Method for producing undercut shaped bodies by thermoforming

Abstract

The present invention relates to a method for producing undercut shaped bodies by thermoforming, wherein the method comprises the following steps: - providing a film of thermoplastic material; - heating the film to a temperature at which the film can be plastically deformed; - feeding the film between a lower die and an upper die, which can be moved relative to one another in an axial direction perpendicular to the film, wherein the lower die comprises a plurality of mould segments, each of which has a moulding surface complementary to the undercut shaped body; - closing the lower die and the upper die while a differential pressure is applied to the film in order to shape the film to form the shaped bodies on the moulding surface of the mould segments; - separating the individual shaped bodies from the film; - opening the lower die and the upper die; and - removing the undercut shaped bodies from the mould segments by means of gripping elements, each of which forms a form-locking and / or frictional connection with a shaped body.

Description

[0001] A 501 245 p

[0002] September 9, 2025

[0003] P

[0004] Method for producing undercut shaped bodies by thermoforming

[0005] The present invention relates to a method for producing undercut shaped bodies by thermoforming.

[0006] The invention further relates to a device for producing undercut shaped bodies by means of thermoforming.

[0007] Thermoforming is a long-established process for manufacturing shaped parts from thermoplastic materials. However, in its basic form, it is only suitable for producing relatively simple shaped parts that do not have pronounced undercuts, so that the parts can be easily removed from a positive or negative mold segment after forming.

[0008] However, there is a growing interest in manufacturing more complex molded parts using thermoforming, particularly threaded parts such as closures for containers or similar items. These undercut molded parts are currently mostly produced using injection molding, which, however, requires more material because the wall thickness cannot be reduced as much as with a thermoformed part.

[0009] When thermoforming undercut molded parts, the challenge lies in removing the parts from the mold segments without damage. For parts with threads (e.g., screw caps), one option is to unscrew the mold segments from the molded parts after forming. However, this requires significant technical effort because several rotatable mold segments, typically A 501 245 p, are involved.

[0010] September 9, 2025 P

[0011] - 2 - simultaneously provide cooling and must be arranged within a tool.

[0012] The invention is therefore based on the objective of proposing an improved method and an improved device for the production of undercut molded bodies.

[0013] This problem is solved in the inventive method by comprising the following steps:

[0014] - Providing a film made of a thermoplastic material;

[0015] - Heating the film to a temperature at which the film is plastically deformable;

[0016] - Feeding the foil between a lower tool and an upper tool, which are movable relative to each other in an axial direction perpendicular to the foil, wherein the lower tool comprises a plurality of form segments, each of which has a molding surface complementary to the undercut form body;

[0017] - Closing of the lower and upper tools while the film is subjected to differential pressure in order to reshape the film on the molding surface of the mold segments, forming the molded bodies;

[0018] - Separating the individual molded parts from the foil;

[0019] - Opening the lower tool and upper tool; and

[0020] - Removal of the undercut molded bodies from the mold segments by gripping elements, each of which forms a positive fit and / or force fit with a molded body.

[0021] In the inventive method, the formed undercut molded bodies are first separated from the film before being removed from the mold segments. This allows the molded bodies to be removed individually and independently of each other from the mold segment. According to the invention, this is achieved with the aid of gripping elements, the specific functional mode of which is described in A 501 245 p

[0022] September 9, 2025 P

[0023] - 3 - it can be flexibly adapted to the geometry of the molded parts or undercuts. This will be discussed in detail below.

[0024] In this description, the terms "lower tool" and "upper tool" are used solely to functionally distinguish the two tool halves. That is, the lower tool, unlike the upper tool, comprises the forming segments on which the molded parts are formed. This makes no statement about the orientation of the two tool halves in space; the lower tool can also be positioned "on top." Likewise, the two tool halves can, for example, be arranged horizontally side by side.

