001 The present invention relates to a white smoke composition, which costs more economical to manufacture and
environment friendly which can be used for signalling or screening purposes in military exercises or in some other
smoke requiring activities. Various devices and compositions are presently used for such purposes are not
economical to produce and not even non-toxic & environment friendly. The present invention is related to generally
cool-burning, environment friendly, and non-corrosive white smoke producing compositions, which incorporate an
oxidizer-fuel system, one affordable nitrogen-rich compound, two smoke forming agent/substance, binder, and inert
material as a filler. Affordable agents that are suitable for use with the current invention is a combination of trans-Bphenylacrylic acid and oil group consisting fatty acids & monosturated or saturated fats preferably one of the
mustard oil, avocado oil or other similar those having at least smoke point at 250 degree Celsius or at higher
temperature.
BACKGROUND OF THE INVENTION
002 Military operations are carried out at vast varieties of terrains and at various environment conditions, for which
effective and safe generation of white smoke poses a challenging pyrotechnic problems. The smoke must fulfil the
basic application of screening or signalling and in various contexts; it is desirable to have the capability to produce
smoke suitable for a wide variety of applications also. For example, in order to train fire fighters, it would be
advantageous to simulate specific types of Smoke produced by various fire conditions. For individuals working in a
fire-prone environment, Such as on an aircraft or ship, it would also be desirable to have the capability of simulating
smoke produced by a fire in order to provide a realistic fire drill.
003. Thus composition must have following properties: The composition must burn smoothly at low temperature. If
the burning temperature exceeds the smoke point and decomposition of the agents mentioned in this embodiment,
then it will decompose the agents and produce flames making it ineffective. Composition must have low ignition
temperature, but it must be stable during manufacturing and storage over the expected range of ambient
temperatures, which is generally -20 degree Celsius to 50 degree Celsius.
004. Composition must produce a sufficient volume of gas to disperse the by-products of chemical reaction into the
Surrounding environment.
005. Most existing smoke producing compositions have severe limitations. One of the limitations is that of toxicity.
Many Smoke-producing compositions incorporate materials that are severely toxic or become irritants when
Subjected to the heat necessary to produce Smoke. The molecules creating the white smoke must be of low toxicity
(including low carcinogenicity).
006. Already existing some white smoke compositions are having inconsistent burning rate leading to the failure of
primary function, for example compositions utilizing only trans-B-phenylacrylic acid as an agent burn slow and at
very inconsistent rate which are of no use in military operations. Thus it is advantageous to have composition which
burns consistently and could be adjusted as per the requirement, because a too rapid combustion destroys the white
molecules, which gives the white colour to it. In contrast, a two slow combustion produces a Smoke yield of minimal
consequence and tends toward self-extinction of the combustion process. It is better to consider the effects of the
reaction thermodynamics by making an appropriate choice of the agents and the components of the composition
and by the conditions of the state of the composition.
007. Currently some manufacturers are using white colour dyes for making military grade white smoke, which are
polycyclic or aromatic amino, hydroxyl, azo and keto compounds, in which unsaturation conjugated with the
aromatic structure. Such compounds are known to cause chromosome mutations, which may lead to cancer. These
dyes are not readily available and even costs high enough. Therefore composition must have components which are
being manufactured in high enough quantities that won’t fall short in any critical times i.e. Chinese virus (COVID 19)
led to shut down of all major dye producers in its mainland leading to supply shortage of dye agent.
008. Generally smoke point values can vary greatly, depending on factors such as the oil utilized and acidity content,
otherwise known as free fatty acid (FFA). The more FFA it contains, the quicker it will breakdown and start smoking.
For example smoke point of mustard oil is approx. 249 degree Celsius, if the burning temperature is lower than
smoke point, then the breakdown of the oil won’t take place leading to condensing of the oil at the orifice of the
device or if the temperature is high above the smoke point, which is also known as flash point, then the vapours will
catch fire.
009. Another problem face by the available white smoke compositions is the production of slag/residue. The solid
residue reaction product contributes to the formation of waste products such as slag and solid clinkers. Such solid
waste materials tends to choke the nozzle hole which may lead to increase the release pressure due to which
temperature will rise inside the device body, can cause deterioration of the agents. Even deflagration can occur
which could result in fire hazard to the surrounding.
