CA2292943C

CA2292943C - Protective boot and sole structure

Info

Publication number: CA2292943C
Application number: CA 2292943
Authority: CA
Inventors: Guy Andrew Vaz
Original assignee: BFR Holdings Ltd
Current assignee: BFR Holdings Ltd
Priority date: 1998-12-29
Filing date: 1999-12-22
Publication date: 2009-09-15
Anticipated expiration: 2019-12-22
Also published as: US20020011146A1; DE69910724T2; NZ502095A; US20020011011A1; SG126668A1; US6461673B1; CA2292943A1; EP1016355A2; US6425193B2; AU6545899A; EP1016355B1; AU765430B2; EP1016355A3; EP1405577A3; EP1405577A2; DE69910724D1

Abstract

A sole for a boot and the boot incorporating the sole. The sole provides the wearer of the boot with a level of protection from explosive devices triggered by the wearer stepping on or near the explosive device. The sole includes at least one layer of corrugated blast-resistant material. The corrugations provide channels that effectively channel blast gases generated by the explosion of the explosive device sidewardly and so away from the foot of the wearer of the boot. The sole further includes layers of blast-resistant material and a cocoon of material is also provided throughout the upper of the boot to provide a level of protection to the remainder of the wearer's foot.

Description

Protective boot and sole structure Field of the Invention The present invention relates to footwear and in particular to a boot that is constructed to protect the foot of a wearer from serious damage resulting from the impact of a projectile and/or explosions from anti-personnel mines inadvertently detonated by the boot wearer. The present invention is also directed to a material that can be used, in one application, in the footwear described in the present application.
Background to the Invention Anti-personnel mines which are designed to explode as a person steps on or near the mine represent a common and serious problem for any troops deployed either on a conventional battle field or involved in guerilla warfare.
The amount of explosive present in a mine will dictate whether the mine on exploding maims or kills the person triggering the mine. For those devices designed simply to maim, protective footwear can play a role in lessening the likelihood of serious injury. Such footwear can also have a role in lessening the damage caused by the impact of projectiles such as bullets and shrapnel.
The present inventor has developed boots, and in particular boot soles, that can afford a level of protection to the foot of a person triggering an anti-personnel mine containing reasonable quantities of explosive while still providing the wearer with sufficient toe-to-heel flexion in the boot to allow activities such as running, jumping and climbing (see WO 96/26655, DE 2615558 and WO 97/43919).
The present invention is directed to a new type of boot structure that offers an improved level of protection to wearers that may inadvertently trigger an anti-personnel mine.
Summary of the Invention According to a first aspect, the present invention comprises a sole for an article of footwear, the sole including at least one corrugated layer of a substantially blast and/or fragment resistant material.
In one embodiment, the corrugated layer is only present in the heel of the sole.
In another embodiment, the corrugated layer can be present in the portion of the sole extending forwardly from the heel or the fore portion. In a still further embodiment, the corrugated layer can extend across a substantial portion of or the entire sole. The corrugated layer is preferably formed in the sole such that the corrugations extend transversely to the longitudinal axis of the sole. In a further preferred embodiment, each of the corrugations are preferably at about a riglit angle to the longitudinal axis of the sole.
The conrugated layer can be formed in the sole with a planar layer formed from the blast and/or fragment resistant material disposed on the upper and/or lower sides of the corrugated layer. Preferably, the planar layer can be disposed on the upper and/or lowec- sides of the corrugated layer such that it meets the peaks of some or each of the corrugations of the corrugated layer. The planar layer on the upper and/or lower sides of the corrugated layer, can be formed integrally witli the conugated layer or brought into fixed attaclunent with the corrugated layer. Where a planar layer is, disposed on at least one of the upper or lower sides of the corrugated layer, at least a first set of a plurality of channels are formed in the sole. The present inventor has determined that these cliannels are surprisingly effective in channelling blast gases, generated when a mine is triggered, laterally away from the foot of the wearer.
In one einbodiment of the invention, the sole can liave at least one corrugated layer in botll ttie heel and the fore portion extending forwardly fronl the lieel, with the respective corrugated layers in the lieel and fore portions being formed from different materials.
The cocrugated layer and planar layers disposed on the upper or lower sides of the corrugated layer can be fonned from a metal-matrix composite material. The composite can be fonned from woven or chopped graphite, a ceramic material or a combination of sucli materials. In a preferred embodiment, it is formed from woven graphite (ie carbon fibre) of the type 3K TOW, 380g/m', M60/T300 that has been impregnated with a polyiner containing a metal powder. The polymer can comprise either a polymer solution or molten polymer, witll the metal being a metal alloy. The metal alloy can constitute at least 20% w/w of the polymer. Examples of the metal powder include aluminium alloys, such as an alloy of aluminium, nickel and molybdenum.
To form the composite, the woven graphite can be passed through a drier (such as an electric fucnace) and then through a batli of molten alloy which fully wets the fabric. In a preferred embodiment, the molten alloy is a molten aluminium alloy of aluminiutn, nickel and molybdenum. As the woven graphite passes tlu-ough the molten alloy, the polymer carburises between SO0 C and 600 C and a chemical bond is created between the graphite fibres and the metal. The metal matrix composite is tllen passed tluougli a set of rollers that are capable of exerting about 35 to 40 tons of compressive force and which squeeze out all excess metal alloy fronl the composite. The result is a coniposite material impregnated with metal.

