WO2023046908A1 - Device having a layer comprising pores with a microstructured functional surface - Google Patents

Abstract

The invention relates to a device having a filter layer comprising pores with a microstructured functional surface. The invention also relates to a system comprising the device. The invention further relates to a method for producing the device, wherein the filter layer is processed by laser ablation and/or an additive method.

Description

Device with a porous layer with a microstructured functional surface

The invention relates to a device with a porous layer with a microstructural functional surface, a system with the device and a method for producing the device.

In biological research, diagnostics or medicine, it is often necessary to process and precisely separate samples or mixtures of substances. In addition to using centrifugal force, mixtures of substances can be processed using gauze, paper filters or sieve fabric and gravity. In addition, individual substances or groups of substances can be separated or washed from a sample mixture by utilizing diffusion effects, as in the case of use in dialysis (artificial blood washing as a blood purification process). Furthermore, membranes are used, for example, with the aim of supplying biological systems with nutrients, removing metabolic products and/or using them as a culture matrix for biological films.

Filter systems used for processing simple as well as complex heterogeneous mixtures, such as blood, have been known for a long time. The use of dialysis, in which a mass transfer is carried out via a semi-permeable membrane with the aid of diffusion effects, is primarily used to separate dissolved molecules from highly concentrated liquids such as blood or plasma. In addition to the dissolved substances, undissolved substances can also be present in liquids, such as cells or suspended matter such as microplastics. Gauze and later sieve fabric were originally used to separate and/or enrich suspensions, for example to enrich isolated cells, cell clusters, tissue, spheroids or particles as well as suspended matter. Since gauze does not have a defined separation limit and partially absorbs the liquid in the sample, which can be disadvantageous in the case of samples with a small volume, filters have been developed for this purpose which have a sieve fabric for filtering and separating mixtures of substances. The openings of screen fabrics are called meshes. Depending on the material used, the filters, which are also called cell strainers depending on the application, are available with different meshes between 1 and 1,000 μm. Especially in the lower range of mesh sizes between 1 and 30 μm, screen fabrics have disadvantages due to their construction. However, in this area there are many of the components of interest for research, especially when studying blood (blood products and blood samples) when the focus is on specific cell populations.

In addition to the lack of precision, the open filter area (porosity) of screen fabrics is very small. In this sense, the porosity describes the sum of all meshes of a filter surface in relation to the entire surface of the filter material. In addition to sieve fabrics, there are filters made of metal materials that cannot be used for cell filtration due to their poor porosity.

US 2010/0 151 190 A1 discloses a membrane with holes to be used in breathable clothing and/or protective cloaks. It is particularly about protection against chemical, radioactive and biological warfare agents. From this point of view, the membrane should be used for filtering, but explicitly more like a gas mask, whereby breathable air should be let through and harmful substances should be kept out. The membrane of the D1 can consist of a polymeric material. The pores have a round shape. The membrane may have dielectric layers arranged in a specific pattern. The membranes are always present at least as a pair. In this sense, the application of current to the dielectric layers serves to control the position of the membranes relative to one another and thus the filter properties.

A filter made of a Meta II material is disclosed in CN 111432910A. It describes a metal plate with holes that is used as a gas filter to filter out particles from the discharge chamber of a laser. The lack of precision as well as the small open filter area of screen fabrics are caused by the production of screen fabrics from plastic threads. The synthetic threads are woven in special patterns. At the same time, the thickness of the individual threads is many times greater in relation to the actual pore. In order to produce precise pores in the micrometer range, a special weaving technique already mentioned is required. At the same time, the threads are several times larger in relation to the resulting pore. Finally, a sieve fabric has an open filter area of 1 to 2% in areas below 10pm. The main part of the fabric is therefore completely unsuitable for filtration. The availability of the screen mesh is also limited to a few manufacturers in view of the manufacturing complexity. Another disadvantageous aspect is the height of the screen mesh.

Due to the design (thread thickness and distances), the screen fabric not only has a standard deviation around the specified mesh size, but there are also significant deviations in the contact points of the individual screen fabric threads. The distances between the screen fabrics in the side view (cross-section) are not equal to the mesh size in the top view at the points of support. The mesh size is determined by measuring air resistance and thus defines the relevant permeability value. When determining the retention limit, the actual mesh size can be determined using monodisperse polymer particles. This defines the actual separation limit (cut-off). However, this deviates from the specified mesh size in the top view. A filter with a screen fabric that has a nominal mesh size of 1 pm in the air resistance measurement has an actual cut-off limit of 10 pm in this application.

