Method and device for producing a foil-covered workpiece

Abstract

The present invention relates to a method for producing a foil-covered workpiece, a foil-covered workpiece producible using the method according to the invention, a system comprising at least one foil-covered workpiece, and a device (100) for producing a foil-covered workpiece.

Description

[0001] DESCRIPTION

[0002] Method and device for producing a foil-coated workpiece

[0003] The present invention relates to a method for producing a foil-covered workpiece, a foil-covered workpiece that can be produced by the method according to the invention, a system comprising at least one foil-covered workpiece, and a device for producing a foil-covered workpiece.

[0004] Multiwell plates are used in research and industry to conduct many cell biological, microbiological, and biochemical experiments. Multiwell plates are characterized in particular by their large number of regularly arranged wells. To cover the widest possible range of applications, a wide variety of such plates are offered. Plate formats with 6 (2 x 3 matrix) to 96 (8 x 12 matrix) wells are particularly commonly used in cell biology. For biochemical tests, larger format plates, such as plates with 384 wells (16 x 24 matrix) or more, are often used. The arrangement of the individual wells of the multiwell plates relative to one another, their external and internal dimensions, as well as the dimensions of the plates themselves, have now been standardized (ANSI standards).This allows for easy automation of experimental procedures, for example, through the use of pipetting robots, the reading of measurement results using a plate reader, and / or automated microscopy. Furthermore, standardization allows the use of different inserts and attachments for the various multiwell plates available on the market.

[0005] A special application for multiwell plates is the use of plates with film bottoms, especially with membrane bottoms. The membrane bottoms can be used to create separate reaction spaces (compartmentalization), for filtration (separation of solid and liquid components), or as a surface for the adhesion of cells, chemical molecules, or biomolecules. The membrane bottom plates used for this purpose are characterized by the fact that they comprise a large number of wells, the bottom of each of which has a porous, impermeable, semipermeable, or permeable barrier layer, in particular a membrane. This barrier layer, in particular a membrane, can, for example, allow the selective passage of ions or organic molecules, such as certain active ingredients, or biomolecules, such as growth factors, peptides, proteins, hormones, or enzymes.

[0006] Membrane bottom plates are traditionally used as cell culture inserts to address complex questions in cell and tissue culture. Applications for such cell culture inserts include migration or invasion studies, transport assays, co-cultures, or the cultivation of complex three-dimensional tissue structures, such as epithelial or skin cells, including in so-called air-liquid interface (ALI) cultures. The resulting tissue structures can be used in subsequent biological tests, such as toxicological ones, or in physical test systems, such as transepithelial / transendothelial electrical resistance (TEER) or impedance measurements.

[0007] In the simplest case, membrane bottom plates are used for filtration applications. The membrane at the bottom of each well serves to separate the solid components of a sample from the liquid components. For this purpose, a membrane with a pore size is selected that retains solid components exceeding a certain hydrodynamic diameter while allowing the passage of liquids and solid components with a smaller hydrodynamic diameter.

[0008] When using membrane bottom plates, it is particularly important to ensure that no cross-contamination can occur between the samples or between the different chambers of the individual wells of the membrane bottom plate. For example, if the bottoms of the individual wells of the membrane bottom plate are formed by a single, continuous permeable membrane, this membrane provides a connection between the wells, making cross-contamination possible via capillary forces.

[0009] The production of membrane bottom plates usually takes place in two steps. In a first step, a membrane and a multiwell plate are prepared, with each well of the multiwell plate having at least one opening at the bottom. In a next step, the membrane is connected to the multiwell plate so that the at least one opening at the bottom of each well is closed by the membrane. Various methods are available for connecting the membrane material to the multiwell plate material. For example, adhesives could be used to connect the membrane to the bottom of the wells of a multiwell plate. Another option is to join the components together using ultrasonic welding. Especially when handling biological samples, it is desirable for the components to be joined as solvent-free and residue-free as possible.

[0010] A method for bonding a polymer film to a cell cultivation device is disclosed in EP 2 611 539 B1. The bond between the cell cultivation device and the polymer film is achieved according to the method described therein by pressing the polymer film onto the device using a silicone stamp heated to a temperature at least 100°C above the glass transition temperature of the material of the device or of the device and the polymer film. This results in the melting of at least one of the two materials to be bonded, so that the polymer film tightly seals the bottom of the cavities of the cell cultivation device after the materials have cooled.

[0011] The present invention is based on the technical problem of providing a method for producing a foil-covered workpiece, in particular a membrane base plate, which is as simple and efficient as possible, which overcomes the problems of the methods in the prior art and in particular makes it possible to produce a foil-covered workpiece, in particular a membrane base plate, which has / which has individual foil surfaces, in particular membrane surfaces, which are connected in a solvent-free and residue-free manner to at least one part of the workpiece to be foil-covered, in particular to the bottom of the cavities of the workpiece, in particular the membrane base plate, and in this case have a particularly high level of flatness or planarity compared to the prior art.

[0012] In the context of the present invention, the term "cavity" refers to a hollow space defined by a wall. In a particularly preferred embodiment of the present invention, a "cavity" is a well of a plate, in particular a multiwell plate.

[0013] In the context of the present invention, the term "film" refers to a single- or multi-layer, thin, flat structure. A "film" can be composed of a single material or multiple materials. According to the invention, a "film" can, for example, comprise materials selected individually, in combination, or as a mixture from: metals, plastics, natural or synthetic polymers, fibers, filaments, polysaccharides, and polypeptides. The term thus encompasses, for example, metal foils, plastic films, in particular polymer films, but also nonwovens composed of one or more materials, in particular fiber nonwovens, such as paper, as well as woven films and nonwovens. The "film" can be transparent, translucent, or opaque.In the context of the present invention, a "film" can be mono- or unidirectionally permeable, in particular omnipermeable, semipermeable, selectively permeable, or even nonpermeable. The "film" can be coated or uncoated. In a particularly preferred embodiment, the "film" is a "membrane."

[0014] In the context of the present invention, the term “membrane” refers to a “film” which has a certain permeability for one or more substances, in particular is at least selectively permeable, i.e. has at least a selective permeability for one or more substances.

[0015] In the context of the present invention, a “film surface” or “membrane surface” is understood to mean a spatially limited portion of a film or membrane.

[0016] In the context of the present invention, an "outer contour" is understood to mean the outline of an object that delimits the object from its surroundings. An "inner contour," on the other hand, is understood to mean the boundary of an object's interior space. Thus, according to the invention, the term "outer contour of an open end of the at least one cavity" refers to the outer contour of the structure forming the open end of the cavity. The term "inner contour of the open end of the at least one cavity" correspondingly describes the inner contour of the open end of the structure forming the cavity.

[0017] The term "punch" refers to a material recess created by applying pressure. Particularly preferably, the at least one "punch" by which the at least one film surface or the at least one membrane surface is defined is created using a punching die with correspondingly shaped cutting edges.

[0018] According to the invention, the term “flatness tolerance” refers to the tolerable range for the deviation of the flatness or planarity of a surface from an ideal flat surface. The tolerance limits are defined by two imaginary planes, each of which is parallel to an ideal flat surface and is spaced apart by a distance corresponding to the value of the “flatness tolerance”. For example, a “flatness tolerance” of 100 pm refers to a maximum distance of 100 pm, measurable over the entire film surface, in particular over the entire membrane surface, between the maximum positive and the maximum negative deviation from the ideal flat surface. The maximum distance of 100 pm can, for example, result from a maximum positive deviation (curvature) of 80 pm (+80 pm) in relation to the ideal flat surface and a maximum negative deviation (depression) of 20 pm (-20 pm) in relation to the ideal flat surface.

[0019] According to the invention, the "averaged flatness tolerance" refers to the arithmetic mean of the individual "flatness tolerances" of the film surfaces, in particular the membrane surfaces, of a film-coated workpiece, in particular a membrane base plate. In contrast to a "flatness tolerance of 100 μm," an "averaged flatness tolerance of 100 μm" allows the distance between the maximum positive and the maximum negative deviation from the ideal flat surface for individual film surfaces, in particular for individual membrane surfaces, of the film-coated workpiece, in particular the membrane base plate, to be greater than 100 μm, provided that the distance averaged across all film surfaces, in particular across all membrane surfaces, of the film-coated workpiece, in particular the membrane base plate, is at most 100 μm.Thus, the distance between the maximum positive and the maximum negative deviation from the ideal flat surface for a single or multiple film surfaces, in particular membrane surfaces, of the film-coated workpiece, in particular the membrane base plate, can be slightly more than 100 pm, for example, provided that the distance between the maximum positive and the maximum negative deviation from the ideal flat surface for other film surfaces, in particular membrane surfaces, of the film-coated workpiece, in particular the membrane base plate, is less than 100 pm and a distance of at most 100 pm results when averaged over all film surfaces, in particular over all membrane surfaces, of the film-coated workpiece, in particular the membrane base plate.

[0020] According to the invention, the measurement of the flatness or planarity of a surface, in particular the maximum positive and the maximum negative deviation from an ideal flat surface, can preferably be measured by means of white light interferometry (WLI), in particular using a chromatic white light sensor.

[0021] In the context of the present invention, the terms "comprising" and "having" are understood to mean that, in addition to the elements explicitly covered by these terms, further, not explicitly mentioned elements can be added. In the context of the present invention, these terms are also understood to mean that only the explicitly mentioned elements are covered and no further elements are present. In this particular embodiment, the meaning of the terms "comprising" and "having" is synonymous with the term "consisting of". Furthermore, the terms "comprising" and "having" also encompass compositions which, in addition to the explicitly mentioned elements, also contain further elements not mentioned, which, however, are of a functionally and qualitatively subordinate nature. In this embodiment, the terms "comprising" and "having" are synonymous with the term "consisting essentially of".

[0022] In the context of the present invention, the term "and / or" means that all members of a group linked by the term "and / or" are disclosed both alternatively to one another and cumulatively among themselves in any combination. For the expression "A, B and / or C," this means that the following disclosure content is to be understood: a) A or B or C or b) (A and B) or c) (A and C) or d) (B and C) or e) (A and B and C).

[0023] The present invention solves the underlying problem through the subject matter of the independent claims. The invention particularly relates to a method for producing a foil-covered workpiece, comprising the steps: a) providing a workpiece made of a first material, b) providing a foil, in particular a membrane, made of a second material, wherein the foil, in particular the membrane, has at least one foil surface, in particular at least one membrane surface, which is delimited by at least one punching, and wherein the at least one foil surface, in particular the at least one membrane surface, is held in the foil, in particular in the membrane, by means of at least one connection, c) contacting the workpiece with the foil, in particular with the membrane, so that the at least one foil surface, in particular the at least one membrane surface, of the foil, in particular the membrane,comes into alignment with a part of the workpiece to be filmed, d) contacting a stamp with the film, in particular with the membrane, so that the at least one film surface, in particular the at least one membrane surface, bonds with the workpiece and seals the part of the workpiece to be filmed, wherein the stamp has a temperature which is above the glass transition temperature of the first and / or second material, and e) removing the heated stamp to obtain a filmed workpiece.

