Background of the Invention

1. Field of the Invention

5 The present invention relates to a

fire-extinguishing agent composition which is used for

extinguishing various kinds of fires, and more

particularly to a fire-extinguishing agent composition

which can firstly extinguish the fire by generating foam

^■ 0 which isolates the fire from an oxygen of an air, and can

secondarily extinguish the fire by an incombustible

liquified gas, which is contained in foam and is come out

therefrom when the foams bursts, thereby improving the

fire extinguishing effect. The fire-extinguishing agent

15 composition of the present invention is made by filling a

predetermined amount of an aqueous foaming

fire-extinguishing agent, which is dissolved in water in

a predetermined volume percent, into a pressure vessel

together with the incombustible liquified gas in a

predetermined weight ratio in such a manner that the

incombustible liquified gas can be contained in foam. As

is well known, the aqueous foam fire-extinguishing agent

isolates the fire from the oxygen of the air by using

foam, thereby extinguishing various fires.

2. Prior Arts

Generally, a fire-extinguishing agent is classified

into a foam fire-extinguishing agent, a powder

fire-extinguishing agent such as an ammonium dihydrogen

phosphate, and a halogenated alkane-based volatile

liquid fire-extinguishing agent.

The foam fire-extinguishing agent, which

extinguishes the fire by using foam isolating the fire

from the oxygen of the air or by using a cooling effect

of water, is divided into a chemical foam

fire-extinguishing agent and a mechanical foam

fire-extinguishing agent. In the chemical foam

fire-extinguishing agent, foam is generated from

fire-extinguishing agent by a vapor produced by a

chemical reaction. However, though the chemical foam

fire-extinguishing agent can effectively extinguish the

fire, the agent contained in the chemical foam

fire-extinguishing agent is frozen at the temperature

about five degrees below zero, so the chemical foam

fire-extinguishing agent is not proper to use in the

winter season. In addition, in the mechanical foam

fire-extinguishing agent, a stock solution of the foam

fire-extinguishing agent is dissolved in a large amount

of water, and is mixed with the air by a foaming device,

thereby generating foam. Accordingly, in order to use the

mechanical foam fire-extinguishing agent, not only is

required a foam generator including a mixing device and a

pressure device, but also a large amount of water is

required, so the mechanical foam fire-extinguishing

agent is not proper to widely use under the limited

conditions.

In addition, the powder fire-extinguishing

agent(such as an ammonium dihydrogen phosphate, a sodium

bicarbonate, and a calcium bicarbonate) produces an

ammonia, a carbonic gas, and water while it is being

decomposed by a heat. The ammonia and the carbonic gas

dilute the density of the oxygen in the air or restraint

the supply of the oxygen, and water exerts an cooling

effect on the fire, thereby extinguishing the fire. At

this time, an anhydride of the powder fire-extinguishing

agent is generally melted on the surfaces of

combustibles, thereby forming a film thereto. The film

further restraints the air from contacting with the fire

so that the fire-extinguishing effect is improved.

Accordingly, the powder fire-extinguishing agent having

the ammonium dihydrogen phosphate as a main component is

widely used in the various kinds of fires. However,

since the powder agent has an absorptive property, the

agent of the powder fire-extinguishing agent can be

solidified or deteriorated when it is preserved for a

long time. Further, the powder fire-extinguishing agent

has a large volume, so a volume of a fire-extinguisher is

become larger. Furthermore, the combustibles uncleanly

remain when the fire has been extinguished. Accordingly,

it is not proper to use the powder fire-extinguishing

agent when an expensive equipment or goods are burning.

In addition, a fire-extinguishing agent including a

halogenated alkane, such as a halon 1301 (CF3, Br) and

halon 1211 (CF ₂ ,ClBr) or compounds thereof, is decomposed

by a flame so that it prevents a continuous combustion

reaction of materials, and thereby effectively and

cleanly extinguishing the fire. However, when it is

applied to a well- ventilated place or an open place, the

fire-extinguishing agent should has a sufficient density

so as to extinguish the fire. For this reason, a large

amount of the fire-extinguishing agent, which is more

expensive than the powder fire-extinguishing agent, is

required to extinguish the fire so that the cost is

increased. In addition, since it has a high volatility,

the halogenated alkane-based volatile liquid

fire-extinguishing agent is ineffective than the powder

fire-extinguishing agent when a conflagration occurs.

