JP3320553B2 - Powder extinguishing agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a powder fire extinguishing agent.
More specifically, the present invention relates to a powder fire extinguishing agent obtained by adding melamine pyrophosphate and dipentaerythritol to a conventional powder fire extinguishing agent.

[0002]

2. Description of the Related Art Conventional powder fire extinguishing agents include powder (Na) fire extinguishing agents, powder (K) fire extinguishing agents, and ammonium dihydrogen phosphate containing alkali metal bicarbonate as a main component. A powder (ABC) fire extinguishing agent containing ammonium sulfate as a main component is used. A (wood fire), B (oil fire), C
(Electrical equipment fire) Powder (ABC) fire extinguishing agents which are mainly used for fire and mainly contain ammonium dihydrogen phosphate and / or ammonium sulfate are mainly used.
The powder (Na) fire extinguishing agent and the powder (K) fire extinguishing agent which are mainly composed of alkali metal bicarbonate are used for B and C fires.

[0003] Although these powder fire extinguishing agents have a sufficient fire extinguishing ability, it is necessary to further increase the fire extinguishing ability. Increase fire extinguishing ability against fire A
It is also desired that the powder fire extinguishing agent effective for fires B and C be provided with fire extinguishing ability against fire A and that the range of application of the powder fire extinguishing agents for fires B and C be expanded.

In general, it is considered that conventional powder fire extinguishing agents are effective for B and C fires because alkali metal and / or ammonium groups suppress a chain reaction of combustion. In addition, ammonium dihydrogen phosphate and / or ammonium sulfate is effective for fire A because it radiates chemicals to combustible materials and causes thermal decomposition, and the phosphoric acid and / or sulfuric acid generated at that time acts on cellulose lignin, which is a main component of wood. It is said that the dehydration action is performed to carbonize it to prevent the generation of combustible hydrocarbons, and that the water generated by the dehydration action provides a cooling effect. In particular, ammonium dihydrogen phosphate catalytically promotes the formation of carbon during the combustion of wood, and further decomposes from ammonium dihydrogen phosphate to condensed phosphoric acid and phosphorus pentoxide to form a glassy film on the surface of wood and burn. It is to prevent.

However, a temperature of about 600 ° C. is required for ammonium dihydrogen phosphate to undergo thermal decomposition to reach phosphorus pentoxide. However, since all of the thermal decomposition is an endothermic reaction, combustibles are cooled, Degradation to phosphorus is usually negligible. This suggests that the fire extinguishing ability and the ability to prevent relapse should be improved. That is,
That is, a coating should be formed on the surface of the wood at a relatively low temperature.

The present inventors have proposed a method of forming a coating on the surface of wood at a relatively low temperature as disclosed in Japanese Patent Application No. 5-182408.
As described above, a method of adding melamine pyrophosphate to a conventional powder fire extinguishing agent has been disclosed. However, the strength of the film obtained by this method is not sufficient, and it is required to produce a stronger film.

[0007]

In view of the above, the present inventors have conducted intensive studies in order to obtain a powder fire extinguishing agent having an increased fire extinguishing ability and an expanded range of use of the extinguishing agent.
In a very simple way of adding melamine pyrophosphate and dipentaerythritol to conventional powder fire extinguishing agents,
It has been found that the fire extinguishing ability of fire A can be increased without impairing the fire extinguishing ability of fires B and C, and that the scope of application to fire A can be expanded, and the present invention has been completed.

That is, the present invention relates to a powder fire extinguishing agent containing alkali metal bicarbonate, melamine pyrophosphate and dipentaerythritol, or a powder extinguishing agent containing ammonium dihydrogen phosphate and / or ammonium sulfate, melamine pyrophosphate and dipentaerythritol. .

Hereinafter, the present invention will be described in detail. The alkali metal bicarbonate used in the present invention includes sodium bicarbonate,
Potassium bicarbonate is mainly used. The particle size of the alkali metal bicarbonate, ammonium dihydrogen phosphate and / or ammonium sulfate is usually ground to 177 μm or less. The melamine pyrophosphate used in the present invention is generally commercially available, but the following production method is more preferred. However, it is not limited to these methods.

