BALLISTIC RESISTANT FLEXIBLE STRUCTURE
FIELD OF THE INVENTION
[0001] The present invention relates generally to protective devices. Particularly,
the present invention relates to ballistic resistant flexible structures for facilitating Low Back Face Signature (BFS) or increased protection against trauma.
BACKGROUND OF THE INVENTION
[0002] Protective devices, such as bulletproof vests, shields, combat helmets,
bombsuits, bomb suppression blankets, mine protection garments and the like are used by law enforcement agencies such as police, military, and the like for protection. These protective devices may also be used by other persons for their protection. Although, these protective devices stops penetration of the projectile, these devices may allow the kinetic energy of the projectile to be transferred through the protective devices, such as bullet proof vest, directly to the body of the wearer that might cause injuries to bone or any other body parts of the wearer.
[0003] In prior art, the protective devices, such as the protective vests are
comprised of layers of woven and non-woven fabrics or of nylon, aramid and the like. Although, these protective vests may be composed of high tenacity fibers and shows high resistant to bullet penetration, however, when a bullet strikes these layered protective vests, the impact load may cause a bulge to develop which deforms the back surface of the protective vests. Since the protective vests are worn adjacent to the body of the wearer, this bulge 'deformation' may extend into the body of the wearer. If the deformation is large, tissue damage or "trauma" may occur.
[0004] Traditionally, for increasing protection against trauma, the protective vests
increases number of layers of ballistic resistant materials. However, increasing the number of layers results in increased weight and areal density. However, increasing number of layers results

in increasing the overall weight of the protective vests. More specifically, every extra ounce may hamper the mobility and the combat performance of the law enforcement agencies. Further, increasing number of layers result in increasing the overall areal density of the protective vests. Accordingly, the prior art protective devices have comparatively increased areal density. Additionally, the prior art protective devices are unable to provide additional protection required in view of the improvements in the modem weapons.
[0005] Accordingly, there exists a need of a ballistic resistant flexible structure
that provides increased protection against trauma or Back Face Signature (BFS). Further, there is need of a ballistic resistant flexible structure that has comparatively less mass. Still further, there is need of a ballistic resistant flexible structure that has comparatively reduced areal density. Moreover, there is a need of a ballistic resistant flexible structure that facilitates increased mobility and combat performance to the law enforcement agencies. Also, there is a need of a ballistic resistant flexible structure that provides additional protection level required in view of the improvements in the modem weapons.
OBJECTS OF THE INVENTION
[0006] An object of the present invention is to provide a ballistic resistant flexible
stmcture that provides increased protection against trauma or Back Face Signature (BFS).
[0007] Yet another object of the present invention is to provide a ballistic
resistant flexible stmcture that apart from providing increased protection against trauma or Back Face Signature (BFS) provides increased protection against fragments, such as bullets, shrapnel and the like.
[0008] Still another object of the present invention is to provide a ballistic
resistant flexible stmcture that has comparatively reduced areal density.

[0009] Further, an object of the present invention is to provide a ballistic resistant
flexible structure that facilitates increased mobility and combat performance to the law enforcement agencies.
[0010] Furthermore, an object of the present invention is to provide a ballistic
resistant flexible structure that is adapted to provide soft cushion effect to a body portion of a user.
[0011] Also, an object of the present invention is to provide a ballistic resistant
flexible structure that has comparatively less mass.
[0012] Additionally, an object of the present invention is to provide a ballistic
resistant flexible structure that has softness and additional flexibility.
SUMMARY OF THE INVENTION
[0013] In one aspect the present invention provides a ballistic resistant flexible
structure. The ballistic resistant flexible structure includes a plurality of fragment resistant woven fabric layers, at least one thermoplastic polymer layer and at least one foam layer. The plurality of fragment resistant woven fabric layers includes a first set of fragment resistant woven fabric layers, a second set of fragment resistant woven fabric layers and a third set of fragment resistant woven fabric layers. The plurality of thermoplastic polymer layers is disposed parallel between the first set of fragment resistant woven fabric layers and the second set of fragment resistant woven fabric layers, the plurality of foam layers is disposed parallel to the plurality of second set of fragment resistant woven fabric layers and the third set of fragment resistant woven fabric layers is disposed parallel to the plurality of foam layers.
[0014] In one embodiment of the present invention, the plurality of thermoplastic
polymer layers is of polycarbonate.

