Perforated binder for laminated wound dressing

Abstract

A binder layer for a laminated wound dressing is brought into contact with a sheet coated with a pattern-coated adhesive sheet. As the binder layer is in contact with the pattern-coated adhesive sheet, a series of closed-loop cuts are made in the binder layer. The closed-loop cuts are made in such a way that the material enclosed by each closed loop is substantially physically separated from the remainder of the binder layer. Then the binder layer is moved away from the pattern-coated adhesive sheet, so that the binder layer and the pattern-coated adhesive sheet are no longer in contact. When the binder layer and the pattern-coated adhesive sheet are moved apart, the material enclosed in the closed-loop cuts—i.e., the cut waste fragments—are retained on the pattern-coated adhesive sheet, ensuring that the binder layer includes a series of cleared perforations.

Claims

1. A method of fabricating a laminated dressing comprising: bringing a binder layer into contact with a pattern-coated adhesive sheet; making a series of closed-loop cuts in the binder layer; and moving the binder layer away from the pattern-coated adhesive sheet, such that the binder layer and the pattern-coated adhesive sheet are no longer in contact, such that a material enclosed in the closed-loop cuts is retained on the pattern-coated adhesive sheet, whereby the binder layer includes a series of cleared perforations.

2. The method of claim 1 wherein said binder layer is fabricated from a polyester or polyamide material.

3. The method of claim 1, further comprising positioning the binder layer between a lower layer and an upper layer.

4. The method of claim 3, wherein the lower layer comprises a fiber material configured to directly contact a patient's skin and a wound area.

5. The method of claim 3, wherein the upper layer comprises a foam material configured to absorb exudate and moisture.

6. The method of claim 3, wherein the lower layer comprises a fiber material configured to directly contact a patient's skin and a wound area and the upper layer comprises a foam material configured to absorb exudate and moisture.

7. The method of claim 3, further comprising forming the lower layer from a non-woven, spunlaced polymer fabric.

8. The method of claim 3, further comprising forming the lower layer from polyethylene fibers.

9. The method of claim 8, further comprising coating at least some of the polyethylene fibers with silicone.

10. The method of claim 3, further comprising forming the lower layer from regenerated cellulose fiber material.

11. The method of claim 10, further comprising including silicone in at least some of the regenerated cellulose fiber material.

12. The method of claim 3, wherein said upper layer is fabricated from polyurethane.

13. The method of claim 3, further comprising including an antimicrobial agent in the upper layer.

14. The method of claim 13, wherein the antimicrobial agent is inorganic.

15. The method of claim 13 wherein said antimicrobial agent is metal-based.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) The above-mentioned and additional features of the invention will become more clearly understood from the following detailed description of the invention read together with the drawings in which:

(2) FIG. 1 is an exploded view of an example embodiment of the present invention;

(3) FIG. 2A is a view of one stage of one embodiment of a process for removing cut material from a binder layer to form a perforated binder layer, showing an unperforated binder layer and a pattern-coated adhesive sheet;

(4) FIG. 2B is a view of another stage of the example embodiment process shown in FIG. 2A, showing the binder layer in contact with the pattern-coated adhesive sheet;

(5) FIG. 2C is a view of another stage of the example embodiment process shown in FIGS. 2A and 2B, showing the now-perforated binder layer moved away from the pattern-coated adhesive sheet; and

(6) FIG. 3 is a perspective view of one embodiment of a process for form a perforated binder layer.

DETAILED DESCRIPTION OF THE INVENTION

(7) The present invention in some of its embodiments is directed toward a process of fabricating a perforated binder for a laminated dressing.

(8) According to one embodiment of the present general inventive concept, illustrated generally at FIG. 1, a laminated dressing 10 comprises three layers: a lower layer 20, comprising a fiber material, to directly contact a patient's skin and a wound area; an upper layer 30, comprising a foam or foam-like material to absorb exudate and moisture; and a middle layer or binder layer 40 (hereinafter “binder layer”), comprising a binder material to bind the fiber-based lower layer 20 and the foam-based upper layer 30. When the dressing 10 is applied to a patient's skin and wound, the fiber-based lower layer 20 is placed in direct contact with the patient's skin, generally covering the wound at least in part; the binder layer 40 and foam-based upper layer 30 sit on top of the fiber-based lower layer 20 with respect to the patient's skin.

(9) Generally, during the manufacture or fabrication of a multi-layer or laminated dressing like the example embodiment dressing 10 illustrated in FIG. 1, the layers are brought together and heated in order to promote the formation of bonds—including, in various embodiments and depending on the materials used, physical and chemical bonds—between the multiple layers. The binder layer 40 generally comprises a polymer-based fiber, such as a polyester or polyamide fiber, or a blend of such materials. Often, during the heating process, a polymer-based binder layer 40 melts; when the melted binder layer 40 re-solidifies at a later stage, the resulting binder layer 40 is largely moisture-impermeable and therefore inhibits the transmigration of exudate or other moisture from the lower layer 20 to the upper layer 40. The melting of the binder layer 40 during the fabrication process results in a binder layer 40 that inhibits the proper function of the laminated dressing 10, which aims to allow the foam-based upper layer 30 draw moisture and exudate away from the wound and the lower layer 20 in order to keep the wound dry and inhibit infection and irritation.