The thicker or higher the sieve fabric, the smaller the required mesh size and the smaller the available open filter area, the greater the pressure required to get sample material through the mesh. Pressure means that additional energy must be added beyond gravity to allow separation across the screen mesh. Additional energy can be obtained by centrifugation or added by over or under pressure. However, additional energy when separating cells is disadvantageous in this sense, since animal cells do not have a cell wall and are accordingly elastic and can pass through the mesh sizes during centrifugation. At the same time, the forces have a cell-damaging effect and sometimes lead to apoptosis, which in turn is disadvantageous for downstream processes. For example, apoptotic CD14+ cells (monocytes) cannot be differentiated into macrophages or antigen-presenting cells. Since the cells are too stressed by the isolation, they can no longer be cultivated and are therefore unusable for the production of personalized medicine.

As an alternative to screen mesh, systems with pore openings below 10 pm can be manufactured using plasma bombardment. However, membranes that are perforated by means of plasma bombardment have the decisive disadvantage that the distribution of the pores on the membrane surface is not defined and occurs randomly. Due to the undefined distribution of the pores per area, the plasma bombardment can lead to pores overlapping and thus openings that do not correspond to the defined pore opening. In order to prevent overlapping, only a certain number of pores can be produced per area. The open filter area is thus limited.

The object is to provide a device that enables effective separation processes and is easy to provide.

This object is achieved by a device according to claim 1, a system according to claim 13 and by a method according to claim 15. Further advantageous embodiments and refinements of the invention result from the dependent claims, the figures and the exemplary embodiments. The embodiments of the invention can be combined with one another in an advantageous manner.

A first aspect of the invention relates to a device for filtering a fluid material, comprising a filter layer having at least one polymeric material and having at least one porous and microstructured surface for filtering a fluid material, the pores with a defined shape, which are specifically distributed in the material of the filter layer, so that the filter layer has perforated and non-perforated areas.

The filter layer of the device according to the invention (also referred to as carrier matrix or carrier layer) has openings on the surface through which, in relation to the pore opening to the open filter area, a far higher efficiency can be achieved than with conventional screen fabrics and plasma membranes. The targeted distribution of the pores advantageously enables a classification of perforated to non-perforated areas in defined ratios. The shape of the pores does not have to be exclusively round or square.

In addition to the pore shape and pore distribution, another aspect of the filter layer is advantageous. The layer thickness can be freely selected depending on the desired practical application. Thin, flat materials are particularly advantageous, so that the filter layer is formed like a film; the filter layer can be a foil or a membrane, for example. The filter layer according to the invention is therefore also referred to synonymously as a film or membrane. The filter layer can be produced with the smallest possible thickness, which means that the length of the pore channels can be reduced compared to conventional screen fabrics. As a result, with comparatively small cross sections of the pore openings, a smaller force is advantageously required in order to transfer the substances from one side of the filter layer to the other. The required pressure is reduced and thus no longer has an adverse effect on complex biological systems such as primary cells.

The polymeric material of the filter layer can be natural or artificial, eg a plastic, cellulose or polylactides. It is essential that the polymeric material can be perforated, ie is suitable for the formation of pores. The filter layer can include renewable, regenerated and/or recycled materials. The filter layer preferably has pores whose defined shape is selected from the group consisting of round, oval, angular shapes or free shapes that are produced by a combination of the round, oval and angular shapes. The pores therefore have properties that the meshes of conventional screen fabrics, which are always angular due to their construction, do not have. The pore shapes can all be provided in one filter layer at the same time. The pores can be provided in a filter layer with uniform or non-uniform distribution.

The microstructured surface of the filter layer preferably has a number of supporting, controlling and/or regulating structures in the nanometer-micrometer range. The microstructured surface of the filter layer is also referred to as a microstructured functional surface. The structures are designed to control the filtration of the fluid medium. The microstructures can, for example, advantageously control and monitor the permeability of the filter layer, monitor the stability of the filter layer and emit signals upon contact with defined substances. The microstructures can, for example, also be components that are known from microoptics, microfluidics, photonics and other specialist areas. Microstructures enable properties, e.g. when using a device produced according to the invention as a filter device in purification processes, which conventionally cannot be provided in a corresponding quality by passive microfluidic components based on filters or simple hydrodynamic processes.

