NZ239582A - Mattress having integral barrier covering impermeable to liquid water but permeable to water vapour - Google Patents

Abstract

A mattress or other supporting unit comprises a number of layers of filling (1; 5, 7, 5', 7') and an outer covering (4, 6, 10). A barrier (4, 6, 9, 18, 19; 21, 22, 23) to the passage of infectious agents is provided adjacent to at least one of the layers and within the outer covering.

Description

239 582 Patents Form 5 iW-y , j Pn-: ,/JWcWoOyPV Ai*.lC$l/00y | Gfe&lJ&rr....... ...... > I 2 6 .JUL TO . .. /3*2- N.Z. No.

NEW ZEALAND Patents Act 1953 COMPLETE SPECIFICATION N.2. '■ . | 29 AUG 1991 RECfiVEC A MATTRESS OR OTHER SUPPORTING UNIT We, SLUMBERLAND PLC, a British company of Holly ville, Holmfirth Road, Greenfield, Oldham, OL3 7DR, England, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - - 1 - (Followed by 1A) 239 5 8 2- iA A MATTRESS OR OTHER SUPPORTING UNIT This invention relates to mattresses and other supporting units.

The invention is particularly applicable to mattresses and to supporting units constituting mattress-components, that is to units of the kind which can be stacked or otherwise assembled with an 10 additional unit or with additional units to form an assembly of supporting units which together constitute a mattress, it being understood that the additional supporting unit or at least one of the additional units may be similar to the supporting unit with which the 15 present invention is primarily concerned.

In addition to its being concerned with mattresses and mattress-components the present invention is also applicable to other kinds of supporting units such as 20 pillows and cushioning for seats.

It is known that the house dust mite thrives in conditions existing inside a standard mattress and that skin shed by an occupant of a bed provides a convenient 25 food source. It is accepted that an allergic response to the house dust mite or faeces thereof can aggravate or cause an asthmatic reaction in an occupant. In GB-A- 213 053 we describe a removable cover for a mattress the cover in use providing a barrier.- to the 30 passage of mites between the interior of a mattress and the food source, and so depriving the mites of their food source.

Recent research has shown that house dust mites 35 may also be implicated in the transmission of a number of diseases particularly those which can be passed on 9 C> 9 v.-,''' through a fluid vector. These findings will be of particular concern in institutions, such as hospitals and hotels, where the same bed may be occupied by a large number of people.

According to a first aspect the present invention consists in a mattress or other supporting unit comprising a number of layers of filling/ an outer covering, a barrier to the passage of infectious agents positioned adjacent to at least one of the layers within the outer covering, and a permanent non-removable sealed container enclosing at least some of the layers of filling, in which the barrier is defined by a portion of the container and comprises at least one layer of material forming an integral component part of the mattress, and at least a substantial portion of the said portion of the container is vapour permeable, that is impermeable to liquid water, but permeable to water-vapour.

A particular advantage of a mattress in accordance with the present invention is that a barrier is provided to the passage of the house dust mite and its antigen.

In a conventional mattress the filling may comprise a series of layers of materials such as wool felts, cotton, foam, polyester fibre, and wool. Traditionally the outer covering comprises a fabric ticking such as damask.

Preferably the barrier comprises at least one layer of material, at least a substantial portion of which is vapour permeable, that is impermeable to liquid water but permeable to water-vapour.

The vapour permeable material may comprise polyethylene film such as that marketed under the trade mark PLATILON. 2 K XeS Alternatively the vapour permeable material may comprise a textile fabric provided with a coating that is impermeable to liquid water but permeable to water 239582 3 vapour. A suitable material is marketed under the trade mark "VENTFLEX".

Another suitable material is sold under the trade 5 mark "GORE-TEX" and comprises a textile fabric laminated by a bonding process to a micro-porous material.

The materials referred to above are merely 10 examples of materials suitable for use in a mattress or other supporting unit in accordance with the present invention. Other materials which fulfil the requirement of providing a barrier to infectious agents may be substituted for the materials referred to.

The mattress may comprise a spring unit supporting a number of layers of filling. It is envisaged that a sheet of vapour permeable material may be incorporated at any desired location in the mattress construction. 20 It is preferred to position the sheet as close to the occupant as possible so as to reduce the habitat available to the house dust mite. Suitable sealing means should also be provided in the sides and base of the mattress so as to seal off the interior of the 25 mattress.

In one embodiment a layer of vapour permeable material may be incorporated above and below the spring unit, a suitable sealing means being provided along 30 each side of the spring unit. The sealing - means may comprise a panel of vapour permeable material or a panel of an air tight material. Alternatively upper and lower layers may extend such that their peripheries may be sealed together. 239 5 4 In another embodiment at least an upper layer of vapour permeable material may be incorporated into the layers of filling. The upper layer of vapour permeable material may be incorporated into the filling in a 5 process referred to as quilting in which a number of layers of filling and the ticking are joined together in such a way as to give a lofted appearance. It is necessary to ensure either that the upper layer of vapour permeable material is not punctured during the 10 quilting process or that if it is it is adequately sealed after the quilting process is complete.

