EP2480386A1

EP2480386A1 - Partially perforated microstructured molded body and method for producing the same

Info

Publication number: EP2480386A1
Application number: EP10709454A
Authority: EP
Inventors: Andreas Schober; Jörg HAMPL; Frank Weise
Original assignee: Technische Universitaet Ilmenau
Current assignee: Technische Universitaet Ilmenau
Priority date: 2009-09-27
Filing date: 2010-02-24
Publication date: 2012-08-01
Also published as: WO2011035937A1; DE102009044113A1

Abstract

The invention relates to a partially perforated microstructured molded body (01) such as it can for example be used to cultivate biological cells or for use as a sieve structure. The invention further relates to a method for producing a molded body (01) of the above type. The method according to the invention comprises a first step during which a deformable film (01) is made available. In a second step, the film (01) is partially stretched, thereby forming stretched sections (02; 03) in which the film (01) has a reduced thickness. Limitation of the stretching to some sections (02; 03) of the film (01) results in undeformed sections (07) of the film (01) remaining. The method according to the invention further comprises a step during which microstructures (03) are formed in at least some of the thinner stretching sections (02; 03) of the film. Pores are produced in at least one of the thinner stretching sections (03) of the film (01), while at least some of the undeformed sections (07) remain impermeable. The undeformed sections (07) of the film (01) remain impermeable since no continuous pores are produced in said sections.

Description

Partially perforated microstructured molding and process for its production

The present invention relates to a partially perforated ^¬ th microstructured molded body, such as can be used for example for the cultivation of biological cells or as a sieve structure. Furthermore, the invention relates to a method for producing such a shaped body.

DE 102 03 250 C1 shows a method and a device for microstructuring polymer films. The film to be structured is preheated to a temperature below the glass point of the film material and passed together with at least one die plate having an embossed structure between two rollers heated to a temperature above the glass point. The rollers are pressed simultaneously against ^¬ each other to the embossed structure einzuprä ^¬ gene into the film. The tooling plate is separated after cooling again from the film.

From DE 10 2007 050 976 AI a method for forming a film is known in which the film to be formed firmly with a mold backdrop, the at least one breakthrough

has, is connected. Subsequently, portions of the film to be formed are subjected to a physical or chemical modification. The film connected to the mold is placed in a mold and subjected to a pressure medium, which molds the film into the opening of the moldings.

DE 10 2004 035 267 B3 shows a microstructured molding and a process for its production. The form- body consists of a film, at least one hollow ^¬ structure is introduced into the. The hollow structure preferably has an omega structure. The entire shaped body, ie both the film and the hollow structures, have a multiplicity of pores whose diameter preferably assumes a value between 10 nm and 10 μm. The pores are randomly distributed over the entire ie molded body over the foil and the Hohlstruktu ^¬ reindeer, wherein it may happen that individual pore overlap. FIG. 7 of DE 10 2004 035 267 B3 clearly shows that the pores are formed both in the hollow structure and in undeformed regions of the film. To introduce the pores, the film is exposed to ionizing radiation. The ions leave latent traces, which lead to pores through an etching process. A disadvantage of this solution consists initially in the fact that the pores are formed in the entire molded body. In order to prevent the pores from being formed in the entire shaped body, it is further proposed to use a mask in order to limit the irradiation of ions to certain areas of the foil. The mask must map the exact to be provided with pores preparation ^¬ che, whereby an increased effort.

The object of the invention, starting from the prior art, is to provide a microstructured molding and a process for its production which is only partially perforated and can be produced with little effort.

The above object is achieved by a method for producing a partially perforated microstructured shaped body according to the appended claim 1. The object is further achieved by a microstructured molding according to the attached independent claim 6. The method according to the invention serves to produce a microstructured shaped body which can be used, for example, for culturing biological cells or as a sieve structure. The produced molding is part ^¬ be perforated, ie having only some areas of the Formkör ^¬ pers pores. The method according to the invention initially comprises a step in which a deformable film is provided. The thickness of the film can be chosen largely arbitrarily, for example in the range between

1 ym and 1 mm. In a further step of the method according to the invention, the film is partially stretched, for example by expanding some areas of the film by pressing these areas into a hollow mold to be filled. There are drawing areas in which the film has a reduced thickness. The reduced thickness will in many cases not be constant within the drafting range but will decrease toward a range of maximum draw. Restricting stretching to some areas of the film leads to unformed preparation ^¬ che the film remain. In these undeformed areas, the thickness of the film has not or only slightly changed. The method according to the invention furthermore comprises a step in which microstructures are formed in at least some of the thinned draw regions of the film. The microstructures may be, for example, omega structures or channels. The partial

