Wound Dressing

Abstract

The present invention relates to a wound dressing comprising or consisting of: (a) a covering layer; (b) a sheath on the wound-facing side of the covering layer, (c) an absorbent core within the sheath, and (d) an adhesive layer on the wound-facing side of the sheath; wherein the sheath comprises (b1) an adhesive sheath layer, (b2) a proximal sheath layer on the proximal side of the absorbent core and the adhesive sheath layer, and (b3) a distal sheath layer on the distal side of the absorbent core and the adhesive sheath layer; wherein the adhesive layer comprises an opening, and wherein the adhesive layer has: (i) a proximal side facing the wound suitable for adhering to a body part, and (ii) a distal side adhered to the outer periphery of the covering layer.

Description

Technical Field

[0001] The present disclosure relates to an absorbent dressing for attachment to a body part and for treating skin wounds, particularly wounds exhibiting heavy exudation. Background Art

[0002] When skin or other tissues are injured, wounds usually begin to emit exudate. Exudate includes liquid that seeps from blood or lymphatic vessels, and may contain serum, fibrin and leukocytes. Wounds in areas containing strong infections or inflammations may exude a large amount of fluid. In order to control these large amounts of fluid, wounds are usually covered with wound dressings, which include absorbent cores that can absorb a large amount of fluid. Thus, fluid can be removed from the wound while keeping the wound moist, thus promoting wound healing.

[0003] These absorbent cores may comprise superabsorbent particles such as those described in EP 1 985 270 A2. Some superabsorbents can bind up to 1000 times their own weight in a fluid. Wound dressings containing superabsorbents are therefore particularly effective. However, when absorbing liquid, the superabsorbent particles and therefore the absorbent core increase significantly in volume. Therefore, special attention needs to be paid to the design of the wound dressing so that it can accommodate the absorbent core despite its increased volume.

[0004] In the past, it has been suggested to use an elastic cover to accommodate the increased volume while keeping the wound dressing attached to the wound. As the volume of the absorbent core increases, the cover is stretched and expands with the absorbent core. Alternatively or additionally, the absorbent core in the dressing may be replaceable. Some dressings provide additional space for the absorbent core to expand by wrapping the core in a larger sheath.

[0005] Despite these improvements, the structural integrity of dressings for highly exuding wounds can be compromised by the dramatic increase in volume, leading to delamination of the individual dressing layers. Additionally, stretching of the cover layer during expansion can lead to a loss of adhesive strength.

[0006] Therefore, there is a need in the art for improved absorbent wound dressings that can absorb large amounts of exudate while adhering to the area surrounding the wound site. Summary of the invention

[0007] This problem is solved by an absorbent dressing as described in the appended claims. The dressing is sealed in a particularly secure manner and provides sufficient space within the dressing for the absorbent core to expand when absorbing fluid. The disadvantages of the dressings known in the art are thereby overcome.

[0008] In a first aspect, the present invention relates to a wound dressing comprising or consisting of: (a) a covering layer; (b) a sheath on the wound-facing side of the covering layer, (c) an absorbent core within the sheath, and (d) an adhesive layer on the wound-facing side of the sheath; wherein the sheath comprises (b1) an adhesive sheath layer, (b2) a proximal sheath layer on the proximal side of the absorbent core and the adhesive sheath layer, and (b3) a distal sheath layer on the distal side of the absorbent core and the adhesive sheath layer; wherein the adhesive layer comprises an opening, and wherein the adhesive layer has (i) a proximal side facing the wound suitable for adhering to a body part, and (ii) a distal side adhered to the outer periphery of the covering layer.

[0009] A wound dressing is a medical dressing that is capable of absorbing fluids, such as wound fluids. It is therefore an absorbent dressing. The wound dressing may be adapted for application to skin, such as human skin, and thus adheres to the skin of the wearer, such as the skin of a patient.

[0010] Preferably, the wound dressing of the present invention is a one-piece dressing. This means that the medical staff applying the dressing does not have to assemble the dressing from several parts before applying the dressing. Instead, all parts of the wound dressing described herein form a unit that is held together without the use of further parts or supporting means.

[0011] The wound dressing comprises (b) a sheath on a wound-facing side of a cover layer, the wound-facing side of the cover layer being the proximal side of the cover layer. As used herein, the terms "proximal" and "distal" refer to the position of the respective surfaces relative to a wearer when the wound dressing is worn. According to the standard meaning of the terms in the art, "distal" refers to a surface further from the wearer, and "proximal" refers to a surface closer to the wearer, i.e., a surface closer to the wound, skin, and / or other body surface.

