Flexible composites having flexing rigid panels and articles fabricated from same

A flexible article of manufacture especially suitable for use as a ballistic resistant body armor which comprises at least one substrate, said layers being a fibrous layer, and at least one layer having a plurality of bodies sewn to at least one surface of said substrate layer, said bodies having one or more flexible seams which allow portions of said body to flex along said seam.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to flexible composites and to articles fabricated 
therefrom. A more preferred aspect of this invention relates to flexible 
composites and articles having improved penetration resistance. 
2. Prior Art 
Since the beginning of recorded history, a combination of rigid plates or 
panels affixed to a flexible backing, usually fabric or leather, has been 
used extensively as body armor in diverse areas of the world. (Charles 
Ffoulkes, Armour and Weapons Oxford at the Clarendar Press, 1909; H. 
Russell Ribinson, Armour, London: Hebert Jenkins, 1967; A. M. Snodgrass, 
Arms and Armour of the Greeks, Cornell University Press, Ithaca, New York, 
1967; Vesey Norman, Arms and Armor. G. P. Putnam's Sons, New York and 
Claude Blair, European Armour, The McMillan Company, New York, 1959. 
During the 14th century a cloth or leather garment lined with metal 
plates, known as a coat of plates, was the most widely used type of body 
defence. It appears that the plates were rectangular in shape and their 
arrangement prevented draping of the armor or flexing on the bias. Almost 
certainly, this armor limited the mobility of the wearer. A development 
from the coat of plates was the brigandine which remained in general use 
until the 17th century. In the 15th century and later the brigandine 
consisted of a coat of plates made of small lames which could work over 
each other, thus producing a flexible protection. A variant of the 
brigandine, the jack, (15th century) consisted of many small plates of 
iron or horn secured between layers of canvass by a trellis-work of 
stitches. A variant of the jack was the "pennyplate coat" and was 
constructed from small overlapping iron discs with each disc riveted to a 
canvas backing. (See Claude Blair, European Armour, The MacMillan Company, 
New York 1959). 
Roy C. Laible, Ballistic Materials and Penetration Mechanics, Elsevier 
Scientific Publishing Co. Amsterdam Oxford-New York, 1980 describes an 
infantry vest utilizing 149 titanium plates attached to four layers of 
nylon ballistic fabric backing. The plates overlapped and incorporated 
three slits to allow them to slide, thus providing flexibility. The plates 
were rectangular or square in shape and appear to be curved in plane. 
U.S. Pat. No. 4,559,251 describes bullet-proof assemblies, utilizing hinged 
plates but such assemblies utilize relatively large roughly rectangular 
shaped panels. Such an approach is unlikely to lead to flexibility 
required for an infantry vest. U.S. Pat. No. 4,559,251 describes a 
material for protective clothing based on an assembly of hexagonal rigid 
plates. Although such a construction is an improvement over a single rigid 
panel it appears that the structure will have inherent limitations in 
flexibility, contrary to claims in the patent, which would limit its 
usefulness as infantry body armor. 
U.S. Pat. No. 4,483,020 describes a ballistic vest which incorporates 
essentially square plates which interlock when flexed inward. It is 
claimed that such an arrangement reduces blunt trauma. A similar vest is 
disclosed in U.S. Pat. No. 4,660,223 which incorporates multiple titanium 
panels with each titanium panel bonded to aramid fabric. The panels are 
arranged in overlapping and abutting relationship but not connected to 
each other except by overlying and underlying felted material. In this 
disclosure all panels appear to be based on square or rectangular 
considerations. 
A design for body armor has been disclosed in U.S. Pat. No. 4,535,478 in 
which modular panels have been incorporated into a carrier garment. No 
unusual geometric consideration were disclosed. 
Multiple plate body armor has been disclosed in U.S. Pat. No. 4,680,812 
which allows flexibility but protects the body from hyper-extension, thus 
protecting against spinal injury. 
Flexible body armor has been disclosed U.S. Pat. No. 3,894,472 which has a 
central support sheet with the plates arranged in a checkerboard pattern. 
The pattern of the plates on one face are the reverse of the pattern on 
the opposite face. This approach claims complete coverage by rigid plates, 
coupled with appropriate flexibility. 
An infantry body armor system has been disclosed in U.S. Pat. No. 3,557,384 
which provides protection against both fragments and small arms fire. This 
system describes the use of a single plate on the front of the torso and a 
single plate on the back of the torso to provide protection against small 
arms fire and illustrates that relatively large plates may be utilized on 
a limited and specific portions of the torso. 
A complex body armor system has been disclosed in U.S. Pat. No. 3,577,836 
which incorporates multiple Telflon discs which are circular when viewed 
from the front but are elliptical in cross-section. It is claimed that the 
low coefficient of friction facilitates the deflection of projectiles and 
the elliptical cross-section minimizes the number of projectiles which can 
impact normal to the disc surface. 
Ballistic articles such as bulletproof vests, helmets, structural members 
of helicopters and other military equipment, vehicle panels, briefcases, 
raincoats and umbrellas containing high strength fibers are known. Fibers 
conventionally used include aramid fibers such as poly(phenylenediamine 
terephthalamide), graphite fibers, nylon fibers, ceramic fibers, glass 
fibers and the like. For many applications, such as vests or parts of 
vests, the fibers are used in a woven or knitted fabric. For many of the 
applications, the fibers are encapsulated or embedded in a matrix 
material. 
U.S. Pat. Nos. 4,623,574 and 4,748,064 disclose a simple composite 
structure comprising high strength fibers embedded in an elastomeric 
matrix. The simple composite structure exhibits outstanding ballistic 
protection as compared to simple composites utilizing rigid matrices, the 
results of which are disclosed in the patents. Particularly effective are 
simple composites employing ultra-high molecular weight polyethylene and 
polypropylene such as disclosed in U.S. Pat. No. 4,413,110. 
U.S. Pat. Nos. 4,737,402 and 4,613,535 disclose complex rigid composite 
articles having improved impact resistance which comprise a network of 
high strength fibers such as the ultra-high molecular weight polyethylene 
and polypropylene disclosed in U.S. Pat. No. 4,413,110 embedded in an 
elastomeric matrix material and at least one additional rigid layer on a 
major surface of the fibers in the matrix. It is disclosed that the 
composites have improved resistance to environmental hazards, improved 
impact resistance and are unexpectedly effective as ballistic resistant 
articles such as armor. 
U.S. Pat. No. 4,650,710 discloses a flexible article of manufacture 
comprising a plurality of first flexible layers arranged in a first 
portion of the article, each of said first layers consisting essentially 
of fibers having a tensile modulus of at least about 300 g/denier and a 
tenacity of at least about 15 g/denier and a tenacity of at least about 15 
g/denier and a plurality of a second flexible layers arranged in a second 
portion of said article, each of said second flexible layers comprising 
fibers, the resistance to displacement of fibers in each of said second 
flexible layers being greater than the resistance to displacement in each 
of said first flexible layers. 
Other ballistic resistant articles are described in U.S Pat. Nos. 
4,916,000; 4,403,012, 4,457,985; 4,737,401; 4,543,286; 4,563,392 and 
4,501,856. 
SUMMARY OF THE INVENTION 
The present invention relates to flexible composites and to flexible 
articles of manufacture fabricated totally or partially therefrom. More 
particularly this invention provides a flexible composite comprising at 
least one flexible substrate having a plurality of planar bodies affixed 
to all or a portion of a major surface of said substrate layer, said 
bodies having one or more flexible seams which allow one or more portions 
of said bodies to flex along said seam. 
Another aspect of this invention is an article of manufacture fabricated 
totally or in part from the composite of this invention. 
Several advantages flow from this invention. For example, the composite of 
this invention provides a high degree of flexibility in a composite having 
rigid portions. In those embodiments of the invention where the planar 
bodies are made of a penetration resistant material and the composite is 
intended to provide penetration resistance, a high degree of coverage is 
provided. Moreover, the composite and articles exhibit relatively improved 
penetration resistance as compared to fibrous composites of the same areal 
density without unduly affecting the flexibility of the composite or 
article adversely. Moreover, the composite and article of this invention 
suffer minimal loss in puncture resistance when wet as compared to 
conventional puncture resistant composites and articles. Through use of 
this invention, relatively higher denier yarn can be employed in the 
manufacture of the composites and articles of this invention without 
unduly affecting the penetration resistance of the composite or article. 
Flexible article and articles of this invention can incorporate rigid 
plates designed for specific protection. Composites, metal ceramics and 
the like can be utilized as such plates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
The preferred invention will be better understood by those of skill in the 
art by reference to the above figures. The preferred embodiments of this 
invention illustrated in the figures are not intended to be exhaustive or 
to limit the invention to the precise form disclosed. It is chosen to 
describe or to best explain the principles of the invention and its 
application and practical use to thereby enable others skilled in the art 
to best utilize the invention. 
In its broadest aspects, the invention is directed to a multilayered 
article of manufacture comprising at least one flexible substrate having a 
plurality of metal bodies affixed to a surface thereof. 
In general, the flexibility of the composite, of the present invention can 
be demonstrated by Drape Test 1. In this test, a 30 cm square sample of 
the composite is clamped horizontally along one side edge with an overhang 
of 20 cm as shown in FIG. 24, and the amount of drape of the composite 
(the amount of drape being measured by the distance between the level of 
the clamped side edge and the opposite edge) is measured. Composite panels 
were laid onto a flat surface with a portion of the panel overhanging a 
straight edge as shown in FIG. 24 (sideview(A). The initial test is 
carried out with panel sides parallel to the edge and designated 0 
degrees. The ratio of drop of the unsupported side, h, to the distance of 
overhang, 1, is taken as a measure of the flexibility. The composite panel 
is rotated through various angles, and the flexibility measured in a 
similar manner. (The relationship of panel orientation to angle 
designation is shown in FIG. 24 top view (B)). For flexible composites of 
this invention, the amount of drape is ordinarily at least about 8 cm, 
preferably at least about 10 cm, more preferably at least about 13 cm and 
most preferably at least about 17 cm. 
In the preferred embodiments of the invention, the flexibility of the 
composite is determined by Drape Test 2. In this test, composite panels 
were draped around a cylinder (outer diameter(OD)=4 inches (10.2 cm) and 
affixed with rubber bands as shown in FIG. 25 (side view and end view). 
The ratio of the drop to the overhang was taken as a measure of 
flexibility. (See FIG. 25.) This test was used to supplement Drape Test 1 
because it was noted that flexibility after flexing in one plane varied 
markedly with different panels. 