[0024] According to a preferred embodiment of the present invention, the workpiece provided in step a) is a plate, in particular a multiwell plate.

[0025] Particularly preferably, the workpiece provided in step a), in particular the plate, preferably the multiwell plate, comprises at least one cavity with two open ends.

[0026] In a preferred embodiment of the present invention, the film provided in step b) is a membrane. The film provided in step b), in particular the membrane, preferably comprises at least one film surface, in particular at least one membrane surface, which is smaller than or equal to the outer contour of the part of the workpiece to be filmed, in particular the outer contour of an open end of the at least one cavity, and is larger than the inner contour of the part of the workpiece to be filmed, in particular the inner contour of the open end of the at least one cavity, wherein the at least one film surface, in particular the at least one membrane surface, is delimited by at least one punched area.

[0027] According to a particularly preferred embodiment, each of the film surfaces, in particular membrane surfaces, has a separate punch. According to this preferred embodiment of the present invention, the individual film surfaces, in particular membrane surfaces, do not have a common punch. Preferably, the individual film surfaces, in particular membrane surfaces, and the punches in the film, in particular in the membrane, which respectively delimit the individual film surfaces, in particular membrane surfaces, are spaced apart from one another. Particularly preferably, the individual film surfaces, in particular membrane surfaces, and the punches in the film, in particular in the membrane, which respectively delimit the individual film surfaces, in particular membrane surfaces, do not directly adjoin one another.

[0028] In a preferred embodiment of the present invention, the individual film surfaces, in particular membrane surfaces, and the punchings in the film, in particular in the membrane, which respectively delimit the individual film surfaces, in particular membrane surfaces, are spaced apart from one another by at least 0.5 mm, preferably at least 1 mm, preferably at least 1.5 mm, preferably at least 1 mm, preferably at least 1.5 mm, preferably at least 2 mm, preferably at least 2.5 mm, preferably at least 3 mm, preferably at least 3.5 mm, preferably at least 4 mm, preferably at least 4.5 mm, preferably at least 5 mm.

[0029] In a preferred embodiment of the present invention, the distance between the outer contour of the part of the workpiece to be filmed, in particular the outer contour of an open end of the at least one cavity, and the inner contour of the part of the workpiece to be filmed, in particular the inner contour of the open end of the at least one cavity, is at most 20 mm, preferably at most 15 mm, preferably at most 10 mm, preferably at most 9 mm, preferably at most 8 mm, preferably at most 7 mm, preferably at most 6 mm, preferably at most 5 mm, preferably at most 4 mm, preferably at most 3 mm, preferably at most 2 mm, preferably at most 1 mm.

[0030] In a preferred embodiment of the present invention, the distance between the outer contour of the part of the workpiece to be filmed, in particular the outer contour of an open end of the at least one cavity, and the inner contour of the part of the workpiece to be filmed, in particular the inner contour of the open end of the at least one cavity, is at least 0.5 mm, preferably at least 0.75 mm, preferably at least 1 mm, preferably at least 1.5 mm, preferably at least 2 mm, preferably at least 2.5 mm, preferably at least 3 mm, preferably at least 3.5 mm, preferably at least 4 mm, preferably at least 4.5 mm, preferably at least 5 mm.

[0031] In a further preferred embodiment of the present invention, the distance between the outer contour of the part of the workpiece to be filmed, in particular the outer contour of an open end of the at least one cavity, and the inner contour of the part of the workpiece to be filmed, in particular the inner contour of the open end of the at least one cavity, is 0.5 mm to 20 mm, preferably 0.5 mm to 10 mm, preferably 0.75 mm to 5 mm, preferably 0.75 mm to 2.5 mm, preferably 1 mm to 5 mm, preferably 1 mm to 2 mm.

[0032] According to a preferred embodiment, the part of the workpiece to be film-coated is an open end of at least one cavity of the workpiece, in particular an open end of at least one cavity of a plate, preferably a multiwell plate. Preferably, in step c) of the method according to the invention, the open end of the at least one cavity of the workpiece, in particular of the plate, preferably of the multiwell plate, is contacted with the film, in particular with the membrane, such that the at least one film surface, in particular the at least one membrane surface, coincides with the open end of the at least one cavity.

[0033] According to a preferred embodiment of the present invention, it can be provided that in step d) the contacting of the stamp with the film, in particular with the membrane, takes place so that the at least one film surface, in particular the at least one membrane surface, connects to the workpiece, in particular with a plate, preferably with a multiwell plate, and closes an open end of at least one cavity of the workpiece, in particular of the plate, preferably of the multiwell plate, wherein the stamp has a temperature which is above the glass transition temperature of the first and / or second material.

[0034] In a preferred embodiment, in step e) of the method according to the invention, the heated stamp is removed to obtain a foiled workpiece, in particular a membrane base plate.

[0035] According to a particularly preferred embodiment of the present invention, the method for producing a foil-covered workpiece is a method for producing a membrane base plate, comprising the steps: a) providing a workpiece, in particular a plate, preferably a multi-well plate, made of a first material, comprising at least one cavity with two open ends, b) providing a film, in particular a membrane, made of a second material, wherein the film, in particular the membrane, has at least one film surface, in particular at least one membrane surface, which is smaller than or equal to the outer contour of an open end of the at least one cavity and larger than the inner contour of the open end of the at least one cavity, wherein the at least one film surface, in particular the at least one membrane surface, is delimited by at least one punching, and wherein the at least one film surface,in particular the at least one membrane surface is held in the film, in particular in the membrane, by means of at least one connection, c) contacting the open end of the at least one cavity with the film, in particular with the membrane, so that the at least one film surface, in particular the at least one membrane surface, coincides with the open end of the at least one cavity, d) contacting a stamp with the film, in particular with the membrane, so that the at least one film surface, in particular the at least one membrane surface, bonds with the workpiece, in particular with the plate, preferably with the multiwell plate, and closes the open end of the at least one cavity, wherein the stamp has a temperature that is above the glass transition temperature of the first and / or second material, and e) removing the heated stamp to obtain a foil-covered workpiece, in particular a membrane base plate.

[0036] The method according to the present invention advantageously allows for efficient, solvent-free, and residue-free bonding of a part of a workpiece to be laminated, in particular a workpiece comprising at least one cavity, in particular a plate comprising at least one cavity, preferably a multiwell plate, to a film, in particular to a membrane, to obtain a film-coated workpiece, in particular to obtain a membrane base plate. The method is characterized in particular in that the provided film, in particular the provided membrane, has at least one film surface, in particular at least one membrane surface, which is delimited by at least one punched portion.

[0037] In a particularly preferred embodiment of the present invention, in a step a1) carried out before step b), preferably before step a) and step b), a punching of a film, in particular a membrane, takes place to obtain the film, in particular a membrane, provided in step b), that is to say to obtain a film, in particular a membrane, which has at least one film surface, in particular at least one membrane surface, which is delimited by at least one punching, wherein the at least one film surface, in particular the at least one membrane surface, is held by means of at least one connection in the film, in particular in the membrane.

[0038] Preferably, the punching of the film, in particular the membrane, in step a1) takes place in a device according to the invention for producing a film-coated workpiece, in particular in a device according to the invention for producing a membrane base plate.

[0039] Particularly preferably, both the punching of the film, in particular the membrane, according to step a1) and the contacting of a stamp with the film, in particular with the membrane, so that the at least one film surface, in particular the at least one membrane surface, connects to the workpiece and closes the part of the workpiece to be filmed according to step d) are carried out in a device according to the invention for producing a film-coated workpiece, in particular in a device according to the invention for producing a membrane base plate.

[0040] According to a preferred embodiment of the present invention, steps a), b), c), d) and e), preferably steps a1), a), b), c), d), e), e1) and f), particularly preferably all steps, of the method according to the invention for producing a foil-covered workpiece, in particular the method according to the invention for producing a membrane base plate, are carried out in a device according to the invention for producing a foil-covered workpiece, in particular in a device according to the invention for producing a membrane base plate.

[0041] According to the invention, it can also be provided that the film, in particular membrane, provided in step b), which has at least one film surface, in particular at least one membrane surface, which is delimited by at least one punching, is already provided with a punching, in particular that no punching of the film, in particular membrane, takes place in a device according to the invention for producing a foil-covered workpiece, in particular a membrane base plate. According to this embodiment of the present invention, the punching of the film, in particular the membrane, and the bonding of the at least one film surface, in particular the at least one membrane surface, to the part of the workpiece to be foil-covered take place in different devices.

[0042] Preferably, the at least one film surface, in particular the at least one membrane surface, is smaller than or equal to the outer contour of a part of the workpiece to be filmed, in particular the outer contour of an open end of at least one cavity of the workpiece, in particular the plate, preferably the multiwell plate, and larger than the inner contour of the part of the workpiece to be filmed, in particular the inner contour of the open end of the at least one cavity of the workpiece, in particular the plate, preferably the multiwell plate.

[0043] The at least one punching operation is performed such that the at least one film surface, in particular the at least one membrane surface, is held in the film, in particular in the membrane, via at least one connection. The at least one connection is then melted or fused at a temperature that is above the glass transition temperature of the second material of the film, in particular the membrane, and / or above the glass transition temperature of the first material of the workpiece, in particular the plate, preferably the multiwell plate.

[0044] The method according to the invention ensures that when the part of the provided workpiece to be filmed, in particular the open end of the at least one cavity of the provided workpiece, in particular the provided plate, preferably the multiwell plate, is brought into contact with the at least one film surface, in particular with the at least one membrane surface, of the film, in particular the membrane, and the subsequent contact of a heated stamp, a rapid, solvent-free and residue-free thermal bonding of the at least one film surface, in particular the at least one membrane surface, with the part of the workpiece to be filmed, in particular with the open end of the at least one cavity, occurs.

[0045] By providing a film, in particular a membrane, with pre-punched film surfaces, in particular membrane surfaces, that precisely fit the part of the workpiece to be foiled, in particular for the corresponding open ends of the cavities, it is further achieved that each foil-coated part of the workpiece, in particular that each of the cavities of the foil-coated workpiece, in particular the membrane base plate, has a single, delimited film surface, in particular membrane surface. In the case of membrane base plates, for example, cross-contamination between the individual cavities can be excluded in this way. Furthermore, by providing a film, in particular a membrane, with film surfaces delimited by at least one punch, in particular membrane surfaces, which are held in the film, in particular in the membrane, via at least one connection, it is possible to carry out the process quickly, precisely, and cost-effectively.This is particularly true because the film, in particular the membrane, with the pre-punched film surfaces, in particular the pre-punched membrane surfaces, can be used as a roll product. After thermally bonding the film surfaces, in particular the membrane surfaces, to the part of the workpiece to be foiled, in particular to the open ends of the cavities, no further cutting or punching of the film, in particular the membrane, is necessary. This significantly reduces the risk of contamination from punched sections, as well as the risk of leaks forming in the welded edge due to cracks in the film, in particular in the membrane.