[0012] The sheath is a closed body, enclosing an inner sheath space. In the inner sheath space, an absorbent core is arranged. The inner sheath space is completely surrounded by the proximal and distal sheath layers. As described below, the sheath can be closed by sealing the outer edges of at least the proximal and distal layers of the sheath, preferably by sealing the outer edges of the proximal and distal sheath layers and the outer edge of the adhesive sheath layer. In a preferred embodiment, the outer edges of the proximal and distal sheath layers are sealed together with the adhesive sheath layer arranged between them.

[0013] Thus, the sheath comprises (b1) an adhesive sheath layer, (b2) a proximal sheath layer on the proximal side of the absorbent core and the adhesive sheath layer and (b3) a distal sheath layer on the distal side of the absorbent core and the adhesive sheath layer. The sheath may consist of the above-mentioned layers, i.e. the adhesive sheath layer, and the proximal and distal sheath layers. However, further layers may also be added to the sheath, for example to increase the absorbent capacity and / or structural integrity of the sheath.

[0014] The adhesive sheath layer included in the sheath is suitable for connecting the proximal and distal sheath layers to each other, particularly the outer edge of the proximal and distal sheath layers. For this reason, at least the part of the adhesive sheath layer can be arranged between the outer edge of the proximal and distal sheath layers. The outer edge (outer periphery) of this three-layer is preferably sealed to each other around the whole periphery of the sheath. Like this, it is guaranteed that the absorbent core is firmly maintained in the closed sheath. Therefore, in a preferred embodiment, the outer edge of the adhesive sheath layer, the proximal sheath layer and the distal sheath layer is connected to form the sheath by sealing (preferably heat sealing). This " periphery " is located on a plane substantially parallel to the adhesive layer, for example the mid-plane of the sheath.

[0015] The adhesive sheath layer can be substantially the same shape and size as the proximal and / or distal sheath layers. For example, all three layers can have a rectangular shape with rounded corners. Alternatively, all three layers can have a circular, ellipsoidal or identical irregular shape. The adhesive sheath layer with this shape and size can have - but not necessarily have - an opening in the middle thereof. The opening in the adhesive sheath layer and the absorbent core can have substantially the same shape, such as a rectangular, circular, elliptical or identical irregular shape. Preferred shapes include rectangular shapes with rounded edges. The opening in the adhesive sheath layer helps regulate the flow of wound fluid from the sheath layer (particularly the proximal sheath layer) to the absorbent core.

[0016] In some preferred embodiments, the adhesive sheath layer does not have an opening in the middle thereof. Depending on the material of the adhesive sheath layer, the presence of a central region of the adhesive sheath layer between the proximal sheath layer and the absorbent core can enhance the flow of wound fluid to the absorbent core or slow down the absorption of wound fluid. An adhesive sheath layer having substantially the same shape and size as the proximal and / or distal sheath layers, i.e., having no opening in the middle thereof, can also simplify the manufacturing process of the dressing. Moreover, such a continuous adhesive sheath layer between the absorbent core and the proximal sheath layer can reduce the pressure exerted on the wound by the expanded absorbent core.

[0017] It should be understood that the adhesive sheath layer is preferably liquid permeable, particularly in the embodiment in which it is located between the absorbent core and the proximal sheath layer. Because the adhesive sheath layer is liquid permeable, wound exudate can pass through the layer and reach the layer of more distal positioning, such as the absorbent core. To the permeability of liquid, particularly wound exudate, can be achieved by different strategies. For example, the adhesive sheath layer can have apertures, perforations or incisions. The apertures, perforations or incisions allow liquid to pass through the layer. Alternatively, the adhesive sheath layer can be a fiber mesh or a nonwoven fabric. The open structure of the fiber mesh and / or the nonwoven fabric enables fluid to pass through the layer. In one embodiment, the adhesive sheath layer is a fiber mesh, i.e. a layer with a fiber mesh structure. The term "fiber mesh" used herein refers to a net or a mesh made of or comprising fibers. The fiber can be a staple fiber, such as a fiber with an average length of 10 mm or less, 5 mm or less, 3 mm or less or 1 mm or less.

[0018] The adhesive sheath layer may be between the proximal sheath layer and the absorbent core or between the distal sheath layer and the absorbent core, wherein the former alternative is preferred. The presence of an adhesive sheath layer between the proximal sheath layer and the absorbent core may increase the mechanical resistance on the proximal side of the absorbent core. Thus, it is found that the absorbent core extends to a greater extent from the wound site. Thus, the pressure applied by the expanded absorbent core is reduced.

[0019] The adhesive sheath layer comprises or consists of an adhesive which is suitable for connecting sheath layers arranged on opposite sides of the adhesive sheath layer. This means that the adhesive sheath layer either comprises an adhesive layer on its proximal end as well as on its distal side, or that it is entirely an adhesive layer (e.g., impregnated with an adhesive or consisting of an adhesive). The adhesive sheath layer may also be designated as a "fusible layer". As mentioned above, the preferred adhesive sheath layer consists of an adhesive. For example, it may be an adhesive mesh. The adhesive sheath layer may, for example, consist of or include a copolyamide or a copolyester, wherein copolyamide is preferred.

[0020] The adhesive sheath layer may include or consist of an adhesive that is solid at room temperature but viscous when melted (hot melt adhesive), such as a copolyamide or copolyester adhesive. These adhesives are generally solid at room temperature to body temperature, i.e. at least in the range of 20°C to 40°C. At higher temperatures, typically temperatures above 100°C, the adhesive melts. It hardens after cooling. The hot melt adhesive used in the adhesive sheath layer of the present invention may have a melting temperature of 100°C or higher, such as 120°C or higher. However, it is preferred that the melting temperature of the hot melt adhesive is lower than 200°C to avoid damaging other dressing components. Therefore, the hot melt adhesive preferably has a melting temperature of 200°C or lower, preferably 180°C or lower, or most preferably 160°C or lower. In other words, the melting temperature of the hot melt adhesive may be 100° to 200°C, 100° to 160°C, 110° to 150°C, such as about 130°C. Suitable hot melt adhesives are known in the art. The adhesive sheath layer may be, for example, a fiber web consisting of or comprising a copolyamide or copolyester hot melt adhesive having a melting temperature of 100° C. to 160° C.

[0021] The adhesive jacket layer may be relatively light weight. For example, the weight of the adhesive jacket layer may be 4 to 20 g / m 3 , preferably 6 to 15 g / m 3 , for example 8 to 12 g / m 3 .

[0022] In a second related aspect, the invention accordingly relates to a method of producing a wound dressing according to any preceding claim, comprising the step of heat sealing the sheath through the cover layer. The method advantageously allows the wound dressing to be manufactured in a short time and facilitates straightforward and economical manufacture. All layers of the wound dressing may be stacked on top of each other and the sheath may then be sealed through the cover layer, i.e. heat may be applied to all layers including the cover layer and the adhesive layer.

[0023] The seal between the adhesive sheath layer, the proximal sheath layer and the distal sheath layer in the wound dressing according to the present invention preferably forms a sealed edge in the sheath. The sealed edge may extend around the entire periphery of the sheath in a plane substantially parallel to the adhesive layer. The width of the sealed edge may be 0.5 cm to 3 cm, 0.8 cm to 2.5 cm, preferably 1 cm to 1.8 cm. In other words, the width of the sealed edge may be 0.5 cm or more, 0.75 cm or more, 1 cm or more. The width of the sealed edge may be the same around the entire periphery of the sheath.

[0024] The length and width of the sheath layer and the adhesive sheath layer can be, for example, 2 cm to 40 cm, 3 cm to 30 cm, preferably 4 to 25 cm, more preferably 6 cm to 10 cm. For example, the sheath layer and the adhesive sheath layer can have a substantially square shape with a width and length of about 9 to 11 cm.

[0025] At the proximal or distal end of the adhesive sheath layer (c), the absorbent core is disposed within the sheath. The absorbent core has a distal and proximal surface. The distal surface of the absorbent core is adjacent to the distal sheath layer or the adhesive sheath layer. The proximal surface of the absorbent core is adjacent to the proximal sheath layer or the adhesive sheath layer. Typically, the absorbent core is not attached to the sheath layer or the adhesive sheath layer, so that it is relatively free to move within the sheath and is not limited by its expansion during the absorption of wound fluid.

[0026] The absorbent core comprises one or more absorbent materials or is composed of one or more absorbent materials.Therefore, the core can absorb and retain fluid, such as wound fluid (exudate).The term "wound fluid" or "exudate" refers to the fluid that escapes from the wound, particularly due to the inflammatory process of plasma.Wound fluid or exudate are used to provide a wide range of components for the wound bed and the healing process that occurs there, including nutrients, growth factors and cytokines for fibroblasts and epithelial cells.Wound fluid also contributes to the cleaning of the wound and the degradation of damaged tissue.

