Bandage assembly with SAP coating

Abstract

A medical bandage or dressing includes an absorbent layer having at least one layer of polyurethane foam including a superabsorbent polymer additive. A medical bandage or dressing may include one or more hydrophilic nonwoven layers in combination with polyurethane foam, the one or more layers of the dressing may be heated and sealed to reduce shedding of superabsorbent polymer additives when the dressing absorbs liquid.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS Technical Field

[0001] This application claims the benefit of and priority to U.S. Provisional Patent Application Serial No. 63 / 441,490, filed on January 27, 2023, entitled “BANDAGE WITH SUPER ABSORBENT POLYMER,” U.S. Provisional Patent Application Serial No. 63 / 542,005, filed on October 2, 2023, entitled “BANDAGE COMPONENT WITH SAP COATING,” and U.S. Provisional Patent Application Serial No. 63 / 545,287, filed on October 23, 2023, entitled “BANDAGE COMPONENT WITH SAP COATING,” the entire contents of each of which are incorporated herein by reference. Background Art Technical Field

[0002] The present invention relates to a medical bandage or dressing having high liquid absorption. More specifically, the present invention relates to a bandage or dressing having an absorbent layer including one or more foam layers having superabsorbent polymers (SAPs) to absorb and retain wound exudate. Related existing technologies

[0003] Bandages and dressings that include absorbent materials are commonly used to cover wounds when wounds, burns, bedsores, and ulcers are healing. Bandages and dressings can also be used as preventive measures to prevent the formation of ulcers or wounds. Traditional bandages typically include an opening in an adhesive layer that contacts the user's skin, allowing exudate from the wound to be extracted from the wound site and absorbed by an absorbent layer that absorbs and retains the exudate. In traditional bandages and dressings, as the absorbent layer absorbs liquid, it tends to swell and harden, thereby reducing the flexibility of the bandage and tending to reduce the patient's comfort. The reduction in flexibility not only affects comfort, but may also reduce adhesion to the user's body when the user moves. In addition, the absorption capacity of many traditional bandages is limited, so that they may need to be replaced frequently, which is both labor-intensive and time-consuming, and may also increase the risk of infection or complications during the healing process.

[0004] Today's silicone foam dressings have revolutionized the industry because they allow for easy application of absorbent dressings and minimize trauma and scarring by providing an ideal moist environment for healing and comfort. However, polyurethane foams can limit the amount of water that can be absorbed.

[0005] Therefore, it would be beneficial to provide a bandage or dressing that is both soft and comfortable while also being able to better absorb and retain wound exudate. Summary of the Invention

[0006] An object of the present disclosure is to provide a foam dressing with improved comfort, absorbency and retention.

[0007] In an embodiment, a medical dressing according to one embodiment of the present disclosure includes: a carrier layer; an adhesive layer, which is provided below the carrier layer close to the user's skin when the medical dressing is placed in an appropriate position on the user; an absorbent layer, which is located below the adhesive layer and connected to the carrier layer through the adhesive layer, the absorbent layer being configured to absorb and retain exudate, and including at least one foam layer, on which a superabsorbent polymer additive is provided; and a wound contact layer, which is located below the absorbent layer and is configured to adhere to the user's skin, the wound contact layer including multiple openings, through which exudate can flow into the absorbent layer.

[0008] In an embodiment, the absorbent layer comprises a first polyurethane foam layer comprising at least a first layer of superabsorbent polymer additives and a second polyurethane foam layer comprising at least a second layer of superabsorbent polymer additives, wherein the exudate is absorbed by at least one of the first layer of superabsorbent polymer additives and the second layer of superabsorbent polymer additives.

[0009] In an embodiment, at least one of the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive comprises a binder powder configured to secure the superabsorbent polymer additive to the first polyurethane foam layer or the second polyurethane foam layer, respectively.

[0010] In an embodiment, the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive are provided in the form of powder and are impregnated into the first polyurethane foam layer and the second polyurethane foam layer, respectively.

[0011] In an embodiment, at least one of the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive comprises superabsorbent polymer additive provided via an aqueous solution.

[0012] In an embodiment, the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive include superabsorbent polymer additives provided via an aqueous solution.

[0013] In an embodiment, the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive are provided via aqueous solutions applied to the first and second polyurethane foam layers, respectively.

[0014] In an embodiment, the absorbent layer further comprises a third layer of superabsorbent polymer additive provided on at least one of the first polyurethane foam layer and the second polyurethane absorbent layer.

[0015] In an embodiment, the third layer superabsorbent polymer additive is a powder.

[0016] In an embodiment, the third layer of superabsorbent polymer additive is provided via an aqueous solution.

[0017] In an embodiment, the respective edges of the first polyurethane foam layer and the second polyurethane foam layer are sealed together to form a chamber to secure the superabsorbent polymer additive in place.

[0018] In an embodiment, the respective edges are sealed via ultrasonic welding.

[0019] In an embodiment, the dressing comprises a hydrophilic nonwoven fabric bonded to at least one of the first polyurethane foam layer and the second polyurethane foam layer over the superabsorbent polymer additive.

[0020] In an embodiment, the superabsorbent polymer additive is a powder impregnated in at least one foam layer.

[0021] In an embodiment, the superabsorbent polymer additive is provided via an aqueous solution.

[0022] In embodiments, the superabsorbent polymer additive remains on the at least one polyurethane foam layer after the liquid of the aqueous solution evaporates.

[0023] In an embodiment, the carrier layer is a polyurethane film.

[0024] In an embodiment, the plurality of openings formed in the wound contact layer are of the same size.