The microstructured functional surface advantageously enables the device according to the invention to be used in filtration or separation devices in the nano, micro to millimeter range and in systems in which the microstructured surface is used as a permeable partition wall between at least two systems. The invention improves the use of filtration devices with regard to separating biological and non-biological mixtures of substances, which primarily contain pressure-sensitive components, such as primary cells, Bacteria, bioparticles or vesicles, in the micro and nanometer range. In addition to general filtration applications, the invention opens up and improves use in medically complex systems that require certified and highly regulated use through the defined size and distribution of the microstructures.

The structures are preferably selected from a group with raised geometries, recessed geometries and feeding geometries. The microstructures are referred to as geometries here in the sense that they are supporting geometries. The capillary flow is controlled, ie the filtration via the filter layer according to the invention is supported, e.g. accelerated or slowed down. For example, small particles can quickly migrate through the pore and large particles simply lack the time or flow to get to the pore in the first place.

Preferably, the structures with raised geometries include hemispheres, pyramids, rounded-topped pyramids, cones, rounded-topped cones, and/or cylinders. Advantageously, raised geometries not only influence the flow against the pore, but also the flow over the pore. In this technical context, which comes into play, for example, in a cross-flow filter, blocking of the pores could be prevented. This improves the service life of the filters, since the pores do not clog as quickly and therefore do not have to be replaced as quickly.

Preferably, the deepening geometries are non-perforating ablations. The advantages correspond to those of the raised geometries.

The feeding geometries also preferably have a shovel-like design. In other words, the supporting geometries can be designed in the form of blades, that this is a feed to the pore.

Preferably in the device the filter layer is embedded in an upper and lower layer. There is a feeding line in the upper layer and the lower layer is formed with a fluid medium leading away conduit so that the filter layer is in the fluid medium flow path. This advantageously allows the device to be used in systems that include filtration or osmosis of a fluid medium, for example in cell cultivation systems or dialysis facilities.

The pores are preferably arranged in such a way that they form squares in the surface of the filter layer, which are separated by webs. In other words, these webs designate the areas between the squares. The webs are advantageously suitable for arranging further elements.

Conductor tracks suitable for resistance measurement (e.g. metallic strain gauges) are preferably arranged in the matrix (e.g. by additive manufacturing such as printing) in the filter layer. At least one interconnect is particularly preferably arranged in the area of said webs. The interconnects can be used in combination with the expansion of the porous filter layer to measure resistance. The determination of the resistance is based on the change in length and cross-section of metal strain gauges. If the measuring strips are stretched, the resistance increases. The resistance measurement can be used to control various process sequences. For example, if the resistance increases, it can be concluded that the filter layer is blocked. If the resistance is actively measured, it becomes possible to control the process directly. Options in the process chain could be reducing a flow through the device, the device can be backwashed or a corresponding system with the device can even be switched off in order to prevent a breakthrough. If the microporous carrier layer is even destroyed, the flow through the device can be stopped directly.

The pores in the filter layer preferably have a size in the range from 250 nm to 5 mm, in particular in the range from 250 to 1000 μm. The filter layer according to the invention can thus be used much more selectively than, for example, conventional screen fabric, in which pores below 1 μm with precise selectivity cannot realistically be produced from screen fabric. A second aspect of the invention relates to a system with a device according to the invention, comprising at least one line for a fluid medium, in which the device for filtering the fluid material is arranged. The device is used in the system as a filtration device and is suitable for both cake and cross-flow filtration. The device can be used as a sieve or filter.

For example, the system enables advantageous use in laboratory filters, in filter cascades, in systems for separating functionalized bioparticles, in cell culture approaches (for skin models, 3D epithelial cultures, investigations of chemotaxis, transmigration assays or e.g. in transport and polarity studies), in extracorporeal systems (e.g. in dialysis systems, or in systems in which personalized cells are used, cultivated as a monolayer and thus serve to support the body's own functions) and in filter systems for the enrichment of bacteria for diagnostic purposes.

For example, biological films can advantageously be grown in the system. In this sense, the device can be used as a rearing matrix for biological systems. The pores of the filter layer can be used, for example, to supply and/or remove metabolic products from living beings. The device can also be used to determine biological metabolic parameters. When cultivating a monolayer (means that the cells attach themselves to an available substrate, glass surfaces or the plastic bottom of the culture vessel and can only multiply and spread under these conditions. They are the common culture and growth form for most animal cells .) on the functional surface, the formation of the natural polarity and morphology of the cells are supported. At the same time, when used in cell culture inserts, the cells can be supplied and removed through the functional surface.

