Immersion protection garments

Abstract

An immersion protection garment (10) has at least one sheet of flexible material that includes graphene. The sheet of material further may include a polyurethane, PU, or thermoplastic polyurethane, TPU. A first and second sheet of flexible material that includes graphene may comprise respective panels 30, 32 of the garment that are joined together at a seam (28).

Description

IMMERSION PROTECTION GARMENTSTECHNICAL FIELD

[0001] The present invention relates to immersion protection garments .BACKGROUND TO THE INVENTION

[0002] Immersion protection garments ( IPGs ) , including apparel that comprises a garment that provides a barrier to protect a wearer from the effects of being immersed in water or acts as a barrier surrounding the body to protect against liquids are known.

[0003] IPGs are worn to protect a person in a number of scenarios and uses, such as where immersion in water could lead to the danger of hypothermia where the loss of heat to the surroundings is far greater when immersed than when dry. For example IPGs may include :• Suits worn for transport or working over water (e . g .Helicopter Transfer Suits , survival suits on offshore platforms etc . ) , crews on patrol and rescue craft, and aircrew flying aircraft over water . Such suits are worn as a precaution against the dangers from immersion .• Suits worn by those in diving operations and working underwater .• Suits worn by those who may be exposed to toxic agents such as chemical, biological and nuclear agents .

[0004] A barrier layer of the garment can consist of a number of alternatives including woven textiles such as nylon, polyester, cotton, Nomex® etc . as well as films such thermoplastic polyurethane (TPU) , etc . , and also a combination of these . Such garments have a number of shortcomings , and these include :They are not inherently flame and fireproof• They are too heavy and stiff when worn• They are not "breathable" and place an unacceptable thermal burden on the wearer .• They are not robust enough to withstand repeated wear and laundering etc .• They produce a thermal image on thermal and IR location cameras and equipment• They cannot be used as electro conductive elements• They lack elasticity making them difficult to don and doff .SUMMARY OF THE INVENTION

[0005] According to one aspect of the invention, there is provided an immersion protection garment ( IPG) having at least one sheet of flexible material that includes graphene .

[0006] The IPG may be a dry suit, a submarine escape suit or the like .

[0007] IPGs that incorporate graphene may have various benefits . The suits may be inherently fireproof and flame proof, and may be manufactured and at a lower cost than known suits using more expensive fire retardant ( FR) materials .

[0008] IPGs made using graphene materials may be lighter than and not as stiff as known suits, making them more comfortable and less obstructive to wear . Suits made using graphene materials may also be more elastic making them easier to don and doff .

[0009] IPGs that incorporate graphene may have greater breathability and more effective heat transmission properties placing less thermal burden on the wearer .

[0010] Testing has shown that IPGs that incorporate graphene may have a much lesser image when viewed on a thermal or infrared ( IR) imager, which may be important when used in a military engagement .

[0011] Graphene materials can be electro conductive which allows the integration of electrical equipment into the IPG .

[0012] Graphene materials may have greater biocompatibility with the wearer making IPGs incorporating graphene less likely to cause skin irritation, etc .

[0013] Graphene can be defined as a lattice of hexagonal carbon atoms having a single layer of atoms arranged in a honeycomb planar nanostructure . Graphene Nano Platelets (GNPs ) can be defined as platelet-shaped sheets of graphene stacked on top of one another . These graphitic stacks may have an average thickness of 1-2 nanometres . GNPs may possess many of the same properties as graphene . The graphene in the at least one sheet of flexible material, according to various embodiments of the invention, may be in the form of GNPs or other forms of graphene, including pure graphene .

[0014] The sheet of material may also include polyurethane, PU, and / or thermoplastic polyurethane, TPU . Graphene may be dispersed into PU / TPU at the melt stage in the form of GNPs .

[0015] The sheet of material may be formed from fibres , threads or yarn that contains graphene . The fibres, threads or yarn may be woven together to form the sheet of material . The fibres, threads or yarn may also include polyurethane, PU, and / or thermoplastic polyurethane, TPU . Graphene may be dispersed into PU / TPU at the melt stage in the form of GNPs .

[0016] Embodiments of the invention may provide IPGs using flexible polymer films (e . g . PU or TPU) incorporating graphene to create waterproof and / or air holding materials . Such incorporation of graphene into the PU / TPU film may increase its strength and contributes to the overall performance of the equipment .

[0017] Embodiments of the invention may provide IPGs usingone of more sheets of material, e . g . including PU or TPU, and incorporating graphene . Such incorporation of graphene into the sheet of material may increase its strength and flame retardance, and contributes to the overall performance of the equipment .

[0018] The sheet of material may be fluid impermeable . This allows the sheet of material, inter alia, to form a pressure holding inflatable item. Pressure holding inflatable items are normally referred to as "bladders" . Inflatable bladders can be inflated orally by mouth or from a compressed gas source such as a cylinder of compressed COp .

[0019] A flexible polymer, typically for example PU or TPU, film incorporating graphene may also be used to create a flexible material which is waterproof and can be used to manufacture IPGs which can be sealed against water ingress .

[0020] The sheet of material may have a thickness of between 100 and 150pm.

[0021] The sheet of material may include between 1 and 10% graphene (by weight ) , preferably 1.5% graphene by weight . Samples of a number of different percentages of graphene by weight ranging from 1% to 5% were tested in four ways - being breaking force, puncture resistance, weld strength and tear strength. The most effective percentage of GNPs within the TPU was found to be 1.5% .

[0022] The sheet of material may be moisture-vapour permeable . This may improve comfort of a garment and allow the passage of perspiration through the material .

[0023] The sheet of material may be flame retardant (e . g . it will be less damaged by fire than a non-graphene including sheet of material) .

[0024] The immersion protection garment may include first and second sheets of material, one of which is said at least onesheet of flexible material that includes graphene . The first and / or second sheet of flexible material may include graphene

[0025] The first sheet of material may be arranged to support the second sheet of flexible material . So arranged, the first and second sheets may for a layered structure .

[0026] The second sheet of flexible material may be bonded to the first sheet of material . So arranged, the first and second sheets may for a layered structure .

[0027] The second sheet material may be separate from the first sheet of material .

[0028] The first and second sheet of flexible material may comprise respective panels of the garment that are joined together . So arranged, the first and second sheets may lie generally side-by-side . The garment may comprise a multiplicity of such panels that are joined together by seams between the panels .

[0029] An edge region of the first sheet of sheet of flexible material may be overlapped with an edge region of the second sheet of flexible material and the edge regions may be welded together . This may provide a watertight seam between the panels that stops water penetrating the garment .

[0030] An edge region of the first sheet of sheet of flexible material and an edge region of the second sheet of flexible material may be oriented so that they extend generally parallel to each other and are welded together . The edges may be bent at approximately right angles to a main portion of the sheets . This may provide a watertight seam between the panels that stops water penetrating the garment .