[0025] In an embodiment, the plurality of openings formed in the wound contact layer comprises a first set of larger openings located at the center of the dressing over the wound when the dressing is on the user's skin, and a second set of smaller openings located at the periphery of the dressing.

[0026] In an embodiment, the first area of ​​the carrier layer and the second area of ​​the wound contact layer are larger than an area of ​​the absorbent layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and related objects, features and advantages of the present disclosure will be more fully understood with reference to the following detailed description of more preferred (albeit exemplary) embodiments of the present invention, taken in conjunction with the accompanying drawings, in which:

[0028] Figure 1 is a schematic top view of a dressing according to an embodiment of the present disclosure;

[0029] Figure 2 is a schematic top view of a dressing according to other embodiments of the present disclosure;

[0030] Figure 3According to an embodiment of the present disclosure Figure 2 Cross-sectional view of the dressing;

[0031] Figure 4 is a cross-sectional view of an absorbent layer of a dressing according to one embodiment of the present disclosure;

[0032] Figure 5 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0033] Figure 6 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0034] Figure 6A is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0035] Figure 6B is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0036] Figure 7 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0037] Figure 7A is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0038] Figure 8 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0039] Figure 8A is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0040] Figure 9 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0041] Figure 9A is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure;

[0042] Figure 10 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure; and

[0043] Figure 11 is a cross-sectional view of an absorbent layer of a dressing according to another embodiment of the present disclosure. Embodiment

[0044] For example, Figure 1-Figure 3 FIG. 1 shows a wound care bandage or dressing 10 according to one embodiment of the present application. In an embodiment, the dressing 10 comprises a carrier layer 1 (e.g., see Figure 3), the carrier layer 1 is attached to the adhesive layer 2. In embodiments, the carrier layer 1 can be a top film. In embodiments, the carrier layer 1 can be opaque, partially or completely transparent, or translucent. In embodiments, the carrier layer 1 can be made of polyurethane. In embodiments, the carrier layer 1 can allow liquid in the bandage 10 to evaporate.

[0045] In an embodiment, Figure 3 As shown, the absorption / retention layer 3 can be fixed to the carrier layer 1 via the adhesive layer 2. In an embodiment, the absorption / retention layer 3 can be simply referred to as the absorption layer. In an embodiment, the absorption / retention layer 3 can absorb liquid exudate from the wound covered by the dressing 10. In an embodiment, the absorption / retention layer 3 can be provided above the wound contact layer 4, and when the dressing is in an appropriate position on the user's body, the wound contact layer 4 is suitable for contacting the user's skin. In an embodiment, as shown in FIG. Figure 2 As shown, for example, the wound contact layer 4 may be a perforated silicone gel layer that may include a large perforation 6 in a central portion that is generally located above the wound to allow liquid to flow from the wound into the absorbent / retention layer 3. Figure 1 and Figure 3 As shown, for example, the dressing 10 may include smaller perforations 7 around the circumference of the dressing 10 to improve adhesion to the user's skin around the wound. Figure 2 As shown, the dressing 10 may use perforations 6 instead of perforations 7. In an embodiment, a removable protective layer 5 (e.g., see FIG. 1 ) may be provided over the wound contact layer 4 before the dressing is applied to the user. Figure 3 In an embodiment, the protective layer 5 can be removed from the wound contact layer 4 in order to apply the dressing to the user's skin. Figure 4 A bandage or dressing 10 is shown which has both a large opening 6 and a small opening 7, but as shown in FIG. Figure 6 As shown, a cross-sectional view of the dressing 10 using only the opening 6 is shown. Figure 3 The cross-sectional view of the dressing 10 in FIG. 1 is the same, except that the opening 6 extends to the peripheral side of the wound contact layer 4 .

[0046] In an embodiment, the wound contact layer 4 may comprise a hydrogel or silicone gel, and the liquid absorption / retention layer 3 may comprise foam or highly absorbent fibers. In an embodiment, the liquid absorption / retention layer 3 may further comprise a retention layer intended to retain exudate and prevent it from flowing back into the wound site. Example 1

[0047] In an embodiment, Figure 1 、 Figure 2 、 Figure 3 and Figure 4As shown, for example, a dressing 10 includes a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 is disposed between the adhesive layer 2 and the wound contact layer 4, and the wound contact layer 4 may be a porous silicone gel layer. In an embodiment, as described above, the protective layer 5 may be removable.

[0048] In an embodiment, the areas of the wound contact layer 4 and the carrier layer 1 are larger than the area of ​​the absorption / retention layer 3, which allows the dressing to have a larger fitting area around the wound for more convenient application of the dressing.

[0049] In an embodiment, the protective layer 5 may be made of a polyethylene material, the carrier layer 1 may be made of a polyurethane material, and the adhesive layer 2 may be made of an acrylic adhesive.

[0050] In an embodiment, the wound contact layer 4 may be a silicone gel layer comprising perforations 6, which may be of uniform size. In this embodiment, the wound contact layer 4 does not comprise smaller openings 7, however in an embodiment smaller openings 7 may be used.