[0046] A further advantage of the method according to the invention is that the film surfaces, especially membrane surfaces, that seal the part of the workpiece to be film-coated, in particular the open end of the individual cavities, exhibit particularly high flatness or planarity. Furthermore, the film-coated workpieces obtained with the method according to the invention, in particular the membrane base plates obtained with the method according to the invention, are advantageously characterized by high stability, exhibit high resistance to simple mechanical stress, and are suitable for use over extended periods. In the case of membrane base plates, this is particularly suitable for use over extended cultivation periods.

[0047] In a preferred embodiment of the present invention, the workpiece provided in step a), in particular the plate provided in step a), preferably a multiwell plate, has at least 2, preferably at least 6, preferably at least 12, preferably at least 24, preferably at least 48, preferably at least 96, preferably at least 384, preferably at least 1536, preferably at least 3456, cavities.

[0048] According to a further preferred embodiment of the present invention, the workpiece provided in step a), in particular the plate provided in step a), preferably a multiwell plate, has at most 3456, preferably at most 1536, preferably at most 384, preferably at most 96, preferably at most 48, preferably at most 24, preferably at most 12, preferably at most 6, cavities.

[0049] Particularly preferably, the workpiece provided in step a), in particular the plate provided in step a), preferably a multiwell plate, has 2, preferably 6, preferably 12, preferably 24, preferably 48, preferably 96, preferably 384, preferably 1536, preferably 3456 cavities.

[0050] According to a particularly preferred embodiment of the present invention, the at least one cavity is at least one well.

[0051] According to a preferred embodiment, the film, in particular the membrane, has at most two layers.

[0052] In a preferred embodiment of the present invention, the film, in particular the membrane, is a two-layer film, in particular a two-layer membrane. Particularly preferably, the film, in particular the membrane, is a single-layer film, in particular a single-layer membrane.

[0053] The film, in particular the membrane, preferably consists of a single material. According to the invention, it can also be provided that the film has more than two layers. An outer layer of the film facing the workpiece can be an adhesive layer and / or an adhesion promoter layer. A carrier film can preferably be provided on a side of the film facing away from the workpiece. Further layers of the film can preferably be arranged on the side of the carrier film facing the workpiece. Alternatively or additionally, further layers of the film can be arranged on the side of the carrier film facing away from the workpiece. These layers can be, for example, lacquer layers and / or metal layers, which are each present over the entire surface or partially in the respective layer plane.

[0054] In a further preferred embodiment of the present invention, the film is a membrane, preferably a filter membrane.

[0055] In a preferred embodiment of the present invention, the film, in particular the membrane, preferably the filter membrane, has a thickness of 5 pm to 1000 pm, preferably 50 pm to 800 pm, preferably 100 pm to 600 pm, preferably 250 pm to 400 pm.

[0056] In a further preferred embodiment of the present invention, the film, in particular the membrane, preferably the filter membrane, has a thickness of 5 pm to 60 pm, preferably 10 pm to 50 pm, preferably 15 pm to 45 pm, preferably 20 pm to 40 pm.

[0057] The film, in particular the membrane, preferably the filter membrane, particularly preferably has a thickness of at least 5 pm, preferably at least 10 pm, preferably at least 15 pm, preferably at least 20 pm, preferably at least 25 pm, preferably at least 30 pm, preferably at least 35 pm, preferably at least 40 pm, preferably at least 45 pm, preferably at least 50 pm, preferably at least 75 pm, preferably at least 100 pm, preferably at least 200 pm, preferably at least 250 pm, preferably at least 300 pm, preferably at least 400 pm, preferably at least 500 pm.

[0058] In a preferred embodiment, the film, in particular the membrane, preferably the filter membrane, has a thickness of at most 1000 pm, preferably at most 900 pm, preferably at most 800 pm, preferably at most 700 pm, preferably at most 600 pm, preferably at most 500 pm, preferably at most 400 pm, preferably at most 300 pm, preferably at most 250 pm, preferably at most 200 pm, preferably at most 150 pm, preferably at most 100 pm, preferably at most 90 pm, preferably at most 80 pm, preferably at most

[0059] 70 pm, preferably at most 60 pm, preferably at most 55 pm, preferably at most 50 pm, preferably at most 45 gm, preferably at most 40 gm, preferably at most 35 gm, preferably at most 30 gm.

[0060] In particular, the film, in particular the membrane, preferably the filter membrane, has a thickness of 5 gm to 60 gm, preferably of 10 gm to 50 gm.

[0061] In a particularly preferred embodiment of the present invention, the first material is a plastic. Particularly preferably, the first material is at least one material selected from the group consisting of polyethylene terephthalate (PET), polystyrene (PS), polyvinylidene fluoride (PVDF), and polycarbonate (PC).

[0062] In a preferred embodiment of the present invention, the second material is a plastic. Particularly preferably, the second material is at least one material selected from the group consisting of polyethylene terephthalate (PET), polystyrene (PS), polyvinylidene fluoride (PVDF), and polycarbonate (PC).

[0063] In a preferred embodiment, the first and second materials are the same material.

[0064] According to a particularly preferred embodiment of the present invention, the first and / or second material is polycarbonate (PC).

[0065] Particularly preferably, the first material is PET and the second material is PS. Preferably, the first material is PET and the second material is PVDF. In another preferred embodiment, the first material is PET and the second material is PET. Particularly preferably, the first material is PET and the second material is PC.

[0066] According to a preferred embodiment of the present invention, the first material is PS and the second material is PET. Preferably, the first material is PS and the second material is PS. In another preferred embodiment, the first material is PS and the second material is PVDF. Preferably, the first material is PS and the second material is PC.

[0067] In a preferred embodiment of the present invention, the first material is PVDF and the second material is PET. Preferably, the first material is PVDF and the second material is PS. According to a further embodiment, the first material is PVDF and the second material is PVDF. Preferably, the first material is PVDF and the second material is PC.

[0068] In a further preferred embodiment, the first material is PC and the second material is PET. In a particularly preferred embodiment, the first material is PC and the second material is PS. In a further preferred embodiment, the first material is PC and the second material is PVDF. Particularly preferably, the first material is PC and the second material is PC.

[0069] In a further preferred embodiment of the present invention, the at least one film surface, in particular the at least one membrane surface, is held in the film, in particular in the membrane, by at least two, preferably exactly two, connections. Preferably, the at least one film surface, in particular the at least one membrane surface, is held in the film, in particular in the membrane, by at least three, preferably exactly three, connections. In a further preferred embodiment, the at least one film surface, in particular the at least one membrane surface, is held in the film, in particular in the membrane, by at least four, preferably exactly four, connections. In a particularly preferred embodiment, two connections are opposite one another.

[0070] In a particularly preferred embodiment of the present invention, the at least one connection is at least one web.

[0071] Preferably, the at least one web has a width of at least 0.05 mm, preferably at least 0.1 mm, preferably at least 0.15 mm, preferably at least 0.2 mm, preferably at least 0.25 mm, preferably at least 0.3 mm, preferably at least 0.35 mm, preferably at least 0.4 mm, preferably at least 0.4 mm, preferably at least 0.45 mm, preferably at least 0.5 mm.

[0072] In a further preferred embodiment, the at least one web has a width of at most 2 mm, preferably at most 1.75 mm, preferably at most 1.5 mm, preferably at most 1.25 mm, preferably at most 1 mm, preferably at most 0.75 mm, preferably at most 0.5 mm, preferably at most 0.45 mm, preferably at most 0.4 mm, preferably at most 0.35 mm, preferably at most 0.3 mm, preferably at most 0.25 mm, preferably at most 0.2 mm, preferably at most 0.15 mm, preferably at most 0.1 mm, preferably at most 0.05 mm. Particularly preferably, the at least one web has a width of 0.05 mm to 2 mm, preferably 0.05 mm to 1.5 mm, preferably 0.1 mm to 1 mm, preferably 0.15 mm to 0.75 mm, preferably 0.15 mm to 0.5 mm, preferably 0.15 mm to 0.4 mm, preferably 0.15 mm to 0.3 mm, preferably 0.15 mm to 0.25 mm.

[0073] In a preferred embodiment of the present invention, the at least one web has a length of at least 0.1 mm, preferably at least 0.2 mm, preferably at least 0.3 mm, preferably at least 0.4 mm, preferably at least 0.5 mm, preferably at least 0.6 mm, preferably at least 0.7 mm, preferably at least 0.8 mm, preferably at least 0.9 mm, preferably at least 1 mm, preferably at least 1.25 mm, preferably at least 1.5 mm, preferably at least 1.75 mm, preferably at least 2 mm, preferably at least 2.25 mm, preferably at least 2.5 mm, preferably at least 2.75 mm, preferably at least 3 mm.

[0074] In a further preferred embodiment, the at least one web has a length of at most 5 mm, preferably at most 4 mm, preferably at most 3 mm, preferably at most 2.75 mm, preferably at most 2.5 mm, preferably at most 2.25 mm, preferably at most 2 mm, preferably at most 1.75 mm, preferably at most 1.5 mm, preferably at most 1.25 mm, preferably at most 1 mm, preferably at most 0.75 mm, preferably at most 0.5 mm, preferably at most 0.25 mm, preferably at most 0.1 mm.

[0075] Particularly preferably, the at least one web has a length of 0.1 mm to 5 mm, preferably 0.5 mm to 5 mm, preferably 0.75 mm to 5 mm, preferably 1 mm to 4 mm, preferably 1 mm to 3.5 mm, preferably 1.5 mm to 3 mm, preferably 1.5 mm to 2.75 mm, preferably 1.5 mm to 2.5 mm.

[0076] According to a preferred embodiment of the present invention, the at least one part of the workpiece to be foiled, in particular the at least one cavity, preferably the at least one open end of the at least one cavity, has a round, rectangular, in particular square, or polygonal cross-section.

[0077] In a particularly preferred embodiment of the present invention, the film, in particular the membrane, has a number of film surfaces, in particular membrane surfaces, corresponding to the number of parts of the workpiece to be filmed, in particular the cavities. Particularly preferably, the film surfaces, in particular the membrane surfaces, are each smaller than or equal to the outer contour of the part of the workpiece to be filmed, in particular the outer contour of the open end of the cavities, and larger than the inner contour of the part of the workpiece to be filmed, in particular the inner contour of the open end of the cavities, wherein the film surfaces, in particular the membrane surfaces, are each delimited by a punched area.

[0078] In a preferred embodiment of the present invention, the stamp in step d) has a temperature which is at most 5 °C, preferably at most 10 °C, preferably at most 15 °C, preferably at most 20 °C, preferably at most 25 °C, preferably at most 30 °C, preferably at most 40 °C, preferably at most 50 °C, above the glass transition temperature of the first and / or second material, in particular above the glass transition temperature of the material with the lower glass transition temperature.

[0079] According to a preferred embodiment of the present invention, the stamp in step d) has a temperature which is at least 5 °C, preferably at least 10 °C, preferably at least 15 °C, preferably at least 20 °C, preferably at least 25 °C, preferably at least 30 °C, above the glass transition temperature of the first and / or second material, in particular above the glass transition temperature of the material with the lower glass transition temperature.