Stretching of the film and the formation of microstructures can be done together, for example by pressing the film into a hollow mold to be filled. According to the invention, pores are produced in at least one of the thinned draw regions of the film, while at least some of the undeformed regions remain impermeable. The undeformed Regions of the film remain opaque, since no continuous pores are generated in this preparation ^¬ chen. Preferably, all undeformed areas of the film remain impermeable. Also, the pores are preferably formed in all of the thinned stretch regions of the film insofar as these areas are one

Have thickness that is smaller than a limit thickness, and inasmuch as these areas are not covered or otherwise inaccessible. A particular advantage of the method according to the invention is that a partial perforation, i. H. limited production of pores is made possible only by partially stretching the film, whereby the film has areas of different thicknesses. The difference in thickness of the film is exploited to limit the perforation of the film to some areas of the film. By contrast, the undeformed areas of the film remain almost or completely impermeable. Generating the pores in the at least one of the diluted ones

Enforcement areas are preferably performed by applying a perforation method to create pores on at least some of the undeformed areas and on at least some of the thinned stretch areas of the film, with parameters of the perforation method being measured so as not to create voids in the undeformed areas. The perforation method is preferably applied to the entire film. One or more parameters of the perforation process, such as intensity or force, are calculated so that complete pores are formed only in regions of the film whose thickness is less than the limit thickness. Regions of the film which have a thickness which is Minim ^¬ least as large as the limit thickness can be obtained by the Perfora- tion process with the selected parameters are not, or at least not completely pierced, so that no continuous pores created by ^¬. The perforation process can be any mechanical or chemical process which is suitable for producing pores of a film and can be adjusted such that the pore formation is dependent on the thickness of the film.

The perforation method preferably comprises a substep in which the some of the undeformed regions and the at least one of the thinned stretch regions of the film are irradiated with ionizing radiation, thereby producing ion transmission holes in the film. The intensity of the ionizing radiation is so dimensioned that complete ion transmission only occurs in the dilute stretching regions exposed to the irradiation. In the undeformed areas of the film whose thickness is greater than the limit thickness, the ions do not fully pass through the film, so that no continuous ion transmission occurs. The ions are already held up in the surface of the film or in a central region of the film, so that at most ion shots arise. The ion shots cause a structure of the material of the film in the region of the respective ion penetration is destroyed over the entire thickness of the film. In a further step of the perforation process, the film is etched, for example by placing the film in an etching bath. The etching of the film leads to the material of the film being removed in the region of the ion passages, so that continuous pores with a diameter of, for example, 2 μm are formed.

In a particular embodiment of the method according to the invention when irradiating the film, the film with a Mask covered to additionally limit the areas to be provided with pores. For example, the mask can be used to prevent pores from forming in selected ones of the thinned draw regions having a thickness that is less than the limit thickness. The mask is in accordance with Inventive ^¬ but not necessary, to ensure that the pores in the undeformed regions of the film not arise.

The partial stretching and shaping of the microstructures in the film is preferably carried out by a rule thermoplasti ^¬ deformation process. The thermoplastic deformation process requires that a thermoplastic be used as the material for the film. The film is to be placed between a first mold ^¬ half and a second mold half. The second mold half has a macrostructured hollow shape in which microstructured hollow fores are formed. The first mold half is ^¬ seal against the foil, whereby a separated space between the first mold half and the film is formed. The first mold half and the second mold half are to be pressed together with the film in between. The

Sealing the first mold half to the film and compressing the first mold half and the second mold half can be done together, for example, by pressing the film against a seal on the first mold half. In a further substep, the film is heated to at least a glass transition temperature of the thermoplastic, so that the film becomes thermoplastically deformable. An overpressure is created between the first mold half and the film, which presses the film into the macrostructured mold and into the microstructured molds. At the same time this results in the film being stretched. The stretching results in particular from the macrostructure, which leads to a significant elongation of the film leads. The macro-structured hollow shape may be cuboid in the simplest case, the forming of the parallelepipedic shape serves, in particular, the pull is to be deformed preparation ^¬ surface of the film from the original position, thereby stretched to be deformed areas and drawn, so that there is a thinning , Regions of the film that are located outside the macrostructured mold are not deformed. In this case, it may be, for example, a rectangular-type ^{delimiting frame} which delimits the cuboidal mold. In another

Partial step is to cool the film so that the temperature of the film falls below the glass transition temperature of the thermoplastic and the film retains its preserved shape.