The device according to the invention with microstructured functional surfaces can advantageously be used in filtration or separation devices in the nano, micro to millimeter range as well as in Systems are used in which the microstructured surface is used as a permeable partition between at least two systems. The invention improves the use of filtration devices with regard to separating biological and non-biological mixtures of substances, which primarily contain pressure-sensitive components, such as primary cells, bacteria, bioparticles or vesicles, in the micro- and nanometer range. In addition to the general filtration application, the invention, through the defined size and distribution of the microstructures, opens up and improves the use in medically complex systems that require a certified, highly regulated application.

The system according to the invention is preferably designed as a lab-on-chip system. In lab-on-chip systems, the microstructured surface of the filter layer of the device acts advantageously in the system in terms of the filter function. Conventionally, when analyzing whole blood, for example, in many cases the blood is first filtered in order to be able to carry out subsequent analyzes from the blood serum. Since the sample material is partially transported in these microfluidic systems with the aid of capillary forces, it is not possible to work with high pressures in order to realize the separation of cellular components and the blood serum. Filter materials with low porosity, such as filter fabric or plasma membranes, can therefore not be used. With filter fleeces, which are often used for the separation of blood components, it must also be ensured that, in addition to absorbing liquid, which is not insignificant with very small sample volumes of, for example, 20 μl, they sometimes bind proteins and thus the analytes from the blood serum non-specifically. In addition to the filter materials, the separation could also be supported with centrifugation. Since a centrifuge is required for this process and thus requires additional technical effort, the required simplicity of these systems is negated. In contrast to this, in a lab-on-chip system with a device according to the invention, the arrangement and the geometry of the pore openings can be specifically adapted to the microfluidic filtration. In addition, the functional interface can be selected and modified that no non-specific binding of proteins takes place. The functional surface thus opens up new construction possibilities and thus a range of applications.

A third aspect of the invention relates to a method for producing a device with a filter layer having at least one porous and microstructured surface, with the steps:

- providing the device in a device comprising a laser, which is designed to apply structures in the filter layer by means of a laser,

- processing the surface of the filter layer with the laser, the material of the filter layer being perforated by forming pores,

- Modifying the surface of the filter layer by at least one additive method and/or a chemical method.

The method advantageously makes it possible to produce openings on the surface of the filter layer, so that a filter layer according to the invention with the above-mentioned advantages can be provided. Accordingly, laser ablation offers decisive advantages when structuring the filter layer: targeted distribution of the pores on the surface of the filter layer, defined ratios of perforated to non-perforated areas, controlled shape of the pores. The method preferably includes a further step in which the edges of the filter layer are embedded in a material suitable for injection moulding, i.e. by an injection molding process, so that it can be further processed, e.g. as a filter in a component. Embedding can take place between the individual steps.

Advantageously, the filter layer can be provided with the openings both before and after processing or incorporation into the intended component. The process can be designed in such a way that the filter layer can be equipped with a support structure. Backing sheets could be used that are formed in a roll-to-roll process were manufactured. At the same time, the carrier material, off the roll, can be fed directly to the manufacturing process (e.g. injection molding, stamping). The holding structures or components with an embedded carrier layer for the subsequent perforation could be, for example, rings, rectangles or free forms, which on the one hand enables and supports the planar processing of the carrier layer and also allows an unhindered subsequent perforation. Carrier layers that have already been modified can be directly injected and encapsulated in more complicated components such as cylinders, in addition to simple components such as rings or rectangles.

In addition, post-processing of the filter layer in the component is possible. The embedding of corresponding filter layers is accordingly undemanding and offers the production process the advantage that a large number of workable blanks can be manufactured automatically. Advantageously compared to other methods, the potential microstructuring does not have to be defined from the beginning of production and thus allows greater flexibility with regard to later usability. At the same time, the arrangement of the microstructuring can be application-specific and does not have to be the same for every process. This is the main difference to all products previously available on the market. The manufacturing process can be customized to a high degree and allows systems to be manufactured cost-effectively and specifically that are not determined by the starting material. In conventional processes, pores and mesh sizes have to be defined from the start. Since laser ablation is a process that removes material, microstructuring can be carried out as a downstream process. This enables process-related customization, which allows the cost-effective implementation of small and small series.

