Method for producing drainage films, tubular drainage film and wound care kit

Abstract

This is a method for producing double-walled drainage film with an open drainage gap, characterized by the fact that the method involves the following steps: i) providing the first strip-shaped element and the second strip-shaped element; ii) Puncture of the first and second strip-shaped elements, whereby at least one, preferably more than one, opening is created in each of the first and second strip-shaped elements to allow the passage of body fluids; iii) the first strip-shaped element must be placed on top of the second strip-shaped element in such a way that the first and second strip-shaped elements are approximately parallel; iv) To obtain a double-walled drainage film with an open drainage gap between the first and second strip-shaped elements, the first and second strip-shaped elements must be joined at least at one connection point, preferably using ultrasonic welding.

Description

[0001] The invention relates to a method for producing a double-walled drainage film with an open drainage space and a method for producing a tubular drainage film. The invention further relates to a tubular drainage film, a wound care kit, and the tubular drainage film or wound care kit for use in wound care.

[0002] Drainage films are required for various medical conditions and traumas, particularly during or after surgery in the abdominal, thoracic, or pelvic cavities. For example, they are needed when temporary coverage of an open wound and / or drainage of bodily fluids from the wound area is necessary. Covering open wounds may be required, for instance, when multiple procedures are performed daily, both to allow rapid access to internal organs and to reduce the adverse effects of exudate buildup in the wound area. Temporary coverage can significantly reduce mortality in some cases. Furthermore, suctioning, especially postoperative drainage, of bodily fluids may be necessary to promote wound healing, as fluid accumulation such as blood or wound exudate can disrupt the healing process.

[0003] From a medical perspective, drainage films suitable for the aforementioned applications must meet two main requirements. Firstly, they must ensure effective exudate management in the wound area, particularly when used in the open abdominal, thoracic, or pelvic cavities, meaning the removal of bodily fluids from the entire wound area. Secondly, they should minimize friction between the wound or surrounding organs and the drainage film, while simultaneously providing sufficient protection for the wound from the environment. Finally, they must be designed to prevent contaminants from entering the open wound or the patient's body through the drainage film.

[0004] EP 0 261 167 B1 describes a fluid-permeable wound dressing intended for direct contact with the wound bed, which has a hydrophobic layer to prevent the dressing from adhering to the wound and thus potentially contaminating the wound. However, the wound dressing described in this document does not provide satisfactory exudate management in the wound area.

[0005] To improve exudate management in the wound area, US 7,381,859 B2 proposes a wound dressing in which a foam-like layer is sandwiched between two fluid-permeable, film-like, sheet-like elements, which may be made of plastic film. This foam layer is designed to absorb exudates. However, the wound dressing described in this document has proven problematic because satisfactory exudate removal cannot be achieved at the edges of the dressing, leading to complications in wound care at these edges.

[0006] In WO 2007 / 118652 A1, a wound contact layer is described onto which absorbent secondary dressings can be applied without adhesive. This layer is designed to form a first smooth surface and a second surface with a rough texture and numerous three-dimensional perforations. When using this known wound dressing, the downstream absorbent layers are replaceable to ensure satisfactory wound care over a longer period. However, even with the wound dressing systems described in the aforementioned document, it has proven problematic that satisfactory exudate management across the entire wound area, particularly in the case of deep internal wounds, is not achievable.

[0007] EP 2 424 477 B1 describes a double-walled film for wound dressing that has an open drainage space. However, with the wound dressing known from this document, it has proven problematic that satisfactory coverage of complex wound areas, particularly deep wounds, cannot be achieved. Furthermore, the manufacturing of the known wound dressing has proven problematic with regard to production efficiency.

[0008] US patent 2022 / 0152287 A1 discloses a wound care arrangement with a multi-layered drainage film and a fluid-tight fixation film.

[0009] In light of the problems described above in the prior art, the invention aims to provide a drainage film that enables effective exudate management across the entire wound area without contaminating the wound, particularly in the case of complex wounds, such as surgical wounds of the internal organs and / or the musculoskeletal system. Furthermore, the invention aims to provide improved methods for manufacturing drainage films. Method for manufacturing a double-walled drainage membrane

[0010] According to the invention, this problem is solved by the further development of known methods specified in claim 1 and a tubular drainage film according to claim 15.

[0011] In the inventive method, connecting the first and second sheet-shaped elements and perforating them creates an open drainage space. This space allows capillary action between the individual sheet-shaped elements, preventing the outflow of body fluids, especially exudates, from the drainage space and enabling the distribution of body fluids across the entire drainage surface without the need for additional measures such as providing additional absorbent materials. This ensures effective exudate management across the entire wound area because there are no peripheral areas lacking capillary function that could negatively impact exudate management. The inventive method allows for the production of drainage films that can be easily adapted to any size.Any wound structure, even for endoluminal application, can be custom-cut, and the desired drainage function can be ensured across the entire wound surface. The process can include manufacturing the drainage film with a smooth surface to prevent tissue and wound bed tissue, as well as surrounding organs, from adhering to it. Furthermore, the process can include facilitating the entry of body fluids into the drainage space of the drainage film by making the sheet-like elements themselves from a fluid-permeable material.

[0012] The stability of the drainage films produced by the inventive method can be improved if the at least one opening enabling the passage of body fluids is formed by a channel extending from the first or second sheet-shaped element towards the other sheet-shaped element and opening into the drainage space, the wall of which is formed integrally with the respective sheet-shaped element by perforation of the sheet-shaped element.

[0013] In the embodiment of the invention described last, exudate management can be improved particularly effectively if the opening or channel is designed such that its cross-sectional area decreases in a plane extending perpendicular to a depth direction of the drainage film, from one linear element towards the other, particularly to maintain a capillary effect that promotes the entry of body fluids into the drainage space. This approach supports the removal of exudate from the wound area and prevents backflow from the drainage space into the wound area.

[0014] Within the scope of the invention, it has proven particularly advantageous for effective exudate management if the at least one opening allowing the passage of body fluids has a diameter in the range of 100 µm to 2000 µm, preferably in the range of 300 µm to 700 µm, and more preferably in the range of 400 µm to 600 µm. It has been found that excellent capillary action can be achieved by at least one, and preferably a plurality, of openings allowing the passage of body fluids with such a diameter.

[0015] Furthermore, it has been found that particularly good exudate management and stability of the drainage membrane are ensured when the first and second sheet-like elements are connected at a multitude of fastening points, preferably at a multitude of fastening points arranged in a grid pattern. For excellent drainage capacity, the distance between adjacent fastening points is preferably 2 mm or more, more preferably 3 mm or more, and more preferably 5 mm or more. The multitude of fastening points can, for example, be arranged in a rectangular grid. A rectangular grid arrangement allows for particularly efficient production of the drainage membrane.

[0016] The joining of the sheet-like elements, while simultaneously ensuring the drainage space that provides the drainage effect, can be achieved via a multitude of point-like fastening areas, preferably arranged in a grid pattern. This joining can be accomplished by welding, gluing, or other permanent connection methods. The joining should, however, not impede but rather facilitate the removal of exudates. It has been found that joining by ultrasonic welding not only enables more efficient production of the drainage film than other methods for joining the sheet-like elements, but also produces particularly stable drainage films whose structural integrity is guaranteed even under mechanical stress, for example, in an endoluminal application.In particular, it has been shown that joining by means of ultrasonic welding enables the production of particularly durable drainage films and achieves a particularly advantageous bond strength of 0.5 N / 25.4 mm or more.

[0017] It has proven advantageous if the individual fastening areas in a section plane extending perpendicular to the depth direction have an area of ​​5 mm² or less, in particular 3 mm² or less, especially preferably 2 mm² or less, wherein the distance between individual fastening areas or individual grid points of the fastening areas arranged in a grid is 2 mm or more, in particular 3 mm or more, especially preferably 5 mm or more.

[0018] Regardless of whether the fastening is achieved by welding, gluing, or other joining methods, a material bridge connecting the inner boundary surfaces of the sheet-like elements can be formed in the fastening areas. It has been found that such a material bridge, which enhances the stability of the overall structure of the drainage membrane, can be produced with particular precision using ultrasonic welding. To maintain the desired capillary action in the drainage space, the distance between the inner boundary surfaces of the sheet-like elements is 5 mm or less, preferably 4 mm or less, and particularly preferably 2 mm or less. The distribution of exudates across the entire surface of the drainage membrane, utilizing capillary action in the drainage space, can be ensured if the distance between the inner boundary surfaces of the sheet-like elements is 0.05 mm or more, especially if the distance between the inner boundary surfaces of the sheet-like elements is 2 mm or less.The gap is 0.1 mm or more, particularly preferably 0.3 mm or more. For the production of high-quality drainage membranes, it has proven particularly advantageous to join the first and second sheet-like elements by ultrasonic welding, as this allows the desired gap between the first and second sheet-like elements, in particular between an inner boundary surface of the drainage space formed by the first sheet-like element and an inner boundary surface of the drainage space formed by the second sheet-like element, to be produced precisely and with quality assurance.It has been found that manufacturing the drainage film using ultrasonic welding allows for higher quality drainage films than if the distance between the inner boundary surfaces is ensured only by the depth of openings, especially funnel-shaped ones, since perforation is typically only carried out with limited accuracy.