The metal powder added to the polymer impregnating the woven graphite can also include titaiiium and nickel alloys. In this case, up to 50% w/w of the metal powder can be added to the molteu polymer. By using such nletal powders, the step of passing the impregnated woven graphite through the batli of molten alloy can be discarded. Instead, the woven graphite can be simply passed through the drier and then through the rollers.
Other metals, such as titanium, beryllium and metal alloys of various types can then be applied to the material to provide excellent bonding of the material.
The other metals can also be applied by processes such as plasma spraying or hot sheet pressing.
In an altecnative embodiment, the comlgated layer and planar layers disposed on the upper and/or lower sides of the corrugated layer can be formed from a polymer inipregnated or an epoxy resin impregnated composite.
In a preferred embodiment of the invention, the sole includes a heel plate including a first upper portion of one or more, and preferably tliree, layers of woven aramid fibre. The woven aramid layers can eacli be formed from 280g/m2 woven aramid. During t[le manufacturing process for the sole, the layers of woven aramid fibre are preferably held together by a porous coat of adhesive, sucli as hot melt polyuretliane adhesive. In the heel plate, the corrugated layer preferably does not extend outwardly to the periphery of the first upper portion of one or more layers of woveii aramid fibre. Rather, it preferably exteuds to a position inwardly from the periphety with the distance or gap between the periphery of the inner portion and the corrugated layer being substantially identical about the peripliery of the heel plate. In one particularly preferred embodiment, the distance between the periphery of the first upper portion and the periphery of the corrugated layer is about 7mm. As an example only, the material forming the corrugated layer in the heel portion can have a thickness of about 0.38mm, with the corrugations having a height of about 4.5nun and a peak to peak spacing of about 2mm.
In a further embodiment, the sole includes a flexible fore plate disposed in the fore portion of the sole. The fore plate preferably includes a first upper portion of one or more, and preferably tlu-ee, layers of woven aramid fibre. Again, the woven aramid layers can eacli be formed from 280g/mZ woven aramid. During the manufacturing process for the sole, the layers of woven aramid in the first upper portion of the fore plate are also preferably held together by a porous coat of adliesive, such as hot melt polyuretliane adliesive.
In the case of the fore plate, the con-ugated layer is preferably positioned in the fore plate immediately below the first upper pottion and comprises a layer of corrugated polymer impregnated composite. The corrugated layer preferably does not extend to the periphery of the first upper portion of one or more layers of woven aramid fibre. Rather, it preferably extends to a position inwardly from the peripliery with the distance or gap between the peripliery of the first upper portion and the periphery of the corrugated layer being substantially identical about the peripliery of the fore plate. In one particularly preferred embodiment, the distance between the periphery of the first upper portion and the peripliery of the corrugated layer is about 7mm. The polymer impregnated composite can comprise two layers of woven aramid and, more preferably, two layers of 280g/m' scoured Twaron. To form this conlposite, the woven fabric is impregnated with a polymer solution. The fabric is then preferably passed tlirougli a drier, and then through a bath of molten nylon wllich wets the fabric completely.
Ultrasonic vibrators can be used to vibrate the molten nylon as the fabric is passed therethrough. The composite is then passed between two rollers that exert at least several tons of compression on the fabric to squeeze out excess polytner from the composite. It is preferred that the resulting polyiner impregnated conlposite contains less than 30% w/w of polymer.
The corrugated impregnated polymer composite layer in the fore plate is preferably adhered with epoxy resin to the first upper portion of one or more layers of woven aramid. In addition, the coniposite layer can be stitclied to the first upper portion. As an example only, the material fonuing the corrugated layer in the fore plate can liave a wall tllickness of about 0.4uim, witli the corrugations having a heiglit of about 4.5mm and a peak to peak spacing of about 2mm.
The sole according to the present invention is adapted to be part of an article of footwear, such as a boot worn by infantry troops in combat zones.
According to a second aspect, the present invention comprises a blast-resistant sole for an article of footwear adapted to offer a level of protection to the foot of the wearer of the footwear if the wearer inadvertently triggers an explosive device, the sole having a longitudinal axis and including a plurality of channels extending transversely to the longitudinal axis, eacli of the channels being adapted to channel blast gases, generated wlien the explosive device is triggered, laterally away from the foot of the wearer.
In tliis second aspect, the plurality of cliannels can be formed by the provision of at least one corrugated layer of blast-resistant material as described herein.
In eacli of the above aspects, the boot preferably further includes a cocoon of substantially blast-resistant material that is incorporated into the boot. The cocoon is preferably adapted to substantially or entirely suiround the foot of a wearer of the boot.