[0031] The parts of the first sheet of sheet of flexible material and parts of the second sheet of flexible material that are welded together may comprise TPU or PU. TPU or PU may include graphene . These sheets may be waterproof . The sheets may furthercomprise fibres, threads or yarn are that are woven together, and may include graphene .

[0032] An edge region of the first sheet of sheet of flexible material may be overlapped with an edge region of the second sheet of flexible material and the edge regions may be stitched together . The edge region of the first sheet of sheet of flexible material and / or the edge region of the second sheet of flexible material may be folded over itself to form a hem prior to stitching the edge regions together .

[0033] The first sheet of sheet of flexible material and / or the second sheet of flexible material may comprise fibres , threads or yarn that are woven together to form the sheet of material, and wherein a layer of material is laminated onto the first sheet of sheet of flexible material and the second sheet of flexible material and the j oin therebetween that is stitched together . The layer of material is laminated onto the first sheet of sheet of flexible material and the second sheet of flexible material may render the j oin waterproof .

[0034] The first sheet of sheet of flexible material and / or the second sheet of flexible material may comprise fibres , threads or yarn that are woven together to form one layer of the sheet of material, which one layer is bonded to a second layer comprising TPU or PU, and wherein a piece of material (e . g . tape) may fixed onto the first sheet of flexible material and the second sheet of flexible material in a region of the join therebetween . The piece of material fixed onto the first sheet of flexible material and the second sheet of flexible material may render the join waterproof .

[0035] The immersion protection garment of may include an inflatable chamber that functions as a lifejacket or life preserver unit, LPU. The inflatable chamber may be located under an outer garment layer of the garment when deflated, wherein the outer garment layer includes a line of weakness that opens due to pressure applied by partial inflation of the inflatable chamber to allow full inflation of the inflatable chamberoutside the outer garment layer of the garment . The inflatable chamber may be located between the outer garment layer and an inner garment layer of the garment when deflated . The sheet of flexible material that includes graphene forms the outer garment layer and / or the inner garment layer .

[0036] The IPG may have at least one further non-graphene sheet of material ( i . e . a sheet of material that does not contain graphene ) . The non-graphene sheet of material may support the sheet of flexible material that includes graphene . The sheet of flexible material that includes graphene may have a lower modulus of elasticity the non-graphene sheet of material . The non-graphene supporting sheet of material may limit the expansion or stretching of the sheet of flexible material that includes graphene (e . g . as a bladder incorporating the sheet of flexible material that includes graphene ) . The non-graphene supporting sheet of material may protect the sheet of flexible material that includes graphene from abrasion or other damage . Alternatively, the supporting sheet of material may include graphene, and the sheet of material supported by the supporting sheet of material may or may not include graphene .

[0037] IPGs comprising conventional films or sheets of material (without graphene reinforcement) have a number of disadvantageous features; these include limited tensile strength, limited resistance to impact damage, low modulus (modulus of elasticity) , low thermal stability and poor flame retardancy. Studies have shown that by incorporating graphene into a sheet or film (e . g . a PU / TPU film) it is possible to improve a number of characteristics of the sheet or film to the overall advantage of the equipment' s performance . For example see : "Chemical Engineering Journal" Vol 482 15thFebruary 2024 "The Reinforcement of Polyurethane by Mini-Sized Graphene with Superior Performances" . Such laboratory studies have indicated that the inclusion of graphene in PU material can provide the following benefits to the PU film and therefore to the equipment :Improved tensile strength by up to 80%Modulus by up to 126%Increased mechanical performanceIncreased shape memoryThe PU film can be fire retardant and generate limited smoke

[0038] Bladders (inflatable chambers ) incorporating graphene (and e . g . PU / TPU) , according to embodiments of the invention have been manufactured and tested and found to have the following improvements over the same non-Graphene bladders :Average breaking force increased by 40%Average puncture resistance improved by 10%Average weld strength improved by 39%Average tear strength improved by 10%

[0039] Reducing the weight of the product is very advantageous for IPGs . The thickness and therefore the weight of the PU film can be reduced while still achieving the same or better strength characteristics of the non-graphene PU film.

[0040] Additionally reducing the thickness of a grapheneincluding PU / TPU sheet or film may make it more flexible and therefore easier to pack into a more compact space thereby further saving space and weight .BRIEF DESCRIPTION OF THE DRAWINGS

[0041] For a better understanding of the present invention embodiments will now be described by way of example, with reference to the accompanying drawings , in which :Fig . 1 is a front view of an immersion protection garment ( IPG) ;Figs . 2 to 7 are partial views showing different forms of pieces of material that may be used to form an immersion protection garment;Figs . 8 , 9, 10 and 11 are partial views showing how two pieces of material may be joined and may be sealed at their seams in various different ways ;Fig . 12 is a front view of another IPG;Fig . 13 shows a front view of a further IPG;Fig . 14 shows a left side view of the protective flight garment of Fig . 13 (other side corresponds ) ;Fig . 15 shows a rear elevational view of the protective flight garment of Fig . 13 ;Fig . 16 shows a cross-section taken along line A-A of Fig . 13 and 14 , including a partially enlarged view, as indicated by the arrow "A";Fig . 17 shows a front elevational view of the protective flight garment of Fig . 13 after its inflatable chamber is inflated;Fig . 18 shows a left side view of the protective flight garment of Fig . 13 after its inflatable chamber is inflated is inflated (other side corresponds ) ;Fig . 19 shows a cross-section taken along line A-A of Figs . 17 and 18 ;Fig . 20A shows a cross-sectional view of an inflatable chamber;Fig . 20B shows an enlarged detailed view of the layers of the inflatable chamber of Fig . 20A; andFig . 20C shows an enlarged view of the inflatable chamber of Fig . 20A where the upper and lower layers are connected .

[0042] In the drawings , like elements are generally designated with the same reference signs .DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0043] An immersion protection garment ( IPG) according to various embodiments has at least one sheet of flexible material that includes graphene . The sheet of flexible material may also include a flexible polymer - such as polyurethane, PU, and / or thermoplastic polyurethane, TPU.

[0044] The sheet of flexible material may be formed by dispersing graphene in the form of Graphene Nano Platelets(GNPs ) into PU / TPU at the melt stage . The sheet of material may have a thickness of between 100 and 150pm. The sheet of material may include between 1 and 10% graphene by weight, preferably 1.5% graphene by weight .

[0045] The sheet of material may be formed from fibres , threads or yarn that contains graphene . The fibres, threads or yarn may be woven together to form the sheet of material . The fibres, threads or yarn may also include polyurethane, PU, and / or thermoplastic polyurethane, TPU . Graphene may be dispersed into PU / TPU at the melt stage in the form of GNPs to from the fibres , threads or yarn .