[0019] For the application of the drainage film in wound care, it has proven particularly advantageous if the drainage film has a basis weight in the range of 30 g / m² to 90 g / m², preferably 40 g / m² to 80 g / m², and more preferably 50 g / m² to 70 g / m². The first and / or the second web-shaped element may comprise a plastic film, the plastic film preferably comprising polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, polyhydroxybutyrate, polylactide, and / or cellulose. Such plastic films have the advantage of effectively preventing the penetration of pathogens, such as bacteria, and the adhesion and ingrowth of tissue. The plastic film may, in particular, comprise polyethylene, preferably low-density polyethylene (LDPE). It has been found that web-shaped elements or...Plastic films containing polyethylene, in particular low-density polyethylene (LDPE), are particularly advantageous for the production and application of drainage films according to the invention. The first web-shaped element and / or the second web-shaped element can comprise polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, polyhydroxybutyrate, polylactide, and / or cellulose, preferably polyethylene, more preferably low-density polyethylene (LDPE). The structure of the web-shaped elements can be produced by means of a non-woven manufacturing process. Synthetic as well as natural fibers (e.g., silk, cotton), as well as inorganic fibers (glass ceramics, etc.) or metal (silver fibers), can be used to produce the non-woven or woven materials. Furthermore, the invention provides for the web-shaped elements to be equipped on one or both sides with an antibacterial or bacteriostatic layer.The antibacterial or bacteriostatic effect can be achieved, for example, by PHMB, silver, chlorhexidine, etc. To prevent the drainage films produced by the inventive method from sticking together, at least one web-shaped element can have a hydrophilic or hydrophobic finish. Furthermore, the application of swellable materials is also conceivable.

[0020] Regarding the application of the drainage film produced by the inventive method in wound care, it has proven particularly advantageous if the drainage film has a tensile strength of 7 N / 25.4 mm or more, an elongation at break of 40% or more, a porosity of 75 m³ / m² / min or more, and / or a bond strength of 0.5 N / 25.4 mm or more. Effective exudate management while simultaneously ensuring the structural integrity of the drainage film can thus be guaranteed. The tensile strength is preferably measured according to DIN EN ISO 527. For example, the drainage film can have a tensile strength of 7 N / 25.4 mm or more, measured according to DIN EN ISO 527. The elongation at break is preferably measured according to DIN EN ISO 527. For example, the drainage film can have an elongation at break of 40% or more, measured according to DIN EN ISO 527. The bond strength is preferably measured in accordance with Edana NWSP 401.0.R0.The drainage membrane can, for example, have a bond strength of 0.5 N / 25.4 mm or more, measured in accordance with or based on Edana NWSP 401.0.R0. Porosity is a measure of the ratio of void volume to the total volume of the drainage membrane.

[0021] In drainage films produced according to the inventive method, the at least one opening allowing the passage of body fluids, particularly when viewed from a planar perspective of the first or second sheet-like element, can have a round, circular, and / or oval shape. Such a shape enables the effective passage of body fluids from the wound area into the open drainage space of the drainage film.

[0022] In the drainage films produced by the method according to the invention, the desired removal of the exudate can be achieved while ensuring satisfactory overall stability of the drainage film if at least one web-shaped element, preferably both web-shaped elements, has / have a plurality of preferably grid-like, in particular rectangular, openings, wherein the distance between adjacent openings or grid points of a web-shaped element is 15 mm or less, preferably 5 mm or less, in particular 3 mm or less.With regard to the desired overall stability of the drainage films produced by the inventive method, it has proven particularly advantageous if the openings of the openings arranged in one of the sheet-like elements are positioned in a projection along the depth direction between the openings of the openings arranged in the other sheet-like element. To prevent the overall structure of the drainage film from collapsing, especially when negative pressure is applied, it has proven particularly beneficial if at least one channel forming an opening in a sheet-like element, preferably a plurality of such channels, extends in the depth direction over 50% or more of the total depth of the drainage space.

[0023] To ensure the desired permeability of the sheet-like elements, it has proven advantageous to perform the perforation such that the opening surface of each perforation facing the drainage space, in a plane perpendicular to the depth direction, measures 0.1 mm² or more, in particular 0.5 mm² or more, and most preferably 1 mm² or more. The desired capillary action can be achieved while preventing backflow of fluid from the drainage space into the wound space if the perforation is performed such that the opening surface of the perforations in the resulting drainage sheet measures 5 mm² or less, in particular 4 mm² or less, and most preferably 3 mm² or less.

[0024] As explained above, the openings in the channels forming the linear elements are created by perforations in these elements. In this context, to maintain a smooth surface that effectively prevents tissue or cells from adhering to the wound bed or surrounding organs, it has proven advantageous for the channel wall to be at least partially curved in a section plane extending parallel to the depth of the wound and to transition smoothly into the boundary surface of the linear element.

[0025] The method according to the invention can include applying an adhesive, in particular an adhesive material and / or a hook-and-loop fastener, in particular one or more barbs, to the drainage film. Such adhesives, adhesive materials, or hook-and-loop fasteners enable the manufactured drainage film to be attached to other structures, for example, body parts, surgical devices, absorbent bodies, tubes, wires, stents, introducers, and / or devices for negative pressure therapy. For example, the method can include applying the adhesive, adhesive material, and / or hook-and-loop fastener to two opposite edges of the drainage film.Such a drainage film can then be used to wrap around a structure, for example selected from absorbent bodies, tubes, wires, stents, insertion aids, and devices for negative pressure therapy, and to fix the drainage film to the structure by connecting the adhesive, adhesive material or Velcro fastener of the two opposite edges.

[0026] From a manufacturing perspective, it has proven particularly advantageous if step ii) is carried out before or after step iii), and / or step iv) is carried out after step iii) and before or after step ii).

[0027] The method according to the invention can further comprise forming a three-dimensional, preferably tubular, structure from the drainage film. The advantage of such three-dimensional structures, for example tubular structures, is that they can be used for more complex wounds, for example deep wounds, or in deep regions of the body. In particular, such three-dimensional structures, such as tubular structures, can even be used endoluminally, for example in the gastrointestinal tract or in fistulas. The drainage film can be tubular, for example for endoluminal application and / or to accommodate a drainage tube.

[0028] In terms of manufacturing technology, it has proven particularly advantageous if such a three-dimensional structure is formed by welding, in particular ultrasonic welding or laser welding, by thermal joining, in particular by means of UV or hot air, using an adhesive agent and / or by deep drawing, in particular by deep drawing the first and second web-shaped elements joined in step iv). Method for producing a tubular drainage film

[0029] The object of the invention is further achieved by an inventive method for producing a tubular drainage film, characterized in that the method comprises the following steps: a) Providing a drainage film, preferably a double-walled drainage film with an open drainage space, more preferably a double-walled drainage film produced according to the inventive method for producing a double-walled drainage film; b) Folding over, in particular folding, the drainage film around a folding line, in particular folding line, such that the drainage film has an overlap area that can be joined to form a connecting line; wherein, preferably, the drainage film has a first edge and a second edge running substantially parallel to the first edge, and the drainage film is folded over itself along the folding line.a) The drainage film is folded so that it has an overlap area along the first and second edges that can be joined to the connecting line; c) The drainage film is joined along the overlap area, forming a connecting line; d) A tubular drainage film is obtained.

[0030] Furthermore, the object of the invention is achieved by an inventive method for producing a tubular drainage film, characterized in that the method comprises the following steps: a) Providing a drainage film, preferably a double-walled drainage film with an open drainage space, more preferably a double-walled drainage film produced according to the inventive method for producing a double-walled drainage film; b) Arranging a first edge of the drainage film on the elastic material such that an overlap area connectable to form a connecting line is created between the first edge of the drainage film and the elastic material; c) Connecting the drainage film and the elastic material along the overlap area between the first edge of the drainage film and the elastic material, thereby forming a connecting line; d) Folding over, in particular folding, the drainage film with respect toa folding line, in particular a fold line, onto the elastic material such that an overlap area, which can be joined to form a connecting line, is created between a second edge of the drainage film, preferably a second edge of the drainage film running substantially parallel to the first edge, and the elastic material; e) joining the drainage film and the elastic material along the overlap area between the second edge of the drainage film and the elastic material, thereby forming a connecting line; f) obtaining a tubular drainage film.