That is why in this invention such components are selected which produces uniform and porous slag. It is also known
that the extent of porosity of the slag regulates the smoke yield and favours heat exchange between the
components of the smoke generating composition.
010. Some known compositions have the drawback of burning at temperatures that are too high (400-800° C.) or
leave too many carbonaceous residues. These conditions destroy the smoke producing agents and even tend to
produce smoke of high temperature resulting in rapid ascent.
011. Some of these white smokes producing composition’s kindling point are high enough, which require initiatory
composition to ignite it. Another major drawback of using such mixtures is the hazard created by the creation of a
flame front at the moment of ignition of the initiatory composition. This invention does not require any such
initiatory composition, it can be ignited with the of available known fuse i.e. prime cambric fuse.
012. In summary, there is a need for effective smoke producing compositions. This need exists in both military and
civilian operations. However, many smoke producing compositions presently used are difficult to handle. Such
compositions are toxic and irritating i.e. one of the known available composition releases zinc chloride which is again
health hazardous chemical, requiring special precautions during use. Many Such compositions are also corrosive and
damaging to both electronic and mechanical equipment. Finally, some compositions produce an excess of heat and
flame, again limiting their usefulness and requiring that additional safety measures be taken. For these reasons,
conventional smoke producing compositions are found to be inadequate.
SUMMARY OF THE INVENTION
013. The general purpose of the present invention, which will be described subsequently in greater detail, is to
provide an improved pyrotechnic smoke producing composition that has all the advantages of the prior art and
overcomes the above mentioned disadvantages and drawbacks of the prior art.
To attain this, the preferred embodiment of the present invention essentially comprises a composition of an
oxidizer, a fuel, a flame retardant, an agent and filler. The oxidizer may be potassium chlorate. The fuel may be
starch, dextrose, lactose, and/or Sucrose. The flame retardant may be nitrogen-rich compounds i.e. Dicyandiamide.
The agent may be both oil group consisting fatty acids & monosturated or saturated fats and trans-B-phenylacrylic
acid. The composition may consist of on a mass basis oxidizer 15-35%, fuel 10-30%, oil type agent 05-25%, trans-Bphenylacrylic acid agent 10-55%, flame retardant 2-15%, binder 1-3% and inert material 5-15%. The composition may
be filled in grenade/signalling device body in pelletized form or in the form of a solid charge by body pressing
process.
014. There has thus been outlined; rather broadly, the more important features of the invention in order that the
detailed description thereofthat follows may be better understood and in order that the present contribution to the
art may be better appreciated.
DESCRIPTION OF THE CURRENT EMBODIMENT
015. The invention relates to a smoke-producing pyrotechnic composition and more particularly, is related to
generally cool-burning, environment friendly and non-corrosive Smoke producing compositions, which incorporate:
016. Oxidizer—a presently preferred oxidizer is Potassium Chlorate (KCLO3).
017. Fuel—a low energy fuel is preferred in order to volatilize the agents. Such fuels may include, for example,
starch, dextrose, lactose or sucrose. It is also preferred that the fuel produce gaseous reaction products capable of
carrying the Smoke producing agent into the environment. Sucrose is preferred in this invention as it decomposes at
a lower temperature around 140 degrees Celsius with potassium chlorate whereas trans-B-phenylacrylic acid & any
suitable oil agent have much higher decomposition temperature with potassium chlorate.
018. Two agents are together preferred; First one is oil group consisting fatty acids & monosturated or saturated fats
and second one is trans-B-phenylacrylic acid. As both the agents must have close temperature range of
decomposition with potassium chlorate, as trans-B-phenylacrylic acid decomposes around 260 degree Celsius
therefore suitable oil must have decomposition temperature close to it. Mustard oil’s smoke point is 250 degree
Celsius above which it starts decomposing; therefore mustard oil is preferred in the present invention.