[0046] Embodiments of the invention may provide immersion protection garments using flexible polymer films (e . g . PU or TPU) incorporating graphene to create waterproof and / or airholding materials . Such incorporation of graphene into the PU / TPU film may increase its strength and flame retardancy, and may contribute to the overall performance of the equipment .

[0047] The graphene-including sheet of material may be fluid impermeable . This allows the sheet of material to form a pressure-holding inflatable item and / or to form a waterproof garment / item.

[0048] Embodiments of the invention may provide IPGs using one or more sheets of material . The sheet of material may be formed from fibres , threads or yarn that contains graphene . The fibres, threads or yarn may be woven together to form the sheet of material . The fibres , threads or yarn may include PU or TPU, and incorporate graphene . Such incorporation of graphene into the fibres, threads or yarn of the sheet of material may increase the strength of the sheet and flame retardancy, and contributes to the overall performance of the equipment .

[0049] A graphene-including flexible sheet of material may be incorporated into an IPG in a number of ways .

[0050] An example IPG is shown in Fig . 1. The IPG may be a suit 10 that includes a barrier material . The barrier material of the suit 10 can completely or partially cover the body of the wearer .

[0051] The suit 10 may be fitted with a wrist seal 12 made of a flexible and elastic material such that it forms a seal around the wrist . A similar ankle seal 14 may also be used around the ankle . In Fig . 1 a wrist seal 12 and ankle seal 14 are shown for the right-hand side of the suit 10 , although in practice a wrist seal 12 and ankle seal 14 would also be provided on the left-hand side of the suit 10. The wrist seal 12 and / or ankle seal 14 may be made using graphene reinforced or graphenecontaining materials .

[0052] Alternatively, a waterproof glove 16 and / or waterproof sock 18 may be fitted to the suit 10. The waterproof glove 16 and / or waterproof sock 18 may be integral with the main body of the suit 10 or may be attached to the suit 10 by a fluid-tight connection (e . g . by welding or adhesive ) . In Fig . 1 a waterproof glove 16 and waterproof sock 18 are shown for the left-hand side of the suit 10 , although in practice a waterproof glove 16 and waterproof sock 18 would also be provided on the right-hand side of the suit 10. The waterproof glove 16 and / or waterproof sock 18 may be made using graphene reinforced or graphene-containing materials .

[0053] A neck seal 20 may be fitted to the suit to prevent water ingress or a waterproof head covering, shown partially at 22 , forming a seal around the face may be fitted as an alternative . The neck seal 20 and / or head covering 22 may be made using graphene reinforced or graphene-containing materials .

[0054] Typically, a waterproof zipper 24 may be fitted to the suit 10 to allow wearer access into the suit 10. The waterproof zipper 24 may be made using graphene reinforced or graphene-containing materials . The waterproof zipper 24 may be attached to the main body of the suit 10 using graphene reinforced or graphene-containing materials .

[0055] The suit 10 may also be fitted with one way valves (vents ) 26 to allow excess air (or other gas ) to escape from the suit 10.

[0056] The suit 10 may also be fitted with an integrated life preserver unit (LPU) 29. Such an arrangement is described below in relation to Figs . 13 to 20C .

[0057] The suit 10 may be made by cutting out separate panels and j oining them together by creating waterproof seams . For example, there may be a seam 28 between a panel 30 forming an arm portion and a panel 32 forming a torso portion of the suit 10 of Fig . 1. The suit 10 may comprise multiple panels that are joined together by seams 28. The panel 30 forming an arm portion and a panel 32 forming the torso portion is merely one example .

[0058] Figs . 2 to 7 show different ways in which a grapheneincluding flexible sheet of material may be incorporated into one or more panels of the suit 10. Figs . 2 to 7 are partial cross-sectional views at any point through the suit 10. The respective panels of the suit 10 may have different layers . Panels with different layer types may be j oined by seams 28 .

[0059] In Fig . 2 a piece of flexible material 40 may be formed by a graphene-including inner flexible sheet of material 42 (e . g . including PU or TPU) that is coated or laminated onto an inner face 44 of a supporting substrate 46 such as a woven textile (e . g . coated or laminated onto the entire inner face 44 of the supporting substrate 46 ) . The flexible sheet of material 42 creates a fluid barrier . The outer textile supporting substrate 46 provides strength, abrasion resistance and may limit the elasticity of the suit 10 to create a dimensionally stable structure . The inner flexible sheet of material 42 faces the wearer' s skin . The supporting substrate 46 may be a nongraphene sheet of material ( i . e . a sheet of material that does not contain graphene) .

[0060] The supporting substrate 46 of Fig . 2 may be a graphene-containing sheet of material . The supporting substrate 46 may be formed by weaving together fibres , threads or yarn that contain graphene . In an arrangement where the supporting substrate 46 of Fig . 2 is a graphene-containing sheet of material, the flexible sheet of material 42 may be formed by a graphene-including flexible sheet or may be formed by a non-graphene sheet ( i . e . a sheet of material that does not contain graphene) .

[0061] In Fig . 3 the piece of flexible material 40 may be formed by a graphene-including outer flexible sheet of material 42 that is coated or laminated onto an outer face 48 of an inner supporting substrate 46A, such as a woven textile (e . g . coated or laminated onto the entire outer face 48 of the inner supporting substrate 46A) . The flexible sheet of material 42 creates a fluid barrier . The inner supporting substrate 46A provides strength and may limit the elasticity of the suit 10 to create a dimensionally stable structure . The inner supporting substrate 46A may be a non-graphene sheet of material (i . e . a sheet of material that does not contain graphene) . The flexible sheet of material 42 may protect the inner supporting substrate 46A from damage . The flexible sheet of material 42 may provide an outer surface onto which other items formed of PU / TPU may be readily attached - e . g . by high-frequency welding . The inner supporting substrate 46A faces the wearer' s skin .

[0062] The inner supporting substrate 46A of Fig . 3 may be a graphene-containing sheet of material . The inner supporting substrate 46A may be formed by weaving together fibres, threads or yarn that contain graphene . In an arrangement where the inner supporting substrate 46A of Fig . 3 is a graphene-containing sheet of material, the flexible sheet of material 42 may be formed by a graphene-including flexible sheet (e . g . including PU or TPU) or may be formed by a non-graphene sheet (i . e . a sheet of material that does not contain graphene) .

