WOUND DRESSING WITH CONTROLLABLE PERMEABILITY

• US 20080167594A1
• Filed: 01/10/2008
• Published: 07/10/2008
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Nuvesse Skin Therapies Inc.
• Original Assignee: Polyremedy, Inc.
• Inventors: SINIAGUINE, Oleg
• Granted Patent: US 8,237,007 B2
• Time in Patent Office: Days
• US Class Current: 602/48
• CPC Class Codes: A61F 13/00063 comprising medicaments or additives, e.g. odor control, PH control, debriding, antimicrobic drug delivery dressings A61K9/70; chemical aspect of the additives A61L15/00
• CPC Class Codes: A61F 13/00995 for mechanical treatments
• CPC Class Codes: A61F 13/01021 characterised by the structure of the dressing
• CPC Class Codes: A61F 2013/00255 with pores
• CPC Class Codes: A61F 2013/00604 Multilayer
• CPC Class Codes: A61F 2013/00863 with pores
• CPC Class Codes: A61F 2013/0091 with disinfecting or anaesthetics means, e.g. anti-mycrobic

Abstract

Wound dressings and methods of manufacturing wound dressings are provided. The wound dressings include portions that are converted from a moisture vapor permeable material to a material having reduced moisture vapor permeability. The conversion may be accomplished in a variety of ways. In some embodiments, a solvent is used to dissolve a porous material to thereby form a non-porous film. In other embodiments, heat is applied to melt a porous material to thereby form a non-porous film. The heat may be applied using a heated gas or a heating element to directly or indirectly heat the material.

Claims

1. A method of fabricating a wound dressing comprising a wound facing surface and an exterior surface opposite the wound facing surface, said method comprising:

providing a first sheet comprising a moisture vapor permeable material; and

converting a portion of the first sheet to reduce the moisture vapor permeability of the portion of the first sheet.

2. The method of claim 1, wherein said first sheet comprises a microfiber material.

3. The method of claim 1, wherein said converting the portion of the first sheet comprises applying a solvent to the portion of the first sheet to dissolve the portion of the first sheet.

4. The method of claim 1, wherein said converting the portion of the first sheet comprises applying heat to the portion of the first sheet to melt the portion of the first sheet.

5. The method of claim 4, wherein said applying heat to the portion of the first sheet comprises directing heated air onto the portion of the first sheet.

6. The method of claim 4, wherein said applying heat to the portion of the first sheet comprises applying a heating element to the dressing.

7. The method of claim 4, further comprising:

positioning a second sheet adjacent to the first sheet;

wherein said melted portion of the first sheet bonds the first sheet to the second sheet.

8. A method of fabricating a wound dressing, comprising:

positioning a first sheet adjacent to a second sheet, the second sheet comprising a first layer and a second layer, wherein the first layer is moisture vapor permeable and the second layer has a lower melting point than the first layer; and

bonding the first sheet to the second sheet by heating the second layer of the second sheet to a temperature higher than the melting point of the second layer and lower than the melting point of the first layer so as to melt a portion of the second layer of the second sheet and bond the second layer of the second sheet to the first layer.

9. The method of claim 8, wherein:

the first sheet, the first layer of the second sheet, and an unmelted portion of the second layer of the second sheet are moisture vapor permeable; and

the melted portion of the second layer of the second sheet is less moisture vapor permeable than the unmelted portion of the second layer.

10. The method of claim 8, wherein:

prior to positioning the first sheet adjacent to the second sheet, converting a portion of the second layer of the second sheet to a film by heating a surface of the second layer of the second sheet to at least the melting point of the second layer of the second sheet.

11. The method of claim 8, wherein:

said heating the second layer of the second sheet comprises directing a heated gas onto the second layer of the second sheet.

12. The method of claim 8, wherein:

said heating the second layer of the second sheet comprises applying a heating element to either the first sheet or the second sheet.

13. A wound dressing comprising a wound facing surface and an exterior surface opposite the wound facing surface, said wound dressing comprising:

a first layer having a moisture vapor permeable region and a reduced moisture vapor permeable region;

p1 wherein said moisture vapor permeable region is made of a porous or fibrous material, and said reduced moisture vapor permeable region is made of a film.

14. The wound dressing of claim 13, wherein:

the moisture vapor permeable region and the reduced moisture vapor permeable region comprise the same chemical substance.

15. The wound dressing of claim 13, further

a second layer adjacent the first layer, said second layer having a higher melting point than the first layer.

16. The wound dressing of claim 13, further comprising:

a third layer provided between the first layer and the second layer, said third layer having a higher melting point than the first layer and a larger average pore size than the second layer.

17. The wound dressing of claim 13, further comprising:

a second layer positioned adjacent to the first layer, said second layer comprising a material insoluble in the first solvent.

18. The wound dressing of claim 17, wherein:

the first layer comprises a first microfiber type and a second microfiber type, said first microfiber type being soluble in the first solvent and the second microfiber type being insoluble in the first solvent.

19. The wound dressing of claim 17, further comprising:

a third layer positioned adjacent to the first layer, said third layer comprising a material insoluble in the first solvent.

20. The wound dressing of claim 19, wherein:

the third layer comprises at least partially hydrophobic polymer microfibers.

21. The wound dressing of claim 19, wherein:

the first layer, the second layer, or the third layer includes a substance enhancing wound healing.

22. The wound dressing of claim 19, wherein:

the first layer, the second layer, or the third layer includes a pharmacological substance.

23. The wound dressing of claim 17, wherein:

the first layer comprises at least partially hydrophobic polymer microfibers.

24. The wound dressing of claim 17, wherein:

the second layer comprises at least partially hydrophobic polymer microfibers.

25. The wound dressing of claim 17, wherein:

the first layer or the second layer has bacteriostatic, bactericidal, or antifungal properties.

26. A dressing, comprising:

a first sheet, said first sheet being moisture vapor permeable; and

a second sheet comprising a first layer and a second layer, wherein the first layer is moisture vapor permeable and the second layer has a lower melting point than the first layer;

wherein the second layer of the first sheet is bonded to the second sheet.

27. The dressing of claim 26, wherein:

a portion of the second layer of the second sheet comprises a film which is less moisture vapor permeable than the first sheet.

28. The dressing of claim 26, wherein:

a lateral dimension of the second sheet is larger than a lateral dimension of the first sheet.

29. The dressing of claim 26, wherein:

the first sheet comprises a first layer and a second layer, wherein the second layer of the first sheet has a lower melting point than the first layer of the first sheet and is bonded to the second layer of the second sheet.

30. The dressing of claim 29, further comprising:

a third sheet comprising a first layer and a second layer, wherein the second layer of the third sheet has a lower melting point than the first layer of the third sheet and is bonded to the first layer of the first sheet.

31. The dressing of claim 30, wherein:

a lateral dimension of the third sheet is larger than a lateral dimension of the first sheet.

32. The dressing of claim 30, wherein:

a lateral dimension of the second sheet is larger than a lateral dimension of the first sheet and a lateral dimension of the third sheet.