(10) One way to limit the counterproductive results of the melting of the binder layer 40 during the fabrication process is to cut perforations or holes 44 in the binder layer 40 before [[it]] the binder layer 40 is positioned between the lower layer 20 and the upper layer 30. Thus, for example, in the exploded view of an illustrated example embodiment, shown in FIG. 1, the binder layer 40 includes numerous perforations 44. The pre-cut perforations 44 (pre-cut in so far as the excised material is removed from the binder layer 40 before said binder layer 40 is inserted between the lower layer 20 and the upper layer 30) ensure that, when the binder layer 40 has melted, and then re-solidified after cooling, the re-solidified binder layer 40 still includes perforations, through which moisture and exudate may pass from the lower layer 20 to the upper layer 30.

(11) However, when cutting holes 44 in a sheet of material for a binder layer, it is necessary to ensure that the cut-out material from the binder layer 40 physically separates from the binder layer 40 before the binder layer 40 is positioned between the lower layer 20 to the upper layer 30. In some example embodiments of the present general inventive concept, cut-out material from the binder layer 40 is physically separated from the binder layer 40 by adhering the cut-out material to a sheet covered with an adhesive material, such as a glue material. One example embodiment of a process according to one aspect of the present general inventive concept is illustrated generally in FIGS. 2A through 2C. In FIG. 2A, a binder layer 40 is brought into contact with a sheet 50 coated with a pattern of adhesive material (hereinafter, “pattern-coated adhesive sheet”). In FIG. 2B, the binder layer 40 is shown in contact with the pattern-coated adhesive sheet 50, with one face of the binder layer 40 substantially pressed against one face of the pattern-coated adhesive sheet 50. As the binder layer 40 is in contact with the pattern-coated adhesive sheet 50, a series of closed-loop cuts are made in the binder layer 40, generally along the phantom lines 41 shown on the binder layer 40 in FIGS. 2A and 2B. The closed-loop cuts are made in such a way that the material enclosed by each closed loop is substantially physically separated from the remainder of the binder layer 40. In FIG. 2C, the binder layer 40 is moved away from the pattern-coated adhesive sheet 50, so that the binder layer 40 and the pattern-coated adhesive sheet 50 are no longer in contact. When the binder layer 40 and the pattern-coated adhesive sheet 50 are moved apart, the material enclosed in the closed-loop cuts—i.e., the cut waste fragments 42—are retained on the pattern-coated adhesive sheet, ensuring that the binder layer 40 includes a series of cleared perforations 44.

(12) FIG. 3 illustrates one embodiment of a process for fabricating a perforated binder layer according to the present general inventive concept. In the illustrated example embodiment, a roll of binder layer 410 is unspooled and brought into contact with a roll of pattern-coated adhesive sheet 510, and the two rolls in contact are moved onto an assembly line 700. On the assembly line 700, a rolling cutter 600 is positioned above the roll of binder layer 410. The rolling cutter 600 includes a series of cutting punches 610, which make closed-loop cuts in the roll of binder layer 410. Then the binder layer 410 is moved away from the pattern-coated adhesive sheet 510, so that the binder layer 410 and the pattern-coated adhesive sheet 510 are no longer in contact. When the binder layer 410 and the pattern-coated adhesive sheet 510 are moved apart, the material enclosed in the closed-loop cuts—i.e., the cut waste fragments 420—are retained on the roll of pattern-coated adhesive sheet 510, ensuring that the binder layer 410 includes a series of cleared perforations 440.

(13) In some embodiments, the lower layer comprises polyethylene fibers. In some embodiments, the lower layer comprises a porous mesh of polyethylene fibers. In some embodiments, the lower layer comprises a spun regenerated fiber material. In some embodiments, some or all of the fibers are coated with silicone. In some embodiments, the fibers are not coated with silicone.

(14) In some embodiments, the foam-based upper layer comprises a foam fabricated from a hydrophilic polyurethane or comparable material. In some embodiments, the foam-based upper layer includes a metal-based antimicrobial agent that undergoes a controlled release when the binder layer comes into contact with moisture. In some embodiments, the upper layer includes an inorganic antimicrobial agent. In some embodiments, the upper layer does not include an inorganic antimicrobial agent.

(15) When the dressing is used, the lower layer is applied directly to a patient's skin, covering or substantially covering the wound. The silicone in the lower layer interacts with the wound to minimize the appearance of scar tissue.

(16) The dressing is either pre-wetted or applied dry to the wound. Moisture, either applied beforehand or from the wound exudate, travels through the porous fiber-based lower layer, through the binder layer, into the foam upper layer.

(17) In some embodiments, moisture acts to release metal ions from controlled-release mechanisms, such as zeolites containing the metal ions, in the foam-based upper layer. The ions then travel within the moisture into the wound, where they act to kill bacteria and other infectious microorganisms and to prevent infections from gaining a foothold.

(18) While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept.