GB2055581A

GB2055581A - Dressing

Info

Publication number: GB2055581A
Application number: GB8023027A
Authority: GB
Original assignee: PROFESSIONAL NURSING CARE Pty
Current assignee: PROFESSIONAL NURSING CARE Pty
Priority date: 1979-07-23
Filing date: 1980-07-15
Publication date: 1981-03-11
Also published as: AU6060880A

Abstract

A product, especially used as a wound dressing, comprises an absorbent mat having a polymeric material applied on at least one surface in a discontinuous layer, such that the surface is rendered non-adherent to skin or tissue and remains absorbent to body and other fluids. Preferably, an absorbent mat 20 has particles 24 of polymer powder (especially polypropylene) distributed on its surface, and then the mat is heated to cause the polymer to soften and spread over the surface to form agglomerates 26. <IMAGE>

Description

SPECIFICATION Dressing This invention relates to an absorbent material useful medically as a dressing. However it will be appreciated that the invention has wider significance in other fields.

Non-adherent dressings for wounds have been proposed comprising a semi-permeable membrane, normally consisting of a continuous plastic film formed with a plurality of perforations, laminated to an absorbent backing. The dressing is applied to the wound with the membrane adjacent the skin, the perforations being large to encourage drainage of the exudate away from the wound site. However, one of the disadvantages of the prior art of dressings is that the plastic film does not allow sufficient wicking of the exudate away from the wound with concomitant disconfort and poor healing conditions.

It is an object of the present invention to provide an improved absorbent and non-adherent dressing for wounds.

According to the invention a product comprises an absorbent mat having a polymeric material applied in a discontinuous layer on at least one surface thereto such that the surface is rendered nonadherent to animal or human skin, tissue or the like and yet remains adsorbent to body and other fluids.

The material is preferably a non-woven fabric according further to the invention the treated surface of the product is perforated to provide ventilation of a wound.

The arrangement is such that the absorbent fibres of the absorbent material are in such close proximity to the treated surface that any fluids deposited on the surface are wicked through the surface.

The polymeric material may exist as agglomerates on the surface of the mat or may exist as a coating of individual fibres or groups of fibres on the surface of the mat. Spaces between the coated fibres serve to permit the fluids to come into contact with noncoated fibres adjacent the coated surface fibres.

As plastic substances useful in the present invention, polypropylene is preferred, but it will be appreciated that many other polymers may be used in the practice of the invention. It will also be appreciated that the degree of permeability of the surface of the product of the invention may be varied by the amount of polymer used per unit of area or by the method of application.

In a preferred form of the invention, particles of polymer are applied to the surface of the mat, and the mat is then heated to cause the polymer to soften and spread over the surface to impart the desired non-adherent yet absorbent characteristics as well as the permeability required.

Two embodiments of the invention are described with reference to the accompanying drawings in which:~ Figure 1 is a perspective view of a dressing according to the invention, and Figure 2 and 3 are cross-sectional views of mat showing the stages in the preparation of the dressing in one example thereof.

In Figure 1 a mat 10 of fibrous non-woven material is provided, the surface 12 of which has applied thereto, a thin discontinuous coating of a thermoplastic polymeric material in an amount just sufficient to coat surface fibres but leaving sufficient space therebetween to permit passage of body fluids to the fibres therebelow.

Perforations 14 are provided for ventilation of the wound.

In Figures 2 and 3 an absorbent sheet material backing 20 comprises a random-laid fibre blend. For a non-adherent dressing both cotton/rayon and polyester/cotton blends have been found most suitable although it will be appreciated that the choice of fibre blends is in practice limited only by the envisaged use of the end product. The short staple fibres 22 are not woven but merely laid together to the thickness of the backing desired.

The absorbency of the backing 20 depends partly on the density of the lay-up of the fibres 22 and partly on the choice of fibre. Both these factors can therefore be varied to suit the purpose for which the dressing is intended.

On the absorbent backing 20 particles 24 distilled polypropylene powder are distributed. The particle size of the powder should be of the order of 300 microns or less, and the amount used should be about 30 g/m2. Obviously the correct amount can be determined by simple trial and error.

The backing 20 with the powder on is then heated to about 1600C until the polypropylene sinters. The granules 24 of polypropylene sinter into agglomerates 26 which in turn flow into the gaps between the fibres 22. As the fabric cools the polypropylene sets and fuses with the backing 20.

Because of the tendency of the granules to sinter the resultant polypropylene layer formed on the backing is discontinuous with voids between the clumps 26. In preliminary tests, a dressing with a coating ratio of 70 percent void to 30 percent polypropylene has given the best results.

It should be borne in mind that, while the invention has been described with reference to a nonadherent dressing it is not limited thereto, in fact the applications thereof are virtually unlimited.

The most convenient form of heating is by way of passing the sheet through heated rollers.

Although polypropylene is preferred because of its resistance to autoclaving, other polymers may be used. For example, if the dressings are merely to be sterilised with gamma rays or gas, polyethylene may conveniently be used.

The backing may be the well-known fusible inter linings for garments.

Claims

1. A product comprising an absorbent mat hav ing a polymeric material applied in a discontinuous layer on at least one surface thereto such that the surface is rendered non-adherent to animal or human skin, tissue or the like and yet remains absorbentto body and other fluids.

2. A product as claimed to claim 1 in which the mat comprises a sheet of non-woven fabric material.

3. A product as claimed in claim 1 or claim 2 in wnich the polymeric material is in the form of agglomerates deposited on the surface of the mat leaving areas of the surface untreated with the material such that fluids deposited on the agglomerates are wicked to the untreated areas of the mat.

4. A product as claimed in any one of claims 1 to 3 in which the polymeric material is applied to the mat in the form of polymer particles and the mat is thereafter heat treated to cause the polymerto soften and spread over the surface of the mat.

5. A product as claimed in claim 1 or claim 2 in which the individual fibres or groups of the fibres appearing on the surface of the mat are coated with the polymeric material and the noncoated fibres form the absorbent areas of the mat.

6. A product as claimed in any one of claims 1 to 5 in which is provided with perforations to allow for ventilation.

7. A product as claimed in any one of claims 1 to 6 in which the polymeric material is polypropylene.

8. A wound dressing manufactured from a product according to any one of claims 1 to 7.

9. A product substantially as herein described with reference to any of Figures 1, 2 or 3 of the accompanying drawings.