Note: Descriptions are shown in the official language in which they were submitted.
CA 02313995 2000-07-18
BALLISTIC RESISTANT FABRIC
FIELD OF THE INVENTION
This invention relates to a ballistic resistant fabric, and more particularly
a ballistic
resistant fabric that utilizes poly(p-phenylene-2,6-benzoloisoxazole).
BACKGROUND OF THE INVENTION
Numerous ballistic resistant fibers and woven fabrics have been utilized for
the
construction of ballistic resistant garments. It has been a desire over the
years in the ballistic
garment industry to strive to improve the reliability and stopping capability
of a garment and yet,
not compromise wearability. Undesirable wearability may too often lead to
early removal of the
protective garment or not wearing it at all.
As improved stronger ballistic resistant fibers are developed, less total
weight of the fiber
is needed in producing the ballistic resistant fabric that will maintain the
needed reliability and
stopping capability of a garment. Utilization of these improved fibers result
in less weight and
bulk to the ballistic resistant fabric.
One of these fibers that has been developed in recent years is poly (p-
phenylene-2,
6-benzoloisoxazole) (PBO) or commercially known as Zylon~, a trademark of the
Toyobo Co.,
Ltd., of Osaka, Japan. This fiber is known for its high strength
characteristics however, by the
nature and cost of production of this fiber, the fiber is generally
significantly more costly than
other ballistic resistant fibers. As a result, the fabrics manufactured with
this filer are
traditionally more expensive. Thus, in an era of improving ballistic resistant
fibers that result in
enhancing wearability, increased cost to the user becomes a factor to the
wearability of the
fabric. Accordingly, a reduction in the cost of producing such desirable
fabrics is needed,
however, stopping capability must not be compromised.
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CA 02313995 2000-07-18.
The utilization of PBO fiber in the construction of ballistic resistant fabric
has been
performed and such fabric has been used in the manufacture of ballistic
resistant vests. The
ballistic resistant vests employ PBO fibers in a thirty by thirty, warp and
weft ends per inch in a
plain weave. Emphasis has also been placed on increasing the number of weft
and warp PBO
fibers beyond thirty per inch, disadvantageously requiring increased amounts
of the ballistic
resistant material to be used in producing the costly fabric. In addition, PBO
fibers have been
used in all of the fibers in either the warp or the weft of a woven fabric and
a different type of
fiber material for all of the fibers in either the crossing weft or warp is
used where the PBO fiber
is not located. Disadvantageously, however, this does not provide for a
homogeneous mix of the
fibers and ballistic stopping capabilities, at times, are not readily
improved.
SUMMARY OF THE INVENTION
It is an object of the present invention to address the above referenced needs
by providing
a ballistic resistant woven fabric for use in ballistic resistant protective
products which is cost
efficient and economically advantageous without compromising wearability or
ballistic stopping
capabilities.
An advance is made over the prior art in accordance with the principles of the
invention
wherein a ballistic resistant woven fabric constructed of PBO fibers has a
warp of less than thirty
PBO fibers per inch and a weft of less than thirty PBO fibers per inch. In
different embodiments
various weaves of the ballistic resistant woven fabric may be selectively
employed such as a
plain weave, sateen weave, venetian weave or a corkscrew weave. The weaves of
the various
embodiments may have balanced or imbalanced numbers of fibers per inch and
have twisted
warp and/or weft fibers which preferably range from one-quarter to three
twists per linear inch of
the fiber.