In the method according to the invention, the surface of the filter layer is additionally modified by additive methods and/or chemical modifications and/or biological modifications. The modification can take place both before and after the laser ablation. An additive method is z. a 3D print. Additional supporting, controlling or regulating structures can be attached and applied to the surface in a particularly advantageous manner by means of additive processes.

The use of laser ablation also has the decisive advantage that the surface can be modified in the process in an application-specific manner and can therefore be highly individualized. The manufacturing process is application-oriented and is therefore no longer determined by the available starting material. Access to very small and small series in order to implement special applications is therefore much easier to implement. At the same time, the combination of laser ablation and additive processes on the nano and micrometer scale can enable actively controllable hydrodynamic processes. The functional surface can be used as a partition or support matrix for growing biological films. The functionality of the microperforation by means of laser ablation enables the supply and disposal of the biological component to be permeable. At the same time, the modifiability of the carrier materials helps to determine and control biological parameters using additive processes.

In the method, laser ablation and additive methods for producing additional pore structures are preferably carried out in combination in a staged process. The pore opening could be generated in such a way that the opening can face the direction of a liquid flow or can face away from the flow direction.

The invention is explained in more detail with reference to the figures. Show it

FIG. 1 shows a schematic representation of an embodiment of a device according to the invention.

FIG. 2 shows a schematic representation of a surface of a filter layer with a defined shape and distribution of the pores. FIG. 3 shows a schematic representation of a surface of an embodiment of the filter layer, together with an enlarged section.

FIG. 4 shows a comparative schematic representation of the surfaces of a filter layer without (A) and with webs (B).

FIG. 5 shows a schematic representation of a surface of an embodiment of a filter layer with applied interconnects, together with an enlarged section.

Figure ß Representation of different pore shapes in a surface of a filter layer (a - g).

FIG. 7 Representation of different possibilities for the arrangement of pores in the surface of a filter layer (a-e).

FIG. 8 shows a schematic representation of a further embodiment of a device according to the invention.

FIG. 9 shows a schematic representation of a further embodiment of a device according to the invention.

FIG. 10: A flow diagram of an embodiment of the method according to the invention.

FIG. 11: a flow chart of a further embodiment of the method according to the invention.

1 shows an embodiment of a device 1 according to the invention. The device 1 has a housing 2 in the embodiment according to FIG. 1a. A filter layer 10 is arranged in the interior 3 of the housing 2 . The filter layer 10 is arranged in Fig. 1a without a support matrix, i.e. it was incorporated directly into the housing 2 during the manufacturing process.

In the embodiment according to FIG. 1b, the housing 2 has a housing upper part 4 and a housing lower part 5, which are reversible with one another are connected, for example by a screw cap. Here the filter layer 10 is arranged in the upper area of the lower housing part 5 . Here, the filter layer 10 is arranged on an insert 6, which functions as a support matrix for the mechanical stability.

In an alternative embodiment, the filter layer 10 can also be combined with the insert s in such a way that the filter layer 10 is incorporated directly into the insert 6 and is then firmly connected to it. If the housing parts 4, 5 are each modified with two inlets and outlets, the device 1 can be used as a cross-flow filter.

In Fig. 2, the filter layer 10 is shown. The filter layer 10 consists of polylactides. Alternatively, the filter layer 10 can also be made from another suitable natural or purely synthetic polymer or a mixture of corresponding polymers.

The thickness of the filter layer 10 is 500 μm. Alternatively, the layer thickness can also be thinner or thicker; it can be chosen to meet the desired requirements. The dimensions in height and width can also be freely selected according to a planned application and can be e.g. 10 cm (height) and 8 cm (width).

The filter layer 10 has a number of pores 20 . The pores 20 are rectangular in the surface 30 of the filter layer 10 and are arranged in an ordered pattern in defined rows. The pores 20 have dimensions of 250-1000 μm.

FIG. 3 shows the filter layer 10 according to FIG. 2 in more detail. For this purpose, the filter layer 10 is shown with an enlarged section A. The pores 20 are arranged in rectangular squares 21 of 24 (4×6 rows) pores 20 . A distance is formed between the squares 21 in each case. The squares 21 are evenly distributed over the surface 30 of the filter layer 10 .

In Fig. 4, two configurations of the pore distribution are shown in comparison. In Fig. 4A, the pore distribution in the filter layer 10 corresponds to Fig.