[0051] In an embodiment, Figure 4 As shown, for example, the absorbent / retention layer 3 may include two layers of polyurethane foam 3-1, to which superabsorbent polymer additive powder 3-2 is bonded via an adhesive / binder. In embodiments, the adhesive / binder enhances the bonding between the polyurethane foam and the superabsorbent polymer additive powder 3-2, thereby minimizing the superabsorbent polymer additive from shedding from the liquid absorbent / retention layer 3 after absorption of liquid, as well as during manufacture and use. In embodiments, a first layer of superabsorbent polymer additive powder 3-2 may be provided on the lower surface of the upper layer of foam 3-1, and a second layer may be provided on the upper surface of the lower foam layer. In embodiments, the polyurethane foam layer 3-1 may be made of medical-grade polyurethane foam, although other foam materials may also be used. In embodiments, the top surface of the upper first foam layer 3-1 may be connected to or otherwise positioned adjacent to the carrier layer 1, and when the bandage 10 is in place on the user's body, the lower polyurethane foam layer 3-1 may be positioned below the upper foam layer, closer to the user's skin. The lower polyurethane foam layer 3-1 can be connected and aligned with the wound contact layer 4, allowing exudate from the wound beneath the dressing 10 to flow into the absorbent layer 3 through the openings 6. The superabsorbent polymer additive enhances the absorption and retention of exudate. Example 2

[0052] In an embodiment, for example, Figure 1-Figure 3 and Figure 5As shown, the dressing 10 may include a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 may be provided between the adhesive layer 2 and the wound contact layer 4, and the wound contact layer 4 is a porous silicone gel layer. The protective layer 5 may be removable.

[0053] In an embodiment, as described above, the areas of the wound contact layer 4 and the carrier layer 1 are larger than the area of ​​the liquid absorption / retention layer 3 , so as to increase the conforming area of ​​the dressing 10 .

[0054] In an embodiment, the protective layer 5 may be made of polyethylene, the carrier layer 1 may be made of polyurethane, and the adhesive layer 2 may be made of acrylic adhesive. In an embodiment, the wound contact layer 4 may be silicone gel, with large perforations 6 and small perforations 7 provided therein.

[0055] from Figure 5 As can be seen, for example, the liquid absorption / retention layer 3 may include two layers of polyurethane foam 3-1, the surfaces of both layers of polyurethane foam 3-1 being coated with a super absorbent polymer additive layer 3-2, the super absorbent polymer additive layer 3-2 being bonded by an adhesive / binder to minimize shedding of the SAP additive after absorbing liquid. In an embodiment, the four edges of the two foam layers 3-1 may be heated and joined together using ultrasonic welding to form a chamber between the foam layers 3-1, for example, to prevent the super absorbent polymer additive from leaking from the liquid absorption / retention layer 3 after absorbing liquid or during manufacturing or use. In an embodiment, the foam layer 3-1 may be made of similar materials and in a similar manner to those discussed above. Figure 4 Positioned in a similar manner. Example 3

[0056] In an embodiment, Figure 1-Figure 3 and Figure 6 As shown, for example, a high liquid absorption wound care dressing 10 may include a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. As described above, in the embodiment, the liquid absorption / retention layer 3 is disposed between the adhesive layer 2 and the wound contact layer 4, and the wound contact layer 4 is a porous silicone gel layer, and the protective layer 5 is removably connected to the wound contact layer 4.

[0057] In an embodiment, as described above, the areas of the wound contact layer 4 and the carrier layer 1 are larger than the area of ​​the liquid-absorbing layer 3. In an embodiment, the protective layer 5 is made of a release paper material coated with silicone, the carrier layer 1 is made of a non-woven fabric material, and the adhesive layer 2 is made of an acrylic adhesive.

[0058] In an embodiment, as generally described above, the wound contact layer 4 may be made of a silicone rubber material, and the perforations 6 of the same size may be provided on the silicone gel layer.

[0059] from Figure 6 As can be seen, for example, similar to the above reference Figure 4 and Figure 5 As discussed, the liquid absorption / retention layer 3 can be made of two layers of polyurethane foam 3-1. In an embodiment, the surfaces of the polyurethane foam layers 3-1 facing each other can be coated with a superabsorbent polymer additive layer 3-4 applied in an aqueous solution. The superabsorbent polymer additive layer 3-4 can include an adhesive / binder to minimize shedding of the superabsorbent polymer additive when liquid is absorbed.

[0060] In an embodiment, the four edges of the two layers of foam 3-1 can be heated and ultrasonically welded together to form a chamber between the two layers of foam and to form a chamber similar to the above reference Figure 5 The discussed approach further minimizes shedding of superabsorbent polymer additives. Example 4

[0061] In an embodiment, Figure 1-Figure 3 and Figure 6A As shown, for example, a liquid-absorbing wound care dressing 10 includes a carrier layer 1, an adhesive layer 2, a liquid-absorbing / retaining layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid-absorbing layer 3 is disposed between the adhesive layer 2 and the wound contact layer 4, and the wound contact layer 4 is a porous silicone gel layer. As described above, the protective layer 5 may be removable.

[0062] In an embodiment, the areas of the wound contact layer 4 and the carrier layer 1 are larger than the area of ​​the liquid absorption layer 3. In an embodiment, the protective layer 5 may be made of a release paper material coated with silicone, the carrier layer 1 may be made of a non-woven fabric material, and the adhesive layer 2 may be or include an acrylic adhesive.

[0063] In an embodiment, the wound contact layer 4 may be made of a silicone rubber material, and the silicone gel layer may be provided with perforations 6 of the same size.

[0064] In an embodiment, from Figure 6A As can be seen in FIG. 3 , for example, the liquid absorption / retention layer 3 can be made of two layers of polyurethane foam 3-1. In an embodiment, the surface of one polyurethane foam layer 3-1 facing the other polyurethane foam layer 3-1 (i.e., Figure 6AThe lower surface of the middle upper layer 3-1 may be coated with a superabsorbent polymer additive powder layer 3-2. In an embodiment, the lower foam layer 3-1 may not include the superabsorbent polymer powder layer 3-2 or 3-4. In an embodiment, the lower foam layer 3-1 may include the superabsorbent polymer additive layer 3-2, while the upper foam layer may not include any superabsorbent polymer additive.