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' In accordance with another embodiment of the present invention, a ballistic
resistant
woven fabric utilized in the construction of ballistic resistant protective
items is provided in
which the woven fabric has a warp with at least two adjacent fibers in which
one fiber is
constructed of a first material and the other fiber is constructed of a second
material. The woven
fabric has a weft having at least two other adjacent fibers with one fiber
constructed of the first
material and the other adjacent fiber constructed of the second material. The
weave may
selectively have a balanced or unbalanced number of fibers per inch in the
warp and weft
directions. Preferably, the fibers in the warp form a pattern with a plurality
of the pattern of
fibers are positioned consecutively in the warp of the fabric and a plurality
of patterns of the
fibers of the weft are positioned consecutively in the weft of the fabric.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing advantageous features of the invention will be explained in
greater detail
and others will be made apparent from the detailed description of the present
invention which is
given reference to the several figures of the drawing, in which:
Fig. 1 is a front plan view of a layer of a plain weave of ballistic resistant
woven fabric
constructed of PBO fibers;
Fig. 2 is a front plan view of a layer of a sateen weave of ballistic
resistant woven fabric
constructed of PBO fibers;
Fig. 3 is a front plan view of a layer of a venetian weave of ballistic
resistant woven
fabric constructed of PBO fibers;
Fig. 4 is a front plan view of a layer of a corkscrew weave of ballistic
resistant woven
fabric constructed of PBO fibers;
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Fig. 5 is a front plan view of a layer of ballistic resistant woven fabric
having adjacent
alternating fibers in the warp and the weft which are constructed of different
ballistic resistant
materials;
Fig. 6 is a front plan view of a layer of ballistic resistant woven fabric
having sets of four
adjacent consecutive fibers with a first set of two fibers constructed of one
material and a second
set of two fibers constructed of a second material; and
Fig. 7 is a front plan view of a layer of ballistic resistant woven fabric
having sets of six
adjacent consecutive fibers with a first set of three adjacent fibers
constructed of one material
and a second set of three adjacent fibers constructed of a second material.
DETAILED DESCRIPTION
Referring to Fig. 1, a sheet of ballistic resistant woven fabric 110 which is
utilized in the
construction of ballistic resistant protective items such as ballistic
resistant garments, helmets,
vehicles and the like is shown having a plain weave. The woven fabric 110 of
Fig. 1 is
constructed of a plurality of fibers of poly(p-phenylene-2,6-benzobisoxazole)
(PBO) material. In
the plain weave 112 arrangement as seen in Fig. 1, both the warp fibers 114
and the weft fibers
116 of the weave are formed of PBO material. PBO is a rigid-rod isotropic
liquid crystal
polymer high performance fiber made by Toyobo Co., Ltd. of Osaka, Japan and is
commonly
sold under the trademark name Zylon~. As seen in Fig. 1, the plain weave 112
of PBO material
preferably is a balanced weave, however an imbalanced weave may selectively be
employed.
The balanced plain weave 112 for the woven fabric 110, of Fig. 1, may employ a
warp
118 of twenty-seven fibers per inch and a weft 120 of twenty-seven fibers per
inch. In
accordance with the present invention, the warp 118 of the ballistic resistant
woven fabric I 10 of
PBO material has less than thirty (30) fibers of PBO material per inch of warp
and the weft 120
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of the woven fabric 110 also has less than thirty (30) fibers of PBO material
per inch of weft.
Preferably, the warp 118 ranges from 23 to 29 fibers of PBO per inch and the
weft 120 also
ranges from 23 to 29 fibers of PBO per inch. The fibers 114, 116 in the warp
118 and in the weft
120 may selectively be twisted. The fibers 114 in the warp 118 which are
twisted have a number
of twists per linear inch which ranges between one-quarter ('/,) and three (3)
twists per linear
inch. Similarly, in embodiments having twisted weft fibers 116, the number of
twists for the
weft fibers range from '/< to 3 twists per linear inch. Twisting of the fibers
provides added
strength to the fabric and can provide greater ease in weaving the fibers
together during
manufacture.
As will be appreciated by those skilled in the art and as seen in Fig. 1, the
plain weave
112 has a warp fiber which passes over a first weft fiber and then passes
under the next adjacent
weft fiber. The warp fiber continues to thereafter alternate passing over and
under consecutive
weft fibers. The next adjacent warp fiber passes under the first weft fiber
and then passes over
the next adjacent weft fiber and, as seen in Fig. 1, continues to alternate
passing under and over
consecutive weft fibers. The plain weave then continues following this
pattern.
V-50 tests of the ballistic resistant fabric of the invention have been
performed against a
control fabric. As will be appreciated by those skilled in the art, V-SO
testing is performed on a
sample of body armor to determine the velocity at which a specific projectile
has a 50%
probability of complete or partial penetration. As set forth in the
Informational Brief on V-50
testing by the National Law Enforcement & Corrections Technology Center, V-SO
testing is
performed by firing a specific projectile at a sample of body armor at a
velocity which has been
determined to be near, but below, the velocity at which the projectile is
expected to penetrate the
armor sample. The velocity at which penetration occurs is experimentally
determined by
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increasing the velocity of successive shots by small increments. A number of
shots is fired at
the sample, and the velocity is adjusted until half of the shots penetrate,
and half do not. The
average velocity from the highest three non-penetrating rounds and the lowest
three penetrating
rounds is the V-50 number for that specific projectile and armor sample.
