WO2006036072A1

WO2006036072A1 - Impact resistant laminates

Info

Publication number: WO2006036072A1
Application number: PCT/NZ2005/000248
Authority: WO
Inventors: Anton Radaich
Original assignee: Body Armour (1995) Limited
Priority date: 2004-09-27
Filing date: 2005-09-26
Publication date: 2006-04-06

Abstract

As a laminate constituent, a cushioning and/or impact layer (1) configured to provide a close array of regions (4) linked at least one to another by said material through integral links (5). Preferably adhered on at least one major face thereof, a flexible sheet material capable of being attached or used for attachment.

Description

IMPACT RESISTANT LAMINATES TECHNICAL FIELD

The present invention relates to impact resistant, deformable, resilient, protective and/or absorbing ("resistant") laminates, padding forms or structures, assemblies including such impact resistant laminates or padding forms or structures, and related methodologies and uses as well as the products themselves.

BACKGROUND ART

Various forms of impact resistant material is available including single or multiple material including materials whether as a laminate, a complex matrix, a varied density form, etc or otherwise.

Of particular interest is the sporting market where impact protection for certain areas of a sportsman's body might be required. For example, in the area of rugby union, impact protection is frequently sought in headgear, shoulder and/or body padding or in the garments. Similar protection forms have application in fields as diverse as cricket, motorcycle racing, cycling, skiing, rugby league, American football, etc.

Suitable laminates, materials, structures, assemblies etc useful in sport will also have application in non sporting activities (e.g. motorcycling, cycling etc) as well as in respect of sports. One particular interest in the area of impact resistance is the lightness and/or flexibility of the resultant item so as not to restrict the wearer and/or the ability to play the game.

In UK Patent Application GB 2352208 A there is disclosed a flexible material formed reliant on discreet impact resistant/absorbing elements on a resiliently stretchable substrate. A flexible material is disclosed where a layer of separate resilient elements are joined to a flexible fabric or film substrate with the spaced separate elements being distributed on the substrate with a density of between 250 and 8000 elements per square metre. Manufacture of such a flexible material requires the specialised procedure disclosed therein.

The present invention recognises a potential advantage from a manufacturing and/or resultant product point of view from a provision of a lattice of a resilient material as the impact absorbing medium to be affixed to sheet such as a stretchable fabric, film or some mechanical equivalent (e.g. a cured coating) or to be sandwiched between such sheets (and/or to be optionally be incorporated by sewing, adhesion or otherwise into a garment or having one or both of the sheets as part of a garment). Irrespective of whether or not the invention is directed to a garment, a bare pad or to a protector such as headgear, shoulder pads, thigh pads, chest pads or the like, the present invention confers manufacturing advantage particularly where the lattice is to be cut from a pre-formed sheet of the resilient material, be it a foam or other type impact absorbing material.

It is therefore to such products and related methods, uses, assemblies, etc that the present invention is directed as a means of providing the public at least with a useful choice.

As used herein the term "resistant" and any variation thereof refers to any one or more of the meanings normally ascribed to a pad for conferring a measure of impact protection (e.g. impact resistant, deformable, resilient, protective, and/or absorbing). It should preferably deform under impact and return at least substantially to its initial condition after impact (irrespective of whether or not there is any energy absorption by such deformation, although preferably there is some absorption).

As used herein the term "sheet" refers to non perforate sheets (such as of a film, fabric, or combinations of such and other materials) but may in some forms refer to perforate, netting, or the like "sheet" materials, or assemblies including such materials. It can include an in situ formed "sheet" e.g. from a one or two pot compatible curable and/or dryable composition in which part of the lattice is dipped and/or otherwise coated with some spanning of the resultant composition material between the lattice regions. As used herein "region" or "regions" refer to areas of any particular shape and irrespective of whether or not of mixed shapes throughout the lattice that are interconnected directly and indirectly as a whole. More preferably "lattice" refers to a resultant structure having inherent flexibility beyond that hitherto that existed between such areas as a consequence of removal of material so as to provide a close array (preferably as hereinafter described) of such regions or areas linked by one or more integral bridge provided by the material(s) with a proximate region or proximate regions.