[0065] In an embodiment, for example, Figure 6B As seen in FIG, superabsorbent polymer additive powder can be applied to the foam layer 3-1 via an aqueous / solvent-based coating 3-4. In addition to this, Figure 6B Dressing 10 with Figure 6A The dressing 10 is the same as in the embodiment of the present invention, except that no superabsorbent polymer is provided on the lower foam layer 3-1. Example 5

[0066] In an embodiment, Figure 1-Figure 3 and Figure 7 As shown, for example, a high liquid absorption wound care dressing 10 may include a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 is disposed between the adhesive layer 2 and the wound contact layer 4, and as described above, the wound contact layer 4 is a porous silicone gel layer that is removably covered by the protective layer 5.

[0067] In an embodiment, the area of ​​the wound contact layer 4 and the carrier layer 1 is larger than the area of ​​the liquid absorption layer 3. In an embodiment, the protective layer 5 can be made of a release paper material coated with silicone, the carrier layer 1 can be made of a non-woven fabric material, and the adhesive layer 2 can be made of an acrylic adhesive. In an embodiment, as Figure 7 As shown, the wound contact layer 4 may be a silicone gel layer comprising perforations 6 and smaller perforations 7 .

[0068] In an embodiment, from Figure 7 As can be seen in the figure, for example, the liquid absorption / retention layer 3 can include a polyurethane foam layer 3-1 and multiple hydrophilic nonwoven fabric layers 3-5. In an embodiment, the polyurethane foam layer 3-1 can be combined with a superabsorbent polymer additive layer 3-2 provided in powder form. In an embodiment, the polyurethane foam layer 3-1 and the nonwoven fabric layer 3-5 can be thermally bonded together to prevent the superabsorbent polymer additive from leaking from the liquid absorption / retention layer 3 after absorbing liquid. In an embodiment, the superabsorbent polymer additive layer 3-2 can be provided as a powder impregnated into the foam.

[0069] In an embodiment, for example, Figure 7A As seen in Figures 3 and 4, the superabsorbent polymer additive can be provided as part of an aqueous / solvent-based coating 3-4 rather than in powder form. Figure 7AThe dressing 10 is otherwise similar to Figure 7 Same dressing as shown in . Example 6

[0070] In an embodiment, Figure 1-Figure 3 and Figure 8 As shown, a high liquid absorption wound care dressing 10 may include a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 may be disposed between the adhesive layer 2 and the wound contact layer 4, the wound contact layer 4 may be a porous silicone gel layer, and the protective layer 5 may be removable.

[0071] In an embodiment, the areas of the wound contact layer 4 and the carrier layer 1 may be larger than the area of ​​the liquid-absorbing layer 3. In an embodiment, the protective layer 5 may be made of a release paper material coated with silicone, the carrier layer 1 may be made of a polyurethane film, and the adhesive layer 2 may be made of an acrylic adhesive. In an embodiment, the wound contact layer 4 may be a silicone gel layer, and the wound contact layer 4 may be provided with perforations 6 of the same size.

[0072] In an embodiment, for example, Figure 8 In the embodiment, the liquid absorption / retention layer 3 may be composed of two polyurethane foam layers 3-1 and a plurality of hydrophilic non-woven fabric layers 3-5. In an embodiment, the polyurethane foam layer 3-1 may be combined with a superabsorbent polymer additive powder layer 3-2 provided on the upper surface of the upper foam layer 3-1 and the lower surface of the lower foam layer 3-1. In an embodiment, the polyurethane foam layer 3-1 and the non-woven fabric layer 3-5 may be thermally bonded together to prevent the superabsorbent polymer additive from leaking from the liquid absorption / retention layer 3 after absorbing liquid.

[0073] In an embodiment, Figure 8A As shown, for example, the polyurethane foam layer 3-1 can be combined with a superabsorbent polymer additive layer 3-4 provided via an aqueous solution / liquid. Figure 8A Dressing 10 with reference Figure 8 The dressing is the same as described. Example 7

[0074] In an embodiment, Figure 1-Figure 3 and Figure 9 As shown, a high liquid absorption wound care dressing 10 includes a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 may be disposed between the adhesive layer 2 and the wound contact layer 4, and the wound contact layer 4 is a porous silicone gel layer, and the protective layer 5 is removably connected to the wound contact layer 4.

[0075] In an embodiment, the wound contact layer 4 and the carrier layer 1 have an area greater than that of the liquid absorption / retention layer 3. In an embodiment, the protective layer 5 can be made of a release paper material coated with silicone, the carrier layer 1 can be made of a polyurethane film, and the adhesive layer 2 can be made of an acrylic adhesive. In an embodiment, the wound contact layer 4 can be a silicone gel layer with perforations 6 of the same size provided therein.

[0076] In an embodiment, Figure 9 As shown, the liquid absorption / retention layer 3 may be composed of two polyurethane foam layers 3-1 and one hydrophilic nonwoven fabric layer 3-5. In an embodiment, the hydrophilic nonwoven fabric layer 3-5 may be bonded to the surface of the polyurethane foam layer 3-1 facing the carrier layer 1. In an embodiment, the polyurethane foam layer 3-1 may be combined with a superabsorbent polymer additive powder layer 3-2, which may be provided on the upper surface of the upper foam layer 3-1 and the lower surface of the lower foam layer. In an embodiment, the polyurethane foam layer 3-1 may be thermally bonded to the nonwoven fabric layer 3-5 to prevent the superabsorbent polymer additive from leaking from the liquid absorption / retention layer after absorbing liquid.