[0015] In another embodiment of the present invention, the plurality of
thermoplastic polymer layers is of polypropylene.
[0016] The plurality of fragment resistant woven fabric layers may be composed
of aramid fabrics.
[0017] Alternatively, the plurality of fragment resistant fabric layers may be
composed of unidirectional aramid fabrics.
[0018] Typically, the first set of fragment resistant woven fabric layers includes
about 04 to 40 fragment resistant woven fabric layers.
[0019] Further, the second set of fragment resistant woven fabric layers may
include about 01 to 04 fragment resistant woven fabric layers.
[0020] Similarly, the third set of fragment resistant woven fabric layers includes
about 01 to 04 fragment resistant woven fabric layers.
[0021] In one embodiment of the present invention, the number of foam layers is
about 01 to 12.
[0022] In another embodiment of the present invention, the number thermoplastic
polymer layers is about 01 to 08.
[0023] Typically, the plurality of thermoplastic polymer layers has an areal
density in the range of 80-500 gsm.
[0024] In another aspect the present invention provides a ballistic resistant
flexible structure. The ballistic resistant flexible structure includes a plurality of thermoplastic polymer layers and at least one foam layer. The at least one foam layer is disposed parallel amongst the plurality of thermoplastic polymer layers.

BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The advantages and features of the present invention will become better
understood with reference to the following detailed description taken in conjunction with the accompanying drawings, wherein like elements are identified with like symbols. Further, it is to be understood that drawings are to be used for the purposes of exemplary illustration only and not as a definition of the limits of the invention:
[0026] FIG. 1 illustrates a schematic representation of a ballistic resistant flexible
structure, in accordance with an embodiment of the present invention;
[0027] FIG. 2 illustrates a schematic representation of a ballistic resistant flexible
structure, in accordance with another embodiment of the present invention;
[0028] FIG. 3 illustrates a schematic representation of a ballistic resistant flexible
structure, in accordance with yet another embodiment of the present invention; and
[0029] FIG. 4 illustrates a schematic representation of a ballistic resistant flexible
structure, in accordance with yet another embodiment of the present invention;
[0030] Like reference numerals refer to like parts throughout the description of
several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0031] The exemplary embodiments described herein detail for illustrative
purposes are subject to many variations in structure and design. It should be emphasized, however, that the present invention is not limited to a particular ballistic resistant flexible Structure, as shown and described. It is understood that various omissions and substitutions of

equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the present invention.
[0032] The terms "first," "second," and the like, herein do not denote any order,
quantity, or importance, but rather are used to distinguish one element from another, and the terms "a" and "an" herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
[0033] The present invention provides a ballistic resistant flexible structure such
as but not limited to a fragment resistant vest, a shield, a combat helmet, a bomb suppression blanket, a mine protection garment and the like, for providing increased protection against trauma or Back Face Signature (BFS). Also, the ballistic resistant flexible structure of the present invention apart from providing increased protection against trauma or Back Face Signature (BFS) provides increased protection against fragments, such as bullets, shrapnel and the like. The ballistic resistant flexible structure of the present invention adapted to provide soft cushion effect to a body portion of a user and deforms incoming projectile or threat and entraps it inside. Further, the ballistic resistant flexible structure of the present invention is an integrated combination of layers of projectile resistant materials that may be contoured to any shape and size to meet the protection requirements for any body part or whole body structure.
[0034] Referring to FIG.l, a ballistic resistant flexible structure 100 is depicted,
in accordance with one embodiment of the present invention. The ballistic resistant flexible structure 100 includes a plurality of fragment resistant woven fabric layers, such as a plurality of woven aramid fabric layers, at least one thermoplastic polymer layer, such as at least one layer of polycarbonate 104 and at least one foam layer, such as at least one layer of foam 106, The plurality of fragment resistant woven fabric layers includes a first set of fragment resistant woven fabric layers 102a, a second set of fragment resistant woven fabric layers 102b and a third set of fragment resistant woven fabric layers 102c. Accordingly, the ballistic resistant flexible structure 100 is an assembly comprising of various types of ballistic resistant materials.