In the more preferred embodiments of the invention, the flexibility of the 
composite is determined by Drape Test 3. In this drape test, the 
flexibility of the composite is judged in three different directions by 
determining if the composite can be wrapped around a cylinder having an 
outside diameter of 3 inches (7.6 cm). The zero degree direction was 
designated for the cylinder length parallel to the panel side length. 
Other directions were designated by the amount of rotation from this 
configuration. 
In the preferred embodiments of the invention, the composite exhibits 
penetration resistance when said article is impacted by a threat without 
adversely affecting the flexibility of the composite to an undue extent. 
As used herein, the "penetration resistance" of the composite is the 
resistance to penetration by a designated threat, as for example, a 
bullet, an ice pick, a knife or the like. The penetration resistance can 
be expressed as the ratio of peak force (F) for designated threat 
(projectile, velocity, and other threat parameters known to those of skill 
in the art to affect peak force) divided by the areal density (ADT) of the 
target. As used herein, the "peak force", is the maximum force exerted by 
a threat to penetrate a designated target using a model 1331 high speed 
Instron Tester having an impact velocity of about 12 ft/sec (3.66 m/sec) 
and where the target strike face area has a diameter of 3 in.(7.6 cm) ; 
and as used herein, the "areal density" or "ADT" is the ratio of total 
target weight to the area of the target strike face. 
Referring to FIGS. 1, 2 and 3, the numeral 10 indicates a ballistic 
resistant article 10, which in the preferred embodiments of the invention 
is ballistic resistant body armor. As depicted in FIG. 3, article 10 is 
comprised of one or more composite layers 12. At least one layer 12 
comprises one or more substrate layers 14. As depicted in FIG. 3, article 
10 is comprised of three layers 12a to 12c. Layers 12a include two layers 
14a and 14b, layer 12b includes nine layers 14a' and 14i' and layer 12c 
includes two layers 14a" and 14b". However, the number of layers 12 and 
substrate layers 14 included in article 10 may vary widely, provided that 
at least two layers are present. In general, the number of layers in any 
embodiment will vary depending on the degree of penetration resistance and 
flexibility desired. The number of layers 12 and substrate layers 14 is 
preferably from 2 to about 70, more preferably from about 5 to about 60 
and most preferably from about 20 to about 50. 
As shown in FIGS. 1, 2, 3 and 4 layer 12 is formed of one or more substrate 
layers 14 secured together by horizontal securing means 18 and vertical 
securing means 20. In the illustrative embodiments of the invention 
depicted in the figures securing means is stitching; however, any 
conventional securing means may be used including but not limited to 
bolts, rivets, adhesive, staples, stitches, and the like. While in the 
embodiment of the figures all substrate layers 14 forming a fibrous layers 
12 are secured together, it is contemplated that the number of layers 14 
secured together may be as few as two, or any number of layers 14 in 
article 10 in any combination. In the preferred embodiments of the 
invention where the number of layers 14 is more than about 20, all the 
layers are not secured together. In these embodiments, from about 2 to 
about 20 layers, preferably from 2 to about 12 layers, more preferably 
from about 2 to about 10 layers and most preferably from about 2 to about 
8 are secured together forming a plurality of packets (not depicted). 
These packets forming various fibrous layers 12 may in turn be secured 
together by a conventional securing means as described above. 
In the preferred embodiments of the invention depicted in FIGS. 1 and 2, 
stitches 18 and 20 are utilized to secure substrate layers 12. The type of 
stitching employed may vary widely. Stitching and sewing methods such as 
lock stitching, chain stitching, zig-zag stitching and the like are 
illustrative of the type of stitching for use in this invention. An 
important feature of this invention is the tensile properties of the fiber 
used in stitching means 14 and 16. It has been found that a relatively 
high modulus (equal to or greater than about 200 grams/denier) and a 
relatively high tenacity (equal to or greater than about 5 grams/denier) 
fiber is essential for the beneficial effects of the invention. All 
tensile properties are evaluated by pulling a 10 in (25.4 cm) fiber length 
clamped in barrel clamps at a rate of 10 in/min (25.4 cm/min) on an 
Instron Tensile Tester. In the preferred embodiments of the invention, the 
tensile modulus is from about 400 to about 3000 grams/denier and the 
tenacity is from about 20 to about 50 grams/denier, more preferably the 
tensile modulus is from about 1000 to about 3000 grams/denier and the 
tenacity is from about 25 to about 50 grams/denier and most preferably the 
tensile modulus is from about 1500 to about 3000 grams/denier and the 
tenacity is from about 30 to about 50 grams/denier. 
Useful threads and fibers may vary widely and will be described in more 
detail herein below in the discussion of fiber for use in the fabrication 
of fibrous layers 12. However, the thread or fiber used in stitching means 
18 and 20 is preferably an aramid fiber or thread (as for example Kevlar 
29, 49, 129 and 149 aramid fibers), an extended chain polyethylene thread 
or fiber (as for example Spectra 900 and Spectra 1000 polyethylene fibers) 
or a mixture thereof. 
The areal density of substrate layer(s) 14 may vary widely, and will depend 
on a number of factors known to those of skill in the art as for example 
the diameter of the threat, and the like. For ballistic body armor 
applications, the areal density is preferably equal to or less than about 
12 kg/m.sup.2. In the more preferred embodiments of the invention, the 
areal density is equal to or less than about 7 kg/m.sup.2, and in the most 
preferred embodiments of the invention, the areal density is equal to or 
less than about 6.5 kg/m.sup.2. 
Substrate layer 14 may vary widely, the only requirement is that it be 
flexible as defined above. For example, substrate layer 14 may be a 
flexible polymer or elastomeric film formed from a thermoplastic or 
elastomeric resin. Such thermoplastic and elastomeric resins for use in 
the practice of this invention may vary widely. Illustrative of useful 
thermoplastic resins are polylactones such as poly(pivalolactone), 
poly(e-caprolactone) and the like; polyurethanes derived from reaction of 
diisocyanates such as 1,5-naphthalene diisocyanate, p-phenylene 
diisocyanate, m-phenylene diisocyanate, 2,4-toluene diisocyanate, 
4,4'-diphenylmethane diisocyanate, 
3,3'-dimethyl-4,4'-diphenylisopropylidiene diisocyanate, 
3,3'-dimethyl-4,4'-diphenyl diisocyanate, 
3,3'-dimethyl-4,4'-dephenylmethane diisocyanate, 
3,3'-dimethyoxy-4,4'-biphenyl diisocyanate, dianisidine diisocyanate, 
tolidine diisocyanate, hexamethylene diisocyanate, 
4,4'-diisocyananodiphenylemthane and the like and linear long-chain diols 
such as poly(tetramethylene adipate), poly(ethylene adipate), 
poly(1,4-butylene adipate), poly(ethylene adipate), polyether diols and 
the like; polycarbonates such as poly[1,1-ether bis(4-phenyl carbonate], 
poly[1,1-ether bis(4-phenyl) carbonate], poly[diphenylmethane 
bis-(4-phenyl) carbonate], poly[1,1-cyclohexane bis-(4-phenyl) carbonate], 
poly[1,1-cyclohexane bis(4-phenyl carbonate] and the like; poly sulfones; 
polyether ether ketones; polymides such as poly(4-amino butyric acid), 
poly(hexamethylene adipamide), poly(6-aminohexanoic aicd), poly(m-xylylene 
adipamide), poly(p-xylylene sebacamide), poly 2,2,2-trimethyl 
hexamethylene terephthalamide), poly(metaphenyleneisophthalamide) 
(Nomex.RTM.), poly(p-phenylene terephthalamide) (Kevlar.RTM.), and the 
like; polyesters such as poly(ethylene azelate), 
poly(ethylene-1,5-naphthalate), poly(ethylene oxybenzoate) (A-Tell), 
poly(ethylene oxybienzoate) (A-Tell), poly(para-hydroxy benzoate) 
(Ekonol), poly(1,4-cyclohexylidene dimethylene terephthalate) (Kodel)(as), 
poly(1,4-cyclohexylidene dimethylene terephthalate) (Kodel)(trans), 
polyethylene terephthalate terephthalate and the like; poly(arylene 
oxides) such as poly(2,6-diphenyl-1,4-phenylene oxide), 
poly(2,6-diphenyl-1,4-phenylene oxide) and the like; poly(arylene 
sulfides) such as poly(phenylene sulfide) and the like; polyetherimides; 
thermoplastic elastomers such as polyurethane elastomers, 
fluoroelastomers, butadiene/acrylonitrule elastomers, block copolymers, 
made up of segments of glassy or crystalline blocks such as polystyrene, 
poly(vinyltoluene), poly(t-butyl styrene), polyester and the like and the 
elastomeric blocks such as polybutadiene, polyisoprene, ethylene/propylene 
copolymers, ethylene/butylene copolymers, polyether ester and the like as 
for example the copolymers in polystyrene/polybutadiene/polystrene block 
copolymer manufactured by Shell Chemical Company under the trade name of 
Kraton.RTM.; vinyl polymer and their copolymers such as polyvinyl acetate, 
polyvinyl alcohol, polyvinyl chloride, polyvinyl butyral, polyvinylidene 
chloride, ethylene/vinyl acetate copolymers, and the like; polyacrylics, 
polyacrylate and their copolymers such as polyethyl acrylate, poly(n-butyl 
acrylate), polymethyl methacrylate, polyethyl methacrylate, poly(n-butyl 
methacrylate), polyacrylamide, polyacrylonitrile, polyacrylic acid, 
ethylene/acrylic acid copolymers, methyl methacrylate/styrene copolymers, 
ethylene/ethyl acrylate copolymers, methacrylated butadiene/styrene 
copolymers and the like; polyolefins such as low density polyethylene, 
polyolefins such as low density polyethylene, polypropylene, chlorinated 
low density polyethlene, poly(4-methyl-1-pentene) and the like; ionomers; 
and polyepichlorohydrins; polycarbonates and the like. 
Substrate layer 14 may also comprise a network of fibers either alone or 
dispersed in a matrix. For purposes of the present invention, fiber is 
defined as an elongated body, the length dimension of which is much 
greater than the dimensions of width and thickness. Accordingly, the term 
fiber as used herein includes a monofilament elongated body, a 
multifilament elongated body, ribbon, strip, and the like having regular 
or irregular cross sections. The term fibers includes a plurality of any 
one or combination of the above. 
The cross-section of fibers for use in this invention may vary widely. 
Useful fibers may have a circular cross-section, oblong cross-section or 
irregular or regular multi-lobal cross-section having one or more regular 
or irregular lobes projecting from the linear or longitudinal axis of the 
fibers. In the particularly preferred embodiments of the invention, the 
fibers are of substantially circular or oblong cross-section and in the 
most preferred embodiments are of circular or substantially circular 
cross-section. 
