Composite article suitable for use as a wound dressing
A composite article comprises a fluid transport layer having first and second surfaces and a hydrophobic layer applied to the first surface of the fluid transport layer. When the composite article is used as a wound dressing, the first surface of the fluid transport layer provides a skin-facing surface. The hydrophobic layer comprises a plurality of discontinuities, and at least a portion of the discontinuities have a dimension sufficient to permit the passage of fluid through the hydrophobic layer and into the fluid transport layer.
1. A composite article comprising:
(a) a fluid transport layer, the fluid transport layer having a first surface and a second surface, the first surface of the fluid transport layer having a first surface energy, and the second surface of the fluid transport layer having a second surface energy, the second surface energy being greater than the first surface energy, and
(b) a hydrophobic layer applied to the first surface of the fluid transport layer, the hydrophobic layer having a third surface energy, the third surface energy being less than the first surface energy, the hydrophobic layer comprising a plurality of discontinuities, at least a portion of the discontinuities having a dimension sufficient to permit the passage of fluid through the hydrophobic layer and into the fluid transport layer,
wherein the fluid transport layer is a jersey knit textile material comprising a first yarn forming a plurality of interlocking loops and at least one effect yarn tucked into the interlocking loops formed by the first yarn, wherein the plurality of interlocking loops formed by the first yarn provide the second surface of the fluid transport layer, and wherein the first yarn is more hydrophilic than the effect yarn.
2. The composite article of claim 1 , wherein the first yarn comprises a polyamide and the effect yarn comprises a polyester.
3. The composite article of claim 2 , wherein the fluid transport layer further comprises one or more elastomeric yarns.
4. The composite article of claim 1 , wherein the hydrophobic layer comprises a material selected from the group consisting of apertured polymeric films, fluorochemicals, hydrophobic, pressure sensitive adhesives, waxy compounds, silicones, hydrophobic acrylic polymers, polyvinyl chloride-based polymers, and combinations thereof.
5. The composite article of claim 4 , wherein the hydrophobic layer comprises an apertured polymeric film.
6. The composite article of claim 4 , wherein the hydrophobic layer comprises a fluorochemical.
7. The composite article of claim 4 , wherein the hydrophobic layer comprises a hydrophobic, pressure sensitive adhesive.
8. The composite article of claim 4 , wherein the hydrophobic layer comprises a waxy compound.
9. The composite article of claim 4 , wherein the hydrophobic layer comprises a silicone.
10. The composite article of claim 4 , wherein the hydrophobic layer comprises a hydrophobic acrylic polymer.
11. The composite article of claim 1 , wherein the hydrophobic layer comprises a plurality of discontinuities having a dimension of from about 7 μm to about 3,000 μm.
12. The composite article of claim 11 , wherein the hydrophobic layer comprises a plurality of discontinuities having a dimension of from about 50 μm to about 500 μm.
13. The composite article of claim 11 , wherein the hydrophobic layer comprises a plurality of discontinuities having a dimension of from about 100 μm to about 300 μm.
14. The composite article of claim 1 , wherein the composite article further comprises a moisture vapor permeable film, the moisture vapor permeable film being positioned so that it is adjacent to the second surface of the fluid transport layer.
15. The composite article of claim 14 , wherein the moisture vapor permeable film is a polyurethane film comprising a polyurethane polymer selected from the group consisting of polyether-based polyurethanes, polyester-based polyurethanes, and combinations thereof.
16. The composite article of claim 14 , wherein the moisture vapor permeable film exhibits a moisture vapor transmission rate (MVTR) of about 500 g/m 2 /24 hr or more.
17. The composite article of claim 1 , wherein the composite article further comprises a fluid retentive layer, the fluid retentive layer having a first surface and a second surface, the first surface of the fluid retentive layer having a fourth surface energy, the fourth surface energy being greater than the second surface energy, and the fluid retentive layer being positioned so that the first surface of the fluid retentive layer is adjacent to the second surface of the fluid transport layer.
18. The composite article of claim 17 , wherein the fluid retentive layer is selected from the group consisting of foams, textile materials, alginates, superabsorbent polymers, gels, hydrocolloids, and combinations thereof.
19. The composite article of claim 18 , wherein the fluid retentive layer comprises a polyester-based polyurethane foam.
20. The composite article of claim 17 , wherein the composite article further comprises a moisture vapor permeable film, the moisture vapor permeable film being positioned so that it is adjacent to the second surface of the fluid retentive layer.
21. The composite article of claim 20 , wherein the moisture vapor permeable film is a polyurethane film comprising a polyurethane polymer selected from the group consisting of polyether-based polyurethanes, polyester-based polyurethanes, and combinations thereof.
22. The composite article of claim 21 , wherein the moisture vapor permeable film exhibits a moisture vapor transmission rate (MVTR) of about 500 g/m 2 /24 hr or more.