[0025] When the present description refers to closing or opening "the lower tool and upper tool", this basically means a relative movement of the lower tool and upper tool away from each other or towards each other, regardless of whether both tool halves move or only one.

[0026] The separation process itself is preferably carried out by punching out the individual shapes from the film, preferably during or immediately after the closing of the lower and upper tools. For this purpose, appropriate blades are integrated into the lower or upper tool, which perform the punching process during closing. The punching can be done by means of a shear cut or a knife cut.

[0027] In a preferred embodiment of the invention, the undercut shaped bodies have a thread at least in sections. The axis of rotation of the thread is preferably parallel to the axial direction and perpendicular to the film plane.

[0028] Various types of undercut shaped bodies with a thread can be produced using the method according to the invention. The undercut shaped bodies can preferably be closure elements, A 501 245 p

[0029] September 9, 2025 P

[0030] - 4 - in particular screw caps for various types of containers, e.g. for PET bottles. The closure elements advantageously have a lid wall and a side wall which define an interior of the closure element, the side wall having at least a section with an internal thread and a corresponding external thread.

[0031] Such locking elements can be manufactured using positive mold segments whose impression surfaces have an external thread complementary to the internal thread of the locking element, or using negative mold segments whose impression surfaces have an internal thread complementary to the external thread of the locking element. Positive mold segments are preferred because they allow the internal thread of the locking element to be produced with high molding accuracy.

[0032] The gripping elements provided in the inventive method engage with the molded parts in a positive and / or force-fit manner. For this purpose, the gripping elements are adapted to the geometry of the molded parts. In the simplest case, the positive and / or force-fit is achieved by pressing the gripping element onto the molded part (in the case of positive mold segments) or by pressing the gripping element into the molded part (in the case of negative mold segments). Alternatively, the gripping elements can, for example, also have movable gripping arms.

[0033] The gripping elements are preferably arranged on a removal device. The arrangement of the gripping elements on the removal device corresponds to the arrangement of the mold segments in the lower tool, so that after the mold segments have been cut out, they can be removed synchronously and automatically from the mold segments using the removal device.

[0034] The removal device and the thermoforming tool (with the lower and upper tools) can be arranged and interact in various ways. A 501 245 p

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[0037] In a preferred embodiment of the method, after the lower and upper tools have been opened, the removal device is moved into a removal position between the lower and upper tools, and after the molded parts have been removed, it is moved out of the removal position. The direction of movement of the removal device is preferably perpendicular to the axial direction. In the removal position, the gripping elements move axially towards the molded parts, engage in a positive and / or force-fit, and remove the molded parts axially. For this to occur, the lower and upper tools must open wide enough to provide sufficient space for the removal device.

[0038] In a further preferred embodiment, after opening the lower and upper tools, the lower tool is tilted from the axial direction, preferably by approximately 70° to approximately 90°, whereby the removal device and / or the gripping elements then move towards the lower tool to remove the molded parts from the mold segments. Due to the tilting of the lower tool, it is sufficient if the removal device or the gripping elements are only movable along one spatial direction.

[0039] It is further preferred if, after the removal of the molded parts, the removal device is tilted so that the gripping elements are oriented downwards in order to be able to place the molded parts, preferably onto a conveyor device.

[0040] Removing the individual molded parts from the mold segments can be achieved in various ways, particularly depending on the undercut geometry. If the undercut is shallow, the molded parts can be removed from the mold segments, especially by means of forced demolding, in which the molded part is elastically deformed. For a molded part with a thread, forced demolding is generally possible with threads having a large flank angle. The extent of elastic deformation, without causing A 501 245 p

[0041] September 9, 2025 P

[0042] - 6 - whether damage to the molded body occurs also depends on the thickness of the film and the type of thermoplastic material.

[0043] In a further embodiment of the invention, the mold segments are negative mold segments and each consists of two or more sub-segments that move radially outwards after the lower and upper tools have been opened, in order to remove the molded parts. This requires a more complex design of the lower tool with divisible and movable mold segments, but enables the production of molded parts even with pronounced undercuts, such as threads with small flank angles.