Layer 14 may be formed from fibers alone, or from fibers coated with a 
suitable polymer, as for example, a polyolefin, polyamide, polyester, 
polydiene such as a polybutadiene, urethanes, diene/olefin copolymers, 
poly(styrene/butadiene/styrene) block copolymers, and a wide variety of 
elastomers. Substrate layer 14 may also comprise a network of a fibers 
dispersed in a polymeric matrix as for example a matrix of one or more of 
the above referenced polymers to form a flexible composite as described in 
more detail in U.S. Pat. Nos.4,623,574; 4,748,064; 4,916,000; 4,403,012; 
4,457,985; 4,650,710; 4,681,792; 4,737,401; 4,543,286; 4,563,392; and 
4,501,856. Regardless of the construction, substrate layer 14 is such that 
article 10 has the required degree of flexibility. 
The fibers in substrate layer 14 may be arranged in networks having various 
configurations. For example, a plurality of fibers can be grouped together 
to form twisted or untwisted yarn bundles in various alignments. The 
filaments or yarn may be formed as a felt, knitted or woven (plain, 
basket, satin and crow feet weaves, etc.) into a network, fabricated into 
non-woven fabric, arranged in parallel array, layered, or formed into a 
woven fabric by any of a variety of conventional techniques. Among these 
techniques, for ballistic resistance applications we prefer to use those 
variations commonly employed in the preparation of aramid fabrics for 
ballistic-resistant articles. For example, the techniques described in 
U.S. Pat. No. 4,181,768 and in M. R. Silyquist et al., J. Macromol Sci. 
Chem., A7(1), pp. 203 et. seq. (1973) are particularly suitable. 
The type of fibers used in the fabrication of substrate layer 14 may vary 
widely depending on the application. Useful fibers may be inorganic or 
organic fibers having varying elasticity, tenacity and modulus. For 
example, in those instances where layers 14 will not provide penetration 
resistance and are merely to support planar bodies 16, fibers having 
relatively low tenacities (ie less than about 5 grams/denier and low 
tensile modulus (ie less than about 25 grams/denier) may be used. On the 
other hand, in those applications where layers 14 will provide some 
penetration resistance fibers having relative high tenacity (ie greater 
than or equal to about 5 grams/denier) and high tensile modulus (ie 
greater than or equal to about 25 grams/denier.) In the preferred 
embodiments of the invention layers 14 will contribute to the penetration 
resistance. Preferred fibers for use in the practice of this invention are 
those having a tenacity equal to or greater than about 10 grams/denier 
(g/d) (as measured by an Instron Tensile Testing machine), a tensile 
modulus equal to or greater than about 25 g/d (as measured by an Instron 
Tensile Testing machine) and an energy-to-break equal to or greater than 
about 8 joules/gram. Particularly preferred fibers are those having a 
tenacity equal to or greater than about 15 g/d, a tensile modulus equal to 
or greater than about 150 g/d and energy-to-break equal to or greater than 
about 30 joules/grams. Amongst these particularly preferred embodiments, 
most preferred are those embodiments in which the tenacity of the fibers 
is equal to or greater than about 20 g/d, the tensile modulus is equal to 
or greater than about 1000 g/d, and the energy-to-break is equal to or 
greater than about 35 joules/gram. In the practice of this invention, 
filaments of choice have a tenacity equal to or greater than about 30 g/d, 
the tensile modulus is equal to or greater than about 1300 g/d and the 
energy-to-break is equal to or greater than about 40 joules/gram. 
The denier of the fiber may vary widely. In general, fiber denier is equal 
to or less than about 4000. In the preferred embodiments of the invention, 
fiber denier is from about 10 to about 4000, the more preferred 
embodiments of the invention fiber denier is from about 10 to about 1000 
and in the most preferred embodiments of the invention, fiber denier is 
from about 10 to about 400. Useful inorganic fibers include S-glass 
fibers, E-glass fibers, carbon fibers, boron fibers, alumina fibers, 
zirconia-silica fibers, alumina-silica fibers and the like. 
Illustrative of useful organic fibers are those composed of polyesters, 
polyolefins, polyetheramides, fluoropolymers, polyethers, celluloses, 
phenolics, polyesteramides, polyurethanes, epoxies, aminoplastics, 
polysulfones, polyetherketones, polyetheretherketones, polyesterimides, 
polyphenylene sulfides, polyether acryl ketones, poly(amideimides), and 
polyimides. Illustrative of other useful organic filaments are those 
composed of aramids (aromatic polyamides), such as poly(m-xylylene 
adipamide), poly(p-xylylene sebacamide), poly 2,2,2-trimethylhexamethylene 
terephthalamide), poly (piperazine sebacamide), poly (metaphenylene 
isophthalamide) and poly (p-phenylene terephthalamide); aliphatic and 
cycloaliphatic polyamides, such as the copolyamide of 30% hexamethylene 
diammonium isophthalate and 70% hexamethylene diammonium adipate, the 
copolyamide of up to 30% bis-(-amidocyclohexyl)methylene, terephthalic 
acid and caprolactam, polyhexamethylene adipamide (nylon 66), 
poly(butyrolactam) (nylon 4), poly (9-aminonoanoic acid) (nylon 9), 
poly(enantholactam) (nylon 7), poly(capryllactam) (nylon 8), 
polycaprolactam (nylon 6), poly (p-phenylene terephthalamide), 
polyhexamethylene sebacamide (nylon 6,10), polyaminoundecanamide (nylon 
11), polydodeconolactam (nylon 12), polyhexamethylene isophthalamide, 
polyhexamethylene terephthalamide, polycaproamide, poly(nonamethylene 
azelamide) (nylon 9,9), poly(decamethylene azelamide) (nylon 10,9), 
poly(decamethylene sebacamide) (nylon 10,10), 
poly[bis-(4-aminocyclothexyl) methane 1,10decanedicarboxamide] (Qiana) 
(trans), or combination thereof; and aliphatic, cycloaliphatic and 
aromatic polyesters such as poly(1,4-cyclohexlidene dimethyl 
eneterephathalate) cis and trans, poly(ethylene-1,5-naphthalate), 
poly(ethylene-2,6-naphthalate), poly(1,4-cyclohexane dimethylene 
terephthalate) (trans), poly(decamethylene terephthalate), poly(ethylene 
terephthalate), poly(ethylene isophthalate), poly(ethylene oxybenozoate), 
poly(para-hydroxy benzoate), poly(dimethylpropiolactone), 
poly(decamethylene adipate), poly(ethylene succinate), poly(ethylene 
azelate), poly(decamethylene sebacate), poly(-dimethyl-propiolactone), and 
the like. Also illustrative of useful organic fibers are those of liquid 
crystalline polymers such as lyotropic liquid crystalline polymers which 
include polypeptides such as poly-.alpha.-benzyl L-glutamate and the like; 
aromatic polyamides such as poly(1,4-benzamide), poly(chloro-1,4-phenylene 
terephthalamide), poly(1,4-phenylene fumaramide), 
poly(chloro-1,4-phenylene fumaramide), poly(4,4'-benzanilide trans, 
trans-muconamide), poly(1,4-phenylene mesaconamide), poly(1,4-phenylene) 
(trans-1,4-cyclohexylene amide), poly(chloro-1,4-phenylene) 
(trans-1,4-cyclohexylene amide), poly(1,4-phenylene 
1,4-dimethyl-trans-1,4-cyclohexylene amide), poly(1,4-phenylene 
2,5-pyridine amide), poly(chloro-1,4-phenylene 2,5-pyridine amide), 
poly(3,3'-dimethyl-4,4'-biphenylene 2,5-pyridine amide), 
poly(1,4-phenylene 4,4'-stilbene amide), poly(chloro-1,4-phenylene 4,4 
'-stilbene amide), poly(1,4-phenylene 4,4'-azobenzene amide), 
poly(4,4'-azobenzene 4,4'-azobenzene amide), poly(1,4-phenylene 
4,4'-azoxybenzene amide), poly(4,4'-azobenzene 4,4'-azoxybenzene amide), 
poly(1,4-cyclohexylene 4,4'-azobenzene amide), poly(4,4'-azobenzene 
terephthal amide), poly(3,8-phenanthridinone terephthal amide), 
poly(4,4'-biphenylene terephthal amide), poly(4,4'-biphenylene 
4,4'-bibenzo amide), poly(1,4-phenylene 4,4'-bibenzo amide), 
poly(1,4-phenylene 4,4'-terephenylene amide), poly(1,4-phenylene 
2,6-naphthal amide), poly(1,5-naphthylene terephthal amide), 
poly(3,3'-dimethyl-4,4-biphenylene terephthal amide), 
poly(3,3'-dimethoxy-4,4'-biphenylene terephthal amide), 
poly(3,3'-dimethoxy-4,4-biphenylene 4,4'-bibenzo amide) and the like; 
polyoxamides such as those derived from 2,2-dimethyl-4,4'diamino biphenyl 
and chloro-1,4-phenylene diamine; polyhydrazides such as poly 
chloroterephthalic hydrazide, 2,5-pyridine dicarboxylic acid hydrazide) 
poly(terephthalic hydrazide), poly(terephthalicchloroterephthalic 
hydrazide) and the like; poly(amide-hydrazides) such as poly(terephthaloyl 
1,4 amino-benzhydrazide) and those prepared from 4-amino-benzhydrazide, 
oxalic dihydrazide, terephthalic dihydrazide and para-aromatic diacid 
chlorides; polyesters such as those of the compositions include 
poly(oxy-trans-1,4-cyclohexyleneoxycarbonyl-trans-1,4 -cyclohexylenecarb 
onyl-.beta.-oxy-1,4-phenyl-eneoxyterephthaloyl) and 
poly(oxy-cis-1,4-cyclohexyleneoxycarbonyl-trans-1,4-cy 
clohexylenecarbonyl-.beta.-oxy-1,4-phenyleneoxyterephthal oyl) in 
methylene chloride-o-cresol 
poly[(oxy-trans-1,4-cyclohexylene-oxycarbonyl-trans-1,4 
-cyclohexylenecarbonyl-b-oxy-(2-methyl-1,4-phenylene) oxy-terephthaloyl)] 
in 1,1,2,2-tetrachloro-ethane-o-chlorophenol-phenol (60:25:15 
vol/vol/vol), poly[oxy-trans-1,4-cyclohexyleneoxycarbonyl-trans-1,4-cycloh 
exylenecarbonyl-b-oxy(2-methyl-1,3-phenylene)oxy -terephthaloyl] in 
o-chlorophenol and the like; polyazomethines such as those prepared from 
4,4'-diaminobenzanilide and terephthaldehyde, methyl-1,4-phenylenediamine 
and terephthalaldelyde and the like; polyisocyanides such as poly(-phenyl 
ethyl isocyanide), poly(n-octyl isocyanide) and the like; polyisocyanates 