[0031] The object of the invention is also achieved by an inventive method for producing a tubular drainage film, characterized in that the method comprises the following steps: a) Providing a drainage film, preferably a double-walled drainage film with an open drainage space, more preferably a double-walled drainage film produced according to the inventive method for producing a double-walled drainage film; b) Winding the drainage film around a winding axis such that the drainage film has an overlap area formed by the winding around the winding axis, which can be joined to form a connecting line, in which the drainage film is present in at least two layers; c) Joining a first layer and a second layer of the drainage film, which is present in at least two layers in the overlap area, preferably by an adhesive or a connecting agent; wherein, preferably, a connecting line is formed; d) Obtaining a tubular drainage film.

[0032] It has been found that the aforementioned methods according to the invention for producing a tubular drainage film each efficiently provide a tubular drainage film that enables uniform drainage performance even in complex wound regions, for example, in wounds located deep within the body. The following descriptions refer to all three aforementioned methods according to the invention for producing a tubular drainage film. Each of the aforementioned methods for producing a tubular drainage film can have the following properties.

[0033] From a manufacturing perspective, it has proven particularly advantageous if the joining is carried out by welding, in particular ultrasonic welding or laser welding, by thermal joining, in particular by means of UV or hot air, by an adhesive, in particular an adhesive or a hook and loop fastener, and / or by a connecting element, in particular a clamp.In particular, joining the drainage film along the overlap area, joining the drainage film and the elastic material along the overlap area between the first edge of the drainage film and the elastic material, joining the drainage film and the elastic material along the overlap area between the second edge of the drainage film and the elastic material, as well as joining a first layer and a second layer of the drainage film, which is at least double-layered in the overlap area, can be carried out by welding, in particular ultrasonic welding or laser welding, by thermal joining, in particular by means of UV or hot air, by an adhesive, in particular an adhesive or a hook and loop fastener, and / or by a fastener, in particular a clamp.

[0034] A fastener can be, for example, a clamp, a cord, a thread, a seam (such as an elastic seam or a seam made of an elastic material), or an annular application aid. For instance, a drainage film can be wound around a winding axis, particularly around a drainage tube, and then secured as a tubular drainage film using a fastener, such as a clamp or annular application aid. An overlap area, such as the overlap between the first and second edges of a double-walled drainage film, can be joined using an elastic seam. An elastic seam increases the elasticity of the tubular drainage film.

[0035] The manufactured tubular drainage films have particularly advantageous properties for medical applications when the joining is carried out by ultrasonic welding, preferably at a speed in the range of 0.1 to 5.0 m / min, a power in the range of 50 to 500 watts and / or a pressure in the range of 5 N to 100 N. Such a joining method enables a stable connection line that ensures high tear resistance even under mechanical stress.

[0036] The joining process according to the invention for producing a tubular drainage film, in particular joining the drainage film along the overlap area, joining the drainage film and the elastic material along the overlap area between the first edge of the drainage film and the elastic material, joining the drainage film and the elastic material along the overlap area between the second edge of the drainage film and the elastic material, and / or joining a first layer and a second layer of the drainage film, which is present in at least two layers in the overlap area, can include arranging the drainage film in an ultrasonic welding device and welding the drainage film, in particular by means of a welding die, e.g. an L-shaped welding die, to form a tubular drainage film.It has been shown that tubular drainage films can be manufactured efficiently and to a high quality using appropriate welding molds.

[0037] Furthermore, it has been shown that the properties of the cut edge are particularly suitable for the functionality of the drainage membrane when the joining is carried out by ultrasonic welding using a cutting wheel with a cutting edge radius of 0.2 mm or less, and / or using a cutting wheel with a grinding angle of 15° or less towards the fold line, and / or with a grinding angle of 75° or less away from the fold line. This prevents material residues, which could impair the functionality of the drainage membrane, from remaining on the cut edge.

[0038] Joining by welding, particularly ultrasonic welding, can be achieved, for example, by heating and fusing the material in the overlap area—such as the double-walled drainage membrane and / or an elastic material—using the sonotrode vibrated by the generator. A cutting wheel can be used to create a weld, such as a cutting wheel capable of simultaneous welding and cutting. This type of cutting wheel removes excess material during the welding process. Alternatively, a conventional cutting wheel can be used to create a joint. Ultrasonic welding can be performed, for example, with a Nucleus Rotosonic DX1 - TC 12 flatbed ultrasonic welding device, operating at an ultrasonic frequency of approximately 35 kHz.

[0039] To ensure the smoothest possible seam, and in particular to prevent any functional impairment of the tubular drainage membrane that might occur due to a rough seam, an edge strip of the drainage membrane located on the side of the seam opposite the fold line can be removed during or after joining, especially by punching. Punching can also be used to remove any remaining material that is not needed.

[0040] It has been found that for the functionality of the tubular drainage film, it is particularly advantageous if the process is carried out in such a way that the connection line, for example, a weld seam, has a width of 2 mm or less, preferably 1 mm or less, and more preferably 0.5 mm or less, along one circumferential direction of the tubular drainage film. To prevent any impairment of the product's function, it is particularly advantageous to provide the narrowest possible connection line, especially the weld seam.Furthermore, it has proven particularly advantageous for ensuring functionality throughout the entire tubular structure if the connection line along a radial direction of the tubular drainage film, or in a depth direction extending perpendicular to the tube axis, has a thickness of 1 mm or less, preferably 750 µm or less, more preferably 450 µm or less. Depending on how the joining is carried out in the inventive methods for producing tubular drainage films, the material in the overlap area, particularly at the connection line, can fuse and thus form a material bridge, for example, if the joining is carried out by welding, especially ultrasonic welding.

[0041] According to the invention, the method for increasing the stability of the drainage film can include attaching a reinforcing element, in particular a reinforcing strip or a reinforcing film, in a region of the connection line, preferably by arranging the reinforcing element in the overlap area before joining, and / or at least at one end of the hose. A reinforcing strip can be provided, for example, by providing the drainage film in a double layer in the area to be reinforced or by attaching a reinforcing material, for example a polyethylene film, in the area to be reinforced. It has been found that a film, in particular a polyethylene film, has a particularly advantageous reinforcing effect as a reinforcing element.

[0042] For example, the reinforcing element can be additionally welded during the joining process by positioning it in the overlap area before joining, thus increasing the tensile strength of the drainage film, particularly at the joint. The reinforcing element not only increases the tensile strength of the drainage film but can also offer further advantages, such as being designed as a radiopaque reinforcing element. This allows, for instance, precise placement of the tubular drainage film at the target structure under X-ray imaging guidance.

[0043] The excellent structural integrity of the tubular drainage film can be further enhanced by incorporating a reinforcement zone at at least one end of the film in a circumferential direction. This zone features at least two layers of the drainage film. This is particularly advantageous for applications where aids, such as an absorbent pad, tubing, wire, stent, or introducer, are to be inserted into the tubular drainage film, for example, during surgical procedures or in the production of wound care kits. The reinforcement zone further stabilizes the opening of the tube, allowing any aid to be inserted without risk of tearing.From a manufacturing perspective, it has proven advantageous if the reinforcement area is formed by folding over a section of the tubular drainage film at the end of the tube, particularly an edge region of the tubular drainage film. The folding is carried out in such a way that a tubular element forming the inner boundary surface of the tubular drainage film in the reinforcement area forms the outer boundary surface of the tubular drainage film. The method can further include fixing, for example, spot fixing, the folded-over section of the tubular drainage film, in particular by welding, thermal bonding, an adhesive, and / or a joining agent. "Folding over" includes any shaping, arranging, bending, winding, or other form of folding.To understand folding a drainage film, in which an overlap area, in particular an overlap area that can be connected to a connecting line, and / or a reinforcement area can be achieved with the drainage film.

[0044] The methods according to the invention for producing a tubular drainage film can include rolling up at least one section of the tubular drainage film starting from a tube opening at one end of the tube along a longitudinal tube axis, in particular along a longitudinal tube axis extending from an inner boundary surface towards an outer boundary surface. The tubular drainage film can be rolled up section by section or completely. It has been found that using a rolled-up tubular drainage film is simpler than using unrolled drainage films, since the user can easily unroll the tubular drainage film over structures, for example drainage tubes or probes, to encase them with the tubular drainage film.

