DE102009044113A1 - Partially perforated microstructured molding and process for its production - Google Patents

Abstract

The present invention relates to a partially perforated microstructured shaped body (01), as it can be used for example for the cultivation of biological cells or as a sieve structure. In addition, the invention relates to a method for producing such a shaped body (01). The method according to the invention initially comprises a step in which a deformable film (01) is provided. In a further step, the film (01) is partially stretched. The result is areas of stretching (02, 03) in which the film (01) has a reduced thickness. Restricting the stretching to some areas (02, 03) of the film (01) results in that undeformed areas (07) of the film (01) are preserved. The inventive method further comprises a step in which microstructures (03) are formed in at least some of the thinned draw regions (02, 03) of the film. According to the invention, pores are produced in at least one of the thinned draw regions (03) of the film (01), while at least some of the undeformed regions (07) remain impermeable. The undeformed areas (07) of the film (01) remain impermeable because no continuous pores are produced in these areas.

Description

The present invention relates to a partially perforated microstructured shaped body, as it 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.

The DE 102 03 250 C1 shows a method and apparatus 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 simultaneously pressed against each other to impress the embossed structure in the film. The tool plate is separated after cooling again from the film.

From the DE 10 2007 050 976 A1 For example, a method of forming a film is known, in which the film to be formed is firmly joined to a mold which has at least one opening. Subsequently, portions of the film to be formed are subjected to a physical or chemical modification. The film connected to the mold backdrop is placed in a mold and pressurized with a pressure medium, which forms the film in the breakthrough of the mold scenery.

The DE 10 2004 035 267 B3 shows a microstructured molding and a process for its preparation. The molded body consists of a film, in which at least one hollow structure is introduced. The hollow structure preferably has an omega structure. The entire shaped body, ie both the foil and the hollow structures, have a multiplicity of pores whose diameter preferably assumes a value between 10 nm and 10 μm. The pores are statistically distributed over the entire molded body, ie over the film and the hollow structures, it being possible for individual pores to overlap. The 7 of the DE 10 2004 035 267 B3 clearly shows that the pores are formed both in the hollow structure and in undeformed areas 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 accurately map the areas to be provided with pores, which requires 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 molded article to be produced is partially perforated, ie only some regions of the molded article have 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 arbitrary, for example in the range between 1 .mu.m 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 will leave undeformed areas of the film intact. In these undeformed areas, the thickness of the film has not or only slightly changed. The inventive method further 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 areas of the film remain impermeable because no continuous pores are created in these areas. Preference is given to all undeformed areas of the film impermeable. Also, the pores are preferably formed in all of the thinned stretch regions of the film insofar as these regions have a thickness less than a limit thickness and insofar as these areas are not obscured 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.

The pores in the at least one of the thinned enforcement areas are preferably formed by applying a perforation method to create pores on at least some of the undeformed areas and at least some of the thinned stretch areas of the film, wherein parameters of the perforation method are measured such that pores do not arise 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. Areas of the film which have a thickness which is at least as large as the limit thickness can not be perforated by the perforation method with the selected parameters, or at least not completely pierced, so that no continuous pores are formed. 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 area 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 the film is irradiated, the film is covered with a mask in order additionally to 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. However, according to the invention, the mask is not necessary to ensure that pores do not form in the undeformed areas of the film.

The partial stretching and shaping of the microstructures in the film preferably takes place by means of a thermoplastic 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 to be sealed against the film, whereby a separate cavity 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 of the first mold half to the film and the compression of 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 is 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. In the simplest case, the macrostructured hollow mold can be cuboid-shaped, with the shaping of the parallelepiped shape serving, in particular, for the regions of the film to be deformed to pull out of the original position, whereby the areas to be deformed stretched and stretched, so it comes to a thinning. Regions of the film that are located outside the macrostructured mold are not deformed. This may be, for example, a rectangular boundary frame, which limits the cuboidal mold. In a further substep, the film is allowed to cool so that the temperature of the film falls below the glass transition temperature of the thermoplastic and the film retains its resulting shape.

The microstructured molding according to the invention initially comprises a film, from which it is completely formed 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 of which is undeformed, while a rectangular inner area is stretched and has a smaller thickness. Microstructures are formed in at least some of the thinned stretch regions. For example, the microstructures may be arranged like a matrix in the rectangular inner region of the film. Pores are formed in at least one of the thinned stretch regions. The pores are holes that 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 undeformed areas has pores, whereby the undeformed areas are all impermeable.

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 subregions of the microstructures have a thickness which is smaller than the limit thickness, while other subregions of the microstructures have a thickness which is at least as great as the limit thickness. In this embodiment of the microstructured shaped body according to the invention, the pores are only present in those partial areas of the microstructures in which they are required for the intended application.