[0044] In a corresponding embodiment of the invention with positive mold segments, these are designed as folding cores with several sub-segments which move radially inwards after the lower and upper molds have been opened in order to remove the molded parts. Molded parts with pronounced undercuts can also be produced in this case.

[0045] In both forced demolding and the use of divisible negative mold segments or positive folding cores, it is sufficient for the removal of the molded bodies if the individual gripping elements are movable in the axial direction of the molded bodies or mold segments.

[0046] According to a further preferred embodiment of the invention, in which the molded parts have a thread at least partially, the molded parts are removed by gripping elements that unscrew a molded part from a positive mold segment or unscrew it from a negative mold segment. In this case, the undercut molded parts can be, in particular, closure elements such as screw caps. A 501 245 p

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[0049] In this embodiment, the gripping elements for removing the molded parts can be set in rotation by one or more drive units, preferably synchronously. Advantageously, electric, pneumatic, or hydraulic drive units can be used for this purpose.

[0050] The individual gripping elements can be driven by the drive unit(s) via gears, belts, or chains. The drive unit(s) and the drive mechanism of the gripping elements are advantageously part of a removal device. The basic interaction of such a removal device with the thermoforming tool has already been described above.

[0051] The drive system for rotating gripping elements is generally less complex than that for rotating forming segments, as the latter typically require active cooling and must also ensure a tight seal between the film and the lower tool during forming. For this reason, rotating gripping elements (and consequently the forming segments) can typically be positioned closer together than rotating forming segments, resulting in a lower percentage of residual film (e.g., less than 25%) and higher production throughput.

[0052] During the closing of the lower and upper dies, the film is subjected to differential pressure to deform it on the forming surface of the die segments, thus creating the molded parts. This differential pressure does not necessarily have to be applied during the entire axial movement of the two die halves, but at least during one final phase of the closing movement. To generate the differential pressure, the film is subjected to positive pressure from the upper die and / or negative pressure from the lower die. It is advantageous to apply both positive and negative pressure. A 501 245 p

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[0055] When using positive forming segments, it is preferred that the upper tool has one or more cavities into which the forming segments can immerse when the lower and upper tools are closed. This can be either one large cavity into which all forming segments of the lower tool immerse, or one cavity for each individual forming segment. Preferably, the one or more cavities are pressurized during closing. After the two tool halves are closed, the areas of the upper tool located between the cavities preferably seal against the film, i.e., against the unformed areas of the film.

[0056] When using negative forming segments, the upper tool usually only has a flat contact surface which, after the two tool halves are closed, seals against the film, i.e., against the unformed areas of the film.

[0057] To apply the pressure differential to the film, the impression surfaces of the mold segments preferably have bores that are subjected to a vacuum during the closing of the lower and upper tools. The bores advantageously have a diameter of approximately 0.2 to approximately 0.8 mm. When manufacturing closure elements, the bores are preferably arranged in the area of ​​the impression surface of the mold segments where the lid wall of the closure element is formed.

[0058] It is preferred that the forming segments within the lower tool are arranged in one or more rows, each with two or more forming segments, preferably offset from one another. As mentioned above, the most compact possible arrangement of several forming segments allows the production of formed parts from a given section of film with a low amount of residual material, preferably less than 25% residual film. In the case of rotating gripping elements, their corresponding arrangement in rows also enables an effective drive mechanism for synchronized rotation. A 501 245 p

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[0060] - 9 -

[0061] In the method according to the invention, the previously heated film is typically cooled during or after the closing of the lower and upper tools, preferably by means of active cooling. It is particularly effective if the active cooling includes cooling of the mold segments by passing a cooling medium through the interior of the mold segments.