[0045] It has proven advantageous, in terms of achieving a smooth surface along the connection line on the outside of the tubular drainage membrane, to completely turn the tubular drainage membrane inside out after joining the seam, particularly if the side of the connection line facing the fold line is turned inside out. A smooth surface on the outside of the connection line ensures high functionality of the tubular drainage membrane in the area of ​​the connection line.

[0046] To achieve particularly good drainage effects with the manufactured tubular drainage film, the drainage film provided in step a) of the inventive method for manufacturing a tubular drainage film can be a drainage film manufactured according to an inventive method for manufacturing a double-walled drainage film. The design of the manufactured drainage film prevents the open drainage space between the two layers from collapsing, supported by the fastening areas. This ensures suction distribution across the entire surface, extending to the edges of the tubular drainage film, and the drainage film effectively transports the exudate away. Tubular drainage film

[0047] According to the invention, the object of the invention is further achieved by a tubular drainage film comprising a first tubular element forming an outer boundary surface and a second tubular element forming an inner boundary surface facing away from the outer boundary surface and connected to the first tubular element by at least one fastening area, wherein the first tubular element and the second tubular element each comprise at least one opening enabling the passage of bodily fluids, and an open drainage space is formed between the outer boundary surface and the inner boundary surface. In the tubular drainage film according to the invention, a capillary effect is achieved between the two tubular elements by means of the open drainage space, which facilitates drainage.The invention enables the suction of body fluids, particularly exudates, across the entire tubular structure. A tubular drainage film according to the invention ensures effective exudate management even of complex wounds, such as wounds located deep within the body, and particularly in endoluminal applications. The tubular drainage film according to the invention has the advantage that it can be applied not only to the surface of wounds but also positioned between organ structures to effectively absorb body fluids, such as exudates.

[0048] The first tubular element and / or the second tubular element may comprise or be a plastic film, wherein the plastic film preferably comprises polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, polyhydroxybutyrate, polylactic acid, and / or cellulose. Such plastic films have the advantage that they effectively prevent the penetration of pathogens, for example, bacteria, and the adhesion and ingrowth of tissue. The plastic film may, in particular, comprise polyethylene, preferably low-density polyethylene (LDPE). It has been found that tubular elements or plastic films containing polyethylene, in particular low-density polyethylene (LDPE), are particularly advantageous for the production and application of tubular drainage films according to the invention.The first tubular element and / or the second tubular element can comprise polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, polyhydroxybutyrate, polylactide, and / or cellulose, preferably polyethylene, more preferably low-density polyethylene (LDPE). The invention further envisages that the tubular elements be provided on one or both sides with an antibacterial or bacteriostatic layer. The antibacterial or bacteriostatic effect can be achieved, for example, by PHMB, silver, chlorhexidine, etc. To prevent the drainage films produced by the inventive method from sticking together, at least one tubular element can have a hydrophilic or hydrophobic finish. Furthermore, the application of swellable materials is also considered.

[0049] For the structural integrity of the tubular drainage membrane, it has proven advantageous for the first and second tubular elements to be connected at a plurality of fastening points, preferably at a plurality of fastening points arranged in a grid pattern. A distance between adjacent fastening points is preferably 2 mm or more, more preferably 3 mm or more, and more preferably 5 mm or more, to ensure excellent capillary action of the open drainage space formed between the first and second tubular elements. The plurality of fastening points can, for example, be arranged in a rectangular grid.

[0050] Furthermore, it has proven advantageous for effective capillary action if the individual fastening areas have an area of ​​5 mm² or less, in particular 3 mm² or less, and especially preferably 2 mm² or less, in a cross-sectional plane extending perpendicular to a radial or depth direction. The depth direction is, in particular, a direction extending perpendicular to the boundary surfaces. The radial direction extends, in particular, perpendicular to the longitudinal axis of the hose.

[0051] Regardless of whether the fastening at the attachment point is achieved by welding (e.g., ultrasonic welding), gluing, or other joining methods, a material bridge connecting the tubular elements can be formed in the attachment areas. It has been found that such a material bridge, which enhances the stability of the overall structure of the tubular drainage membrane, can be produced with particular precision using ultrasonic welding. To maintain the desired capillary action in the drainage space, the distance between the inner boundary surfaces of the tubular elements that define the open drainage space is 5 mm or less, preferably 4 mm or less, and particularly preferably 2 mm or less.The distribution of exudates across the entire surface of the tubular drainage membrane can be ensured by utilizing capillary action within the drainage space if the distance between the inner boundary surfaces of the tubular elements defining the drainage space is 0.05 mm or more, in particular 0.1 mm or more, and most preferably 0.3 mm or more. The tubular drainage membrane preferably exhibits such a distance between the inner boundary surfaces of the tubular elements defining the drainage space over at least 50% of its surface area, and more preferably over at least 70% of its surface area.

[0052] The tubular drainage film according to the invention can have a connection line, preferably a weld seam, which connects the first tubular element and the second tubular element, and / or the first and / or second tubular element and an elastic material. A connection line can be provided, for example, by welding, in particular ultrasonic welding or laser welding, by thermal joining, in particular by UV or hot air, by an adhesive, in particular an adhesive or a hook-and-loop fastener, and / or by a connecting element, in particular a clip.For example, a connecting line can be created by placing a first edge of a drainage film on a second edge of the drainage film and joining them together, for example by ultrasonic welding, thus creating a connecting line between the first edge and the second edge, such as a weld seam.

[0053] It has been found that for the functionality of the tubular drainage film, it is particularly advantageous if the connection line, for example, a weld seam, has a width of 2 mm or less, preferably 1 mm or less, and more preferably 0.5 mm or less, along a circumferential direction of the tubular drainage film. Furthermore, for ensuring functionality across the entire area of ​​the tubular structure, it has proven particularly advantageous if the connection line has a thickness of 1 mm or less, preferably 750 µm or less, and more preferably 450 µm or less, along a radial or depth direction of the tubular drainage film.

[0054] For the application of tubular drainage film in wound care, it has proven particularly advantageous if the drainage film has a basis weight in the range of 30 g / m² to 90 g / m², preferably 40 g / m² to 80 g / m², and more preferably 50 g / m² to 70 g / m². Effective exudate management while simultaneously ensuring the structural integrity of the drainage film can be guaranteed if the drainage film has a tensile strength of 7 N / 25.4 mm or more, an elongation at break of 40% or more, a porosity of 75 m³ / m² / min or more, and / or a bond strength of 0.5 N / 25.4 mm or more. The tensile strength is preferably measured according to DIN EN ISO 527. The tubular drainage membrane can, for example, have a tensile strength of 7 N / 25.4 mm or more, measured according to DIN EN ISO 527. The elongation at break is preferably measured according to DIN EN ISO 527.The tubular drainage membrane can, for example, exhibit an elongation at break of 40% or more, measured according to DIN EN ISO 527. The bond strength is preferably measured in accordance with Edana NWSP 401.0.R0. The tubular drainage membrane can, for example, exhibit a bond strength of 0.5 N / 25.4 mm or more, measured in accordance with Edana NWSP 401.0.R0 or measured according to Edana NWSP 401.0.R0. The porosity is a measure of the ratio of the void volume to the total volume of the drainage membrane.

[0055] The tubular drainage film according to the invention can have a tubular opening at at least one end. For example, a tubular drainage film can be provided that has a tubular opening at one end and has continuous material at the other end of the tubular structure, for example, web-like elements connected by a connecting line and / or tubular elements that form the tubular end. Alternatively, a tubular drainage film can be provided that has a tubular opening at both ends. For some applications, for example, for drainage of deep-lying wounds, it has proven particularly advantageous if the tubular drainage film has a tubular opening at one end and no tubular opening at the other.

[0056] According to the invention, the tubular drainage film can have a reinforcing element, in particular a reinforcing strip or a reinforcing film, at at least one end of the tube and / or along the connection line. A reinforcing strip can, for example, be an area in which a material, such as a double-walled drainage film, in particular a drainage film produced according to the inventive method for producing a double-walled drainage film, is present in two layers, and / or an area in which a reinforcing material, for example a polyethylene film, is attached to the first and / or the second tubular element. It has been found that a film, in particular a polyethylene film, has a particularly advantageous reinforcing effect as a reinforcing element.The structural integrity of the tubular drainage film is particularly enhanced if the connecting line and / or the at least one tube opening has a reinforcing element.