[0027] Absorbent core is a flat layer, which generally includes textile or nonwoven fabric, to support the absorbent material included in the core with structurally and / or functionally stable absorbent material. Nonwoven material is a fabric-like material made by combining short fibers and / or long fibers by chemical, mechanical, heating or solvent treatment. Nonwoven fabric can be manufactured, for example, by grinding fibers. Exemplary nonwoven fabric includes airlaid fabric, which is a nonwoven material made of cellulose and polyolefin fibers.

[0028] The absorbent material may be embedded in a flat layer, such as in a woven or nonwoven material. The absorbent material may be, for example, a superabsorbent material, such as one or more superabsorbent materials selected from the group consisting of superabsorbent fibers and superabsorbent particles. In one embodiment, the absorbent core is an airlaid pad comprising a cellulosic nonwoven with embedded superabsorbent particles.

[0029] Due to improved structural integrity and reduced risk of delamination, the absorbent core can be relatively thick. For example, when the core is dry, its thickness can be 1mm or larger, preferably 2mm or larger. In other words, the thickness of the absorbent core can be from 1mm to 10mm, for example from 2mm to 5mm. During the fluid absorption process, the thickness of the absorbent core can significantly increase, for example up to 5cm or more. In other words, during the fluid absorption process, the thickness of the absorbent core can increase 10 times or more.

[0030] The absorbent core may have a rectangular (e.g. square) shape, such as a rectangular shape with rounded edges; an oval shape; a circular shape or an irregular shape. The term "shape" as referred to herein refers to the shape that can be seen when observing the absorbent core or other parts of the wound dressing described herein from a proximal or distal direction, i.e. the shape in the XY plane, wherein the XY plane is substantially parallel to the skin or surface of the body part on which the wound dressing can be worn, i.e. substantially parallel to the adhesive layer.

[0031] Typically, the shape of the absorbent core will be substantially the same as the shape of the sheath and wound dressing. For example, a rectangular wound dressing may include a rectangular sheath and a rectangular absorbent core; an oval wound dressing may include an oval sheath and an oval absorbent core. It will be appreciated that the core will be smaller than the sheath in the XY plane, i.e., smaller than the sheath layer and the adhesive sheath layer.

[0032] The absorbent core may have a length and width of, for example, 1 cm to 35 cm, preferably 2 cm to 30 cm, more preferably 3 to 20 cm. For example, the absorbent core may have a square shape with a width and length of 3 to 5 cm, such as 4 cm. In a specific embodiment, the absorbent core may have a square shape with a width and length of 2 to 6 cm, and the sheath layer and the adhesive sheath layer may have a square shape with a width and length of 6 to 10 cm.

[0033] As noted above, in addition to the adhesive sheath layer, the sheath includes (b2) a proximal sheath layer on the proximal side of the absorbent core and adhesive sheath layer and (b3) a distal sheath layer on the distal side of the absorbent core and adhesive sheath layer.

[0034] The sheath layer, in particular the proximal sheath layer, is a liquid permeable layer. The material of the sheath layer will support the absorption of fluid by the absorbent core, for example by slowing down the absorption of fluid, increasing the absorption rate or even increasing further absorption capacity. Preferably, the sheath layer increases the rate of fluid absorption from the wound to the absorbent core, for example by utilizing capillary forces in the sheath layer, etc.

[0035] Due to the openings in the underlying adhesive layer, at least a portion of the proximal sheath layer may be in direct contact with the wound and / or skin of the wearer. This means that at least the middle region of the proximal sheath layer may be adapted to be in direct contact with the body part on which the wound dressing is worn. Thus, the proximal and (optionally) distal sheath layers will have good biocompatibility and be of a material that can be easily removed from wet wound tissue.

[0036] It is known that certain absorbent materials can adhere to the wound bed. This adhesion is considered to be harmful because it usually causes pain and damage to the newly formed wound tissue during the dressing removal process, thereby delaying healing. Therefore, the material of the proximal and optionally also the distal sheath layer can be a low-adhesion material, preferably selected from the group of low-adhesion materials consisting of polymer films or fabrics (woven or non-woven), usually treated in such a way that they adhere less to the wound. Commercial products comprising a non-adhesive layer or a low-adhesion layer are, for example, Profor TM WCL (sold by Smith & Nephew), (Depend on Health Care). The term "low adhesion" material is used herein to describe a material that adheres less to the wound bed than the absorbent core.

[0037] The proximal sheath layer and / or the distal sheath layer may for example comprise a woven or nonwoven material or be composed of a woven or nonwoven material, wherein the latter is preferred. The nonwoven material may for example be composed of a material selected from a group or include a material selected from the group, the group being composed of polypropylene, polyester, copolyester and combinations thereof. The nonwoven material may be spunbonded. The material may have a filament laying structure.