[0063] In Fig . 4 the piece of flexible material 40 may be formed by a graphene-including flexible sheet of material 42 (e . g . including PU or TPU) that is coated or laminated onto an inner face 24 of an outer supporting substrate 46B ( such as a woven textile) and coated or laminated onto an outer face 48 of an inner supporting substrate 46A ( such as a woven textile) . For example, the flexible sheet of material 42 is coated or laminated onto the entire inner face 44 of an outer supporting substrate 46B and coated or laminated onto the entire outer face 48 of an inner supporting substrate 46A. The flexible sheet of material 42 is sandwiched between an inner and outer supporting substrates 46A, 46B . The flexible sheet of material 42 creates a fluid barrier . The inner supporting substrate 46A faces the wearer' s skin . The inner supporting substrate 46A provides strength and may limit the elasticity of the suit 10 to create a dimensionally stable structure . The outer supporting substrate 46B provides strength, abrasion resistance and may limit the elasticity of the suit 10 to create a dimensionally stable structure . The inner supporting substrate 46A and / or the outer supporting substrate 46B may be a non-graphene sheet of material ( i . e . a sheet of material that does not contain graphene) .

[0064] The inner supporting substrate 46A of Fig . 4 may be a graphene-containing sheet of material . The inner supporting substrate 46A may be formed by weaving together fibres, threads or yarn that contain graphene . Alternatively, or additionally, outer supporting substrate 46B of Fig . 4 may be a graphenecontaining sheet of material . The outer supporting substrate 46B may be formed by weaving together fibres , threads or yarn that contain graphene . In an arrangement where the inner supporting substrate 46A and / or the outer supporting substrate 46B of Fig .4 is a graphene-containing sheet of material, the flexible sheet of material 42 may be formed by a graphene-including flexible sheet or may be formed by a non-graphene sheet (i . e . a sheet of material that does not contain graphene) .

[0065] In Fig . 5 the piece of flexible material 40 (e . g . including PU or TPU) may be formed by an inner graphene-including flexible sheet of material 42 and an outer sheet 50 such as a woven textile (similar to the supporting substrate 46 of Fig .2 ) . However, in this embodiment, the flexible sheet of material 42 is not attached to outer sheet 50 but is unsupported, or may be selectively attached to the outer sheet 50. The flexible sheet of material 42 may be within but completely separate from the outer sheet 50. The flexible sheet of material 42 may be connected to the outer sheet 50 at one or more points which form a minority of the surface area of the outer sheet 50. The outer sheet 50 may be a non-graphene sheet of material ( i . e . a sheet of material that does not contain graphene ) . The outer sheet 50 faces the wearer' s skin .

[0066] The outer sheet 50 of Fig . 5 may be a graphenecontaining sheet of material . The outer sheet 50 may be formed by weaving together fibres, threads or yarn that contain graphene . In an arrangement where the outer sheet 50 of Fig . 5 is a graphene-containing sheet of material, the flexible sheet of material 42 may be formed by a graphene-including flexible sheet or may be formed by a non-graphene sheet (i . e . a sheet of material that does not contain graphene) .

[0067] In Fig . 6 the piece of flexible material 40 is formed by a graphene-including flexible sheet of material 42 (e . g . including PU or TPU) . In this embodiment graphene-including flexible sheet of material 42 is not supported in any way and forms a single layer of the suit 10. The graphene-including flexible sheet of material 42 may provide an outer surface onto which other items formed of PU / TPU may be readily attached -e . g . by high-frequency welding .

[0068] In Fig . 7 the piece of flexible material 40 may be formed by two graphene-including flexible sheets of material 42A and 42B (e . g . including PU or TPU) . Inner flexible sheet of material 42A is coated or laminated onto an inner face 44 (e . g . onto the entire inner face 44 ) of a supporting substrate 46(such as a woven textile) . Outer flexible sheet of material 42B is coated or laminated onto an outer face 48 (e . g . onto the entire outer face 48 ) of the supporting substrate 46. The supporting substrate 46 is "sandwiched" between the inner and outer flexible sheets of material 42A and 42B . The flexible sheets of material 42A and 42B create a fluid barrier . The supporting substrate 46 provides strength and may limit the elasticity of the suit 10 to create a dimensionally stable structure . The flexible sheets of material 42A and 42B provide redundancy, so that the fluid-tight nature of the suit may be maintained when one of the flexible sheets of material 42A and 42B is damaged. The supporting substrate 46 may be a non-graphene sheet of material ( i . e . a sheet of material that does not contain graphene) . The outer flexible sheet of material 42B may protect the supporting substrate 46 from damage . The outer flexible sheet of material 42B may provide an outer surface onto which other items formed of PU / TPU may be readily attached - e . g . by high-frequency welding . The outer flexible sheet of material 42B faces the wearer' s skin .

[0069] The supporting substrate 46 of Fig . 7 may be a graphene-containing sheet of material . The supporting substrate 46 may be formed by weaving together fibres , threads or yarn that contain graphene . In an arrangement where the supporting substrate 46 of Fig . 7 is a graphene-containing sheet of material, the flexible sheets of material 42A and 42B may be formed by a graphene-including flexible sheet or may be formed by a non-graphene sheet (i . e . a sheet of material that does not contain graphene) .

[0070] Although in the arrangements described above, the piece of flexible material 40, forming part of the suit 10 , may be formed by a graphene-including flexible sheet of material, it should be understood that the suit 10 will comprise a plurality of pieces of material (panels ) . All of these pieces of material may be formed by a graphene-including flexible sheet of material of the type described in any one of Figs . 2 to 7 ,or only some of the pieces of flexible material 40 may formed by a graphene-including flexible sheet of material (the other piece of flexible material may be fluid-tight but not include graphene ) . A piece of material like the flexible material 40 may form the panel 30 forming the arm portion and may form the panel 32 forming the torso portion of the suit 10 of Fig . 1

[0071] The graphene-including flexible sheet of material 42 can be made MVP (Moisture Vapour Permeable ) , termed "breathable", if required . For example, the graphene-including flexible sheet of material 42 may have a molecular structure that allows moisture vapour to pass through but that does not allow water to pass through .

[0072] Typically, such suits 10 are formed from a plurality of pieces of flexible material (panels ) , such as the pieces of material of the suit 10 described above . The pieces of material may include (or consist of ) graphene-including flexible sheets of material, such as the graphene-including flexible sheet of material 42 and / or flexible sheet of woven material 46, 46A, 46B of the IPG above . Edges of one or more pieces of material may be connected together to form an IPG .

[0073] Pieces of material may be sealed at their seams in various ways . Pieces of material may be sealed at their seams by being glued or welded (e . g . welded together by high frequency welding) . The seams can be "in shear", peel or peel and shear, .

[0074] As mentioned above, the suit 10 may be made by cutting out separate panels and j oining them together by creating waterproof seams - for example using one of the techniques shown in Fig . 8 , 9, 10 or 11. For example, there may be a seam 28 between the panel 30 forming an arm portion and the panel 32 forming a torso portion of the suit 10 of Fig . 1. The panels 30 , 32 and the seam 28 may also be located at other parts of the suit 10.