A control fabric for V-50 testing which was performed was a 30x30 (30 warp
fibers and
30 weft fibers per inch) plain weave of 500 denier PBO material. The
individual plies of the
control fabric had a weight of 3.97 ounces per square yard and had a thickness
of 0.0072 inches
per ply. The control fabric was arranged in a pad having twenty-nine (29)
plies with a total
weight for the V-SO testing at 0.69 pounds per square foot (lbs/ft2). Two V-50
tests were
performed on separate pads at which 9mm 124 grain full metal jacket rounds
were fired. The
threshold velocities for the control pads for the two V-50 tests averaged 1611
feet per second.
Additionally, .357 Magnum 158 grain Steel Jacket High Power (SJHP) rounds were
also fired in
accordance with the V-50 test and had threshold velocities averaging 1582 feet
per second.
A fabric 110 having a 27x27 plain weave (27 warp fiber ends and 27 weft fiber
ends per
inch) of 500 denier PBO was tested against the control fabric. The 27x27 plain
weave 112 of
PBO had a weight of 3.57 ounces per square yard (for an individual ply) and a
thickness of
0.0080 inches per ply. Twenty-eight (28) plies were used for testing the pad.
The plies were
27x27 PBO plain weave fabric with the pad having a weight of 0.69 (lbs/ft2) to
match the control
pad. Two V-50 tests were conducted using 9mm 124 grain full metal jacket
rounds. The V-50
tests using the 27x27 PBO fabric reached threshold velocities averaging 1701
feet per second; a
5.6% improvement over the control fabric. .357 Magnum rounds were fired and
reached
threshold velocities averaging 1675 feet per second; a 5.8% improvement over
the control fabric.
These improved stopping capabilities for the relatively looser weave of PBO
fibers are counter
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intuitive to conventional wisdom and provide the advantage of requiring fewer
layers and thus,
less PBO material to obtain the same stopping capabilities as the control
fabric.
Referring now to Fig. 2, ballistic resistant woven fabric 210 is shown having
a sateen
weave 212 of PBO fibers. A balanced sateen weave 212 of 29 fibers 214 per inch
in the warp
218 and 29 fibers 216 per inch in the weft 220 has been constructed and
tested. Alternatively, an
imbalanced weave of PBO fibers may be utilized. In accordance with one aspect
of the
invention, the sum total of PBO fibers 214 per inch of the warp 218 plus the
PBO fibers 216 per
inch of the weft 220 in the sateen weave 212 is less than fifty-eight (58)
fibers. The warp 218 of
the sateen weave 212 has at least 20 PBO fibers per inch and has no greater
than 29 PBO fibers
per inch. The weft 220 also preferably has at least 20 PBO fibers per inch and
has no greater
than 29 PBO fibers per inch. The PBO fibers 214, 216 in the warp 218 and in
the weft 220 may
selectively be twisted. The PBO fibers 214 in the warp 218 as well as the PBO
fibers 216 in the
weft 220 which are twisted preferably have a number of twists per linear inch
which ranges
between '/, and 3 twists per linear inch.
As seen in Fig. 2, the sateen weave 212 begins with a warp fiber passing over
a first weft
fiber and then passes under the next two adjacent weft fibers. The warp fiber
continues to repeat
thereafter passing over a weft fiber and passing under the next two weft
fibers. As will be
appreciated by those skilled in the art, the next adjacent warp fiber then is
positioned under the
first two weft fibers and then over the following weft fiber and continues to
repeat this pattern.
The third consecutive warp fiber passes under the first weft fiber, over the
next weft fiber and
under the next following weft fiber. The third consecutive warp fiber then
repeats this pattern.
The overall weaving pattern then repeats itself as seen in Fig. 2.
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" V-50 experiments were conducted for the ballistic resistant fabric having a
sateen weave.
