NZ335930A - Method for constructing upholstory and bedding for controlling dust mites and products therefor - Google Patents

Abstract

A method of constructing an upholstery or bedding item 2 or 12 which is substantially free of dust mites throughout the life of the item includes the following steps: (a) provide a polyester filling material 3 or 13 which is impregnated with a compound selected from the group: a water absorbent or adsorbent compound, an antimicrobial compound; an anti-fungal compound; and a combination of these; (b) encase the filling in a mite-proof fabric; and (c) then shape the filling and fabric to the predetermined shape of the item, to complete the manufacture of the filled item.

Description

1 PATENTS FORM NO. 5 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No: 335930 Dated: 25 May 1999 James & Wells Ref: 40825 Method for Controlling Dust Mites and Product Therefor We, Ellis Fibre Ltd, of 152 Kaikorai Valley Road, Dunedin, New Zealand, a New Zealand company 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: ^ellectual Property Office of NZ 1 s m :::o Received Technical Field The present invention relates to a method of construction of upholstery or bedding items for substantially reducing the proliferation of dust mites.

Background Art A large proportion of the population suffer from allergic reaction to dust mites and their by-products, or suffer from asthma as a result of these. The mites live in the stuffing inside mattresses, pillows, duvets and the like, and in other upholstery.

Mite allergen levels can be reduced to very low levels when three levels of intervention are used. For example: hot water washing of bedding; encasing mattresses and pillows in plastic or other mite-impermeable material; and removing carpets from bedrooms or other areas.

However, much of this activity camiot be done with general furniture. Also, many of the means of encasing mattresses and pillows (etc) have undesirable side effects. For example, impermeable plastics can cause safety problems or other water retention problems within the furniture.

There have been a number of inventions which address aspects of the dust mite problem. For example, there are various methods for treating the surface of a material with a chemical for killing dust mites on the surface. Examples of this can be found in US Patent No. 5672362 (Burnett). This discloses the use of a 5 % di-sodium octaborate tetrahydrate solution which is applied to the surface of carpets or bedding with a hot water vacuum. US Patent No. 5271947 (Miller) uses a finely divided salt in contact with the substrates in the bedding.

The question of dust mites passing into the bedding to begin with and the question of permeability to fluids of the covers on upholstery are addressed to some extent by US Patent No. 5050256 (Woodcock). This patent discloses bedding in which substantially all of the upholstery (or item) is enclosed in a material barrier which is substantially impermeable to mites. This is a micro-porous barrier which is air permeable. It is also possible that such a material could be permeable to vapour or water.

However, the use of such materials in covers on upholstery (or in bedding items) to reduce mites does have drawbacks. As disclosed in Woodcock, considerable attention has to paid to the manner of stitching and seams on the material. Woodcock discloses the use of closely meshed sliding fasteners and the need to use either special types of stitching which leave little or no perforations, or to add additional sealing means such as coating with polyurethane. Further, the thin coatings of impermeable material can crack and become permeable with age, or have their effectiveness reduced through cracking or removal by repeated washing of the item or cover.

However, there are some upholstery finishes where regular quilting or surface stitching provides means of holding the filling in place as well an aesthetically pleasing finish. The solutions proposed by Woodcock for stitch holes detract from the finish and appearance of a quilt.

Once access is permitted to the inside for the mites, the mite-impermeable barrier then has the reverse effect from that intended, as it allows water and other items to pass through to the mites, but the mites cannot easily get out and the inside of the pillow or item becomes full of mites.

It is possible that slip covers can be placed over the top of such special mite barrier fabrics as a further, protective layer. However, the area between the inside of the slip cover and the surface of the mite barrier becomes a breeding ground for mites and the problem is not averted as the mites are close to the surface of the upholstery or item.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

Disclosure of Invention According to one aspect of the present invention, there is provided a method of constructing an upholstery or bedding item which is substantially free of dust mites throughout the life of the item of upholstery, said method including the following steps: (a) providing a polyester filling material which is impregnated with a compound selected from the group: a water absorbent or adsorbent compound, an antimicrobial compound; an anti-fungal compound; and a combination of these; (b) encasing said filling in a mite-proof fabric; and (c) shaping the filling and fabric to the predetermined shape of the item and completing the manufacture of the filled item.

Preferably, said filling is a commercially available polyester filling to which the compound is permanently chemically bonded by a known process. Preferably the compound is zeolite, or includes zeolite. Also, preferably, the zeolite can be either natural or synthetic.

The mite-proof fabric may be either woven or bonded, depending on selection options. Preferably, the fabric incorporates a permeable membrane that is both air permeable and vapour permeable.

The above method acts as a double barrier to the penetration of dust mites into the item, as any mites that enter through any defects in the permeable membrane or the manner of stitching of the item will die as the zeolite absorbs any water vapour present; thus providing an alien environment to the sustaining of life of any mites.

The above method can optionally include a step (d) of freezing the item to below 0°C, for up to 24 hours or for sufficient time to kill any mites which may be caught up in the item in assembly. This step provides a good alternative to requiring that such items be assembled under axenic conditions, which would otherwise make such items extremely expensive to produce.

The above item (when a woven fabric is selected) is capable of being washed to a temperature of 60°. This allows for continued use of the item without any reduction in the efficacy of the mite reduction incorporated in the manufacture.

According to another aspect of the present invention, there is provided an item of upholstery which is manufactured substantially by the method as described above.

Preferably the item is one selected from the range: pillow, mattress, mattress cover, blanket, quilt, continental quilt, duvets, other bedding items, upholstery slip covers, cushions and frame, and upholstered furniture.

