0002]
[Prior art]
It is known that the mechanical strength of a base material such as a steel frame or concrete, which is a structural driving body of a building, rapidly decreases due to high heat during a fire. Such a rapid decrease in the mechanical strength of the base material may cause a collapse of the building, so a fireproof coating is formed on the base material, and the mechanical strength of the base material at the time of a fire is rapidly increased. Various attempts have been made to prevent the decrease.
[0003]
Fireproof coatings used for the above-mentioned purposes are usually classified into inorganic type and organic type. Inorganic fire-resistant coatings are generally prepared by mixing inorganic binders such as cement with inorganic fibrous materials such as rock wool and lightweight aggregates such as vermiculite, and kneading with water to prepare a paste or slurry. is there. On the other hand, the organic fireproof coating is a paint and generally contains a film-forming resin component and a foaming agent (for example, JP-A-5-70540 and JP-A-5-86310). Such a fire-resistant coating film made of an organic fire-resistant paint foams in the event of a fire due to the action of a foaming agent contained therein, exhibits a heat insulating effect, and can prevent the substrate from being exposed to high temperatures.
[0004]
By the way, the inorganic fireproof coating as described above is usually set to a thick film of about 1 to 3 cm with respect to the base material. When the fireproof coating becomes such a thick film, the weight of the base material increases, so that the structural strength of a building, particularly a high-rise building, needs to be sufficiently increased in consideration of the weight of the fireproof coating. On the other hand, the above-mentioned organic fire-resistant paint foams and expands in the event of a fire, so even when a fire-resistant coating film of a few millimeters is formed, it has the same fire resistance as that of an inorganic fire-resistant coating. It can be demonstrated. For this reason, when an organic fireproof paint is used, good fire resistance can be achieved without increasing the structural strength of the building as in the case of using an inorganic fireproof coating. Therefore, considering the structural strength of the building, it is advantageous to use an organic type fireproof coating.
[0005]
[Problems to be solved by the invention]
In order to increase the fire resistance of the above-described organic fire-resistant paint, the component ratio of the fire-resistant paint is usually adjusted or the film thickness of the paint film is set large. However, according to the former method, the fire resistance of the coating film is only slightly improved, and there is a limit to increase the fire resistance. On the other hand, according to the latter method, the fire resistance of the coating film increases as the film thickness increases. For example, if the film thickness of the refractory coating is set to about 1.5 to 2.0 times the normal value, the fire resistance can be increased by about 50%. However, when the film thickness of the fire-resistant coating film is increased as described above, it is necessary to use a large amount of the fire-resistant paint, which is costly and not economical.
[0006]
An object of the present invention is to improve fire resistance without increasing the film thickness of an organic fire-resistant coating film.
[0007]
[Means for Solving the Problems]
The fire-resistant paint composition according to the present invention includes an acrylic resin as a film-forming component, a foaming agent, and a polyamide thixotropic agent. Here, the foaming agent contains low-temperature expandable graphite and a phosphoric acid compound. In this fire-resistant paint composition, the foaming agent is usually set to a mixing ratio of 10/100 to 25/100 by weight ratio (A / B) of the low-temperature-expandable graphite (A) and the phosphoric acid compound (B). And in the range of 110 to 500 parts by weight with respect to 100 parts by weight of the solid content of the film-forming component. The foaming agent further contains, for example, a foaming nitrogen-containing compound. This fire resistant paint composition may further contain a carbonizing agent. Moreover, this fireproof coating composition may further contain extender pigments .
[0008]
The formation method of the fire-resistant coating film which concerns on this invention includes the process of apply | coating the fire-resistant coating composition of this invention with respect to a base material.
[0010]
The fire-resistant coating film according to the present invention is formed using the fire-resistant coating composition of the present invention .
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Foamable composition for fire-resistant paint The foamable composition for fire-resistant paint used in the present invention is used for an organic fire-resistant paint, and foams when the fire-resistant coating film by the fire-resistant paint is exposed to high heat. It expands to provide heat resistance to the fireproof coating.
[0012]
This foamable composition contains low-temperature-expandable graphite and a phosphoric acid compound. Low-temperature-expandable graphite is a graphite intercalation compound having a crystal structure in which hexagonal network planes of carbon elements are stacked, and various substances inserted between layers of the hexagonal network planes. When such a graphite intercalation compound is heated at a high temperature, various substances inserted between the layers of the hexagonal mesh plane are decomposed and gasified, and the interlayer can greatly expand in the direction perpendicular to the layer surface by the pressure.