[0035] The at least one polycarbonate layer 104 is disposed parallel between the first set of fragment resistant woven fabric layers 102a and the second set of fragment resistant woven fabric layers 102b, the at least one foam layer 106 is disposed parallel to the second set of fragment resistant woven fabric layers 102b and the third set of fragment resistant woven fabric layers 102c is disposed parallel to the at least one foam layer 106. In one embodiment of the present invention, outer 04 to 40 layers of the first set of fragment resistant woven fabric layers 102a is followed by 01 to 03 layers of the polycarbonate 104. The polycarbonate layers 104 are followed by 1 to 4 layers of the second set of fragment resistant woven fabric layers 102b. These woven aramid fabric layers 102b are followed by 01 to 12 layers of foam 106 that are again followed by 1 to 4 layers of the third set of fragment resistant woven fabric layers 102c which serve as the irmermost layer. However, the present invention is not limited to any particular sequence and any particular number of layers used.
[0036] In one embodiment of the present invention the woven aramid fabric
layers 102a, 102b and 102c have an areal density in the range of 80-500 gsm. However, the present invention is not limited to any particular areal density of the woven aramid fabric. Further, the assemblies of aramid fabrics are stitched together. More specifically, the stitch is 2-6 cm diagonal quilt stitching. However, the present invention is not limited to any particular method of assembling of the aramid fabrics. Further in one embodiment of the invention, the polycarbonate 104 is a polycarbonate having comparatively high areal density. Furthermore, in one embodiment of the present invention, the polycarbonate may have variable thickness in the range of 0.2mm, 0.25mm, 0.5mm 0.75mm, 1mm and the like. Further, the thickness of foam varies from 01mm to 06mm. However, the present invention is not limited to any particular thickness range/ thickness of the polycarbonate or foam.
[0037] Referring to Figure 2, a ballistic resistant flexible structure 200 is depicted
in accordance with another embodiment of the present invention. The ballistic resistant flexible structure 200 includes a plurality of fragment resistant woven fabric layers, such as a plurality of woven aramid fabric layers , at least one thermoplastic polymer layer, such as at least one layer

of polypropylene 204, and least one foam layer, such as at least one layer of foam 206. The plurality of fragment resistant woven fabric layers includes a first set of fragment resistant woven fabric layers 202a, a second set of fragment resistant woven fabric layers 202b and a third set of fragment resistant woven fabric layers 202c. The ballistic resistant flexible structure 200 is an assembly comprising of various types of ballistic resistant materials.
[0038] The at least one polypropylene layer 204 is disposed parallel between the
first set of fragment resistant woven fabric layers 202a and the second set of fragment resistant woven fabric layers 202b, the at least one foam layer 206 is disposed parallel to the second set of fragment resistant woven fabric layer 202b and the third set of fragment resistant woven fabric layers 202c are disposed parallel to the at least one foam layer 206. In one embodiment of the present invention, outer 04-40 layers of the first set of fragment resistant woven fabric layers 202a is followed by 1 to 8 layers of polypropylene 204. The polypropylene layers 204 are followed by 1 to 4 layers of the second set of woven aramid fabric 202b. These woven aramid fabric layers 202b are followed by 01 to 12 layers of foam 206 that are again followed by 1 to 4 layers of the third set of woven aramid fabrics 202c. However, the present invention is not limited to any particular sequence and any particular number of layers used.
[0039] Referring to Fig. 3, a ballistic resistant flexible structure 300 is depicted in
accordance with yet another embodiment of the present invention. The ballistic resistant flexible structure 300 includes a plurality of fragment resistant aramid fabric layers, such as Unidirectional (UD) aramid fabric layers 302, at least one thermoplastic polymer layer, such as at least one layer of polypropylene 304 and at least one foam layer, such as at least one layer of foam 306. The plurality of fragment resistant aramid fabric layers 302 includes a first set of fragment resistant aramid fabric layers 302a, a second set of fragment resistant aramid fabric layers 302b and a third set of fragment resistant aramid fabric layers 302c, Accordingly, the ballistic resistant flexible structure 300 is an assembly of various types of ballistic resistant material.

