JPH0825809B2 - Refractory coatings with bentonite and hydroxide compounds - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fireproof coating material having improved fireproof performance.

[0002]

2. Description of the Related Art Conventionally, asbestos and rock wool-based fire-resistant coating materials have been dominated by fire-resistant coating materials by the spraying method. Wood is being developed.

[0003]

[Problems to be Solved by the Invention] Ministry of Construction Notification No. 2999
No., JIS A1304 stipulates a fire resistance performance standard for a fire resistant coating material used for a steel frame building in which beams and columns can have a fire resistant structure. The standard is to perform a 1-hour fire resistance test, a 2-hour fire resistance test, and a 3-hour fire resistance test on the beam portion and the column portion, and a beam that has been subjected to a fireproof coating material in a furnace heated to about 1000 ° C. The internal steel frame temperature of the pillar is
This means that the average temperature should not exceed 350 ° C in a predetermined time.

The general performance of the current non-asbestos and non-rock wool type fire-resistant coating materials is that the fire-resistant coating material has a thickness of 20 mm in the 1-hour fire-resistant test in the pillar portion and 30 mm in the 2-hour fire-resistant test.
The time fire resistance test is about 40 mm. That is, the thickness satisfying the 3-hour fire resistance test is about 40 mm, and with this thickness, it is not possible to spray to a predetermined thickness at one time, and since it has to be sprayed twice, the working efficiency in spraying work is considerably deteriorated.

It is an object of the present invention to provide a fireproof coating material having a thinner thickness and a high fireproof performance which satisfies the required fireproof performance.

[0006]

The refractory coating material according to the present invention is formed from bentonite, a water of structural decomposition of a hydroxide compound, and water of crystallization by the decomposition endothermic action of the hydroxide compound during heating. The effect of delaying the heat conduction during heating of the non-combustible gas layer due to steam gas can be obtained in a wide temperature range due to the difference in the reaction temperature of bentonite and hydroxide compound, thereby achieving higher fire resistance performance. Is.

It is composed of bentonite 5 to 500 parts by weight and hydroxide compound 2 to 100 parts by weight of hydraulic cement.
Its gist is to have a composition of 0 to 800 parts by weight. Further, it is desired that the carbonate compound is contained in an amount of 20 to 800 parts by weight. Further, it is desired that the water glass is contained in an amount of 5 to 300 parts by weight. Furthermore, 5 to 5 weight of inorganic lightweight aggregate
It is desirable to include 500 parts by weight. Furthermore, it is desired that the inorganic fiber is contained in an amount of 1 to 50 parts by weight. Furthermore, it is desired that the re-emulsified synthetic resin powder is contained in an amount of 1 to 300 parts by weight.

(Explanation of Specific Structure) Specific examples of the hydraulic cement include Portland cement, alumina cement, silica cement, blast furnace cement, fly ash cement, and sulfate resistant cement. The hydraulic cement is used for the purpose of improving the adhesive strength of the fire-resistant coating material to the steel frame under high temperature conditions and improving the mechanical strength of the fire-resistant coating material. Bentonite has silica / alumina as a main component, and specific examples thereof include calcium-based bentonite and montmorillonite in montmorillonite group minerals. Bentonite achieves the effect of improving the fire resistance due to the endothermic effect when decomposing by heating during refractory and the effect of delaying heat conduction due to the formation of a water vapor gas layer, and the effect of improving the surface strength of the fire resistant coating material after heating. Is. Further, since bentonite has thixotropy, it can be expected to prevent sagging during spraying work. The blending ratio is 5 to 500 parts by weight, preferably 50 to 300 parts by weight, based on 100 parts by weight of hydraulic cement. If the blending ratio of bentonite is below the lower limit, decomposition endothermic action due to heating during refractory and delay of heat conduction due to formation of steam gas layer cannot be expected, and if above the upper limit, decomposition due to heating during refractory occurs. It is not preferable because the endothermic effect and the effect of delaying heat conduction due to the formation of the water vapor gas layer cannot be further obtained, and cracks may occur.

Specific examples of the hydroxide compound include aluminum hydroxide ((Al (OH) ₃ )) and gibbsite. The hydroxide compound can be expected to have an endothermic effect by decomposing by heating during fireproofing and an effect of delaying heat conduction due to formation of a water vapor gas layer. The blending ratio is 20 to 800 parts by weight, preferably 50 to 500 parts by weight, based on 100 parts by weight of hydraulic cement. If the compounding ratio of the hydroxide compound is below the lower limit, the decomposition endothermic action due to heating during fireproofing and the effect of delaying heat conduction due to the formation of the steam gas layer cannot be expected, and if above the upper limit, heating during fireproofing No further effect can be obtained by the decomposition and endothermic action by the above and the action of delaying the heat conduction due to the formation of the water vapor gas layer.