The microstructured shaped body according to the invention is preferably designed in such a way that subregions of the microstructures which are covered by other subregions of the microstructures are impermeable since they have no pores. The formation of the microstructures leads to the different subareas of the microstructures having different orientations. Some of the subregions have an orientation perpendicular to the orientation of the entire film. From a viewing angle perpendicular to the main extension surface of the film, therefore, not all partial regions of the microstructures can be seen, since they are concealed for example because of the vertically oriented orientation or else through other partial regions of the microstructures. The hidden portions of the microstructures have no pores, which may be due to the one hand, the production and on the other hand can be used individually adapted to the intended application execution.

In a preferred embodiment of the microstructured shaped body according to the invention, the thinned drawing regions are formed within a macrostructure of the film. 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. In particular, the macrostructure can serve to divide the microstructured shaped body into an undeformed area outside the macrostructure and into a thinned drawing area 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 a preferred embodiment of a microstructured shaped body according to the invention in a sectional view;

2 : a detail of in 1 shown microstructured shaped body;

3 : a microstructure of in 1 Shaped body shown;

4 : a detail of in 3 shown microstructure with pores;

5 : a detail of in 3 shown microstructure with craters;

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

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

8th a third step of the preferred embodiment of the process according to the invention;

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

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

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

12 a seventh step of the preferred embodiment of the process of the invention; and

13 an eighth step of the preferred embodiment of the method according to the invention.

1 shows a preferred embodiment of a microstructured shaped body according to the invention 01 in a sectional view. The microstructured shaped body according to the invention 01 is formed by a film of polycarbonate. The microstructured molding 01 has a macrostructure 02 and microstructures 03 on. The individual microstructures 03 form cavities, which are arranged in a matrix. The through the microstructures 03 formed cavities serve the cultivation of biological cells. The macrostructure 02 causes the field of microstructures 03 is arranged offset. A detail marked by a circle 06 of the microstructured shaped body according to the invention 01 is in 2 shown. The microstructured molding 01 points outside the macrostructure 02 and outside the microstructures 03 an undeformed area 07 on.

2 shows the detail 06 of in 1 shown microstructured shaped body 01 , In the undeformed area 07 has the microstructured molding 01 forming film has a thickness of about 100 microns. The foil 01 is through the macrostructure 02 and through the the microstructures 03 stretched forming cavities, causing the thickness of the film 01 starting from the undeformed area 07 about the macrostructure 02 into the cavities 03 continuously decreases. In a lower area 08 the cavity shown 03 , which is marked by a hatched area for illustrative purposes, is the thickness of the film 01 only a fraction of the thickness of the film 01 in the undeformed area 07 ,

3 shows the in 2 shown microstructure 03 in a further detail view. The thickness of the film 01 Also takes inside the cavity 03 clearly off. An area marked by a circle 09 the cavity 03 is in detail in 4 shown. An area marked by a circle 11 the cavity 03 is in detail in 5 shown.

4 shows the area 09 the in 3 shown cavity 03 in detail. The foil 01 is in an area of the cavity 03 shown in section, in which the thickness of the film 01 is minimal. In this area, the film points 01 a variety of pores 12 on. The pores 12 For example, they can be used for the passage of gases or liquids. The pores 12 have a diameter of about 2 microns.

5 shows the area 11 the in 3 shown cavity 03 in detail. In that area 11 owns the foil 01 one in the cavity 03 maximum thickness. In that area 11 are craters 13 formed, which are formed by lugs of pores. Anyhow, the craters are 13 not continuous, so liquids or gases entering the craters 13 enter, not through the foil 01 can reach.

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 method according to the invention, a first mold half 21 and a second mold half 22 as well as a deformable foil 23 provided. The first half of the mold 21 and the second half of the mold 22 consist of a solid temperature resistant material, such as glass or metal. The first half of the mold 21 points opposite the foil 23 a recess 24 on to a cavity between the film 23 and the first half of the mold 21 to be able to create. This through the recess 24 formed cavity can by means of sealing elements 26 opposite the foil 23 be sealed. In the first half of the mold 21 is a first channel 27 formed, which from the outer of the first mold half 21 to the recess 24 leads. The second half of the mold 22 has a macrostructured hollow shape formed by a recess 28 on. The macrostructured mold 28 has essentially the shape of a flat cuboid. Inside the macrostructured mold 28 , Namely, in a base of the cuboid shape of the macrostructured mold 28 are microstructured molds 29 educated. The macrostructured mold 28 and the microstructured molds 29 form a negative mold of the microstructured molding to be produced. In the microstructured molds 29 are wells with a diameter of about 300 microns. Typical microstructures have dimensions in the range of a few microns to a few mm. In the second half of the mold 22 is a second channel 31 formed, which from the outer of the second mold half 22 to one with the foil 23 in contact area of the second mold half 22 leads.