[0057] The excellent structural integrity of the tubular drainage film according to the invention is further enhanced if the tubular drainage film has a reinforcement area at at least one end, in which the drainage film is at least double-layered. This is particularly advantageous for applications where aids, such as an absorbent material, tubing, wire, stent, or insertion aid, are to be inserted into the tubular drainage film. The reinforcement area further stabilizes the opening of the tubing, allowing any aids to be inserted into the tubular drainage film without the risk of tearing.From a manufacturing perspective, it has proven advantageous if the reinforcement area is designed as a double-layered edge formed by folding over a section of the tubular drainage film at the end of the tube, the folding being carried out in such a way that the second tubular element forming the inner boundary surface in the reinforcement area forms the outer boundary surface of the tubular drainage film, in particular the outer boundary surface of the reinforcement area of ​​the tubular drainage film. The folded edge can be fixed at specific points.

[0058] According to the invention, the outer boundary surface of the tubular drainage film, the inner boundary surface of the tubular drainage film, and / or an inner lumen of the tubular drainage film enclosed by the inner boundary surface of the tubular drainage film can include a sliding aid and / or an insertion aid. Such sliding aids and / or insertion aids can further increase ease of use and user comfort. For example, an outer boundary surface and / or an inner boundary surface of the tubular drainage film can be designed with a low-friction surface, in particular with a non-stick coating and / or a micro-rough surface, to facilitate insertion.In particular, the outer and / or inner boundary surface of the tubular drainage film may include or be coated with silicone, polytetrafluoroethylene (PTFE), and / or moisture to facilitate insertion. Lubricating agents that significantly enhance lubricity include, for example, a water-based lubricant, a glycerol-based lubricant, a polymeric gel (especially an anti-allergenic polymeric gel), an endoscopic lubricant (especially an endoscopic lubricating gel), and / or an aqueous solution (especially a sodium chloride solution). It is particularly advantageous if the substances used as lubricating agents dissolve completely, especially in an aqueous solution, to prevent any residue from remaining on the product. Insertion aids that include a textile and / or a plastic component are particularly suitable.The insertion aids may comprise a low-friction surface, in particular a non-stick coating and / or a micro-rough surface. For example, the insertion aid may comprise a textile and / or a plastic, wherein the textile or plastic comprises or is coated with silicone, polytetrafluoroethylene (PTFE), and / or moisture. The insertion aid may be a tubular insertion aid arranged within the inner lumen of the tubular drainage film, for example, a tubular insertion aid having one or two tubular openings. In particular, the insertion aid may have a tubular opening at one end of the tubular tube and a closed end at the other. A tubular insertion aid may be designed with a predetermined breaking point at one of the closed tubular ends.The tubular drainage membrane can be provided in single-lumen or multi-lumen versions.

[0059] To make the tubular drainage film particularly advantageous for a variety of applications, such as endoluminal applications, applications in gynecology or urology, and applications in thoracic, visceral, and / or hip surgery, the tubular drainage film can have a length ranging from 0.5 cm to 40 cm, preferably 2 cm to 30 cm, and more preferably 5 cm to 20 cm. However, longer or shorter tubular drainage films can also be provided. For example, tubular drainage films with a length of 10 cm or more, or 20 cm or more, are suitable for intraluminal applications in the gastrointestinal tract and for fistulas.When used in various wound cavities, the length can be adapted to the wound cavity; for example, tubular drainage films with a length of 10 cm or less can be provided for wound cavities, or for smaller wound cavities with lengths of 5 cm or less, for example 2 cm or less.

[0060] Furthermore, the tubular drainage film is particularly suitable for a variety of applications in the context of effective wound management when it has an outer diameter in the range of 1 mm to 60 mm, preferably 2 mm to 50 mm, and more preferably 4 mm to 30 mm. However, tubular drainage films with larger or smaller outer diameters can also be provided. For applications involving narrow wounds and / or deep body regions, such as the pancreas, gynecological or urological applications, and endoluminal applications, a tubular drainage film with a small outer diameter is particularly suitable, for example, tubular drainage films with an outer diameter of 5 mm or less, and in particular 4 mm or less.The tubular drainage film according to the invention has the advantage that even with a small outer diameter, a uniform drainage performance is ensured and tissue blockage of the drainage flow is prevented. The tubular drainage film thus enables active drainage of fluids even with a very small outer diameter. In invasive surgery, e.g., on the hip, particularly in large wound areas, tubular drainage films with a larger outer diameter can also be used, for example, with an outer diameter of 6 mm or more. Depending on the accessibility and size of the wound area, a tubular drainage film of suitable length and outer diameter can be provided. Wound care kit

[0061] The object of the invention is further achieved by a wound care kit according to the invention, which comprises a tubular drainage film produced according to the inventive method for producing a tubular drainage film, or the tubular drainage film according to the invention, and at least one further component, for example selected from an absorbent body, a tube, a wire, a stent, and an insertion aid. For the sake of particularly easy handling of the wound care kit, it has proven advantageous if at least one section of the at least one further component is arranged in an inner lumen of the tubular drainage film enclosed by an inner boundary surface.For particularly efficient negative pressure wound therapy, the wound care kit can, for example, include a tubular drainage film and a drainage tube, with a section of the drainage tube positioned within an inner lumen of the tubular drainage film. The drainage tube can be connected to a negative pressure source. At least one other component can be partially or completely integrated within the tubular drainage film.

[0062] In a particularly preferred embodiment of the invention, the absorbent material is a sponge, foam, in particular polyurethane or polyvinyl alcohol foam, or gauze. It has been found that a wound care kit with such an absorbent material enables efficient aspiration of fluids from body regions, especially wound areas. Tissue adhesion to the absorbent material is prevented when the absorbent material is arranged in the inner lumen of the tubular drainage film, which is enclosed by an inner boundary surface. Fluids can thus be aspirated efficiently and atraumatically from wound areas.

[0063] For optimal suction efficiency, it has proven advantageous for a wound care kit to include a drainage tube. The drainage tube can be single-lumen or multi-lumen. A wound care kit with a drainage tube allows for the continuous suction of fluids from the wound area and also enables the suction of large volumes of fluid. Because the tubular drainage film can be supplied in any dimension, particularly with any outer diameter, length, and shape, the wound care kit can even be supplied with and / or used with tubes that have complex geometries, such as multi-lumen configurations.

[0064] The wound care kit according to the invention can have a length ranging from 0.5 cm to 250 cm, preferably from 10 cm to 200 cm. The length of the wound care kit can be optimized for the specific application; for example, a wound care kit with a length of at least 10 cm or at least 20 cm can be provided for intraluminal applications in the gastrointestinal tract or for use in fistulas. For use in wound cavities, the length can be adapted to the specific wound cavity; for example, depending on the size or depth of the wound cavity, the wound care kit can have a length of less than 10 cm, less than 5 cm, or less than 2 cm. Medical uses and procedures for wound care

[0065] The invention further relates to the tubular drainage film according to the invention for use in wound care and the wound care kit according to the invention for use in wound care, for example, for draining a wound and / or for use in a method according to the invention for treating a wound. The tubular drainage film and the wound care kit are preferably used for drainage, for example, during surgical operations and / or postoperatively. The tubular drainage film and the wound care kit according to the invention are preferably used for draining bodily fluids from wound areas, for example, during operations. The tubular drainage film and the wound care kit according to the invention enable simple and safe aspiration of fluids from a wound.The tubular drainage film and the wound care kit according to the invention can be used, for example, endoluminally in the gastrointestinal tract, in gynecology and urology, during surgical procedures, such as thoracic, visceral, and hip surgery, and in negative pressure wound therapy. The tubular drainage film and the wound care kit can be used for drainage, particularly during surgery. During a surgical procedure, blood, wound secretions, and / or tissue fluid typically accumulate, and the drainage system can prevent this accumulation in the wound cavity. This significantly facilitates the healing process.

[0066] The tubular drainage film or wound care kit according to the invention can be used to particular advantage in combination with negative pressure wound therapy for wound care. The tubular drainage film or wound care kit according to the invention is used as a direct interface between the wound, in particular the wound bed, and a wound filler or an area of ​​exudate removal, for example, a drainage tube. The tubular drainage film or wound care kit according to the invention is particularly advantageous for use on wounds of internal organs. The tubular drainage film is applied to the wound, providing a drainage function and a very smooth surface to prevent adhesion or friction between the tissue and the film.The wound care kit can be anatomically pre-shaped or cut to size to suit specific requirements. When used in combination with negative pressure wound therapy, the tubular drainage film or wound care kit according to the invention can be filled with a filling medium such as gauze or foam and / or a drainage tube can be inserted. The tube used for draining exudate or wound drainage can be led out of the body, for example, the abdominal cavity, and connected to a negative pressure source, which can be provided by a pump or, in a hospital setting, by a central system. The negative pressure source then allows the exudate to be removed from the wound via the tubular drainage film or wound care kit according to the invention, thus achieving effective exudate management.