Reference hereinafter to a "maximum dimension" preferably does not include the depth of any such precursor sheet from which the lattice may have been prepared by die cutting, laser cutting or any equivalent. The present invention however does not exclude a moulded form of the lattice.

As used herein "close array" preferably means spacing less (preferably much less than) the maximum dimension of each region of the array.

As used herein the term "and/or" means "and" or "or", or both. As used herein the term "s" following a noun includes as might be appropriate the singular or plural forms of that noun.

As used herein the term "proximate" refers to one or more regions of substantially similar distances or same distances from the first region.

DISCLOSURE OF INVENTION

In an aspect the invention is a lattice of an impact deformable and resilient material defining a close array of regions linked at least one to another by said material, the material links not having been affixed after the defining of the close array of regions. In another aspect the present invention consists in a lattice of an impact deformable and resilient material defining a close array of regions (of the same and/or varied forms) linked at least one to another by said material, the material links not having been affixed after the defining of the close array of regions and the regions preferably (at least predominantly) having a greatest dimension greater than the linked distance between proximately linked regions.

Preferably the lattice is derived from a precursor sheet having a depth and that depth is not the direction at which said greatest dimension is to be measured.

Preferably some of the regions are linked to all of their proximate regions whilst others are linked to some or one only of the proximate regions. This enables by selective linking some more linked areas articulating on fewer links connecting directly and indirectly to an adjacent linked area of regions.

Preferably the array of the regions and the linking thereof is such as to maximise flexibility for the functional purpose of the lattice.

Preferably said lattice is of a foam or non foam material capable of being resistant to impact.

Preferably said material of the lattice is thermo formable but not necessarily so.

Preferably said material of the lattice is selected from any one or more of a material representable as a stable flexible material. Typical of any such material is one or more of PE, PU, PVC, and EVA. Other flexible materials can be of a synthetic or partly synthetic nature and/or of a natural material (e.g. rubber). Examples include foam or non foam forms of any such flexible material preferably being of a material capable by heating of having adhesion with a thermofilm adhesive but not necessarily so. The material preferably has existed as a sheet from which the lattice is capable of being defined by die cutting, laser cutting, or other equivalent procedure preferably to leave the form required for the purpose including preferably the periphery. Optionally a peripheral surround can be left after any such die cutting, laser cutting and/or the like or can be provided by fabrication. Preferably however there is no such continuous surround with preferably there being intrusions between whole or part regions from the periphery of the lattice. In some forms a mixture of materials can be utilised whether as a laminate or a mixed matrix to provide said material of the lattice. In some forms it can be partially or fully foamed although in other forms it is not foamed at all.

In a particularly preferred form the material is a polyethylene rubber of, for example, 35 kg per cubic metre but could be, in less preferred forms, a PE material of, say, 30 or 60 kg/m3.

Preferably the PE material is totally unfoamed and is unlaminated prior to the lattice forming process save optionally with, and preferably with, a thermofilm adhesive on one side, and preferably both sides, of the sheet prior to a cutting of the lattice.

Preferably a clicking press and knife tool is used for the forming of the lattice from a precursor sheet.

In some forms of the present invention (less preferred) the precursor sheet material to be transformed into the lattice can be other than of constant cross thickness if particular regions of greater thickness are desired and/or allowable. Such provision however may require some lamination to achieve that effect and/or moulding. If a moulding process is involved it could instead be used directly to form the lattice.

In a further aspect the present invention is as a laminate constituent, a cushioning and/or impact layer of a material configured to provide a close array of regions linked at least one to another by said material. Preferably the constituent is a lattice as aforesaid.

In a further aspect the present invention is a protective construction, said construction comprising or including a lattice or laminate constituent as previously defined, and adhered on at least one major face thereof, a flexible sheet material (e.g. a fabric) preferably capable of being attached or used for attachment.

