WOUND DRESSINGS, AND YARN USEFUL THEREIN

• US 20140309574A1
• Filed: 11/01/2012
• Published: 10/16/2014
• Est. Priority Date: 11/01/2011
• Status: Abandoned Application

• Current Assignee: Brightwake Limited
• Original Assignee: Brightwake Limited
• Inventors: Cotton, Stephen
• Application Number:
  US14/355,301
• Publication Number:
  US 20140309574A1
• Time in Patent Office: Days
• US Class Current: 602/44
• 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 13/01012 being made of natural material, e.g. cellulose-, protein-, collagen-based
• CPC Class Codes: A61F 13/01021 characterised by the structure of the dressing
• CPC Class Codes: A61F 13/0209 comprising superabsorbent material
• CPC Class Codes: A61F 13/05 specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT]
• CPC Class Codes: A61F 13/2005 specially adapted for the nose cavity
• CPC Class Codes: A61F 2013/00174 possibility of applying pressure
• CPC Class Codes: A61F 2013/00229 with alginate
• CPC Class Codes: A61F 2013/00242 to avoiding fraying or pilling lint-free, i.e. non-linting or frying A61F2013/00348
• CPC Class Codes: A61F 2013/00536 for draining or irrigating wounds
• CPC Class Codes: A61F 2013/0054 for deep wounds
• CPC Class Codes: A61F 2013/0091 with disinfecting or anaesthetics means, e.g. anti-mycrobic
• CPC Class Codes: A61L 15/225 Mixtures of macromolecular compounds
• CPC Class Codes: A61L 15/40 containing ingredients of undetermined constitution or reaction products thereof , e.g. plant or animal extracts
• CPC Class Codes: A61L 15/425 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 15/44 Medicaments
• CPC Class Codes: A61L 15/60 Liquid-swellable gel-forming materials, e.g. super-absorbents
• CPC Class Codes: A61L 2300/206 Biguanides, e.g. chlorohexidine
• CPC Class Codes: A61M 1/912 Connectors between dressing and drainage tube
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/962 : having pumping means on the suction site, e.g. miniature pump on dressing or dressing capable of exerting suction
• CPC Class Codes: A61M 1/985 : the dressing itself forming the collection container
• CPC Class Codes: B32B 2262/06 : Vegetal fibres
• CPC Class Codes: B32B 2556/00 : Patches, e.g. medical patches, repair patches
• CPC Class Codes: B32B 5/024 : Woven fabric
• CPC Class Codes: B32B 5/026 : Knitted fabric
• CPC Class Codes: B32B 5/245 : another layer next to it being a foam layer
• CPC Class Codes: C08L 1/02 : Cellulose; Modified cellulose
• CPC Class Codes: C08L 5/00 : Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
• CPC Class Codes: D02G 3/04 : Blended or other yarns or threads containing components made from different materials
• CPC Class Codes: D02G 3/448 : Yarns or threads for use in medical applications D02G3/449 takes precedence; surgical suture materials A61L17/00
• CPC Class Codes: D04B 21/16 : incorporating synthetic threads
• CPC Class Codes: D06N 2205/04 : Foam
• CPC Class Codes: D06N 2211/18 : Medical, e.g. bandage, prostheses, catheter medical patches D06N2211/22; medical packaging D06N2211/20
• CPC Class Codes: D06N 3/0015 : using fibres of specified chemical or physical nature, e.g. natural silk
• CPC Class Codes: D06N 3/0052 : obtained by leaching out of a compound, e.g. water soluble salts, fibres or fillers; obtained by freezing or sublimation; obtained by eliminating drops of sublimable fluid
• CPC Class Codes: D10B 2201/20 : Cellulose-derived artificial fibres
• CPC Class Codes: D10B 2509/022 : Wound dressings

Abstract

Wound dressings, methods for their production and components for use therein. A knitted structure comprising a blend of gelling fibres and non-gelling fibres wherein the yarn comprises at least 50% w/w gelling fibres, a three-dimensional textile material comprising gelling fibres, and a yarn comprising a blend of gelling and non-gelling fibres which may be used in their production, the knitted structure and three-dimensional textile material beings suitable for use as wound dressings or as components of composite wound dressings. The wound dressings may be adapted for use in negative pressure wound therapy (NPWT). It has been found that the incorporation of gel-forming fibres provides a material which has a high absorbency, enabling good transfer of exudates away from a wound, which retains structural integrity, and which is non-adherent and easily removed from the wound.

Claims

1. A knitted structure for use as, or as a component of, a wound dressing, the structure being knitted from yarn spun from a blend of gelling fibres and cellulosic non-gelling fibres, wherein the yarn comprises at least 50% w/w gelling fibres.

5. The knitted structure of claim 1, wherein the gelling fibres are fibres selected from the group consisting of pectin fibres, alginate fibres, fibres made from alginate and another polysaccharide, chitosan fibres, hyaluronic acid fibres, fibres of other polysaccharides or derived from gums and chemically-modified cellulosic fibres, or combinations thereof.

