HIGH HYGROSCOPIC WOUND DRESSING AND PREPARATION METHOD AND USE THEREOF

Abstract

The present invention discloses a wound dressing and the method of manufacturing. The wound dressing is a knitted fabric including of a fluffy layer of gel-forming fibers and a backing layer of non-gel-forming fibers. The backing layer includes a plain fabric of the non-gel-forming fibers. The gel-forming fibers are knitted onto the backing layer, a middle part of the gel-forming fibers are held in the backing layer, and two ends of the gel-forming fibers project against the backing layer. The length of the middle part of the gel-forming fibers is no more than the length of one loop of the non-gel-forming fibers, and the length of each of the two ends of the gel-forming fibers is between 1-100 mm.

Claims

1. An absorbent wound dressing adapted to be applied on wounds and left in place for several days to promote wound healing, the absorbent wound dressing comprising a backing layer of non-gel-forming fibers, and a layer of gel-forming fibers knitted on the backing layer, wherein: the gel-forming fibers are alginate fibers, chemically modified cellulose fibers, chitosan fibers, or a mixture thereof; the non-gel-forming fibers are polyester filaments or yarns, nylon filaments or yarns, PVA filaments or yarns, viscose filaments or yarns, lyocell filaments or yarns, non-gel-forming chitosan filaments or yarns, polyurethane filaments or yarns, polypropylene filaments or yarns, cotton yarns, or a mixture thereof; the backing layer comprises a plain fabric of the non-gel-forming fibers; a middle part of the gel-forming fibers forms loops, and are tied in the backing layer, and two ends of the gel-forming fibers project against the backing layer; a length of the middle part of the gel-forming fibers is no more than a length of one loop of the non-gel-forming fibers, and a length of each of the two ends of the gel-forming fibers is between 1 and 100 mm.

2. The absorbent wound dressing of claim 1, wherein the length of one loop of the non-gel-forming fibers is between 1 and 40 mm.

3. The absorbent wound dressing of claim 1, wherein the length of one loop of the non-gel-forming fibers is between 2 and 20 mm.

4. The absorbent wound dressing of claim 1, wherein the wound dressing has an absorption capacity of 6 g/100 cm.sup.2 or more when tested according to EN 13726-1:2002/AC:2003.

5. The absorbent wound dressing of claim 1, wherein the wound dressing, when cut in the cross-machine direction, curls by itself into a fabric roll with the backing layer inside and the layer of the gel-forming fibers outside.

6. The absorbent wound dressing of claim 1, wherein a linear density of the gel-forming fibers is 1-10 dtex.

7. The absorbent wound dressing of claim 1, wherein the length of each of the two ends of the gel-forming fibers is 10-75 mm.

8. The absorbent wound dressing of claim 1, wherein a linear density of the non-gel-forming fibers is 50-500 dtex.

9. The absorbent wound dressing of claim 1, wherein the length of each of the two ends of the gel-forming fibers is between 5 and 50 mm.

10. The absorbent wound dressing of claim 1, wherein the alginate fibers are calcium alginate or calcium/sodium alginate fibers.

11. The absorbent wound dressing of claim 1, wherein the chemically modified cellulose fibers are carboxymethyl cellulose fibers or sulfonated solvent spun cellulose fibers, the sulfonated solvent spun cellulose fibers being water insoluble.

12. The absorbent wound dressing of claim 1, wherein the chitosan fibers are carboxymethyl chitosan fibers or acylated chitosan fibers.

13. The absorbent wound dressing of claim 1, wherein the gel-forming fibers comprise an antimicrobial agent.

14. The absorbent wound dressing of claim 1, wherein the absorbent wound dressing is adapted to be applied on wounds and left in place for up to seven days to promote wound healing.

15. A method of manufacturing the absorbent wound dressing of claim 1, the method comprising: 1) feeding the non-gel-forming fibers into a circular knitting machine to form the backing layer; 2) feeding the gel-forming fiber into the circular knitting machine, and knitting the gel-forming fibers into the backing layer through front blow or back blow to obtain a knitted fabric; 3) cutting the knitted fabric, calendaring; and 4) packing the knitted fabric into pouches, and sterilizing through gamma irradiation, EtO or autoclave.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] FIG. 1 is an illustration of the backing layer in accordance with one embodiment of the disclosure;

[0037] FIG. 2 is an illustration of an absorbent wound dressing in accordance with one embodiment of the disclosure;

[0038] FIG. 3 is an illustration of an absorbent wound dressing in accordance with another embodiment of the disclosure.