[0080] Preferably, the contacting of the stamp with the film, in particular with the membrane, in step d) takes place at a temperature which is at most 5 °C, preferably at most 10 °C, preferably at most 15 °C, preferably at most 20 °C, preferably at most 25 °C, preferably at most 30 °C, preferably at most 40 °C, preferably at most 50 °C, above the glass transition temperature of the first and / or second material, in particular above the glass transition temperature of the material with the lower glass transition temperature.

[0081] Particularly preferably, the contacting of the stamp with the film, in particular with the membrane, in step d) takes place at a temperature which is at least 5 °C, preferably at least 10 °C, preferably at least 15 °C, preferably at least 20 °C, preferably at least 30 °C, above the glass transition temperature of the first and / or second material, in particular above the glass transition temperature of the material with the lower glass transition temperature.

[0082] According to a further preferred embodiment, the contacting of the stamp with the film, in particular with the membrane, in step d) takes place at a temperature of 120 °C to 180 °C, preferably 125 °C to 175 °C, preferably 130 °C to 170 °C, preferably 135 °C to 165 °C, particularly preferably 140 °C to 160 °C.

[0083] In a further preferred embodiment of the present invention, the stamp is contacted with the film, in particular with the membrane, in step d) at a temperature of at least 120 °C, preferably at least 125 °C, preferably at least 130 °C, preferably at least 135 °C, preferably at least 140 °C, preferably at least 145 °C, preferably at least 150 °C, preferably at least 155 °C, preferably at least 160 °C, preferably at least 165 °C, preferably at least 170 °C, preferably at least 175 °C, preferably at least 180 °C.

[0084] In a preferred embodiment of the present invention, the stamp is contacted with the film, in particular with the membrane, in step d) at a temperature of at most 200 °C, preferably at most 195 °C, preferably at most 190 °C, preferably at most 185 °C, preferably at most 180 °C, preferably at most 175 °C, preferably at most 170 °C, preferably at most 165 °C, preferably at most 160 °C.

[0085] Preferably, the stamp is contacted with the film, in particular with the membrane, in step d) for a time of 0.1 to 5 seconds, preferably 0.25 to 4 seconds, preferably 0.5 to 3 seconds, preferably 0.75 to 2.5 seconds, particularly preferably 1 to 2 seconds.

[0086] Particularly preferably, the contact of the stamp with the film, in particular with the membrane, in step d) takes place for a time of at most 5 seconds, preferably at most 4 seconds, preferably at most 3 seconds, particularly preferably at most 2 seconds.

[0087] According to a preferred embodiment of the present invention, the contacting of the stamp with the film, in particular with the membrane, in step d) takes place at a temperature of 120 °C to 180 °C and for a time of at most 4 seconds.

[0088] In a further preferred embodiment of the present invention, the stamp is contacted with the film, in particular with the membrane, in step d) for a time of at least 0.1 seconds, preferably at least 0.25 seconds, preferably at least 0.5 seconds, preferably at least 0.75 seconds, preferably at least 1 second, preferably at least 1.25 seconds, preferably at least 1.5 seconds, preferably at least 1.75 seconds, preferably at least 2 seconds, preferably at least 2.5 seconds, preferably at least 3 seconds.

[0089] In a preferred embodiment, the stamp is brought into contact with the film, in particular with the membrane, in step d) with a force of 0.25 kN to 25 kN, preferably 0.5 kN to 20 kN, preferably 0.75 kN to 15 kN, preferably 1 kN to 10 kN, preferably 1.25 kN to 7.5 kN, preferably 1.5 kN to 5 kN, preferably 1.75 kN to 4.5 kN, preferably 2 kN to 4 kN, particularly preferably 2.5 kN to 3.5 kN.

[0090] According to a further preferred embodiment of the present invention, the stamp is brought into contact with the film, in particular with the membrane, in step d) with a force of at least 0.25 kN, preferably at least 0.5 kN, preferably at least 1 kN, preferably at least 1.5 kN, preferably at least 2 kN, preferably at least 2.5 kN, preferably at least 3 kN, preferably at least 3.5 kN, preferably at least 4 kN, preferably at least 4.5 kN, preferably at least 5 kN, preferably at least 7.5 kN, preferably at least 10 kN, preferably at least 15 kN.

[0091] Preferably, the stamp is brought into contact with the film, in particular with the membrane, in step d) with a force of at most 30 kN, preferably at most 25 kN, preferably at most 20 kN, preferably at most 17.5 kN, preferably at most 15 kN, preferably at most 12.5 kN, preferably at most 10 kN, preferably at most 7.5 kN, preferably at most 5 kN, preferably at most 4 kN, preferably at most 3 kN, preferably at most 2 kN.

[0092] In a further preferred embodiment of the present invention, the stamp is brought into contact with the film, in particular with the membrane, in step d) at a temperature of 140 to 160 °C, preferably 145 to 155 °C, particularly preferably 150 °C, for a time of 0.5 to 2.5 seconds, preferably 1 to 2 seconds, particularly preferably 1.25 to 1.75 seconds, and with a force of 1 to 6 kN, preferably 2 to 5 kN, particularly preferably 3 to 4 kN. In a preferred embodiment, it can be provided that the workpiece, in particular the membrane base plate, is cooled, in particular passively cooled, in a step e1) following step e) for a period of 1 to 8 seconds, preferably 2 to 6 seconds, particularly preferably 3 to 5 seconds.

[0093] Under the aforementioned conditions, a particularly high level of flatness, in particular a particularly low levelness tolerance, of the film surface, in particular the membrane surface, with a thickness of 25 μm, sealing at least one part of the workpiece to be filmed, was observed. The combination of the hot stamping parameters results in the parts of the workpiece to be filmed being sealed efficiently, tightly, and particularly evenly, without excessively high temperatures, excessively long stamping times, and / or excessively high stamping forces leading to damage, in particular deformation, of the workpiece itself to be filmed and / or the film surface, in particular the membrane surface, on the part of the workpiece to be sealed.A person skilled in the art is aware that the choice of hot stamping parameters depends on the material of the workpiece, the material of the film, in particular the membrane, as well as the thickness of the film, in particular the membrane, and that the parameters must therefore be adapted accordingly to the specific application. According to a preferred embodiment of the present invention, the film, in particular the membrane, is an at least partially porous film, in particular an at least partially porous membrane.

[0094] In a preferred embodiment of the present invention, the film, in particular the membrane, has an average pore size of 0.05 pm to 15 pm, preferably 0.1 pm to

[0095] 10 pm, preferably 0.2 pm to 5 pm, preferably 0.3 pm to 4 pm, preferably 0.4 pm to 3 pm, preferably 0.5 pm to 2 pm.

[0096] The film, in particular the membrane, particularly preferably has an average pore size of at least 0.05 pm, preferably at least 0.075 pm, preferably at least 0.1 pm, preferably at least 0.125 pm, preferably at least 0.15 pm, preferably at least 0.175 pm, preferably at least 0.2 pm, preferably at least 0.225 pm, preferably at least 0.25 pm, preferably at least 0.275 pm, preferably at least 0.3 pm, preferably at least 0.325 pm, preferably at least 0.35 pm, preferably at least 0.375 pm, preferably at least 0.4 pm, preferably at least 0.425 pm, preferably at least 0.45 pm, preferably at least 0.475 pm, preferably at least 0.5 pm.

[0097] In a further preferred embodiment of the present invention, the film, in particular the membrane, has an average pore size of at most 15 pm, preferably at most 14 pm, preferably at most 13 pm, preferably at most 12 pm, preferably at most

[0098] 11 pm, preferably at most 10 pm, preferably at most 9 pm, preferably at most 8 pm, preferably at most 7 pm, preferably at most 6 pm, preferably at most 5 pm, preferably at most 4 pm, preferably at most 3 pm, preferably at most 2.5 pm, preferably at most 2 pm, preferably at most 1.5 pm, preferably at most 1 pm, preferably at most 0.75 pm, preferably at most 0.5 pm. In a particularly preferred embodiment of the present invention, the film, in particular the membrane, is a polycarbonate membrane (PC) with an average pore size of 0.05 pm to 10 pm, preferably 0.1 pm to 5 pm, preferably 0.2 pm to 4 pm, preferably 0.25 pm to 3 pm, preferably 0.3 pm to 2 pm, preferably 0.35 pm to 1 pm, preferably 0.4 pm to 0.8 pm.

[0099] Preferably, the film, in particular the membrane, is a polycarbonate membrane (PC) with an average pore size of 0.05 pm to 15 pm, preferably 0.2 pm to 10 pm.

[0100] According to a preferred embodiment of the present invention, the film, in particular the membrane, has a porosity of at least 5%, preferably at least 6%, preferably at least 7%, preferably at least 8%, preferably at least 9%, preferably at least 10%, preferably at least 11%, preferably at least 12%, preferably at least 13%, preferably at least 14%, preferably at least 15%.

[0101] In a further preferred embodiment of the present invention, the film, in particular the membrane, has a porosity of at most 30%, preferably at most 25%, preferably at most 20%, preferably at most 19%, preferably at most 18%, preferably at most 17%, preferably at most 16%, preferably at most 15%, preferably at most 14%, preferably at most 13%, preferably at most 12%, preferably at most 11%, preferably at most 10%.

[0102] Particularly preferably, the film, in particular the membrane, has a porosity of 5 to 30%, preferably 6 to 25%, preferably 7 to 20%, preferably 8 to 18%, preferably 10 to 16%, preferably 12 to 14%.

[0103] According to a preferred embodiment, the film, in particular the membrane, is transparent. Preferably, the film, in particular the membrane, is translucent. According to a further embodiment of the present invention, the film, in particular the membrane, is opaque. The transparency and / or translucency and / or opacity of the film can also be present only in certain surface areas, i.e. partially, while other surface areas of the film have a transparency and / or translucency and / or opacity that differs from this area. According to the invention, it can be provided that the film, in particular the membrane, is impermeable. In a particularly preferred embodiment of the present invention, the film, in particular the membrane, is permeable, in particular mono- or unidirectionally permeable. Preferably, the film, in particular the membrane, is omnipermeable, semi-permeable, or selectively permeable.

[0104] According to a preferred embodiment of the present invention, the film, in particular the membrane, is a filter membrane. Particularly preferably, the film-covered workpiece is a membrane base plate, in particular a filter plate.

[0105] In a preferred embodiment of the present invention, the workpiece, in particular the membrane base plate, is cooled, in particular passively cooled, in a step e1) following step e1). The cooling, in particular the allowing to cool, preferably takes place in step e1) for a duration of at least 2 seconds, preferably at least 3 seconds, preferably at least 4 seconds, preferably at least 5 seconds, preferably at least 6 seconds. According to a preferred embodiment, the cooling, in particular the allowing to cool, takes place in step e1) for a duration of at most 30 seconds, preferably at most 25 seconds, preferably at most 20 seconds, preferably at most 15 seconds, preferably at most 10 seconds.