Preferably there is a similar or dissimilar flexible sheet material on each major face.

Preferably one or both sheets of flexible sheet material are more extensive than the lattice or constituent. In another aspect the invention is, a method of forming an impact resistant region of a garment, protective or sporting item, said method comprising or including associating to a flexible sheet a lattice of an impact deformable and resilient material defining a close array of regions linked one to another by said material. In another aspect the invention is a protective region of an item to be worn by a user, the region having a lattice as defined formed by die cutting of a laminate or association of said impact deformable and resilient material and a thermofilm adhesive which has, reliant on the thermofilm adhesive, been affixed to a fabric or like panel already or subsequently incorporated into the item. Accordingly in another aspect the present invention consists in a method of forming an impact resistant region of a garment, pad or pad structure, a protector or a sporting item, said method comprising or including associating to a flexible sheet a lattice of an impact deformable and resilient material defining a close array of regions linked one to another by said material. Preferably said flexible sheet is a resiliently stretchable material.

Preferably said lattice is interposed between two such flexible sheets.

Preferably the association to the at least one flexible sheet is by adhesion and/or heating.

Most preferably interposed between said lattice and the flexible sheet(s) is a thermofilm capable by application of heat directly or indirectly thereto of adhering to both a said flexible sheet and said lattice.

In some forms of the present invention rather than a thermofilm on one or both sides alternatives include flame bonding, hot melt adhesive, water based adhesives, MEK adhesive, solvent based adhesives. An example of a suitable thermofilm is that under the XRO™ brand. Preferably said lattice is of one or more materials whether as a laminate or otherwise.

Preferably said lattice is a lattice defined by die cutting, laser cutting or otherwise from a sheet of the material.

Preferably the lattice as a sheet is very much more thick than said flexible sheet or said flexible sheets e.g. preferably at least a factor of five times the thickness and preferably at least ten times the thickness.

Preferably said lattice is as previously defined.

In another aspect the invention is a product of the aforementioned method. BRIEF DESCWPTION OF DRAWINGS

Preferred forms of the present invention will now be described with reference to the accompanying drawings in which:

Figure 1 shows a rectangular piece of a single material (e.g. PE) that can be used to provide the lattice or constituent,

Figure 2 shows how a thermofilm can be applied, and preferably is applied to each face, of the material of Figure 1, heat if necessary being used to attach the thermofilm on each side of the material of Figure 1,

Figure 3 shows a lattice defined by die cutting through the resultant product of Figure 2 cutting through the thermofilm (not shown in Figure 3) on both sides thereof and leaving a lattice which, in this case, is primarily of hexagon shaped regions linked in some cases to three nodal connections (i.e. 3 links to a node) each of which nodal connection is to two other hexagonal regions,

Figure 4 shows the lattice of Figure 3 being laid on to a fabric suitable as part of a garment and which will enable sewing or attachment thereof into a harness, garment or the like,

Figure 5 shows the product of Figure 4 being overlaid with a further flexible sheet material (e.g. preferably a material the same as or different from that shown in Figure 4),

Figure 6 shows the final product of Figure 5 post heat pressing, Figure 7 shows in a press the material with its thermofilm lamination underneath a cutting die,

Figure 7A shows the press applying pressure to the cutting die,

Figure 8 shows the cutting die having passed through the laminated material just prior to uplifting of the press, thereby to provide, after removal of waste, a product as shown in Figure 3,

Figure 9 shows an arrangement as, for example, in Figure 4 (this time with the flexible material over the lattice) about to have the thermofilm adhered thereto by a heated press part,

Figure 10 shows the heated press on the flexible material of Figure 9, Figure 11 shows the resultant product of the process of Figure 10 subsequent for a further heat application of fabric in this case as shown in Figure 5,

Figure 12, similarly to as shown in Figure 10, shows the heat attachment of the fabric to the thermofilm, Figure 13 shows in a similar manner to Figure 4 an arrangement where some of the nodal links shown in Figure 4 have been removed thereby providing greater flexibility, and

Figure 13 A shows intrusions for some of the peripheral parts of the lattice.

