JPH0825808B2 - Fireproof coating material with hydrogen carbonate compound - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention has improved fire resistance.

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 dominated most of the fire-resistant coating materials produced 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 fireproof coating materials is that the fireproof coating material has a thickness of 20 mm in the 1-hour fireproof test in the column portion and 30 mm in the 2-hour fireproof test.
The time fire resistance test is about 40 mm. That is, the thickness that satisfies the 3-hour fire resistance test is about 40 mm. With this thickness, it is not possible to spray to a predetermined thickness at one time, and since it has to be sprayed twice, work efficiency in spraying work, non-rock wool type fireproof coating material The refractory principle of is the endothermic action at the time of heating by the combined action of carbonate compound and hydroxide compound,
It utilizes the delay of heat conduction due to the formation of a nonflammable gas layer on the surface of the fireproof coating material of carbon dioxide gas and water vapor gas. However, the hydroxide compounds and carbonate compounds, which are the main components of the fire-resistant principle, depend on their types and proportions, but the time from when the hydroxide compound undergoes the decomposition endothermic reaction until when the carbonate compound undergoes the decomposition endothermic reaction. It has a drawback that the effect of endothermic action is not obtained because the temperature difference is too wide.

When aluminum hydroxide and calcium carbonate are given as examples of commonly used hydroxide compounds and carbonate compounds, aluminum hydroxide undergoes an endothermic decomposition reaction at about 250 ° C., but calcium carbonate decomposes and endotherms up to about 800 ° C. Since it does not cause a reaction, it is unfavorable on the principle of fire resistance at a temperature of about 500 ° C to 800 ° C. Further, although the simple noncombustible gas such as carbon dioxide gas and steam gas has the test result that the fireproof effect is lower than the mixed noncombustible gas,
Since there is a difference in reaction temperature between aluminum hydroxide and calcium carbonate, a non-combustible gas mixed with carbon dioxide gas and water vapor gas is hard to be generated, and effective fire resistance performance is hard to be obtained.

[0007]

The refractory coating material of the present invention contains a carbonate compound and a hydroxide compound, which are disadvantages of the present non-asbestos and non-rock wool type refractory coating materials by adding a hydrogen carbonate compound. The non-combustible gas mixture of carbon dioxide gas and steam gas, which was difficult to generate due to the temperature difference that causes the decomposition endothermic reaction, is efficiently and reliably generated, and higher fire resistance performance is realized. It is 70% by weight for 100 parts by weight of binder made of hydraulic cement and / or water glass.
5 to 600 parts by weight of a hydrogen carbonate compound which decomposes within 0 ° C.,
The gist is to have a composition of 5 to 400 parts by weight of inorganic lightweight aggregate. Furthermore, 20 to 800 parts by weight and / or 800 parts by weight of a carbonate compound that decomposes within 1000 ° C.
It is desirable to contain 20 to 800 parts by weight of a hydroxide compound that decomposes within a temperature of 0 ° C. Furthermore, 1 to 1 of the re-emulsified synthetic resin powder
Including 200 parts by weight, 2 to 50 inorganic fibers
It is desirable to include parts by weight.

(Description of Specific Structure) In the present invention, either or both of hydraulic cement and water glass are used as a binder, but preferably both are used, and the compounding ratio thereof is hydraulic cement. The amount of water glass is 5 to 200 parts by weight with respect to 100 parts by weight.

Specific examples of the hydraulic cement include Portland cement, alumina cement, silica cement, blast furnace cement, fly ash cement and sulfuric acid 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. Examples of water glass include sodium metasilicate 1 and 2 as specific examples.
Those which belong to the species and are in the form of powder or granules can be mentioned. Water glass, like hydraulic cement, effectively acts to improve the adhesion strength of the fire-resistant coating material to the steel frame at high temperatures, the mechanical strength of the fire-resistant coating material, and the surface strength of the fire-resistant coating material. To do.

The hydrogen carbonate compound that decomposes within 700 ° C., which is a characteristic component of the present invention, is, for example, sodium hydrogen carbonate (NaHCO ₃ ) or calcium hydrogen carbonate ((Ca (HCO ₃ ) ₂ ). ) Etc.
This achieves the endothermic effect when the hydrogen carbonate compound is decomposed by heating during refractory and the effect of delaying the heat conduction due to the formation of the steam gas and carbon dioxide layer, and the effect of improving the surface strength of the refractory coating material. . The blending ratio is 5 to 600 parts by weight, preferably 50 to 300 parts by weight, based on 100 parts by weight of the binder. If the blending ratio of the hydrogen carbonate compound is below the lower limit, decomposition endothermic action due to heating at the time of fire resistance and the effect of delaying heat conduction due to formation of water vapor gas and carbon dioxide layer cannot be expected, and above the upper limit the fire resistance Further effects of decomposition endothermic action due to heating at the time and delay of heat conduction due to formation of steam gas and carbon dioxide layer cannot be obtained.