The microstructured molding according to the invention initially comprises a film, from which it is fully formed ^¬ constantly in the simplest case. The film is divided into undeformed areas and thinned draw areas. The film may for example have a rectangular basic shape, the frame is undeformed, while a rectangular Innenbe ^¬ rich is stretched and has a smaller thickness. ^¬ at least some of the diluted Verstreckungsbereiche microstructures are formed. For example, the micro ^¬ structures may be arranged in a matrix in the rectangular inner area of the film. At least in one of the diluted ones

Drawing areas are formed pores. The pores are holes, which allow, for example, a passage of gases or liquids. At least some of the undeformed areas have no pores and are therefore impermeable. Preferably, none of the non ^¬ formed regions on pores, resulting in the non-deformed areas are all opaque. A particular advantage of the microstructured shaped body according to the invention is that it can be adapted to a large extent to the intended application, in particular by having pores only where they are required, and consequently no pores where they possibly affect the intended application.

In a preferred embodiment of the microstructured shaped body according to the invention, the dilution in the drawing regions of the film is increasingly formed beginning at the edges of the undeformed regions into the microstructures. The pores are present only in those regions of the thinned draw regions which have a thickness that is less than the limit thickness. Consequently, there may also be regions of the thinned stretch regions which have no pores, since the thickness of the film in these regions is at least as large as the boundary thickness. There may also be regions of thinned stretch regions having a thickness that is less than the boundary thickness but that does not have pores, for example, because these regions are concealed. Depending on the manufacturing process chosen, the undeformed regions and those regions of the thinned stretch regions that do not have pores may have pores, for example in the form of tiny craters. In any case, the pores do not form continuous pores.

In a preferred embodiment of the microstructured shaped body according to the invention, only a few subregions of the microstructures have pores. This is due to the fact that these portions of the microstructures have a thickness which is less than the limit thickness, while other part preparation ^¬ surface of the microstructures have a thickness which is at least as large as the limit thickness is. In this embodiment of the microstructured shaped body according to the invention, the pores are present only in those partial areas of the microstructures in which they are required for the intended application.

The microstructured molding of the invention is before Trains t ^¬ carried out such that portions of the microstructures that are obscured by other portions of the microstructures that are opaque, since they have no pores. The

Forming the microstructures leads to the different subareas of the microstructures having different orientations. Some of the sections have one

Orientation perpendicular to the orientation of the entire film. Not all portions of the micro ^¬ structure therefore can be seen from an angle perpendicular to the surface of the film Haupterstreckungs- because they are obscured, for example, due to the vertically aligned orientation, or by other portions of the microstructures. The hidden parts of the microstructures have no pores, which can be caused firstly by the production and at the other hand, ^¬ can be used individually adapted to the intended application fit design. In a preferred embodiment of the microstructured molding of the invention, the diluted Verstre- are ckungsbereiche within a macro-structure of the film being formed ^¬. The macrostructure may, for example, have the shape of a cuboid or a cylinder, the thinned drawing regions being formed in particular in the region of the base surface of the cuboid or of the cylinder. The macro ^¬ structure can serve in particular to the microstructured molded body in an undeformed area outside the Macrostructure and to divide into a dilute stretch region within the macrostructure.

Further advantages, details and developments of the invention will become apparent from the following description of several

Embodiments of the invention, with reference to the drawing. Show it:

1 shows a preferred embodiment of a microstructured shaped body according to the invention in one

Cut looks;

FIG. 2 shows a detail of the microstructured shaped body shown in FIG. 1; FIG.

FIG. 3 shows a microstructure of the shaped body shown in FIG. 1; FIG.

4 shows a detail of the microstructure shown in FIG

pores;

FIG. 5 shows a detail of the microstructure shown in FIG. 3. FIG

craters; 6 shows a first step of a preferred embodiment of the method according to the invention for producing a partially perforated microstructured shaped body;

7 shows a second step of the preferred embodiment of the method according to the invention;

8 shows a third step of the preferred embodiment of the method according to the invention;

9 shows a fourth step of the preferred embodiment of the method according to the invention; 10 shows a fifth step of the preferred embodiment of the method according to the invention;

11 shows a sixth step of the preferred embodiment of the method according to the invention;

FIG. 12 shows a seventh step of the preferred embodiment of the method according to the invention; FIG. and