1 and 2. The pores 20 are arranged in squares 21 which are demarcated but closely spaced. In Fig. 4B are the distances formed between the squares 21 more clearly. The areas between the squares 21 are also referred to as webs 22 .

The webs 22 act as placeholders, on which e.g. interconnects 23 can be arranged (Fig. 5). The nature of the interconnects 23 allows resistances to be dissipated. Conductors 23 can be arranged in all webs 22 . Alternatively, interconnects can also only be arranged in a few webs. An enlarged section in Fig. 5 shows a more detailed view of the pores 20 and interconnects 23.

The pores 20 can have any other shape besides the rectangular shape shown in FIGS. 2-5. 6 shows various possible pore shapes by way of example: a) rectangular, b) cross-shaped, c) circular, d) circular and rectangular combined, e) oval, f) oval and rectangular combined, g) triangular and rectangular combined essentially triangular). Other shapes are possible.

Possibilities are shown in FIG. 7 as to how the pores 20 of the same or different shapes can be arranged in the filter layer 10 . The arrangements are each shown as a square 21 . In Fig. 7a triangular pores 20 are arranged alternately with pointed or flat sides to each other. In FIG. 7b, in contrast to a), triangular pores 20 are arranged in such a way that they are arranged with the pointed sides offset to one another, so that the points lie next to one another and not one another. In FIG. 7c, rectangular pores 20 are arranged in a square 21 such that 8 pores 20 are arranged in the upper and lower rows with the long sides facing each other and three pores 20 are arranged in each case with the short sides facing each other in the two middle rows. In FIG. 7d the pores of the two middle rows are arranged as in FIG. 7c. The pores 20 of the top and bottom rows are arranged with the long sides to one another, similar to FIG. 7c, but in a slightly inclined configuration (top row tilting to the left, bottom row tilting to the right). In FIG. 7e, three rows of three rectangular pores 20 each are arranged with the short sides facing each other. A row with circular pores 20 is arranged alternately between the rows with rectangular pores 20 . It is clear that the pore shapes and the arrangements of the pores 20 are not limited to the examples shown. Further possible combinations in the formation and arrangement of the pores 20 are possible.

In Fig. 8 an embodiment of a system 40 is shown, which has a device 1 with two filter layers 10, namely a first (lower) filter layer 11 and a second (upper) filter layer 12. The system 40 in Fig. 8 represents a sieve system A connector 41 connects the device 1 to a collecting vessel 42 and enables a filter support system to be connected. A funnel 43 is arranged in the upper area of the system 40, which is provided for enlarging a feed volume of a medium to be filtered.

The second filter layer 12 can be arranged above the first filter layer 11 in a leakproof manner. The two filter layers 11, 12 differ in at least one parameter, at least in the porosity, so that the porosity of the second filter layer 12 is greater than that of the first filter layer 11. The second filter layer 12 is optional, i.e. the system 40 works also alone with the first filter layer 11 .

Another embodiment of the system 40 is shown in FIG. The system 40 in FIG. 9 represents a sieve system for a bottle-top filter. The first filter layer 11 is arranged in a first sieve device 45 and the second filter layer 12 is arranged in a second sieve device 46 arranged above the first sieve device. Here, too, the two filter layers 11 , 12 differ in at least one parameter, namely at least in the porosity, so that the porosity of the second filter layer 12 is greater than that of the first filter layer 11 . Here, too, the second filter layer 12 is optional (correspondingly the second screening device 46), i.e. the system 40 also functions with the first filter layer 11 alone.

In a method according to FIG. 10 for producing a filter layer 10, in a first step S1 a blank of a layer made of polylactides is provided in a suitable device familiar to a person skilled in the art. The blank can come from a roll, for example, ie by a roll-to-roll process be mapped. The blank can be held by a holding structure, for example.

In a second step S2, the blank is processed using a laser device in a laser ablation method. In the process, pores are inserted into the blank.

In a third step S3, the blank (to be referred to now as the filter layer 10) is fed directly to the injection molding process. The edges of the filter layer 10 are covered with a material, the filter layer 10 is embedded, so to speak, so that it can be used as a filter, for example. Said material is suitable for injection moulding; it may, for example, comprise the same material as the filter layer 10, or a different material known to those skilled in the art, e.g., plastic. The filter can in turn be installed in a component.