Further, since the halon is stable, the halogenated

alkane-based volatile liquid fire-extinguishing agent is

slowly decomposed in the air, so it does not rapidly

extinguish the fire. Furthermore, since the halogenated

alkane-based volatile liquid fire-extinguishing agent

destroys an ozone layer in the stratosphere, the

halogenated alkane-based volatile liquid

fire-extinguishing agent may impose the green house

effect on the earth.

Summary of the Invention

The present invention has been made to overcome the

above described problems of the prior arts, and

accordingly it is an object of the present invention to

provide a fire-extinguishing agent which can rapidly

extinguish the fire in its early stage.

To achieve the above object, the present invention

provides a fire-extinguishing agent composition produced

by the method comprising the steps of:

dissolving 6 to 20 volume percent of an aqueous

foaming agent in a water;

injecting the dissolved aqueous foaming agent into

a pressure vessel; and

filling an incombustible liquified gas into the

pressure vessel by applying a pressure, wherein the

fire-extinguishing agent composition discharged from the

pressure vessel has foam containing the incombustible

liquified gas therein.

According to a preferred embodiment of the present

invention, fire-extinguishing foam, which is generated

by the incombustible liquified gas filled in the pressure

vessel, is constantly produced until the incombustible

liquified gas has been completely evaporated.

In addition, the fire-extinguishing agent of the

present invention should not be frozen by an evaporation

heat of the incombustible liquified gas, so the weight or

volume ratio of the aqueous foam fire-extinguishing agent

to the incombustible liquified gas is very important. The

applicant of the present invention has made various

tests, thereby obtaining the improved fire-extinguishing

agent composition.

Description of the Preferred Embodiments

Hereinafter, a preferred embodiment of the present

invention will be described in detail.

A fire-extinguishing agent composition according to

the preferred embodiment of the present invention is

produced by the method comprising the steps of dissolving

6 to 20 volume percent of an aqueous foaming agent in a

water, injecting the dissolved aqueous foaming agent into

a pressure vessel, and filling an incombustible liquified

gas into the pressure vessel by applying a pressure of 30

kg/cm ² .

Light-Water 3%, which is manufactured by 3M company

of U.S.A., is preferably used as an aqueous foaming agent

of the present invention. Light-Water (commonly called

AFFF 3%) consists of 60 weight percent of water, 30

weight percent of 2-2-butoxy ethoxy ethanol, below 5

weight percent of fluoroalkyne surfactant, below 6 weight

percent of synthetic detergent, and below 0.1 weight

percent of methyl benzotriazol.

Light-Water is an aqueous foaming agent, and is

generally used for extinguishing the fire caused by

petroleum products. As is well known, Light-Water is

diluted with water in the density of 3% or 6% when it is

used, and produces foam by means of a pressure pump or a

water supply pump.

In the present invention, the aqueous foaming

agent (AFFF 3%) mixed with water is injected into the

pressure vessel and a incombustible liquified gas (Halon

1301) is filled in the pressure vessel as a foam

generator. In addition, in order to measure the volume

and condition of foam discharged from the pressure

vessel, both the pressure vessel, which has a capacity of

3. 55 1 and is endurable at the pressure of 150 kg/cm

and a measuring instrument which can measure 751 of foam

are used. In this state, the applicant has measured not

only the mixing ratio of the aqueous foaming agent to

water, but also the volume and discharging time of foam,

thereby obtaining numerical value which satisfies the

optimum condition.

The results attained by the various tests are

illustrated in below graphs 1 to 3.

anuHinl nf Irani uflvnl dissolv d in wuUTitl

(graph 1) - foam producing test according to a mixing ratio of an aqueous foaming agent to water (Halon 1301)

(graph 2) - foam producing test according to a variation of an amount of an aqueous foaming agent dissolved in water (Halon 1301)

(graph 3) - foam producing test according to an amount of Halon 1301

As shown in the above graphs, when the ratio of the

aqueous foaming agent to water in a volume is below 6%, a

small amount of foam is produced, and foam discharged out

from the pressure vessel can be frozen caused by the

evaporation of the incombustible liquified gas. In

addition, when the ratio of the aqueous foaming agent to

water in a volume is above 20%, the amount of foam does

not increase. Accordingly, it is preferred to set the

volume ratio of the aqueous foaming agent to water in the

range of 6 to 20%. As shown in graph 1, it is more

preferred to set the volume ratio of the aqueous foaming

agent to water to 11. 5%.