Alternatively a number of layers may be quilted together to form a quilted layer and after the quilting 15 process is complete a layer of vapour permeable material may be laminated to the underside of the quilted layer.

In other embodiments the upper layer of vapour 20 permeable material may be stretched over a layer of filling in a conventional manner.

A lower layer of vapour permeable material may be incorporated below the spring unit. The lower layer 25 may be laminated to a layer of filling or to the inner side of the ticking or may be stretched over the spring unit in a conventional manner.

From a second aspect the present invention 30 consists in a mattress or other supporting unit comprising a flexible, yielding body enclosed within a container, at least one main face of the container, constituting a working face, comprising a flexible film of a material that is impermeable to liquid water but 35 is permeable to water-vapour. 239 582 The working face of the mattress or other supporting unit is that face of the unit which the user bears against when the unit is in use? for example, the upper main face of a mattress is the working face of 5 the mattress, while the forwardly directed face of an upright seat-back is the working face of the seat-back.

The flexible material may comprise polyethylene film. A flexible material suitable for use in carrying 10 out the present invention is a polyurethane film 30u thick marketed under the trade mark PLATILON by Plate Bonn G.m.b.h. of Bonn, West Germany. That film has a water-vapour permeability of more than lOOOgm /24h at 37°C and 100% relative humidity as measured by the 15 Payne's cup method, a method described in: Payne HS. The permeability and structure of films. Off. Dig Fed Paint Varnish Production Clubs 1936; 8: 297-304.

The container may be fully closed or substantially 20 fully closed so that in normal use the amount of air or other gas within it remains constant or alters only very slowly with the result that the supporting unit tends to provide at least some pneumatic support for a user of the unit.

An additional advantage of using a container that is fully closed or substantially fully closed is that any bed mites or the like that might enter the container or be trapped inside the container are 30 normally prevented from colonising the body owing to the fact that they are starved of nourishment.

Nevertheless, in an alternative construction the container is not fully closed so that in normal use the 35 supporting unit tends not to provide any pneumatic 239582 6 support for a user or tends to provide such support for no longer than a short period.

The flexible, yielding body within the container 5 may be of any suitable nature and may be of unitary or compound form. In particular it preferably comprises a layer of resilient foam material of which at least one of the main faces is of so-called 'convoluted' form, that is the face is shaped to afford a regular array of 10 peaks and hollows; those formations or 'convolutions' are preferably of a rounded form so that the surface of the face (apart from the marginal edges) includes no sharp or angled edges but is of a continuously and smoothly undulating shape.

The body may consist solely of a layer of resilient foam material, at least one main face of which is preferably of convoluted form. Alternatively the body may consist solely of a pad of fibrous 20 material such as a pad of polyester fibre. Alternatively the body may comprise two or more components; for example it may comprise a layer of foam material and a pad of fibrous material, the pad preferably being closer than the foam material to the 25 working face of the unit. That main face of the layer of foam material adjacent to the pad is preferably of convoluted form. A flexible diaphragm may be provided between the layer of foam material and the pad of fibrous material this being particularly desirable when 30 the face of the layer of foam material adjacent to the pad is of convoluted form; the diaphragm may conveniently comprise a film or films of material that is impermeable to water but permeable to water-vapour, the material preferably being similar to that from 35 which the working face of the container is formed. 23958E 7 From a third aspect the present invention consists in a mattress or other supporting unit comprising a flexible, yielding body enclosed within a container in such a manner that in normal use the amount of air or 5 other gas within it remains constant or alters only very slowly with the result that the supporting unit tends to provide at least some pneumatic support for a user of the unit, at least one main face of the container, constituting a working face, comprising or 10 containing a flexible material that is impermeable to water but is permeable to water vapour.

A supporting unit in accordance with this third aspect of the present invention, unlike a supporting 15 unit in accordance with the second aspect of the present invention, necessarily tends to provide some pneumatic support for a user of the unit but has a working face that is not necessarily in the form of a film. In fact the working face may be afforded by a 20 flexible sheet material of the kind comprising a textile fabric provided with a coating of which is impermeable to liquid water but is permeable to water-vapour. Suitable materials are those marketed under the trade marks "VENTFLEX" and "GORE-TEX".

Apart from those differences, a supporting unit in accordance with the third aspect of the present invention may incorporate any of the optional or preferred features outlined above in relation to a 30 supporting unit in accordance with this second aspect of the present invention.