[0038] To allow the absorbent core to expand within the sheath, the outer dimensions of the unwetted absorbent core are smaller than the inner dimensions of the sheath.

[0039] The sheath encloses an inner sheath space having an inner sheath area extending parallel to the adhesive layer within the flat and non-wetted absorbent dressing. The inner sheath space is the free volume within the sheath when the absorbent core and adhesive sheath layer are not present within the space and the wound dressing layer is not elastically or plastically deformed. Thus, the inner sheath space is limited on the proximal side by the proximal sheath layer, on the distal side by the distal sheath layer, and laterally by the sealed outer edge.

[0040] The inner jacket area is a cross-section of the inner jacket space at its maximum expansion. Typically, the inner jacket area is substantially the same as the area of ​​the portion of the jacket layer that does not participate in the sealing of the outer edge. The size of the inner jacket area can be 2 cm 2 Up to 1500cm 2 , 4cm 2 Up to 840cm2 、9cm 2 Up to 570cm 2 , or 15cm 2 Up to 80cm 2 , for example 25cm 2 .

[0041] The absorbent core has an outer region extending parallel to the adhesive layer within the flat and non-wetted absorbent dressing. The outer region is the surface area of ​​the absorbent core that is maximally expanded in a plane substantially parallel to the absorbent layer. This outer region of the absorbent core may have a 1 cm 2 Up to 1225cm 2 , preferably 4cm 2 Up to 900cm 2 , more preferably 9cm 2 Up to 36cm 2 Size, for example 16cm 2 In an exemplary embodiment, therefore, the outer area of ​​the absorbent core may be 1 cm 2 Up to 1225cm 2 , and the inner sheath area can be 2cm 2 Up to 1500cm 2 .

[0042] As can be seen, the size of the outer region of the absorbent core is smaller than the size of the inner sheath region. The outer region of the absorbent core can be, for example, 40% to 90% (wherein the size of the inner sheath region is 100%), 45% to 85%, 50% to 80%, 55% to 75%, 60% to 70%, for example about 65% of the size of the inner sheath region. In other words, the size of the outer region of the absorbent core is preferably 90% or less, 85% or less, 80% or less, 75% or less, 70% or less, 65% or less of the size of the inner sheath region, wherein 75% or less is particularly preferred. If not otherwise specified, all values ​​mentioned herein refer to the wound dressing in an unmoistened state.

[0043] The wound dressing according to the present invention further comprises (a) a covering layer. The covering layer is located on the distal side of the sheath, so that when the wound dressing is worn, the covering layer is farthest from the wound and the skin surface. As will be explained in more detail below, in some embodiments, the covering layer is not in direct contact with the surface of the wearer's skin because the adhesive layer has substantially the same size and shape as the covering layer and is located between the covering layer and the surface of the skin or other body part to be treated over the entire area of ​​the covering layer. Therefore, there is no need to apply an adhesive to the covering layer to adhere to the skin or other body part to be treated. The covering layer can be completely free of adhesive. The bonding between the covering layer and the other layers of the dressing is ensured by the adhesive contained in the adhesive layer (further described elsewhere herein).

[0044] The cover layer can be highly flexible to allow the volume of the absorbent core to increase, thereby allowing the volume of the sheath to increase. The cover layer can be stretched and comprises a stretchable material for this purpose. The material can be elastic and / or plastically stretchable. The cover layer can have a tensile strength of 15 to 30N / 25mm. It can have an elongation of 400% or more, preferably 500% or more.

[0045] The cover layer can be liquid-impermeable, in particular water-impermeable. At the same time, it can be vapor-permeable. This ensures that wound fluid does not leak to the outside of the dressing, but the dressing has good breathability.

[0046] Suitable materials with the above properties are known in the art. The cover layer may, for example, consist of or include a material selected from the group consisting of polyurethane and copolyester, wherein polyurethane is preferred. The polyurethane may be a thermoplastic polyurethane or a non-thermoplastic polyurethane.

[0047] The thickness of the cover layer ensures the required flexibility of the cover layer as well as the required stability. This layer can have a thickness of 15 to 35 g / m 2 The weight of the product is preferably 20 to 30 g / m 2 weight.

[0048] The wound dressing according to the present invention further comprises (d) an adhesive layer on the wound-facing side of the sheath. Although the wound dressing may comprise more layers than those described above (cover layer; absorbent core; sheath consisting of a distal sheath layer, an adhesive sheath layer and a proximal sheath layer; and an adhesive layer), in a specific embodiment, the dressing consists of these layers.