[0010] One of the production methods is to react melamine in an aqueous slurry state with a mineral acid such as hydrochloric acid, nitric acid or sulfuric acid to produce water-soluble melamic acid, and to react this salt with sodium pyrophosphate. A method of further adding a mineral acid to precipitate melamine pyrophosphate. As another method, a method of dissolving sodium pyrophosphate in water, dispersing melamine in the aqueous solution, and adding a mineral acid such as hydrochloric acid, nitric acid or sulfuric acid to the solution or slurry to react to precipitate melamine pyrophosphate, Etc. are known. From the slurry containing melamine pyrophosphate obtained by these methods, the melamine pyrophosphate obtained by separation by a commonly used separation method and drying by a usual drying method is subjected to a conventional method using a pulverizer.
It is obtained by crushing to 7 μm or less.

In the present invention, the melamine pyrophosphate is added in an amount of 0.1 to 4 with respect to alkali metal bicarbonate or ammonium dihydrogen phosphate and / or ammonium sulfate.
It is preferably 0% by weight, more preferably 1 to 35% by weight, and most preferably 5 to 30% by weight. If the added amount is less than 0.1% by weight, neither increase nor expansion of the fire extinguishing ability is achieved, which is not preferable. On the other hand, if the addition amount exceeds 40% by weight, it is uneconomical and the fluidity of the powder fire extinguishing agent is lowered, which is not preferable.

Although dipentaerythritol used in the present invention may be generally commercially available, it is more preferably produced by the following production method. However, it is not limited to these methods.

That is, it is obtained by condensing 4 mol of formaldehyde and 1 mol of acetaldehyde with an alkali catalyst, and dipentaerythritol is isolated by recrystallization. The obtained crystals of dipentaerythritol are obtained by pulverizing the crystals of dipentaerythritol to 177 μm or less using a conventional pulverizer.

The amount of dipentaerythritol added in the present invention is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, based on melamine pyrophosphate.
However, most preferably, 20 to 30% by weight is suitable. If the added amount is less than 5% by weight, neither increase nor expansion of the fire extinguishing ability is achieved, which is not preferable. On the other hand, if the addition amount exceeds 50% by weight, it is uneconomical and the flowability of the powder fire extinguishing agent decreases, which is not preferable.

However, the present inventors have conducted various experiments and the results and observations thereof have shown that the fire-extinguishing mechanism of the powder fire extinguishing agent to which the melamine pyrophosphate and dipentaerythritol of the present invention are added is based on the melamine pyrophosphate itself added to the main agent. Is heated by the heat of the combustion atmosphere, decomposition occurs, and the generation of ammonia causes an incombustible film formed by excess polyphosphoric acid or the like to cover the combustible material, and carbon generated by carbonization of dipentaerythritol by phosphoric acid. It is presumed that the fire extinguishes quickly and prevents relapse because a strong film is formed.

[0016] Melamine pyrophosphate has the following excellent physical properties as a fire extinguishing agent component. That is, 1) the N and P contents of the fire extinguishing component are high. 2) It is almost insoluble in water and has low hygroscopicity. 3) Thermal decomposition temperature is 320-330
Start foaming at ° C. 4) A film is formed on the surface of wood at a relatively low temperature and quickly.

In addition to the above components, the powdered fire extinguishing agent of the present invention may be used as a fluidizing agent, a water repellent, a stabilizer, and the like, for example, hydrophobic silica, silicone oil, talc, mica, alkaline earth metal salts Usually, one or more of silicates and the like are appropriately added and used. The addition of these components is preferably about 1 to 5% by weight based on the powder fire extinguishing agent. A large amount of addition is not only uneconomical, but also affects the fire extinguishing ability.