[0040] The at least one polypropylene layer 304 is disposed parallel between the
first set of fragment resistant aramid fabric layers 302a and the second set of fragment resistant aramid fabric layers 302b, the at least one foam layer 306 is disposed parallel to the second set of fi-agment resistant aramid fabric layers 302b and the third set of fi-agment resistant aramid fabric layers 302c is disposed parallel to the at least one foam layer 306. In one embodiment of the present invention, the outer 04-40 layers of the first set of fragment resistant UD aramid fabric 302a are followed by 1 to 8 layers of polypropylene 304. The polypropylene layers 304 are followed by 1 to 4 layers of the second set of UD aramid fabric 302b. These 1 to 4 layers of UD aramid fabric 302b are followed by 01 to 12 layers of foam 306. These layers of foam 306 are again followed by 1 to 4 layers of the third set of UD aramid fabrics 302c. However, the present invention is not limited to any particular sequence and any particular number of layers used.
[0041] In one embodiment of the present invention, the areal density of UD
aramid fabric 302 is in the range of 90-300 gsm. However, the present invention is not limited to any particular value of the areal density of the UD aramid fabric 302. Further, the UD aramid fabric 302 may be GA 2010, GN etc. from Honeywell. However, the present invention is not limited to any particular example described. Further, the assemblies of UD aramid fabrics 302 are stitched together. More specifically the stitching is done along the periphery. However, the present invention is not limited to any particular method used for assembling of the UD aramid fabrics 302.
[0042] Referring to Fig. 4, a ballistic resistant flexible structure 400 is depicted in
accordance with yet another embodiment of the present invention. The ballistic resistant flexible structure 400 includes a plurality of thermoplastic polymer layers and at least one layer of foam 406. The at least one foam layer 406 is disposed parallel amongst the plurality of thermoplastic polymer layers. In one embodiment of the present invention, the plurality of thermoplastic polymer layers includes a plurality of polyethylene fabric layers 402 and at least one layer of polypropylene 404. Further, in one embodiment of the present invention, the plurality of polyethylene fabric layers includes a first set of polyethylene fabric layers 402a, a second set of polyethylene fabric layers 402b and a third set of polyethylene fabric layers 402c. Accordingly,

the ballistic resistant flexible structure 400 is an assembly of various types of ballistic resistant materials.
[0043] In one embodiment of the present invention, the at least one polypropylene
layer 404 is disposed parallel to the first set of polyethylene fabric layers 402a, the second set of polyethylene fabric layers 402b is disposed parallel to the at least one layer of polypropylene 404, the at least one foam layer 406 is disposed parallel to the second set of polyethylene fabric layers 402b and the third set of polyethylene fabric layers 402c is disposed parallel to the at least one foam layers 406. More specifically, in one embodiment of the present t invention, the outer 04-40 layers of the first set of polyethylene fabric layers 402a is followed by 1 to 8 layers of polypropylene 404. The polypropylene layer 404 is followed by 1 to 4 layers of second set of polyethylene fabric layers 402b. These layers of Polyethylene fabric 402b are followed by 2 to 12 layers of foam 406 that are again followed by 1 to 4 layers of the third set of Polyethylene fabric layers 402c. However, the present invention is not limited to any particular sequence and any particular number of layers used.
[0044] In one embodiment of the present invention, the areal density of the
Polyethylene fabric 402a, 402b and 402c is in the range of 90-300 gsm. However, the present invention is not limited to any particular areal density of the Polyethylene fabrics. Further, the PE fabrics 402 used may be SB21 from DSM and SA1211 from Honeywell and alike. However, the present invention is not limited to any particular example of the PE fabrics 402. In one embodiment of the present invention, the PE fabrics 402 used is high performance PE fabrics.
[0045] In one embodiment of the present invention, the layers of polypropylene
304 and 404 may be replaced by polycarbonate layers. The polycarbonate layers may be of high areal density. Further, the polycarbonate layers used may have variable thickness viz. 0.2mm, 0.25mm, 0.5mm 0.75mm, 1mm or alike. Further, in one embodiment of the present invention, the thickness of foam varies fi-om 01mm to 06mm. However, the present invention is not limited to any particular areal density of UD aramid fabric or Polyethylene fabric. Similarly, the present invention is not limited to a particular areal density of polycarbonate and thickness of foam.