Embodiments of the present invention will now be described in more detail, by way of example, with 35 reference to the accompanying drawings, in which:- 239582 8 Figure 1 is a diagrammatic cross-section through a supporting unit embodying the present invention; Figure 2 is a diagrammatic cross-section through 5 another form of supporting unit embodying the present invention; Figure 3 is a cross-section through another form of supporting unit embodying the present 10 invention; Figure 4 is a cross-section through a mattress embodying the present invention; and Figure 5 is a cross-section through another form of mattress embodying the present invention.

The supporting unit shown in Figure 1 comprises a rectangular body of flexible and resilient foam 20 material 1 of which the underside 2 is planar but the upper surface 3 is of convoluted form, as referred to above. The body 1 is enclosed within a container 4 comprising a sealed bag made of polyurethane film 30u thick that is impermeable to liquid water but permeable 25 to water-vapour, the film being of the kind marketed under the trade mark "PLATILON". In use the user obtains some pneumatic support from the air (or other gas) sealed within the container 4, as well as support from the body 1.

The supporting unit shown in Figure 2 may be used as a palliasse and comprises a body 5 in the form of a flexible and resilient pad of polyester fibre, typically 50mm thick. The body 5 is sealed within a 35 container 6 similar to the container 4. ' v F? If desired, a mattress of compound form may be made by stacking or superimposing a unit of the kind shown in Figure 2 on top of a unit of the kind shown in Figure 1. In that case each of the units may be 5 considered as constituting a mattress-component. Straps or other securing means (not shown) may be employed to secure the units together.

The supporting unit shown in Figure 3 comprises a 10 body of compound form consisting of a layer 7 of resilient foam material similar to the body 1 and a pad 8 of polyester fibre similar to the body 5 superimposed on the layer 7. A sheet 9 of polyurethane film, similar to that from which the containers 4 and 6 15 are made, is interposed between the layer 7 and the pad 8 to provide a positive barrier between the layer and the pad. The compound body this formed is sealed within a container 10 similar to the containers 4 and 6.

In a modified kind of construction the container 4, 6 or 10, as the case may be, is replaced' by a sealed bag which still tends to afford some t-in pneumatic support for the user but is composite I form and of which the working surface, that is the upper 25 surface in each of these cases, is made of a film that is impermeable to liquid water but is permeable to water-vapour. At least part of the remainder of the bag is made from some different material or from more than one different materials.

In a further modified construction the container is formed with a few very small apertures so that it is no longer sealed and in use, or at least in prolonged use, affords little or no pneumatic support for the 35 user. At the same time, the access to the interior of the container is restricted enough to prevent the \}.2. FATEHT Of FICS 2 2 MAR 1394 239582 V ingress of perspiration, and dust etc. to an extent sufficient to enable bed-mites to colonise the body inside the container.

In a different type of modification the container is fully sealed but at least its working surface is made from a textile fabric provided with a coating which is impermeable to liquid water but is permeable to water-vapour, a suitable material being one marketed 10 under the trade mark "VENTFLEX" or"GORE-TEX".

It is to be understood that while the supporting units described above all constitute mattresses or other articles on which a user may lie down, supporting 15 units of other sizes and shapes but of similar constructions may be provided for other purposes such as for sitting on or reclining against, such units constituting pillows or cushions or being incorporated in seats, chairs or the like. Alternatively a 20 supporting unit in accordance with the invention may constitute only part of a mattress or the like. For example, a supporting unit may comprise a lower part of a mattress, that is a part in which the user's body rather than the user's head is intended to lie, the 25 user's head resting on some other form of supporting unit. Thus, the lower part of a cot-mattress for a baby may be in accordance with the present invention while the upper part of the mattress, on which the baby's head rests, may be afforded by a resilient body 30 which is formed with an array of through air-holes or is otherwise formed to reduce the likelihood of a baby having difficulty breathing when its face is applied directly to the resilient body.

Figure 4 shows an alternative embodiment incorporating a typical mattress construction 239582 n comprising a spring unit 11 supporting a number of layers of fillings and an outer covering 12. The layers of filling comprise a first layer of wool felt 13, a layer of resilient foam material 7 and a 5 layer of polyester fibres 5. The outer covering 12 comprises a layer of fabric ticking. The fabric ticking extends around and totally encloses the interior upholstery. The outer covering 12 comprises an upper panel 14, a lower panel 15 and side panels 16 10 joining the upper and lower panels.

The mattress is constructed such that lower and upper halves of the mattress comprise the same fillings. Accordingly below the spring unit 11 there 15 is provided a second lower layer 17 of wool felt and lower layers of resilient foam 71 and polyester fibres 51.