019. Filler may be any one of a number of fillers such as kieselguhr or kaolinite.
020. Flame retardant—at least one affordable nitrogen-rich compound selected from the group consisting of
guanidine nitrate, guanidine carbonate or dicyandiamide, aZodicarbonamide, melamine, and oxamide.
021. In this present invention in which two smoke agents are combined have several advantages:
022. Cool burning of the composition, which releases gases at low temperature, with a tendency to settle down on
surrounding surface making it thick and dense for smoke screen.
023. Adjustable burning rate of the composition, by adjusting the percentage ratio of their combination, as per the
requirement for screening or signalling.
024. Oil agent avoids the requirement of any solvent in mixing process, hence reduces the manufacturing cost and
makes the process environment friendly.
025. Oil agent makes the composition non-hygroscopic, which improves the self-life of the product.
026. In general, if one agent is used to produce white smoke then it will never execute the characteristics of military
application, for example if only trans-B-phenylacrylic acid is used then the burning rate will be slow and inconsistent
on the other hand if only oil is used then the composition has the vigorous burn rate, low density and tendency to
catch flame easily. In order to overcome above mentioned disadvantages, this combination has been invented.
027. To check the efficacy of various white smokes producing compositions of present invention were placed in Highdensity polyethylene (HDPE) grenade body. The compositions were compacted as pressed pellets , each body were
filled by 5 no. of pellets of approx. 20 gram each, summing up the total pyrotechnic filling to approx. 100 gram in
each body with prime cambric fuse. All the samples were ignited with prime cum delay detonator (PCDD) with a
delay of 2.5-4 seconds; in every test their ignition time and flame, burning time, slag flares, HDPE body status, smoke
density and smoke volume were recorded. The result of these tests is summarized in table 1 & 2.
Table 1
Ingredients Particle size CN16 CN66 CN69
Potassium chlorate <125 micron 28.5% 28.5% 27.5%
Sucrose <150 micron 18.5% 18.5% 17.5%
Dicyandiamide <150 micron - 5% 5%
Mustard oil n/a 15% 10% 10%
Trans-B-phenylacrylic acid n/a 25.5% 29% 31%
Kieselguhr <75 micron 11% 9% 9%
Nitrocellulose n/a 1.5% - -
Table 2
SAMPLE COMPOSITION
WEIGHT
IGNITION
TIME
SMOKE VOLUME
(INDOOR TESTING)
BURN
TIME
FLAME SLAG
FLARES
TEMPERATURE
CN16 98 grams 2 seconds 550 cubic meter 28 Sec. 2 sec. Yes <310⁰C
CN66 101 grams 4 Seconds 800 cubic meter 42 Sec. NO NO <210⁰C
CN69 99 grams 2 seconds 900 cubic meter 45 Sec. NO NO < 200⁰C
028. In above mentioned composition CN16, nitrocellulose is used as plasticiser & binder; it can be added to provide
extra binding strength to the pellets so that they could withstand the wear and tear of transportation before being
assembled.
029. It is clear from the above mentioned test results that the combination of two smoke agents with specifically
picked other ingredients has many advantages over available conventional formulations. First, goal of a current
invention is to burn with sufficient intensity to volatize the component of the composition to produce high volume of
dense & environment friendly white smoke. Secondly, it must be very economical to manufacture it.
030. Current embodiment of a pyrotechnic white smoke producing composition have been described in detail, it
should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and
scope of the invention.
031. With respect to the above description then, it is to be realized that the optimum dimensional relationships for
the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation,
assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships
and described in the specification are intended to be encompassed by the present invention.
032. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since
numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the
invention to the exact construction and operation shown and described, and accordingly, all suitable modifications
and equivalents maybe resorted to, falling within the scope of the invention.

WE CLAIM

1. A pyrotechnic white smoke composition comprising: an oxidizer; a fuel; a flame retardant; inert material; binder and combination of two type of agents.
2. The composition of claim 1 wherein the oxidizer is potassium chlorate.
3. The composition of claim 1 wherein the fuel is at least one of the groups consisting of sucrose, dextrose, lactose, and starch.