[0046] Further, in one embodiment of the invention the polypropylene used may
be Teijin Products like LFT AT Flex, LFT AT and the alike or it may be pure fabric, MFT, Laminado or alike. Further the polypropylene layer may be in molded form. Furthermore the polypropylene layer may be composed of 2- 8 layers of polypropylene molded by methods known in prior art.
[0047] Furthermore, in one embodiment of the present invention the thickness of
foam varies from 01mm to 06mm. However, the present invention is not limited to any particular thickness of foam described. Moreover, different kinds of foam such as but not limited to PE foam, EVA foam, EP foam and alike may be used.
[0048] Moreover, in one of the embodiment of the present invention the thickness
of the ballistic resistant flexible structures 100 to 400 may vary from 10mm to 30 mm depending upon the numbers of layer of different ballistic materials used. However, the present invention is not limited to any particular thickness of the ballistic resistant flexible structures 100 to 400. Further, the ballistic resistant flexible structures 100 to 400 may have the trauma or Back Face Signature (BFS) in a range of 8mm to 30mm when tested according to NIJ 0101.04 level III A. However, the present invention is not limited to any particular range of the trauma or Back Face Signature (BFS). This reduced trauma help to reduce the fatal injury to human body. Furthermore it provides the soft cushion effect to the body. More specifically, the ballistic resistant flexible structures 100 to 400 comply with testing standard NIJ 0101.04 up to protection level IIIA. Moreover, in one embodiment of the present invention, the ballistic resistant flexible structures 100 to 400 have an areal density in the range of 3.5 to 5.7kg/m2. However, the present invention is not limited to any particular value of the areal density of the ballistic resistant flexible structures 100 to 400.
[0049] Additionally, the present invention is not limited to any particular number
of layers used for constructing the ballistic resistant flexible structures 100 to 400. The number of layers of different components may be varied depending upon various factors such as mass,

the protection level required and the like. Further each of these layers is adapted to provide ballistic protection property. Further all these layers are stacked together by means of various stacking systems and methods known in the art such as but not limited to stitching and the like. Furthermore, the present invention is not limited to any particular method used for stacking the plurality of layers of the ballistic resistant flexible structure 100 to 400.
[0050] Although, the ballistic resistant flexible structures 100 to 400 as
disclosed in conjunction with Fig. 1, Fig.2, Fig 3 and Fig 4 is described in conjunction with aramid fabrics, polycarbonate and polypropylene sheet, the present invention is not limited to use of these components only. Accordingly, the ballistic resistant flexible structures 100 to 400 of the present invention for facilitating increased protection against trauma or back face signature may also be composed of various other ballistic protection materials such as, high molecular weight polyethylene, high performance nylon fiber and the like known in the prior art.
[0051] Although, Figs 1, Fig 2, Fig 3 and Fig 4 of present invention describes
the ballistic resistant flexible structures 100 to 400 with particular sequencing, the ballistic resistant flexible structures 100 to 400 of the present invention is not limited to the particular sequence described in conjunction with Figs 1 Fig2, Fig 3 and Fig 4.
[0052] Various embodiments of the present invention offer following advantages.
The ballistic resistant flexible structure, as described herein, provides increased protection against trauma or Back Face Signature (BFS). Further, the ballistic resistant flexible structure of the present invention apart from providing increased protection against trauma or Back Face Signature (BFS) provides additional protection against fragments, such as bullets, fragments and the like. Still further, the ballistic resistant flexible structure has comparatively reduced areal density. Moreover, the ballistic resistant flexible structure of the present invention provides increased mobility and combat performance to the law enforcement agencies. Additionally, the ballistic resistant flexible structure is adapted to provide soft cushion effect to a body portion of a user. Also, the ballistic resistant flexible soft structure has comparatively less mass. Moreover, the ballistic resistant flexible structure has a flexible structure. Additionally, the size and shape of

the ballistic resistant flexible structure of the present invention may be easily varied to accommodate different user's size for an appropriate fit and effective protection.
[0053] The foregoing descriptions of specific embodiments of the present
invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