[0075] The first panel 30 may be formed as described above in relation to Fig . 2. - with a graphene-including inner flexible sheet of material 42 , such as TPU containing graphene, that is coated or laminated onto an inner face 44 of a graphenecontaining supporting substrate 46, such as a woven textile containing graphene . The inner flexible sheet of material 42 faces the wearer' s skin . The first panel 30 may, however, be formed as described in relation to any one of Figs . 2 to 7 .

[0076] The second textile panel 32 may be formed as described above in relation to Fig . 2. - with a graphene-including inner flexible sheet of material 42 , such as TPU containing graphene, that is coated or laminated onto an inner face 44 of a graphenecontaining supporting substrate 46, such as a woven textile containing graphene . The inner flexible sheet of material 42 faces the wearer' s skin . The second textile panel 32 may, however, be formed as described in relation to any one of Figs .2 to 7 . The first panel 30 and the second panel 32 may be formed differently from each other .

[0077] In Fig . 8 , the first panel 30 and the second panel 32 are stitched together and a waterproof tape 50 is applied to cover the internal side 51 ( facing the wearer' s body in use ) of the seam 28. This can be done in a single operation or by stitching first and then taping . The first panel 30 in this example is formed as described in relation to Fig . 2. The second panel 32 in this example is formed as described in relation to Fig . 2 .

[0078] An edge 56 of first panel 30 may be folded back under itself to form a hem 52. An edge 58 of the second panel 32 is arranged to overlap the underside of the hem 52. The second panel 32 may optionally also be provided with a hem at the edge 58. The hem 52 of panel 30 and the overlapping edge 58 of the second panel 32 are then stitched together by tread 57. The tape 50, for example, comprising TPU, is applied to the internal side 51 of the seam 28 to cover a region where the edge 58 of the second panel 32 overlaps the underside of the hem 52 and toextend either side of that region . The tape 50 is attached at 53 to the internal side of the first panel 30 that is adjected to the hem 52. The tape 50 is attached at 54 to the internal side of the second panel 32 adjacent to the edge 58 of the second panel 32 that overlaps the underside of the hem 52 . Between the attachment points 53, 54 , the tape 50 covers the seam 28 on the interior side 51 of the suit 10. The tape 50 may be attached to at 53 to the internal side of the first panel 30 by welding or gluing (or otherwise fixing together) . The tape 50 may attached at 54 to the internal side of the second panel 32 by welding or gluing (or otherwise fixing together) . The tape 50 may be waterproof and / or fluid impermeable . When the attachment points 53 , 54 are also waterproof and / or fluid impermeable, this prevents water / fluid entering the internal side 51 of the suit 10 through the seam 28 .

[0079] In Fig . 9 opposite faces of the first panel 30 and the second panel 32 are welded together . The first panel 30 in this example is formed as described in relation to Fig . 2 . The second panel 32 in this example is formed as described in relation to Fig . 2. The first panel 30 and the second panel 32 are arranged lying in generally the same plane, and adjacent edges 56, 58 are brought together, with edges 56, 58 then bent through 90° so that the edges 56, 58 abut and extend generally perpendicularly in a direction away from the internal side 51 of the suit 10. The seam 28 is formed by welding or gluing (or otherwise fixing together) the edge 56 of the first panel 30 and the edge 58 of the second panel 32. The weld (or adhesive ) between the edges 56, 58 is designated 60. Such seams 28 as shown in Fig . 9 can be referred to as "in peel" . When the weld 60 is waterproof and / or fluid impermeable, this prevents water / fluid entering the internal side 51 of the suit 10 through the seam 28 .

[0080] In Fig . 10 opposing faces of the first panel 30 and the second panel 32 are lap welded together to form the seam 28 .Such seams 28 as shown in Fig . 10 can be referred to as "in shear" .

[0081] In Fig . 10 the first panel 30 and the second panel 32 may be formed as described in relation to Fig . 7. For each panel 30, 32 an inner flexible sheet of material 42A, such as TPU containing graphene, is coated or laminated onto an inner face 44 of a supporting substrate 46 (such as a woven textile ) . Outer flexible sheet of material 42B, such as TPU containing graphene, is coated or laminated onto an outer face 48 of the supporting substrate 46. The supporting substrate 46 is "sandwiched" between the inner and outer flexible sheets of material 42A and 42B .

[0082] The edge 56 of outer flexible sheet of material 42B of the second panel 32 may provide a surface onto which the edge 58 of the inner flexile sheet of material 42A of the first panel 30 may be readily attached - e . g . by welding (or otherwise attaching) at 60. The inner flexile sheets of material 42A faces the wearer' s skin . When the weld 60 is waterproof and / or fluid impermeable, this prevents water / fluid entering the internal side 51 of the suit 10 through the seam 28 .

[0083] The supporting substrate 46 of Fig . 10 may be a graphene-containing sheet of material . The supporting substrate 46 may be formed by weaving together fibres , threads or yarn that contain graphene .

[0084] In Fig . 11 , the suit 10 may be made by stitching together by tread 57 the first panel 30 and the second panel 32 and then waterproofing by applying a waterproof layer to the suit 10 or moulding the suit 10 into its shape .

[0085] The first panel 30 and the second panel 32 may each be a sheet of textile material formed by weaving together fibres , threads or yarn that contain graphene . The edge 56 of the first panel 30 is overlapped with the edge 58 of the second panel 32 at the seam 28. A flexible sheet of material 70, such as TPUcontaining graphene, is coated or laminated onto the panels 30 , 32 on the internal side 51 of the suit 10 and covers the seam 28 , forming an inner layer of the suit 10. The flexible sheet of material 70 may be waterproof and / or fluid impermeable, this prevents water / fluid entering the internal side 51 of the suit 10 through the panels 30 , 31 and seam 28.

[0086] Examples of a suit where graphene may be used are for example described in WG2008 / 035036 ( SEIE 40365 ) .

[0087] As mentioned above, IPGs are worn when there is the possibility of the wearer deliberately or accidentally entering the water . The IPG (or Survival Suit ) provides an effective barrier against the water and is typically fitted with a waterproof zipper, neck and wrist seals or other methods of preventing water entering the suit . Keeping the wearer dry is vital in preventing hypothermia and drowning .

[0088] Fig . 12 shows another example of an IPG, a submarine escape suit 10. The submarine escape suit comprises panels like the first panel 30 and the second panel 32 described above, and j oined together in one or more of the ways described above . Some or all of the panels in some cases may be moisture-vapour permeable (MVP) to provide greater comfort to the wearer and reduce thermal burden .

[0089] The suit 10 is formed with a body portion 110, left leg and right leg portions Illa, 111b and left and right arm portions 112a, 112b . In addition, the suit includes a hood 113 provided with translucent panels 114. The hood 113 would conventionally also be made of the same material with TPU as the suit itself .