[0062] In a preferred embodiment of the invention, in which the undercut shaped bodies are closure elements with a thread, the separation from the film is carried out in such a way that the separated closure element comprises one or more film sections that protrude substantially perpendicularly outwards from a side wall of the closure element.

[0063] The film sections, which project essentially vertically outwards, are preferably designed as folding flaps distributed at equal intervals around the entire circumference of the side wall. In this embodiment of the invention, it is advantageous if the method further comprises the step of:

[0064] - Folding, bending or folding over the tabs into the interior of the closure element to provide tamper protection for the closure element.

[0065] The procedure preferably also includes the following step:

[0066] - Creating a weakening line along a circumference of the side wall below the thread of the locking element, this step being carried out, if necessary, before folding, bending, or creasing any tabs into the interior of the locking element. A 501 245 p

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[0068] - 10 -

[0069] The execution of the two aforementioned process steps enables the production of screw caps that are particularly suitable for the tamper-evident closure of beverage bottles: When the bottle is closed, the folding tabs located inside the closure element are drawn under an annular projection of the bottle neck. When the bottle is opened, the folding tabs act like a barb, causing the side wall to tear along the weakening line, and only the part of the closure element located above this line is unscrewed.

[0070] In a further advantageous embodiment of the invention, the method further comprises the step of:

[0071] - Creating an embossed structure on an outside of the side wall of the closure element in a section with the thread and / or in a downwardly adjoining section without threads.

[0072] Preferably, the embossed structure comprises axially extending grooves, which are distributed at equal intervals along the entire circumference of the side wall. Alternatively, the grooves can also be arranged only in segments. The embossed or grooved structure serves to improve the grip of the screw cap when opening and closing the container.

[0073] The embossed structure is preferably produced using an embossing tool that acts axially from above or radially from the outside on the side wall. As already mentioned, the embossed structure can be produced in the threaded section and / or in a subsequent unthreaded section. In the former case, the embossed structure is produced, in particular, on the tooth flanks of the external thread of the locking element. The outer diameter of this external thread advantageously corresponds approximately to the diameter of the locking element in the unthreaded section.

[0074] In principle, any thermoplastic material suitable for thermoforming can be used as the thermoplastic material for the film within the scope of the invention. A 501 245 p

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[0076] - 11 -

[0077] Preferred thermoplastic polymers are selected from polyesters (such as PET), polyolefins (such as PE), and other chain polymers (such as PS). Particularly preferred is a thermoplastic material selected from polyethylene terephthalate (PET), polyethylene furanoate (PEF), polybutylene terephthalate (PBT), polycarbonate (PC), polyolefins, especially polyethylene (PE) and polypropylene (PP), polystyrene (PS), styrene-acrylonitrile copolymers (SAN), acrylonitrile-butadiene-styrene copolymers (ABS), thermoplastic elastomers (TPE), especially TPE-O, TPEU, and TPE-S, ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVOH), and their copolymers and mixtures.

[0078] In the case of molded parts that serve as closure elements, these are preferably manufactured from the same material as the container to be closed. This offers a significant advantage in the recycling of the containers, as it eliminates the need for the complex separation of the materials of the screw caps and the containers. Thus, the inventive method is particularly suitable for the production of PET screw caps for closing PET beverage bottles.

[0079] Depending on the type and size of the undercut shape, the film can have a thickness in the range of approximately 0.1 to approximately 2.0 mm, preferably from approximately 0.2 to approximately 1.4 mm, more preferably from approximately 0.3 to approximately 0.9 mm, and most preferably from approximately 0.4 to approximately 0.6 mm. Starting materials with a thickness of approximately 1.5 mm or more are sometimes also referred to as "sheets"; however, in the context of this description, the term "film" is used for all materials regardless of their thickness.

[0080] The dimensions of the undercut molded body can be varied over a wide range in the inventive method. In the case of screw caps for beverage bottles, these typically have a lid wall diameter of approximately 2 to 3 cm and a side wall height of approximately 1 to 2 cm. However, the method is equally suitable for the production of screw caps for other types of A 501 245 p

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[0082] - 12 -

[0083] Containers, such as cans or buckets, even with significantly larger dimensions, as well as for the production of any other undercut shaped bodies.