A 29x29 sateen weave (29 warp fibers per inch by 29 weft fibers per inch) of
500 denier PBO
material having a weight of 3.80 ounces per square yard (per ply) and a
thickness of 0.0080
inches per ply was tested. The sateen weave of the plies of ballistic
resistant fabric had a soft,
open structure with warp ends crossing four fill ends, then woven under one
pick. These plies or
sheets of the 29x29 sateen weave of PBO material (satin fabric) were arranged
in a pad such that
twenty-six (26) plies were employed in forming the pad which had a total
weight of 0.69
(lbs/ft2) to match the control pad. 9mm 124 grain full metal jacket rounds
were fired at the pad
and a threshold velocity of 1753 feet per second was obtained. V-50 testing
using .357 Magnum
158 grain SJHP rounds were fired at the pad having the 29x29 sateen weave of
PBO material and
a threshold velocity of 1749 feet per second was recorded. The 29x29 warp and
fill sateen
weave of PBO material showed an 8.8% difference over the control fabric
(discussed above) for
the 9mm rounds and a 10.6% difference over the control fabric for the .357
Magnum rounds.
Referring to Fig. 3, ballistic resistant woven fabric 310 is shown having a
venetian weave
312 of PBO fibers. The venetian weave 312 may selectively be a balanced or
unbalanced weave
of PBO fibers. The venetian weave 312 of PBO fibers preferably has at least 20
warp fibers 314
per inch and has no greater than 29 warp fibers per inch. The weft 320 of the
venetian weave
312 also has at least 20 fibers per inch and preferably has no more than 29
weft fibers per inch.
The sum total of fibers 314 per inch of the warp 318 plus the fibers 316 per
inch of the weft 320
in the venetian weave 312 is preferably less than fifty eight (58) fibers. The
PBO fibers, in the
warp 318, the weft 320, or both, of the venetian weave 312 may selectively be
twisted. For the
twisted fibers in the warp 318, the number of twists per linear inch ranges
between '/4 and 3
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twists per linear inch. The twisted PBO fibers in the weft 320 also range
between '/4 and 3 twists
per linear inch.
As seen in Fig. 3, the venetian weave has a first warp fiber passing over
three weft fibers
and under the next two weft fibers, with the first warp fiber repeating the
over three/under two
pattern thereafter. As will be appreciated by those skilled in the art, the
next or second warp
fiber for the venetian weave passes over the first weft fiber, then under the
next two weft fibers
and over the following two weft fibers and repeats this pattern thereafter.
The third warp fiber
begins under the first weft fiber and over the next three weft fibers and
under the following weft
fiber, repeating thereafter. The fourth warp fiber begins by passing over the
first two weft fibers,
under the next two weft fibers and over the following weft fiber and
thereafter repeating the
pattern. Finally, a fifth adjacent warp fiber passes under the first two weft
fibers and then over
the next three weft fibers, repeating the pattern thereafter. The overall
venetian weaving pattern
then repeats itself throughout the fabric.
V-SO experiments were conducted for the ballistic resistant fabric having a
venetian
weave. A 29x29 venetian weave (29 warp fiber ends per inch by 29 weft fiber
ends per inch) of
500 denier PBO material having a weight of 3.67 ounces per yard (per ply) and
a thickness of
0.0100 inches per ply was tested. The venetian weave of the ballistic
resistant fabric tested had a
soft, open structure with warp ends moved every other pick alternately. The
plies or sheets of
the 29x29 venetian weave of PBO material were arranged in a pad for the V-SO
testing. Twenty-
seven (27) plies of the 29x29 venetian weave of PBO material were used in
forming the test pad
such that the test pad had a weight of 0.69 lbs/ft2 to match the weight of the
control pad
(discussed above). 9mm 124 grain full metal jacket rounds were fired at the
pad having the plies
of 29x29 venetian weave of PBO material and a threshold velocity of 1728 feet
per second was
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reco~'ded. V-50 testing for the pad using the venetian plies was performed at
which .357
magnum 158 grain SJHP rounds were fired and a threshold velocity of 1792 feet
per second was
recorded. The 29x29 warp and fill venetian weave showed a 7.3% difference over
the control
fabric (discussed above) for the 9mm rounds and a 13.3% difference over the
control fabric for
the .357 Magnum rounds.