Specific examples of the carbonate compound include calcium carbonate (CaCO ₃ ) and magnesium carbonate (MgC).
O ₃ ) and the like. The carbonate compound can be expected to have an endothermic action by decomposing by heating during refractory and an action of delaying heat conduction due to formation of a carbon dioxide layer. The mixing ratio is 20 to 80 with respect to 100 parts by weight of hydraulic cement.
It is 0 part by weight, but preferably 50 to 500 parts by weight.

Specific examples of the water glass include those belonging to the first and second types of sodium metasilicate and in the form of powder or granules. Similar to hydraulic cement, water glass is for the purpose of improving the adhesive strength of the fire-resistant coating material to the steel frame at high temperature and the mechanical strength of the fire-resistant coating material, and further improving the surface strength and makeup of the fire-resistant coating material. It is used for the purpose of improving the sex. The mixing ratio is 5 to 300 parts by weight, preferably 30 to 200 parts by weight, based on 100 parts by weight of hydraulic cement.

Specific examples of the inorganic lightweight aggregate include obsidian perlite and pearlite perlite. The inorganic lightweight aggregate is used for the purpose of reducing the weight and reducing the thermal conductivity of the fireproof coating material of the present invention. The mixing ratio is 5 to 5 with respect to 100 parts by weight of hydraulic cement.
The amount is 00 parts by weight, preferably 30 to 120 parts by weight. If the content ratio of the inorganic lightweight aggregate is less than the lower limit value, the weight reduction of the fire resistant coating material and reduction of thermal conductivity cannot be expected, and if it is more than the upper limit value, the mechanical strength of the fire resistant coating material deteriorates. become.

Specific examples of the inorganic fiber include alkali glass fiber, ceramic fiber and the like. The inorganic fiber is used for the purpose of preventing the fireproof coating material of the present invention from falling off or peeling off during fireproofing. The mixing ratio is 1 to 50 parts by weight with respect to 100 parts by weight of hydraulic cement, and preferably 2 to 10 parts.
Parts by weight. If the blending ratio is below the lower limit, the above-mentioned action of the fire-resistant coating material cannot be expected, and if it is blended above the upper limit, no further effect can be obtained.

As the re-emulsified synthetic resin powder, vinyl acetate copolymer-based re-emulsified synthetic resin powder can be preferably used as a specific example. The addition of the re-emulsified synthetic resin powder can be expected to improve the adhesive strength of the fire-resistant coating material to the steel frame at room temperature and the surface strength of the fire-resistant coating material. The mixing ratio is 1 to 300 parts by weight, preferably 5 to 100 parts by weight, based on 100 parts by weight of hydraulic cement. If the blending ratio of the re-emulsified synthetic resin powder is less than the lower limit value, the improvement of the adhesive strength of the fire resistant coating material to the steel frame cannot be expected, and even if it is added above the upper limit value, there is no further effect, rather the fire resistant coating material Detract from the fire resistance of.

[0015]

The fireproof coating material in the present invention is bentonite,
Decomposition endothermic action during heating of the hydroxide compound, bentonite by this reaction, structural water of the hydroxide compound, and the action of delaying heat conduction during heating of the non-combustible gas layer due to steam gas generated from crystal water, Due to the difference in the reaction temperature between bentonite and the hydroxide compound, it can be obtained in a wide temperature range, thereby achieving higher fire resistance performance.

That is, the structural water of bentonite is 15
A dehydration reaction occurs at around 0 ° C and has an endothermic effect, but crystal water causes a dehydration reaction at around 700 ° C and has an endothermic effect
It is a defect in fire resistance performance at a temperature of 200 ° C to 600 ° C. However, the hydroxide compound is
Since a dehydration endothermic action occurs at 350 ° C, the defects of bentonite can be compensated.

Further, when a carbonate compound is added, this causes a decomposition and endothermic action at around 800 ° C. to generate carbon dioxide to form a noncombustible gas layer on the surface of the fireproof coating material, and to conduct heat. Since it has the effect of delaying, the fire resistance can be exhibited in a wider temperature range.