[0106] In a preferred embodiment of the present invention, following step e) or e1), in a step f) the at least one film surface, in particular membrane surface, connected to the workpiece, in particular to the membrane base plate, and closing the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, is separated from the film, in particular from the membrane.Particularly preferably, the separation of the at least one film surface, in particular membrane surface, which is connected to the workpiece, in particular the plate, and closes the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, from the film, in particular from the membrane, in step f) is carried out by a movement of the workpiece, in particular the membrane base plate, relative to the film, in particular relative to the membrane, that is to say that the workpiece, in particular the membrane base plate, is moved away from the film, in particular from the membrane.Alternatively, it can also be provided according to the invention that the separation of the at least one film surface, in particular membrane surface, which is connected to the workpiece, in particular to the plate, and closes the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, from the film, in particular from the membrane, in step f) takes place by a movement of the film, in particular the membrane, relative to the workpiece, in particular relative to the membrane base plate, that is to say that the film, in particular the membrane, is moved away from the workpiece, in particular from the membrane base plate, preferably is pulled off.

[0107] In a further embodiment of the present invention, the separation of the at least one film surface, in particular membrane surface, which is connected to the workpiece, in particular the plate, and closes the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, from the film, in particular from the membrane, in step f) is carried out by a movement of the workpiece, in particular the membrane base plate, and the film, in particular and the membrane, that is to say that both the workpiece, in particular the membrane base plate, and the film, in particular the membrane, are moved relative to one another, in particular that the workpiece, in particular the membrane base plate, and the film, in particular the membrane, are moved away from one another.

[0108] In a particularly preferred embodiment of the present invention, the separation of the at least one film surface, in particular membrane surface, which is connected to the workpiece, in particular the plate, and closes the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, from the film, in particular from the membrane, is assisted in step f) by a detachment gate. The detachment gate is in particular horizontally and / or vertically movable. The detachment gate is arranged between the workpiece and the stamp during sealing. The detachment gate is in particular arranged directly adjacent to or adjacent to the film web, preferably arranged at a distance of 0 mm to 10 mm from the film web. The detachment gate is particularly preferably used to lift and / or detach the film web from the workpiece in a controlled manner in step f).The release liner is designed to be particularly rigid and made of materials, individually or in combination, or as a hybrid material selected from: metal, plastic, wood materials, fiber materials. The release liner is preferably 0.1 mm to 10 mm thick to achieve the required flexural rigidity, depending on the material or material combination used.

[0109] If the at least one connection by which the at least one film surface, in particular the at least one membrane surface, is held in the film, in particular in the membrane, in particular the at least one web, has not already been melted in step d), the at least one connection, in particular the at least one web, is torn off in step f) as a result of the workpiece, in particular the membrane base plate, with the at least one film surface, in particular membrane surface, connected to the part of the workpiece to be filmed, in particular to the open end of the at least one cavity of the workpiece, in particular the membrane base plate, and the film, in particular the membrane, moving away from one another.

[0110] The present invention also relates to a foil-coated workpiece, in particular a membrane base plate, producible, in particular produced, by the method according to the invention.

[0111] The foil-coated workpieces, in particular membrane base plates, which can be produced, in particular produced, using the method according to the invention are advantageously characterized in particular in that the foil surfaces, in particular the membrane surfaces, of the foil-coated parts of the workpiece, in particular the foil surfaces, in particular membrane surfaces, forming the bottom of the at least one cavity of the workpiece, in particular the membrane base plates, are particularly flat, in particular particularly planar.

[0112] In a preferred embodiment of the present invention, the film surface, in particular the membrane surface, closing the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, has a flatness tolerance of at most 200 pm, preferably at most 190 pm, preferably at most 180 pm, preferably at most 170 pm, preferably at most 160 pm, preferably at most 150 pm, preferably at most 140 pm, preferably at most 130 pm, preferably at most 120 pm, preferably at most 110 pm, preferably at most 100 pm, preferably at most 90 pm, preferably at most 80 pm, preferably at most 70 pm, preferably at most 60 pm, preferably at most 50 pm.Particularly preferably, the film surface, in particular the membrane surface, closing the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, has a flatness tolerance of 5 pm to 200 pm, preferably 10 pm to 190 pm, preferably 15 pm to 180 pm, preferably 20 pm to 170 pm, preferably 25 pm to 160 pm, preferably at most 30 pm to 150 pm, preferably 35 pm to 140 pm, preferably 40 pm to 130 pm, preferably 45 pm to 120 pm, preferably 50 pm to 100 pm, preferably 55 pm to 100 pm, preferably 60 pm to 100 pm.

[0113] In a further preferred embodiment of the present invention, the workpiece, in particular the membrane base plate, has at least two cavities, each of which has an open end closed by a film surface, in particular by a membrane surface, wherein the flatness tolerance for each of the film surfaces, in particular membrane surfaces, closing the at least two cavities is at most 200 pm, preferably at most 190 pm, preferably at most 180 pm, preferably at most 170 pm, preferably at most 160 pm, preferably at most 150 pm, preferably at most 140 pm, preferably at most 130 pm, preferably at most 120 pm, preferably at most 110 pm, preferably at most 100 pm, preferably at most 90 pm, preferably at most 80 pm, preferably at most 70 pm, preferably at most 60 pm, preferably at most 50 pm.

[0114] According to a preferred embodiment of the present invention, the workpiece, in particular the membrane base plate, has at least two cavities, each of which has an open end closed by a film surface, in particular by a membrane surface, wherein the flatness tolerance for each of the film surfaces, in particular membrane surfaces, closing the at least two cavities is in the range from 5 pm to 200 pm, preferably 10 pm to 190 pm, preferably 15 pm to 180 pm, preferably 20 pm to 170 pm, preferably 25 pm to 160 pm, preferably at most 30 pm to 150 pm, preferably 35 pm to 140 pm, preferably 40 pm to 130 pm, preferably 45 pm to 120 pm, preferably 50 pm to 100 pm, preferably 55 pm to 100 pm, preferably 60 pm to 100 pm.

[0115] In a preferred embodiment, it can also be provided that the workpiece, in particular the membrane base plate, has at least two cavities, each of which has an open end closed by a film surface, in particular by a membrane surface, wherein the flatness tolerance averaged from the flatness tolerances of all film surfaces, in particular membrane surfaces, of the workpiece, in particular the membrane base plate, is at most 200 gm, preferably at most 190 gm, preferably at most 180 gm, preferably at most 170 gm, preferably at most 160 gm, preferably at most 150 gm, preferably at most 140 gm, preferably at most 130 gm, preferably at most 120 gm, preferably at most 110 gm, preferably at most 100 gm, preferably at most 90 gm, preferably at most 80 gm, preferably at most 70 gm, preferably at most 60 gm, preferably at most 50 gm.

[0116] Particularly preferably, the workpiece, in particular the membrane base plate, has at least two cavities, each of which has an open end closed by a film surface, in particular a membrane surface, wherein the flatness tolerance averaged from the flatness tolerances of all film surfaces, in particular membrane surfaces, of the workpiece, in particular the membrane base plate, is in the range from 5 gm to 200 gm, preferably 10 gm to 190 gm, preferably 15 gm to 180 gm, preferably 20 gm to 170 gm, preferably 25 gm to 160 gm, preferably at most 30 gm to 150 gm, preferably 35 gm to 140 gm, preferably 40 gm to 130 gm, preferably 45 gm to 120 gm, preferably 50 gm to 100 gm, preferably 55 gm to 100 gm, preferably 60 gm to 100 gm, lies.

[0117] In a further preferred embodiment of the present invention, the film surface, in particular the membrane surface, closing the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity of the workpiece, in particular the membrane base plate, has no overhang. In particular, the workpieces according to the invention, in particular the membrane base plates, are advantageously characterized in that the film surface, in particular the membrane surface, closing the at least one part of the workpiece to be filmed, in particular the open end of the at least one cavity, does not protrude beyond the outer contour of the part to be filmed, in particular not beyond the outer contour of an open end of the at least one cavity.This means that the film, in particular the membrane, has a film surface, in particular a membrane surface, which is smaller than or equal to the outer contour of the at least one part of the workpiece to be filmed, in particular the outer contour of the open end of the cavity to be closed.

[0118] A further aspect of the present invention relates to a system comprising at least one foil-coated workpiece. Particularly preferably, the system is a membrane base plate system comprising a membrane base plate according to the invention, a receiver plate, and a lid. According to a preferred embodiment of the present invention, the system according to the invention is a filter plate system comprising a filter plate, a receiver plate, and a lid.

[0119] In a preferred embodiment of the present invention, the receiver plate has a number of cavities that corresponds to the number of cavities of the membrane base plate according to the invention, preferably the filter plate. The individual cavities of the receiver plate are arranged such that, in the assembled state of the membrane base plate system, preferably the filter plate system, one cavity of the membrane base plate, preferably the filter plate, extends into the cavity of the receiver plate. In particular, it can be provided that the individual cavities of the receiver plate are arranged such that, in the assembled state of the membrane base plate system, preferably the filter plate system, one cavity of the membrane base plate, preferably the filter plate, extends into the cavity of the receiver plate without the membranes of the membrane base plate, preferably the filter plate, touching the bottom of the cavities of the receiver plate.

[0120] According to a preferred embodiment of the present invention, the individual cavities of the receiver plate serve as liquid reservoirs and enable a mass exchange between the membrane base plate and the liquid in the cavities of the receiver plate.

[0121] In a preferred embodiment of the present invention, the individual cavities of the receiver plate serve as liquid reservoirs to receive a filtrate or eluate from the membrane bottom plate, preferably the filter plate.

[0122] In a further preferred embodiment, the receiver plate can have a number of cavities that differs from the number of cavities in the membrane base plate, preferably the filter plate. For example, the receiver plate can have only one cavity, which serves to receive a filtrate or eluate from the membrane base plate, preferably the filter plate.

[0123] According to a preferred embodiment of the present invention, the material of the receiver plate is a plastic. Preferably, the material of the lid is a plastic. Particularly preferably, the material of the receiver plate and / or the lid is at least one material selected from the group consisting of polystyrene (PS), polycarbonate (PC), polypropylene (PP), polyethylene terephthalate (PET), and cycloolefins (COC). The present invention further relates to a device for producing a foil-coated workpiece, in particular a membrane base plate, preferably a device for carrying out the method according to the invention.

[0124] The device according to the invention for producing a foil-wrapped workpiece comprises: i) at least one lower punching tool and at least one upper punching tool, ii) at least one film, iii) at least one punch, iv) at least one holding device for receiving a workpiece to be foil-wrapped, wherein the upper punching tool and the punch are each arranged on a horizontally movable common carrier so as to be movable vertically upwards and downwards, wherein the lower punching tool is movable vertically upwards and downwards, and wherein the holding device is movable vertically upwards and, with a workpiece to be foil-wrapped arranged therein, can be brought into a position above the lower punching tool and below the film and the punch.