[0077] In an embodiment, Figure 9A As shown, the polyurethane foam layer 3-1 can be combined with a superabsorbent polymer additive layer 3-4 provided via an aqueous liquid. Figure 9A The embodiments and the above reference Figure 9 The described embodiments are identical. Example 7

[0078] In an embodiment, Figure 1-Figure 3 and Figure 10 As shown, a high liquid absorption wound care dressing 10 may include a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 may be disposed between the adhesive layer 2 and the wound contact layer 4, and the wound contact layer 4 may be a porous silicone gel layer. In an embodiment, the protective layer 5 may be removable.

[0079] In an embodiment, the wound contact layer 4 and the carrier layer 1 have an area greater than that of the liquid absorption / retention layer 3. In an embodiment, the protective layer 5 can be made of a release paper material coated with silicone, the carrier layer 1 can be made of a polyurethane film, and the adhesive layer 2 can be made of an acrylic adhesive. In an embodiment, the wound contact layer 4 can be a silicone gel layer with perforations 6 of the same size provided therein.

[0080] In an embodiment, from Figure 10As can be seen, for example, the liquid absorption / retention layer 3 can be composed of two polyurethane foam layers 3-1. In an embodiment, the facing surfaces of each polyurethane foam layer 3-1 can be coated with an aqueous / solvent-based superabsorbent polymer additive layer 3-4. In an embodiment, the aqueous / solvent solution on the foam layer 3-1 can be dried, and then the foam can be subjected to a secondary surface treatment using a powder-based treatment with a superabsorbent polymer additive powder layer 3-2. In an embodiment, the four edges of the two polyurethane foam layers 3-1 can be joined by ultrasonic sealing, thereby forming a chamber between the two foam layers 3-1 to prevent the superabsorbent additive from leaking from the liquid absorption / retention layer 3 after absorbing liquid. Example 8

[0081] from Figure 1-Figure 3 and Figure 11 As can be seen in FIG, a high liquid absorption wound care dressing 10 comprises a carrier layer 1, an adhesive layer 2, a liquid absorption / retention layer 3, a wound contact layer 4, and a protective layer 5. In an embodiment, the liquid absorption / retention layer 3 may be disposed between the adhesive layer 2 and the wound contact layer 4, wherein the wound contact layer 4 may be a porous silicone gel layer, and the protective layer 5 may be removable.

[0082] In an embodiment, the areas of the wound contact layer 4 and the carrier layer 1 are larger than the area of ​​the liquid-absorbing layer 3. In an embodiment, the protective layer 5 can be made of a release paper material coated with silicone, the carrier layer 1 can be made of a polyurethane film, and the adhesive layer 2 can be made of an acrylic adhesive. In an embodiment, the wound contact layer 4 can be a silicone gel layer with perforations 6 of the same size provided therein.

[0083] In an embodiment, Figure 11 As shown, the liquid absorption / retention layer 3 may include two polyurethane foam layers 3-1. In embodiments, both surfaces of the polyurethane foam layer 3-1, spaced apart from the wound contact layer 4, may be coated with an aqueous / solvent-based superabsorbent polymer additive layer 3-4. In embodiments, the bottom surface of the upper polyurethane foam layer 3-1, which is closer to the wound contact layer 4, and the top surface of the lower polyurethane foam layer 3-1 may be coated with an aqueous / solvent-based superabsorbent polymer additive layer 3-4. In embodiments, the two polyurethane foam layers 3-1 may be combined with a superabsorbent polymer additive powder layer 3-2 using a powder-based treatment on the surfaces facing each other. In embodiments, the four edges of the two polyurethane foam layers 3-1 may be joined by ultrasonic welding to form a chamber between the two polyurethane foam layers, thereby preventing the superabsorbent polymer additive from leaking from the liquid absorption / retention layer 3 after absorbing liquid.

[0084] In each of the embodiments discussed herein, exudate and moisture from the wound can be absorbed in the absorption / retention layer 3. In particular, the exudate and moisture will pass through the foam layer 3-1 and enter the superabsorbent polymer additive layers 3-2, 3-4. As the superabsorbent polymer absorbs the exudate, it may swell slightly and provide a gel consistency. In embodiments, this gel consistency allows the absorption / retention layer 3 to maintain flexibility and provide cushioning together with the foam layer 3-1, thereby improving user comfort. In embodiments, the use of superabsorbent polymer additives generally allows for the absorption of large amounts of moisture, typically more than other absorbent materials. In embodiments, the absorbency can be measured according to BS EN 13726-1 method and can be as low as 0.05 g / cm 2 Up to 3g / cm 2 However, more or less absorbency may be provided.

[0085] In an embodiment, as described above, the wound contact layer 4 may be a porous silicone gel layer. In an embodiment, the wound contact layer 4 may be a transparent polyurethane film, provided with a silicone-based adhesive on at least its bottom surface to secure the bandage or dressing 10 to the user's skin. In an embodiment, the wound contact layer 4 may be adhered to the absorbent / retention layer 3, or more specifically, to the lower foam layer 3-1.

[0086] In embodiments, the silicone adhesive or silicone gel of the wound contact layer 4 adheres to the user's skin surrounding the wound while avoiding strong adhesion to the wound. In embodiments, the wound contact layer 4 may include a plurality of perforations 6, 7 formed therethrough. In embodiments, the perforations 6, 7 allow exudate from the wound to flow through the wound contact layer 4 into the absorbent / retention layer 3, specifically through the lower foam layer 3-1 and into the superabsorbent polymer additive layers 3-2, 3-4, where it is absorbed. In embodiments, the perforations 6, 7 may have different shapes and sizes. For example, smaller perforations 7 may be provided at the periphery of the bandage 10 to promote good adhesion to the user's skin surrounding the wound, while larger perforations 6 may be provided in the center above the wound to absorb more exudate.