As the hydrophobic silica used in the present invention, those commercially available are usually used. However, the production of hydrophobic silica is carried out by the following methods, but is not limited to these production methods. To produce hydrophobic silica, 100 parts by weight of white carbon is put into a mixer, 20 to 40 parts by weight of a silicone resin is added by spraying, and the obtained powder is cured by heating at 130 to 150 ° C. for 3 to 5 hours. Can be

The powder fire extinguishing agent of the present invention can be produced by mixing the main agent, melamine pyrophosphate, dipentaerythritol, a fluidizing agent, a water repellent, and a stabilizer in the above-mentioned mixing ratio. It's a very simple thing to do. Moreover, in the case of powder extinguishing agents for A, B and C fires, the fire extinguishing ability for fire A is increased without impairing the extinguishing ability for fires B and C. In the case of powder extinguishing agents for fires B and C, the same applies. In addition, the scope of application can be extended to fire A without compromising the fire extinguishing ability against fire B and C. In addition, it is a powder fire extinguishing agent which has excellent industrial value and has a remarkably improved quick extinguishing property and relapse prevention ability, and can be manufactured at low cost.

[0020]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the gist of the present invention is not limited thereto. The fire extinguishing test method for Fire A and Fire B is a ministerial ordinance that stipulates the technical standards for fire extinguishers (October 17, 1973
The Ministry of Home Affairs Ordinance No. 28) conducted the survey. Parts and percentages are by weight unless otherwise specified.
Represents

Example 1 A powder fire extinguishing agent 5 was prepared so that 100 parts of sodium bicarbonate having an average particle diameter of 80 μm, 5 parts of melamine pyrophosphate having an average particle diameter of 30 μm, 2 parts of dipentaerythritol and 1 part of hydrophobic silica were used. 0.0 kg was produced. The moisture absorption of the powder fire extinguishing agent was 1.0%. Using this, a fire test of B-5 units was performed. As a result, as shown in Table 1, the fire extinguishing time was 4.6 seconds, the amount of chemical used was 1.2 kg, and
As a result of the fire test of -1 unit, there was no after-flame, no afterglow (wood became red) was observed, and the fire was completely extinguished. Many carbonized coatings were found on the wood surface, and it was confirmed that the wood surface temperature was sufficiently cooled.

Example 2 The same procedure as in Example 1 was carried out except that melamine pyrophosphate was changed to 11 parts and dipentaerythritol was changed to 3 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 3 The procedure of Example 1 was repeated, except that melamine pyrophosphate was changed to 18 parts and dipentaerythritol to 5 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 4 Example 4 was carried out under the same conditions as in Example 1 except that melamine pyrophosphate was changed to 35 parts and dipentaerythritol to 2 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 5 100 parts of ammonium dihydrogen phosphate having an average particle size of 50 μm and 5 parts of melamine pyrophosphate having an average particle size of 30 μm, 2 parts of dipentaerythritol and 2 parts of silica were subjected to a water-repellent treatment with 1 part of silicone oil. Was used to produce 5.0 kg of a powder fire extinguishing agent so as to have this blending ratio. The moisture absorption of the powder fire extinguishing agent was 0.1%. As a result of performing a B-5 unit fire test using this, the fire extinguishing time was 4.4 seconds, and the amount of chemical used was 1.5 kg. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

The water repellent treatment of the silica was performed as follows. Silica was put into a mixer, silicon oil was added by spraying, and the obtained powder was obtained by heating at 140 ° C. for 4 hours.

Example 6 Example 6 was carried out under the same conditions as in Example 6, except that melamine pyrophosphate was changed to 11 parts and dipentaerythritol was changed to 3 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 7 Example 7 was carried out under the same conditions as in Example 6 except that melamine pyrophosphate was changed to 18 parts and dipentaerythritol to 5 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 8 Example 6 was carried out under the same conditions as in Example 6, except that melamine pyrophosphate was changed to 35 parts and dipentaerythritol to 2 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 9 55 parts of ammonium dihydrogen phosphate, 45 parts of ammonium sulfate
Parts and 2 parts of silica were subjected to a water-repellent treatment with 1 part of silicon-oil, and 5.0 kg of a powder fire extinguishing agent was manufactured so as to have this mixing ratio. The moisture absorption of the powder fire extinguishing agent was 0.6%. A fire test of B-5 units was carried out using this, and as a result, the fire extinguishing time was 4.8 seconds, and the amount of drug used was 1.6 kg. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 10 Example 9 was carried out under the same conditions as in Example 9 except that melamine pyrophosphate was changed to 11 parts and dipentaerythritol to 3 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 11 Example 9 was carried out under the same conditions as in Example 9 except that melamine pyrophosphate was changed to 18 parts and dipentaerythritol to 5 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

Example 12 Example 9 was carried out under the same conditions as in Example 9 except that melamine pyrophosphate was changed to 35 parts and dipentaerythritol to 2 parts. Table 1 shows the moisture absorption rate, fire extinguishing time in B-5 units, and amount of the powder fire extinguishing agent used. Similarly, the results of the fire test in A-1 units were the same as in Example 1 as shown in Table 1.

[0034]

[Table 1]

COMPARATIVE EXAMPLE 1 5.0 kg of a powder fire extinguishing agent was prepared so that the mixing ratio was 100 parts of sodium bicarbonate and 1 part of hydrophobic silica. As a result of conducting a fire test of B-5 units using this, as shown in Table 2, the fire extinguishing time was 6.2 seconds and the amount of chemicals used was 2.6 kg. Met.

Comparative Example 2 Using 100 parts of ammonium dihydrogen phosphate and 2 parts of silica treated with 1 part of silicone oil for water repellency, 5.0 kg of a powder fire extinguishing agent was manufactured so as to have this mixing ratio.
As a result of conducting a fire test of B-5 unit using this, as shown in Table 2, the fire extinguishing time was 5.8 seconds and the amount of chemical used was 2.2.
In the same way, the result of the fire test in A-2 unit was that the fire was completely extinguished and did not relapse even after 2 minutes. There was no afterflame after the fire was extinguished, but some afterglow was seen, and smoldering continued for 2 minutes, but after 2 minutes the flame rose and did not burn.

Comparative Example 3 55 parts of ammonium dihydrogen phosphate and 45 parts of ammonium sulfate
Parts and 2 parts of silica were subjected to a water-repellent treatment with 1 part of silicon-oil, and 5.0 kg of a powder fire extinguishing agent was manufactured so as to have this mixing ratio. As a result of performing a fire test of B-5 units using this, as shown in Table 2, the fire extinguishing time was 6.4 seconds and the amount of chemicals used was 2.8 kg.
The results of the two-unit fire test showed that the fire was completely extinguished, but relapsed after one minute.

Comparative Example 4 100 parts of sodium bicarbonate having an average particle size of 80 μm, 11 parts of melamine pyrophosphate having an average particle size of 30 μm and hydrophobic silica 1
5.0 kg of a mixture was produced so that the mixing ratio was 5 parts by weight. The moisture absorption of this powder fire extinguishing agent was 1.2%. Using the mixture, a fire test of B-5 units was performed. As a result, as shown in Table 2, the fire extinguishing time was 5.0 seconds, the amount of chemicals used was 2.0 kg, and the fire test of A-1 unit was also performed. As a result, there was no afterflame, no afterglow (wood became red) was observed, and the fire was completely extinguished. Many coatings were found on the wood surface, and it was confirmed that the wood surface temperature was sufficiently cooled.

COMPARATIVE EXAMPLE 5 100 parts of ammonium dihydrogen phosphate having an average particle diameter of 50 μm, 18 parts of melamine pyrophosphate having an average particle diameter of 30 μm, and 2 parts of silica treated with 1 part of silicone oil for water repellency were used. 5.0 kg of powder fire extinguishing agent so that it becomes the ratio
Was manufactured. The moisture absorption of this powder fire extinguishing agent was 0.2%. A fire test of B-5 units was carried out using this, and as a result, as shown in Table 2, the fire extinguishing time was 4.7 seconds and the amount of chemical used was 1.7 kg. Similarly, the result of the fire test of the A-2 unit showed that there was no afterflame, no afterglow was observed, the fire was completely extinguished, and the fire did not recur after 2 minutes. Many coatings were found on the wood surface, and it was confirmed that the wood surface temperature was sufficiently cooled.