In the embodiment of Figure 4 a barrier to the 20 passage of infectious agents is provided in the form of a sheet 18, 19 of vapour permeable material encapsulating the first and second layers 13, 17 of wool felt. A side panel 20 of the vapour permeable material joins the sheets 18 and 19 such that the 25 spring unit 11 is contained within an integral barrier and each of the two wool felt layers 13, 17 are encapsulated within a barrier.

The sheets 18, 19 may be sealing joined -to the 30 panel 20 by heat sealing or other means ensuring an adequate barrier is maintained.

In a further embodiment shown in Figure 5 a sheet 21 of vapour permeable material is incorporated 35 in the quilting process below the layer 5 of polyester fibres. The sheet 21 may be secured to the layer 5 of 239582 12 polyester fibres and ticking 13 by the quilting process. If this is done the apertures created by the quilting needles are sealed by suitable means such as a spray coating of a vapour permeable substance. Alternatively the sheet 21 may be laminated to the layer of polyester fibres.

The sheet 21 is sealingly joined to side panels 22 which are also joined to a lower sheet 23 located between the lower layer 5 * of polyester fibres and the lower layer of wool felt 17.

The mattress illustrated in Figure 5 of the accompanying drawings is otherwise the same as that of 15 Figure 4 and corresponding reference numerals have been applied to corresponding parts.

Claims (20)

WHAT WE CLAIM IS: 13

1. A mattress or other supporting unit comprising a number of layers of filling, an outer covering, a barrier to the passage of infectious agents positioned adjacent to at least one of the layers within the outer covering, and a permanent non-removable sealed container enclosing at least some of the layers of filling, in which the barrier is defined by a portion of the container and comprises at least one layer of material forming an integral component part of the mattress, and at least a substantial portion of the said portion of the container is vapour permeable, that is impermeable to liquid water, but permeable to water-vapour.

2. A mattress or the supporting unit according to claim 1, in which the vapour permeable material comprises polyethylene film.

3. A mattress or other supporting unit according to claim 1, in which the vapour permeable material comprises a textile fabric provided with a coating that is impermeable to liquid water but permeable to water vapour.

4. A mattress or other supporting unit according to claim 1, in which the vapour permeable material comprises a textile fabric laminated by a binding process to a micro-porous material.

5. A mattress or other supporting unit as claimed in any one of claims 1-4, in which the mattress comprises a spring unit supporting at least one layer of filling, and a sheet of vapour permeable material defining a 23 irp 9 | LiibSI 14 wall of the container is incorporated in the mattress or unit construction.

6. A mattress or other supporting unit according to claim 5, in which the interior of the mattress or unit within the container is sealed off from the remainder of the mattress by the use of sealing means.

7. A mattress or other supporting unit according to claim 5 or claim 6, in which a layer of vapour permeable material is incorporated above and below the spring unit.

8. A mattress or other supporting unit according to claim 7 when dependant upon claim 6, in which sealing means is provided along each side of the spring unit to define a continuous side wall of the container interconnecting the two layers of vapour permeable material.

9. A mattress or other supporting unit according to claim 8, in which the sealing means comprises a panel of a vapour permeable or air tight material.

10. A mattress or other supporting unit according to claim 7 as dependant upon claim 6, in which the two layers are extended, and sealing means seal the peripheries of the two layers together,

11. A mattress or other supporting unit according to any one of claims 5-10, in which at least an upper layer of vapour permeable material is incorporated into layers of filling.

12. A mattress or other supporting unit according to claim 11, in which the upper layer of vapourjgermeable * 0 ? o ^ CI c 15 material is incorporated into the filling during the quilting process.

13. A mattress or other supporting unit according to claim 11, in which a number of layers are quilted together to form a quilted layer and, after the quilting process is complete, a layer of vapour permeable material is laminated to the underside of the quilted layer.

14. A mattress or other supporting unit according to claim 11, in which the upper layer of vapour permeable material is stretched over a layer of filling.

15. A mattress or other supporting unit according to claim 1, in which the container is fully closed so that in normal use the amount of air or other gas within it remains constant or alters only very slowly with the result that the supporting unit tends to provide at least some pneumatic support for a user of the unit.

16. A mattress or other supporting unit according to any one of the preceding claim, including a body consisting solely of a layer of resilient foam material.

17. A mattress or other supporting unit according to claim 16, in which at least one main face of the layer is of convoluted form.

18. A mattress or other supporting unit according to any one of claims 1-15, including a body consisting solely of a pad of fibrous material. o 16

19. A mattress or other supporting unit according to any of claims 1-15/ including a body of compound form comprising a layer of foam/ and a pad of fibrous material.

20. A mattress or other supporting unit according to claim 21/ in which the pad is closer to the barrier than the layer of foam, and a flexible diaphragm of a material similar to that of the barrier is disposed between the layer of foam and the pad. SLUMBERLAND PLC By their attorney; HENRY HUGHES /