The cocoon can be integrated witliin the upper of the boot or comprise the upper. In a preferred embodiment, the upper is preferably formed from a natural or synthetic leather outer layer and an inner vamp layer of leather or cotton between which the cocoon is positioned. The cocoon is preferably formed from one or more layers of 5 blast-resistant material. In one embodiment, the cocoon can include at least two layers of woven aramid. The woven aramid can be 450g/m2 ZyPhir material made for ZyPhir Research by Akzo-Nobel Twaron. The layers of woven aramid of the cocoon can also be stitched together with aramid fibre (sucli as ZyPhir 210 thread) to form an integrated protective and supportive cocoon. The layers of woven aramid are also preferably bonded with polyurethane Ilot nielt adhesive that is applied as a porous coating. The result preferably is a material for the cocoon that is water-resistant yet breathable. In a specific application, a soft and pliable polyurethane hot melt is applied as a coating between the at least two layers of aramid. The polyuret(lane hot melt can be applied in a layer of about 0.05mm. This embodiment of the boot lias particular application in cold climates but could be used in warmer conditions.
In another embodiment, the cocoon can comprise a sandwich of layers of woven ceramic fibres or woven ceranlic/glass-ceranlic composite fibres and aramid fibres.
The sole according to the present invention is preferably stitched about its periphery to the cocoon. Wliere there is a distance or gap between the periphery of the con-ugated layer and the periphery of the inner portion, the stitcliing betNveen the sole and the cocoon preferably is made outside the peripliery of the corrugated layer.
The sole according to the present invention preferably also includes an additional layer of blast-resistant material disposed between the lower surface of the cocoon and the at least one corrugated blast-resistant layer included in the sole. The additional layer is preferably comprised of a plurality of layers of woven aramid fibre.
In a particularly preferred embodiment, the additional layer can comprise at least fifteen layers of woven aramid fibre. The woven aramid fibre can comprise 200g/m2 ZyPhir mater-ial that is made for ZyPhir Research by Akzo-Nobel Twaron. Preferably, each layer of woven aramid is bonded togetlier with a fine spray of hot melt polyurethane adhesive. The polyurethane adliesive is preferably applied as a porous coating of about 5g of polyurethane per square metre of woven aramid.
The sole according to the present invention preferably includes a still further layer of blast-resistant material disposed between the additional layer and the at least one coirugated blast-resistant layer included in the sole. The still further layer can be fonned from at least one layer of woven aramid and at least one layer of woven ceramic fibre. It is particularly preferred that a woven ceramic fibre layer is the outenuost or bottommost layer of the still further layer of blast-resistant material. It is further preferred that tlie still further layer includes a plurality of layers of woven aramid and woven ceramic fibre, witli the aramid and ceramic fibre layers being layered in alternating sequence. Again, it is preferred that the ceramic fibre layer be the outerenost or bottomniost layer of the still further layer. In one enlbodiment, as an example only, the still further layer can include two layers of woven aramid fibre interleaved with two layers of woven ceramic fibre, again witli one of the woven ceramic layers being the outermost or bottommost layer. The woven aramid fibre can be formed from 280g/m2 aramid in this exanlple. In still otlier embodiments, some or each of the layers of woven ceramic fibre can be replaced witli woven ceramic/glass-ceramic composite fibres.
The sole preferably includes an outermost ground-engaging layer. This layer is preferably fonned from rubber or polyurethane. In the case of the rubber sole it can be vulcanised onto the boot. The ground-engaging layer can be fonned in at least two layers, an outennost layer and an inner layer. The outennost layer can comprise a nitrile rubber and the inner layer can be fornled of a foani rubber. The nitrile rubber can have a specific gravity of 1.6 and a Shore A liardness of 85. The nitrile rubber layer can be about 3mm. The foanl rubber layer can have a specific gravity of 0.6 and a Shore A liardness of 40. The foam rubber layer provides a greater level of comfort to the wearer of the footwear tlian if the outennost layer was formed entirely of nitrile rubber as described.
Brief Description of the Drawings By way of example only, a preferred embodiment of the invention is now described with reference to the accompanying drawings, in which:
Fig. I is a simplified cross-sectional view of a boot having a sole according to the present invention;
Fig. 2 is an inverse plan view of the fore plate and blast shield used in the sole according to the present invention;
Fig. 3 is an exploded vertical cross-sectional view of components of the boot and sole depicted in Fig. 1;
Fig. 3a is an enlarged view of the corrugated layer in the fore plate of the sole according to the present invention;
Fig. 3b is an enlarged view of the corrugated layer in the lieel of the sole according to the present invention; and Fig. 4 is a cross-sectional view of the lieel of the sole along line IV-IV of Fig. I
according to the present invention.