The inorganic lightweight aggregates include obsidian perlite and pearlite perlite as specific examples, and unburned vermiculite as a more specific example. When unburned vermiculite is used, it is desirable to also use inorganic fibers for the purpose of preventing the refractory coating material from falling off and peeling because the refractory coating material expands due to heating during fireproofing. 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 blending ratio is 5 to 400 parts by weight, preferably 30 to 150 parts by weight, based on 100 parts by weight of the binder. If the compounding 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 decreases. It will be.

Specific examples of the carbonate compound which decomposes within 1000 ° C. include calcium carbonate (CaCO ₃ ) and magnesium carbonate (MgCO ₃ ). 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 compounding ratio is 20 to 800 parts by weight with respect to 100 parts by weight of the binder, and preferably 100 parts by weight.
~ 400 parts by weight.

A hydroxide compound which decomposes within 800 ° C. is, for example, aluminum hydroxide ((Al (OH)
₃ )), gibbsite, etc. 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.
In addition, the mixing ratio is 100 parts by weight of the binder,
20 to 800 parts by weight, preferably 100 to 40
0 parts by weight.

Further, as the re-emulsified synthetic resin powder, a preferred specific example is vinyl acetate copolymer-based re-emulsified synthetic resin powder. The re-emulsified synthetic resin powder can be expected to improve the adhesive strength of the refractory coating to the steel frame at room temperature and the surface strength of the refractory coating. When the re-emulsified synthetic resin powder is added, the mixing ratio is 1 to 100 parts by weight of the binder.
The amount is 100 parts by weight, preferably 5 to 20 parts by weight. If the blending ratio of the re-emulsified synthetic resin powder is less than or equal to the lower limit value, improvement in the adhesive strength of the fire-resistant coating material to the steel frame cannot be expected,
When it is at least the upper limit, the adhesive strength of the fire-resistant coating material to the steel frame will not be improved and the surface strength of the fire-resistant coating material will not be further improved.

Specific examples of the inorganic fibers include alkali resistant glass fibers and ceramic fibers. 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. When the inorganic fiber is added, its compounding ratio is 2 to 50 parts by weight, preferably 3 to 10 parts by weight, based on 100 parts by weight of the binder. If the blending ratio is less than the lower limit, it cannot be expected to prevent the fire-resistant coating material from falling off or peeling off during fire, and if it is more than the upper limit, the effect of preventing further dropping or peeling cannot be obtained. .

[0016]

The high fire resistance in the composition of the fire-resistant coating material of the present invention is due to the decomposition and endothermic action of the hydrogen carbonate compound, the carbonate compound and the hydroxide compound during heating, and the incombustibility due to the carbon dioxide gas and the steam gas generated from these compounds. It is considered to be obtained by the action of delaying the thermal conductivity due to the formation of the volatile gas layer. In particular, by adding a hydrogen carbonate compound, it was difficult to generate carbon dioxide due to the temperature difference that caused the decomposition endothermic reaction between the carbonate compound and the hydroxide compound, which was a drawback of the current non-asbestos and non-rock wool type fireproof coating materials. It is considered that the non-combustible gas, which is a mixture of gas and steam gas, is efficiently and reliably generated, and that it contributes greatly to the realization of higher fire resistance performance.

Of the fireproof coating materials of the present invention, the fireproof mechanism of the fireproof coating materials containing a carbonate compound and a hydroxide compound will be described below in a form conforming to the fireproof test temperature.

In the event of a fire, the hydroxide compound first undergoes a decomposition and endothermic reaction at about 250 ° C., and most of the steam gas proceeds to the surface layer of the fire-resistant coating material, forming a nonflammable gas layer. However, a certain amount of steam gas will proceed inside the refractory coating material. This accumulates between the layers of the steel frame surface and the refractory coating material and hinders the temperature rise of the steel frame.

When the surface temperature of the refractory coating material reaches about 350 ° C., the hydrogen carbonate compound gradually decomposes and undergoes an endothermic reaction to generate carbon dioxide gas and water vapor gas. Although this is a mixed non-combustible gas, most of the non-combustible gas forms a non-combustible gas layer on the heated surface of the refractory coating as it exits the refractory coating. However, the steam gas in the non-combustible gas to some extent progresses inside the refractory coating material like the steam gas due to the hydroxide compound and accumulates between the steel surface and the refractory coating material to prevent the temperature rise of the steel frame. .

When the surface temperature of the refractory coating material reaches about 800 ° C., the carbonate compound gradually decomposes and undergoes an endothermic reaction to form carbon dioxide gas. This carbon dioxide gas forms a non-combustible gas layer on the heated surface of the refractory coating as it passes through the refractory coating, delays the heat conduction of the refractory coating and prevents the temperature rise of the steel frame.

It is speculated that the above phenomenon progresses from the heated surface of the refractory coating material toward the inside with the passage of time.

[0022]

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, sodium metasilicate is used as water glass, sodium hydrogen carbonate is used as the hydrogen carbonate compound, aluminum hydroxide is used as the hydroxide compound, and carbonate compound is used as the carbonate compound. Was calcium carbonate, obsidian perlite was used as the inorganic lightweight aggregate, re-emulsified emulsion was used as the re-emulsified synthetic resin powder, and alkali-resistant glass fiber was used as the inorganic fiber. The blending ratio of each of the examples,
And, for each comparative example, a mixture obtained by hydro-kneading these materials was used, and a mixture of 100 × 100 × 1.5 m assuming a steel frame was used.
A 15 mm thick iron plate was applied to the m steel plate and exposed to a furnace heated to 1000 ° C., and the time until the average temperature of the internal steel frame reached 350 ° C. was obtained.