4. The composition of claim 1 wherein the flame retardant is at least one of the group consisting of dicyandiamide, guanidine nitrate, guanidine carbonate, azodicarbonamide, melamine, and oxamide.
5. The composition of claim 1 wherein the inert material may be any one of the kieselguhr or kaolinite.
6. The composition of claim 1 wherein the binder may be added from the selected group consisting of nitrocellulose, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinylester, and polyvinyl ether.
7. The composition of claim 1 wherein the one type of agent is of the oil group consisting fatty acids and monosturated or saturated fats i.e. mustard oil, avocado oil, safflower oil and soybean oil.
8. The composition of claim 1 wherein the second type of agent is trans-B-phenylacrylic acid.
9. The composition of claim 1 wherein the composition comprises on a mass basis oxidizer 15-35%, fuel 10-30%, oil type agent 05-25%, trans-B-phenylacrylic acid agent 10-55%, flame retardant 2-15%, binder 1-3% and inert material 5-15%. , Description:FIELD OF THE INVENTION
001 The present invention relates to a white smoke composition, which costs more economical to manufacture and environment friendly which can be used for signalling or screening purposes in military exercises or in some other smoke requiring activities. Various devices and compositions are presently used for such purposes are not economical to produce and not even non-toxic & environment friendly. The present invention is related to generally cool-burning, environment friendly, and non-corrosive white smoke producing compositions, which incorporate an oxidizer-fuel system, one affordable nitrogen-rich compound, two smoke forming agent/substance, binder, and inert material as a filler. Affordable agents that are suitable for use with the current invention is a combination of trans-B-phenylacrylic acid and oil group consisting fatty acids & monosturated or saturated fats preferably one of the mustard oil, avocado oil or other similar those having at least smoke point at 250 degree Celsius or at higher temperature.
BACKGROUND OF THE INVENTION
002 Military operations are carried out at vast varieties of terrains and at various environment conditions, for which effective and safe generation of white smoke poses a challenging pyrotechnic problems. The smoke must fulfil the basic application of screening or signalling and in various contexts; it is desirable to have the capability to produce smoke suitable for a wide variety of applications also. For example, in order to train fire fighters, it would be advantageous to simulate specific types of Smoke produced by various fire conditions. For individuals working in a fire-prone environment, Such as on an aircraft or ship, it would also be desirable to have the capability of simulating smoke produced by a fire in order to provide a realistic fire drill.
003. Thus composition must have following properties: The composition must burn smoothly at low temperature. If the burning temperature exceeds the smoke point and decomposition of the agents mentioned in this embodiment, then it will decompose the agents and produce flames making it ineffective. Composition must have low ignition temperature, but it must be stable during manufacturing and storage over the expected range of ambient temperatures, which is generally -20 degree Celsius to 50 degree Celsius.
004. Composition must produce a sufficient volume of gas to disperse the by-products of chemical reaction into the Surrounding environment.
005. Most existing smoke producing compositions have severe limitations. One of the limitations is that of toxicity. Many Smoke-producing compositions incorporate materials that are severely toxic or become irritants when Subjected to the heat necessary to produce Smoke. The molecules creating the white smoke must be of low toxicity (including low carcinogenicity).
006. Already existing some white smoke compositions are having inconsistent burning rate leading to the failure of primary function, for example compositions utilizing only trans-B-phenylacrylic acid as an agent burn slow and at very inconsistent rate which are of no use in military operations. Thus it is advantageous to have composition which burns consistently and could be adjusted as per the requirement, because a too rapid combustion destroys the white molecules, which gives the white colour to it. In contrast, a two slow combustion produces a Smoke yield of minimal consequence and tends toward self-extinction of the combustion process. It is better to consider the effects of the reaction thermodynamics by making an appropriate choice of the agents and the components of the composition and by the conditions of the state of the composition.
007. Currently some manufacturers are using white colour dyes for making military grade white smoke, which are polycyclic or aromatic amino, hydroxyl, azo and keto compounds, in which unsaturation conjugated with the aromatic structure. Such compounds are known to cause chromosome mutations, which may lead to cancer. These dyes are not readily available and even costs high enough. Therefore composition must have components which are being manufactured in high enough quantities that won’t fall short in any critical times i.e. Chinese virus (COVID 19) led to shut down of all major dye producers in its mainland leading to supply shortage of dye agent.
