Extensible dressings
The present invention relates to dressings such as bandages or tapes having improved extensibility and conformability to human skin and joints.
1. An adhesive bandage comprising:
(a) a dressing comprising a layer of material comprising a laminate having a nonwoven layer comprising polyester fibers and a nonstick, high density polyethylene net, the layer of material having a plurality of material free regions, wherein:
(i) the material free regions are in the form of curvilinear sigmoid pattern units, the curvilinear sigmoidal pattern units having dimensions and oriented and arranged in a regular array such that the layer of material has a Stretchability Testxy extension in at least one of a 45° diagonal direction of at least 1125% more than the same layer of material without material free regions when applying a force of from 0.2 kgf along such 45° diagonal direction of the layer of material; and
(ii) the curvilinear sigmoidal pattern units have a width w and a length I, and further wherein the length I of the curvilinear sigmoidal pattern unit is from 1 to 6 times the width w of the curvilinear sigmoidal pattern unit; and
(b) a backing layer comprising an elastomeric film having an adhesive disposed on a major surface thereof and being adhered to the nonwoven layer of the laminate;
wherein, upon application of the adhesive bandage to a user's skin in a substantially unstressed condition, the dressing is capable of stretching with the skin during use to minimize detachment of the dressing therefrom.
2. The adhesive bandage of claim 1 , wherein the material free regions are cuts or slits in the layer of material.
3. The adhesive bandage of claim 1 , wherein the curvilinear sigmoidal pattern units are non-intersecting and arranged adjacent to one another to form one or more linear rows.
4. The adhesive bandage of claim 3 , wherein the linear rows are parallel to each other.
5. The adhesive bandage of claim 1 , wherein each curvilinear sigmoidal pattern unit has a top and further wherein the bottom of any curvilinear sigmoidal pattern unit in a row is aligned with the top and bottom of the other curvilinear sigmoidal pattern units in that row.
6. The adhesive bandage of claim 1 , wherein the length/of at least one curvilinear sigmoidal pattern unit is oriented perpendicular to the length/of an adjacent curvilinear sigmoidal pattern unit.
7. The adhesive bandage of claim 6 , wherein the length l of each curvilinear sigmoidal pattern unit in a row is oriented perpendicular to the length l of its adjacent curvilinear sigmoidal pattern unit in the row.
8. The adhesive bandage of claim 1 , wherein the surface density of curvilinear sigmoidal pattern units per square inch of the surface of the layer of material is from 10 pattern units/in 2 to 14 pattern units/in 2 of the surface of the layer of material.
9. The adhesive bandage of claim 1 , wherein the layer of material has a Stretchability Testxy extension in at least one of the 45° diagonal directions of at least 1725% more than the same layer of material without material free regions, when applying a force of from 0.3 kgf along such 45° diagonal direction of the layer of material.
10. The adhesive bandage of claim 1 , wherein the layer of material has a Stretchability Testxy extension in at least one of the 45° diagonal directions of at least 1650% more than the same layer of material without material free regions, when applying a force of from 0.4 kgf along such 45° diagonal direction of the layer of material.
11. The adhesive bandage of claim 1 , wherein the layer of material has a Stretchability Testxy extension in at least one of the longitudinal or transverse directions of at least 100% more than the same layer of material without material free regions, when applying a force of from 0.1 kgf along such longitudinal or transverse direction of the layer of material.
12. The adhesive bandage of claim 1 , wherein the layer of material has a Stretchability Testxy extension in at least one of the longitudinal or transverse directions of at least 150% more than the same layer of material without material free regions, when applying a force of from 0.2 kgf along such longitudinal or transverse direction of the layer of material.
13. The adhesive bandage of claim 1 , wherein the layer of material has a Stretchability Testxy extension in at least one of the longitudinal or transverse directions of at least 425% more than the same layer of material without material free regions when applying a force of from 0.3 kgf along such longitudinal or transverse direction of the layer of material.
14. The adhesive bandage of claim 11 , wherein the layer of material has a Stretchability Testxy extension in the other longitudinal or transverse direction of at least 75% more than the same layer of material without material free regions when applying a force of from 0.1 kgf along such other longitudinal or transverse direction of the layer of material.
15. The adhesive bandage of claim 12 , wherein the layer of material has a Stretchability Testxy extension in the other longitudinal or transverse direction of at least 150% more than the same layer of material without material free regions when applying a force of from 0.2 kgf along such other longitudinal or transverse direction of the layer of material.
16. The adhesive bandage of claim 1 , wherein the layer of material has a Stretchability Testz extension of at least 1 mm to 8 mm away from the xy-plane of the layer of material when applying a force of 0.5 kgf along the z direction of the layer of material.
17. The adhesive bandage of claim 1 wherein the backing layer comprises a polyurethane film.
18. The adhesive bandage of claim 17 wherein the backing layer further comprises a woven fabric.
19. The adhesive bandage of claim 1 wherein the wherein the length l of the curvilinear sigmoidal pattern unit is from 2.5 to 6 times the width w of the curvilinear sigmoidal pattern unit.