EXAMPLE

[0039] To further illustrate, embodiments detailing an absorbent wound dressing are described below. It should be noted that the following embodiments are intended to describe and not to limit the disclosure.

[0040] As shown in FIG. 1, the disclosure provides an absorbent wound dressing, comprising a fluffy layer of gel-forming fibers 1 and a backing layer of non-gel-forming fibers 2. The backing layer comprises a plain fabric of the non-gel-forming fibers. The plain fabric of the non-gel-forming fibers has a pattern of FIG. 1, and is obtained through the known plain knitting technology. The plain fabric comprises rows of loops of the non-gel-forming fibers 2, and each row of the loops is intermeshed with a preceding row of loops. One loop refers to the non-gel-forming fibers 2 from A to B as shown in FIG. 2. The length of one loop of the non-gel-forming fibers is between 1 and 40 mm, preferably between 2 and 20 mm. The gel-forming fibers 1 are knitted onto the backing layer, a middle part of the gel-forming fibers 1 forms loops, and are held in the backing layer, and the two ends of the gel-forming fibers 1 are not held inside, but project against the backing layer. The length of the middle part of the gel-forming fibers 1 that is held by the back layer is no more than the length of one loop of the non-gel-forming fibers 2, and the length of each of the two ends of the gel-forming fibers is between 1-100 mm, preferably 5-50 mm. Preferably, the length of the middle part of the gel-forming fibers is between 2 and 20 mm. The non-gel-forming fibers 2 are polyester filaments or yarns, nylon filaments or yarns, polyvinyl alcohol (PVA) filaments or yarns, viscose filaments or yarns, Lyocell filaments or yarns, non-gel-forming chitosan filaments or yarns, polyurethane filaments or yarns, polyethylene filaments or yarns, polypropylene filaments or yarns, silk yarns, cotton yarns, or a mixture thereof. The gel-forming fibers 1 are alginate fibers, chemical modified cellulose fibers, chemically modified chitosan fiber, or a mixture thereof.

Example 1

[0041] Feed 2183 dtex Lyocell filaments into the WHCW-S18C-24B-1056 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 18/inch. The backing layer has a structure as shown in FIG. 1.

[0042] Feed the calcium alginate slivers (linear density 6.7 g/m) into the above knitting machine. The fiber linear density is 2.65 dtex and the number of slivers is 18.

[0043] The blow method: front.

[0044] The fabric obtained has a structure of FIG. 2, and has the weight of 410 g/m.sup.2.

[0045] The length of free fiber of the fluffy layer is 40 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 45 g/100 cm.sup.2.

[0046] The fabric dry strength in MD is 150 N/cm, elongation is 90%. The fabric wet strength is 145 N/cm, elongation is 93%. The fabric dry strength in CD is 41 N/cm, elongation is 266%. The fabric wet strength is 40 N/cm, elongation is 240%.

Example 2

[0047] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0048] Feed the calcium/sodium alginate slivers (linear density 6.7 g/m) into the above knitting machine. The fiber linear density is 2.65 dtex and the number of slivers is 9.

[0049] The blow method: back.

[0050] The fabric obtained has a structure of FIG. 3, and has the weight of 320 g/m.sup.2.

[0051] The length of free fiber of the fluffy layer is 12 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 32 g/100 cm.sup.2.

[0052] The fabric dry strength in MD is 109 N/cm, elongation is 128%. The fabric wet strength is 100 N/cm, elongation is 115%. The fabric dry strength in CD is 44 N/cm, elongation is 192%. The fabric wet strength is 41 N/cm, elongation is 168%.

Example 3

[0053] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0054] Feed the carboxymethyl cellulose fiber sliver (linear density 6 g/m) into the above knitting machine. The fiber linear density is 2.1 dtex and the number of slivers is 9.

[0055] The blow method: back.

[0056] The fabric obtained has a structure of FIG. 3, and has the weight of 300 g/m.sup.2.

[0057] The length of free fiber of the fluffy layer is 8 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 33 g/100 cm.sup.2.

[0058] The fabric dry strength in MD is 105 N/cm, elongation is 120%. The fabric wet strength is 95 N/cm, elongation is 105%. The fabric dry strength in CD is 42 N/cm, elongation is 182%. The fabric wet strength is 39 N/cm, elongation is 165%.