such as poly(n-alkyl isocyanates) as for example poly(n-butyl isocyanate), 
poly(n-hexyl isocyanate) and the like; lyotropic crystalline polymers with 
heterocylic units such as poly(1,4-phenylene-2,6-benzobisthiazole)(PBT), 
poly(1,4- phenylene -2,6-benzobisoxazole) (PBO), 
poly(1,4-phenylene-1,3,4-oxadiazole), 
poly(1,4-phenylene-2,6-benzobisimidazole), poly[2,5(6)-benzimidazole] 
(AB-PBI), poly[2,6-(1,4-phneylene)-4-phenylquinoline], 
poly[1,1'-(4,4'-biphenylene)-6,6'-bis(4-phenylquinolin e)] and the like; 
polyorganophosphazines such as polyphosphazine, polybisphenoxyphosphazine, 
poly[bis(2,2,2-trifluoroethyelene) phosphazine] and the like; metal 
polymers such as those derived by condensation of 
trans-bis(tri-n-butylphosphine) platinum dichloride with a bisacetylene or 
trans-bis(tri-n-butylphosphine)bis(1,4-butadienyl)platinum and similar 
combinations in the presence of cuprous iodine and an amide; cellulose and 
cellulose derivatives such as esters of cellulose as for example 
triacetate cellulose, acetate cellulose, acetate-butyrate cellulose, 
nitrate cellulose, and sulfate cellulose, ethers of cellulose as for 
example, ethyl ether cellulose, hydroxymethyl ether cellulose, 
hydroxypropyl ether cellulose, carboxymethyl ether cellulose, ethyl 
hydroxyethyl ether cellulose, cyanoethylethyl ether cellulose, 
ether-esters of cellulose as for example acetoxyethyl ether cellulose and 
benzoyloxypropyl ether cellulose, and urethane cellulose as for example 
phenyl urethane cellulose; thermotropic liquid crystalline polymers such 
as celluloses and their derivatives as for example hydroxypropyl 
cellulose, ethyl cellulose propionoxypropyl cellulose, thermotropic liquid 
crystalline polymers such as celluloses and their derivatives as for 
example hydroxypropyl cellulose, ethyl cellulose propionoxypropyl 
cellulose; thermotropic copolyesters as for example copolymers of 
6-hydroxy-2- naphthoic acid and p-hydroxy benzoic acid, copolymers of 
6-hydroxy-2-naphthoic acid, terephthalic acid and p-amino phenol, 
copolymers of 6-hydroxy-2-naphthoic acid, terephthalic acid and 
hydroquinone, copolymers of 6-hydroxy-2-naphthoic acid, p-hydroxy benzoic 
acid, hydroquinone and terephthalic acid, copolymers of 2,6-naphthalene 
dicarboxylic acid, terephthalic acid, isophthalic acid and hydroquinone, 
copolymers of 2,6-naphthalene dicarboxylic acid and terephthalic acid, 
copolymers of p-hydroxybenzoic acid, terephthalic acid and 
4,4'-dihydoxydiphenyl, copolymers of p-hydroxybenzoic acid, terephthalic 
acid, isophthalic acid and 4,4'-dihydroxydiphenyl, p-hydroxybenzoic acid, 
isophthalic acid, hydroquinone and 4,4'-dihydroxybenzophenone, copolymers 
of phenylterephthalic acid and hydroquinone, copolymers of 
chlorohydroquinone, terephthalic acid and p-acetoxy cinnamic acid, 
copolymers of chlorohydroquinone, terephthalic acid and ethylene 
dioxy-4,4'-dibenzoic acid, copolymers of hydroquinone, methylhydroquinone, 
p-hydroxybenzoic acid and isophthalic acid, copolymers of 
(1-phenylethyl)hydroquinone, terephthalic acid and hydroquinone, and 
copolymers of poly(ethylene terephthalate) and p-hydroxybenzoic acid; and 
thermotropic polyamides and thermotropic copoly(amide-esters). 
Also illustrative of useful organic filaments for use in the fabrication of 
substrate layer 14 are those composed of extended chain polymers formed by 
polymerization of .alpha., .beta.-unsaturated monomers of the formula: 
EQU R.sub.1 R.sub.2 --C=CH.sub.2 
wherein: 
R.sub.1 and R.sub.2 are the same or different and are hydrogen, hydroxy, 
halogen, alkylcarbonyl, carboxy, alkoxycarbonyl, heterocycle or alkyl or 
aryl either unsubstituted or substituted with one or more substituents 
selected from the group consisting of alkoxy, cyano, hydroxy, alkyl and 
aryl. Illustrative of such polymers of .alpha., .beta.-unsaturated 
monomers are polymers including polystyrene, polyethylene, polypropylene, 
poly(1-octadecene), polyisobutylene, poly(1-pentene), 
poly(2-methylstyrene), poly(4-methylstyrene), poly(1-hexene), 
poly(1-pentene), poly(4-methoxystrene), poly(5-methyl-1-hexene), 
poly(4-methylpentene), poly (1-butene), polyvinyl chloride, polybutylene, 
polyacrylonitrile, poly(methyl pentene-1), poly(vinyl alcohol), 
poly(vinyl-acetate), poly(vinyl butyral), poly(vinyl chloride), 
poly(vinylidene chloride), vinyl chloride-vinyl acetate chloride 
copolymer, poly(vinylidene fluoride), poly(methyl acrylate, poly(methyl 
methacrylate), poly(methacrylo-nitrile), poly(acrylamide), poly(vinyl 
fluoride), poly(vinyl formal), poly(3-methyl-1-butene), poly(1-pentene), 
poly(4-methyl-1-butene), poly(1-pentene), poly(4-methyl-1-pentene, 
poly(1-hexane), poly(5-methyl-1-hexene), poly(vinyl-cyclopentane), 
poly(vinylcyclothexane), poly(a-vinyl-naphthalene), poly(vinyl methyl 
ether), poly(vinyl-ethylether), poly(vinyl propylether), poly(vinyl 
carbazole), poly(vinyl pyrolidone), poly(2-chlorostyrene), 
poly(4-chlorostyrene), poly(vinyl formate), poly(vinyl butyl ether), 
poly(vinyl octyl ether), poly(vinyl methyl ketone), 
poly(methyl-isopropenyl ketone), poly(4-phenylstyrene) and the like. 
In the most preferred embodiments of the invention, article 10 includes a 
fibrous substrate layer 14, which may include high molecular weight 
polyethylene fibers, high molecular weight polypropylene fibers, nylon 
fibers (such as nylon, nylon 66, etc), polyester fibers such as 
poly(ethylene terephthalate) fibers, aramid fibers, high molecular weight 
polyvinyl alcohol fibers, high molecular weight polyacrylonitrile fibers 
or mixtures thereof. U.S. Pat. No. 4,457,985 generally discusses such high 
molecular weight polyethylene and polypropylene fibers, and the disclosure 
of this patent is hereby incorporated by reference to the extent that it 
is not inconsistent herewith. In the case of polyethylene, suitable fibers 
are those of molecular weight of at least 150,000, preferably at least one 
million and more preferably between two million and five million. Such 
extended chain polyethylene (ECPE) fibers may be grown in solution as 
described in U.S. Pat. No. 4,137,394, U.S. Pat. No. 4,356,138, issued Oct. 
26, 1982, or fibers spun from a solution to form a gel structure, as 
described in German Off. 3,004,699 and GB 2051667, and especially 
described in U.S. Pat. No. 4,551,296 (see EPA 64,167, published Nov. 10, 
1982). As used herein, the term polyethylene shall mean a predominantly 
linear polyethylene material that may contain minor amounts of chain 
branching or comonomers not exceeding 5 modifying units per 100 main chain 
carbon atoms, and that may also contain admixed therewith not more than 
about 50 wt % of one or more polymeric additives such as 
alkene-1-polymers, in particular low density polyethylene, polypropylene 
or polybutylene, copolymers containing mono-olefins as primary monomers, 
oxidized polyolefins, graft polyolefin copolymers and polyoxymethylenes, 
or low molecular weight additives such as anti-oxidants, lubricants, 
ultra-violet screening agents, colorants and the like which are commonly 
incorporated by reference. Depending upon the formation technique, the 
draw ratio and temperatures, and other conditions, a variety of properties 
can be imparted to these fibers. The tenacity of the fibers should be at 
least 15 grams/denier (as measured by an Instron Testing Machine), 
preferably at least 20 grams/denier, more preferably at least 25 
grams/denier and most preferably at least 30 grams/denier. Similarly, the 
tensile modulus of the fibers, as measured by an Instron Tensile Testing 
Machine, is at least 300 grams/denier, preferably at least 500 
grams/denier and more preferably at least 1,000 grams/denier and most 
preferably at least 1,200 grams/denier. These highest values for tensile 
modulus and tenacity are generally obtainable only by employing solution 
grown or gel fibers processes. 
Similarly, highly oriented polypropylene fibers of molecular weight at 
least 200,000, preferably at least one million and more preferably at 
least two million may be used. Such high molecular weight polypropylene 
may be formed into reasonably well oriented fibers by the techniques 
prescribed in the various references referred to above, and especially by 
the technique of U.S. Pat. No. 4,551,296. Since polypropylene is a much 
less crystalline material than polyethylene and contains pendant methyl 
groups, tenacity values achievable with polypropylene are generally 
substantially lower than the corresponding values for polyethylene. 
Accordingly, a suitable tenacity is at least 8 grams/denier (as measured 
by an Instron Tensile Testing Machine), with a preferred tenacity being at 
least 11 grams/denier. The tensile modulus for polypropylene is at least 
160 grams/denier, preferably at least 200 grams/denier. The particularly 
preferred ranges for the above-described parameters can advantageously 
provide improved performance in the final article. 
High molecular weight polyvinyl alcohol fibers having high tensile modulus 
are described in U.S. Pat. No. 4,440,711, which is hereby incorporated by 
reference to the extent it is not inconsistent herewith. In the case of 
polyvinyl alcohol (PV-OH), PV-OH fiber of molecular weight of at least 
about 200,000. Particularly useful PV-OH fiber should have a tensile 
modulus of at least about 300 g/d (as measured by an Instron Tensile 
Testing Machine), a tenacity of at least 7 g/d (preferably at least about 
10 g/d, more preferably at about 14 g/d, and most preferably at least 
about 17 g/d), and an energy-to-break of at least about 8 joules/gram. 