[0090] A central zip 115 allows access to the suit and releasable side connections 116a, 116b that allow a central face panel 117 to be lifted away from the face of a wearer . The suit is completed by foot coverings in the form of left and right boots 126a, 126b .

[0091] Any of the body portion 110, left leg and right leg portions Illa, 111b, and left and right arm portions 112a, 112b, hood 113, translucent panels 114 , releasable side connections 116a, 116b, central face panel 117 , and foot coverings in the form of left and right boots 126a, 126b may comprise one or panels having a form described above in relation to any one of Figs . 2 to 7 , and these panels may be joined by any of the methods described above in relation to any one of Figs . 8 to 11.

[0092] The suit may also include a liferaft shown in broken line at 131. The liferaft is for use by a wearer on reaching the sea surface, when the liferaft is inflated and deployed before being boarded by the wearer . Such liferafts are known from, for example, EP-A-0444400 .

[0093] The suit also includes a strap 121 is formed from a band of inflexible material . The strap 121 extends from a first point on the back of the body portion towards an upper end of the back portion through the crotch region between the left and right legs to a second point 133 on the front of the body portion towards the lower end of the hood 113. This strap 121 includes an adjustment buckle 134 .

[0094] Such suits may be subj ected to heavy wear and use particularly if they are within a working environment and can be subj ected to damage and excessive wear which will damage a conventional TPU layer leading to leakage and failure of the suit to protect the wearer . The suits may also be laundered frequently leading to deterioration of the conventional TPU layer .

[0095] The suit preferably complies with a number of requirements to meet Regulations as well as user demands including durability, ability to withstand the high pressures as a consequence of escaping at depth from the submarine, to not be affected by a range of possible contaminants within the submarine including engine fumes, resistance to flame and fire, able to withstand a range of temperatures , resistant to damageduring the escape and on the surface, requirement not to create too great a thermal burden on the wearer . The suit is very tightly packed within a valise to save space and must be able to withstand compression and also must be as light as possible to be accommodated within the submarines weight allowances .

[0096] The suit 10 is unpacked and donned within the submarine in an emergency prior to the escape from the submerged submarine . The suit 10 is packed in a valise and stored in a submarine for emergency use . In use, the suit 10 is taken from the valise and the zip 115 undone . The wearer then climbs into the suit 10 through the aperture formed by the open zip 115 inserting arms and legs into the arm and leg portions Illa, 1 11b, 112a, 112b as appropriate . The wearer ' s feet enter the left and right boots 126a, 126b (if provided) and the suit 10 is arranged around the shoulders of the wearer . The wearer then enters an escape chamber and connects to the air supply system of the submarine . This passes air into the suit 10 and more particularly into the hood 113. When the escape chamber has been filled with water, a hatch opens and a wearer exits the escape chamber . The wearer then rises to the surface breathing air within the hood 113. At the surface, the wearer floats on his / her back and the liferaft 131 ( if provided) can be deployed, inflated and boarded.

[0097] According to this embodiment of the invention, the suit 10 and / or hood 113 include at least one sheet of flexible material that includes graphene, of the type / composition as discussed above . The sheet of flexible material may also include a flexible polymer such as PU and / or TPU, as discussed above . The sheet of flexible material that includes graphene may be a woven sheet formed of graphene-including fibres , threads or yarn . The sheet of flexible material that includes graphene may provide improved performance and resistance to wear and damage .

[0098] According to another embodiment of the invention, the immersion protection garment carries a buoyancy-providinginflatable bladder and no separate lifejacket is required . That is, the inflatable bladder is integrated into the immersion protection garment that is worn on the body of the wearer .

[0099] Referring first to Figures 13 , 14 and 15 , a novel immersion protection garment 210 that in this example is a vest (but could instead be a jacket or full body suit) is provided . The immersion protection garment 210 comprises panels like the first panel 30 and the second panel 32 described above in relation to any one of Figs . 2 to 7 , and joined together by seams 28 in one or more of the ways described above as described in relation to any one of Figs . 8 to 11.

[0100] The immersion protection garment 210 may include special equipment (Aircrew Life Support Equipment - ALSE ) that protects the wearer against the effects of high G-acceleration or altitude and other potentially damaging factors .

[0101] The immersion protection garment 210 has a waist portion 212 , a neck opening 214 , and left and right arm holes 216A and 216B, respectively. The immersion protection garment 210 also has a front opening 218 closed by, for example, a conventional zipper . When the front opening 218 is closed, the immersion protection garment 210 is securely attached to the body of the wearer .

[0102] The immersion protection garment 210 carries equipment pockets 220. The immersion protection garment 210 also carries a waist belt 222 . The waist belt 222 may be secured at the front of the torso by a buckle 223 or any other suitable coupling . The waist belt 222 may include graphene . The buckle 223 may include graphene .

[0103] The immersion protection garment 210 in the embodiment extends at least over the aircrew member' s chest and back, and behind their neck, and may comprise one or panels having a form described above in relation to any one of Figs . 2 to 7 , and these panels may be joined by any of the methodsdescribed above in relation to any one of Figs . 8 to 11.

[0104] As shown in Figures 13, 14 and 15 , the immersion protection garment 210 has a region 219 in which a deflated inflatable bladder - or inflatable chamber - 252 (see Figure 16) is accommodated . The region 219, in the example shown, is generally U-shaped and has a central portion 232 that passes around the back of the wearer' s neck and two arms 234A and 234B extending from opposite left- and right-hand sides of the central portion 232 configured to lie over opposite sides in front of the wearer' s torso 231. The inflatable bladder 252 may include one or more sheets of material that comprise graphene ( for example, in combination with PU or TPU) .

[0105] The deflated bladder 252 has a similar shape and size to the region 219, so that deflated bladder 252 is also generally U-shaped and has a central portion that passes around the back of the wearer' s neck and with two arms extending from opposite left- and right-hand sides of the central portion configured to lie over opposite sides in front of the wearer' s torso 231. The deflated bladder 252 may be folded to fit in the region 219.

[0106] Other shapes and configurations of the region 219 and the bladder 252 are possible .

[0107] The region 219 is fitted with one or more inflation systems 233, such as a compressed gas cylinder for inflating the bladder 252 within the region 219. The inflation system 233 may be automatically triggered on contact with water and / or may be manually triggered by the aircrew member . The inflation system 233 may include graphene .

[0108] In the example shown, the arms 234A and 234B of the bladder 252 are attached to the waist belt 222 at strong attachment points 235A and 235B (see Figure 16 ) at the left- and right-hand sides of the wearer' s torso, respectively. This attachment may be by the waist belt 222 passing through arespective loop (not shown) attached to the underside of the left arm of the bladder and to the underside of the right arm of the bladder . The attachment points 235A and 235B form strong anchoring points when the bladder 252 is inflated. The waist belt 222 may be integrated into the garment 210.