[0067] The following advantages arise from the medical use of the tubular drainage film or wound care kit according to the invention: The openings that allow bodily fluids to pass through support the removal of exudate and prevent it from flowing back into the wound (capillary action). The tubular drainage film prevents tissue or cells from adhering to the wound bed or surrounding organs. The tubular drainage film or wound care kit can be cut to any size or structure of the wound area without impairing its drainage function, thus enabling the treatment of even complex wounds.

[0068] The invention is explained below with reference to the drawing, to which express reference is made with regard to all details essential to the invention and not further detailed in the description. The drawing shows: Fig. 1 a schematic representation of an ultrasonic welding device Fig. 2 a schematic representation of a punching device Fig. 3 a schematic representation of a device for turning inside out the tubular drainage film Fig. 4 a schematic representation of a folding technique or winding technique for folding, in particular folding the drainage film around a folding line, or for winding the drainage film around a winding axis such that the drainage film has an overlap area that can be joined to form a connecting line Fig. 5 A schematic representation of a self-adhesive drainage film, which can be used as a tubular drainage film by wrapping or folding. Fig. 6 A schematic representation of a self-adhesive drainage film, which can be used as a tubular drainage film by wrapping or folding it, for example around a drainage hose. Fig. 7a schematic representation of a connecting line, in particular a weld seam Fig. 8 a schematic representation of attaching a reinforcement element to the drainage membrane Fig. 9 a schematic representation of an insertion aid Fig. 10 a schematic representation of a rolled-up tubular drainage film and a rolled-up tubular drainage film Fig. 11 a schematic representation of a tubular drainage film made of elastic material Fig. 12 A schematic representation of a tubular drainage film with an edge reinforced by folding over. Fig. 13 Schematic representations of tubular drainage films Fig. 14 a schematic representation of a tubular drainage film with hose Fig. 15 a schematic representation of a tubular drainage film with tube and absorbent body Fig. 16A schematic representation of a coiled, tubular drainage film with a hose.

[0069] The in Fig. 1The ultrasonic welding device shown can be used to produce the tubular drainage film 3a according to the invention. For example, the ultrasonic welding device can be used to produce a tubular drainage film 3a by simultaneously punching and welding; in this process, the overlapping material in the overlap area is joined to form a connecting line 11 by ultrasonic welding, and at the same time an edge strip of residual material is removed. The double-walled drainage film 3b is folded over, placed in the foundation 4, and fixed. The ultrasonic welding die 1, for example an L-shaped ultrasonic welding die 1, is located in the bracket 2 positioned above the foundation 4. A generator induces the required voltage in the welding die 1. The welding die 1 moves downwards and welds the contour of the tubular drainage film 3a.Once the welding process is complete, the bracket 2 returns to its starting position. The tubular drainage film 3a can then be removed. The left illustration shows a top view of the ultrasonic welding device, and the right illustration shows a side view.

[0070] The in Fig. 2The illustrated die-cutting device can be used to produce the drainage film 3 according to the invention. A provided double-walled drainage film 3b is folded over on one side and inserted into the lower half of the die-cutting tool. A cutting tool with integrated heating is located in the lower half of the die-cutting tool. The die-cutting process is started by lowering the upper half of the die. In the same process, the warm and sharp cutting element 5 welds and separates the drainage film 3b at the cutting edge, resulting in a tubular drainage film 3a with a weld seam 6. The remaining film 7 is removed by the die-cutting process. The die is then opened by raising the upper half of the die, and the tubular drainage film 3a can be removed.

[0071] The in Fig. 3The illustrated device can be used to turn the tubular drainage film 3a inside out. First, the tubular drainage film 3a is manufactured using one of the methods mentioned, for example, by welding the overlap area to form a connecting line 11. For use in the wound area, particularly to prevent tissue adhesion, it has proven especially advantageous if the connecting line 11 on the outside of the tubular drainage film 3a has a smooth surface. To create a smooth surface at the weld seam 6, the tubular drainage film 3a can be turned inside out such that the side 10 of the connecting line 11, which previously faced away from the fold line, lies on the side 12 of the connecting line 11 facing the fold line after turning. The tubular drainage film 3a can be turned inside out.The tubular drainage film 3a is turned inside out over the upper movable plunger 8 of the illustrated device. A sleeve 9 additionally moves over the movable plunger 8 and, with the aid of the rigid counter-plunger 13, turns the tubular drainage film 3a inside out.

[0072] The in Fig. 4The illustrated folding or winding technique can be used to wrap a drainage film 3 flat around a winding axis 27, for example over the tip of a tube 16, or to fold it over a tube 16. For example, the drainage film 3 can be wound around a winding axis 27 in such a way that the drainage film 3 has an overlap area formed by the winding around the winding axis 27, which can be joined to form a connecting line 11, in which the drainage film 3 is at least double-layered. The overlap area can then be joined or fixed to obtain a tubular drainage film 3a, for example by an adhesive 14 or a connecting element such as a clamp, seam, or an annular application aid.

[0073] The in Fig. 5The illustrated self-adhesive drainage film 3 can be attached to any structure, for example, body parts, surgical instruments, absorbent pads, tubes, wires, stents, introducer devices 22, and / or devices for negative pressure wound therapy. An adhesive 14 attached to the drainage film 3, in particular an adhesive, an adhesive material, and / or a hook-and-loop fastener 15, such as one or more barbs, can be used to allow the drainage film 3 to be wrapped or folded around other structures and then, in particular, attached to or around the structure in a tubular form. Such a drainage film 3 can be used as a self-adhesive tubular drainage film 3a and has the advantage that it can be adapted in situ to the structural requirements, for example, the size of the wound cavity. During the wrapping or folding process, the drainage film 3 can be folded or folded around the structure.By folding the drainage film 3 around the corresponding structure, for example around a drainage tube, the adhesive section of the drainage film 3 can be attached to another section of the drainage film 3. If the drainage film 3, thus fixed to a structure, must withstand particularly high mechanical loads, it can be additionally secured by means of a seam if necessary. According to the invention, the drainage film 3 can be provided with one or more adhesive sections; in particular, the adhesive 14 can be applied to one section, or the adhesive 14, for example the two complementary components of a hook and loop fastener 15a, 15b, can be applied to two or more sections, which can thereby be attached to one another.

[0074] Fig. 6Figure 1 shows a self-adhesive drainage film 3 with an adhesive agent 14, which can be wrapped around a hose 16 or a probe and can thus be used as a tubular drainage film 3a.

[0075] Fig. 7 Figure 1 shows a schematic representation of a connection line 11, in particular a weld seam 6, between a first element 17 and a second element 18, for example, a first and second sheet-like element or a first and second tubular element. Detail A shows a reduction in film thickness due to the joining process, in particular a welding operation. The film is compressed in the area of ​​the connection line 11, in particular the weld seam 6. The compression of the double-walled drainage film 3b in the area of ​​the connection line 11 and the cutting wheel angle create a geometry-related angle α between the ridge of the connection line 11 and the outer boundary surface 28 of the tubular drainage film 3a.

[0076] A connection line 11, for example a weld seam 6, of a perforated drainage film 3 can represent a critical point of the product with regard to film stability. In order to equip the tubular drainage film 3a according to the invention with open drainage space 20 with particularly excellent strength properties, in particular to improve the strength of a connection line 11 such as a weld seam 6, it can be reinforced with additional material. Fig. 8Figure 1 shows a schematic representation of such an attachment of a reinforcing element 29 to the drainage film 3 comprising the first element 17 and the second element 18, for example by welding with a cutting wheel 19. A polyethylene film, particularly non-perforated, can be used as the additional material or reinforcing element 29. To enable particularly effective welding of the additional film layer, for example, the additional non-perforated polyethylene film, to the drainage film 3, the film layer can be made of polyethylene. Due to the additionally welded, particularly non-perforated, polyethylene film, more material flows into the holes of the drainage film 3 in the area of ​​the connection line 11, for example during welding, thus stabilizing it and achieving excellent strength.Such a reinforcing element 29, for example a polyethylene film, significantly increases the tensile strength of the weld 6. To attach the reinforcing element 29, it can be placed over the drainage film 3 and then folded over. During the joining process, for example by ultrasonic welding, the reinforcing element 29 bonds with the drainage film 3 in the overlap area, creating a connection line 11, in particular a stable weld 6. The remaining material 21 of the reinforcing element 29, for example remaining polyethylene film, can then be removed in the area of ​​the connection line 11, in particular in the area of ​​the weld 6, e.g. manually or mechanically. The reinforcing element 29, for example a polyethylene film, can be supplied in such a way that it is only present in the connection line 11, in particular in the weld 6.