PV-OH fibers having a weight average molecular weight of at least about 
200,000, a tenacity of at least about 10 g/d, a tensile modulus of at 
least about 300 g/d, and an energy-to-break of about 8 joules/gram are 
more useful in producing a ballistic resistant article. PV-OH fiber having 
such properties can be produced, for example, by the process disclosed in 
U.S. Patent No. 4,599,267. 
In the case of polyacrylonitrile (PAN), PAN fibers of molecular weight of 
at least about 400,000. Particularly useful PAN fibers should have a 
tenacity of at least about 10 g/d and an energy-to-break of at least about 
8 joules/gram. PAN fibers having a molecular weight of at least about 
400,000, a tenacity of at least about 15 to about 20 g/d and an 
energy-to-break of at least 8 joules/gram is most useful in producing 
ballistic resistant articles; and such fibers are disclosed, for example, 
in U.S. Pat. No. 4,535,027. 
In the case of aramid fibers, suitable aramid fibers formed principally 
from aromatic polyamide are described in U.S. Pat. No. 3,671,542, which is 
hereby incorporated by reference. Preferred aramid fiber will have a 
tenacity of at least about 20 g/d (as measured by an Instron Tensile 
Testing Machine), a tensile modulus of at least about 400 g/d (as measured 
by an Instron Tensile Testing Machine) and an energy-to-break at least 
about 8 joules/gram, and particularly preferred aramid fiber will have a 
tenacity of at least about 20 g/d, a modulus of at least about 480 g/d and 
an energy-to-break of at least about 20 joules/gram. Most preferred aramid 
fibers will have a tenacity of at least about 20 g/denier, a modulus of at 
least about 900 g/denier and an energy-to-break of at least about 30 
joules/gram. For example, poly(phenyleneterephthalamide) fibers produced 
commercially by Dupont Corporation under the trade name of Kevlar.RTM. 29, 
49, 129 and 149 having moderately high moduli and tenacity values are 
particularly useful in forming ballistic resistant composites. Also useful 
in the practice of this invention is poly(metaphenylene isophthalamide) 
fibers produced commercially by Dupont under the tradename Nomex.RTM.. 
In the case of liquid crystal copolyesters, suitable fibers are disclosed, 
for example, in U.S. Pat. Nos. 3,975,487; 4,118,372; and 4,161,470, hereby 
incorporated by reference. Tenacities of about 15 to about 30 g/d (as 
measured by an Instron Tensile Testing Machine) and preferably about 20 to 
about 25 g/d, and tensile modulus of about 500 to 1500 g/d (as measured by 
an Instron Tensile Testing Machine) and preferably about 1000 to about 
1200 g/d are particularly desirable. 
As depicted in FIGS. 5 to 23, planar bodies 16 contain one or more flexing 
seams 32 to allow flexing of one or more portions of planar bodies 16 
about seams 32. In general, the greater the number of flexing seams 32, 
the greater the flexibility of article 10, and conversely, the fewer the 
number of flexing seams 32, the less the flexibility. Thus, the number of 
flexing seams 32 will be varied to provide the desired degree of 
flexibility to the appropriate portion of article 10. For example, for 
frontal portions of article 10 where relatively less flexibility is 
required planar bodies 16 will include fewer seams 32. On the other hand, 
side portions of article 10 where more flexibility is required planar 
bodies 16 having a relatively larger number seams 32 are employed. In the 
preferred embodiments of the invention, where more flexibility is 
required, planar bodies 16 will include two or more flexing seams 32 as 
described in FIGS. 9 and 11 to 23. In the more preferred embodiments of 
this invention where more flexibility is required planar bodies 16 will 
include three or more flexing seams 32 as described in FIGS. 9, 14, 15, 22 
and 23. In those embodiments of the invention where planar bodies 16 
include two or more seams, the seams may be parallel or at an angle with 
respect to each other. In the preferred embodiments, the seams are at an 
angle in order to allow flexing in multiple directions. Such constructions 
regardless of the thickness and rigidity of planar body 16 can drape 
around doubly curved surfaces and thus exhibit the desired flexibility. In 
the more preferred embodiments of the invention, the seams are at an angle 
of from about 30.degree. to about 150.degree., preferably at an angle of 
from about 60.degree. C. to about 120.degree. C. As depicted in FIGS. 9, 
12, 14, 15, 19, 20, 22 and 23 in the most preferred embodiments of the 
invention, the seams are such that the planar body 16 is divided into 
triangular shaped portions, preferably right angle triangles, equilateral 
triangles or a combination thereof and more preferably equilateral 
triangles). Seams 32 may also sub divide planar body 16 into shapes 
obtainable by fusion of two or more triangles at appropriate edges, such 
as hexagons, parallelograms, trapezoids and the like or a combination of 
such shapes and triangular shaped bodies, especially equilateral 
triangular shaped bodies see for example FIGS. 11, 12, 16, 17 and 21. 
Bodies 16 are preferably positioned such that at least one seam of one 
planar body 16 is in substantial alignment with at least one seam of an 
adjacent planar body 16, preferably such that the combination of planar 
bodies 16 provide at least one, preferably at least two and more 
preferably three or more seams of the same or different seam directions 
along which article 10 may flex. 
Flexing seams 32 can be formed by any conventional means which will allow a 
flexing portion of planar body 16 to flex away from the plane of a 
non-flexing portion of body 16. For example, one method which can be 
employed is spirally wound metallic or polymeric thread. In these 
embodiments, the thread is preferably formed from an elastomeric material 
because while it holds the sides of the flexing and non flexing portions 
of planar body 16 together, it easily allows significant flexing. Although 
such elastomeric material may allow momentary openings between non flexing 
portions of planar bodies 16 and flexing portions under severe flexing, 
the structure should close immediately when such flexing ceases. Still 
other suitable hinging means include flexible tape, taping adjacent sides 
together; conventional hinges; rings; pins and the like. Various means 
used to form the flexible seams are not critical provided that they allow 
some degree of flexing along the seam. 
The nature of the flexing seam 32 may vary widely. As depicted in FIGS. 9 
to 21, straight flexing seams 32 are employed. Straight flexing seams 32 
may have perpendicular side walls or the side walls may be at an angle or 
bevelled or a combination. The mating sides of flexing seams 32 may be 
other than straight. For example, as depicted in FIG. 22 the mating 
surfaces may be curved or as depicted in FIG. 23, the mating surfaces may 
be saw toothed. In these designs, depending on the length of any straight 
portion of the mated sides, penetration of seams by objects such as knives 
and the like is more difficult. 
As depicted in FIGS. 2 to 18, article 10 of this invention includes a 
plurality of planar bodies 16 affixed to one or more surfaces of one or 
more of substrate layers 14. As a ballistic missile impacts a planar body 
16, the missile can be broken and/or enlarged and flattened to increase 
its impact area and decrease the velocity of the missile. Means for 
attaching planar bodies 16 to substrate layer 14 may vary widely and may 
include any means normally used in the art to provide this function. 
Illustrative of useful attaching means are adhesives such as those 
discussed in R. C. Liable, Ballistic Materials and Penetration Mechanics, 
Elsevier Scientific Publishing Co. (1980). Illustrative of other useful 
attaching means are bolts, screws, staples mechanical interlocks, 
stitching, or a combination of any of these conventional methods. As 
depicted in FIGS. 2, 5, 6 and 13 in the preferred embodiments of the 
invention planar bodies 16 are stitched to the surface of layer 14. 
Optionally, the stitching may be supplemented by and/or replaced by other 
types of securing means such as adhesive. 
As depicted in the FIGS. 2, 5 to 23 and 27 to 29 flexing and non flexing 
portions of planar bodies 16 may be affixed to a surface of layer 14 by 
stitches 22 which extend through one or more of substrate layers 14. For 
example, in the embodiment of FIG. 4, one portion of planar 16 may be 
affixed to the surface of layer 14 by stitches 22 which extend through 
layers 14a', 14b', 14c', 14d', 14e', 14f', 14g', 14h', 14i', while other 
portions are connected by stitches 22 which extend only through substrate 
layer 14a', 14b', and 14c', or through layers 14a' and 14b or even through 
layers 14a'. In general, the greater the number of layers 14 through which 
stitches 22 extend, the less the extent to which the portion of planar 
body 16 affixed by such stitches can flex along a flexing seam 32; and 
conversely, the fewer the layers through which stitches 22 extend, the 
greater the extent to which the portion of planar body 16 affixed by such 
stitches may flex along a flexing seam 32. Thus, where greater flexibility 
is desired, stitches 22 extend through fewer substrate layer 14 and were 
less flexibility is desired, stitches 22 extend through more layers 14. 
For example, in the case of the preferred triangular planar bodies of 
FIGS. 14, 22 and 23, the central triangular portion 34 is affixed to a 
surface substrate layer 14 by stitches 22 (not depicted) which extend 
through more substrate layers than the stitches 22 which affix portions 
36, 38 and 40. A result is that portions 36, 28 and 40 are able to flex 
more than portion 34. Similarily, in the case of the preferred embodiments 
of FIGS. 19, 20 and 21 in which planar body 16 are of shape which can be 
sub-divided into triangular shaped portions such as parallogram and 
trapzoidal shapes, one or more portions of the body can be affixed to a 
surface by stitches 22 extending through a relatively large number of 
layers 14 and one or more portions can be affixed by stitches 22 extending 
through a relatively few number of layers 14. For example, in FIGS. 19, 20 
and 21 portion 42 and 44 of FIG. 19, portion 50 of FIG. 20 and portion 56 
of FIG. 21 can be affixed by stitches 22 extending through a larger number 
of layers 14 than the number of layers 14 through which stitches 22 affix 
portions 46 and 48 of FIG. 19, portions 52 and 54 of FIG. 20 and portions 
58 and 60 of FIG. 21. 