[0013]
Such graphite intercalation compound, for example, be stirred by adding mixed acid of sulfuric acid to a powder such as natural graphite or artificial graphite oxidizing agent is prepared by inserting a sulfuric acid between layers of graphite layer crystal it can. As the oxidizing agent, various general oxidizing agents such as nitric acid can be used.
[0014]
In the present invention, the above-mentioned low-temperature expandable graphite can be expanded at a lower temperature than general expandable graphite exhibiting expansion performance at about 1,000 to 1,200 ° C., specifically about 200 to 500. Graphite that can expand at ℃, more preferably 250 to 300 ℃ is used. Examples of such low-temperature expandable graphite include expandable graphite (grade No. 8099, 8099-LTE, 8099-LTE-u, 194, etc.) manufactured by Chuo Kasei Co., Ltd.
[0015]
Although the phosphoric acid compound used for the foamable composition for fireproof paints is not particularly limited, it is generally orthophosphoric acid, polyphosphoric acid, ammonium phosphate, melamine phosphate, or ammonium polyphosphate. However, it is preferable to use what coated ammonium polyphosphate with the melamine resin at the point which can form a fire-resistant coating film with favorable water resistance and fire resistance. In addition, a phosphoric acid compound can also use 2 or more types together.
[0016]
Such a phosphoric acid compound acts as a dehydration catalyst for dehydrating organic substances in the refractory coating components when subjected to a high temperature of about 300 ° C. or higher, thereby promoting the formation of carbides and burning the coating. Can be suppressed. At the same time, a fireproof inorganic phosphoric acid film can be formed by itself and the fire resistance of the fireproof coating can be improved.
[0017]
The foamable composition for fireproof coatings may contain a foamable nitrogen-containing compound in addition to the above-mentioned low-temperature-expandable graphite and phosphate compound. As the foamable nitrogen-containing compound, various compounds can be used as long as they can generate a large amount of gas such as nitrogen or ammonia when heated. For example, melamine, dicyandiamide, azodicarbonamide, urea, etc. are used. It is done. In addition, a foamable nitrogen-containing compound can also use 2 or more types together.
[0018]
When such a foamable nitrogen-containing compound is heated, a large amount of gas such as nitrogen or ammonia is generated, whereby combustion of the fire-resistant coating film can be more effectively prevented. Moreover, the carbide | carbonized_material produced | generated by combustion of a fireproof coating film can be expanded further, and, thereby, the heat insulation of a fireproof coating film can be improved more.
[0019]
In the foamable composition for fire-resistant paint, the mixing ratio of the above-mentioned low-temperature-expandable graphite (A) and phosphoric acid compound (B) is preferably 10/100 to 25/100 by weight ratio (A / B), 100 to 21/100 is more preferable. When the ratio of the low temperature expandable graphite is smaller than 10, sufficient heat insulation may not be imparted to the fireproof coating film. On the other hand, when the ratio of the low-temperature expandable graphite exceeds 25, the mechanical strength of the fire-resistant coating film decreases. In addition, the denseness of the foamed fire-resistant coating film is lowered, and as a result, the heat insulating property of the fire-resistant coating film may be lowered.
[0020]
Moreover, when the foamable composition for fireproof paint contains the above-mentioned foamable nitrogen-containing compound, the mixing ratio is preferably set to 100 to 600 parts by weight with respect to 100 parts by weight of low-temperature-expandable graphite, 200 to More preferably, it is set to 400 parts by weight. When this ratio is less than 100 parts by weight, foaming during heating becomes insufficient, and it is difficult to obtain a sufficient effect by using a foamable nitrogen-containing compound. On the other hand, when it exceeds 600 parts by weight, the denseness of the foamed fire-resistant coating film is lowered, and on the contrary, the heat insulating property of the fire-resistant coating film may be lowered.
[0021]
Fire-resistant paint composition The fire-resistant paint composition of the present invention contains a film-forming component and the above-mentioned foamable composition for fire-resistant paint as a foaming agent.
The coating film-forming component used in the present invention is a so-called resin component, and an acrylic resin is preferable because coating workability can be improved as compared with the case where a coating film-forming component such as a polyurethane resin or an epoxy resin is used. . As the acrylic resin, for example, styrene-acrylic resin or vinyl acetate-acrylic resin can be used. When an acrylic resin having a glass transition temperature of −15 to −50 ° C. is used, a flexible fireproof coating can be formed.
