Note: Descriptions are shown in the official language in which they were submitted.
WO 2020/210318
PCT/US2020/027216
LOW-SMOKE PYROTECHNIC COMPOSITION
CROSS-REFERENCE TO RELATED APPLICATIONS
mon This Application claims priority to U.S. Provisional Patent
Application Serial No.
62/832,003, filed on April 10, 2019, to Lyle Salmi et al., entitled "Low-Smoke
Pyrotechnic
Composition," currently pending, the entire disclosure of which is
incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to ingredients or
components for use in
pyrotechnics, and more specifically, as a low-smoke alternative to black
powder used in
pyrotechnics.
BACKGROUND OF THE INVENTION
[0003] Black powder has been used in pyrotechnic devices for thousands
of years. It is an
intimate mixture of approximately 75% potassium nitrate, 15% charcoal, and 10%
sulfur.
While its initial development was geared towards using it as an explosive
weapon, its uses
quickly expanded into the civil engineering and entertainment sectors. Its
historic beginnings
should be of no surprise, as there are many positive characteristics that make
black powder an
attractive composition for use in pyrotechnics. Firstly, black powder is
readily ignitable due
to the presence of sulfur and its low melting point. Secondly, black powder is
made from
components that are readily available and relatively inexpensive. Finally,
black powder not
only is able to propel or "lift" other pyrotechnic compositions effectively,
it also forms a
1
CA 03132944 2021- 10- 8
WO 2020/210318
PCT/US2020/027216
large amount of hot, solid particles during combustion which facilitate the
ignition of
secondary pyrotechnic compositions
[00041 There is a high demand for black powder replacements that
provide acceptable bum
rates upon combustion, generate high volumes of gas, and successfully initiate
the
combustion of and propel other pyrotechnic compositions. Black powder used in
current
pyrotechnic devices is undesirable for certain applications due to the fact
that it typically
produces substantial solid by-products from the composition's combustion in
the form of
smoke and other solid particulate matter. Current black powder replacements
typically fail to
reliably ignite secondary pyrotechnic compositions.
[00051 Accordingly, a need exists for gas generating compositions
suitable for use in
pyrotechnic applications that require similar gas-generating and heat transfer
properties while
also reducing smoke output
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention is directed to a low-smoke, pyrotechnic
composition that can be
suitably used in applications where it is desirable to have minimal smoke
production or other
solid particulate matter production resulting from the combustion of the
composition.
[00071 The low-smoke, pyrotechnic composition of the present invention
includes Ceric
Ammonium Nitrate (CAN) (chemical formula: FIKINIsCe018) as an oxidizing agent
in order to
limit the production of solid by-product, including smoke generation, during
combustion of
the composition. The Celtic Ammonium Nitrate within the low-smoke, pyrotechnic
composition generates large amounts of oxygen useful in propagating combustion
and
generates nitrogen gas useful in propulsion, while also providing noticeably
reduced smoke
and particulate matter generation during combustion as compared to other
common oxidizers.
2
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
[0008]
According to one embodiment of
the present invention, the low-smoke, pyrotechnic
composition can include a fuel source, a stabilizer, a binder, and Ceric
Ammonium Nitrate as
an oxidizer. In certain embodiments, the composition may include additional
oxidizing agents
in addition to Ceric Ammonium Nitrate; however, Ceric Ammonium Nitrate must be
present
in the composition of the present invention. The low-smoke, pyrotechnic
composition in
accordance with the various embodiments of the present invention may include
any suitable
fuel source or fuel sources, including without limitation, metal and non-metal
fuel sources,
any suitable type of stabilizing agent or agents, and any suitable type of
binding agent or
agents.
[0009] According to one embodiment of the present invention, the low-
smoke, pyrotechnic
composition can include 20-80 percent by weight Ceric Ammonium Nitrate, 5-60
percent by
weight the fuel source(s), 1-20 percent by weight the stabilizer(s), and 0-15
percent by weight
the binder(s).
[0010] The low-smoke, pyrotechnic composition may also include a burn
rate catalyst in
accordance with one or more embodiments. The bum rate catalyst may include any
suitable
type or types of burn rate catalysts or heat generating compounds. The
selection of the
particular bum rate catalyst or heat generating compound, or a combination
thereof, may be
selected based at least in part on the desired effect and particular
pyrotechnic application.
[0011] According to one embodiment of the present invention, the low-
smoke, pyrotechnic
composition can include Cede Ammonium Nitrate as an oxidizer, Nitrocellulose
as a non-
metal fuel source, Titanium as a metal fuel source, Cyanoguanidine as a
stabilizer, Cupric
Oxide as a bum rate catalyst, and any suitable binder compound. In additional
embodiments,
one or more fuel sources, stabilizers, bum rate catalysts and/or oxidizers may
be added to the
low-smoke, pyrotechnic composition depending on the particular application.