13 shows an eighth step of the preferred embodiment of the method according to the invention. Fig. 1 shows a preferred embodiment of a fiction, modern ^¬ microstructured molded body 01 in a sectional view. The microstructured shaped body 01 according to the invention is formed by a film of polycarbonate. The micro-structured form ^¬ body 01 has a macrostructure 02 and microstructures 03. The individual microstructures 03 form cavities which are arranged in the form of a matrix. The cavities formed by the microstructures 03 are used for the cultivation of biological cells. The macrostructure 02 leads to the area of the microstructures 03 being offset. A detail marked by a circle

06 of the microstructured shaped body 01 according to the invention is shown in FIG. 2. The microstructured mold body 01 has a non-deformed area 07 outside of the macrostructure 02 and outside the micro ^¬ structures 03.

FIG. 2 shows the detail 06 of the microstructured shaped body 01 shown in FIG. 1. In the undeformed area 07, the film forming the microstructured shaped body 01 has a thickness of approximately 100 μm. The film 01 is formed by the macrostructure 02 and by the microstructures 03 forming

Cavities stretched, whereby the thickness of the film 01, starting from the undeformed area 07 on the macrostructure 02 to into the cavities 03 continuously decreases. In a lower region 08 of the cavity 03 shown, which for

Illustrated by a hatched area, the thickness of the film 01 is only a fraction of the thickness of the film 01 in the undeformed area 07th

FIG. 3 shows the microstructure 03 shown in FIG. 2 in a further detailed view. The thickness of the film 01 also decreases significantly even within the cavity 03. An area 09 of the cavity 03 marked by a circle is shown in detail in FIG. 4. A region 11 of the cavity 03 marked by a circle is shown in detail in FIG. 5.

FIG. 4 shows the region 09 of the cavity 03 shown in FIG. 3 in detail. The film 01 is in a region of the cavity 03 in

Section shown in which the thickness of the film 01 is minimal. In this area, the film 01 has a plurality of pores 12. The pores 12 may serve, for example, the passage of gases or liquids. The pores 12 have a diameter of about 2 ym.

FIG. 5 shows the region 11 of the cavity 03 shown in FIG. 3 in detail. In the area 11, the film 01 has a maximum thickness occurring in the cavity 03. In the region 11 craters 13 are formed, which are formed by projections of pores. In any case, the craters 13 are not continuous, so that liquids or gases which enter the craters 13 can not pass through the film 01. FIG. 6 shows a first step of a preferred embodiment of the method according to the invention for producing a partially perforated microstructured shaped body. In the first step of the preferred embodiment of the invention According to the invention, a first mold half 21 and a second mold half 22 and a deformable film 23 are provided. The first mold half 21 and the second mold ^¬ half 22 are made of a solid temperature-resistant material, such as glass or metal. The first mold ^¬ half 21 has opposite the film 23 has a recess 24 in order to create a cavity between the film 23 and the first mold half 21. This cavity formed by the recess 24 can be sealed with respect to the film 23 by means of sealing elements 26. In the first mold half 21, a first channel 27 is formed, which leads from the outer of the first mold half 21 to the recess 24. The second mold half 22 has a macrostructured hollow mold 28 formed by a recess. The macrostructured hollow mold 28 has essentially the shape of a flat

Cuboid on. Within the macrostructured hollow mold 28, namely in a base area of the cuboid shape of the macrostructured hollow mold 28, microstructured hollow molds 29 are formed. The macro-structured hollow form 28 and the micro-structured ^¬ molds 29 form a negative shape of the microstructured molding. The microstructured molds 29 are recesses with a diameter of about 300 ym. Typical microstructures have dimensions in the range of a few ym to a few mm. In the second mold half 22, a second channel 31 is formed, which from the outer of the second mold half 22 to one coming into contact with the film 23 in contact

Area of the second mold half 22 leads.

The film 23 is made of polycarbonate. As a material for the film 23, other thermoplastic polymers are suitable. Fig. 7 shows a second step of the preferred embodiment of the method according to the invention. The first mold half 21 and the second mold half 22 to be pressed against each other with the rule ^¬ Between the seats arranged foil 23rd As a result, the film 23 is pressed against the seal 26, whereby in the recess 24, a sealed cavity is formed. Via the channel 27, a large negative pressure is generated in the cavity formed in the recess 24, so that there is a technical vacuum exists. In the same way, a large negative pressure between the second mold half 22 and the film 23 is created via the second channel 31, whereby in the macrostructure 28 formed by a recess also a technical vacuum is present. The first mold half 21 and the second mold half 22 are heated, whereby the film 23 is heated.