Refernng now to Fig. 4, ballistic resistant woven fabric 410 having a
corkscrew weave
412 of PBO fibers is shown. The corkscrew weave 412 of Fig. 4 is preferably a
balanced weave
having 27 PBO fibers 414 per inch in the warp 418 and 27 PBO fibers 416 per
inch in the weft
420. An imbalanced weave may alternatively be employed which has less than 30
warp fibers
per inch and less than 30 weft fibers per inch in the corkscrew weave. The
warp 418 of the
corkscrew weave 412 preferably ranges from 23-29 fibers 414 per inch and the
weft 420 of the
corkscrew weave also preferably ranges from 23-29 fibers 416 per inch. As seen
in Fig. 4, the
fibers 414, 416 of PBO material are arranged in a five end weft corkscrew
weave 412. Other
corkscrew weaves which may selectively be employed for the woven ballistic
resistant fabric
410 of PBO material include: seven end weft corkscrew weave; seven end warp
corkscrew
weave; nine end weft corkscrew weave; nine end warp corkscrew weave; and
thirteen shaft
corkscrew weave. The fibers 414 in the warp direction 418 and the fibers 416
in the weft 420
direction may selectively be twisted. The weft fibers 416 and the warp fibers
414 which are
twisted in the corkscrew weave 412 have a range in the number of twists per
linear inch which
ranges between '/4 and 3 twists per linear inch.
The five end weft corkscrew weave of Fig. 4 begins with a first warp fiber
passing over
two first weft fibers, under the next weft fiber, over the following weft
fiber and then under the
fifth weft fiber, thereafter repeating. The second warp fiber passes under the
first weft fiber,
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over the second, under the third and over the fourth and fifth weft fibers,
thereafter repeating.
The third warp fiber passes under the first weft fiber, over the second and
third, under the fourth
and over the fifth weft fiber, thereafter repeating. The fourth warp fiber
passes over the first weft
fiber, under the second, over the third under the fourth and over the fifth
weft fiber, thereafter
repeating. Finally, the fifth warp fiber passes over the first weft fiber,
under the second, over the
third and fourth weft fibers and under the fifth weft fiber, thereafter
repeating. As will be
appreciated by those in the art, this overall weaving pattern then repeats
itself for the five end
weft corkscrew weave.
Referring now to Fig. 5, a ply of ballistic resistant woven fabric 510 for
utilization in the
construction of ballistic resistant protective items is shown having
alternating fibers in the warp
518 and in the weft 520 which are constructed of different materials. The warp
518 of the
ballistic resistant woven fabric 510 has two adjacent fibers 514A, 514B in
which one fiber 514A
is constructed of a first material (preferably PBO) and another fiber 514B is
constructed of a
second material. The weft 520 of the ballistic resistant woven fabric 510 has
at least two other
adjacent fibers 516A, 516B in which one fiber 516A is constructed of the first
material (such as
(PBO) and the other fiber 516B adjacent to the one fiber 516A in the weft 520
is constructed of
the second material. The two different types of fiber materials employed may
have different
deniers. It is preferred that the denier of one of the types of fibers of one
material and the denier
of the other type for the other material have a ratio which does not exceed
2.0 with the larger
denier positioned in the numerator and the smaller denier positioned in the
denominator. A ratio
of I .25 or less is highly desirable.
As noted above, preferably the first material which is used in alternating
fashion is PBO
having a denier within the range of 200 to 830 denier. The second material may
selectively be
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either microfilament poly(paraphenylene-terephthalamide) (microfilament PPP-T)
which is
commonly known under the trademark name Twaron~ sold by AKZO NOBEL, Inc. or
poly(paraphenylene-terephthalamide) (PPP-T) which is commonly known under the
trademark
names Kevlar~ or Protera~ which are sold by E.I. duPont de Nemours and Company
of
Wilmington, Delaware. Microfilament PPP-T (or Twaron~) is a high tensile
strength aramid
microfilament fiber. The microfilament PPP-T material used in fibers 514B,
516B preferably
has a denier which ranges from 200 to 830 denier. The PPP-T (Kevlar~ or
Protera~) which
may be suitably employed as the material in fibers 514B, 516B also preferably
range in denier
from 200-830 denier.
As seen in Fig. S, the ballistic resistant woven fabric 510 has a plain weave
512 which is
also a balanced weave. Alternatively, an unbalanced plain weave may be
employed. The
number of fibers 514A, 514B of the warp 518 ranges from 23 to 32 fibers per
inch and the
number of fibers 516A, S 16B of the weft 520 also ranges from 23 to 32 fibers
per inch. One or
both of the warp fibers 514A, S 14B may selectively be twisted in which the
number of twists in
the warp fiber 514A, S 14B range from one-half of a revolution per linear inch
to six revolutions
per linear inch in the fiber. One or both of the adjacent weft fibers 516A,
516B may also
selectively be twisted with the number of twists in the weft fibers) 516A, S
16B ranging from
one-half of a revolution per linear inch to six revolutions per linear inch of
the fiber.