On the other hand, in the fire-extinguishing agent

composition of the present invention, the ratio of the

incombustible liquified gas to the aqueous foaming agent

is preferably in the range of 2.5 : 1 to 1.1 : 1 in a

weight percent.

It is also preferred that the pressure vessel has

pressure of 30 kg/cm .

If the pressure vessel has low pressure, foam may

remain in the pressure vessel. On the contrary, if the

pressure vessel has pressure above 30 kg/cm2, the

pressure vessel discharges gas alone at the last stage.

On the other hand, according to the applicant's

test, the amount of foam is 751 and discharging time is

56 seconds under the following condition (temperature; 12

degree C, a capacity of the pressure vessel; 2.751, the

amount of aqueous foaming agent solution; 1.751, the

amount of the ; 1.31, pressure in the pressure vessel; 30

kg/cm ²⁾ . The discharging time is being shortened as

pressure is being increased.

In addition, though Halon is generally used as a

incombustible liquified gas of the present invention, it

is also possible to use a substitute material as the

incombustible liquified gas instead of Halon. For

example, at least one selected from the group consisting

of 1, 1, 1, 2, 3, 3, 3-heptafluoropropane (commonly called

FM-200), chlorodifluoromethane (commonly called HCFC-22),

2,2-dichloro-l, 1, 1-trifluoroethane (commonly called

H ^C FC-123), and 2-chloro-l, 1, 1,2-tetrafluoroethane

⁽ commonly called HCFC-124), or a mixture thereof mixing

with isopropenyl-1-methylcyclohexene can be used as a

incombustible liquified gas of the present invention.

The applicant of the present invention has made

tests using FM-200 as a incombustible liquified gas.

The results attained by the tests are illustrate _d

in below graphs 4 to 6.

⁽ graph 4) - foam producing test according to a mixing ratio of an aqueous foaming agent to water

⁽ graph 5) - foam producing test according to an amount of FM-200

(graph 6) - foam producing test according to a variation of an amount of an aqueous foaming agent dissolved in water (FM-200)

As is understood from the above graphs, since

FM-200 has a higher latent evaporation heat than Halon

1301 and has low steam pressure, FM-200 does not

sufficiently evaporate, so it cannot effectively expand

foam. However, when the mixing ratio of the aqueous foam

agent to water is 25 volume percent and the amount of

FM-200 is 0.5 kg, 601 of foam is discharged. Though the

amount of discharged foam is less than that of Halon

which discharges 751 of foam, FM-200 is preferable to use

as an incombustible liquified gas because it does not

contaminate the natural environment.

In addition, according to the present invention,

when an incombustible liquified gas having a low

evaporation heat is used as the substitute material, it

is possible to mix carbon dioxide having a high

evaporation heat with the incombustible liquified gas.

Carbon dioxide can be added to the incombustible

liquified gas up to 50 percent with respect to the total

amount of the incombustible liquified gas. In this case,

an 10 weight percent of ethylene glycol is preferably

added to the aqueous foaming agent. Ethylene glycol is a

sort of an anti-freezing solution, so it may prevent foam

from freezing while foam is being discharged from the

pressure vessel.

As described above, the fire-extinguishing agent

composition of the present invention can generate foam,

which produces a film on the combustible material so that

the fire is isolated from the oxygen of the air, thereby

extinguishing the fire. At the same time, the

fire-extinguishing agent composition of the present

invention can dilute the density of the oxygen in the air

by the incombustible liquified gas, which is contained in

foam and is come out therefrom when foam bursts, thereby

improving the fire-extinguishing effect.

While the present invention has been particularly

shown and described with reference to a preferred

embodiment thereof, it will be understood by those

skilled in the art that various changes in form and

detail may be effected therein without departing from the

spirit and scope of the invention as defined by the

appended claims.