[0084] The underlying problem is solved in the device according to the invention by the fact that the device comprises:

[0085] - a heating device for heating a film to a temperature at which the film is plastically deformable;

[0086] - a thermoforming tool comprising a lower tool and an upper tool which are movable relative to each other in an axial direction perpendicular to the film, wherein the lower tool comprises a plurality of forming segments, each of which has a forming surface complementary to the undercut forming body;

[0087] - Separating devices for removing the individual molded parts from the film; and

[0088] - a plurality of gripping elements, each of which can form a positive and / or force-fit connection with a molded body, for removing the molded bodies from the molded segments.

[0089] In a preferred embodiment, the device comprises a removal device on which the gripping elements are arranged.

[0090] It is particularly advantageous if the gripping elements for removing the molded parts from the mold segments can be rotated, preferably synchronously. With such a device, molded parts with a thread (e.g., closure elements) can be removed from the mold segments, as described above in connection with the method according to the invention.

[0091] Further advantages and preferred embodiments of the device according to the invention have also already been described in connection with the method according to the invention. A 501 245 p

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[0094] The device according to the invention is particularly suitable for carrying out the method according to the invention.

[0095] The embodiment described below serves to further explain the invention without limiting it in any way.

[0096] Figures 1 to 3 schematically show an embodiment of a device 10 according to the invention for producing undercut shaped bodies by thermoforming, in various stages during the execution of the method according to the invention.

[0097] The device 10 comprises a heating unit 12, a thermoforming tool 14 with a lower tool 16 and an upper tool 18, which are movable relative to each other in an axial direction 20. The lower tool 16 comprises a plurality of mold segments 22 (in this case positive mold segments) with a forming surface that is complementary to the manufactured molded bodies 24. The mold segments 22 are preferably arranged in staggered rows with the smallest possible spacing in order to produce the molded bodies 24 with the smallest possible residual material (preferably less than 25%).

[0098] The device further comprises a removal device 26 with a plurality of gripping elements 28 which can form a positive and / or force-fit connection with the manufactured shaped bodies 24.

[0099] In carrying out the method according to the invention, a film 30 made of a thermoplastic material (e.g., PET) is inserted into the open thermoforming tool 14 in a direction 32 perpendicular to the axial direction 20, after it has been heated in the heating device 12 to a temperature at which it is plastically deformable (Fig. 1). The lower tool 16 and the upper tool 18 close in the axial direction 20 to form the film 30 onto the impression surfaces of the mold segments 22, forming the molded parts 24.

[0100] September 9, 2025 P

[0101] - 14 - to be formed (not shown in the figure). During or immediately after forming, the formed bodies 24 are separated from the film 30 by separating devices integrated into the thermoforming tool 14, in particular by punching (not shown in the figure).

[0102] The mold segments 22 have a geometry to enable the production of undercut molded bodies 24 according to the invention. In particular, the mold segments 22 can have an external thread to produce molded bodies 24 that have at least a section with an internal thread (as well as a corresponding external thread), such as closure elements (e.g., screw caps).

[0103] The mold segments 22 preferably have active cooling, in particular in the form of cooling channels, to cool the molded bodies 24 after forming.

[0104] In order to remove the cooled molded parts 24 from the mold segments 22 by the gripping elements 28, the lower tool is tilted 90° from the axial direction about a tilting axis 34 in the present embodiment (Fig. 2). The removal device 26 then moves towards the lower tool 16 in the direction 32 of the film plane until the gripping elements 28 engage the molded parts 24 by positive and / or frictional engagement. As the removal device 26 moves back, the molded parts 24 are removed from the mold segments 22.