[0077] The in Fig. 9 The tubular drainage film 3a shown, with insertion aid 22, simplifies the application of the drainage film 3. Various materials such as textiles or plastics that exhibit low friction against plastics, e.g., micro-rough textiles, can be used as the insertion aid 22. The insertion aid 22 can be applied to the tube 16 ( Fig. 9 left) or be integrated directly into the drainage film 3a or be enclosed in an inner lumen of the tubular drainage film 3a ( Fig. 9 (right). For example, the insertion aid 22 can be slipped over a tube, such as a drainage tube or a probe ( Fig. 9(left). The tubular drainage film 3a can, for example, have a closed end if a hose 16 is to be encased with the tubular drainage film 3a. For some applications, it has proven advantageous if such a closed end is provided with a predetermined breaking point 23. The insertion aid 22 can be removed after application by applying force through the predetermined breaking point 23. The insertion aid 22 can also be tubular with two open ends ( Fig. 9(right). From a manufacturing perspective, it has proven particularly advantageous if the insertion aid 22 is already incorporated into the tubular drainage film 3a during its production. For ease of handling, it has proven beneficial if the insertion aid 22 is longer than the tubular drainage film 3a, so that it protrudes from one end of the tubular drainage film 3a and is easily accessible. After inserting the tubular drainage film 3a, or a tube encased in a tubular drainage film 3a, into the wound area, the insertion aid 22 can be removed by simply pulling it out.

[0078] In Fig. 10The process of rolling up the tubular drainage film 3a to obtain a rolled-up tubular drainage film 3a is shown. Sectionally or fully rolled tubular drainage films 3a have the advantage of being efficiently packaged, particularly in an environmentally friendly manner due to material savings. Furthermore, they offer the advantage that the user can easily unroll the tubular drainage film 3a over structures, such as hoses 16, especially drainage hoses or probes, to encase them. To roll up the tubular drainage film 3a, a section of the tubular drainage film 3a or the entire tubular drainage film 3a can be rolled up from a hose opening at one hose end along a longitudinal hose axis 30.In particular, the tubular drainage film 3a can be rolled up along the longitudinal tube axis 30 starting from an inner boundary surface towards an outer boundary surface 28 in order to roll up a section or the entire tubular drainage film 3a.

[0079] In Fig. 11A tubular drainage film 3a with elastic material is shown. The tubular drainage film 3a can, for example, have an elastic film 24 or an elastic seam 25, in particular a seam made of an elastic material. By integrating an elastic material into a tubular drainage film 3a, the elasticity of the tubular drainage film 3a can be increased, especially if the double-walled drainage film 3b used to form the tubular drainage film 3a is made of a material with low elasticity. A tubular drainage film 3a with elastic material can be formed by joining a double-walled drainage film 3b and an elastic material along an overlap area between the drainage film 3b and the elastic material.By integrating the elastic material, for example a strip of elastic film 24 or an elastic seam 25, the tubular drainage film 3a becomes particularly stretchable, which facilitates its application, for example, applying it to a drainage tube.

[0080] In Fig. 12Figure 1 shows a side view of a tubular drainage film 3a with a reinforced edge formed by folding over. The tubular drainage film 3a can be provided with a reinforcement area at one or both ends in a circumferential direction. From a manufacturing perspective, it has proven particularly efficient to form the reinforcement area by folding over a section of the tubular drainage film 3a at the end of the tube. This folding is carried out in such a way that a tubular element forming the inner boundary surface of the tubular drainage film 3a within the reinforcement area forms the outer boundary surface 28 of the tubular drainage film 3a. The marked edge region 26 of the tube opening can be folded outwards to provide a double-walled and thus reinforced edge of the tubular drainage film 3a.The folded-over edge can be secured at specific points, for example with a seam. The reinforced edge effectively prevents the tubular drainage film 3a from tearing.

[0081] In Fig. 13 Various embodiments of the tubular drainage film 3a according to the invention are shown. In particular, the tubular drainage film 3a can have a tubular opening 32 or an open tubular end at one end and a closed tubular end 33 at the other end. The tubular drainage film 3a can also have a tubular opening 32 at both ends. Furthermore, the tubular drainage film 3a can have a reinforcing element 29, for example, a folded-over edge.

[0082] Fig. 14 shows a side view of a tubular drainage film 3a with tube 16, which together can be provided as a wound care kit 34. Fig. 15shows a side view of a tubular drainage film 3a with tube 16 and absorbent body 35, which together can be provided as a wound care kit 34. Fig. 16 shows a side view of a drainage film 3, for example a tubular drainage film 3a, with tube 16 and connecting device 36, for example a ring-shaped application aid or clamp, which together may be provided as a wound care kit 34. Reference symbol list

[0083] 1 Welding mold 2 Bracket 3 Drainage film 3a Tubular drainage film 3b Double-walled drainage film 4 Foundation 5 Cutting element 6 Weld seam 7 Film remnant 8 Plunger 9 Sleeve 10 Side of the connection line away from the folding line, in particular the fold line 11 Connection line 12 Side of the connection line towards the folding line, in particular the fold line 13 Counter plunger 14 Adhesive 15 Hook and loop fastener 15a, 15b Hook and loop fastener 16 Tube 17 First element 18 Second element 19 Cutting wheel 20 Drainage space 21 Remaining material 22 Insertion aid 23 Break point 24 Elastic film 25 Elastic seam 26 Edge area 27 Winding axis 28 Outer boundary surface of the tubular drainage film 29 Reinforcement element 30 Hose axis 31 Inner boundary surface of the tubular drainage film 32 Hose opening 33 Closed hose end 34 Wound care kit 35 Absorbent core 36 Connecting element

Claims

1. Method for producing a double-walled drainage film (3b) with an open drainage space, comprising the following steps: i) providing a first web-shaped element and a second web-shaped element; ii) perforating the first web-shaped element and the second web-shaped element, wherein at least one opening allowing the passage of bodily fluids, preferably a plurality of openings allowing the passage of bodily fluids, is formed in each of the first web-shaped element and the second web-shaped element; iii) arranging the first web-shaped element on the second web-shaped element such that the first web-shaped element and the second web-shaped element are arranged approximately parallel; iv) connecting the first web-shaped element and the second web-shaped element at at least one fastening region, in particular at at least one punctiform fastening region, preferably by ultrasonic welding, to obtain a double-walled drainage film (3b) with an open drainage space formed between the first web-shaped element and the second web-shaped element, characterized in that the method comprises forming a tubular structure from the drainage film (3, 3a, 3b).

2. Method according to Claim 1, characterized in that the at least one opening allowing the passage of bodily fluids has a diameter in a range from 100 µm to 2000 µm, preferably in a range from 300 µm to 700 µm, more preferably in a range from 400 µm to 600 µm, and / or characterized in that the first web-shaped element and the second web-shaped element are connected in step iv) at a plurality of fastening regions, preferably at a plurality of fastening regions formed in a grid arrangement; wherein, preferably, a distance between in each case adjacent fastening regions is 2 mm or more, preferably 3 mm or more, more preferably 5 mm or more, and / or characterized in that the at least one opening allowing the passage of bodily fluids has a round, circular and / or oval shape, in particular in relation to a plan view of a planar extent of the first or second web-shaped element.

3. Method according to one of the preceding claims, characterized in that step ii) is carried out before or after step iii), and / or step iv) is carried out after step iii) and before or after step ii).

4. Method for producing a tubular drainage film (3a), characterized in that the method comprises the following steps: a) providing a drainage film (3, 3a, 3b) produced according to one of Claims 1 to 3; b) turning, in particular folding, the drainage film (3, 3a, 3b) onto itself about a turning line, in particular folding line, such that the drainage film (3, 3a, 3b) has an overlapping region which can be connected to form a connecting line (11); wherein, preferably, the drainage film (3, 3a, 3b) has a first edge and a second edge running substantially parallel to the first edge, and the drainage film (3, 3a, 3b) is turned or folded onto itself along the turning or folding line such that the drainage film (3, 3a, 3b) has the overlapping region which can be connected to form the connecting line (11) along the first edge and the second edge; c) connecting the drainage film (3, 3a, 3b) along the overlapping region, wherein a connecting line (11) is formed; d) obtaining a tubular drainage film (3a).