[0109] A back strap 226 may be attached at its lower end to the waist belt 222 (e . g . by loop 240 - see Figure 14 and 16 ) at the centre of the rear torso and is attached to the bladder 252 at its upper end at the central portion 232 at the back of the neck. This may prevent the bladder 252 riding up over the wearer' s head when inflated. The back strap 226 may be threaded through the channel (not shown) of the immersion protection garment 210 to further locate the back strap 226. The back strap 226 may be integrated into the garment 210 or may be omitted (as shown in Figure 15 ) . The back strap 226 may include graphene . The loop 240 may include graphene .

[0110] As shown in Figure 16, the bladder 252 is packed deflated inside the outer surface (exterior or front layer) 250 of the immersion protection garment 210 , to protect the bladder 252 from damage . The outer surface 250 may comprise one or more panels like the first panel 30 and the second panel 32 described above, and j oined together in one or more of the ways described above . The inflation system 233 can be contained beneath the outer surface 250 or can be remote from the outer surface 250 and connected by a tube to the bladder 252 (e . g . by a Remote Inflation System, e . g . as described in the applicant' s patent GB2573474 ) .

[0111] An internal cover ( interior or rear layer) 256 can be fitted to protect the bladder 252 inside the garment . The internal cover 256 lies between the bladder 252 and the torso 231 of the wearer . The internal cover 256 is preferably substantially inelastic . The internal cover 256 may be formed from an inelastic woven material . The generally inelastic nature of the internal cover 256 means that it does not expandsignificantly when the bladder 252 is inflated . As a consequence, inflation of the bladder 252 applies pressure to the automatically releasable closure 254 , rather than expanding the internal cover 256. The internal cover 256 may include graphene . The internal cover 256 may comprise one or more panels like the first panel 30 and the second panel 32 described above, and j oined together in one or more of the ways described above .

[0112] Similarly, the outer surface (exterior surface) 250 of the garment 210 may also be formed of a substantially inelastic material, such as an inelastic woven material . The generally inelastic nature of the outer surface 250 means that it does not expand significantly when the bladder 252 is inflated. As a consequence, inflation of the bladder 252 applies pressure to the automatically releasable closure 254 , rather than expanding the outer surface 250.

[0113] Together, the internal cover 256 and the outer surface (exterior surface ) 250 of the immersion protection garment 210 form a pocket 259 within which the deflated bladder 252 is contained . The area where both the internal cover 256 and the outer surface (exterior surface) 250 are present corresponds to the region 219 in which a deflated inflatable bladder 252 is accommodated .

[0114] The internal cover 256 and / or the outer surface (exterior surface) 250 of the immersion protection garment 210 may be a graphene-containing sheet of material . The internal cover 256 and / or the outer surface (exterior surface) 250 may be formed by weaving together fibres , threads or yarn that contain graphene .

[0115] The internal cover 256 has a similar shape and size to the region 219, so that the internal cover 256 is also generally U-shaped and has a central portion that passes around the back of the wearer' s neck and with two arms extending from opposite left- and right-hand sides of the central portion configured to lie over opposite sides in front of the wearer' storso 231.

[0116] Openings 260 may be provided in the internal cover 256 at locations in each of its arms that correspond to the position of the waist belt 222. The waist belt 222 may pass through the openings 260 so that the strong attachment points 235A and 235B, where the arms and of the bladder 252 are attached to the waist belt 222 , are inside the pocket 259. A total of four openings 260 may be provided, two in each arm.

[0117] The outer surface 250 of the immersion protection garment 210 is provided with an automatically releasable closure 254 in the region 219, e . g . in the centre of the region 219. The automatically releasable closure 254 may be a "burst open" zipper, Velcro® or press studs etc . The automatically releasable closure 254 may be a slide fastener as described in the applicant' s patent publication GB2588110. The automatically releasable closure 254 extends along the two arms 234A and 234B and the central portion 236, behind the wearer' s neck .

[0118] When the inflation system 233 is activated, the outer surface 250 will automatically open by way of the automatically releasable closure 254. When the inflation system 233 is activated (either manually or automatically) , the inflating bladder 252 acts on the automatically releasable closure 254 to open it . The pressure generated by inflation of the bladder 252 causes the automatically releasable closure 254 to open . When the automatically releasable closure 254 opens, the bladder 252 passes through the opening as further inflation occurs . Figures 26, 27 and 28 show the bladder 152 when fully inflated, after the releasable closure 154 has opened.

[0119] Figures 17 , 18 and 19 depict the bladder 252 after it has moved from the interior of the garment 210 (as shown in Figures 13 to 16) to the exterior of the garment 210 as it inflates . The inflated bladder is positioned over the wearer' s chest and behind the wearer' s neck and provides buoyancy,thereby preventing drowning in the event that the aircrew member makes an emergency landing in water .

[0120] The internal cover 256 or the outer surface 250 may be opened by a releasable closure 258 (e . g . formed by press studs, a conventional zipper or Velcro®) to allow the bladder 252 to be removed from the garment 210 for maintenance or repair . Unlike the automatically releasable closure 254 , the releasable closure 258 is not configured to open automatically when the bladder 252 is inflated .

[0121] In this embodiment, instead of using a conventional single layer of material that consists of a textile supporting sheet ( for example nylon or polyester with graphene) coated or laminated on the inside with a sheet of flexible gas (e . g . air) impermeable polymer such as neoprene or polyurethane with graphene, the two separate layers may be provided (e . g . a textile outer layer and the separate inner polymer layer) to form the bladder 252. The textile outer layer and / or the separate inner polymer layer may include graphene .

[0122] The use of two separate layers to make the bladder 252 may result in a bladder construction that is lighter, more compact when packed and stronger .

[0123] As shown in Figures 20-C, a textile outer layer 352 ( for example nylon or polyester) of the bladder 252 may be formed of two sheets of material that are stitched together . An upper sheet of material 353A has an outer surface 357A and an inner surface 357B . The lower sheet of material 353B has an outer surface 358A and an inner surface 358B . The sheets 353A and 353B are connected at an edge region 359 of each of the sheets so that the distal inner surface of one of the sheets overlaps the distal outer surface of the other one of the sheets, the distal surfaces being stitched together, as indicated at 361. In the arrangement shown the distal inner surface 357B of the upper layer 357A is positioned to face the distal portion of the outersurface 358A of the lower layer 353B, these layers being held in contact by the stitching 361.

[0124] An inner layer 355 of the bladder 252 is formed by two sheets 354 of flexible gas impermeable material . The two sheets are joined by a weld 356.