The foil 23 consists of polycarbonate. As material for the film 23 Other thermoplastic polymers are also suitable.

7 shows a second step of the preferred embodiment of the method according to the invention. The first half of the mold 21 and the second half of the mold 22 be with the interposed foil 23 pressed against each other. This will cause the film 23 against the seal 26 pressed, causing in the recess 24 a sealed cavity has arisen. About the channel 27 There is a large negative pressure in the recess 24 formed cavity, so there is a technical vacuum exists. In the same way is over the second channel 31 a large negative pressure between the second half of the mold 22 and the foil 23 created, whereby in the macrostructure formed by a recess 28 There is also a technical vacuum.

The first half of the mold 21 and the second half of the mold 22 are heated, which also causes the film 23 is heated.

8th shows a third step of the preferred embodiment of the method according to the invention. By heating the first half of the mold 21 and the second mold half 22 has the foil 23 reaches a temperature which is above the glass transition temperature of the polycarbonate of about 160 ° C. The foil 23 is thus converted into a flowable state. The previously in the through the recess 24 formed cavity existing technical vacuum is now mined and instead is through the first channel 27 a gas flow in through the recess 24 formed cavity which has a high dynamic pressure. This affects the film 23 a pressure pulse, which is maintained over a period of a few seconds. The pressure pulse causes the film 23 in the direction of the macrostructured mold 28 and in the direction of the microstructured molds 29 is pressed.

9 shows a fourth step of the preferred embodiment of the method according to the invention. After the over the first channel 27 Initiated gas flow has led to a pressure pulse over several seconds on the film 23 worked, became the slide 23 completely through the macrostructured mold 28 and through the microstructured molds 29 formed. The foil 23 now has completely the shape of the second mold half 22 accepted.

After the slide 23 has been fully formed, the first half of the mold 21 and the second half of the mold 22 cooled, for example, by the fact that no further heat is supplied. The first half of the mold 21 and the second half of the mold 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 over the first channel 27 introduced gas flow was discontinued. About the first channel 27 and over the second channel 31 now takes place aeration, whereby the cooling of the first mold half 21 , the second half of the mold 22 and the foil 23 is accelerated.

11 shows a sixth step of the preferred embodiment of the method according to the invention. The first half of the mold 21 and the second half of the mold 22 are separated so that the formed film 23 can be removed. The formed foil 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 foil 23 now has a macrostructure 32 and microstructures 33 on.

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

The in the 6 to 11 shown steps of the inventive method can alternatively be organized in a so-called roll-to-roll operation. One the slide 23 receiving roll (not shown) preferably has spacers for this, in order to destroy the microstructures 33 to prevent if the film 23 being rolled up.

12 shows a seventh step of the preferred embodiment of the method according to the invention. At this step, the microstructures become 33 the foil 23 a heavy ion radiation 34 exposed. For this purpose, for example, a synchrotron (not shown) is suitable, 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 with a discrete thickness. If the thickness of the obstacle is too large, the heavy ions will not pass through the material. The through the microstructures 33 the foil 23 passing heavy ions destroy the crystal structure of the polycarbonate on the tracks of heavy ions. Subareas of microstructures 33 , which have a greater thickness, are not penetrated by the heavy ions.

The microstructures 33 the foil 23 are with a mask 36 covered so that the heavy ions of heavy ion radiation 34 only selected parts of the microstructures 33 to reach. The mask 36 is not absolutely necessary for the process according to the invention. Using the mask 36 can the craters 13 (shown in 5 ) in the subregions of the film 23 , which have a greater thickness, can be avoided.

13 shows an eighth step of the preferred embodiment of the method according to the invention. The shaped foil irradiated with heavy ions 23 gets into an etching bath 37 placed. As a liquid for the etching bath 37 For example, a 5 molar sodium hydroxide with 10% methanol, which was heated to a temperature of 45 ° C is suitable. At those points of the film 23 caused by heavy ions of heavy ion radiation 34 (shown in 12 ) were shot through, continuous pores are formed 12 (shown in 4 ). The size of the pores 12 can be adjusted via the etching time. For example, the diameter of the pores is 12 approx. 2 μm after an etching time of 30 minutes.

Finally, the formed and etched foil 23 from the etching bath 37 take out and rinse. There is now a partially perforated microstructured shaped body, which passes through the film 23 is formed.