[0023]
The molecular weight of the above-mentioned film-forming component is preferably about 80,000 to 200,000 in terms of weight average molecular weight. When the molecular weight is less than 80,000, the fire-resistant coating film of the fire-resistant coating composition of the present invention tends to sag when heated, and the coating film may fall off from the substrate and may not exhibit heat insulation. On the other hand, when the molecular weight exceeds 200,000, painting workability, particularly spray painting workability may be deteriorated.
[0024]
The fire-resistant paint composition of the present invention usually contains 110 to 500 parts by weight, preferably 250 to 350 parts by weight of the above-mentioned foaming agent with respect to 100 parts by weight of the solid content of the above-mentioned film-forming component. When the ratio of the foaming agent is less than 110 parts by weight, the fireproof coating film according to the composition of the present invention is not sufficiently foamed during heating, and the coating film is less likely to exhibit sufficient heat insulation and heat resistance. On the other hand, when the proportion of the foaming agent exceeds 500 parts by weight, the fireproof coating film is excessively foamed during heating, and the mechanical strength of the coating film and the adhesion to the substrate are lowered. Moreover, the denseness of the fire-resistant coating film after foaming may be reduced, and the heat resistance of the fire-resistant coating film may be insufficient.
[0025]
The foaming agent used in the fire resistant coating composition of the present invention may contain a foaming nitrogen-containing compound in the proportion described above with respect to the low-temperature expandable graphite for the reasons described above. In this case, the mixing amount of the foaming agent is preferably set to 30 to 100 parts by weight and more preferably set to 50 to 80 parts by weight with respect to 100 parts by weight of the solid content of the film-forming component. When the mixing amount of the foaming agent is out of the above range, the same disadvantage as described above may occur.
[0026]
Moreover, the fireproof coating composition of the present invention may contain a carbonizing agent. This carbonizing agent is a component for forming a carbonized layer on a heated fire-resistant coating film that is dehydrated by a phosphoric acid compound that functions as a dehydration catalyst, which is a component of the foaming agent. When such a carbonizing agent is included, the fire resistant coating composition of the present invention can form a fire resistant coating film with better fire resistance.
[0027]
As the carbonizing agent, a general one used for conventional fireproof paints can be used. Specifically, a polyhydric alcohol having a quaternary carbon atom, for example, pentaerythritol, dipentaerythritol, tetrapentaerythritol, or the like is used.
[0028]
The carbonizing agent is usually used in an amount of 30 to 100 parts by weight, preferably 50 to 80 parts by weight, based on 100 parts by weight of the solid content of the film-forming component. When the amount is less than 30 parts by weight, a sufficient effect due to the addition of the carbonizing agent cannot be obtained, and the fire resistance of the fire-resistant coating film is hardly sufficiently increased. On the other hand, when the amount exceeds 100 parts by weight, when the refractory coating is heated, the coating is significantly softened, and the sagging of the coating may occur to lose the fire resistance function.
[0029]
The fireproof coating composition of the present invention contains a polyamide thixotropic agent in addition to the various components described above . Moreover, extender pigments, such as titanium dioxide, may be included. The fire-resistant paint composition of the present invention containing a polyamide thixotropic agent has a coating workability significantly improved as compared with the case where an acrylic resin and a polyamid thixotropic agent are not used as a film-forming component. The sagging drop of the coating composition applied on the surface can be improved by 2,000 to 3,000%. In addition, the addition amount of a polyamide-type thixotropic agent is normally set to 1-5 weight part with respect to 100 weight part of solid content of a film-forming component.
[0030]
Fire-resistant coating film The fire-resistant coating film of the present invention is formed using the above-mentioned fire-resistant coating composition. When forming a fire-resistant coating film using the above-mentioned fire-resistant paint composition, the paint composition is applied to a base material, such as steel frame or concrete, which is a structural driving body of a building. As a coating method, a general method such as brush coating or spray coating can be employed, but it is preferable to employ a spray coating method that allows relatively thick coating.
[0031]
In addition, since the above-mentioned fire-resistant paint composition improves coating workability significantly as described above, a fire-resistant coating film having a required film thickness can be easily formed even if the number of times of coating is small. Accordingly, in this case, an increase in cost due to an increase in the number of times of coating can be prevented, so that a fireproof coating can be formed at a lower cost.
[0032]
Moreover, when forming a fire-resistant coating film using the fire-resistant coating composition containing the acrylic resin whose glass transition temperature is -15 to -50 degreeC as a film-forming component as mentioned above, the said fire-resistant coating film is nonwoven fabric, It can also be formed on a flexible sheet-like material such as aluminum foil. In this case, the sheet-like material can be wound around the base material so that the fire-resistant coating film is located on the outside, and thus it becomes possible to impart fire resistance to the base material.