[0125] According to a particularly preferred embodiment of the present invention, the following steps are carried out in the device according to the invention for producing a foil-covered workpiece, in particular the device for producing a membrane base plate, particularly preferably in the device for carrying out the method according to the invention. In particular, the method according to the invention, which can be carried out and is preferably carried out in a device according to the invention for producing a foil-covered workpiece, in particular in a device for producing a membrane base plate, comprises the substeps: i. Moving the lower punching tool vertically upwards beneath the foil, in particular beneath the foil of a foil web, ii.Moving the upper punching tool vertically downwards and pressing the upper punching tool against the lower punching tool so that the upper punching tool and the lower punching tool are in a closed state and the film lying between the upper punching tool and the lower punching tool is punched, iii. Moving the lower punching tool vertically downwards and moving the upper punching tool vertically upwards so that the punched film, in particular the punched film of the film web, is released, iv. Moving the punch horizontally into a position above a workpiece arranged in the holding device so that the punched film, in particular the punched film of the film web, is located between the punch and the workpiece, v. Moving the holding device with the workpiece vertically upwards, vi. Moving the punch vertically downwards onto the workpiece arranged in the holding device so that the punched film is sealed onto the workpiece, vii.Moving the holding device vertically downwards and moving the punch vertically upwards, viii. Removing the foil-wrapped workpiece from the holding device.

[0126] Preferably, after step c) and before step d), the workpiece is fed into the holding device at the same position previously occupied by the punching lower tool. The workpiece is fed into the holding device in a vertical position between the punching lower tool and the film, so that the punching lower tool is arranged below the holding device with the workpiece.

[0127] It is preferred if the upper punching tool and the punch can each be moved vertically upwards and downwards, in particular independently of one another, and can be moved horizontally together, in particular can be moved horizontally on a common carrier.

[0128] Particularly preferably, the upper punching tool and the punch are arranged together on the horizontally movable carrier in a fixed position relative to one another.

[0129] The upper punching tool and / or the punch, in particular on the common carrier, are preferably moved vertically and / or horizontally by means of servo motors.

[0130] For independent vertical movement of the upper punching tool and punch, separate servo motors are preferably provided for the upper punching tool and punch.

[0131] For a joint horizontal movement of the upper punching tool and punch, a common servo motor is preferably provided. The horizontal position of the upper punching tool and / or the horizontal position of the punch, in particular the horizontal position of the common support or the horizontal position of the upper punching tool and the horizontal position of the punch on the common support, is preferably controlled with an accuracy of + / - 0.1 mm, more preferably + / - 0.01 mm, and particularly preferably + / - 0.001 mm.

[0132] The device according to the invention therefore enables the punching of a film and the subsequent sealing of the punched film onto a workpiece to be foiled.

[0133] Particularly preferably, the punching of the film between the lower punching tool and the upper punching tool and the sealing of the film onto a workpiece to be foiled arranged in the holding device takes place at the same horizontal position in the device according to the invention.

[0134] In a preferred embodiment of the device according to the invention for producing a foil-covered workpiece, in particular a membrane base plate, the film is in the form of at least one film web. The device according to the invention preferably comprises at least one film web, at least one film unwinder and at least one film rewinder. Particularly preferably, the film unwinder and / or the film rewinder has a dancer system. In a preferred embodiment, the at least one film web is formed between the film unwinder and the film rewinder of the device according to the invention. By means of the film unwinder and the film rewinder, the film, in particular the membrane, can be unwound from a supply roll in a feed direction and, after processing, can be rewound as film residue, in particular membrane residue.For this purpose, the film unwinding and / or the film rewinding preferably have a dancer system with which the tension of the film, in particular the membrane, can be regulated.

[0135] The film, in particular the membrane, is preferably guided between the film unwinding and the film rewinding in the form of a film web over a work area and is preferably transported by a servomotor, in particular by means of a servomotor-driven gripper feed, in order to achieve precise horizontal transport of the film, in particular the membrane. The position of the film, in particular the membrane, during transport of the film, in particular the membrane, is preferably controlled with an accuracy of + / - 0.1 mm, preferably + / - 0.01 mm, particularly preferably + / - 0.001 mm. The gripper feed has at least one gripper, which can be opened and closed in particular pneumatically or by a servomotor. The gripper is preferably shaped such that it grips the edges of the film web and the central area of ​​the film, in particular the membrane, is not damaged.The gripper feed is arranged in particular upstream of the working area and / or downstream of the working area in the course of the film web.

[0136] Particularly preferably, the at least one film web is a membrane web.

[0137] According to a preferred embodiment of the present invention, the device further comprises an electrostatic unit. The electrostatic unit serves to electrostatically discharge the film, in particular the membrane, and removes electrostatic charges on the film, in particular on the membrane, preferably by means of ionization.

[0138] In a particularly preferred embodiment of the present invention, the device according to the invention for producing a film-wrapped workpiece, in particular a membrane base plate, has a release gate. The release gate is preferably horizontally and / or vertically movable. During sealing, the release gate is arranged between the workpiece and the stamp, in particular on the side of the film facing away from the stamp and the side facing the workpiece, i.e., between the workpiece and the film. Particularly preferably, the release gate serves to lift and / or detach the film web from the workpiece in a controlled manner after sealing and during the lowering of the workpiece and the holding device in the vertical direction.

[0139] In a preferred embodiment of the present invention, the stamp is a silicone stamp.

[0140] In a preferred embodiment, the device according to the invention further comprises a counterpressure element. The counterpressure element is preferably arranged below the holding device for receiving a workpiece to be film-wrapped, in particular arranged horizontally and vertically movable below the holding device for receiving a workpiece to be film-wrapped.

[0141] According to the invention, the device comprises a holding device for receiving at least one workpiece, in particular at least one plate. In a preferred embodiment, the holding device comprises a manually operable drawer. Preferably, the workpiece and the holding device can be manually fed into the work area of ​​the device in this way. In a further embodiment of the invention, it can be provided that the holding device is fed into the work area automatically, in particular by means of a robot system or by means of other means.

[0142] According to the invention, the upper punching tool and the punch are each arranged on a horizontally movable common carrier so as to be movable vertically upwards and downwards, in particular independently of one another. Preferably, the upper punching tool and the punch are mounted together above the film, in particular above the membrane, in a fixed position relative to one another such that the upper punching tool and the punch are movable horizontally together and can each be moved vertically separately, i.e. independently of one another. Particularly preferably, the upper punching tool and the punch are arranged together in a horizontally movable carrier so as to be fixed to one another. The vertical and / or horizontal movement of the upper punching tool and / or the punch, in particular on the common carrier, is preferably carried out by means of servo motors.The horizontal position of the upper punching tool and / or the punch, in particular on the common carrier, is preferably controlled with an accuracy of + / - 0.1 mm, preferably + / - 0.01 mm, particularly preferably + / - 0.001 mm.

[0143] It is particularly preferred if at least the lower punching tool and the workpiece are arranged relative to one another in the holding device such that the punching of the film, in particular the membrane, between the upper punching tool and the lower punching tool, as well as the subsequent sealing of the pre-punched film, in particular the pre-punched membrane, onto the workpiece can be carried out with very high positioning accuracy at the same horizontal position in the working area of ​​the device. The upper punching tool, the lower punching tool, the holding device with the workpiece, as well as the punch and the optional counterpressure element, as well as the optional release gate, then preferably each move into this precise horizontal position.This means that the punching of the film, in particular the membrane, and the sealing of the pre-punched film, in particular the pre-punched membrane, particularly preferably take place at the same position, in particular at the same horizontal position, in the working area of ​​the device according to the invention. The film is only fed in before the start of punching and is removed again after the completion of sealing and detachment, preferably by means of a film unwinding and a film rewinding of the device. Between the start of punching and the completion of sealing and detachment, there is preferably no horizontal movement of the film, in particular the membrane, so that a stationary, precisely positioned processing of the film, in particular the membrane, can take place in the working area.

[0144] The present invention is illustrated below with reference to figures and an example.

[0145] This shows

[0146] Figure 1 shows a film (1), in particular a membrane, with 96 film surfaces (10), in particular membrane surfaces, arranged in a 12 x 8 matrix and delimited by punchings (20) (bottom). Furthermore, an enlargement of a single film surface (10), in particular a membrane surface, delimited by punchings (20) is shown, wherein the film surface (10), in particular the membrane surface, is held in the film (1), in particular in the membrane, via four connections (30), in particular four webs (top).

[0147] Figure 2 shows the underside (121) of a workpiece (120), in particular a multiwell plate, comprising a plurality of cavities (110) with open ends (111). The enlarged detail illustrates that the open ends (111) of the individual cavities (110) on the underside (121) of the workpiece (120), in particular the multiwell plate, are each defined by an outer contour (112) and an inner contour (113).

[0148] Figure 3 shows the contacting of a heated stamp (101) with a film (1), in particular a membrane, placed on the open ends (111) of the cavities (110) of a workpiece (120), in particular a multiwell plate, such that the individual film surfaces (10), in particular membrane surfaces, of the film (1), in particular the membrane, bond to the workpiece (120), in particular the multiwell plate, and the open ends (111) of the cavities (110) of the workpiece (120), in particular the multiwell plate, are closed. To fix the workpiece (120), in particular the multiwell plate, during contacting, it is preferably locked in a holding device (130).

[0149] Figure 4 shows a basic position of a device (100) according to the invention in a schematic and simplified representation. In this basic position of the device (100), there is not yet a workpiece (120) in the work area. A lower punching tool (103) is positioned in a lower vertical position. An upper punching tool (102) is arranged horizontally above the lower punching tool (103), with a film (1) in the form of a film web arranged between the upper punching tool (102) and the lower punching tool (103) and preferably tensioned accordingly with a film tensioner. A punch (101) and a counterpressure element (not shown here) are arranged in a rest position. The upper punching tool (102) and the punch (101) are mounted together above the film (1) in a stationary manner relative to one another such that the upper punching tool (102) and the punch (101) can be moved horizontally together and can each be moved vertically separately.In the embodiment shown here, the upper punching tool (102) and the punch (101) are arranged together on a horizontally movable carrier (140) in a fixed position relative to one another.

[0150] Figure 5 shows the device (100) during the punching of the film (1). To punch the film (1), the lower punching tool (103) is now moved vertically upwards in the working area toward the film (1) and the upper punching tool (102). The upper punching tool (102) is then lowered vertically onto the film (1) and the lower punching tool (103), thereby punching the film (1). In particular, several cuts are made in the film (1).

[0151] Figure 6 shows the device (100) in a standby position prior to sealing a film (1) onto a workpiece (120). After punching (see Figure 5) the film (1), the lower punching tool (103) moves vertically downwards again and the upper punching tool (102) moves vertically upwards. In the embodiment shown here, the carrier (140) with the upper punching tool (102) and the punch (101) is moved horizontally so that the upper punching tool (102) is moved out of the working area and, at the same time, the punch (101) is moved into the working area so that the punch (101) is in the same horizontal position in which the upper punching tool (102) was previously arranged. The film (1) is not moved during this process. For sealing, a workpiece (120) is now brought into a horizontal position above the punching lower tool (103) in a holding device (130).A release gate (105) then moves horizontally beneath the film (1) and thus between the stretched film (1) and the workpiece (120). The release gate (105) has recesses through which the workpiece (120) and / or the stamp (101) can grip during sealing.