Preferred Mode of Canying Out the Invention A boot having the features of the present invention is generally depicted as 10 in Fig. 1. Explosive devices that are hidden in the ground and adapted to be exploded by the weiglit of a person walking on or near the ground wliere the device is buried are generally called mines. The damage that can be caused by a mine is dependent on the type and quantity of the explosive used in the nline. While mines can obviously kill, the purpose of many mines is to only maim the person wlio is unfortunate to trigger the device. The boot having the features of the present invention is designed to be woni by infantry soldiers or others moving tlirougli areas wliere mines are known or possibly hidden. Wliile no fonn of wearable protection can protect against all devices that are desigiied to cause large explosions, the present invention does offer a level of protection that is designed to protect the foot of the soldier from serious damage, such as loss of a foot, if the soldier triggers a mine having a type or quantity of explosive that would maim a person wearing normal footwear.
The boot 10 has a substantially standard shaped upper 11 adapted to enclose the foot and ankle of a wearer and a sole 12. The sole 12 conlprises a lieel 13 and a fore plate region 14 that extends from a position distal the heel 13 to the toe 15 of the boot 10.
The lieel 13 includes at least one con-ugated layer of inetal-niatrix composite niaterial 16 that extends in a plane tlirougliout at least a nlajority of the heel 13.
Disposed inunediately above and below the con-ugated layer 16 is at least one layer of planar metal-matrix composite 17. The combination of the corrugations in the corrugated layer 16 and the respective planar layers 17 defines a plurality of cliannels 18 that extend transversely across the heel 13. The channels 18 serve to cllamlel laterally blast gases generated by the explosion of a mine beneatli the boot sidewardly and so serve to provide a level of protection to the foot of the wearer in the boot 10 above the corrugated layer 16.
In the depicted embodiment, the nietal-matrix composite is fornled from woven graphite (preferably, of the type 3K TOW, 380g/mZ, M60/T300) impregnated with a polymer containing a nletal powder of an alloy including aluminium, nickel and molybdenum.
The composite is formed in a metllod including the steps of:
impregnating the grapliite with the polymer containing the metal alloy powder;
drying the grapliite in a drier;
passing the graphite tllrough a molten batli of an aluminium/nickel/molybdenum alloy that is at a temperature to carburise the polymer; and s exerting a pressure on the composite to renlove ttle excess metal alloy tlierefrom.
The step 6f exerting pressure on the composite is aclueved by passing the composite tluougli a set of rollers that are capable of exerting about 35 to 40 tons on the composite.
It will be realised that corrugated layers of otlier materials could be utilised in the sole of the present invention. For example, a polynler impregnated composite or an epoxy impregnated coinposite could be utilised in certain situations as the corrugated layer in the heel of the sole.
Disposed above the conugated layer 16 in the lieel 13 is an upper layer 19 of blast-resistant material which in the depicted enibodiment comprises tluee layers of woven aramid fibre that extend substantially to the periphery of the heel 13.
In the depicted embodiment, the three layers of aramid are each fonned from 280g/m2 woven aramid lield togetlier by a porous coat of liot melt polyuretliane adhesive.
In the depicted enlbodiment, the coi-rugated layer 16 does not extend laterally as far as the upper layer 19. Rather. a gap is left about the entire periphery of the heel 13.
The fore plate 14 is resiliently flexible and includes at least one corrugated layer of polymer iuipregnated composite material 21 that extends througliout at least a nlajority of the fore plate 14. Disposed immediately above the corrugated layer 21 is at least one layer of non-corrugated polymer inipregnated composite 22. The combination of the corrugations in the con-ugated layer 21 and the non-coirugated layer 22 defines a plurality of channels 23 that extend transversely across the fore plate 14.
The cllannels 23 serve to cliannel laterally blast gases generated by the explosion of a mine beneatti the boot 10 sidewardly and so seive to provide a level of protection to the foot of the"
wearer in the boot 10 above the corrugated layer 21.
