Note: Descriptions are shown in the official language in which they were submitted.
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ANTITRAUMA P~-'~T
Backqround of th~ TnveDtion
1. Field Qf ~e ; nven~ion
The present invention relates to a material or
5 strueture that resists ballistic penetration and meehanieal
impaet forees. More speeifieally, the present invention
relates to a material that is comprised of a matri~ of
polymerie fibers in whieh a plurality of microspheres are
spread throughout.
10 2. Des~ril?tion of the Rela~ed l~r~.
The invention of linear polyamides (e.g., nylon,
nylon 6, etc ~, has lead to further research ~or new
synthetic textile fibers, polyester fibers, polyurethane
f ibers, etc . This research leads to the invention of a type
15 of fibers which have high heat resistance and high
resistance to mechanical strain. These new fibers are
classified under the generic name of "para amide ~ibers~
(or simply aramid ~ibers), and include the KEVLARR, NOMEXR
and TWARONR, three important mem.~bers of this group.
Aramid polymers are a product of the reaction of -
the amino groups o~ a p~ m;nnhpn7ene compound and the
acid groups o~ a terephtalic acid compound (The f irst
example of a para amide polymer in this series was obtained
from the polymerization of p-aminobenzoic aeid, coded PPD-
T) .
In view of its superior mechanical and dynamic
properties, its reduced expansion and thermal conductivity,
its exeellent abrasion resistance, heat resistance and
chemical inertia, the aramid fibers and in partieular,
KEVLARR and TWARONR have been used in a great number o~
applieations in the manufacture of ropes, laminated
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tissues, etc. Aramid fibers are also used in the field of
ballistic protection, both as soft body armors and heavy,
high coverage armors, instead of body armors and bullet-
resistant vests that are made of, for example, polyesters
5 f ibers or nylon f ibers .
The application of polymeric fiber materials in
ballistic protection replaced other integrated structures
with denser materials such as glass fibers or aluminum
fibers. The ballistic resistance of polymeric fibers is
10 greater than that of glass or aluminium fibers. It is
believed that ballistic resistance of fibers in general is
due to the f act that, as a conse~uence of the impact and
the penetration of the bullets, the yarns are stretched and
thus absorb the energy of the projectile and dissipate that
15 energy laterally (through the fibrous yarns which surround
the impact zone) and also di6sipate that energy
longitudinally in the direction of the proj ectile . Aramids,
the same as their predecessors, aliphatic polyamides and
polyesters, are used under the form of flexible structures
20 (of woven fibers arranged in juxtaposed layers or of masses
of felt-like (i.e unwoven) fibers having the thickness
determined by the degree of exposure to projectiles) or
rigid structures of laminate aramids for fragment and
bullet-resistant garments and body armor panels. These
25 structures and pieces are applicable for both soft armors
and heavy armors.
Materials used in ballistic protection should
meet the regulations of standard norms which vary in each
country. The standard norms establish the conditions to
30 measure the speed of pro~ectiles, and to measure
penetration of the projectile into the material to
determine the limit of the material. Ballistic resistance,
for example, is the maximum velocity at which a fired
bullet may be stopped and the bullet resistance corresponds
35 to a "Vso" value, which is defined a6 the velocity at which
the penetration probability is 50~.
.
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Another factor contemplated by the norms refers
to the body protection and is important for the design and
manufacture of personal body armors and garments. The body
protection is the magnitude and the prof ile of t~e
5 deformation in the armor backing material or support of a
bullet defense. This deformation, which for a certain
defense, depends on the caliber, the weight, the velocity
and the kind of bullet or fragment, may cause damage or ~~
bodily injuries, the severity of which also depends on the
10 point of impact, since part of the energy of each impact is
felt and received: in the area of the body which is in line ---
with the point of impact and results in traumas of a
particularly severe nature when they correspond to the -
hepatic region, the left iliac cavity, the spine, etc. The
maximum deformation of the rear part of a ballistic defense -~~
after the impact is called "trauma", and is quantitatively
expressed by lts depth (the length of the deformation in
the direction of the impact).
In practice, the ballistic protection (soft or
20 rigid) is obtained by panels (also called packets) that are
formed by a layer or a plurality of layers of fabrics made
of woven or felt-like (i.e unwoven) aramid fibers, such as
KEVI,AR 29R, KE~VLAR 49R, TWARON CT 930R, TWARON 1260R, etc.