Brief Description of drawings Further aspects of the present invention will become apparent from the following description which is given by way of example only, and with reference to the construction of a pillow and to the accompanying drawings, in which: Figure 1 is a diagrammatic cross-section through a pillow made in accordance with the method of the present invention; and Figure 2 is a diagrammatic cross-section of a duvet made in accordance with the method of the present invention. best modes for carrying out the invention Figure 1 shows a pillow 2 in cross section, the pillow 2 being made in accordance with the present invention. The pillow 2 is filled with a polyester filling 3 and covered by a pillow cover 4. The pillow 2 is shown with a pillow slip 5 over the top of the cover 4 with filling 3.

The filling 3 is a polyester filling of a type that is commercially available. Such filling 3 includes a chemically bonded zeolite, bonded to the polyester. This bonding process is carried out in known manner.

The cover 4 can be woven or non-woven, as is desired. A woven nylon or polyester fabric of the cover 4 is impermeable to mites (having micro-porous holes of generally less than 10 microns). Such woven or non-woven fabric can be air and vapour permeable, thus avoiding the problem of water build-up on the surface of the pillow 2. The cover 4 can be stitched at seams 6 in known manner and by standard means.

The slip 5 can be an optional, additional slip covering the cover 4, or may be a commercially available pillow slip 5, as is desired. The cover 4 will generally prevent mites entering the pillow 2. However some mites may be present in the construction of the pillow 2 or may enter through flaws in the fabric and/or holes in the seams 6. The filling 3, with the bonded zeolite, absorbs or adsorbs (depending on the manner of attraction) any water vapour present in the pillow 2. Thus any mites present in the filling 3 will not be able to live in the absence of water vapour or water.

Should the pillow 2 require washing or cleaning (for example as a result of general wear and tear), such pillow 2 can be washed in water of a temperature of approximately 55°C, or higher, without loss of function of the filling 3 or the cover 4.

As no special water resistant seaming 6 need to be added to the pillow 2, such continued washing will not detract from the efficacy of either the woven fabric cover 4 or the filling 3.

Referring to figure 3, a duvet 12 made in accordance with the method of the present invention, is shown with a cover 14 and filling 13. The duvet 12 includes a number of quilting seams 16 and a slip cover 15. The duvet 12 may be constructed by filling a loose cover 14 with the filling material 13. The seams 16 on the outside and quilting seams 16 may be added in known manner, in any shape as is desired. The slip cover 15 may encase the cover 14 of finished duvet 12. Optionally the slip cover 15 may be the finished in an aesthetically pleasing pattern or a further cover may be added (not shown), as is desired.

It will be appreciated that, with assembly and construction of the pillow 2 and duvet 12, in standard factory conditions, that the filling 3 and interior of the pillow 2 or duvet 12 may not be perfectly free of mites. The pillow 2 and duvet 12 can be rendered free of mites by freezing the item for up to 24 hours at temperatures below 0°C. Such freezing can, for example, be carried out in a refrigerated container, by stacking the container full and leaving the items (2,12) for up to 24 hours or more.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof. 8

Claims (12)

WHAT WE CLAIM IS:

1. A method of constructing an upholstery or bedding item which is substantially free of dust mites throughout the life of the item, said method including the following steps: (a) providing a polyester filling material which is impregnated with a compound selected from the group: a water absorbent or adsorbent compound, an antimicrobial compound; an anti-fungal compound; and a combination of these; (b) encasing said filling in a mite-proof fabric; and (c) shaping the filling and fabric to the predetermined shape of the item and completing the manufacture of the filled item.

2. A method of constructing an upholstery or bedding item as claimed in claim 1 wherein said filling is a commercially available polyester filling to which the compound is permanently chemically bonded.

3. A method of constructing an upholstery or bedding item as claimed in either claim 1 or claim 2 wherein the compound is natural or synthetic zeolite.

4. A method of constructing an upholstery or bedding item as claimed in either claim 1 or claim 2 wherein the compound includes natural or synthetic zeolite.

5. A method of constructing an upholstery or bedding item as claimed in any one of claims 1 to 4 wherein the mite-proof fabric is either woven or bonded.

6. A method of constructing an upholstery or bedding item as claimed in any one of claims 1 to 5 wherein the mite-proof fabric incorporates a permeable membrane that is both air permeable and vapour permeable.

7. A method of constructing an upholstery or bedding item as claimed in any one 9 of claims 1 to 6 wherein the method includes a step (d) of freezing the item to below 0°C, for up to 24 hours or for sufficient time to kill any mites which may be caught up in the item in assembly.

8. A method of constructing an upholstery or bedding item as claimed in any one of claims 1 to 6 wherein the item is assembled under axenic conditions.

9. A method of constructing an upholstery or bedding item as claimed in any one of claims 1 to 8 wherein the item is one selected from the range: pillow, mattress, mattress cover, blanket, quilt, continental quilt, duvets, other bedding items, upholstery slip covers, cushions and frame, and upholstered furniture.

10. A method of constructing an upholstery or bedding item as described herein with reference to the accompanying drawings.

11. An item of upholstery or bedding which is manufactured by the method as claimed in any one of claims 1 to 10.

12. An item of upholstery or bedding which is manufactured by the method described herein with reference to the accompanying drawings. ELLIS FIBRE LIMITED by their Attorneys JAMES S. per: Intellectual Property Office of NZ 16 MAY 2000 RECEIVED