[0087] In embodiments, other materials may be used to form wound contact layer 4, but the adhesive facing the user's skin must be silicone-based. In embodiments, any adhesive suitable for contact with the user's skin may be used, including, by way of example only, medical silicone adhesives, medical acrylic adhesives, and medical hydrocolloid adhesives. In embodiments, perforations 6 allow exudate to pass through the perforations and into absorbent / retaining layer 3. Wound contact layer 4 provides a stable, secure connection to the user's skin, thereby maintaining bandage 10 in place with relative comfort. Furthermore, the silicone adhesive allows for relatively easy removal of the bandage without damaging the wound.

[0088] In an embodiment, a packaging element (not shown) is provided for storing bandage or dressing 10 before use. In an embodiment, packaging element can be made by a combination of paper and polyethylene or made by paper, and forms a pouch or a pocket that can store bandage 10. In an embodiment, packaging element can be made by any other suitable durable material. In an embodiment, packaging element can be made by a material that is suitable for sterilizing bandage 10 in packaging element. In an embodiment, packaging element can be made by a watertight material. In an embodiment, packaging element can be made by a material that allows liquid to flow out but not enter, or allows liquid to enter but not flow out. In an embodiment, packaging element can be transparent or include a transparent portion. In an embodiment, packaging element can include a top and a bottom, with bandage 10 (comprising each layer discussed above) sandwiched between the top and the bottom.

[0089] In some embodiments, the use of a superabsorbent polymer additive between the lower foam layer and the upper foam layer 3-1, or elsewhere, can form a gel pad when absorbing exudate. This gel consistency increases patient comfort and maximizes the bandage's flexibility, allowing for a more conformable bandage and reducing the likelihood of the bandage or dressing 10 separating from the user's skin. In some embodiments, the use of superabsorbent polymer additive layers 3-2 and 3-4 can increase absorption capacity while generally reducing odor as exudate is absorbed into the gel. Furthermore, the gel consistency of superabsorbent polymer additive layers 3-2 and 3-4 can improve pressure distribution when the bandage 10 is subjected to stress.

[0090] The bandage or dressing 10 can be prepared by impregnating the polyurethane foam layer 3-1 with the superabsorbent polymer additive powder and the binder powder described above. In the Examples, samples were evaluated to determine the ability of the superabsorbent polymer additive powder and the binder powder to maintain adhesion to the base material after slight agitation, the purpose of which was to simulate the post-impregnation manufacturing process, shipping / handling of the dressing, and / or use of the final finished bandage.

[0091] In embodiments, the impregnation process for impregnating the superabsorbent polymer additive powder and binder powder into the polyurethane foam layer 3-1 can be modified by adjusting parameters (e.g., the magnitude of the AC electric field), thereby allowing the superabsorbent polymer additive and binder powder additive to penetrate deeper into the foam matrix of the foam, thereby allowing for the application of a larger amount of additive. In embodiments, the top and bottom surfaces of at least one foam layer 3-1 can be coated to increase the SAP / binder powder coating concentration. In embodiments, the superabsorbent polymer additive powder and binder powder can be impregnated into the foam layer 3-1 using any suitable process.

[0092] In the Examples, two wound exudate management properties can be examined: Free-Swelling Absorbent Capacity (FAC) and Fluid Retention Under Compression (FRUC). Free-Swelling Absorbent Capacity (FAC) assesses the maximum absorbency a dressing material can achieve when exposed to excessive amounts of simulated wound exudate in an in vitro environment. FRUC, on the other hand, is an in vitro assessment of the amount of fluid a wound dressing material can "lock up" under the same compression levels commonly used in venous leg ulcer bandages. Fluid retention is important because it measures the ability of a dressing material to prevent leakage and fluid accumulation, which can lead to adverse consequences for wound healing. By evaluating the absorbent capacity and fluid retention properties of each test article in vitro, it is possible to assess how each article will handle wound exudate.

[0093] 2.5 mm EX polyurethane foam can be prepared to include different dry coating weights of superabsorbent polymer (SAP) powder and binder powder to provide different test products. In the examples, SAP powder and binder powder can be applied to the EX foam in four different ratios: (1) 80% SAP and 20% binder; (2) 90% SAP and 10% binder; (3) 95% SAP and 5% binder; and (4) 100% SAP and 0% binder. In the examples, an untreated 2.5 mm EX foam material can be prepared as a negative control. Table 1 provides more information about the test products and controls:

[0094] In the examples, 5 cm x 5 cm samples can be cut from the center area of ​​the polyurethane EX foam to provide each test product and control product. These samples are used for both the non-swelling absorption capacity test and the subsequent liquid retention under compression test. In the examples, other sample sizes can also be used.

[0095] In an embodiment, a drop test can be performed to evaluate the ability of one or more powder additives to remain attached / fixed to the polyurethane EX foam after the powder impregnation process and subsequent heat treatment. In an embodiment, during the drop test, the test sample is attached to the arm of a "wrist-actuated" vibrator to provide rapid back-and-forth vibrations to remove any unbound or loosely bound powder additives. The test sample is vibrated for 30 seconds. The weight of each test sample before and after the test can be recorded and compared to determine the amount of powder loss. In an embodiment, other drop tests can also be used.