3
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
[0012]
According to a specific
embodiment of the present invention, the low-smoke,
pyrotechnic composition can include approximately 30-40% by weight Ceric
Ammonium
Nitrate (oxidizer), approximately 45-55% by weight Nitrocellulose (non-metal
fuel source),
approximately 0.1-3,0% by weight Cyanoguanidine (stabilizer), approximately 5-
10% Cupric
Oxide (bum rate catalyst), and approximately 0-15% of a suitable binder
material.
[0013] According to a specific embodiment, the low-smoke, pyrotechnic
composition can
include approximately 36.7% by weight of Ceric Amrnoniwn Nitrate (---50 um),
approximately 51,4% by weight of Nitrocellulose, approximately 3,7% by weight
Titanium (-
325 mesh), approximately 0.9% by weight Cyanoguanidine, approximately 73% by
weight
of Cupric Oxide, and approximately 0-15% by weight of a binder material.
[0014] Other aspects and advantages of the present invention will be
apparent from the
following detailed description of the preferred embodiments.
DETAILED DESCRIPTION OF THE INVENTION
100151 The following detailed description of the invention references
specific embodiments
in which the invention can be practiced. The embodiments are intended to
describe aspects of
the invention in sufficient detail to enable those skilled in the art to
practice the invention.
Other embodiments can be utilized and changes can be made without departing
from the
scope of the present invention. The present invention is defined by the
appended claims and
the description is, therefore, not to be taken in a limiting sense and shall
not limit the scope of
equivalents to which such claims are entitled.
[0016] The present invention is directed to a low-smoke, pyrotechnic
composition that can be
used in pyrotechnic applications where it is desirable to have a minimal
amount of smoke or
other solid particulate matter produced as a result of combustion of the
composition. The
low-smoke, pyrotechnic composition of the present invention can be utilized in
connection
4
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
illuminating pyrotechnic compositions and/or propellant compositions depending
on the
desired application. For example, the low-smoke, pyrotechnic composition of
the present
invention may be utilized to create an illuminating light, flash or flame,
heat and/or sound in
connection with the combustion of the composition while limiting the overall
production of
smoke generated in connection with the chemical reaction and combustion.
[0017] The principal component in the low-smoke, pyrotechnic
composition of the present
invention is Ceric Ammonium Nitrate, which is used as an oxidizer. Ceric
Ammonium
Nitrate is an inorganic compound with the formula (N1-14)2Ce(NO3)6 (chemical
formula:
H8N8Ce018) and is often used as an oxidant in organic synthesis. Ceric
Ammonium Nitrate
(CAN) can also be referred to as Diammonium cerium hexanitrate, Diammonium
hexanitratocerate(2-), and Ammonium cerium nitrate (VAN). CAN is used as the
main
oxidizing agent in the low-smoke, pyrotechnic composition and limits the
production of solid
by-product, including smoke generation during combustion of the composition.
[0018] Ceric Ammonium Nitrate is necessary in the low-smoke,
pyrotechnic composition of
the present invention, as it generates large amounts of oxygen useful in
propagating
combustion, and nitrogen gas useful in propulsion; it is also readily
ignitable in the presence
of organic fuels. CAN has likely found limited use in the pyrotechnics
industry due to
availability issues as well as its ready ability to oxidize various materials
at room temperature
when solvated.
[0019] Decomposition of one gram of Ceric Ammonium Nitrate generates
0.53 grams of
oxygen, 0.2 grams of nitrogen, and 0.1 grams of hydrogen. The mass of oxygen
generated is
comparable with other common oxidizers such as potassium nitrate (0.40 grams
of
oxygen/gram), potassium chlorate (0.39 grams of oxygen/gram), and potassium
perchlorate
(0.46 grams of oxygen/gram). The combustion of CAN forms 0.31 grams of Cerium
(IV)
Oxide and 033 grams of water vapor. After subtracting the oxygen that falls
out as Cerium
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
(li) Oxide and water vapor, 0.35 grams of free oxygen are left to participate
in the
combustion process. Using this information, it is found that over 69% of the
byproducts of
the decomposition of CAN are gaseous, and the combustion of formulations using
CAN as an
oxidizer have noticeably reduced smoke generation.
[0020] Ceric Ammonium Nitrate is also advantageous in the low-smoke,
pyrotechnic
composition of the present invention due to its low melting point. Sulfur's
implementation as
a low-melting point fuel in black powder has a drawback in that its presence
leads to large
amounts of solid sulfide byproducts that increases the smoke output of the
composition.
CAN's low melting point and high ignitability with organic fuels greatly
reduces the amount
of activation energy necessary for combustion and eliminates the need for
sulfur.