[0018]

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples. In Examples and Comparative Examples, white cement is used as the hydraulic cement, calcium bentonite is used as the bentonite, aluminum hydroxide is used as the hydroxide compound, calcium carbonate is used as the carbonate compound, and metasilicic acid is used as the water glass. One kind of sodium,
Obsidian perlite was used as the inorganic lightweight aggregate, alkali-resistant glass fiber was used as the inorganic fiber, and vinyl acetate copolymer-based re-emulsified synthetic resin powder was used as the re-emulsified synthetic resin powder. The blending ratio of these materials was changed for each of the examples and each of the comparative examples, and the mixture obtained by hydro-kneading these materials was applied to a steel plate of 100 × 100 × 1.5 mm with a steel frame of 15 mm.
Apply it thickly and expose it to a furnace heated to 1000 ° C,
The time required for the average temperature of the internal steel frame to reach 350 ° C was determined.

Examples 1 to 5 As shown in Table 1, the amount of bentonite blended was changed within the specified range of the present invention, with the components other than bentonite used in the present invention being set within a suitable range. It was made. 15 mm in any of Examples 1 to 5
In the thick fire resistance test, the fire resistance time exceeds 60 minutes, and it can be seen that sufficient fire resistance performance can be obtained with a thickness much smaller than 20 mm required to achieve the conventional 60 minutes fire resistance time.

[0020]

[Table 1] Examples 6 to 12 These examples mainly examine the influence of each component other than the essential components of the present invention on the change in the compounding amount. As long as hydraulic cement (white cement), bentonite, and hydroxide compound (aluminum hydroxide) are mixed appropriately within the specified range, even if other optional additional components change, the desired fire resistance performance, That is, it is understood that the fire resistance performance of 60 minutes or more can be realized with the coating thickness of 15 mm.

[0021]

[Table 2] Comparative Examples 1 to 3 When bentonite and aluminum hydroxide, which are the essential components of the present invention, are not selectively added, as shown in Table 3,
Even if the content of other components is increased, the desired fire resistance cannot be obtained. From this, it could be confirmed that the bentonite and the hydroxide compound are capable of coexisting and realizing excellent fire resistance performance.

[Table 3] Further, the fire-resistant coating materials obtained from the above-mentioned examples were close to mortar concrete in terms of surface strength, and there was absolutely no risk of scattering, peeling or dropping after the construction. In addition, a white fireproof coating material having excellent durability and weather resistance was obtained, and it was suitable for makeup work such as coloring.

[0022]

INDUSTRIAL APPLICABILITY The refractory coating material of the present invention is decomposed and endothermic when bentonite and a hydroxide compound are heated, and is incombustible by steam gas generated from bentonite, a structured water of a hydroxide compound and crystal water by this reaction The effect of delaying heat conduction during heating of the volatile gas layer is obtained in a wide temperature range due to the difference in reaction temperature of bentonite and the hydroxide compound, thereby realizing higher fire resistance performance.

Therefore, the construction thickness of the fire-resistant coating material can be made thinner, and the spraying work, which conventionally required to be sprayed twice, can be completed once, shortening the construction period, improving work efficiency, and working process. It is possible to simplify the work and reduce the work labor.

When water glass, re-emulsified synthetic resin powder, or hydraulic cement is added, the surface strength of mortar concrete is close to that of mortar concrete, so there is no risk of scattering, peeling, or falling off after construction. At all, there is no need to reinforce the surface strength with a cement filler or the like in the finishing work in the pillar portion. For this reason, the plastering work process such as the cement filler can be omitted, so that the work period can be further shortened, the work efficiency can be improved, the work process can be simplified, and the work labor can be reduced. Also, in terms of makeup, durability,
Since it is a white fireproof coating material with excellent weather resistance, it is also suitable for makeup work such as coloring.

Claims (6)

[Claims] 1. To 100 parts by weight of hydraulic cement,
Bentonite 5 to 500 parts by weight, hydroxide compound 20 to 8
A refractory coating material comprising 100 parts by weight of the composition. 2. A carbonate compound is added to the hydraulic cement 100.
20-800 weight part is included with respect to weight part, The fireproof coating material of Claim 1 characterized by the above-mentioned. 3. The fire resistant coating material according to claim 1, wherein water glass is contained in an amount of 5 to 300 parts by weight with respect to 100 parts by weight of hydraulic cement. 4. An inorganic lightweight aggregate is used as a hydraulic cement 10.
The fireproof coating material according to any one of claims 1 to 3, comprising 5 to 500 parts by weight relative to 0 parts by weight. 5. The fire resistant coating material according to claim 1, wherein the inorganic fiber is contained in an amount of 1 to 50 parts by weight with respect to 100 parts by weight of hydraulic cement. 6. The fire resistant coating material according to claim 1, wherein the re-emulsified synthetic resin powder is contained in an amount of 1 to 300 parts by weight with respect to 100 parts by weight of the hydraulic cement. .