Comparative Example 6 55 parts of ammonium dihydrogen phosphate having an average particle diameter of 50 μm, 45 parts of ammonium sulfate having an average particle diameter of 60 μm, and 18 parts of melamine pyrophosphate having an average particle diameter of 30 μm and 2 parts of silica were repelled with 1 part of silicone oil. Using the treated product, 5.0 kg of a powder fire extinguishing agent was manufactured so as to have this mixing ratio. The moisture absorption of this powder fire extinguishing agent was 0.6%. A fire test of B-5 units was performed using this, and Table 2 shows the results.
As shown in the figure, the fire extinguishing time was 5.3 seconds, and the amount of drug used was 1.9.
In the same way, the result of the fire test in the unit of A-1 was that there was no after-flame, no afterglow was observed, and the fire was completely extinguished. Many coatings were found on the wood surface, and it was confirmed that the wood surface temperature was sufficiently cooled.

[0041]

[Table 2]

The fire tests of Examples and Comparative Examples were performed as follows. A-1 Unit fire test: Cedar square wood (length 3c)
mx 3.5cm wide x 70cm long)
90 units are piled up in a girder shape with a unit of gasoline, and gasoline 1.5
The fire was extinguished using a fire extinguisher containing 3.0 kg of powder extinguishing agent after 3 minutes, and the state of fire extinguishing was measured.

A-2 Unit fire test: Sixty six, six, five and five cedar square lumbers (3 cm × 3.5 cm × 90 cm in length) are stacked on a combustion rack in a cross-girder form. ,
It ignites using 3.0 L of gasoline, extinguishes the fire after 3 minutes, and measures the state of fire extinguishing.

B-5 unit fire test: 12 oil was poured into an iron oil pan (100 cm long × 100 cm wide × 30 cm deep).
cm of gasoline, ignited by putting gasoline at a depth of 3 cm on top of it, and fired with a fire extinguisher with 3.0 kg of powder fire extinguisher after 1 minute. It measures the amount used.

Measurement of moisture absorption of fire extinguishing agent: About 10 g of sample
Finely weighed on a 0φ Petri dish to make the thickness of the sample uniform,
After standing for 48 hours in a thermo-hygrostat at a temperature of 30 ° C. and a relative humidity of 60%, take out the petri dish and weigh it. Weigh and the rate of change in weight during this period is defined as the moisture absorption rate.

[0046]

According to the present invention, it is an object of the present invention to provide a powder fire-extinguishing agent which has not been achieved by the prior art, has a remarkably increased fire-extinguishing ability, and further prevents re-ignition. That is, by adding melamine pyrophosphate and dipentaerythritol to the main agents for fires A, B, and C, the fire extinguishing ability against fires A can be increased.
The fire extinguishing ability is not impaired at all, and the fire can be completely extinguished to prevent re-ignition. The fire extinguishing ability of fire A is provided by adding melamine pyrophosphate and dipentaerythritol to the main agents for fire B and C.

Continuation of front page (56) References JP-A-57-9468 (JP, A) JP-A-61-5856 (JP, A) JP-A-58-53964 (JP, A) JP-A-54-53156 (JP, A) JP-A-7-187626 (JP, A) JP-B-40-28594 (JP, B1) JP-T-61-502763 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) A62D 1/00 C09K 21/00

Claims (4)

(57) [Claims] 1. A powder fire extinguishing agent comprising an alkali metal bicarbonate, melamine pyrophosphate and dipentaerythritol. 2. A fire-extinguishing powder comprising ammonium dihydrogen phosphate and / or ammonium sulfate, melamine pyrophosphate and dipentaerythritol. 3. The method according to claim 1, wherein the melamine pyrophosphate is 0.1 to 40% by weight based on the alkali metal bicarbonate and the dipentaerythritol is 5 to 50% by weight based on the melamine pyrophosphate. Powder extinguishing agent. 4. Melamine pyrophosphate is added in an amount of 0.1 to ammonium dihydrogen phosphate and / or ammonium sulfate.
3 to 40% by weight, and dipentaerythritol is 5 to 50% by weight based on melamine pyrophosphate.
Powder extinguishing agent as described.