NZ732625B2 - Wound dressing - Google Patents

Abstract

The invention provides a wound dressing for actively assisting with the healing process of a wound by absorbing body fluid and keeping it away from the wound bed to help prevent maceration and over granulation, which includes a 1 to 12 mm thick layer of absorbent non-woven fibre material between 150 and 1200 grams per square meter, which layer includes a mixture of viscose fibres and polyester fibres which more viscose than polyester, and of which the fines of the viscose is between 1,5 and 3 dtex and the fines of the polyester is between 2 and 3 dtex, and between 7 and 25 % chitin fibres mixed or interwoven with the viscose and polyester fibres with the chitin fibres having a linear density between 1.5 and 2.5 dtex. and 1200 grams per square meter, which layer includes a mixture of viscose fibres and polyester fibres which more viscose than polyester, and of which the fines of the viscose is between 1,5 and 3 dtex and the fines of the polyester is between 2 and 3 dtex, and between 7 and 25 % chitin fibres mixed or interwoven with the viscose and polyester fibres with the chitin fibres having a linear density between 1.5 and 2.5 dtex.

Description

(12) Granted patent specificaon (19) NZ (11) 732625 (13) B2 (47) Publicaon date: 2021.12.24 (54) WOUND DRESSING (51) Internaonal Patent Classificaon(s): A61F 13/15 (22) Filing date: (73) Owner(s): 2015.11.24 MOUTON, Jacobus, Frederick MOUTON, Hendrika (23) Complete specificaon filing date: MOUTON, Arnold 2015.11.24 MARX, Shawn (30) Internaonal Priority Data: (74) Contact: GB 1420862.3 2014.11.24 JAMES & WELLS (86) Internaonal Applicaon No.: (72) or(s): MOUTON, Jacobus, Frederick (87) Internaonal Publicaon number: WO/2016/086243 (57) Abstract: The invenon es a wound dressing for acvely assisng with the healing s of a wound by absorbing body fluid and keeping it away from the wound bed to help prevent maceraon and over granulaon, which includes a 1 to 12 mm thick layer of absorbent ven fibre material n 150 and 1200 grams per square meter, which layer includes a mixture of viscose fibres and polyester fibres which more viscose than polyester, and of which the fines of the viscose is between 1,5 and 3 dtex and the fines of the polyester is between 2 and 3 dtex, and n 7 and % chin fibres mixed or interwoven with the viscose and polyester fibres with the chin fibres having a linear density between 1.5 and 2.5 dtex.

NZ 732625 B2 Title: Wound Dressing Technical field of the invention This invention relates to wound dressings.

Background to the invention The inventor is aware of the need for a wound dressing, which not only cover and protect the wound but create a healthy wound bed that is well vascularised. The reconstruction of the wound bed is of utmost importance. By this the inventor means to remove barriers and ctions that prevent or delays wound healing. g is optimized if the wound bed is healthy. It is therefore an object of the invention to e a dressing which assists the body with the healing process, by preparing the wound bed for healing. An absorbent dressing is very important to absorb body fluid and keep it away from the wound bed, preventing maceration and over granulation.

Breaking down of slough and necrotic tissue improves wound healing, but also increases the volumes of exudates. This must be monitored carefully to prevent damage to y skin. Preferably, the dressing materials should also assist with the draining of oedem from the wound bed which reduces swelling and improves blood supply to the wound bed.

It is an object of the invention to provide a highly absorbent wound dressing, which actively s with the healing process of a wound, in use.

General description of the invention According to the invention there is provided a wound dressing, which es a 1 to 12 mm thick layer of absorbent ven fibre material of between 150 and 1200 grams per square meter, which layer includes a mixture of viscose fibres and polyester fibres with more viscose than ter, and of which the linear density of the viscose is between 1.5 and 3 decitex (dtex) and the linear density of the polyester is between 2 and 3 dtex. Dtex is grams per ,000 meters of fibre.

The layer of absorbent non-woven fibre material may comprise two or more thinner layers of absorbent non-woven al needle punched together to form the single layer.

The absorbent layer may preferably also include between 7 and 25 % chitin fibres mixed or intenNoven with the e and polyester fibres with the chitin fibres having a linear density between 1.5 and 2.5 dtex.

One or both sides of the layer of absorbent material may be covered by a non-adherent layer. The non-adherent layer or layers may be heat bonded / laminated to the absorbent layer. The non-adherent layer may be a thin film of polyurethane or a HDPE based material such as CM18 produced by Smith & Nephew.

The composite y may be between 150 and 1200 grams per square meter (gsm), preferably about 700 - 750 gsm.

The polyester fibre length may be n about 30 and 70mm, preferably about 50mm.

The viscose fibre length may be between about 20 and 60mm, preferably about 40mm.

The chitin fibre length may be between about 30 and 70mm, preferably about 60mm.

WO 86243 In the case where two layers are needle punched together to form one layer, the punching density may be between 250 and to 380 punches per square centimetre, preferably about 320.