[0125] In this embodiment the outer textile layer 352 can be stitched ( in sheer) around its edge and this creates a much stronger seam than the welding . The inner layer of the bladder 352 is made to be oversize or made from a polymer including graphene that can stretch and so the welded edge 356 never comes under tension, as shown in Figures 20A-C . Although the inner layer 355 of the bladder 352 may be of generally the same shape as the outer textile layer 352 , the inner layer 355 of the bladder 352 may be of generally larger size . The inner layer 355 of the bladder 352 may be made of a sufficiently large size so that, when inflated within the outer textile layer 352 , the inner layer 355 of the bladder 352 fills the internal volume of the outer textile layer 352 without any stretching of the inner layer 355 of the bladder 352 occurring, and the tension is taken up by the outer textile layer 352 . If the inner layer of the bladder 352 is made oversized, the inner layer 355 of the bladder 352 may be made of an inextensible and / or inelastic material . It is advantageous for the tension to be taken up by the outer textile layer 352 , as it is stronger than the inner layer of the bladder 352 .

[0126] Preferably, the outer textile layer 352 is made from a lightweight "ripstop" material and is coated with a lubricant such as silicon. The outer textile layer 352 may be a lightweight material that includes graphene and is coated with a lubricant such as silicone . This produces an extremely strong material with high tear strength, and also, because the surface has a very low surface friction, the inner polymer layer 355 will slide easily over it which results in a very compact lifej acket .

[0127] Ripstop fabrics are woven fabrics, e . g . made of nylon, using a special reinforcing technique that makes them resistant to tearing and ripping . During weaving, relatively thick reinforcement threads are interwoven at regular intervals in a crosshatch pattern. The intervals are typically 5 to 8 mm. Thin and lightweight ripstop fabrics have a 3-dimensional structure due to the thicker threads being interwoven in thinner cloth . The fabric may contain graphene in addition to, or instead of ripstop material .

[0128] In the above embodiment the LPU bladder is mounted on the interior face of a jacket or vest, suit etc . (i . e . a garment ) , but on activation of the inflation moves from the interior to the exterior of the garment via an automatically opening zipper or Velcro or press studs etc . as a result of the bladder being pressurised.

Claims

1. CLAIMS1. An immersion protection garment having at least one sheet of flexible material that includes graphene .2 . The immersion protection garment of claim 1, wherein the graphene included in the sheet of flexible material comprises the graphene nano platelets .

3. The immersion protection garment of claim 1 or 2 , wherein the sheet of material further includes a flexible polymer .4 . The immersion protection garment of claim 1 , 2 or 3, wherein the sheet of material includes polyurethane, PU .5 . The immersion protection garment of any one of claims 1 to 4 , wherein the sheet of material includes thermoplastic polyurethane, TPU.

6. The immersion protection garment of any one of claims 1 to 5 , wherein the sheet of material includes between 1 and 10% graphene by weight, preferably 1.5% graphene by weight .7 . The immersion protection garment of any one of claims 1 to 6, wherein the sheet of material has a thickness of between 100 and 150pm.8 . The immersion protection garment of any one of claims 1 to 7 , wherein the sheet of material is fluid impermeable .

9. The immersion protection garment of any one of claims 1 to 8 , wherein the sheet of material is moisture-vapour permeable .

10. The immersion protection garment of any one of claims 1 to 9, wherein the sheet of material is formed from fibres , threads or yarn that contains graphene .

11. The immersion protection garment of claim 10 , wherein the fibres, threads or yarn are woven together to form thesheet of material .12 . The immersion protection garment of any one of claims 1 to 11 , including first and second sheets of material, one of which is said at least one sheet of flexible material that includes graphene .

13. The immersion protection garment of claim 12 , wherein the first sheet of material is arranged to support the second sheet of flexible material .14 . The immersion protection garment of claim 12 or 13, wherein the second sheet of flexible material is bonded to the first sheet of material .15 . The immersion protection garment of claim 12 or 13, wherein the second sheet material is separate from the first sheet of material .

16. The immersion protection garment of any one of claims 12 to 15 , wherein the first and / or second sheet of flexible material includes graphene .17 . The immersion protection garment of any one of claims 12 to 16, wherein the first and second sheet of flexible material comprise respective panels of the garment that are j oined together .18 . The immersion protection garment of claim 17 , wherein an edge region of the first sheet of sheet of flexible material is overlapped with an edge region of the second sheet of flexible material and the edge regions are welded or bonded together .

19. The immersion protection garment of claim 17 , wherein an edge region of the first sheet of sheet of flexible material and an edge region of the second sheet of flexible material are oriented so that they extend generally parallel to each other and are welded or bonded together .

20. The immersion protection garment of claim 18 or 19, wherein parts of the first sheet of sheet of flexible material and parts of the second sheet of flexible material that are welded together include TPU or PU.

21. The immersion protection garment of claim 17 , wherein an edge region of the first sheet of sheet of flexible material is overlapped with an edge region of the second sheet of flexible material and the edge regions are stitched together .22 . The immersion protection garment of claim 21, wherein the edge region of the first sheet of sheet of flexible material and / or the edge region of the second sheet of flexible material is folded over itself to form a hem prior to stitching the edge regions together .

23. The immersion protection garment of claim 21 or 22 , wherein the first sheet of sheet of flexible material and / or the second sheet of flexible material comprise fibres, threads or yarn are that are woven together to form the sheet of material, and wherein a layer of material is laminated onto the first sheet of sheet of flexible material and the second sheet of flexible material and the join therebetween .24 . The immersion protection garment of claim 21 or 22 , wherein the first sheet of sheet of flexible material and / or the second sheet of flexible material comprise fibres, threads or yarn are that are woven together to form one layer of the sheet of material, which one layer is bonded to a second layer comprising TPU or PU, and wherein a piece of material is fixed onto the first sheet of flexible material and the second sheet of flexible material in a region of the j oin therebetween .25 . The immersion protection garment of any one of claims 1 to 24 , wherein the immersion protection garment is a dry suit or submarine escape suit .

26. The immersion protection garment of any one of claims 1 to 25 , including an inflatable chamber that functions as a lifej acket or life preserver unit, LPU .27 . The immersion protection garment of claim 26, wherein the inflatable chamber is located under an outer garment layer of the garment when deflated, wherein the outer garment layer includes a line of weakness that opens due to pressure applied by partial inflation of the inflatable chamber to allow full inflation of the inflatable chamber outside the outer garment layer of the garment .28 . The immersion protection garment of claim 27 , wherein the inflatable chamber is located between the outer garment layer and an inner garment layer of the garment when deflated .

29. The immersion protection garment of claim 27 or 28 , wherein the sheet of flexible material that includes graphene forms the outer garment layer and / or the inner garment layer .

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