We claim:
1. A ballistic resistant flexible structure comprising:
a plurality of fragment resistant fabric layers comprising a first set of fragment resistant fabric layers, a second set of fragment resistant fabric layers and a third set of fragment resistant fabric layers;
at least one thermoplastic polymer layer; and
at least one foam layer,
wherein said at least one thermoplastic polymer layer is disposed parallel between said first set of fragment resistant fabric layers and said second set of fragment resistant fabric layers, said at least one foam layer is disposed parallel to said second set of fragment resistant fabric layers and said third set of fragment resistant fabric layers are disposed parallel to said at least one foam layer.
2. The ballistic resistant flexible structure as claimed in claim 1, wherein said at least one thermoplastic polymer layer is of polycarbonate.
3. The ballistic resistant flexible structure as claimed in claim 1, wherein said at least one thermoplastic polymer layer is of polypropylene.
4. The ballistic resistant flexible structure as claimed in claim 1, wherein said plurality of fragment resistant fabric layers is composed of woven aramid fabrics.
5. The ballistic resistant flexible structure as claimed in claim 1, wherein said plurality of fragment resistant fabric layers is composed of unidirectional aramid fabrics.

6. The ballistic resistant flexible structure as claimed in claim 1, wherein said first
set of fragment resistant fabric layers comprises about 04 to 40 fragment resistant fabric layers.
7. The ballistic resistant flexible structure as claimed in claim 1, wherein said second set of fragment resistant fabric layers comprises about 01 to 04 fragment resistant fabric layers.
8. The ballistic resistant flexible structure as claimed in claim 1, wherein said third set of fragment resistant fabric layers comprises about 01 to 04 fragment resistant fabric layers.
9. The ballistic resistant flexible structure as claimed in claim 1, wherein the number of foam layers is about 01 to 12.
10. The ballistic resistant flexible structure as claimed in claim 1, wherein the number
of thermoplastic polymer layers is about 01 to 08.
11. The ballistic resistant flexible structure as claimed in claim 1, wherein said at least
one thermoplastic polymer layers has an areal density in the range of 80-500 gsm.
12. A ballistic resistant flexible structure comprising:
a plurality of thermoplastic polymer layers; and
at least one foam layer disposed parallel amongst said plurality of thermoplastic pol}'mer layers.

13. The ballistic resistant flexible structure as claimed in claim 12, wherein said plurality of thermoplastic polymer layers comprises a plurality of polyethylene fabric layers and at least one layer of polypropylene.
14. The ballistic resistant flexible structure as claimed in claim 13, wherein said plurality of polyethylene fabric layers comprises a first set of polyethylene fabric layers, a second set of polyethylene fabric layers and a third set of polyethylene fabric layers.
15. The ballistic resistant flexible structure as claimed in claim 14, wherein said at least one polypropylene layer is disposed parallel to said first set of polyethylene fabric layers, said second set of polyethylene fabric layers is disposed parallel to said at least one layer of polypropylene, said at least one foam layer is disposed parallel to said second set of polyethylene fabric layers and said third set of polyethylene fabric layers is disposed parallel to said at least one foam layer.
16. The ballistic resistant flexible structure as claimed in claim 14, wherein said first set of polyethylene fabric layers comprises 04-40 layers of the polyethylene fabric, said second set of polyethylene fabric layers comprises 01 to 04 layers of the polyethylene fabric and said third set of polyethylene fabric layers comprises 01 to 04 layers.
17. The ballistic resistant flexible structure as claimed in claim 12, wherein said plurality of thermoplastic polymer layers comprises a plurality of polyethylene fabric layers and a plurality of polycarbonate layers.