[0049] The adhesive layer of the wound dressing comprises an opening through which fluid can enter the absorbent core from the wound. Typically, the opening will be substantially in the center of the adhesive layer, resulting in a frame shape or frame-like shape of the adhesive layer. The adhesive layer may be liquid impermeable.

[0050] The opening and the absorbent core may have substantially the same shape, such as a rectangular, circular, oval or an irregular shape of the same. Preferred shapes include rectangular shapes with rounded edges. Within the wound dressing, the absorbent core is aligned with the opening. In this context, the term "aligned" means that the absorbent core is disposed at the distal end of the opening, and the axis orthogonal to the absorbent core and the adhesive layer is the shared central axis of the opening and the absorbent core. The "central axis" is the axis passing through the respective entity in the middle thereof.

[0051] The area of ​​the opening, i.e. its size, can be 50% or more of the area of ​​the absorbent core, for example 60% or more, 70% or more, 80% or more, 90% or more, 100% or more, 110% or more. In other words, the area of ​​the opening can be 50% to 150%, 60% to 140%, 70% to 130% or 80% to 120% of the area of ​​the absorbent core. Therefore, the size of the opening and the size of the absorbent core in a plane parallel to the adhesive layer can be substantially the same.

[0052] Importantly, the size of the opening in the adhesive layer is typically smaller than the size of the sheath in a plane parallel to the adhesive layer. In other words, the size of the opening in the adhesive layer will be smaller than the size of the proximal sheath layer. Thus, ensuring that the sheath is securely held within the wound dressing.

[0053] In the wound dressing, the sheath is preferably aligned with the opening. In this context, the term "aligned" means that the sheath is disposed distal to the opening and an axis orthogonal to the sheath, in particular the absorbent core and adhesive layer within the sheath, is a shared central axis of the opening and the sheath.

[0054] The outer edge of the sheath - which may be wider, the same, or narrower than the outer edge of the sheath sealed as described above - may be covered by the adhesive layer, preferably surrounding the entire opening in the adhesive layer.

[0055] The adhesive layer has (i) a proximal side adapted to adhere to the body part facing the wound, and (ii) a distal side adhered to the outer periphery of the cover layer.

[0056] The adhesive layer may comprise a first adhesive on its proximal side. The first adhesive is adapted to adhere to the surface of a body part, preferably the skin, of the wearer. It also ensures that the dressing can be removed from the skin substantially without damaging the surface of the body part. It has been found that a particularly suitable first adhesive is an adhesive comprising silicone.

[0057] To ensure that the dressing adheres securely to the wearer's skin - also during expansion of the absorbent core - the first adhesive preferably has a high adhesion value to steel, for example from 0.5 to 0.8 N / cm, preferably from 0.6 to 0.7 N / cm.

[0058] The adhesive layer may include a second adhesive on its distal side. The second adhesive is suitable for adhering to the cover layer in the outer peripheral portion of the cover layer. The second adhesive, for example an acrylic adhesive. Alternative adhesives are known in the art.

[0059] In order to be able to adhere to the adhesive layer, the cover layer is larger than the sheath and protrudes on all sides of the sheath. The outer periphery is preferably shaped like a frame with a sheath in the middle. The outer periphery of the cover layer can have a width of, for example, 0.5 cm to 4 cm, 0.75 cm to 3 cm, 0.9 cm to 2 cm. In other words, the outer periphery can be 0.5 cm or larger, preferably 0.75 cm or larger, more preferably 1 cm or larger. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Exemplary embodiments of the invention are schematically illustrated in the drawings.

[0061] Figure 1 Schematically showing a wound dressing according to the present invention, wherein the adhesive sheath layer is on the proximal side of the absorbent core;

[0062] Figure 2 Shows Figure 1 An exploded view of a wound dressing;

[0063] Figure 3 Schematically shows Figure 1 A top view of a wound dressing;

[0064] Figure 4 schematically shows an alternative wound dressing according to the present invention, wherein the adhesive sheath layer is on the distal side of the absorbent core; and

[0065] Figure 5 A further alternative wound dressing according to the invention is schematically shown, wherein the size of the openings in the adhesive layer is smaller than the size of the absorbent core.

[0066] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. DETAILED DESCRIPTION

[0067] Other advantages, features and characteristics of the present invention will become apparent from the following detailed description of exemplary embodiments with reference to the accompanying drawings. However, the present invention is not limited to these exemplary embodiments.

[0068] Figure 1 and Figure 2 A side view and an exploded side view of a wound dressing 10 according to the present invention are schematically shown, wherein an adhesive sheath layer 18 is located on the proximal side of an absorbent core 16. The wound dressing 10 comprises a flexible, elastic PU cover layer 12, a sheath 14 and an adhesive layer 23.