[0105] To enable the removal of the molded parts 24 from the mold segments 22, the mold segments 22 can, depending on the type of undercut, be designed as folding cores, for example, to "release" the molded parts between the forward and backward movement of the removal device 26. Removal by means of forced demolding is also possible if the geometry of the undercut allows for a corresponding elastic deformation of the molded part 22. A 501 245 p

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[0107] - 15 -

[0108] If the molded parts 24 have a thread, they can preferably be unscrewed from the molded segments 22. For this purpose, the gripping elements 28 are set into a rotational movement after the formation of the positive and / or force-fit, preferably by one or more drive devices arranged in the removal device 26 (not shown in the figure).

[0109] In the present embodiment, the removal device 26 is tilted by 90° after the removal of the molded parts 24, so that the gripping elements with the molded parts 24 are oriented downwards. In this way, the molded parts 24 can be placed by the gripping elements 26, e.g. onto a conveyor 36 (Fig. 3).

[0110] After the removal of the molded parts 24, the lower tool 16 returns to its original orientation as shown in Fig. 1, in order to be able to produce further molded parts from the next section of the film 30 in a continuous process.

[0111] Instead of tilting the lower tool 16 (according to Fig. 2) and the removal device 26 (according to Fig. 3) in the illustrated embodiment, it is alternatively possible for the removal device 26 to be moved between the lower tool 16 and the upper tool 18 in direction 32 of the film plane after the forming and separation of the molded parts 24, to remove the molded parts 24 from the mold segments 22, and then to be moved out of the thermoforming tool 14 again to place the molded parts 22 onto the conveyor 36. A 501 245 p

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[0114] Reference symbol list

[0115] 10 Device for producing undercut shaped bodies

[0116] 12 Heating system

[0117] 14 Thermoforming tool

[0118] 16 lower tools

[0119] 18 Upper tool

[0120] 20 Axial direction

[0121] 22 mold segments

[0122] 24 Shape bodies

[0123] 26 Extraction device

[0124] 28 gripping elements

[0125] 30 slides

[0126] 32 Direction of the film plane

[0127] 34 tipping axle

[0128] 36 Funding facility

Claims

A 501 245 p September 9, 2025 P - 17 - Patent claims 1. A method for producing undercut shaped bodies by thermoforming, the method comprising the following steps: - Providing a film made of a thermoplastic material; - Heating the film to a temperature at which the film is plastically deformable; - Feeding the foil between a lower tool and an upper tool, which are movable relative to each other in an axial direction perpendicular to the foil, wherein the lower tool comprises a plurality of form segments, each of which has a molding surface complementary to the undercut form body; - Closing of the lower and upper tools while the film is subjected to differential pressure in order to reshape the film on the molding surface of the mold segments, forming the molded bodies; - Separating the individual molded parts from the foil; - Opening the lower tool and upper tool; and - Removal of the undercut molded bodies from the mold segments by gripping elements, each of which forms a positive fit and / or force fit with a molded body.

2. The method according to claim 1, wherein the undercut shaped bodies have a thread at least section by section.

3. Method according to claim 2, wherein the undercut shaped bodies are closure elements, in particular screw closures, with a lid wall and a side wall that define an interior of the closure element, wherein the side wall has at least sectionally an internal thread and a corresponding external thread. A 501 245 p September 9, 2025 P - 18 - 4. Method according to claim 3, wherein the impression surfaces of the mold segments have an external thread complementary to the internal thread of the closure element or an internal thread complementary to the external thread of the closure element.

5. Method according to one of the preceding claims, wherein the gripping elements are arranged on a removal device.

6. Method according to claim 5, wherein the removal device is moved into a removal position between the lower tool and the upper tool after the lower tool and upper tool have been opened, and is moved out of the removal position after the molded parts have been removed, preferably in a direction of movement perpendicular to the axial direction.

7. Method according to claim 6, wherein after opening the lower tool and upper tool the lower tool is tilted from the axial direction, preferably by about 70° to about 90°, wherein the removal device and / or the gripping elements then move towards the lower tool in order to remove the molded parts from the mold segments.