Furthermore, Ceric Ammonium Nitrate and its byproducts are environmentally
benign.
[0021] As illustrated in Table I below, according to one embodiment,
the low-smoke,
pyrotechnic composition of the present invention can include a fuel source, a
stabilizer, a
binder, and Ceric Ammonium Nitrate as an oxidizer. In certain embodiments,
additional
oxidizers may be utilized with the Cede Ammonium Nitrate; however, Ceric
Ammonium
Nitrate is the only specific component of the composition that cannot be
removed or replaced.
Additional oxidizers that may be used in conjunction with the Ceric Ammonium
Nitrate may
include, but are not limited to, nitrate salts, perchlorate salts, and metal
oxides. In certain
embodiments, the low-smoke pyrotechnic composition of the present invention
can include
one or more of each type of component comprising the composition. In such
embodiments,
the low-smoke, pyrotechnic composition can include at least one fuel source
agent, at least
one stabilizer agent, at least one binder agent, and at least one oxidizer
agent including at
least Ceric Ammonium Nitrate.
[0022] The fuel can be metal or non-metal source and the composition
can include multiple
fuel sources in certain embodiments. Non-limiting examples of suitable fuel
sources that may
6
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
be used in the low-smoke, pyrotechnic composition of the present invention can
include:
Nitrocellulose, Hexamine, Nitroguanidine, Red Gum, Titanium, Aluminum,
Magnesium,
Boron, Charcoal, Silicon, any transition metals or other types of fuel source
now known or
hereinafter developed or commonly used in the art.
[0023] The stabilizer can be any suitable stabilizing
agent, including without limitation:
Cyanoguanidine, Dicyanodiamide, 2-cy
anoguanidine, Guanidine-1 -carbonitrile,
Dipheny famine, Nitrodiphenylarnine, Akardite, Ethyl Centralite, Methyl
Centralite,
Carbonate salts, or other type of stabilizer now known or hereinafter
developed or commonly
used in the art.
[0024] The binder can be a suitable compound or substance that can
bind/bond the other
components of the low-smoke, pyrotechnic composition. Non-limiting examples of
a suitable
binder that may be used in the low-smoke gas-generating composition of the
present
invention can include: Ethylcellulose, Methylcellulose, Hydroxypropyl
methylcellulose,
Hydroxypropyl ethylcelltilose polyvinyl alcohol, Viton, Parlon, polyvinyl
pyrrolidone,
polyethylene glycol, polyethylene glycol-polyvinyl alcohol copolymer, epoxy
resins and their
appropriate, crosslinking compounds, or other binder agents now known or
hereinafter
developed or commonly used in the art.
[0025] TABLE I
[0026] Basic Formula for Low-Smoke Pyrotechnic Composition:
[0027] Formula A:
Range
[0028] Ceric Ammonium Nitrate (oxidizer)
20-80%
[0029] Fuel Source(s)
05-60%
[0030] Stabilizer(S)
01-20%
[0031] Binder(s)
00-15%
7
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
[0032] As illustrated in Table II below, the low-smoke gas generating
composition of the
present invention can also include at least one burn rate catalyst or heat
generating compound
or compounds depending on the desired effect and particular pyrotechnic
application.
According to one embodiment, the low-smoke, pyrotechnic composition of the
present
invention can include Cupric Oxide as a burn rate catalyst. Other potentially
suitable catalysts
can include, but are not limited to, Ferric Oxide, Titanium Dioxide, Bismuth
Trioxide,
Molybdenum Trioxide, barium peroxide, strontium peroxide, calcium peroxide,
chromic
oxide, silicon dioxide, manganese (II) oxide, boron oxide or other desired
compounds
commonly used in the art.
[0033] TABLE II
[0034] Basic Formula for Low-Smoke Pyrotechnic Composition:
[0035] Formula B:
Range
[0036] Ceric Ammonium Nitrate (oxidizer)
20-80%
[0037] Fuel Source(s)
05-60%
[0038] Stabilizer(s)
01-20%
[0039] Binder(s)
00-15%
[0040] Bum Rate Catalyst(s)
0.5-20%
[0041] As illustrated in Table III below, according to one
preferred embodiment of the
present invention, the low-smoke, pyrotechnic composition includes Ceric
Anunonium
Nitrate as an oxidizer, Nitrocellulose as a non-metal fuel source, Titanium as
a metal fuel
source, Cyanoguanidine as a stabilizer, Cupric Oxide as a burn rate catalyst,
and any suitable
binder compound. The table below illustrates this preferred formula for low-
smoke,
pyrotechnic composition. As shown the Ceric Ammonium Nitrate can have a
suitable range
of 20-80 percent by weight of the overall formula. In addition, the other
components of the
8
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
composition can vary substantially by percent by weight and can be replaced
with other
suitable compounds depending on the particular application.