008. Generally smoke point values can vary greatly, depending on factors such as the oil utilized and acidity content, otherwise known as free fatty acid (FFA). The more FFA it contains, the quicker it will breakdown and start smoking. For example smoke point of mustard oil is approx. 249 degree Celsius, if the burning temperature is lower than smoke point, then the breakdown of the oil won’t take place leading to condensing of the oil at the orifice of the device or if the temperature is high above the smoke point, which is also known as flash point, then the vapours will catch fire.
09. Another problem face by the available white smoke compositions is the production of slag/residue. The solid residue reaction product contributes to the formation of waste products such as slag and solid clinkers. Such solid waste materials tends to choke the nozzle hole which may lead to increase the release pressure due to which temperature will rise inside the device body, can cause deterioration of the agents. Even deflagration can occur which could result in fire hazard to the surrounding.
That is why in this invention such components are selected which produces uniform and porous slag. It is also known that the extent of porosity of the slag regulates the smoke yield and favours heat exchange between the components of the smoke generating composition.
010. Some known compositions have the drawback of burning at temperatures that are too high (400-800° C.) or leave too many carbonaceous residues. These conditions destroy the smoke producing agents and even tend to produce smoke of high temperature resulting in rapid ascent.
011. Some of these white smokes producing composition’s kindling point are high enough, which require initiatory composition to ignite it. Another major drawback of using such mixtures is the hazard created by the creation of a flame front at the moment of ignition of the initiatory composition. This invention does not require any such initiatory composition, it can be ignited with the of available known fuse i.e. prime cambric fuse.
012. In summary, there is a need for effective smoke producing compositions. This need exists in both military and civilian operations. However, many smoke producing compositions presently used are difficult to handle. Such compositions are toxic and irritating i.e. one of the known available composition releases zinc chloride which is again health hazardous chemical, requiring special precautions during use. Many Such compositions are also corrosive and damaging to both electronic and mechanical equipment. Finally, some compositions produce an excess of heat and flame, again limiting their usefulness and requiring that additional safety measures be taken. For these reasons, conventional smoke producing compositions are found to be inadequate.
SUMMARY OF THE INVENTION
013. The general purpose of the present invention, which will be described subsequently in greater detail, is to provide an improved pyrotechnic smoke producing composition that has all the advantages of the prior art and overcomes the above mentioned disadvantages and drawbacks of the prior art.
To attain this, the preferred embodiment of the present invention essentially comprises a composition of an oxidizer, a fuel, a flame retardant, an agent and filler. The oxidizer may be potassium chlorate. The fuel may be starch, dextrose, lactose, and/or Sucrose. The flame retardant may be nitrogen-rich compounds i.e. Dicyandiamide. The agent may be both oil group consisting fatty acids & monosturated or saturated fats and trans-B-phenylacrylic acid. The composition may consist of on a mass basis oxidizer 15-35%, fuel 10-30%, oil type agent 05-25%, trans-B-phenylacrylic acid agent 10-55%, flame retardant 2-15%, binder 1-3% and inert material 5-15%. The composition may be filled in grenade/signalling device body in pelletized form or in the form of a solid charge by body pressing process.
014. There has thus been outlined; rather broadly, the more important features of the invention in order that the detailed description thereofthat follows may be better understood and in order that the present contribution to the art may be better appreciated.
DESCRIPTION OF THE CURRENT EMBODIMENT
015. The invention relates to a smoke-producing pyrotechnic composition and more particularly, is related to generally cool-burning, environment friendly and non-corrosive Smoke producing compositions, which incorporate:
016. Oxidizer—a presently preferred oxidizer is Potassium Chlorate (KCLO3).
017. Fuel—a low energy fuel is preferred in order to volatilize the agents. Such fuels may include, for example, starch, dextrose, lactose or sucrose. It is also preferred that the fuel produce gaseous reaction products capable of carrying the Smoke producing agent into the environment. Sucrose is preferred in this invention as it decomposes at a lower temperature around 140 degrees Celsius with potassium chlorate whereas trans-B-phenylacrylic acid & any suitable oil agent have much higher decomposition temperature with potassium chlorate.