As depicted in FIG. 3, 4, 5, and 6 in cross-section, article 10 comprises 
three distinct layers 12a, 12b and 12c, each consisting of a plurality of 
substrate layers 14, stitched together by horizontal stitches 18 and 
vertical stitches 20 (not depicted). Layer 12a is the outer layer which is 
exposed to the environment, and layer 12c is the inner layer closest to 
the body of the wearer. The two covering layers 12a and 12c sandwich a 
ballistic layer 12b, which, in the body armor of the figures comprises a 
plurality of stitched substrate layers 14a' to 14k' (FIG. 4) and 14a' to 
14i' (FIG. 3) having a plurality of planar bodies partially covering both 
outer surfaces of said plurality of layers 14 forming a pattern of covered 
areas 28 and uncovered areas 30 on the outer surfaces. As shown in FIG. 3, 
the plurality of planar bodies 26 are positioned on the two surfaces such 
that the covered areas 28 on one surface are aligned with the uncovered 
areas 30 on the other surface. In the preferred embodiments of the 
invention depicted in FIG. 3 and 4, each planar body 16 is uniformly 
larger than its corresponding uncovered area 30 such that planar bodies 16 
adjacent to an uncovered area 30 partially overlap with the corresponding 
planar body 16 (of the area 30) on the other outer surface of the 
plurality of layers 14 by some portion 32. The degree of overlap may vary 
widely, but in general is such that preferably more than about 90 area %, 
more preferably more than about 95 area % and most preferably more than 
about 99 area % of the uncovered areas 30 on an outer surface of the 
plurality of layers 14 are covered by its corresponding planar body 16 on 
the other outer surface of the plurality of layers 14. 
FIG. 4 depicts a variant of the embodiment of FIG. 3 which differs by 
placing planar bodies 16 on a surface of layer 12b and on a surface of 
layer 12(c). Corresponding parts are referred to by like numerals. 
As shown in the Figures, the position of planar bodies 16 can vary widely 
but is preferably chosen such that at least one seam 32 of adjacent planar 
bodies 16 are in substantial alignment. This results in seams in the 
composite as a whole which enhances flexibility. For example, planar 
bodies 16 may be on an outside surface of a fibrous layer 12 or may be 
encapsulated inside of the plurality of fibrous layers 14 on interior 
surfaces. As depicted in FIGS. 3 to 18, planar bodies 16 are preferably 
space filling and will provide more than one, preferably two or three and 
more preferably three semi-continuous or continuous seams in different 
directions which preferably intersect at an angle with each other 
(preferably at an angle of from about 30.degree. to about 150.degree., 
more preferably at an angle of from about 60.degree. to about 120.degree. 
and most preferably at an angle of about 60.degree.) in order to allow 
flexing in multiple directions. 
The number of planar bodies 16 may vary widely, the only requirement is 
that there is at least one planar body 16 bound to a surface of at least 
one layer 14. Planar bodies 16 can be affixed using any conventional means 
as for example bolts, screws, stitches, bolts and the like. In the 
preferred embodiments of the invention, planar bodies 16 are sewn to at 
least one surface of each layer 14, and the number and types of planar 
bodies 16 are such that article 10 has the required flexibility. 
The shape of planar bodies 16 and the area percent of layer 14 covered by 
planar bodies 16 may vary widely. For example, planar bodies 16 may be in 
the form of a sheet or sheet-like (e.g. contiguous or overlapping ribbons, 
steps, squares and the like preferably with rounded or truncated edges to 
minimize damage to substrate layer 14 which form a sheet-like layer) which 
is bonded to or in contact with 100 percent or substantially one hundred 
percent of a surface of layer 14. Alternatively, planar bodies 16 may be 
formed from a plurality of various geometrically shaped planar bodies 
(e.g. ribbons, hexagons, triangles, rectangles, squares, strips) which 
cover less than 100% of the surface of layer 14. In the preferred 
embodiments of this invention, planar bodies 16 affixed to a least about 5 
area percent of a major surface of substrate layer 14 based on the total 
area of said surface. In the more preferred embodiments of the invention, 
planar bodies 16 are affixed to at least about 20 area percent of a major 
surface of layer 14, and in the most preferred embodiments of the 
invention, planar bodies 16 are affixed to at least about 50 area percent 
of a major surface of a fibrous layer 14. 
Affixation of a planar bodies 16 to a substrate layer 14 as continuous 
sheet may cause stiffening of the structure. Although for certain 
applications this may be acceptable provided that article 10 has the 
required degree of flexibility, for many applications where relatively 
high penetration resistance and flexibility are desired, such as a 
ballistic resistant vest, it is desirable to affix planar bodies 16 to 
substrate layer 14 such that the desired flexibility is obtained. As shown 
in the Figures, this is preferably accomplished by affixing planar bodies 
16 as discontinuous geometric shapes. In these applications, it is 
preferred that the planar bodies 16 include highly penetration resistance 
structures formed from rigid ballistic resistant materials. Preferred 
geometric shapes of planar bodies 16 will be space filling and will be 
positioned to provide more than one (preferably at least two, more 
preferably three and most preferably three) different directions for 
continuous or semi continuous (preferably continuous) seams where seam 
directions are preferably at an angle to each other (more preferably at an 
angle of about 60.degree.) in order to allow flexing in multiple 
directions as depicted in FIGS. 5 to 8. Such constructions regardless of 
the thickness and rigidity of planar body 16 can drape around doubly 
curved surfaces and thus exhibit the desired flexibility. Primarily 
because of the improved flexibility a preferred construction consists of 
an arrangement of triangular shaped bodies (preferably right angle 
triangles, equilateral triangles or a combination thereof and more 
preferably equilateral triangles) which are arranged to be area filling as 
depicted in FIGS. 5 to 8 and 14 to 17. A desirable modification to this 
construction is the inclusion of compatible geometric shapes such as 
hexagons, parallelograms, trapezoids and the like, which correspond to 
shapes obtainable by fusion of two or more triangles at appropriate edges. 
As depicted in FIGS. 7, 8 and 9 to 12 the most compatible geometric shape 
is a hexagon. It should be noted that while in FIGS. 7 and 8 the hexagonal 
and triangular shaped bodies are positioned on the same surface of layer 
14, such positioning is not critical, and such bodies can be conveniently 
placed on more than one surface as for example in FIG. 3. Such space 
filling constructions allow a wide range of compromises between 
flexibility and minimization of seams and penetration resistance. One or 
more of the apexes of planar bodies 16 are preferably truncated or rounded 
which also enhances flexibility by allowing substrate layer 14 to flex 
away from body 16 between the attachment point and the perimeter. Planar 
bodies 16 preferably include eyes for stitching planar bodies 20 to a 
surface of layer 14 by way of stitches. Additional flexibility can be 
achieved by providing spacers between substrate layer 14 and planar bodies 
16. In these preferred embodiments, curvilinear planar bodies 18 such as a 
circular or oval shaped body 16 (not depicted) are positioned at the 
truncated or rounded apexes to provide for additional penetration 
resistance. Alternatively, a mixture of totally or partially truncated 
planar bodies 16 and partially truncated or untruncated planar bodies 16 
can be used in which the open areas at the truncated ends can be covered 
by the un-truncated ends of the adjacent partially truncated or 
untruncated planar body 16. Such space filling constructions allow a wide 
range of compromises between flexibility and minimization of seams, and 
maximization of penetration resistance. 
As shown in FIG. 3, 4 and 5 in the preferred embodiments of this invention, 
article 10 includes a plurality of layers 14 in which rigid substantially 
planar bodies 16 in adjacent layers 14 are offset to provide for 
continuous and overlapping rigid ballistic protection. 
In these embodiments, as shown in FIG. 4 article 10 preferably includes at 
least two layers 14 in which each layer 14 is partially covered with 
planar bodies 16 preferably forming an alternating pattern of covered 
areas 28 and uncovered areas 30. These layers are positioned in article 18 
such that uncovered areas 30 of one layer 14 are aligned with covered 
areas 28 of another layer 14 (preferably an adjacent layer) providing for 
partial or complete coverage of the uncovered areas of one layer 14 by the 
covered areas of an another layer 14. Alternatively, another preferred 
embodiment as depicted in FIG. 3 includes a layer 14 in which each side of 
the layer is partially covered with bodies 16 and where the bodies are 
positioned such that the covered areas 28 on one side of the layer are 
aligned with the uncovered areas 30 on the other side of the layer. In the 
preferred embodiments of the invention, the surface of layer 14 s covered 
with planar bodies 16 such that the bodies are uniformly larger than the 
uncovered mated surface of the other layers 12 or the other surface of the 
same layer providing for complete overlap. This is preferably accomplished 
by truncation of the edges of the bodies 16 or otherwise modification of 
such edges to allow for closer placement of bodies 16 on the surface such 
that a covered area is larger than the complementary uncovered area 30. 
Extensive disalignment between the various fibrous layers 14, is prevented 
by the securing means 18 and 20. 
Planar bodies 16 are comprised of a "rigid" material which may vary widely 
depending on the uses of article 10. The term "rigid" as used in the 
present specification and claims is intended to include semi-flexible and 
semi-rigid structures that are not capable of being free standing, without 
collapsing which are not flexible when evaluated under Drape Test 1. In 
those embodiments of the invention where the planar bodies 16 are not 
intended to provide penetration resistance, as for example a floatation 
vest, vest for the control of transmission, absorption, reflection, and 
deflection of electromagnetic radiation, acoustical energy, flames, and 
fluids, transfer planar bodies 16 may be formed from a material which may 
be easily penetrated as for example a polymeric foam. On the other hand, 
if planar bodies 16 are to provide penetration resistance, then 
penetration resistant materials should be used for at least a part of 
their structure. In the preferred embodiments of the invention planar 
bodies 16 are formed from penetration resistant materials. The materials 
employed in the fabrication of penetration resistant planar bodies 16 may 
vary widely and may be any penetration resistant inorganic or organic 
materials. Illustrative of such materials are those described in G. S. 
Brady and H. R. Clauser, Materials Handbook, 12th Ed. (1986). Useful 
materials include high modulus polymeric materials such as polyamides as 
for example aramids, nylon-66, nylon-6 and the like; polyesters such as 
polyethylene terephthalate, polybutylene terephthalate, and the like; 
acetalo; polysulfones; polyethersulfones, polyacrylates; 
acrylonitrile/butadiene/styrene copolymers; polymer(amideimide); 
polycarbonates; polyphenylenesulfides; polyurethanes; polyphenyleneoxides; 
polyester carbonates polyesterimides; polymidies; polyetherimides; 
polymides; polyetheretherketone; epoxy resins; phenolic resins; 
polysulfides; silicones; polyacrylates; polyacrylics; polydienes, vinyl 
ester resins, modified phenolic resins; unsaturated polyester; allylic 
resins; alkyd resins, melamine and urea resins; polymer alloys and blends 
of thermoplastic resins one or more thermosetting resins and combinations 
one or more thereof; and interpenetrating polymer networks such as those 
of polycyanate ester of a polyol such as the dicyanoester of bisphenol-A 
and a thermoplastic such as a polysulfone. 