Example 4

[0059] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0060] Feed acylated chitosan slivers (linear density 6 g/m) into the above knitting machine. The fiber linear density is 2.2 dtex and the number of slivers is 9.

[0061] The blow method: back.

[0062] The fabric obtained has a structure of FIG. 3, and has the weight of 290 g/m.sup.2.

[0063] The length of free fiber of the fluffy layer is 5 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 32 g/100 cm.sup.2.

[0064] The fabric dry strength in MD is 101 N/cm, elongation is 128%. The fabric wet strength is 92 N/cm, elongation is 112%. The fabric dry strength in CD is 39 N/cm, elongation is 180%. The fabric wet strength is 40 N/cm, elongation is 176%.

Example 5

[0065] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0066] Feed calcium alginate slivers (linear density 6.7 g/m) into the above knitting machine. The fiber linear density is 2.65 dtex and the number of slivers is 9.

[0067] The blow method: back.

[0068] The fabric obtained has a structure of FIG. 3, and has the weight of 300 g/m.sup.2.

[0069] The length of free fiber of the fluffy layer is 8 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 30 g/100 cm.sup.2.

[0070] The fabric dry strength in MD is 106 N/cm, elongation is 116%. The fabric wet strength is 197 N/cm, elongation is 103%. The fabric dry strength in CD is 41 N/cm, elongation is 180%. The fabric wet strength is 37 N/cm, elongation is 159%.

Example 6

[0071] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0072] Feed silver alginate slivers (linear density 6.7 g/m) into the above knitting machine. The fiber linear density is 2.75 dtex and the number of slivers is 9.

[0073] The blow method: back.

[0074] The fabric obtained has the weight of 320 g/m.sup.2.

[0075] The length of free fiber of the fluffy layer is 12 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 31 g/100 cm.sup.2.

[0076] The fabric dry strength in MD is 110 N/cm, elongation is 120%. The fabric wet strength is 105 N/cm, elongation is 113%. The fabric dry strength in CD is 39 N/cm, elongation is 190%. The fabric wet strength is 42 N/cm, elongation is 170%.

Example 7

[0077] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0078] Feed PHMB alginate slivers (linear density 6.7 g/m) into the above knitting machine. The fiber linear density is 2.75 dtex and the number of slivers is 9.

[0079] The blow method: back.

[0080] The fabric obtained has a structure of FIG. 3, and has the weight of 320 g/m.sup.2.

[0081] The length of free fiber of the fluffy layer is 12 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 31 g/100 cm.sup.2.

[0082] The fabric dry strength in MD is 101 N/cm, elongation is 124%. The fabric wet strength is 98 N/cm, elongation is 114%. The fabric dry strength in CD is 45 N/cm, elongation is 188%. The fabric wet strength is 40 N/cm, elongation is 166%.

Example 8

[0083] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0084] Feed silver carboxymethyl cellulose slivers (linear density 6 g/m) into the above knitting machine. The fiber linear density is 2.2 dtex and the number of slivers is 9.

[0085] The blow method: back.

[0086] The fabric obtained has a structure of FIG. 3, and has the weight of 300 g/m.sup.2.

[0087] The length of free fiber of the fluffy layer is 8 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 32 g/100 cm.sup.2.

[0088] The fabric dry strength in MD is 103 N/cm, elongation is 118%. The fabric wet strength is 96 N/cm, elongation is 104%. The fabric dry strength in CD is 38 N/cm, elongation is 176%. The fabric wet strength is 35 N/cm, elongation is 143%.

Example 9

[0089] Feed 2167 dtex polyester filaments into the WHCW-S18C-27A-1176 circular knitting machine. The needle gauge is 14 needles/inch, the backing layer density is 20/inch. The backing layer has a structure as shown in FIG. 1.

[0090] Feed silver acylated chitosan slivers (linear density 6 g/m) into the above knitting machine. The fiber linear density is 2.3 dtex and the number of slivers is 9.

[0091] The blow method: back.

[0092] The fabric obtained has a structure of FIG. 3, and has the weight of 300 g/m.sup.2.

[0093] The length of free fiber of the fluffy layer is 5 mm. The absorbency measured by EN 13726-1:2002/AC:2003 is 31 g/100 cm.sup.2.

[0094] The fabric dry strength in MD is 98 N/cm, elongation is 125%. The fabric wet strength is 90 N/cm, elongation is 117%. The fabric dry strength in CD is 38 N/cm, elongation is 185%. The fabric wet strength is 44 N/cm, elongation is 186%.