5. Method for producing a tubular drainage film (3a), characterized in that the method comprises the following steps: a) providing a drainage film (3, 3a, 3b) produced according to one of Claims 1 to 3, and an elastic material; b) arranging a first edge of the drainage film (3, 3a, 3b) on the elastic material such that an overlapping region which can be connected to form a connecting line (11) is formed between the first edge of the drainage film (3, 3a, 3b) and the elastic material; c) connecting the drainage film (3, 3a, 3b) and the elastic material along the overlapping region between the first edge of the drainage film (3, 3a, 3b) and the elastic material, wherein a connecting line (11) is formed; d) turning, in particular folding, the drainage film (3, 3a, 3b) onto the elastic material with respect to a turning line, in particular a folding line, such that an overlapping region which can be connected to form a connecting line (11) is formed between a second edge of the drainage film (3, 3a, 3b), preferably a second edge of the drainage film (3, 3a, 3b) running substantially parallel to the first edge, and the elastic material; e) connecting the drainage film (3, 3a, 3b) and the elastic material along the overlapping region between the second edge of the drainage film (3, 3a, 3b) and the elastic material, wherein a connecting line (11) is formed; f) obtaining a tubular drainage film (3a).

6. Method for producing a tubular drainage film (3a), characterized in that the method comprises the following steps: a) providing a drainage film (3, 3a, 3b) produced according to one of Claims 1 to 3; b) winding the drainage film (3, 3a, 3b) about a winding axis (8, 27) such that the drainage film (3, 3a, 3b) has an overlapping region which is formed by the winding about the winding axis (8, 27) and can be connected to form a connecting line (11) and in which the drainage film (3, 3a, 3b) is at least double-layered; c) connecting a first layer and a second layer of the drainage film (3, 3a, 3b) which is at least double-layered in the overlapping region, preferably by an adhesive (14) or a connecting means (36); wherein, preferably, a connecting line (11) is formed; d) obtaining a tubular drainage film (3a).

7. Method according to one of Claims 4 - 6, characterized in that the connection is carried out by welding, in particular ultrasonic welding or laser welding, by thermal connection, in particular by means of UV or hot air, by an adhesive (14), in particular an adhesive or a Velcro connection means (15, 15a, 15b), and / or by a connecting means, in particular a clamp.

8. Method according to one of Claims 4 - 7, characterized in that the connection comprises: arranging the drainage film (3, 3a, 3b) in an ultrasonic welding device and welding the drainage film (3, 3a, 3b), in particular by means of a welding die (1), for example an L-shaped welding die, to form a tubular drainage film (3a).

9. Method according to one of Claims 4 - 6 and 7 - 8, characterized in that an edge strip of the drainage film (3, 3a, 3b) arranged on a side of the connecting line (11) facing away from the turning line, in particular folding line, is removed during the connection or after the connection, in particular by punching.

10. Method according to one of Claims 4 - 9, characterized in that the method comprises attaching a reinforcing element (0, 29), in particular a reinforcing strip or a reinforcing film, in a region of the connecting line (11), preferably by arranging the reinforcing element (0, 29) in the overlapping region before the connection, and / or at at least one tube end (4, 33), preferably characterized in that the reinforcing element (0, 29) is a film, preferably a polyethylene film (24).

11. Method according to one of Claims 4 - 10, characterized in that the tubular drainage film (3a) is formed at at least one tube end (4, 33) in a circumferential direction with a reinforcing region in which the drainage film (3, 3a, 3b) is at least double-layered; wherein the reinforcing region is preferably formed by turning a section of the tubular drainage film (3a) at the tube end (4, 33), wherein the turning is carried out in particular such that a tubular element forming the inner boundary surface forms the outer boundary surface (28) of the tubular drainage film (3a) in the reinforcing region.

12. Method according to one of Claims 4 - 11, characterized in that at least one section of the tubular drainage film (3a) is rolled up starting from a tube opening (32) at a tube end (4, 33) along a longitudinal tube axis (30), in particular is rolled up along a longitudinal tube axis (30) starting from an inner boundary surface in the direction of an outer boundary surface (28).

13. Method according to one of Claims 4 - 5 and 7 - 12, characterized in that, after the connection, a side of the connecting line (11) facing the turning line, in particular folding line, is rotated completely outwards by turning the tubular drainage film (3a).

14. Method according to one of Claims 4 - 13, characterized in that the drainage film (3, 3a, 3b) provided in step a) is a drainage film (3, 3a, 3b) produced according to one of Claims 1 to 5.

15. Tubular drainage film (3a) comprising a first tubular element forming an outer boundary surface (28) and a second tubular element forming an inner boundary surface facing away from the outer boundary surface (28) and connected to the first tubular element by at least one fastening region; wherein the first tubular element and the second tubular element each comprise at least one opening allowing the passage of bodily fluids and an open drainage space is formed between the outer boundary surface (28) and the inner boundary surface.

16. Tubular drainage film (3a) according to Claim 15, characterized in that the first tubular element and / or the second tubular element is / are a plastics film; wherein the plastics film preferably comprises polyethylene, polypropylene, polyethylene terephthalate, polyurethane, polytetrafluoroethylene, polyhydroxybutyrate, polylactide and / or cellulose.

17. Tubular drainage film (3a) according to Claim 15 or 16, characterized in that the first tubular element and the second tubular element are connected at a plurality of fastening regions, preferably at a plurality of fastening regions formed in a grid arrangement; wherein, preferably, a distance between adjacent fastening regions is 2 mm or more, preferably 3 mm or more, more preferably 5 mm or more.

18. Tubular drainage film (3a) according to one of Claims 15 to 17, characterized in that the tubular drainage film (3a) has a connecting line (11), preferably a weld seam (6), which connects the first tubular element and the second tubular element, and / or the first and / or second tubular element and an elastic material, preferably characterized in that the connecting line (11) has a width of 2 mm or less, preferably 1 mm or less, more preferably 0.5 mm or less, along a circumferential direction of the tubular drainage film (3a).

19. Tubular drainage film (3a) according to Claim 18, characterized in that the connecting line (11) has a thickness of 1 mm or less, preferably 750 µm or less, more preferably 450 µm or less, along a radial direction of the tubular drainage film (3a).

20. Tubular drainage film (3a) according to one of Claims 15 - 19, characterized in that the tubular drainage film (3a) has a basis weight in a range from 10 g / m2 to 200 g / m2, preferably 40 g / m2 to 80 g / m2, more preferably 50 g / m2 to 70 g / m2.

21. Tubular drainage film (3a) according to one of Claims 15 - 20, characterized in that the tubular drainage film (3a) has a tensile strength of 7 N / 25.4 mm or more, an elongation at break of 40% or more, a porosity of 75 m3 / m2 / min or more, and / or a bond strength of 0.5 N / 25.4 mm or more.

22. Tubular drainage film (3a) according to one of Claims 15 - 21, characterized in that the tubular drainage film (3a) has a tube opening (32) at at least one tube end (4, 33); wherein, preferably, the tubular drainage film (3a) has a tube opening (32) at one tube end (4, 33) and no tube opening (32) at another tube end.

23. Tubular drainage film (3a) according to one of Claims 15 - 22, characterized in that the tubular drainage film (3a) has a reinforcing element (0, 29), in particular a reinforcing strip or a reinforcing film, at at least one tube end (4, 33) and / or along the connecting line (11).

24. Tubular drainage film (3a) according to one of Claims 15 - 23, characterized in that the tubular drainage film (3a) has a reinforcing region at at least one tube end (4, 33) in which the drainage film (3, 3a, 3b) is at least double-layered; wherein the reinforcing region is preferably formed in the form of a double-layered edge which is formed by turning a section of the tubular drainage film (3a) at the tube end (4, 33), wherein the turning is carried out in particular such that the second tubular element forming the inner boundary surface forms the outer boundary surface (28) of the tubular drainage film (3a), in particular the outer boundary surface (28) of the reinforcing region of the tubular drainage film (3a), in the reinforcing region.

25. Tubular drainage film (3a) according to one of Claims 15 - 24, characterized in that the outer boundary surface (28), the inner boundary surface and / or an inner lumen of the tubular drainage film (3a) comprised by the inner boundary surface comprise / comprises a sliding aid and / or an insertion aid (22), preferably characterized in that the sliding aid comprises a waterbased lubricant, a glycerol-based lubricant, a polymeric gel, in particular an antiallergenic polymeric gel, an endoscopic lubricant, in particular an endoscopic sliding gel, and / or an aqueous solution, in particular a sodium chloride solution.

26. Tubular drainage film (3a) according to Claim 25, characterized in that the insertion aid (22) comprises a textile and / or a plastic; and / or in that the insertion aid (22) is a tubular insertion aid (22) arranged in the inner lumen of the tubular drainage film (3a).

27. Wound care kit comprising a tubular drainage film (3a) produced according to one of Claims 4 to 15 or a tubular drainage film (3a) according to one of Claims 17 to 27, and at least one further constituent, selected from an absorption body (35), a tube (7, 16), a wire, a stent and an insertion aid (22); wherein, preferably, at least one section of the at least one further constituent is arranged in an inner lumen, comprised by an inner boundary surface, of the tubular drainage film (3a).