Fig. 8 shows a third step of the preferred embodiment of the method according to the invention. By heating the first mold half 21 and the second mold half 22 has the

Film 23 reaches a temperature which is above the glass transition temperature of the polycarbonate ^¬ of about 160 ° C. The film 23 is thus converted into a flowable state. The previously existing in the cavity formed by the recess 24 technical vacuum is now degraded and instead of ^¬ a gas stream is passed through the first channel 27 into the cavity formed by the recess 24, which has a high dynamic pressure. As a result, acts on the film 23, a pressure pulse, which is maintained over a period of a few seconds. The pressure impulse causes the film 23 to be pressed in the direction of the macrostructured hollow mold 28 and in the direction of the microstructured hollow molds 29. Fig. 9 shows a fourth step of the preferred embodiment of the method according to the invention. After the introduced via the first channel 27 the gas stream has led to a pressure pulse had a period of several seconds on the film 23, the film was completely formed by the makrostruktu ^¬ tured cavity mold 28 and through the micro-structured hollow molds 29 23rd The film 23 has now completely adopted the shape of the second mold half 22.

After the film 23 has been completely formed, the first mold half 21 and the second mold half 22 are cooled, for example by no further heat being supplied. The first mold half 21 and the second mold half 22 may be exposed to ambient temperature or to a coolant for the purpose of cooling.

10 shows a fifth step of the preferred embodiment of the method according to the invention. The introduced via the first channel 27 gas flow was adjusted. Via the first channel 27 and via the second channel 31 is now aeration, whereby the cooling of the first mold half 21, the second mold half 22 and the film 23rd

is accelerated.

Fig. 11 shows a sixth step of the preferred embodiment of the method according to the invention. The first mold half 21 and the second mold half 22 are separated from each other, so that the formed film 23 can be removed. The formed film 23 has now reached a temperature which is below the glass transition temperature, so that a plastic deformation of the film 23 is present. The film 23 now has a macrostructure 32 and microstructures 33.

To facilitate removal of the formed film 23, after the first mold half 21 has been removed from the second mold half 22, a slight gas pressure may be passed over the second channel 31 such that the formed film 23 is pressed away from the second mold half 22. Also, the film 23 can be clamped in a clamping frame (not shown), whereby the removal of the first mold half 21 and the second mold half 22 is simplified.

The steps of the method according ^¬ invention shown in Figures 6 to 11 may alternatively be organized in a so-called roll-to-roll operation. A film receiving roll (not shown) preferably has spacers therefor to prevent destruction of the microstructures 33 when the film 23 is rolled up. Fig. 12 shows a seventh step of the preferred embodiment of the method according to the invention. In this step, the microstructures 33 of the film 23 are exposed to heavy ion radiation 34. For this purpose, for example, a synchrotron (not shown) from which heavy ions, in particular gold ions at a defined angle to the

Microstructures 33 can be shot. The heavy ions of heavy ion radiation 34 have a discrete energy that allows them to penetrate an obstacle of discrete thickness. If the thickness of the obstacle is too large, the heavy ions will not pass through the material. The heavy ions passing through the microstructures 33 of the film 23 destroy the crystal structure of the polycarbonate on the tracks of heavy ions. Subareas of the microstructure Ren 33, which have a greater thickness, are of the

Heavy ions not penetrated.

The microstructures 33 of the film 23 are covered with a mask 36, so that the heavy ions of the heavy ion radiation 34 only reach selected subregions of the microstructures 33. The mask 36 is not absolutely necessary for the method according to the invention. Using the mask 36, the

Crater 13 (shown in Fig. 5) in the portions of the film 23, which have a greater thickness can be avoided.

Fig. 13 shows an eighth step of the preferred embodiment of the method according to the invention. The molded film 23 irradiated with heavy ions is placed in an etching bath 37. As a liquid for the etching 37 is suitable

For example, a 5 molar sodium hydroxide with 10% methanol, which was heated to a temperature of 45 ° C. An denjeni ^¬ gen areas of the film 23 that have been shot through (shown in Fig. 12) 34 of the heavy ions of heavy ion irradiation, continuous pores are formed 12 (shown in Fig. 4). The size of the pores 12 can be adjusted via the etching time.