Still referring to Fig. 5, the two adjacent fibers 514A, S 14B in the warp 518
form a
pattern of fibers in which the adjacent fibers are formed of different
materials and alternate
consecutively. As seen in Fig. 5, the ballistic resistant woven fabric 510 has
a plurality of
patterns of adjacent pairs of fibers 514A, 514B positioned consecutively in
the warp 518 in
which one of the warp fibers 514A is formed of one material and the other warp
fiber 514B is
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formed of another material. The adjacent fibers 516A, 516B in the weft 520
from another
pattern comprised of a pair of adjacent fibers formed of different materials.
The plain weave 512
of the ballistic resistant woven fabric 510 has a plurality of other patterns
of adjacent weft fibers
S 16A, 516B positioned consecutively in the weft in which one of the weft
fibers 516A is formed
of one material and the other weft 516B is formed of another material. In one
approach, one of
the alternating warp fibers 514A is constructed of PBO and the other fiber
514B in the adjacent
pair of fibers in the warp 518 is constructed of microfilament PPP-T; the one
weft fiber 516A is
also constructed of PBO and the other adjacent weft fiber 516B is also
constructed of
microfilament PPP-T. In an alternative approach, the one material used for the
one type of warp
fibers 514A and the one type of weft fibers 516A is PBO and the other or
second material which
is used to construct the other type of warp fiber 514B and the other type of
weft fiber PPP-T
(Kevlar~/Protera~ material.)
A fabric having a 29 x 29 plain weave (29 warp fibers and 29 weft fibers per
inch) having
alternating warp fibers and weft fibers of PBO material and PPP-T (Protera~ )
material was
subjected to V-50 testing. The fabric tested had the consecutive alternating
warp fibers and weft
fibers as described in the arrangement of Fig. 5 with PBO being the first type
of material and
PPP-T (Protera~ ) being the second type of material used for the fibers. In
this arrangement,
because PPP-T material was also used in the weave, the amount of PBO used per
ply was
reduced by 44% over the control fabric (described above) having a 30 x 30
weave of all PBO
material. An individual ply (also called layer or sheet) of the fabric tested
had a weight of 3.42
ounces per square yard and a thickness of 0.0075 inch. Twenty-nine (29) plies
were used and
layered to form a pad for the V-50 testing. The pad having the twenty-nine 29
x 29
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PBO~/Protera~ alternate fiber weave plies had a thickness of 0.22 inches and a
weight of 0.69
lbs/ft2 to match the control pad of 30 x 30 PBO material plies, and described
above.
Two V-50 tests were conducted using 9mm 124 grain full metal jacket rounds.
The 29 x
29 plain weave of alternating PBO and Protera~ fibers in the warp and the weft
reached
threshold velocities averaging 1,553 feet per second; only a 3.6% difference
from the control
fabric. .357 Magnum rounds were fired at the pad having plies of alternating
PBO and PPP-T
(Protera~ ) warp and weft fibers in accordance with V-SO test criteria with
threshold velocities
being reached which averaged 1,512 feet per second; only a 4.5% difference
from the control
fabric. Therefore, the V-SO velocity threshold was reduced by only
approximately 4%, but the
amount of PBO material employed in each ply was significantly reduced by
approximately 44%
in the alternate fiber arrangement of Fig. 5 for a 29 x 29 plain weave of PBO
and PPP-T
(Protera~ ).
Although Fig. 5 illustrates a plain weave, other weaves such as sateen weaves,
venetian
weaves and corkscrew weaves are also selectively employed in the ballistic
resistant woven
fabric embodiment having warp fibers and weft fibers of two different types of
materials which
consecutively alternate between fibers of the weave. For the sateen, venetian
and corkscrew
weave patterns, the PBO fiber material, microfilament PPP-T fiber material,
and PPP-T fiber
material preferably all are fibers which have deniers which fall within the
range of 200 to 830
denier. The sateen, venetian, and corkscrew weave having the alternating fiber
material
arrangement of Fig. 5 may be balanced or imbalanced weaves. For the sateen and
venetian
weaves, the number of fibers of the warp ranges from 20-29 warp fiber ends per
inch and the
number of weft fibers ranges from 20-29 weft fiber ends per inch. For the
sateen weave and
venetian weave embodiments, the sum total of fiber ends in one inch of the
warp plus an inch of
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the weft is less than fifty-eight (58). For the corkscrew weave, the number of
fibers of the warp
ranges from 23 to 29 fibers per inch and the number of fibers of the weft also
ranges from 23 to
29 fibers per inch. The fibers 514A, S 14B, S 16A, 516B for the sateen,
venetian and corkscrew
weave arrangements may selectively be twisted with the number of twists
ranging from one-half
to six revolutions per linear inch for the fibers.
