Wound dressing with conformable elastomeric wound contact layer

• US 5,445,604 A
• Filed: 10/15/1993
• Issued: 08/29/1995
• Est. Priority Date: 02/13/1981
• Status: Expired due to Term

• Current Assignee: Smith and Nephew Associated Companies PLC (Smith & Nephew PLC)
• Original Assignee: Smith and Nephew Associated Companies PLC (Smith & Nephew PLC)
• Inventors: Lang, Stephen M.
• Primary Examiner(s): PREBILIC, PAUL B
• Application Number:
  US08/138,610
• Time in Patent Office: 683 Days
• Field of Search: 604/304, 604/307, 604/369, 604/389, 604/390.1, 604/396, 604/397, 424/443, 424/445, 424/447, 424/448, 602/47
• US Class Current: 602/47
• CPC Class Codes: A61F 13/01046 Air-vapor permeability
• CPC Class Codes: A61F 13/069 Decubitus ulcer bandages
• CPC Class Codes: A61F 13/08 Elastic stockings; for contracting aneurisms
• CPC Class Codes: A61F 13/51121 characterised by the material
• CPC Class Codes: A61F 13/512 characterised by its apertures, e.g. perforations
• CPC Class Codes: A61F 13/534 having an inhomogeneous composition through the thickness of the pad A61F13/538, A61F13/539 take precedence; homogeneous cores with tissue wrapping A61F13/53
• CPC Class Codes: A61F 13/539 characterised by the connection of the absorbent layers with each other or with the outer layers
• CPC Class Codes: A61F 13/8405 Additives, e.g. for odour, disinfectant or pH control
• CPC Class Codes: A61F 2013/00119 elastic
• CPC Class Codes: A61F 2013/00157 for burns or skin transplants A61F2013/00187 takes precedence; not adhering to the wound A61F2013/00217
• CPC Class Codes: A61F 2013/00217 not adhering to the wound
• CPC Class Codes: A61F 2013/00263 vapour permeability >500 g/m2/24h
• CPC Class Codes: A61F 2013/00519 for treating burn
• CPC Class Codes: A61F 2013/00697 elastomer-, e.g. rubber- based
• CPC Class Codes: A61F 2013/0074 containing foams
• CPC Class Codes: A61F 2013/00782 with macroscopic openings
• CPC Class Codes: A61F 2013/00876 vapour permeability >500 g/mg/24h
• CPC Class Codes: A61F 2013/0091 with disinfecting or anaesthetics means, e.g. anti-mycrobic
• CPC Class Codes: A61F 2013/15821 characterized by the apparatus for manufacturing
• CPC Class Codes: A61F 2013/530802 characterized by the foam or sponge other than superabsorbent A61F2013/530649 takes precedence
• CPC Class Codes: A61F 2013/53445 : from several sheets
• CPC Class Codes: A61F 2013/5395 : with thermoplastic agent, i.e. softened by heat
• CPC Class Codes: A61K 2300/00 : Mixtures or combinations of active ingredients, wherein at least one active ingredient is fully defined in groups A61K31/00 - A61K41/00
• CPC Class Codes: A61K 31/19 : Carboxylic acids, e.g. valproic acid salicylic acid A61K31/60
• CPC Class Codes: A61K 31/485 : Morphinan derivatives, e.g. morphine, codeine
• CPC Class Codes: A61K 31/52 : Purines, e.g. adenine
• CPC Class Codes: A61K 31/57 : substituted in position 17 beta by a chain of two carbon atoms, e.g. pregnane or progesterone
• CPC Class Codes: A61L 15/26 : Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof A61L15/225 takes precedence
• CPC Class Codes: A61L 15/42 : Use of materials characterised by their function or physical properties liquid bandages A61L26/00
• CPC Class Codes: A61L 15/425 : Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 15/46 : Deodorants or malodour counteractants, e.g. to inhibit the formation of ammonia or bacteria
• CPC Class Codes: A61L 2300/404 : Biocides, antimicrobial agents, antiseptic agents
• CPC Class Codes: C08L 75/04 : Polyurethanes

Abstract

Low adherency wound dressings which comprise a wound facing layer, an intermediate absorbent layer and an outer layer characterized in that the wound facing layer comprises a conformable elastomeric apertured film, the intermediate absorbent layer comprises a conformable hydrophilic foam and the outer layer comprises a continuous moisture vapor transmitting conformable film; materials therefor and processes for the manufacture thereof are described.

Claims

1. A conformable low adherency wound dressing which comprises

(a) a low adherency wound facing layer 0.05 to 2.5 mm thick which is a conformable elastomeric apertured net;

(b) an absorbent layer comprising a conformable hydrophilic foam 0.5 to 20 mm thick; and

(c) a continuous conformable moisture vapour permeable outer film layer which acts as a bacterial barrier and has a moisture vapour transmission rate of from 300 to 5000 grams/square meter/24 hours at 37°

C. at 100% to 10% relative humidity difference, said wound facing layer and said outer layer being laminated to opposing faces of said absorbent layer over the operative area of the dressing.

2. A dressing according to claim 1, in which the conformable elastomeric net comprises an integral net.

3. A dressing according to claim 1, in which the conformable elastomeric net has 4 to 40 apertures per cm.

4. A dressing according to claim 1, in which the conformable elastomeric net comprises a polyurethane.

5. A dressing according to claim 1, in which the continuous conformable layer has a moisture vapour transmission rate of 500 to 2000 grams/square meter/24 hours at 37°

C. at 100% to 10% relative humidity difference.

6. A dressing according to claim 1, in which the continuous moisture vapour transmitting conformable film layer comprises a polyurethane.

7. A dressing according to claim 1, in which the conformable outer film layer comprises a moisture vapour transmitting adhesive layer.

8. A dressing according to claim 1, in which the conformable hydrophilic foam is a foam of hydrophilic polymer.

9. A dressing according to claim 8, in which the hydrophilic polymer is hydrophilic polyurethane.

10. A dressing according to claim 1, in which the hydrophilic foam comprises an open cell foam with a cell size of 50 to 500 microns.

11. A dressing according to claim 1, in which the hydrophilic foam comprises an open cell foam in which 30% to 60% of the total area of the cells are membrane openings.

12. A sterile dressing according to claim 1, within a bacteria impervious package.