6. The knitted structure of claim 5, wherein the gelling fibres are alginate fibres and/or pectin fibres.

7. The knitted structure of claim 6, wherein the gelling fibres are calcium alginate.

9. The knitted structure of claim 1, wherein the cellulosic fibres are lyocell or viscose.

10. The knitted structure of claim 1, wherein the knitted structure comprises calcium alginate and viscose.

11. The knitted structure of claim 1, which wherein the knitted structure comprises calcium alginate and lyocell.

12. The knitted structure of claim 1, wherein the knitted structure comprises pectin and viscose.

13. The knitted structure of claim 1, wherein the knitted structure comprises pectin and lyocell.

18. The knitted structure of claim 1, further comprising one or more additional agents selected from antimicrobial agents, antiseptic agents, antifungal agents and/or anti-inflammatory agents.

19. The knitted structure of claim 18, wherein the knitted structure is impregnated or coated with honey.

20. The knitted structure of claim 18, wherein the knitted structure incorporates polyhexamethylene biguanide.

49. A composite wound dressing comprising the knitted structure of claim 1.

50. The composite wound dressing of claim 49, which further comprises a backing layer.

51. The composite wound dressing of claim 50, wherein the backing layer has a moisture vapour transmission rate of at least 300 g/m²/24 h.

52. The composite wound dressing of claim 50, wherein the backing layer is a polyurethane film.

53. The composite wound dressing of claim 50, wherein the backing layer extends beyond the edge of the three-dimensional textile material on all sides, forming a border around the three-dimensional textile material.

54. The composite wound dressing of claim 50, wherein the backing layer carries an adhesive on its underside.

55. The composite wound dressing of claim 54, wherein the adhesive is an acrylic adhesive.

56. The composite wound dressing of claim 49, wherein the entire underside of the wound dressing carries an adhesive layer.

57. The composite wound dressing of claim 56, wherein the adhesive layer comprises perforations.

58. The composite wound dressing of claim 57, wherein the perforations have a diameter of 4-10 mm.

59. The composite wound dressing of claim 49, wherein the underside of the wound dressing carries an adhesive layer formed with a central opening through which the three-dimensional material is exposed.

60. The composite wound dressing of claim 59, wherein the adhesive layer comprises perforations.

61. The composite wound dressing of claim 59, wherein the adhesive layer is a silicone gel.

62. The composite wound dressing of claim 61, wherein the silicone gel is carried on a layer of melt-blown non-woven material.

63. The composite wound dressing of claim 62, wherein the melt-blown non-woven material is melt-blown polyurethane (MBPU).

64. The composite wound dressing of claim 63, wherein a reverse side of the MBPU is coated with an acrylic adhesive.

65. The composite wound dressing of claim 49, which further comprises an absorbent body.

66. The composite wound dressing of claim 65, wherein the absorbent body is a foam pad.

67. The composite wound dressing of claim 65, wherein the absorbent body is a polymeric superabsorbent material.

68. The composite wound dressing of claim 49, wherein the wound dressing further comprises a releasable liner.

69. The composite wound dressing of claim 49, further comprising one or more additional agents selected from antimicrobial agents, antiseptic agents, antifungal agents and/or anti-inflammatory agents.

2. A yarn spun from a blend of gelling fibres and cellulosic non-gelling fibres, wherein the yarn comprises at least 50% w/w gelling fibres.

3. The yarn of claim 2, produced using staple fibres which have a length greater than 30 mm.

4. The yarn of claim 3, produced using staple fibres which have a length greater than 40 mm.

14. The yarn of claim 2, wherein the yarn comprises between 60% and 90% w/w gelling fibres.

15. The yarn of claim 2, wherein the yarn comprises between 70% and 90% w/w gelling fibres.

16. The yarn of claim 2, wherein the yarn comprises approximately 80% w/w gelling fibres.

17. The yarn of claim 2, wherein the yarn is a textured yarn.

73. The yarn of claim 2, wherein the gelling fibres are fibres selected from the group consisting of pectin fibres, alginate fibres, fibres made from alginate and another polysaccharide, chitosan fibres, hyaluronic acid fibres, fibres of other polysaccharides or derived from gums and chemically-modified cellulosic fibres, or combinations thereof.

74. The yarn of claim 73, wherein the gelling fibres are alginate fibres and/or pectin fibres.

75. The yarn of claim 74, wherein the gelling fibres are calcium alginate.

76. The yarn of claim 2, wherein the cellulosic fibres are lyocell or viscose.

77. The yarn of claim 2, wherein the yarn comprises calcium alginate and viscose.

78. The yarn of claim 2, wherein the yarn comprises calcium alginate and lyocell.

79. The yarn of claim 2, wherein the yarn comprises pectin and viscose.

80. The yarn of claim 2, wherein the yarn comprises pectin and lyocell.

8. (canceled)

21. A gelling foam dressing, comprising a sheet of gelling foam laminated with a scrim comprising gelling fibres and non-gelling fibres.

27. A method of manufacturing a gelling foam dressing according to claim 21, comprising:

a) casting a solution of gelling material into a mould,

b) allowing the solution to partially cure,

c) laying the scrim on top of the partially-cured solution,

d) allowing the solution to cure further to form a hydrogel, and

e) removing water from the hydrogel to form a foam sheet bonded to the scrim.

22-26. -26. (canceled)

28-32. -32. (canceled)

33. A three-dimensional textile spacer fabric material comprising gelling fibres.

46. A wound dressing comprising a three-dimensional textile material according to claim 33.

70. A wound dressing for use in negative pressure wound therapy, the wound dressing comprising an occlusive backing layer fitted with a drainage port, and a three-dimensional textile material according to claim 33.

34-45. -45. (canceled)

47-48. -48. (canceled)

71-72. -72. (canceled)