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 of maximum thickness

12

pore

13

crater

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

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10203250 C1 [0002]
• DE 102007050976 A1 [0003]
• DE 102004035267 B3 [0004, 0004]

Claims (10)

Process for producing a partially perforated microstructured shaped body ( 01 ; 23 ), comprising the following steps: providing a deformable film ( 01 ; 23 ); Partial stretching of the film ( 01 ; 23 ), whereby thinned draw areas ( 02 ; 03 ; 32 ; 33 ) of the film ( 01 ; 23 ) and undeformed areas ( 07 ) of the film ( 01 ; 23 ) remain; - forming microstructures ( 03 ; 33 ) in at least some of the thinned stretch regions ( 02 ; 03 ; 32 ; 33 ) of the film ( 01 ; 23 ); and - generating pores ( 12 ) in at least one of the thinned stretch regions ( 03 ; 33 ) of the film ( 01 ; 23 ), wherein at least some of the undeformed areas ( 07 ) of the film ( 01 ; 23 ) remain impermeable. Method according to claim 1, characterized in that the production of the pores ( 12 ) in the at least one of the thinned drawing regions ( 03 ; 33 ) in that a perforation process for producing pores ( 12 ) on at least some of the undeformed areas ( 07 ) and at least some of the thinned draw areas ( 02 ; 03 ; 32 ; 33 ) of the film ( 01 ; 23 ), wherein parameters of the perforation method are dimensioned such that pores ( 12 ) in the undeformed areas ( 07 ) do not arise. A method according to claim 2, characterized in that the perforation method comprises the following sub-steps: irradiation of some of the undeformed regions ( 07 ) and some of the diluted stretch regions ( 02 ; 03 ; 32 ; 33 ) of the film ( 01 ; 23 ) with ionizing radiation ( 34 ) for generating ion permeations in the film ( 01 ; 23 ), whereby the intensity of the ionizing radiation ( 34 ) is dimensioned so that only in the irradiation ( 34 ) exposed dilute draw areas ( 03 ; 33 ) Ion shots occur; and - etching the foil, whereby through the ion passages continuous pores ( 12 ) arise. A method according to claim 3, characterized in that when irradiating the film ( 01 ; 23 ) with a mask ( 36 ) is covered. Method according to one of claims 1 to 4, characterized in that the partial stretching and shaping of the microstructures ( 03 ; 33 ) comprises the following sub-steps: - using a thermoplastic as material for the film ( 01 ; 23 ); - insert the foil ( 01 ; 23 ) between a first mold half ( 21 ) and a second mold half ( 22 ), the second half ( 22 ) a macrostructured mold ( 28 ), in which microstructured molds ( 29 ) are formed; - sealing the first mold half ( 21 ) opposite the foil ( 01 ; 23 ); - compressing the first half of the mold ( 21 ) and the second half of the mold ( 22 ) with the film in between ( 01 ; 23 ); Heating the film ( 01 ; 23 ) to at least a glass transition temperature of the thermoplastic; Generating an overpressure between the first half of the mold ( 21 ) and the film ( 01 ; 23 ), whereby the film ( 01 ; 23 ) into the macrostructured mold ( 28 ) and in the microstructured molds ( 29 ) is pressed and simultaneously stretched; and - cooling the film ( 01 ; 23 ). Microstructured shaped body ( 01 ; 23 ) comprising a film ( 01 ; 23 ) in undeformed areas ( 07 ) and thinned draw areas ( 02 ; 03 ; 32 ; 33 ), wherein at least in some of the thinned stretch regions ( 03 ; 33 ) Microstructures ( 03 ; 33 ) are formed, wherein pores ( 12 ) at least in one of the dilute drawing regions ( 03 ; 33 ) are formed, 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 drawing areas ( 02 ; 03 ; 32 ; 33 ) of the film ( 01 ; 23 ) starting at edges of the undeformed areas ( 07 ) down to the microstructures ( 03 ; 33 ) is increasingly formed, the pores ( 12 ) only in regions ( 08 ) of the thinned draw areas ( 03 ; 33 ) having a thickness smaller than a limit thickness. Microstructured shaped body ( 01 ; 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 is at least as large as the limit thickness. Microstructured shaped body ( 01 ; 23 ) according to claim 8, characterized in that subregions of the microstructures ( 03 ; 33 ) caused by other parts of the microstructures ( 03 ; 33 ) are impermeable. Microstructured shaped body ( 01 ; 23 ) according to one of claims 6 to 9, characterized in that the thinned draw areas ( 02 ; 03 ; 32 ; 33 ) in a macrostructure ( 02 ; 32 ) of the film ( 01 ; 23 ) are formed.

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