Disposed above the coirugated layer 21 and non-corrugated layer 22 in the fore plate 14 is au upper layer 24 of blast-resistant material wliich in the depicted embodinlent comprises three layers of woven aramid fibre that extend substantially to the periphery of the fore plate 14. In the depicted embodiment, the three layers of aramid are each formed from 280g/mz woven aramid held togetlier by a porous coat of hot melt polyurethane adhesive. In the depicted embodiment, the corrugated layer 21 does not extend laterally as far as the upper layer 24. Ratlier, a gap is left about the entire periphery of the fore plate 14. While the coirugated layer in the fore plate 14 is adhered to the upper layer 24 using an epoxy adhesive, stitching can also be used to strengthen the adherence of the layers 21, 22 and 24 togetlier in the fore plate 14.
The sole 13 further includes a ground engaging layer 25. The layer 25 in the depicted embodiment is formed from rubber and has been vulcanised to the remainder of the sole. The layer 25 has a tread 26 that allows the wearer to walk across ground surfaces likely to be encountered by the wearer. In the depicted embodiment, and as is depicted in Fig. 4, the layer 25 includes an outer layer 27 and an inner layer 28. The outer layer 27 is fonned from a nitrile rubber wliile the inner layer 28 is formed from a softer foam rubber. In the depicted embodiment, the nitrile rubber has a specific gravity of 1.6, a Shore A hardness of 85, and a tliickness of about 3mm. The foam rubber, which provides a greater level of comfort to the wearer, has a specific gravity of 0.6 and a Shore A hardness of 40.
The boot 10 also includes a cocoon 29 of substantially blast-resistant material that is incorporated into the boot 10 and which is adapted to entirely surround the foot of a wearer of the boot 10. In the depicted embodiment, the cocoon 29 is formed from two layers of woven araniid fibre (see Fig. 4) that extend across the sole 13 of the boot and also up witliin the upper I 1 of the boot 10. As is depicted in Fig. 1, the cocoon 29 is disposed between a cotton vanip 31 and the leather outer 32 in the upper 11. As is depicted in Fig. 4, the cocoon extends beneatli a knoNvn in the art comfort sole liner 33 and the renlainder of the sole 13. The layers of woven aramid fonning the cocoon 29 are preferably boilded by liot melt polyurethane adhesive and are stitched togetlier using aramid fibre. Wllile not depicted, it can be readily envisaged that the cocoon 29 can include layers of woven ceramic fibres or woven ceramic/glass-ceramic composite fibres and woven aramid fibres.
The cocoon 29 is also stitched to the sole about the peripllery of the sole 13 to further increase adlierence of the sole 13 to the remainder of the boot 10.
An additional layer 34 of blast-resistant material is also provided in the sole 13.
In the depicted embodiment, the additional layer 34 comprises fifteen layers of woven aramid fibre. In Fig. 4, however, only four of the layers are depicted for clarity. It will be erivisaged that more or less layers could be utilised if desired. The woven aramid fibre layers are bonded together with a llot melt polyurethane adliesive.
The sole also includes a still further layer 35 of blast-resistant material or a blast shi.eld. The blast shield 35 is, in the depicted embodiment, fonned from alternating layers of woven aramid fibre and woven ceramic fibre. In the depicted embodiment, the bottommost layer 35a (see Fig. 4) of the blast shield 35 is a layer of woven ceramic fibre. It will be appreciated that in the blast sllield 35 that the woven ceramic fibre can be replaced with woven ceramic/glass-ceramic composite fibres in anotlier embodiment of the invention.
The various layers of the sole 13 ai-e preferably supported in a suitable supporting medium, such as polyurethane or rubber. It will be appreciated that suitable adhesives and stitching can be employed to form the entire boot 10 including its sole 13 and cocoon 29. A deflector plate, such as is described in the applicant's Publication No. WO/97/43919, can also be incorporated into the sole 13, if desired.
It will be appreciated by persons skilled in the art that numerous variations 5 and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A sole (12) for an article of footwear including at least one corrugated layer (16, 21) of a substantially blast resistant, fragment resistant, or blast and fragment resistant material, characterized in that at least one planar layer (17, 28) of the substantially blast resistant, fragment resistant, or blast and fragment resistant material co-operates with a corrugated layer to form a plurality of laterally extending channels (18, 23), relative to the longitudinal axis of the sole.