For example, the diameter of the pores 12 is about 2 ym after an etching time of 30 minutes. Finally, the formed and etched foil 23 is made of

Remove etching bath 37 and rinse. There is now a partially perforated microstructured shaped body, which is formed by the film 23. LIST OF REFERENCE NUMBERS

01 microstructured shaped body (foil)

02 Macrostructure

03 microstructure (cavities)

04

05

06 detail

07 undeformed area

08 lower area of the cavity

09 area with minimum thickness

10

11 area with maximum thickness

12 pores

13 craters

21 first half of the mold

22 second mold half

23 foil (microstructured shaped body) 24 recess

25

26 sealing elements

27 first channel

28 macrostructured mold

29 microstructured molds

30

31 second channel

32 macrostructure

33 microstructures

34 heavy ion radiation

35

36 mask

37 etching bath

Claims

claims

1. Process for the preparation of a partially perforated

microstructured shaped body (Ol; 23) comprising the following steps:

- Providing a deformable film (Ol; 23);

- Partially stretching the film (Ol; 23), whereby

thinned draw areas (02, 03, 32, 33) of the film (01, 23) are formed and undeformed areas (07) of the film (01, 23) are preserved;

- Forming of microstructures (03, 33) in at least

some of the thinned draw areas (02, 03, 32, 33) of the film (01, 23); and

- Producing pores (12) in at least one of the thinned draw areas (03; 33) of the film (01; 23), wherein at least some of the undeformed areas (07) of the film (01; 23) remain impermeable.

2. The method according to claim 1, characterized in that generating the pores (12) in the at least one of

in that a perforation method for producing pores (12) is applied to at least some of the undeformed regions (07) and to at least some of the thinned draw regions (02; 03; 32; 33) of the film (01; 23) is applied, wherein

Parameters of the perforation method are dimensioned so that pores (12) do not arise in the undeformed areas (07).

3. The method according to claim 2, characterized in that the perforation method comprises the following substeps:

- Irradiating the some of the undeformed areas (07) and the some of the thinned drawing areas (02, 03, 32, 33) of the film (01, 23) with a

ionizing radiation (34) for generating

Iondurchschüssen in the film (01, 23), wherein the intensity of the ionizing radiation (34) is dimensioned so that only in the irradiation (34) exposed dilute stretching regions (03, 33)

Ion penetration occurs; and

- Etching the foil, resulting in the ion shots

continuous pores (12) arise.

4. The method according to claim 3, characterized in that when irradiating the film (01, 23), this is covered with a mask (36).

5. The method according to any one of claims 1 to 4, characterized

characterized in that the partial stretching and shaping of the microstructures (03; 33) are the following

Sub-steps includes:

- Using a thermoplastic as a material for the film (01, 23);

- Inserting the film (01, 23) between a first

Mold half (21) and a second mold half (22), wherein the second mold half (22) has a macrostructured

Hollow mold (28), in which microstructured molds (29) are formed;

- Sealing the first mold half (21) relative to the film (01, 23); - compressing the first mold half (21) and the second mold half (22) with the film (Ol; 23) therebetween;

- Heating the film (Ol; 23) to at least one

Glass transition temperature of the thermoplastic;

- Generating an overpressure between the first

Mold half (21) and the film (Ol; 23), whereby the film (Ol; 23) in the macrostructured mold (28) and in the microstructured molds (29) is pressed and simultaneously stretched; and

- cooling the film (01, 23).

A microstructured molding (01; 23) comprising a film (01; 23) divided into undeformed regions (07) and thinned orientation regions (02; 03; 32; 33), at least some of which are thinned

Drawing areas (03; 33), wherein pores (12) are formed in at least one of the thinned drawing areas (03; 33), and wherein at least some of the undeformed areas (07) are impermeable.

Microstructured shaped body (01; 23) according to claim 6, characterized in that the dilution in the stretching regions (02; 03; 32; 33) of the film (01; 23) begins at edges of the undeformed regions (07) until the microstructures (03 33), the pores (12) being present only in regions (08) of the thinned draw regions (03; 33) having a thickness that is less than a limit thickness.

8. Microstructured shaped body (Ol; 23) according to claim 7, characterized in that some subregions (08) of the microstructures (03; 33) have a thickness which is smaller than the limit thickness, whereby other subregions (11) of the microstructures (03 33) have a thickness which

at least as large as the limit thickness.

9. Microstructured shaped body (01; 23) according to claim 8, characterized in that subregions of the

Microstructures (03, 33), which are covered by other portions of the microstructures (03, 33) are impermeable.

10. Microstructured shaped body (01, 23) according to one of

Claims 6 to 9, characterized in that the

thinned draw regions (02, 03, 32, 33) are formed in a macrostructure (02, 32) of the film (01, 23).