~ach panel is covered by a hermetic, waterproof, flexible
25 cover or envelope having a predetermined thickness and
design depending on the level of protection desired and the
bullet parameters. Depending on each case, the flexible
cover may be backstitched in order to increase the density
of the fiber mass.
In laminated materials, the woven or unwoven
aramid fibers are combined with polyester resins, phenolic
resins, elastomers, and depending on each case, with carbon
fibers or ceramic fibers to form a structure to be applied
in heavy ballistic armors (e.g. helmets, defensive armors
3~ for vehicles, shelters or cabins, etc.)
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Trauma may be controlled by modifying the
thickness of the ballistic panels, the density of the fiber
mass, the weave pattern of the fibers, etc. ~dditionally,
trauma may be controlled by incorporating additional
5 laminates of antitrauma packets, aramid fillings or ceramic
plates which cover the whole or a part of the front or the
back of the ballistic panels.
SummarY o~ ~hP Iny~ntisn
It is an object of the present invention to
10 increase the ballistic resistance, the bullet penetration
and reduce the magnitude of the trauma of structures that
are resistant to impact and/or to ballistic penetration
It is a further obj ect of this invention to
provide an antitrauma packet to supplement the resistance
15 of the mechanical impact and/or the ballistic penetration
of structures formed by panels of woven, unwoven or
laminated polymeric fibers. The packet comprises at least
one layer or sheet which def ines a matrix of woven or
unwoven polymeric fibers including a plurality of hollow
20 microspheres.
It is another object of this invention to provide
an antitrauma packet to supplement the resistance to the
mechanical impact and/or the ballistic penetration of
structures formed by panels of woven or unwoven aramid
25 fibers. The packet comprising at least one layer or sheet
which includes a matrix of woven or unwoven aramid fibers
having a plurality of hollow microspheres which together
def ine a polymeric covering .
It is yet another object of this invention to
30 provide a garment for body ballistic protection of the type
which comprises a bullet-resistant panel formed by at least
one plate or sheet of woven or unwoven aramid fibers. The
panel acts as filling within a cover that is defined by a
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closed and waterproof covering and at least an additional
panel formed by a plurality of sheets formed by a matrix of
polymeric fibers, such as aramid fibers where a plurality
of hollow microspheres are scattered therein.
It is yet another object of the present invention
to provide an armor which comprises a reinforced structure
resistant to the mechanical impact which comprises a
plurality of layers of aramid fibers consolidated with
synthetic resins, such as polyester resins or phenolic
resins and as an additional antitrauma structure. At least
one packet is defined by a closed and waterproof envelope
having at least one of the layers or sheets of woven or
unwoven fibers, for e~ample, aramid fibers, where hollow
microspheres are scattered therein.
~rie~ Deqcri~tion of the Fiqure_
The above and still further objects, features and
advantages of the present invention will become apparent
upon consideration of the following detailed description of
a specific embodiment thereof, especially when taken in
conjuntion with the accompanying drawings wherein like
reference numerals in the various figures are u~ilized to
designate like components, and wherein:
Figure 1 shows an enlarged view of an antitrauma
layer according to the ~resent invention.
Figure 2 shows a graph representative of the
depth of the trauma in accordance with the data o~ Table 1.
DPt~ P~l Desçri~tion 9~ i~he PrPqPntl~ Pr~erred r ~ -~; tq
The antitrauma packet of the present invention
comprises a plurality of juxtaposed laminates or layers of
a substrate or matrix of woven or unwoven f ibers, as a
support for a plurality of hollow microspheres that are
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randomly scattered in the matrix.
These kinds of support materials per sé are well
known in art. These support materials have been used in the
manufacture of laminates, or as low weight reinforcing
5 material, to replace other known reinforcing materials,
such as liners or blankets made of reticulate woven
polyester fibers, glass fibers or aramid fibers, etc., all
of which have a heavier weight.
The present invention pref erably uses the
10 commercially available product known as CORE~TR 3~[owever,
it should be understood that the present invention should
not be limited to this product and the fiber/microsphere
component can comprise virtually any fiber product 80 long
as hollow microspheres are used as an additional component
15 for the antitrauma structures or materials.
COREr~T~ (a product of Lantor B .V. ) is in the
form of blankets or laminates of unwoven polyester fibers
and has a variable thickness and density. In the tests
conducted and explained hereinbelow, blankets having a
~o thickness of 2 moa were used. These blankets were 60~6 by
wei~ht of polyester fibers and 40~ by weight of hollow
polymeric microspheres. The blankets had a density of
approximately 40/g/m'/mm of thickness. The large number of
microspheres used in ~orming the blankets plays a
25 fl~n~m,on~l role in obtaining such reduced density levels.