2. The sole of claim 1, wherein the channels are adapted to channel blast gases, generated when an explosive device is triggered, laterally away from the foot of the wearer.

3. The sole of claim 1 or claim 2, wherein the corrugated layer is only in a heel portion of the sole.

4. The sole of claim 1 or claim 2, wherein the corrugated layer is only in a fore portion of the sole.

5. The sole of claim 1 or claim 2, wherein the corrugated layer can extend across a substantial portion of the sole or the entire sole.

6. The sole according to any one of claims 1 to 5, wherein each of the channels are disposed at about a right angle to the longitudinal axis of the sole.

7. The according to any one of claims 1 to 6, wherein the planar layer is disposed on the upper side, lower side or upper and lower sides of each of the corrugated layers.

8. The sole according to any one of claims 1 to 7, wherein the planar layer is disposed on the upper side, the lower side or the upper and lower sides of the corrugated layer such that is meets the peaks of some or each of the corrugations of the corrugated layer.

9. The sole according to any one of claims 1 to 8, wherein the planar layers on the upper side, lower side or upper and lower sides of each of the corrugated layers are formed integrally with the corrugated layer or in fixed attachment with each of the corrugated layers.

10. The sole according to any one of claims 1, 2, 5, 6, 7, 8 or 9, wherein the sole can have at least one corrugated layer in both the heel portion and the fore portion of the sole.

11. The sole of claim 10, wherein the respective corrugated layers in the heel and fore portions are formed from different materials.

12. The sole according to any one of claims 1 to 11, wherein the corrugated layer is formed from a metal-matrix composite material.

13. The sole of claim 12, wherein the metal-matrix composite material is formed from woven or chopped graphite, a ceramic material or a combination of these materials impregnated with an aluminum alloy.

14. The sole according to any one of claims 1 to 11, wherein the at least one planar layer is formed from a metal-matrix composite material.

15. The sole of claim 14, wherein the metal-matrix composite material is formed from woven or chopped graphite, a ceramic material or a combination of these materials impregnated with an aluminum alloy.

16. The sole of any one of claims 1 to 11, 14 or 15, wherein the corrugated layer is formed from a polymer impregnated composite or an epoxy resin impregnated composite.

17. The sole of any one of claims 1 to 13, wherein the at least one planar layer is formed from a polymer impregnated composite or an epoxy resin impregnated composite.

18. The sole according to any one of claims 1, 2, or 5 to 17, wherein the corrugated layer in the heel potion is formed from a metal-matrix composite material and the corrugated layer in the fore portion is formed from a polymer impregnated composite or an epoxy impregnated composite.

19. The sole according to any one of claims 1 to 18, wherein the heel portion also includes a first upper portion of one or more layers of woven aramid fibre.