[0042] TABLE III
[0043] Select Formula for Low-Smoke Pyrotechnic
Composition:
[0044] Formula C:
Range
[0045] Ceric Ammonium Nitrate (oxidizer)
20-80%
[0046] Nitrocellulose (non-metal fuel source)
00-60%
[0047] Titanium (metal fuel source)
05-20%
[0048] Cy anoguanidine (stabilizer)
01-05%
[0049] Cupric Oxide (burn rate catalyst)
0.5-20%
[0050] Binder
00-15%
100511 According to one preferred embodiment of the present
invention, the low-smoke,
pyrotechnic composition includes approximately 36.7% by weight of Cede
Ammonium
Nitrate (-50 urn), approximately 51.4% by weight of Nitrocellulose,
approximately 3.7% by
weight Titanium (-325 mesh), approximately 0.9% by weight Cy anoguanidine,
approximately 7,3% by weight of Cupric Oxide, and approximately 0-15% by
weight of a
binder material. The specific % by weights may vary depending on the
particular or desired
application and or the amount of binder material utilized. For example, the
particular amount
by weight of Ceric Ammonium Nitrate as an oxidizer may range between 36.0-
37.5%
according to certain embodiments or may range between 30-40% in other
embodiments_
Table IV below illustrates one specific embodiment of the low-smoke,
pyrotechnic
composition along with potential ranges (by percent weight) of each ingredient
or compound
included in the composition.
[0052] TABLE IV
[0053] Specific Formula for Low-Smoke Pyrotechnic
Composition:
9
CA 03132944 2021- 10- 8
WO 2020/210318
PCT/US2020/027216
[0054] Formula D:
Specific Amount Range
[0055] Ceric Ammonium Nitrate (oxidizer)
36.7% 30-400/e
[0056] Nitrocellulose (non-metal fuel source)
51.4% 45-55%
[0057] Cyanoguanidine (stabilizer)
0.9% 0.1-3.0%
[0058] Cupric Oxide (burn rate catalyst)
73% 5.0-10%
[0059] Binder
0.0% 00-15%
[0060] The low-smoke, pyrotechnic composition of the
present invention, as described,
herein results in minimal solid particulate and smoke by-product production
during the
combustion of the composition while still providing the desired burn
temperatures, burn rates
and other desired effects for various pyrotechnic applications. The Ceric
Ammonium Nitrate
is the key ingredient in the composition of the present invention that
produces comparable
performance characteristics to that of black powder while reducing or
eliminating its negative
attributes. In particular the inclusion of Ceric Ammonium Nitrate in the low-
smoke,
pyrotechnic composition of the present invention in accordance with the
percent by weight
ranges as described herein has the effect of producing limited smoke
generating during
combustion of the composition when compared to traditional pyrotechnic
compositions.
[0061] For safety and longevity reasons, the compositions must be
stabilized through the use
of hydrophobic binders such as epoxy resin, viton, or polyvinyl butyral. Any
number of
suitable manufacturing and production methods can be utilized in the
preparation of the low-
smoke pyrotechnic composition of the present invention depending on the
particular
embodiment, including without limitation, manufacturing and production methods
currently
used in the pyrotechnics industry or hereinafter developed, or any other
methods or
techniques used in the production of chemical compositions. The low-smoke
pyrotechnic
composition of the present invention has several potential benefits, including
without
limitation, tunable performance aspects through minimal formulation changes,
and the
CA 03132944 2021- 10-8
WO 2020/210318
PCT/US2020/027216
generation of mostly gaseous byproducts which increases performance while
lowering the
smoke output.
[0062] From the foregoing, it will be seen that this invention is one
well adapted to attain all
the ends and objects hereinabove set forth together with other advantages
which are obvious
and which are inherent to the structure_ It will be understood that certain
features and sub
combinations are of utility and may be employed without reference to other
features and sub
combinations. This is contemplated by and is within the scope of the claims.
[0063] The constructions described above are presented by way of
example only and are not
intended to limit the concepts and principles of the present invention. Thus,
there has been
shown and described several embodiments of a novel invention. As is evident
from the
foregoing description, certain aspects of the present invention are not
limited by the particular
details of the examples illustrated herein, and it is therefore contemplated
that other
modifications and applications, or equivalents thereof, will occur to those
skilled in the art_
The terms "having" and "including" and similar terms as used in the foregoing
specification
are used in the sense of "optional" or "may include" and not as "required".
Many changes,
modifications, variations and other uses and applications of the present
construction will,
however, become apparent to those skilled in the art after considering the
specification. All
such changes, modifications, variations and other uses and applications which
do not depart
from the spirit and scope of the invention are deemed to be covered by the
invention which is
limited only by the claims which follow.
11
CA 03132944 2021- 10-8