[0096] In the examples, to assess the ability of different test articles to absorb fluid from mild to heavily exuding wounds, a protocol based on BS EN 13726-1:2002 section 3.2 may be used [1]. Briefly, wound exudate may be simulated by an aqueous test solution (test solution A) containing 142 mmol sodium and 2.5 mmol calcium as chloride salts. The ionic composition of this solution is comparable to that of wound exudate. In the examples, other simulated wound exudates may also be used. A portion of the test article of size 5 cm x 5 cm may be cut and measured to the nearest 0.1 cm to determine the exact sample area (A) and weighed in a dry state to determine the first mass (M0). In the examples, other sample sizes may also be used. In the examples, the test article may be placed in a culture dish and completely immersed in a test solution preheated to 37°C ± 1°C, the volume of which is equivalent to 40 times the mass of the sample being tested. The test article in the culture dish may be transferred to an incubator and immersed at a temperature of 37°C ± 1°C for 30 minutes ± 1 minute. At the end of the incubation period, each sample was removed from the test solution by gripping the corner or end of the sample with self-stretching tweezers, and the excess liquid was allowed to drip for 30 seconds ± 5 seconds. The sample was then reweighed to obtain a second mass (M t In an embodiment, the absorption amount may be expressed as per 100 cm 2 The mass of solution absorbed is calculated as follows: In an embodiment, a total of three replicates of each test article may be tested. In an embodiment, the average absorption value and related statistical data for each test article may be recorded. In an embodiment, other protocols or tests may also be used.

[0097] To assess the ability of the test article to retain fluid under pressure, a custom test can be performed based on the procedures proposed by Debashsish et al. and Foster et al. [2], [3], although other procedures may also be used. Following the non-swelling test, each test article can be placed with the patient contact surface (lower layer) facing downwards on a polypropylene perforated surface suspended above a container that collects any fluid released by the test article sample during the test. A 7 cm x 7 cm Perspex pressure plate can be placed on the test article sample. The Perspex pressure plate is used to ensure uniform pressure distribution across the sample. A pressure equivalent to the recommended compression force (40 mm Hg) for venous leg ulcer compression dressings is applied to the test article using weights totaling 1350 g. After 1 minute of compression, the assembly consisting of the weights, Perspex pressure plate, test article and PP perforated surface can be disassembled and the test article sample reweighed to obtain the third mass (M r ). Liquid retention can be expressed as per 100cm2 The retained solution mass is calculated as follows: In addition, by comparing the fluid retention after compression (M r ) and absorption (M t ) ratio, the percentage of liquid retention can be calculated.

[0098] In the examples, a total of three replicates of each test article were tested. The average absorbance values ​​and related statistical data for each test article can be reported as shown in the following table.

[0099] Table 2 below summarizes the fixation / detachment test data for the four test products: Table 2: Summary of immobilization test data for negative control and test articles.

[0100] Tables 3, 4, 5, 6, and 7 below summarize the test data for the non-swelling absorbency and liquid retention tests conducted on the negative control and all four test articles. Additionally, Table 8 provides a summary of the mean absorbency, liquid retention, and percent change in mean absorbency relative to the negative control. Table 3: Non-swelling Absorption and Liquid Retention of Controls Table 4: Non-swelling absorption and liquid retention of Test 1 (80% SAP, 20% binder) Table 5: Non-swelling absorption and liquid retention of Test 2 (90% SAP, 10% binder) Table 6: Non-swelling absorption and liquid retention of Test 3 (95% SAP, 5% binder) Table 7: Non-swelling absorption and liquid retention of Test 4 (100% SAP, 0% binder) Table 8: Summary of Liquid Handling Performance

[0101] In summary, the use of some binder powder can improve the adhesion / fixation of the superabsorbent polymer powder to the base material, however, it is not necessary to provide binder powder in the bandage or dressing 10 discussed herein. In the fixation / detachment test, the prototype material (Test 4) without any binder powder showed a loss of 37.6% of the SAP powder. This loss was 15-28 times the powder loss of other materials that contained some degree of binder powder. However, the concentration of binder powder may vary. In the fixation / detachment test, all the tests containing binder powder had a low powder loss (1.3-2.4%). This may indicate that only a small amount (≤5%) of binder powder concentration is required to effectively bond the SAP powder to the polyurethane foam substrate evaluated in this study. In embodiments, other percentages of binder powder (including 0%) may be used.

[0102] As the binder powder concentration increases, the hardness or stiffness of the treated material also tends to increase, however this property can be further assessed by measuring the flexural stiffness / bending compliance of the material, for example, according to the EN 1644-2 standard.

[0103] During the FAC test, the concentration of binder powder appeared to be negatively correlated with the material's absorption (i.e., as the binder powder concentration increased, the material's absorption decreased). For example, Test 2 (90% SAP / 10% binder) and Test 3 (95% SAP / 5% binder) had similar SAP concentrations, calculated as 432 gsm and 419 gsm, respectively (see Table 1), and therefore should have exhibited similar absorption values. However, Test 3 consistently exhibited an increase in absorption of >13.7% compared to Test 2. In embodiments, the binder powder may melt and encapsulate the SAP powder particles, thereby reducing absorption. The melting point of the binder powder (PEG 8000PF) was approximately 55-60°C [4], and the heat treatment process used to impregnate the powder into the polyurethane was performed at 100°C for 30 seconds. Higher concentrations of binder powder may have caused the binder powder to melt and completely encapsulate or encapsulate more of the SAP powder particles in the PEG layer. This PEG coating may reduce the uptake of the affected SAP particles, leading to an overall decrease in uptake of the treated materials with increasing binder powder concentration.

[0104] Regarding the FRUC test, the presence of superabsorbent polymer and / or binder powder appears to improve liquid retention values. All tested materials showed high liquid retention percentage values ​​(i.e., ≥92.7%), with superabsorbent polymer additive-impregnated materials showing retention values ​​of 93.7%-97.4%.

[0105] In summary, combining the tests described above, it seems reasonable to draw the following conclusions: 1. The use of binder powder can prevent excessive loss of superabsorbent polymer additive powder during the powder impregnation process; 2. Increasing the concentration of binder powder appears to have a negative impact on the hardness or stiffness of the treated material; 3. As the ratio of binder powder to superabsorbent polymer additive powder increases, the absorbent capacity of the treated material decreases; 4. The presence of superabsorbent polymer additives and / or binder powders can increase fluid retention values.

[0106] In the embodiment, as described above, although the use of an adhesive can improve the adhesion of the superabsorbent polymer additive to the foam layer 3-1, the use of an adhesive is not necessarily required.

[0107] Although the present invention has been described with respect to its specific embodiments, many other changes and modifications and other uses will be apparent to those skilled in the art. Therefore, it is preferred that the present invention not be limited to the specific disclosure herein. References (1)BS EN 13726-1:2002,Test Methods for Primary Wound Dressings.Part1:Aspects of Absorbency.BSI,2002. (2)Mennini, N., Greco, A., Bellingeri, A., De Vita, F., & Petrella, F. (2016). Quality of wound dressings: a first step in establishing shared criteria and objective procedures to evaluate their performance. Journal of wound care, 25(8), 428–437. https: / / doi.org / 10.12968 / jowc.2016.25.8.428 (3)Debashish,C.,Roman,M.(2015).In Vitro Comparison of the Absorptionand Retention Capabilities of Two Superabsorbent Wicking Dressings.Posterpresented at the meeting of Wound,Ostomy,and Continence Nurses Society,SanAntonio,TX. (4)Carbowax TM PEG 8000(Powder),Fisher Chemical TM ;ThermoFisherScientific:Fair Lawn,NJ,August 31,2023. https: / / www.fishersci.com / shop / products / carbowax-peg-8000-powder- fisher-chemical-2 / P156500 (Accessed August 31,2023)。

Claims

1. A medical dressing comprising: carrier layer; an adhesive layer, which is provided below the carrier layer and close to the user's skin when the medical dressing is placed in an appropriate position on the user; an absorption layer, the absorption layer being located below the adhesive layer and being connected to the carrier layer via the adhesive layer, The absorbent layer is configured to absorb and retain exudates, and the absorbent layer includes at least one foam layer having a superabsorbent polymer additive provided thereon; as well as a wound contact layer located beneath the absorbent layer and configured to adhere to the skin of a user, The wound contact layer comprises a plurality of openings through which the exudate can flow into the absorbent layer.

2. The medical dressing according to claim 1, wherein the absorbent layer comprises: a first polyurethane foam layer comprising at least a first layer of a superabsorbent polymer additive; as well as a second polyurethane foam layer comprising at least a second layer of a superabsorbent polymer additive, wherein the exudate is absorbed by at least one of the first layer of super absorbent polymer additives and the second layer of super absorbent polymer additives.

3. The medical dressing according to claim 2, wherein at least one of the first layer of superabsorbent polymer additives and the second layer of superabsorbent polymer additives comprises a binder powder, the binder powder being configured to fix the superabsorbent polymer additives to the first polyurethane foam layer or the second polyurethane foam layer, respectively.

4. The medical dressing according to claim 2, wherein the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive are provided in the form of powder and are impregnated into the first polyurethane foam layer and the second polyurethane foam layer, respectively.

5. The medical dressing of claim 4, wherein at least one of the first layer of superabsorbent polymer additives and the second layer of superabsorbent polymer additives comprises superabsorbent polymer additives provided via an aqueous solution.

6. The medical dressing of claim 4, wherein the first layer of superabsorbent polymer additives and the second layer of superabsorbent polymer additives comprise superabsorbent polymer additives provided via an aqueous solution.

7. The medical dressing of claim 2, wherein the first layer of superabsorbent polymer additive and the second layer of superabsorbent polymer additive are provided via aqueous solutions applied to the first polyurethane foam layer and the second polyurethane foam layer, respectively.

8. The medical dressing according to claim 2, wherein the absorbent layer further comprises a third layer of a superabsorbent polymer additive provided on at least one of the first polyurethane foam layer and the second polyurethane absorbent layer.

9. The medical dressing according to claim 8, wherein the third layer of superabsorbent polymer additive is a powder.

10. The medical dressing according to claim 8, wherein the third layer of superabsorbent polymer additive is provided via an aqueous solution.

11. The medical dressing of claim 2, wherein respective edges of the first polyurethane foam layer and the second polyurethane foam layer are sealed together to form a chamber to secure the superabsorbent polymer additive in place.

12. The medical dressing of claim 11, wherein the respective edges are sealed via ultrasonic welding.

13. The medical dressing according to claim 1, further comprising a hydrophilic nonwoven fabric bonded together with at least one of the first polyurethane foam layer and the second polyurethane foam layer over the superabsorbent polymer additive.

14. The medical dressing of claim 1, wherein the superabsorbent polymer additive is a powder impregnated in the at least one foam layer.

15. The medical dressing of claim 1, wherein the superabsorbent polymer additive is provided via an aqueous solution.

16. The medical dressing of claim 15, wherein the superabsorbent polymer additive remains on the at least one polyurethane foam layer after liquid of the aqueous solution evaporates.

17. The medical dressing according to claim 1, wherein the carrier layer is a polyurethane film.

18. The medical dressing of claim 1, wherein the plurality of openings formed in the wound contact layer are of the same size.

19. The medical dressing of claim 1 , wherein the plurality of openings formed in the wound contact layer comprises a first set of larger openings located at the center of the dressing over the wound when the dressing is on the user's skin, and a second set of smaller openings located at the periphery of the dressing.

20. The medical dressing of claim 1, wherein the first area of ​​the carrier layer and the second area of ​​the wound contact layer are larger than the third area of ​​the absorbent layer.

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