The construction of the ng makes the material “super ent” with a “pass — on” effect from one dressing to another. The composition of the dressing also secures the exudates inside the dressing without “fall back” or “dripping” of exudates back onto the wound bed. This prevents the ng of healthy surrounding skin. This dressing helps to reduce swelling and the restoration of the bacterial balance in the deeper compartments of the wound bed. This “pass — on” effect prevents colonization and duplication of bacteria.

The antimicrobial fiber that forms part of the composition is very important in controlling bacterial levels on the wound bed, which helps to keep the wound bed healthy.

Some embodiments of the dressing also has a non-adherent film layer that help to protect the healthy wound bed. This film ng is suitable on all type of wounds especially burns. Superficial healthy wounds with low volumes of exudates may be dressed with the film layer dressing. The film layer does not interfere with the healing process but rather protects the wound bed from any adherence by the dressing. New ation tissue will not be harmed or damaged. The film may preferably breathable and of HDPE or polyurethane.

Detailed description of the invention The invention is now described by way of examples.

Examples 1 and 2, with about 10x by weight absorbency capacity, in accordance with the invention, is a wound dressing, which includes a i 3 - 5 mm thick layer of ent non-woven fibre material of i 700 - 750 grams per square meter, which layer includes a mixture of 70% viscose fibres and 30% polyester fibres. t ecification: e 1 Example 2 WmFiber Len-thigé/éiéfirtfi}? Len-thfléfififiéw densit ifigfigw‘i Viscose Linear density 1.67dtex Chitin Fiber Lenoth 5:} 60mm densH 70% Viscose 60% Viscose % ter 30% ter % Chitin Densit WE'E‘JE Souare Meterifi‘afifi Thicknessifi‘afiwgifi Example 3, with about 10x by weight absorbency capacity, according to the invention there is provided a wound dressing, which includes the absorbent layer of the wound dressing described in Examples 1 and 2, which includes a non-adherent layer on both sides of the layer of absorbent material. The non- adherent layers are heat bonded / laminated to the absorbent layer.

Example 4 includes two absorbent layers which are needle punched together to form one thick absorbent layer as described in Examples 1 and 2.

Example 5 includes the absorbent layer as described in Example 4, which es a non-adherent layer on both sides of the layer of absorbent material.

The non-adherent layers are heat bonded / laminated to the absorbent layer.

Examples 6 to 9 is similar to and corresponds with examples 1 to 4 wherein the viscose is 55%, the polyester is 35% and includes 10% chitin fibres.

Further examples include a wound dressing similar to examples 1 to 9 with the single layer being 200gsm and about 1 mm thick or being 600gsm and 1O about 3mm thick.

The applicant has found that the wound dressing absorbs fluids about 10x its own weight by means of adhesion and cohesion forces as well as electrostatic forces to draw out of the wound solid wound material and fluids vertically and to spread it horizontally in the absorbent layer. The wound material includes harmful bacteria. The wound dressing ly and uously removes unwanted material from the wound until absorbent ty is reached keeping the wound clear allowing the wound to heal faster than without the wound dressing. In addition, the chitin fibres also e an antimicrobial function.

It shall be understood that the examples are provided for illustrating the invention further and to assist a person skilled in the art with understanding the invention and are not meant to be ued as unduly limiting the able scope of the invention.

Claims (9)

1. A wound dressing, which includes a 1 to 12 mm thick layer of ent non-woven fibre material of n 150 and 1200 grams per square meter, which absorbent ven fibre material includes: a mixture of viscose fibres and polyester fibres with more viscose than polyester, and of which the linear density of the viscose is between 1.5 and 3 dtex and the linear density of the polyester is between 2 and 3 dtex; and between 7 and 25 % chitin fibres mixed or interwoven with the e and polyester fibres with the chitin fibres having a linear density between 1.5 and 2.5 dtex.

2. A wound dressing as claimed in Claim 1, wherein the layer of absorbent non-woven fibre material comprises two or more thinner layers of absorbent non-woven material needle punched together to form the layer.

3. A wound dressing as claimed in claim 1 or claim 2, wherein one or both sides of the layer of absorbent material are covered by a non-adherent layer.

4. A wound dressing as claimed in Claim 3, wherein the herent layer or layers are each heat bonded / laminated to the absorbent layer.

5. A wound dressing as claimed in Claim 4, wherein the non-adherent layer or layers are selected from a thin polyurethane or HDPE film.

6. A wound dressing as d in any one of claims 1 to 5, wherein its composite density is between 150 and 1000 grams per square meter.

7. A wound dressing as claimed in any one of claims 1 to 6, wherein the polyester fibre length is between about 30 and 70mm.

8. A wound ng as claimed in any one of claims 1 to 7, wherein the viscose fibre length is between about 20 and 60mm.

9. A wound dressing as claimed in any one of claims 3 to 8, n the chitin fibre length is between 30 and 70mm.