Ballistic shield composites with enhanced fragment resistance
View Patent ↗Consolidated, layered composites having high penetration resistance to both bullets and fragments are described. The composites comprise, in order, a first non-woven fabric comprising one or a plurality of unidirectionally oriented high tenacity fibrous layers, a felt material comprising high tenacity felt fibers, and a second non-woven fabric comprising one or a plurality of unidirectionally oriented high tenacity fibrous layers. The non-woven fabrics and intermediate felt material are consolidated at facing lateral surfaces.
1. A consolidated, layered composite having high penetration resistance to both bullets and fragments, comprising, in order:
(a) a first non-woven fabric comprising one or more unidirectionally oriented high tenacity fibrous layers,
(b) a felt material comprising high tenacity felt fibers, and
(c) a second non-woven fabric comprising one or more unidirectionally oriented high tenacity fibrous layer.
2. The composite of claim 1 , wherein the fibrous layers of the first and second non-woven fabrics comprise high tenacity fibers in a resin matrix.
3. The composite of claim 2 , wherein the resin matrix of the first and second non-woven fabrics independently comprises a resin selected from the group consisting of a thermoplastic resin, a thermosetting resin, and a hybrid resin.
4. The composite of claim 3 , wherein the resin matrix of the first and second non-woven fabrics is present in an amount from about 5% to about 40% by weight of the first and second non-woven fabrics, respectively.
5. The composite of claim 2 , wherein the high tenacity fibers of the first and second non-woven fabrics independently comprise polyolefin fibers or aramid fibers.
6. The composite of claim 5 , wherein the high tenacity fibers of both the first and the second non-woven fabrics comprise polyethylene fibers.
7. The composite of claim 6 , wherein the plurality fibrous layers of both the first and second non-woven fabrics are in a cross-ply arrangement of unidirectionally oriented fibers with adjacent layers of fibers extending in a direction of 90° relative to one another.
8. The composite of claim 7 , wherein the first and second non-woven fabrics comprise from 2 to 8 fibrous layers.
9. The composite of claim 1 , further comprising a nitrile rubber polymer disposed on the high tenacity fibers of the felt material.
10. The composite of claim 9 , wherein the nitrile rubber polymer is present in the felt material in an amount from about 2% to about 50% by weight.
11. The composite of claim 1 , further comprising (i) a first laminating film layer between the first non-woven fabric and the felt material and (ii) a second laminating film layer between the felt material and the second non-woven fabric, wherein the first and second laminating film layers are each present in an amount of from about 5% to about 25% by weight of the felt material.
12. The composite of claim 11 , wherein the felt material comprises a single felt layer disposed between the first and second laminating film layers.
13. The composite of claim 11 , wherein the felt material comprises a plurality of felt layers separated by felt laminating layers, wherein the plurality of layers is disposed between the first and second laminating film layers.
14. The composite of claim 1 , wherein the composite is resistant to a rifle bullet having an energy from about 400 J (295 ft-lb) to about 4000 J (2950 ft-lb) and a fragment having an energy from about 400 J (295 ft-lb) to about 4000 J (2950 ft-lb).
15. The composite of claim 1 , having a total thickness of less than about 12 mm (0.47 in) and a total areal density of less than about 8 lb/ft 2 (39.2 kg/m 2 ).
16. A vest having high penetration resistance to both bullets and fragments comprising the composite of claim 1 .
17. A method of making a layered composite, the method comprising consolidating
(a) a first non-woven fabric comprising one or more unidirectionally oriented high tenacity fibrous layers,
(b) a felt material comprising high tenacity felt fibers,
(c) a second non-woven fabric comprising one or more unidirectionally oriented high tenacity fibrous layers,
optionally together with a laminating film layer between (a) and (b) and/or a laminating film layer between (b) and (c), to provide the layered composite.
18. The method of claim 17 , wherein the consolidating occurs at a temperature in the range from about 75° C. to about 150° C. and a pressure in the range from about 1 barg (15 psig) to about 14 barg (203 psig).
19. The method of claim 17 wherein, during the consolidating, the felt material is compressed and has a thickness, in the layered composite, that is reduced by at least about 10%, relative to an initial thickness prior to consolidating.
20. An article having high penetration resistance to both bullets and fragments, the article comprising a consolidated, layered composite comprising a felt material comprising high tenacity felt fibers having a nitrile rubber polymer disposed thereon in an amount from about 2% to about 50% by weight, and further comprising first and second non-woven fabrics adjacent each opposing lateral surface of the felt material,
wherein the first and second non-woven fabrics each comprise one or more high tenacity fibrous layers in a cross-ply arrangement of unidirectionally oriented fibers with adjacent layers of fibers extending in a direction of 90° relative to one another, wherein the felt material and non-woven fabrics are consolidated at facing lateral surfaces.