In a fourth step S4, the surface of the filter layer 10 is additionally modified by additive methods. Additionally or alternatively, the surface can also be chemically modified. Steps S2, S3 and S4 are interchangeable, i.e. the modifications by additive methods can also be carried out before the laser ablation.

In a further embodiment of the method, which is also explained with reference to FIG. 10, the filter layer 10 according to the invention is converted during processing into a component which is to have the filter layer 10. In this case, step S1 is carried out as in the method according to FIG. In step S2, the blank is injected into a component and then processed by laser ablation in step S3. Step S4 then again corresponds to step S4 according to the method of FIG. 10. The modification by means of additive methods can also take place here both before and after the injection molding, as well as before the laser ablation. The finished component can in turn be installed as an insert in another component

The insertion into a component can also take place prior to laser ablation. In other words, step S3 in FIG. 10 can also be swapped with step S2. The filter layer 10 can thus be processed both before and after it is inserted into a component. In one embodiment of the method according to FIG. 11, the same as in the method according to FIG. 10 is carried out in an S1. In step S2, the blank is injected into a component. In a third step S3, the surface of the blank is chemically modified. In a fourth step S4, the surface of the blank is machined by laser ablation. In a fifth step S5, the filter layer 10 is modified by additive methods. Here, too, the modification of the foil surface takes place specifically after the injection molding process, the modification of the foil surface with additive processes can take place both before and after the laser ablation. The finished components can in turn be installed as an insert in another component.

Reference List

1 facility

2 housing

3 housing interior

4 Housing top

5 lower part of the housing

6 depositors

10 filter layer

11 first filter layer

12 second filter layer

20 pore

21 square of pores

22 footbridge

23 meridian

30 surface of the filter layer

40 systems

41 connector

42 collection vessel

43 funnels

45 first screening device

46 second screening device

A enlarged detail

Claims

patent claims 1. Device (1) for filtering a fluid material, comprising a filter layer (10) having at least one polymeric material and having at least one porous and microstructured surface (30) having pores (20) with a defined shape that are specifically formed in the material of the Filter layer (10) are distributed so that the filter layer (10) has perforated and non-perforated areas. 2. Device (1) according to claim 1 or 2, wherein the defined shape of the Pores (10) are selected from the group consisting of round, oval, angular shapes or free shapes that are produced by a combination of the round, oval and angular shapes. 3. Device (1) according to one of the preceding claims, in which the microstructured surface (30) has a number of a number of supporting, controlling and/or regulating structures in the nanometer-micrometer range, which are designed to control the filtration of the fluid medium. 4. Device (1) according to claim 3, in which the structures are selected from a group with raised geometries, recessed geometries and feeding geometries. 5. Device (1) according to claim 4, wherein the structures with raised geometries include hemispheres, pyramids, rounded-topped pyramids, cones, rounded-topped cones, and/or cylinders. 6. Device (1) according to claim 3 or 4, wherein the deepening geometries are non-perforating ablations. RECTIFIED SHEET (RULE 91 ) ISA/EP 7. Device (1) according to claim 3, 4 or 5, wherein the feeding Geometries have a shovel-like formation. 8. Device (1) according to any one of the preceding claims, wherein the filter layer (10) is arranged between an upper and lower region of the device and the upper and lower regions form a supply line and a lead-out line for the fluid medium, so that the filter layer (10) is in the flow path of the fluid medium. 9. Device (1) according to any one of the preceding claims, wherein the pores (20) of the filter layer (10) are arranged in such a way that webs (22) are arranged between areas with pores (20). 10. Device (1) according to claim 6, in which at least one interconnect (23) is arranged in the region of the webs (22). 11. Device (1) according to any one of the preceding claims, wherein the pores (20) have a size in the range of 250 nm-5 mm, in particular in the range of 250-1000 μm. 12. System with a device (1) according to any one of claims 1-11, comprising at least one line for a fluid medium, in which the device (1) for filtering the fluid material is arranged. 13. System according to claim 12, which is designed as a lab-on-chip system. 14. A method for producing a device (1) with a filter layer (10) having at least one porous and microstructured surface, with the steps: RECTIFIED SHEET (RULE 91 ) ISA/EP - providing the device in a device comprising a laser, which is designed to apply structures in the filter layer by means of a laser, - processing the surface of the filter layer with the laser, the Material of the filter layer is perforated by forming pores, - Modifying the surface of the filter layer by at least one additive method and/or a chemical method. RECTIFIED SHEET (RULE 91 ) ISA/EP