[0033]
The film thickness of the fire-resistant coating film of the present invention is usually set to about 0.5 to 4.0 mm. When the film thickness is less than 0.5 mm, the fire-resistant coating film may not exhibit sufficient fire resistance. On the other hand, when the film thickness exceeds 4.0 mm, it is difficult to exert a fire resistance effect commensurate with it, which is not economical. Thus, since the fire-resistant coating film of the present invention can exhibit high heat resistance even when the film thickness is set small, it is difficult to apply an excessive load to the base material of the building.
[0034]
The fire-resistant coating film of the present invention foams and expands by about 20 to 50 times when exposed to the high heat during a fire, and eventually forms a carbonized layer. This carbonized layer exhibits good heat insulation, and can effectively suppress the mechanical strength of the base material from being reduced by high heat.
[0035]
【Example】
Reference Examples 1-6 and Comparative Example 1
Film-forming components and low-temperature expandable graphite shown in Table 1, ammonium polyphosphate as a phosphate compound (Hostafram AP462 manufactured by Hoechst Japan Ltd.), melamine as a foamable nitrogen-containing compound, dipentaerythritol as a carbonizing agent (Dipentalite 300M manufactured by Guangei Chemical Co., Ltd.) and titanium dioxide (Taipaque CR95 manufactured by Ishihara Sangyo Co., Ltd.) as an extender pigment were mixed at a ratio shown in Table 2 to prepare a fireproof coating composition.
[0036]
The obtained fire resistant coating composition was applied to a blasted iron plate having a size of 300 × 300 × 3.2 mm coated with a rust preventive coating so as to have a dry film thickness of 2 mm to form a fire resistant coating film. This fireproof coating was heated in a gas incinerator based on the standard heating curve defined in JIS A 1304, and the time until the temperature of the back surface of the blasted iron plate reached 450 ° C. or higher (fireproof time) was measured. The results are shown in Table 2. The longer this time, the better the fire resistance of the fire resistant coating film.
[0037]
[Table 1]

[0038]
[Table 2]

[0039]
Example
25 parts by weight of a polyamide thixotropic agent (Flonon SH-290 manufactured by Kyoeisha Yushi Co., Ltd.) was further added to the fireproof coating composition obtained in Reference Example 5 , and the coating workability of the resulting coating was investigated. . The paint workability is adjusted by adjusting the viscosity of the paint to 150 poise at 25 ° C using a viscometer, and then applying this to a glass plate using a sagging tester. It investigated by measuring the coating thickness of the limit which does not sag. The result was 4,000 to 6,000 μm. By the way, when the paint workability of the fireproof coating composition obtained in Reference Example 5 was examined in the same manner, the result was 250 to 300 μm.
[0040]
【The invention's effect】
The fire-resistant paint composition of the present invention contains an acrylic resin as a film-forming component, the above-mentioned foamable composition for fire-resistant paint, and a polyamide thixotropic agent . High organic fireproof coating can be realized.
[0041]
In addition, since the method for forming a fire-resistant coating film according to the present invention applies the above-described composition for fire-resistant paint to a base material, an organic fire-resistant paint film having high fire resistance while setting the film thickness small. Can be formed on a substrate.
[0042]
Furthermore, since the fire-resistant coating film according to the present invention is formed using the above-mentioned fire-resistant paint composition, the fire resistance is good even when the film thickness is set small.

Claims (7)

An acrylic resin as a film-forming component;
A blowing agent ;
Including a polyamide thixotropic agent,
The foaming agent contains low-temperature expandable graphite and a phosphoric acid compound.
Refractory paint composition.   In the foaming agent, the mixing ratio of the low-temperature-expandable graphite (A) and the phosphoric acid compound (B) is set to 10/100 to 25/100 by weight ratio (A / B), and the coating agent is used. The fire-resistant paint composition according to claim 1, which is contained in an amount of 110 to 500 parts by weight based on 100 parts by weight of the solid content of the film-forming component.   The fireproof coating composition according to claim 1 or 2, wherein the foaming agent further contains a foamable nitrogen-containing compound.   The fire-resistant paint composition according to claim 1, 2 or 3, further comprising a carbonizing agent. The fireproof coating composition according to claim 1, 2, 3, or 4 , further comprising an extender pigment . Including a step of applying the fire resistant coating composition according to any one of claims 1 to 5 to a base material,
A method for forming a fireproof coating.   A fire-resistant coating film formed using the fire-resistant paint composition according to any one of claims 1 to 5.