Planar bodies 16 may comprise a network of fibers as for example those 
described for use in the fabrication of fibrous substrate layer 14 
preferably aramid fibers, such as Kevlar.RTM. 29, 49, 129 and 149 aramid 
fibers, polyethylene fibers, polyethylene fibers such as Spectra.RTM. 900 
and Spectra.RTM. 1000 polyethylene fibers and combinations thereof 
dispersed in a matrix of one or more polymeric materials such as one or 
more thermoplastic resins one or more thermosetting resins or a 
combination thereof, such as polymers used to form the fibers of fibrous 
substrate layers 14. In these embodiments of the invention, the fibers are 
dispersed in a continuous phase of a matrix material which preferably 
substantially coats each filament contained in the fiber. The manner in 
which the filaments are dispersed may vary widely. The filaments may be 
aligned in a substantially parallel, unidirectional fashion, or filaments 
may by aligned in a multidirectional fashion with filaments at varying 
angles with each other. In the preferred embodiments of this invention, 
filaments in each layer are aligned in a substantially parallel, 
unidirectional fashion such as in a prepreg, pultruded sheet and the like. 
One such suitable arrangement is where the polymeric layer comprises a 
plurality of layers or laminates in which the coated filaments are 
arranged in a sheet-like array and aligned parallel to another along a 
common filament direction. Successive layers of such coated, 
uni-directional filaments can be rotated with respect to the previous 
layer to form a relatively flexible composite. An example of such laminate 
structures are composites with the second, third, fourth and fifth layers 
rotated +45.degree., -45.degree., 90.degree. and 0.degree., with respect 
to the first layer, but not necessarily in that order. Other examples 
include composites with 0.degree./90.degree. layout of yarn or filaments. 
Techniques for fabricating these laminated structures are described in 
greater detail in U.S. Pat. Nos. 4,916,000; 4,623,574; 4,748,064; 
4,457,985 and 4,403,012. 
Useful materials for the fabrication of planar bodies 16 also include 
multilayered fabric or fibrous composites in which the fabric or fibrous 
layers are secured by some securing means as for example stitching, 
adhesive, bolts, staples and the like. These fabrics can be woven or 
non-woven, and can be formed from the fibers described above for use in 
the fabrication of fibrous substrate layer 14 such as aramid fibers (such 
as Kevlar.RTM. 29, 49, 129 and 149 aramid fibers) polyethylene fibers 
(such as Spectra.RTM. 900 and Spectra.RTM. 1000 polyethylene fibers) and 
combinations thereof. 
Planar bodies 16 may also be formed from metal and non-metal ceramics. 
Illustrative of useful metal and non-metal ceramics are as those described 
in C. F. Liable, Ballistic Materials and Penetration Mechanics, Chapters 
5-7 (1980) and include single oxides such as aluminum oxide (Al.sub.2 
O.sub.3), barium oxide (BaO), beryllium oxide (BeO), calcium oxide (CaO), 
cerium oxide (Ce.sub.2 O.sub.3 and CeO.sub.2), chromium oxide (Cr.sub.2 
O.sub.3), dysprosium oxide (Dy.sub.2 O.sub.3), erbium oxide (Er.sub.2 
O.sub.3), europium oxide: (EuO, Eu.sub.2 O.sub.3, Eu.sub.2 O.sub.4 and 
(Eu.sub.16 O.sub.21), gadolinium oxide (Gd.sub.2 O.sub.3), hafnium oxide 
(HfO.sub.2), holmium oxide (Ho.sub.2 O.sub.3), lanthanum oxide (La.sub.2 
O.sub.3), luetetium oxide (Lu.sub.2 O.sub.3), magnesium oxide (MgO), 
neodymium oxide (Nd.sub.2 O.sub.3), niobium oxide: (NbO, Nb.sub.2 O.sub.3, 
and NbO.sub.2), Nb.sub.2 O.sub.5), plutonium oxide: (PuO, Pu.sub.2 
O.sub.3, and PuO.sub.2), praseodymium oxide: (PrO.sub.2, Pr.sub.6 
O.sub.11, and Pr.sub.2 O.sub.3), promethium oxide (Pm.sub.2 O.sub.3), 
samarium oxide (SmO and Sm.sub.2 O.sub.3), scandium oxide (Sc.sub.2 
O.sub.3), silicon dioxide (SiO.sub.2), strontium oxide (SrO), tantalum 
oxide (Ta.sub.2 O.sub.5), terbium oxide (Tb.sub.2 O.sub.5), terbium oxide 
(Tb.sub.2 O.sub.3 and Tb.sub.4 O.sub.7), thorium oxide (ThO.sub.2), 
thulium oxide (Tm.sub.2 O.sub.3), titanium oxide: (Tio, Ti.sub.2 O.sub.3, 
Ti.sub.3 O.sub.5 and TiO.sub.2), uranium oxide (UO.sub.2, U.sub.3 O.sub.8 
and UO.sub.3), vanadium oxide (VO, V.sub.2 O.sub.3, VO.sub.2 and V.sub.2 
O.sub.5), ytterbium oxide (Yb.sub.2 O.sub.3), and zirconium oxide 
(ZrO.sub.2). Useful ceramic materials also include boron carbide, 
zirconium carbide, beryllium carbide, aluminum beride, allumium carbide, 
boron carbide, titanium carbide, titanium diboride, iron carbide, iron 
nitride, barium titanate, aluminum nitride, titanium niobate, boron 
carbide, silicon boride, barium titanate, silicon nitride, calcium 
titanate, tantalum carbide, graphites, tungsten; the ceramic alloys which 
include cordierite/MAS, led zirconate titanate/PLZT, alumina-titanium 
carbide, alumina-zirconia, zirconia-cordierite/ZrMAS; the fiber reinforced 
ceramics and ceramic alloys; and glassy ceramics. 
Useful materials for fabrication of planar bodies 16 also include metals 
such as nickel, manganese, tungsten, magnesium, titanium, aluminum and 
steel plate. Illustrative of useful steels are carbon steels which include 
mild steels of grades AISI 1005 to AISI 1030, medium-carbon steels of 
grades AISI 1030 to AISI 1055, high-carbon steels of the grades AISI 1060 
to AISI 1095, free-machining steels, low-temperature carbon steels, rail 
steel, and superplastic steels; high-speed steels such as tungsten steels, 
molybdenum steels, chromium steels, vanadium steels, and cobalt steels; 
hot-die steels; low-alloy steels; low-expansion alloys; mold-steel; 
nitriding steels for example those composed of low-and medium-carbon 
steels in combination with chromium and aluminum, or nickel, chromium and 
aluminum; silicon steel such as transformer steel and silicon-manganese 
steel; ultrahigh-strength steels such as medium-carbon low alloy steels, 
chromium-molybdenum steel, chromium-nickel-molybdenum steel, 
iron-chromium-molybdenum-cobalt steel, quenched-and-tempered steels, 
cold-worked high-carbon steel; and stainless steels such as iron-chromium 
alloys austenitic steels, and chromium-nickel austenitic stainless steels, 
and chromium-manganese steel. Useful materials also include alloys such a 
manganese alloys, such as manganes aluminum alloy, manganese bronze alloy; 
nickel alloys such as, nickel bronze, nickel cast iron alloy 
nickel-chromium alloys, nickel-chromium steel alloys, nickel copper 
alloys, nickel-molybdenum iron alloys, nickel-molybdenum steel alloys, 
nickel-silver alloys, nickel-steel alloys; 
iron-chromium-molybdenum-cobalt-steel alloys; magnesium alloys; aluminum 
alloys such as those of aluminum alloy 1000 series of commercially pure 
aluminum, aluminum-manganese alloys of aluminum alloy 300 series, 
aluminum-magnesium-manganese alloys, aluminum-magnesium alloys, 
aluminum-copper alloys, aluminum-silicon-magnesium alloys of 6000 series, 
aluminum-copper-chromium of 7000 series, aluminum casting alloys; aluminum 
brass alloys and aluminum bronze alloys. 
The shape of planar bodies 16 may vary widely. For example, planar bodies 
16 may be of regular shapes such as hexagonal, triangular, square, 
octagonal, trapezoidal, parallelogram and the like, or may be irregular 
shaped bodies of any shape or form. In the preferred embodiments of this 
invention, planar bodies 16 are regular shaped bodies, irregularly shaped 
bodies or combination thereof which completely or substantially completely 
(at least 90% area) cover the surface of fibrous layer 14. In the more 
preferred embodiments of the invention, planar bodies 16 are of regular 
shape (preferably having truncated edges), and in the most preferred 
embodiments of the invention planar bodies 16 are triangular shaped bodies 
(preferably right angle triangles, equilateral triangles or a combination 
thereof and more preferably equilateral triangles) as depicted in FIGS. 5 
and 6, or a combination of triangular shaped bodies and hexagon shaped 
bodies as depicted in FIGS. 7 and 8, which provide for relative improved 
flexibility relative to ballistic articles having planar bodies 16 of 
other shapes of equal area. 
The number of layers 12 included in article 10 of this invention may vary 
widely depending on the use of the composite, for example, for those uses 
where article 10 would be used as ballistic protection, the number of 
layers 12 would depend on a number of factors including the degree of 
ballistic protection desired and other factors known to those of skill in 
the ballistic protection art. In general for this application, the greater 
the degree of protection desired the greater the number of layers 12 
included in article 10 for a given weight of the article. Conversely, the 
lesser the degree of ballistic protection required, the lesser the number 
of layers 12 required for a given weight of article 10. 
As depicted in the FIGS. 3 and 4, article 10 preferably includes at least 
two layers 14 in which each layer 14 is partially covered with planar 
bodies 16, preferably forming an alternating pattern of covered areas 28 
and uncovered areas 30. These layers are positioned in article 10 such 
that uncovered areas 30 of one layer 14 are aligned with covered areas 28 
of another layer 14 (preferably an adjacent layer) providing for partial 
or complete coverage of uncovered areas 30 of one layer 14 by covered 
areas 28 of another layer 12 and vice versa. Alternatively, another 
preferred embodiment includes a layer 14 in which each side of the layer 
is partially covered with bodies 18 where the bodies are positioned such 
that covered areas 28 on one side of layer 14 are aligned with uncovered 
areas 30 on the other side of layer 14. In the preferred embodiments of 
the invention the surface of layer 14 covered with planar body 16 such 
that the bodies are uniformly larger than uncovered mated areas 30 of the 
other layer 14 providing for complete overlap. This is preferably 
accomplished by truncation of the edges of the bodies 18 or otherwise 
modification of such edges to allow for close placement of the bodies on 
the surface such that a covered area is larger than the complementary 
uncovered area. 
The articles of this invention may be fabricated through use of 
conventional techniques. For example, bodies 16 may be sewn to layer 12 
using conventional sewing techniques, preferably at one or more points of 
body 16, more preferably a distance from the edge of a body 16 as depicted 
in FIGS. 4, 5 and 12. By sewing a distance from the edge of body 16 
flexibility is enhanced. To prevent extensive disalignment between various 
layers 12 adjacent layers can be stitched together. 