[0069] The sheath 14 is composed of a proximal sheath layer 20, an adhesive sheath layer 18, an absorbent core 16 and a distal sheath layer 22 from the proximal end to the distal end. The proximal sheath layer 20 and the distal sheath layer 22 are composed of spunbonded nonwoven polypropylene. The adhesive sheath layer 18 is composed of a fiber web formed of copolyamide. The absorbent core 16 is airlaid, which has superabsorbent particles and cellulose fibers and has a thickness of about 1.25 mm.

[0070] The proximal jacket layer 20, the adhesive jacket layer 18, the absorbent core 16 and the distal jacket layer 22 are aligned with each other, i.e., they share a common central axis. The proximal jacket layer 20, the adhesive jacket layer 18 and the distal jacket layer 22 are substantially the same in size. The outer region 46 of the absorbent core 16 is approximately 64% of the size of the inner jacket region 44. The jacket 14 provides an inner jacket space 42 that has a larger volume than the unwetted absorbent core 16.

[0071] The proximal jacket layer 20, the distal jacket layer 22 and the adhesive jacket layer have been fused together along their outer edges 32, 34, 36 (see FIG. Figure 2 ). For this purpose, the adhesive jacket layer 18 comprises a hot melt adhesive. In order to fuse the layers, all layers (cover layer 12, distal jacket layer 22, absorbent core 16, adhesive jacket layer 18, proximal jacket layer 24 and adhesive layer 23) have been superimposed on each other in the correct order. Subsequently, heat in the range of 120° C. to 160° C. is applied to the outer edges 32, 34, 36 through the cover layer 12, resulting in a sealed edge 40.

[0072] The sheath 14 is surrounded by a second sheath established by the interconnected cover layer 12 and adhesive layer 23. The adhesive layer 23 comprises an opening 26 in the middle thereof, which is aligned with the absorbent core 16. The opening 26 is slightly larger in its maximum extension in a plane parallel to the adhesive layer 23 than the absorbent core 16. The sheath 14 is slightly larger than the opening 26, ensuring that the absorbent core 16 is securely fixed within the wound dressing 10.

[0073] The frame-shaped adhesive layer 23 has an acrylic adhesive on its distal side 25 so that it adheres to the outer area of ​​the proximal sheath layer 20 and the outer periphery 30 of the cover layer. In addition, the adhesive layer 23 has a silicone adhesive on its proximal side 24 so that it is suitable for adhering to a body part (not shown).

[0074] Figure 3 Schematically shows Figure 11 , which shows the cover layer 12 in the top view. Since the cover layer 12 is transparent, the layers underneath it can also be seen. The outer peripheral edge 30 of the cover layer 12 extends around the entire periphery of the cover layer 12. Next to it, the sealed outer edge 32 of the sheath 14 can be seen. Next to this heat-sealed part of the sheath 14 and between the absorbent core 16 and the sealed outer edge 32, the free inner sheath space 42 can be seen.

[0075] Figure 4 An alternative wound dressing 10 according to the present invention is schematically shown, wherein an adhesive sheath layer 18 is located on the distal side of the absorbent core 16. Apart from this difference, the wound dressing 10 is substantially the same as Figures 1 to 3 Same as shown in .

[0076] Figure 5 A further alternative wound dressing 10 according to the present invention is schematically shown, wherein the size of the opening 26 in the adhesive layer is smaller than the size of the absorbent core 16. Apart from this difference, the wound dressing 10 is substantially the same as Figure 4 Same as shown in .

[0077] Reference numerals list

[0078] 10 Wound Dressing

[0079] 12 Covering

[0080] 14 Sheath

[0081] 16 Absorbent core

[0082] 18 Adhesive sheath layer

[0083] 20 Proximal sheath layer

[0084] 22 Distal sheath layer

[0085] 23 Adhesion layer

[0086] 24 Proximal side

[0087] 25 Distal side

[0088] 26 Opening

[0089] 28 Body Parts

[0090] 30 Outer periphery

[0091] 32 Outer edge

[0092] 34 Outer edge

[0093] 36 Outer edge

[0094] 40 Sealing edge

[0095] 42 Inner sheath space

[0096] 44 Inner sheath area

[0097] 46 External area.