The pattern of consecutively alternating warp and weft fibers of two different
material
types as seen in Fig. 5 may also be applied to sateen, venetian and corkscrew
weave patterns.
Ballistic resistant woven fabric employing sateen, venetian or corkscrew
weaves will also have a
plurality of patterns of adjacent pairs of fibers 514A, 514B positioned
consecutively in the warp
518 in which one of the warp fibers 514A is formed of one fiber material (such
as PBO) and the
other warp fiber 514B is formed of another fiber material (such as
microfilament PPP-T or
PPP-T). Adjacent fibers 516A, 516B in the weft for sateen, venetian and
corkscrew weaves also
form a pattern comprised of a pair of adjacent fibers with each fiber formed
of different
materials. For instance, weft fiber 516A being constructed of PBO material and
adjacent weft
fiber S 16B being constructed of microfilament PPP-T (Twaron~) or PPP-T
(Kevlar~/Protera~).
Similar to the plain weave of Fig. S, alternative sateen, venetian and
corkscrew weaves of the
ballistic resistant woven fabric 510 also employ multiple patterns of adjacent
weft fibers 516A,
516B which are positioned consecutively with one of the weft fibers 516A
preferably being
formed of PBO and the other weft fiber 516B preferably being formed of
microfilament PPP-T
(Twaron~) or PPP-T (Kevlar~/Protera~).
Referring now to Fig. 6, a layer of ballistic resistant woven fabric 610
having sets of four
adjacent consecutive fibers in both the warp direction 618 and the weft
direction 620 is shown.
A pattern of four adjacent consecutive fibers in the warp 618 is seen in Fig.
6 with a first set of
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two adjacent warp fibers 614A being constructed of a first type of material
and a second set of
two adjacent warp fibers 614B being constructed of a second type of material.
Also seen in
Fig. 6 is a pattern of four adjacent consecutive fibers in the weft 620 having
a first set of two
adjacent weft fibers 616A being constructed of the first type of material and
the second set of
two adjacent weft fibers 616B being constructed of the second type of
material. Various types of
high strength fiber materials may be employed for the fibers 614A, 614B, 616A,
616B in the
plain weave 612 arrangement of Fig. 6. In one approach, the first set (or
pair) of two adjacent
warp fibers 614A in the pattern in the warp 618 are constructed of PBO and the
second set (or
pair) of two adjacent warp fibers 614B are constructed of microfilament PPP-T
(Twaron~). The
first set of two adjacent weft fibers 616A are also constructed of PBO and the
second set of two
adjacent weft fibers 616B are also made from microfilament PPP-T (Twaron~)
material. PPP-T
(Kevlar~/Protera~) may also selectively be employed as the second type of
material such that
the first pair of adjacent warp fibers 614A in the pattern in the warp 618 are
constructed of PBO
and the second set of two adjacent warp fibers are constructed of PPP-T
(Kevlar~/Protera~)
material.