In the preferred form of the present invention a product capable of being sewn as a pad into a garment (e.g. shoulder pads, chest pads, thigh pads) is to be provided but this need not be the only outcome.

As shown in Figure 4 a lattice 1 is defined from a material as depicted in Figure 2 being of the relatively thick (e.g. near 5 or near 10mm thick) material 2 having attached to each side thereof a thermofilm sheet 3 such as for example 1 as previously mentioned. It is this sandwiched product that is die cut to provide a lattice substantially as shown in Figure 4 where regions 4 are linked by integral links 5 which, in the case of Figure 4, are of nodally connecting links where a link from one region 4 is linked directly to a link of two others, save near peripheral regions. Even shown in Figure 4, and more so in Figure 13, are the prospect of intrusions 6 at the edges, which intrusions 6, if desired, can be into the regions 4 themselves at or adjacent the edge. Indeed many of the regions 4 (e.g. such as Figure 4A in

Figure 13) are cut to provide the total area of lattice required.

Shown in Figure 13 is an option of rendering the product more flexible by selectively designing the knife so as to reduce the number of internal links thereby making some areas of linked regions more easily able to articulate as an area relative to another area of other more tightly linked regions. Such removal of some of the links can be seen in areas such as 7.

In the form however shown in Figure 4 the lattice 1 is preferably provided simply by die cutting as shown in the sequence Figures 7 through 8 with preferably infills in regions of the knife corresponding to the Y shaped cut outs 8 (as shoulders or otherwise) popping to some extent the waste material from the plane of the lattice for their subsequent easy removal. Any suitable form of die cutting knife 9 can be utilised.

Subsequent to the formation of the lattice 1, still with its layers 3 on each side thereof but corresponding strictly to the overlying and underlying regions of the material 2, it is then possible by heat pressing to apply first and then on the other side a flexible sheet material 10 and then 11 reliant on the underlying thermofilm 3 for appropriate bonding. This could instead be simultaneously achieved. This results in a product as shown in Figure 5 capable of being incorporated into the end product or which can itself be an end product with appropriate fixings attachments. Ordinarily however some peripheral attachment by sewing, adhesion or the like of the regions 12 would associate the product with a surround of some sort. A person skilled in the art will appreciate that a great number of options exist for the present invention.

Whilst some forms of the present invention have been described with reference to the accompanying drawings, it should be appreciated that the regions can be circular, hexagonal, triangular, square, multi-faceted or of any other form provided there is some semblance of linking of each one to at least one other. It matters not if they differ in their form one to another although in preferred forms of the present invention, save-where-an-exterior perimeter may interfere with any regular patterning, preferably there is some measure of regularity albeit with some of the regions optionally having only a few links to proximate regions whilst some may have links to all proximate regions.

The preferred manufacture has been described with reference to the accompanying drawings but other procedures could instead be used.

In the preferred form of the present invention the flexible sheet to act as a substrate of the lattice is a nylon or Lycra type fabric but it can be of any other suitable form e.g. whether fabric, netting, film, or the like.

Preferably the lattice forming material is a die cuttable polyethylene rubber.

International Rugby Board rules currently restrict the thickness of impact padding to

10mm in some areas (e.g. the head, the shoulders, etc) and restricts for other areas down to a

5mm thickness. The present invention, by way of example, therefore enables compliance with both requirements by an appropriate choice of materials from which the lattice is formed.

Claims

I . A lattice of an impact deformable and resilient material defining a close array of regions linked at least one to another by said material, the material links not having been affixed after the defining of the close array of regions.

2. A lattice of claim 1 have two spaced parallel faces.

3. A lattice of claim 1 or 2 wherein the regions at least predominantly have a greatest dimension greater than the linking distance.