Claims

1. A wound dressing (10) comprising or consisting of the following composition: (a) a covering layer (12); (b) a sheath (14) on the wound-facing side of the cover layer (12), (c) an absorbent core (16) within the sheath (14), and (d) an adhesive layer (23) on the wound-facing side of the sheath (14); Wherein, the sheath (14) comprises: (b1) an adhesive sheath layer (18), (b2) a proximal sheath layer (20) on the proximal side of the absorbent core (16) and the adhesive sheath layer (18); and (b3) a distal sheath layer (22) on the distal side of the absorbent core (16) and the adhesive sheath layer (18); The adhesive layer (23) includes an opening (26), and the adhesive layer (23) has: (i) a wound-facing proximal side (24) adapted to be adhered to a body part (28), and (ii) adhered to the distal side (25) of the outer peripheral edge (30) of the cover layer (12); And wherein the adhesive sheath layer (18) comprises or consists of an adhesive, and the outer edges (32, 34, 36) of the adhesive sheath layer (18), the proximal sheath layer (20) and the distal sheath layer (22) are connected by sealing to form the sheath (14), and the absorbent core (16) is not connected to the proximal sheath layer (20) and the distal sheath layer (22) or the adhesive sheath layer (18).

2. The wound dressing (10) according to claim 1, in, The adhesive is a hot melt adhesive.

3. The wound dressing (10) according to claim 1 or 2, in, The adhesive sheath layer (18) is a fibrous mesh layer.

4. The wound dressing (10) according to claim 1, in, The seal forms a sealed edge (40) having a width of 0.5 cm to 3 cm.

5. The wound dressing (10) according to claim 1 or 2, in, The adhesive sheath layer (18) is between the proximal sheath layer (20) and the absorbent core (16).

6. The wound dressing (10) according to claim 1 or 2, in, The adhesive layer (23) comprises a first adhesive on its proximal side (24).

7. The wound dressing (10) according to claim 1 or 2, in, The adhesive layer (23) comprises a second adhesive on its distal side (25).

8. The wound dressing (10) according to claim 1 or 2, in, The absorbent core (16) is aligned with the opening (26).

9. The wound dressing (10) according to claim 1 or 2, in, The area of ​​the opening (26) is 80% to 120% of the area of ​​the absorbent core (16).

10. The wound dressing (10) according to claim 1 or 2, in, The proximal sheath layer (20) and / or the distal sheath layer (22) comprises or consists of a non-woven fabric material.

11. The wound dressing (10) according to claim 1, in, The sheath (14) encloses an inner sheath space (42), the inner sheath space (42) having an inner sheath region (44), the inner sheath region (44) extending parallel to the adhesive layer (23) within the flat and non-wetted absorbent dressing (10); the absorbent core (16) having an outer region (46), the outer region (46) extending parallel to the adhesive layer (23) within the flat and non-wetted absorbent dressing (10); and the size of the outer region (46) of the absorbent core (16) is 40% to 90% of the size of the inner sheath region (44).

12. The wound dressing (10) according to claim 11, in, The outer region (46) of the absorbent core (16) is 50% to 80% of the size of the inner sheath region (44).

13. The wound dressing (10) according to claim 11 or 12, in, The outer region (46) of the absorbent core (16) is 1500 mm 2 Up to 60000mm 2 , and the inner jacket area (44) is 2400mm 2 Up to 70000mm 2 .

14. The wound dressing (10) according to claim 1 or 2, in, The cover layer (12) is composed of or includes a material selected from the group consisting of polyurethane and copolyester.

15. The wound dressing (10) according to claim 1 or 2, in, The cover layer (12) is liquid-impermeable.

16. The wound dressing (10) according to claim 1 or 2, in, The cover layer (12) has a thickness of 15 to 35 g / m 2 weight.

17. The wound dressing (10) according to claim 1 or 2, in, The cover layer (12) has a tensile strength of 15 to 30 N / 25 mm.

18. The wound dressing (10) according to claim 1 or 2, in, The cover layer (12) has an elongation of 400% or more.

19. The wound dressing (10) according to claim 2, in, The hot melt adhesive has a melting temperature of 100° to 160°C.

20. The wound dressing (10) according to claim 1 or 4, in, The seal is a heat seal.

21. The wound dressing (10) according to claim 4, in, The sealed edge (40) has a width of 1 cm to 1.8 cm.

22. The wound dressing (10) according to claim 6, in, The first adhesive includes silicone.

23. The wound dressing (10) according to claim 7, in, The second adhesive is an acrylic adhesive.

24. The wound dressing (10) according to claim 16, in, The cover layer (12) has a thickness of 20 to 30 g / m 2 weight.

25. The wound dressing (10) according to claim 18, in, The cover layer (12) has an elongation of 500% or more.

26. A method for producing a wound dressing (10) according to any one of the preceding claims, comprising the step of heat sealing the sheath (14) through the cover layer (12).

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