018. Two agents are together preferred; First one is oil group consisting fatty acids & monosturated or saturated fats and second one is trans-B-phenylacrylic acid. As both the agents must have close temperature range of decomposition with potassium chlorate, as trans-B-phenylacrylic acid decomposes around 260 degree Celsius therefore suitable oil must have decomposition temperature close to it. Mustard oil’s smoke point is 250 degree Celsius above which it starts decomposing; therefore mustard oil is preferred in the present invention.
019. Filler may be any one of a number of fillers such as kieselguhr or kaolinite.
020. Flame retardant—at least one affordable nitrogen-rich compound selected from the group consisting of guanidine nitrate, guanidine carbonate or dicyandiamide, aZodicarbonamide, melamine, and oxamide.
021. In this present invention in which two smoke agents are combined have several advantages:
022. Cool burning of the composition, which releases gases at low temperature, with a tendency to settle down on surrounding surface making it thick and dense for smoke screen.
023. Adjustable burning rate of the composition, by adjusting the percentage ratio of their combination, as per the requirement for screening or signalling.
024. Oil agent avoids the requirement of any solvent in mixing process, hence reduces the manufacturing cost and makes the process environment friendly.
025. Oil agent makes the composition non-hygroscopic, which improves the self-life of the product.
026. In general, if one agent is used to produce white smoke then it will never execute the characteristics of military application, for example if only trans-B-phenylacrylic acid is used then the burning rate will be slow and inconsistent on the other hand if only oil is used then the composition has the vigorous burn rate, low density and tendency to catch flame easily. In order to overcome above mentioned disadvantages, this combination has been invented.
027. To check the efficacy of various white smokes producing compositions of present invention were placed in High-density polyethylene (HDPE) grenade body. The compositions were compacted as pressed pellets , each body were filled by 5 no. of pellets of approx. 20 gram each, summing up the total pyrotechnic filling to approx. 100 gram in each body with prime cambric fuse. All the samples were ignited with prime cum delay detonator (PCDD) with a delay of 2.5-4 seconds; in every test their ignition time and flame, burning time, slag flares, HDPE body status, smoke density and smoke volume were recorded. The result of these tests is summarized in table 1 & 2.
Table 1
Ingredients Particle size CN16 CN66 CN69
Potassium chlorate <125 micron 28.5% 28.5% 27.5%
Sucrose <150 micron 18.5% 18.5% 17.5%
Dicyandiamide <150 micron - 5% 5%
Mustard oil n/a 15% 10% 10%
Trans-B-phenylacrylic acid n/a 25.5% 29% 31%
Kieselguhr <75 micron 11% 9% 9%
Nitrocellulose n/a 1.5% - -

Table 2
SAMPLE COMPOSITION
WEIGHT IGNITION
TIME SMOKE VOLUME
(INDOOR TESTING) BURN
TIME FLAME SLAG
FLARES TEMPERATURE
CN16 98 grams 2 seconds 550 cubic meter 28 Sec. 2 sec. Yes <310°C
CN66 101 grams 4 Seconds 800 cubic meter 42 Sec. NO NO <210°C
CN69 99 grams 2 seconds 900 cubic meter 45 Sec. NO NO < 200°C

028. In above mentioned composition CN16, nitrocellulose is used as plasticiser & binder; it can be added to provide extra binding strength to the pellets so that they could withstand the wear and tear of transportation before being assembled.
029. It is clear from the above mentioned test results that the combination of two smoke agents with specifically picked other ingredients has many advantages over available conventional formulations. First, goal of a current invention is to burn with sufficient intensity to volatize the component of the composition to produce high volume of dense & environment friendly white smoke. Secondly, it must be very economical to manufacture it.
030. Current embodiment of a pyrotechnic white smoke producing composition have been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention.
031. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships and described in the specification are intended to be encompassed by the present invention.
032. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents maybe resorted to, falling within the scope of the invention.