Fig. 6 illustrates a plain weave 612 formed of a plurality pairs of warp
fibers 614A, 614B
and weft fibers 616A, 616B in which the pairs of fibers are consecutively
alternating between
two different types of fiber materials. The ballistic resistant woven fabric
610 having alternating
pairs of fibers as seen in Fig. 6 may also selectively employ a sateen weave,
venetian weave or
corkscrew weave such as those shown and described with reference to Figs. 2, 3
and 4. The
PBO fiber material, microfilament PPP-T fiber material, and PPP-T fiber
material in the various
weave patterns all preferably have deniers which range between 200 and 830
denier. The weave
patterns may be balanced or imbalanced. The fibers 614A, 614B, 616A, 616B for
the weave
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patteg-ns (plain, sateen, venetian, corkscrew) in the embodiment of Fig. 6,
may selectively be
twisted with the number of twists ranging from one-half to six revolutions per
linear inch for the
fibers. The arrangement of four adjacent consecutive fibers in both the warp
and the weft with
one pair of fibers being formed of one type of high strength fiber material
and the other pair
being formed of another type of high strength fiber material is also employed
in sateen, venetian
and corkscrew weave patterns. In these alternative arrangements, the first
pair of warp fibers in
a pattern of four consecutive fibers in the warp for a sateen weave, venetian
weave or corkscrew
weave are constructed of PBO and the second pair of warp fibers are
selectively constructed of
microfilament PPP-T material or PPP-T material. The first pair of weft fibers
in the sateen,
venetian and corkscrew weaves are also constructed of PBO and the second pair
of weft fibers
are preferably formed of either microfilament PPP-T material or PPP-T
material.
Referring now to Fig. 7, a layer of ballistic resistant woven fabric 710
having sets of six
adjacent consecutive fibers with three consecutive fibers being formed of one
material and three
other consecutive fibers being formed of another material in the weave in both
the warp direction
718 and the weft direction 720 is shown. A pattern of six adjacent consecutive
fibers in the warp
718 is seen in Fig. 7 with a first set of three adjacent warp fibers 714A
being constructed of a
first type of material and a second set of three adjacent warp fibers 714B
being constructed of a
second type of material. Also seen in Fig. 7 is a pattern of six adjacent
consecutive fibers in the
weft 720 having a first set of three adjacent weft fibers 716A being
constructed of the first type
of material and the second set of three adjacent weft fibers 716B being
constructed of the second
type of material. Various types of high strength fiber materials may be
employed for the fibers
714A, 714B, 716A, 716B in the plain weave 712 arrangement of Fig. 7. In one
approach, the
first set of three adjacent warp fibers 714A in the pattern in the warp 718
are constructed of PBO
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' and the second set of three adjacent warp fibers 714B are constructed of
microfilament PPP-T
(Twaron~). The first set of three adjacent weft fibers 716A are also
constructed of PBO and the
second set of three adjacent weft fibers 7168 are also made from microfilament
PPP-T
(Twaron~) material. PPP-T (Kevlar~/Protera~) may also selectively be employed
as the
second type of material such that the first set of three adjacent warp fibers
714A in the pattern in
the warp 718 are constructed of PBO and the second set of three adjacent warp
fibers are
constructed of PPP-T (Kevlar~/Protera~) material.
Fig. 7 illustrates a plain weave 712 formed of a plurality of individual sets
of three warp
fibers 714A, 7148 and three weft fibers 716A, 7168 in which the sets of three
fibers are
consecutively alternating between two different types of fiber materials. The
ballistic resistant
woven fabric 710 having alternating sets of three fibers as seen in Fig. 7 may
also selectively
employ a sateen weave, venetian weave or corkscrew weave such as those shown
and described
with reference to Figs. 2, 3 and 4. The PBO fiber material, microfilament PPP-
T fiber material,
and PPP-T fiber material in the various weave patterns all preferably have
deniers which range
between 200 and 830 denier. The weave patterns may be balanced or imbalanced.
The fibers
714A, 7148, 716A, 7168 for the weave patterns (plain, sateen, venetian,
corkscrew), in the
embodiment of Fig. 7, may selectively be twisted with the number of twists
ranging from one-
half to six revolutions per linear inch for the fibers. The arrangement of six
adjacent consecutive
fibers in both the warp and the weft with one set of three fibers being formed
of one type of high
strength fiber material and the other set of three fibers being formed of
another type of high
strength fiber material is also employed in sateen, venetian and corkscrew
weave patterns. In
these alternative arrangements, the first set of three consecutive warp fibers
in the pattern of six
consecutive fibers in the warp for a sateen weave, venetian weave or corkscrew
weave are
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constructed of PBO and the second set of three consecutive warp fibers are
selectively
constructed of microfilament PPP-T material or PPP-T material. The first set
of three
consecutive weft fibers in the sateen, venetian and corkscrew weaves are also
constructed of
PBO and the second set of three consecutive weft fibers are preferably formed
of either
microfilament PPP-T material or PPP-T material.
While a detailed description of the present invention has been given, it
should be
appreciated that many variations can be made thereto without departing from
the scope of the
invention as set forth in the appended claims.
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