4. A lattice of any one of the preceding claims wherein the regions are of the same form.

5. A lattice of claim 3 wherein away from a perimeter of the lattice the regions are of the same form.

6. A lattice of any one of the preceding claims wherein the links are narrow but full depth bridges.

7. A lattice of claim 3 derived from a precursor sheet having a depth and that depth is not the direction at which said greatest dimension.

8. A lattice of any one of the preceding claims wherein some of the regions are linked to all of their proximate regions whilst others are linked to some or one only of the proximate regions.

9. A lattice of claim 8 wherein the array of the regions and the defined linking thereof has been to provide flexibility for the functional purpose of the lattice.

10. A lattice of any one of the preceding claims wherein said lattice is of a foam or non foam compliant material capable of being resistant to impact.

I I. A lattice of claim 10 wherein said material of the lattice is thermoformable.

12. A lattice of claim 10 or 11 wherein the material is one or more of PE, PU, PVC, EVA, a synthetic rubber or partly synthetic rubber.

13. A lattice of any one of the preceding claims that has existed as a sheet from which the lattice has been defined by die cutting, laser cutting, or other equivalent procedure.

14. A lattice of any one of the preceding claims wherein it is of a mixture of materials, can be utilised whether as a laminate or a mixed matrix.

15. A lattice of any one of the preceding claims where its material or a material thereof is partially or fully foamed.

16. A lattice of claim 14 wherein the material is a polyethylene rubber.

17. A lattice of claim 15 which existed as a sheet, prior to lattice forming, of polyethylene rubber of about 35 kg per cubic metre.

18. A lattice of any one of claims 1 to 14 wherein the material prior to lattice forming has been a PE material of, about 30.

19. A lattice of any one of claims 1 to 14 wherein the material prior to lattice forming has been a PE material of, about 60.

20. A lattice of any one of claims 1 to 14, 17 and 18 wherein the material prior to lattice forming is PE material that is totally unfoamed and is unlaminated prior to the lattice forming process but optionally may have a thermofilm adhesive on one side, or both faces of the sheet prior to a cutting of the lattice therefrom.

21. A lattice of any one of the preceding claims where a clicking press or knife tool or both has been used for the forming of the lattice from a precursor sheet.

22. As a laminate constituent, a cushioning and/or impact layer of a material configured to provide a close array of regions linked at least one to another by said material.

23. A protective construction, said construction comprising or including a lattice as claimed in any one of claims 1 to 21 , and adhered on at least one major face thereof, a flexible sheet material capable of being attached or used for attachment.

24. A construction of claim 23 wherein the flexible sheet material is a fabric.

25. A construction of claim 23 or 24 wherein there is a similar or dissimilar flexible sheet material on each major face.

26. A construction of claim 23 wherein one or both sheets of flexible sheet material are more extensive than the lattice or constituent.

27. In a method of forming an impact resistant region of a garment, protective or sporting item, associating to a flexible sheet a lattice of an impact deformable and resilient material defining a close array of regions linked one to another by said material.

28. A method of claim 27 wherein said flexible sheet is a resiliently stretchable material.

29. A method of claim 28 wherein said lattice is interposed between two such flexible sheets.

30. A method of claim 27 the association to the at least one flexible sheet is by adhesion.

31. A method of claim 30 which has included interposing between said lattice and the flexible sheet(s) a thermofilm capable by application of heat directly or indirectly thereto of adhering to both a said flexible sheet and said lattice.

32. A method of claim 27 wherein said lattice is defined by die cutting, laser cutting or otherwise from a sheet of the lattice forming material or materials.

33. A method of any one of claims 27 to 32 wherein a peripheral region of said sheet is fixed to a panel of the item.

34. A product of a method of any one of claims 27 to 33.

35. A protective region of an item to be worn by a user, the region having a lattice of claim 1 formed by die cutting of a laminate or association of said impact deformable and resilient material and a thermofilm adhesive which has, reliant on the thermofϊlm adhesive, been affixed to a fabric or like panel already or subsequently incorporated into the item.