[0152] Figure 7 shows the device (100) during the sealing of a workpiece (120) with a film (1). First, the holding device (130) with the workpiece (120) is lifted. The lifting of the workpiece (120) can take place in several steps or stages in order to provide the counterpressure for the punch (101) as a mechanical counter-bearing during sealing. The punch (101) then moves vertically down onto the film (1) and seals the already punched-out film (1) onto the workpiece (120) using thermal energy and mechanical pressure. For this purpose, the punch (101) is preferably shaped such that the number of convex projections on the punch (101) corresponding to the number of cavities (110) of the membrane base plate or the workpiece (120) acts as a stamping surface.the workpiece (120) is applied in a targeted manner in the area of ​​the cavities (110) and not over the entire surface of the membrane base plate or the entire workpiece (120) and / or the detachment gate (105), and can thus apply the energy in a targeted manner. In this way, damage to the membrane base plate or the workpiece (120) and / or the membrane film (1), in particular deformation, can be avoided.

[0153] Figure 8 shows the device (100) after sealing a workpiece (120) with a film (1). After sealing, the punch (101) is moved vertically upwards and moved into a rest position separately or within the common carrier (140) with the upper punching tool (102). The holding device (130) with the workpiece (120) is then lowered again. By lowering the workpiece (120), the release link (105) arranged directly beneath the film (1) releases the film web of the film (1) from the workpiece (120), so that the film surfaces (10) sealed to the workpiece (120) are also released from the film (1).

[0154] Figure 9 shows a top view of the punching lower tool (103), with the hatched areas representing punching openings (103a) into which the punching blades (102a) of the punching upper tool (102) engage during punching. The punching lower tool (103) preferably has a movable release pin (103b) which, in the rest position, is extended and protrudes with its upper side from the surface of the punching lower tool (103). The upper punching tool (102) presses the release pin (103b) into the punching lower tool (103) during punching, so that the release pin (103b) is then approximately flush with the surface of the punching lower tool (103). After punching has been completed, the release pin (103b) moves out of the lower punching tool (103) in the direction of the upper punching tool (102), in particular by means of spring force, in order to mechanically assist the detachment of the film (1) from the lower punching tool.

[0155] Figure 10 shows the upper punching tool (102) with the punching blades (102a), which are preferably arranged to be movable so as to be recessed into the surface of the upper punching tool (102). In the rest position, the punching blades (102a) are arranged in a recessed position in the upper punching tool (102) in order to be protected from damage and / or contamination. The upper punching tool (102) also has an air opening (102b) to prevent air pockets between the film (1) and the surface of the upper punching tool (102) when the tools are moved together, so that the film (1) can lie flat between the two tools. The punching openings (103a) in the lower punching tool (103) also prevent corresponding air pockets there. When the upper punching tool (102) is brought together with the lower punching tool (103), the punching knives (102a) are then extended accordingly in order to cut the film (1) between the two tools.Figure 10 shows four punching blades that cut or punch the film (1) in such a way that loose film sections are avoided as waste. The punched film sections remain connected to the remaining film.

[0156] Figure 11 a combination of the punching lower tool (103) with the punching upper tool

[0157] (102), wherein it can be seen that the punching blades (102a) of the upper punching tool (102) engage precisely in the correspondingly shaped punching openings (103a) of the lower punching tool (103). The punching openings (103a) are shown in dashed lines, while the punching blades (102a) are shown with a continuous thick line. It can be seen that the punching blades (103a) only engage on three of the four sides of a punched section, and a fourth side is not punched.

[0158] Figure 12 shows the punching process, similar to the enlarged view in Figure 1, with the punched film section (10a) highlighted by hatching. Solid lines show the cuts in the film (1) along which the punched film section (10a) is separated from the film (1). A dashed line shows a fold line (22) where the punched film section (10a) is still connected to the film (1), thus avoiding loose film sections as waste.

[0159] Figures 13a-d show the results of flatness measurements of film bottoms of a membrane bottom plate produced by the method according to the invention.

[0160] The individual working steps of the method carried out with a device according to the invention are explained in detail below and with reference to the figures.

[0161] In a basic position of the device (100) (Figure 4), no workpiece is yet in the work area, with required workpieces preferably being arranged in a storage area. The lower punching tool (103) of the device (100) is positioned in a lower vertical position. The upper punching tool (102) is horizontally above the lower punching tool.

[0162] (103), wherein the film (1), in particular a membrane, is arranged in the form of a film web between the upper punching tool (102) and the lower punching tool (103) and is tensioned accordingly. The punch (101) and the counterpressure element (104) are arranged in a rest position.

[0163] Preferably, the upper punching tool (102) and the punch (101) are arranged together on a horizontally movable support (140) in a fixed position relative to one another, so that when the upper punching tool (102) is arranged in the working area above the lower punching tool (103), the punch (101) is correspondingly positioned outside the working area in the rest position. With a horizontal movement of the support (140), the upper punching tool (102) can then be moved out of the working area, and thus the punch (101) can be moved into the working area, in particular horizontally over a workpiece.

[0164] To punch the film (1), in particular the membrane, the lower punching tool (103) is now moved vertically upwards in the working area towards the film (1), in particular the membrane, and the upper punching tool (102) (see Figure 5). The lower punching tool (103) preferably has positioning aids for the upper punching tool (102), which are in particular designed as depressions. The upper punching tool (102) is now lowered vertically onto the film (1), in particular the membrane, and the lower punching tool (103) so that the upper punching tool (102) and lower punching tool (103) are closed and the film (1), in particular the membrane, is punched. In particular, a plurality of cuts are made in the film (1), in particular in the membrane.The upper punching tool (102) preferably has positioning aids, which are designed in particular as cylindrical or conical pins or studs and can engage in the recesses of the lower punching tool (103). The upper punching tool (102) preferably has roller guides as positioning aids. Roller guides are cylindrical pins which have a plurality of movable roller bearings on their circumference, which hold the pin securely and precisely in the recess of the lower punching tool (103). The web width of the film (1), in particular membrane, is preferably dimensioned such that the positioning aids are arranged outside the area in the working area occupied by the film, in particular membrane.

[0165] After punching, the lower punching tool (103) preferably moves vertically downwards again and the upper punching tool (103) preferably moves vertically upwards. The upper punching tool (102) preferably moves horizontally out of the work area. Particularly preferably, the carrier (140) with the upper punching tool (102) and the punch (101) is moved horizontally so that the upper punching tool (102) moves out of the work area and at the same time the punch (101) is moved into the work area, preferably to the same horizontal position in the work area at which the upper punching tool (102) was previously arranged. The film (1), in particular the membrane, is not moved during this process.

[0166] For sealing, a workpiece (120) is then placed in a holding device (130) and fed into the working area of ​​the device (100) according to the invention, in particular into a horizontal position above the lower punching tool (103) (see Figure 6). In a preferred embodiment, the workpiece (120) is fed into the holding device (130) by means of a manually operated drawer. The holding device (130) is positioned in the working area such that the workpiece (120) is in the same horizontal position as the lowered punching tool (103) arranged below it. The film (1), in particular the membrane, is not moved during this process. A release link (105) then preferably moves horizontally beneath the film (1), in particular beneath the membrane, and thus between the tensioned film (1), in particular the tensioned membrane, and the workpiece (120).For this purpose, the release link (105) preferably has recesses through which the workpiece (120) and / or the stamp (101) can grip during sealing.

[0167] The punch (101) now moves vertically onto the film (1), in particular onto the membrane, while the holding device (130) with the workpiece (120) is lifted (see Figure 7). The lifting of the workpiece (120) can take place in several steps or in several stages in order to provide the counterpressure during sealing for the punch (101) as a mechanical counterbearing. After the workpiece (120) has been lifted in the holding device (130), additional force support of the workpiece (120) in the holding device preferably takes place by inserting a wedge under the holding device (130). The additional insertion of the wedge prevents damage to the punching lower tool (103).The stamp (101) then moves vertically down onto the film (1), in particular onto the membrane, and seals the already pre-punched film (1), in particular the pre-punched membrane, onto the workpiece (120) using thermal energy and mechanical pressure, so that the parts of the workpiece (120) to be laminated are each sealed with a film surface (10), in particular a membrane surface. For this purpose, the stamp (101) is preferably shaped such that a number of convex projections corresponding to the number of cavities (110) of the membrane base plate or the workpiece (120) are present on the stamp (101) as a stamping surface.As a result, the thermal energy and mechanical pressure exerted by the punch (101) on the membrane base plate or the workpiece (120) acts specifically in the area of ​​the cavities (110) and not over the entire surface of the membrane base plate or the entire workpiece (120) and / or the release gate (105), thus allowing the energy to be introduced in a targeted manner. In this way, damage to the membrane base plate or the workpiece (120) and / or the membrane film (1), in particular deformation, can be avoided.

[0168] After sealing, the punch (101) is moved vertically upwards again and moved into a rest position separately or within the common carrier (140) with the upper punching tool (102). The holding device (130) with the workpiece (120) is then lowered again (see Figure 8). By lowering the workpiece (120) arranged in the holding device (130), the release link (105) arranged directly beneath the film (1), in particular the membrane, releases the film web of the film (1), in particular the membrane, from the workpiece (120). The film-wrapped workpiece (120) can then be removed from the work area, in particular by means of the optional drawer.The film (1), in particular the membrane, is then moved horizontally in the feed direction at least so far, in particular by at least the width of a punching and sealing area on the workpiece (120), that a still unpunched area of ​​the film (1), in particular the membrane, is available in the working area and can be punched with the device (100) and sealed onto another workpiece (120) in the next cycle.

[0169] In a particularly preferred embodiment of the present invention, the workpiece is a multi-well plate, preferably a membrane base plate, in particular a filter plate. Membrane base plates are characterized in that they comprise a plurality of cavities, the base of which is each formed by a barrier layer, which is in particular a membrane. The individual cavities of a plate initially have two open ends, with at least one of the open ends having an inner contour and an outer contour. During the production of a membrane base plate, one of the open ends, in particular the end having an inner contour and an outer contour, is closed with a film, in particular with a membrane.Particularly preferably, the film, in particular the membrane, has at least one film surface, in particular at least one membrane surface, which is smaller than or equal to the outer contour of an open end of the at least one cavity and larger than the inner contour of the open end of the at least one cavity, wherein the at least one film surface, in particular the at least one membrane surface, is delimited by at least one punching and wherein the at least one film surface, in particular the at least one membrane surface, is held in the film, in particular in the membrane, by means of at least one connection, in particular after the punching and before the end of the sealing of the membrane surface to the open end of the cavity. In a preferred embodiment of the present invention, the at least one cavity has the shape of a cup.Preferably, the cup is formed as a concave depression when viewed from a first surface of the membrane base plate and is formed as a convex depression when viewed from a second surface (121) of the membrane base plate, which is opposite the first surface of the membrane base plate. The membrane is preferably sealed from the second surface (121) of the membrane base plate onto the open outer convex end of the at least one cavity.