20. The sole of claim 19, wherein the first upper portion is comprised of three layers of woven aramid fibre.

21. The sole of claim 19 or claim 20, wherein the corrugated layer does not extend outwardly to the periphery of the first upper portion but instead extends to a position inwardly from the periphery with a gap between the periphery of the inner portion and the periphery of the corrugated layer being substantially identical about the periphery of the heel.

22. The sole of claim 21, wherein the gap between the periphery of the first upper portion and the periphery of the corrugated layer is about 7 mm.

23. The sole according to any one of claims 4 to 11 or 13 to 22, wherein the fore portion is resiliently flexible.

24. The sole of claim 23, wherein the fore portion includes a first upper portion of one or more layers of woven aramid fibre.

25. The sole of claim 24, wherein the first upper portion of the fore portion is comprised of three layers of woven aramid fibre.

26. The sole of claim 24 or claim 25, wherein the corrugated layer is positioned in the fore portion immediately below its first upper portion.

27. The sole of claim 26, wherein the corrugated layer is a layer of corrugated polymer impregnated composite.

28. The sole according to any one of claims 24 to 27, wherein the corrugated layer in the fore portion does not extend outwardly to the periphery of its first upper portion but instead extends to a position inwardly from the periphery with the gap between the periphery of the inner portion and the periphery of the corrugated layer being substantially identical about the periphery of the fore portion.

29. The sole of claim 28, wherein the gap between the periphery of the first upper portion and the periphery of the corrugated layer in the fore portion is about 7 mm.

30. The sole according to any one of claims 24 to 29, wherein the corrugated layer in the fore portion is adhered with epoxy resin to the first upper portion in the fore portion.

31. The sole according to any one of claims 24 to 29, wherein the corrugated layer is stitched to the first upper portion of the fore portion.

32. The sole according to any one of claims 1 to 31, wherein the sole includes an additional layer of blast resistant material disposed proximate the upper surface of the sole.

33. The sole of claim 32, wherein the additional layer comprises a plurality of layers of woven aramid fibre.

34. The sole of claim 32 or claim 33, wherein the additional layer comprises at least fifteen layers of woven aramid fibre.

35. The sole according to any one of claims 32 to 34, wherein the sole includes a still further layer of blast resistant material disposed below the additional layer of blast resistant material.

36. The sole of claim 35, wherein the still further layer comprises at least one layer of woven aramid and at least one layer of woven ceramic fibre.

37. The sole of claim 35 or claim 36, wherein the still further layer comprises a plurality of alternating layers of woven aramid and woven ceramic fibre.

38. The sole according to any one of claims 35 to 37, wherein the woven ceramic fibre layer is the bottommost layer of the still further layer of blast resistant material.

39. The sole according to any one of claims 35 to 38, wherein the further layer include two layers of woven aramid fibre alternately layered with two layers of woven ceramic fibre, and further wherein one of the woven ceramic layers is the bottommost layer of the still further layer.

40. The sole according to any one of claims 1 to 39, wherein the sole includes a bottommost ground-engaging layer.

41. The sole of claim 40, wherein the ground-engaging layer is formed from rubber or polyurethane.

42. The sole of claim 40 or claim 41, wherein the ground-engaging layer is formed in two layers, an outermost layer and an inner layer.

43. The sole of claim 42, wherein the outermost layer is a nitrile rubber and the inner layer is a foam rubber.

44. An article of footwear including a sole according to any one of claims 1 to 43.

45. The article of footwear of claim 44, wherein the article includes a cocoon of substantially blast resistant material that is incorporated into the footwear, the cocoon having a sole and an upper such that the cocoon would substantially or entirely surround the foot of a wearer of the article of footwear.

46. The article of footwear of claim 45, wherein the upper is formed from an outer layer and an inner layer between which the cocoon is positioned.

47. The article of footwear of claim 45 or claim 46, wherein the cocoon includes at least two layers of woven aramid fibre.

48. The article of footwear according to any one of claims 45 to 47, wherein the cocoon comprises a sandwich of layers of woven ceramic fibres or woven ceramic/glass-ceramic composite fibres and aramid fibres.

49. The article of footwear according to any one of claims 45 to 48, wherein the sole is stitched about its periphery to the cocoon.