Examples 1 to 3 As shown in Table 1, the blending ratio of white cement, water glass, obsidian perlite, alkali resistant glass fiber, and re-emulsified emulsion was kept constant, and the blending ratio of sodium hydrogen carbonate was lower than the lower limit value. The amount is changed to the upper limit, and appropriate amounts of aluminum hydroxide and calcium carbonate are added for each example. In all of Examples 1 to 3, the 15 mm thick fire resistance time is longer than 60 minutes, and it is possible to obtain sufficient fire resistance performance at a thickness much lower than 20 mm required to achieve the conventional 60 minutes fire resistance time. I understand. Further, in Example 3, sodium hydrogencarbonate is used alone without adding aluminum hydroxide and calcium carbonate, and it can be seen that even at this time, sufficiently high fire resistance performance is obtained.

[0024]

[Table 1] Examples 4, 5, 6 and 7 As shown in Table 2, Examples 4 and 5 are configured such that each additive element has a compounding ratio considered to be its optimum value. Although the total content of sodium hydrogen carbonate, aluminum hydroxide and calcium carbonate was smaller than that in Example 3, the 15 mm thick fire resistance time exceeded this and it can be seen that there is a synergistic action of each element. Further, Examples 6 and 7 are aluminum hydroxide, calcium carbonate,
Although the alkali resistant glass fiber and the re-emulsified synthetic resin powder are not added, the fire resistance performance of more than 60 minutes can be obtained even in this case.

[0025]

[Table 2] Examples 8 to 12 In Examples 8 and 9, as shown in Table 3, the binder is only white cement and only water glass. In these cases, the fire resistance time of 15 mm thickness is significantly longer than 60 minutes, and if the other components are added in appropriate amounts, even if only white cement or only water glass is used as the binder, sufficient fire resistance performance is obtained. You can get Furthermore, in Examples 10 to 12, as shown in Table 3, white cement, water glass, sodium hydrogen carbonate, obsidian perlite, alkali resistant glass fiber, and re-emulsified emulsion were mixed at a constant compounding ratio, and aluminum hydroxide and carbonate were used. The calcium content was changed within the range of 200 parts by weight in total. In all of Examples 8 to 12, the 15 mm-thick fire resistance time was longer than 60 minutes, and it can be seen that the fire resistance performance is sufficient.

[0026]

[Table 3] Comparative Examples 1 and 2 As shown in Table 4, sodium hydrogencarbonate was not added, and those below the lower limit were added. Despite the addition of aluminum hydroxide and calcium carbonate, the 15 mm thick fire resistance time did not reach 60 minutes.

[0027]

[Table 4] 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.

[0028]

The remarkable point of the present invention is that by adding a hydrogen carbonate compound, decomposition of the carbonate compound and the hydroxide compound, which is a drawback of the present non-asbestos and non-rock wool type fireproof coating materials, is caused. It is to efficiently and reliably generate a non-combustible gas of a mixture of carbon dioxide gas and water vapor gas, which is difficult to generate due to a temperature difference causing an endothermic reaction, and realize higher fire resistance performance.

Further, in the fireproof coating material to which the carbonate compound and the hydroxide compound are added, the hydrogen carbonate compound reacts in the middle of the temperature difference causing the decomposition and endothermic reaction, so that the decomposition grade thermal reaction and nonflammability The formation of the gas layer occurs in a wide temperature range, and higher fire resistance performance can be realized.

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 only once, shortening the construction period, improving the work efficiency, and the work process. It is possible to simplify the work and reduce the work labor.

Further, when water glass, re-emulsified synthetic resin powder, and hydraulic cement are added, these effects produce a surface strength 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 (4)

[Claims] 1. A binder composed of a hydrogen carbonate compound which decomposes within 700 ° C., an inorganic lightweight aggregate, hydraulic cement and / or water glass as an active ingredient, and the compounding ratio thereof is 100% by weight of the binder. A fire resistant coating material having a composition of 5 to 600 parts by weight of a hydrogen compound and 5 to 400 parts by weight of an inorganic lightweight aggregate. 2. 1000 parts by weight per 100 parts by weight of binder
20 to 800 parts by weight of a carbonate compound that decomposes within ℃,
And / or 2 hydroxyl compounds that decompose within 800 ° C.
The fire resistant coating material according to claim 1, wherein the fire resistant coating material contains 0 to 800 parts by weight. 3. The fire-resistant coating material according to claim 1, which contains 1 to 100 parts by weight of the re-emulsified synthetic resin powder with respect to 100 parts by weight of the binder. 4. The fire-resistant coating material according to claim 1, wherein the inorganic fiber is contained in an amount of 2 to 50 parts by weight with respect to 100 parts by weight of the binder.