The thread used to stitch bodies 16 to substrate layers 14 can vary widely 
and depends on the needs of the particular situation. For example, thread 
may be formed from polymers having relatively high tensile modulus and 
tensile strength and polymers having relatively low tensile modulus and 
tensile strength. Thread is preferably a relatively high modulus (equal to 
or greater than about 200 grams/denier) and a relatively high tenacity 
(equal to or greater than about 15 grams/denier) fiber. All tensile 
properties are evaluated by pulling a 10 in. (25.4 cm) fiber length 
clamped in barrel clamps at 10 in/min (25.4cm/min) on an Instron Tensile 
Tester. In the preferred embodiments of the invention, the modulus of the 
fiber is from about 400 to about 3000 grams/denier and the tenacity is 
from about 20 to about 50 grams/denier, more preferably the modulus is 
from about 1000 to about 3000 grams/denier and the tenacity is from about 
25 to about 50 grams/denier; and most preferably the modulus is from about 
1500 to 3000 grams/denier and the tenacity is from about 30 to about 50 
grams/denier. Useful threads and fibers may vary widely and include those 
described herein below in the discussion of fiber for use in the 
fabrication of substrate layers 12. However, the thread or fiber used in 
stitching means is preferably an aramid fiber or thread (as for example 
Kevlar.RTM. 29, 49, I29 and 141 aramid fiber), an extended chain 
polyethylene thread or fiber (as for example Spectra 900 fiber and 
Spectra.RTM. 1000 polyethylene fiber) or a mixture thereof. 
The composites of this invention can be used for conventional purposes. For 
example, such composites can be used in used in any construction where 
flexibility is required, and where areal coverage by rigid bodies is 
required to provide a desirable benefit but are not flexible enough to be 
used as a single sheet. Such application include composites for control of 
transmission, absorption, reflection, and deflection of electromagnetic 
radiation(i.e. radio, infrared, visible, UV, X-ray and the like), 
acoustical energy, flames, fluids (i.e. gases and liquids), and solids. 
Other uses of the composite of this invention are in the fabrication of 
flexible insulating materials such as blankets, clothing, sleeping bags, 
tarps, tents, personal floatation gear, and the like; backing material to 
reduce blunt trauma from impact with hard objects such as bullets, 
baseballs, hockey pucks and the like; vehicle panelling and the like; and 
protective apparel and equipment such as that for protection against wild 
animals, protection for motorcyclists and for personnel working with 
dangerous equipment(i.e. meat cutters, timber cutters and the like 
),blankets for moving furniture, wet suits for scuba divers, bomb blankets 
;and the like. Still other applications include use in accessorizing 
clothing for example designs for changing the visibility of the wearer. 
In the preferred embodiments of the invention, the composites are used in 
the fabrication of penetration resistant articles of manufacture. Such 
penetration resistant articles include meat cutter aprons, protective 
gloves, boots, tents, fishing gear and the like. 
The composites of this invention are particularly useful as a "bulletproof" 
vest material or ballistic resistant articles such as "bulletproof" lining 
for example, or a raincoat because of the flexibility of the article and 
its enhanced ballistic resistance. 
In ballistic studies, the specific weight of the shells and plates can be 
expressed in terms of the areal density (ADT). This areal density 
corresponds to the weight per unit area of the ballistic resistant armor. 
In the case of filament reinforced composites, the ballistic resistance of 
which depends mostly on filaments, another useful weight characteristic is 
the filament areal density of the composite. This term corresponds to the 
weight of the filament reinforcement per unit area of the composite (AD). 
The following examples are presented to provide a more complete 
understanding of the invention and are not to be construed as limitations 
thereon. 
EXAMPLE 1 
A. General Procedure 
I. Composite Panel Preparation 
The metal-fabric composite panels were 15 inches (38 cm) square and 
prepared by sewing the appropriate equilateral triangular 0.05 inch (0.127 
cm) thick aluminum assemblies onto a five layer fabric panel. A plain 
weave ballistic nylon fabric (style 000-26042 from Burlington Industries), 
having 33.times.33 yarns per inch (13.times.13 yarns/cm) and layer areal 
density of 0.27 km/m.sup.3) was marked with an equilateral triangular grid 
having 3 inch (7.6 cm) side length. For all triangular assemblies, 
originally having side lengths of 3 inches, (7.6 cm) small triangles were 
cut off the aluminum metal apexes corresponding to the grid apexes (the 
height of these small triangles was 0.2 inches (0.51 cm)). The triangular 
assemblies were sewn onto the fabric panels through eyes 24 in the pattern 
shown in FIG. 26, with one half of the triangles on each side of the 
fabric panel. 
Elastomeric thread was used to hold metal sub-units together as required. 
SPECTRA.RTM. 1000 sewing thread was used to affix the triangular assembly 
onto the fabric layers. 
B. Composite Panels 
1. SAMPLE 1 
This sample consisted of an assembly of unhinged aluminum triangles 16 as 
shown in FIG. 30. This construction provides three sets of parallel seams 
along which the hybrid panel can flex with seam distance being 2.6 inches 
(6.6 cm). 
2. SAMPLE 2 
This sample consisted of an assembly of aluminum triangles 16 having one 
hinge 32 per triangle 16, as shown in FIG. 29, which hinge is formed by 
tying triangular sub-unit 62 and trapezoidal sub-unit 64 together by 
elastomeric thread 66. This construction provides three sets of parallel 
seams distances in two directions being 2.6 inches (6.6 cm) in one 
direction and in the other direction being 1.3 inches (3.3 cm). 
3. SAMPLE 3 
This sample consisted of an assembly of aluminum triangles 16 having two 
hinges 32 and 68 per triangle, as shown in FIG. 28, which hinges are 
formed by tying triangular sub-units 70 and 72 and parallelgram sub-unit 
58 together by elastomeric thread 66. 
4. SAMPLE 4 
This sample consisted of an assembly of aluminum triangles 16 having three 
hinges 32, 68 and 74 per triangle 16, as shown in FIG. 27 which hinges are 
formed by tying triangular sub-units 76, 78, 80 and 82 together by 
elastomeric thread 66. This construction provides three sets of parallel 
seams along which the hybrid panel can easily flex with seam distance in 
all three directions being 1.3 inches (3.3 cm). 
II. FLEXIBILITY EVALUATION 
The flexibility of SAMPLES 1 to 4 was judged in three different directions 
using the procedure of Drape Test 3 by determining if the panel can be 
wrapped around a cylinder having an outside diameter of 3 inches (7.6 cm). 
The results, summarized in Table 1, indicate control of flexibility which 
can be achieved by varying the number of hinges. 
TABLE 1 
______________________________________ 
FLEXIBILITY OF PANELS WITH ALUMINUM PLATE 
SEWN ONTO FABRIC DRAPE TEST 1 
SAMPLE NO. OF 
NO. HINGES 0.degree. 
60.degree. 
120.degree. 
______________________________________ 
1 0 NO NO NO 
2 1 YES NO NO 
3 2 NO YES YES 
4 3 YES YES YES 
______________________________________ 
EXAMPLE 2 
The flexibility of the composite of this invention having hinged triangular 
bodies was evaluated using the procedures of Drape Test 1 and Drape Test 2 
in comparison with other composites. The composites selected for 
evaluation were composite SAMPLE 5 which had unhinged triangular bodies of 
FIG. 30 on the same side of the fabric layer, and composite SAMPLE 6 which 
was essentially identical to SAMPLE 5, except that hinged triangular 
bodies depicted in FIG. 27 were used. SAMPLES 5 and 6 were constructed 
like SAMPLES 1 and 4, respectively, except that all metal triangles were 
attached to on side of the fabric. 
The results are set forth in the following the Tables 2 and 3. 
TABLE 2 
______________________________________ 
FLEXIBILITY OF PANELS WITH ALUMINUM PLATES 
SEWN ONTO FABRIC, DRAPE TEST NO. 2 
METAL H/L AT DIFFERENT 
PLATE ORIENTATIONS 
SAMPLE NO. 
POS. 0.degree. 
30.degree. 
45.degree. 
60.degree. 
90.degree. 
______________________________________ 
1. SAMPLE 6 
TOP 0.91 0.90 0.91 0.93 0.86 
BOTTOM 0.80 0.75 0.77 0.84 0.70 
2. SAMPLE 5 
TOP 0.95 0.95 0.96 0.96 0.95 
BOTTOM 0.90 0.88 0.85 0.94 0.87 
______________________________________ 
TABLE 3 
______________________________________ 
FLEXIBILITY OF PANELS WITH ALUMINUM PLATES 
SEWN ONTO FABRIC, DRAPE TEST NO. 2 
SAMPLE NO. METAL PLATE POSITION 
H/L 
______________________________________ 
1. Sample 6 Top 0.33 
Bottom 0.23 
2. Sample 5 Top 0.85 
Bottom 0.48 
______________________________________ 
EXAMPLE 3 
Two 14 inch (35.6 cm) square panels were prepared by sewing 3 inch (7.6 cm) 
square hinged assemblies of 0.05 inch (0.127 cm) thick aluminum plates 
between two Nylon fabric layers (Burlingston Industries, Style 00-26042, 
33.times.33 yarns per inch (13.times.13 yarns/cm), AD=0.27 kg/m.sup.2). 
Both panels consisted of 16 hinged assemblies sewn between the two fabric 
layers in a square area filling pattern. The hinged assembly incorporated 
into panel 1 consistent of four 1.5 inch (3.8) squares aluminum plate 
hinged together using an adhesive tape. The hinged assembly for Panel 2 
were prepared in the same manner except four right angle isosceles 
triangles having hypotenuse length of 3 inches (7.6 cm) were assembled to 
create the 3 inch (7.6 cm) square assembly. 
The flexibility of these two panels was determined using Drape Test 1. The 
results, given in Table 4 and shown in FIG. 31. 
TABLE 4 
______________________________________ 
FLEXIBILITY OF HINGED ASSEMBLIES 
RATIO H/L 
ANGLE (degrees) Panel 1 Panel 2 
______________________________________ 
0 0.99 1.0 
30 0.58 0.78 
45 0.51 0.99 
60 0.59 0.81 
90 0.99 1.0 
______________________________________ 
The results illustrate that a much more flexible structure is achieved 
using the structure based on the triangular aluminum plates compared to 
the structure based on the aluminum squares. Note that the hinged 
assemblies which were sewn between the two fabric layers were identical in 
size and that the only difference was the shape of the individual plates 
used to create the assemblies.