[0170] According to this preferred embodiment, the holding device (130) of the device (100) according to the invention is shaped accordingly to receive the membrane base plate in such a way that the at least one cavity faces the punch (101) with the open end to be sealed, in particular with its convex end and thus with its second surface, and faces the counterpressure element (104) with its first surface.

[0171] According to this embodiment, the optionally present release gate (105) of the device (100) is shaped such that it has at least one recess which passes through the at least one cavity (110) such that the at least one outer, open end of the at least one cavity (110) is aligned with the surface of the release gate (105) facing the stamp (101) or slightly protrudes or is arranged slightly below the surface of the release gate (105), so that the stamp (101) can seal the film (1), in particular the membrane, onto the at least one cavity (110) of the membrane base plate within the recess of the release gate (105).

[0172] The membrane base plate preferably has a plurality of cavities, in particular at least 2, preferably at least 6, preferably at least 12, preferably at least 24, preferably at least 48, preferably at least 96, preferably at least 384, preferably at least 1536, preferably at least 3456 cavities.

[0173] For this purpose, the punch is preferably shaped such that the punch has a number of convex projections corresponding to the number of cavities in the membrane base plate or the workpiece, forming the punching surface. As a result, the thermal energy and mechanical pressure exerted by the punch on the membrane base plate or the workpiece acts specifically in the area of ​​the cavities and not across the entire surface of the membrane base plate or the entire workpiece and / or the release gate, thus allowing the energy to be applied in a targeted manner. In this way, damage to the membrane base plate or the workpiece and / or the membrane film, in particular deformation, can be avoided.

[0174] Particularly preferably, the stamp has a stamping surface corresponding to the part of the workpiece to be film-coated, in particular the membrane base plate. The stamp can also have a differently shaped stamping surface for workpieces to be film-coated that have a different shape than the membrane base plate. In particular, the stamping surface can be designed to cover the entire surface for other workpieces to be film-coated, so that the stamping surface does not need to be adapted to the film surfaces, in particular membrane surfaces, and / or to the at least one part of the workpiece to be film-coated.For other workpieces to be foiled, the stamping surface can also have one or more projections as a stamping surface, which partially correspond to the film surfaces, in particular the membrane surfaces, and / or the at least one part of the workpiece to be foiled, and at the same time the stamping surface can have other areas as a stamping surface that do not correspond to the film surfaces, in particular the membrane surfaces, and / or the at least one part of the workpiece to be foiled.

[0175] The embodiments mentioned in connection with the method according to the invention for producing a foil-coated workpiece, in particular a membrane base plate, also apply mutatis mutandis to the foil-coated workpiece according to the invention, in particular to the membrane base plate, to the system according to the invention, in particular to the membrane base plate system, and to the device according to the invention, and vice versa.

[0176] Further preferred embodiments of the present invention are the subject of the subclaims.

[0177] Examples:

[0178] Example 1: Method for producing a filter base plate

[0179] Step 1 : Pre-cutting of 96 membrane surfaces in a translucent polycarbonate (PC)

[0180] Membrane with a thickness of 25 pm, an average pore size of 0.4 pm, and a porosity of 12.6%. Step 2: Position a 96-well open-ended multiwell plate (material:

[0181] Polycarbonate, glass transition temperature 140°C) under the pre-punched membrane so that the 96 pre-punched membrane surfaces coincide with the open ends of the wells.

[0182] Step 3: Connect the pre-cut membrane surfaces to the open ends of the 96 wells of the plate by hot stamping. Sealing is achieved using a silicone stamp that replicates the contour of the wells. The stamp temperature is 150 °C ± 5 °C. The sealing force with which the stamp is pressed onto the plate is 3.2 kN. The stamp is pressed for 1.6 seconds.

[0183] Step 4: After sealing, the plate is passively cooled in the ambient air for 4 seconds before it is separated from the membrane and can be removed.

[0184] Example 2: Flatness measurement

[0185] The filter plate with 96 wells or cavities produced using the inventive method according to Example 1 was subjected to a flatness measurement. For this purpose, individual wells of the plate sealed with a film were examined for the flatness of the film bottom using a MicroProf 100 white light interferometer (FRT Metrology). The flatness measurement was performed manually using the Aquire program, with the film bottoms of four representative wells or cavities (A2 (Figure 13a), E6 (Figure 13b), H1 (Figure 13c), and H12 (Figure 13d)) being measured from four different directions (horizontal (H), vertical (V), and diagonal (D1, D2)).

[0186] The measurement showed an excellent high flatness or a low flatness tolerance of all measured film bases (Figures 13a-d).

[0187] List of reference symbols:

[0188] Slide 1

[0189] Foil area 10 punched foil area 10a

[0190] Punching 20

[0191] Punching sections 21

[0192] Fold line 22 Connection 30

[0193] Device 100

[0194] Stamp 101

[0195] Punching upper tool 102 Punching knife 102a

[0196] Air opening 102b

[0197] Punching lower tool 103

[0198] Punching openings 103 a

[0199] Release pin 103b Counterpressure element 104

[0200] Transfer scenery 105

[0201] Cavity 110 open end of cavity 111

[0202] Outer contour of the cavity 112 Inner contour of the cavity 113

[0203] Workpiece 120

[0204] Holding device 130

[0205] Carrier 140

Claims

CLAIMS 1. A method for producing a foil-covered workpiece, comprising the steps: a) providing a workpiece (120) made of a first material, b) providing a foil (1) made of a second material, wherein the foil (1) has at least one foil surface (10) defined by at least one punch (20), and wherein the at least one foil surface (10) is held in the foil (1) by means of at least one connection (30), c) contacting the workpiece (120) with the foil (1) such that the at least one foil surface (10) of the foil (1) coincides with a part of the workpiece to be foil-covered, d) contacting a stamp (101) with the foil (1) such that the at least one foil surface (10) bonds with the workpiece (120) and seals the part of the workpiece to be foil-covered, wherein the stamp (101) has a temperature that is above the glass transition temperature of the first and / or second material,and e) removing the heated stamp (101) to obtain a foiled workpiece., 2. Method according to claim 1, characterized in that the workpiece (120) provided in step a) is a plate, in particular a multiwell plate.

3. Method according to claim 1 or 2, characterized in that the film (1) has a thickness of 10 pm to 50 pm.

4. Method according to one of the preceding claims, characterized in that the at least one film surface (10) is held in the film (1) by at least two connections (30).

5. Method according to one of the preceding claims, characterized in that before step b), preferably before step a) and step b), in a step a1) a film is punched to obtain the film (1) provided in step b).

6. Method according to claim 5, characterized in that the method is carried out in a device for producing a foil-coated workpiece according to claims 14 or 15.

7. The method according to claim 6, comprising the sub-steps: i. moving the lower punching tool (103) vertically upwards under the film (1), ii. moving the upper punching tool (102) vertically downwards and pressing the upper punching tool (102) against the lower punching tool (103) so that the upper punching tool (102) and the lower punching tool (103) are in a closed state and the film (1) lying between the upper punching tool (102) and the lower punching tool (103) is punched, iii. moving the lower punching tool (103) vertically downwards and moving the upper punching tool (102) vertically upwards so that the punched film (1) is released, iv. Moving the punch (101) horizontally into a position above a workpiece (120) arranged in the holding device (130) so that the punched film (1) is located between the punch (101) and the workpiece (120), v. Moving the holding device (130) with the workpiece (120) vertically upwards, vi.Moving the punch (101) vertically downwards onto the workpiece (120) arranged in the holding device (130) so that the punched film (1) is sealed onto the workpiece (120), vii. Moving the holding device (130) vertically downwards and moving the punch (101) vertically upwards, viii. Removing the film-wrapped workpiece from the holding device (130).

8. Method according to one of the preceding claims, characterized in that the part of the workpiece to be foiled is an open end (111) of at least one cavity (110) of the workpiece (120).

9. Method according to one of the preceding claims, characterized in that the film (1) has a number of film surfaces (10) corresponding to the number of parts of the workpiece to be filmed, in particular the number of cavities of the workpiece, which are each smaller than or equal to an outer contour (112) of the part of the workpiece to be filmed, in particular as an outer contour (112) of an open end of the cavities, and are larger than an inner contour (113) of the part of the workpiece to be filmed, in particular as an inner contour (113) of an open end of the cavities, wherein the film surfaces (10) are each delimited by a punching (20).

10. Method according to one of the preceding claims, characterized in that the stamp (101) when contacting the film (1) in step d) has a temperature which is at most 5 °C, preferably at most 10 °C, above the glass transition temperature of the first and / or second material.

11. Method according to one of the preceding claims, characterized in that the contacting of the stamp (101) with the film (1) in step d) takes place at a temperature of 120 to 180 °C and for a time of at most 4 seconds.

12. Method according to one of the preceding claims, characterized in that in an additional step f) a separation of the at least one film surface (10) connected to the workpiece (120) and closing the at least one part of the workpiece to be filmed is carried out from the film (1), wherein the separation takes place by a movement of the workpiece (120) relative to the film (1).

13. Method according to one of the preceding claims, characterized in that the film (1) is a polycarbonate membrane (PC) with an average pore size of 0.05 pm to 15 pm, preferably 0.2 pm to 10 pm.

14. Device (100) for producing a foil-coated workpiece, comprising: i) at least one lower punching tool (103) and at least one upper punching tool (102), ii) at least one foil (1), iii) at least one punch (101), iv) at least one holding device (130) for receiving a workpiece (120) to be foil-coated, wherein the upper punching tool (102) and the punch (101) are each arranged on a horizontally movable common support (140) so as to be vertically movable upwards and downwards, wherein the lower punching tool (103) is movable vertically upwards and downwards, and wherein the holding device (130) is movable vertically upwards and, with a workpiece (120) to be film-wrapped arranged therein, can be brought into a position above the lower punching tool (103) and below the film (1) and the punch (101).

15. Device (100) according to claim 14, wherein punching of the film between the lower punching tool (103) and the upper punching tool (102) and sealing of the film onto a workpiece (120) to be foiled arranged in the holding device (130) takes place at the same horizontal position in the device (100).

16. Foil-coated workpiece (120) producible by a method according to one of claims 1 to 13.

17. Foil-wrapped workpiece (120) according to claim 16, wherein the foil-wrapped workpiece is a membrane base plate.

18. Foil-coated workpiece (120) according to claim 17, characterized in that the membrane base plate has at least one cavity (110), of which an open end (111) is closed with a foil surface (10), wherein the foil surface (10) closing the open end (111) of the at least one cavity (110) of the membrane base plate has a flatness tolerance of at most 200 pm, preferably at most 150 pm.

19. Foil-coated workpiece (120) according to claim 17 or 18, characterized in that the membrane base plate has at least two cavities (110), of which in each case one open end (111) is closed with a foil surface (10), wherein the flatness tolerance averaged from the flatness tolerances of all foil surfaces (10) of the membrane base plate is at most 200 pm, preferably at most 150 pm.

20. Membrane base plate system comprising a foiled workpiece (120) according to one of claims 17 to 19, a receiver plate and a cover.

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