The packet of the present invention should be
united with a number of laminates in accordance with the
level of supplemental protection required, which, of
cour6e, depends on the type of impact load that the
30 material is to withstand. For example, the impact load may
be from the velocity of a bullet when it refers to
ballistic defenses, or to the strength or the condition of
a certain mechanical impact when it refers to defenses
against purely mechanical aggressions or effects (bumper or
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fender structures) in the protection, for example, of
critical parts or areas of civil or military vehicles.
The antitrauma packet of this invention has
increased resistance to ballistic penetration and to
5 me~hAn;rAl impact. The material, which carries the
microspheres, in accordance with this invention, is a
reinforce~Lent of laminate materials, having a function
similar to that of other reinforcement materials, but which
is extremely lightweight.
In this invention, the fiber structure and the
microspheres make up a material having unexpected superior
antitrauma effects, as shown in the tests explained =.
hereinbelow .
The packet of this invention can be of the f orm
15 of units or panels with a ~9PtPrm; n.~l number of juxtaposed
sheets included in a hermetic envelope or cover The packet
may be coupled with convPn~;nnAl protection structures
formed by panels made of aramid fibers. Another possible
alternative is to associate the packet of the present
20 invention at the back of any of the known structures that
are resistant to ballistic penetration and/or mechanical
impact (such as KEVI,AR~ or TWARONR sheets or felts) . ~or
the purposes of this invention, the matrix on which the
microspheres are scattered does not depend on a particular
25 kind of f ibers or microspheres . The known material, the
COREM~T~ (polyester fibers and hollow polystyrene
microspheres) has been spe~ ;f;~ y mentioned herein and it
is considered that other woven or unwoven structures, such
as nylon, I~EVLAR or TWARON and compounds thereof, are
30 useful for the purpose of this invention and should be
considered within the scope thereof.
The microspheres distributed in the matrix are
hollow particles preferably with a 1 to 100 micron average
diameter The values of the microsphere diameters are
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indicated for illustrative purposes only. The microspheres
should preferably be hollow particles which are not so
small as to behave as a powder material nor so big as to be
virtual bores in the matrix. The embedding of microspheres
in a resin material is known from U.S. Patent No. 4.543.106
to Parekti, which is hereby incorporated by reference.
Fig. 1 shows a plurality of orifices or through
holes in a COREMAT product that have been produced by a
bullet The f ibers are shown in the background of the
drawing. A garment may be made in accordance with the
present invention by packing layers of E~EVLAR, or other
suitable fibrous material along with a layer of
fiber/microsphere component that have been attached to each
other, for example by sewing or VELCROR, etc, within an
envelope that is preferable waterproof.
Balli~ti~ T~t~ -
Comparative tests (i.e. without the antitrauma
panel) of ballistic penetration and depth of the trauma
were conducted by firing bullets of different caliber on a
20 target formed by a 40cm x 40cm panel made of monofilament
and microfilament KEVLAR or TWARON fibers, compacted in a
polyester backstitched covering having sealed edges.
The following Table shows the information
corresponding to one of these tests:
Table I
Surface pPnPtr~t;on of thP Bllllet ;n~n thP p~nPl ;n .
mill~ mPt~'rS
Caliber Without the With the
antitrauma panel antitrauma panel
30 9 mm 70 mm o
. 3 5 7 Magnum 3 5 . 0 mm 3 mm
.44 Magnum 43-44 mm 6 mm
,., .. . i
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The antitrauma panel in accordance with the
present invention, used in these tests was formed by lO
layers of 2 mm thick of COREMATP- formed by a non typical
polyester matrix (60~6 of weight) and hollow microspheres ~-
(4096 of weight), with a density of 40 g/m'/mm thickness
Figure 2 shows the antitrauma effect which is
verified by supplementing a conventional panel of Kevlar
fibers with a package of 12 COREMATR laminates. The COREMATR
laminates and the Kevlar were included inside an envelope
10 made of oil cloth, i e. they were loose within a tight
envelope thus forming a monolitic structure The envelope
was sewed and the Kevlar and the Coremat laminate were held
together Lnside it. The set of 12 COREMATR laminates weighs
40g. These laminates reduce the ballistic deformation of a
15 conventional backing for a 44 Magnum gun from 43 mm to 6 0
mm
