Sticky high water content gels for extinguishers

Sticky high water content gelled fire extinguisher compositions hold the antage of providing a high water content, slightly viscous (sticky) gel with flow properties similar to water. The ability of this material to stick to burning surfaces is what sets it apart from water extinguishers. Not only are fires extinguished, but also surfaces are cooled by the sticky gel as the water evaporates. The basic gelled fire extinguisher composition is comprised of about 88 weight percent water and about 12 weight percent of a 7 nanometer particle size silicon dioxide gellant. The silicon dioxide gellant is available as EH5 tradename by Cabot for this silicon dioxide gellant. Other ingredients such as dispersants, wetting agents and flame retardants can be used as additives in combination with the gelling agent. The actual gel system is inexpensive, made from readily available ingredients and easily prepared.

DEDICATORY CLAUSE 
The invention described herein may be manufactured, used, and licensed by 
or for the Government for governmental purposes without the payment to us 
of any royalties thereon. 
BACKGROUND OF THE INVENTION 
The Army has sticky napalm gasoline/gellant/detergent fuel for 
flame-throwers and fire bombs. The "napalm gasoline gel" functions as fire 
setting/spreading. A similar concept can be used (military/civilian use 
technology) for improved extinguisher material compositions based on a 
high water content coolant, sticky gellant, tri-sodium phosphate 
dispersant, wetting agent, flame retardant composition. This fire 
retardant material can be sprayed and would stick to burning or flammable 
surfaces or personnel and extinguish or retard fire spreading. This 
material would also be inexpensive, non-toxic, readily available and 
easily prepared. 
A commonly assigned U.S. Pat. No. 4,008,170, titled: "Dry Water", was 
issued to Barry D. Allan on Feb. 15, 1977. This patent discloses a 
submicroscopic particulate silica having a particle size range from about 
15-20 m.mu. that is prepared in a hot gaseous environment at about 
1100.degree. C. by the vapor phase hydrolysis of a silicon compound. This 
product is reacted with liquid water in a ratio in weight percent of about 
1 part water to about water to about 9 parts water to 1 part of the 
particulate silica to yield a powdered product which remains flowable over 
a wide temperature, even when cooled to an extremely low temperature of 
-196.degree. C. The adsorbed water is liberated on heating the powdered 
product. The powdered product with adsorbed water, up to 90 weight 
percent, has utility as a coolant by liberating water on heating. The 
powdered product is useful as moisture source for miscellaneous purposes 
over a wide temperature range. The described product, which is known as 
"dry water", remains flowable over a wide temperature; hence, the term 
"dry water" is fitting to the properties of the patented product. 
An object of this invention is to provide a sticky high water content gel 
for extinguishers. 
A further object of this invention is to provide a sticky high water 
content gel fire retardant material which can be sprayed and would stick 
to burning or flammable surfaces or personnel and extinguish or retard 
fire spreading. 
Still another object of this invention is to provide a sticky gel system 
which can be made from inexpensive and readily available non-toxic 
materials and which is easily prepared. 
SUMMARY OF THE INVENTION 
Sticky high water content gel for extinguishment of fires and retards 
spreading. The concept is similar to the "napalm gasoline gel" used in 
fire bombs and flame throwers, except that the usage is completely 
opposite, e.g. extinguishment rather than fire setting/spreading. This 
gellant concept is also used in gelling rocket fuels and oxidizers by the 
Army. The water gel contains a small amount of sodium triphosphate 
(dispersant/wetting agent/flame retardant). Other water soluble inorganic 
flame retardants such as sodium bromides can also be added. All of the 
above ingredients are inexpensive and commercially available. This gel 
composition when sprayed onto burning wood or similar surfaces, 
spreads/sticks to it, and extinguishes the flame rapidly by 
smothering/cooling the burning surface. As the water evaporates and 
temperature rises in the gel-coating on the burning surface, the gellant 
and retardant concentration rises and maintains gel viscosity/flame 
retarding effectiveness. 
The basic gelled fire extinguisher composition is comprised of about 88 
weight percent water and about 12 weight percent of a 7 nanometer particle 
size silicon dioxide gellant. The silicon dioxide gellant is available as 
EH5 tradename by Cabot for this silicon dioxide gellant. Other ingredients 
such as dispersants, wetting agents and flame retardants can be used as 
additives in combination with the gelling agent. The actual gel system is 
inexpensive, made from readily available ingredients and easily prepared. 
DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
Baseline compositions tested in proof-of-principle tests contained 88% 
available water from the reaction product "dry water" of about 100 parts 
and 12% of a 7 nm ("EH5" tradename by Cabot) silicon dioxide gellant. This 
composition with this particular gellant provided a material with the 
highest percentage of water to give the optimum flow properties while 
still containing enough gellant to provide high enough viscosity to remain 
sticky. This material was tested in a modified caulking-gun tube. This 
material was pressurized with 25 psi air. A 45.degree. vortex was cut in 
the tip of the tube to simulate a nozzle. This material was tested on 
kerosene soaked sheets of cardboard. The fires were successfully 
extinguished and the cardboard was also completely cooled off.

It is to be understood, therefore, that while the present invention has 
been described by means of specific examples, it should not be limited 
thereto, for obvious variations and modifications may occur to those 
skilled in the art and such variations and modifications may be adhered to 
without departing from the spirit of the invention or the scope of the 
applied claims.