8. Method according to one of claims 5 to 7, wherein the removal device is tilted after the removal of the molded parts so that the gripping elements are oriented downwards in order to be able to place the molded parts, preferably onto a conveying device.

9. Method according to one of the preceding claims, wherein the removal of the molded bodies from the mold segments is carried out by means of a forced demolding process in which the molded body is elastically deformed.

10. Method according to any one of claims 1 to 8, wherein the mold segments are negative mold segments and each consists of two or more A 501 245 p September 9, 2025 P - 19 - Sub-segments exist that move radially outwards after the lower and upper tools have been opened, in order to remove the molded parts.

11. Method according to any one of claims 1 to 8, wherein the form segments are positive form segments and are designed as folding cores with several sub-segments which move radially inwards after the opening of the lower tool and upper tool in order to remove the formed bodies.

12. Method according to any one of claims 1 to 8, wherein the molded parts have a thread at least sectionally, and wherein the removal of the molded parts is effected by gripping elements which each unscrew a molded part from a positive mold segment or unscrew it from a negative mold segment.

13. Method according to claim 12, wherein the gripping elements for removing the molded bodies are set in rotation by one or more drive devices, preferably synchronously.

14. Method according to one of the preceding claims, wherein the forming segments are arranged within the lower tool in one or more rows, each with two or more forming segments, which are preferably offset from one another.

15. Method according to one of the preceding claims, wherein the shaped bodies are closure elements with a thread, and wherein the separation from the film is carried out such that the separated closure element comprises one or more film sections which extend substantially perpendicularly outwards from a side wall of the closure element. A 501 245 p September 9, 2025 P - 20 - 16. Method according to claim 15, wherein the substantially perpendicular outwardly projecting film sections are designed as folding flaps distributed at equal intervals around the entire circumference of the side wall.

17. The method of claim 16, further comprising the step of: - Folding, bending or folding over the tabs into the interior of the closure element to provide tamper protection for the closure element.

18. Method according to any one of claims 15 to 17, further comprising the step: - Creating a weakening line along a circumference of the side wall below the thread of the locking element, this step being carried out, if necessary, before folding, bending or folding tabs into the interior of the locking element.

19. Method according to any one of claims 15 to 18, further comprising the step: - Creating an embossed structure on an outside of the side wall of the closure element in a section with the thread and / or in a downwardly adjoining section without threads.

20. Method according to claim 19, wherein the embossing structure comprises axially extending grooves which are preferably distributed at equal intervals along the entire circumference of the side wall.

21. Method according to claim 19 or 20, wherein the embossing structure is produced with an embossing tool which acts axially from above or radially from the outside on the side wall. A 501 245 p September 9, 2025 P - 21 - 22. A method according to any of the preceding claims, wherein the thermoplastic material is selected from polyethylene terephthalate (PET), polyethylene furanoate (PEF), polybutylene terephthalate (PBT), polycarbonate (PC), polyolefins, in particular polyethylene (PE) and polypropylene (PP), polystyrene (PS), styrene-acrylonitrile copolymers (SAN), acrylonitrile-butadiene-styrene copolymers (ABS), thermoplastic elastomers (TPE), in particular TPE-O, TPEU and TPE-S, ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVOH) and their copolymers and mixtures.

23. Method according to any of the preceding claims, wherein the film has a thickness in the range of approximately 0.1 to approximately 2.0 mm, preferably approximately 0.2 to approximately 1.4 mm, more preferably approximately 0.3 to approximately 0.9 mm, most preferably approximately 0.4 to approximately 0.6 mm.

24. Device for producing undercut shaped bodies by thermoforming, comprising: - a heating device for heating a film to a temperature at which the film is plastically deformable; - a thermoforming tool comprising a lower tool and an upper tool which are movable relative to each other in an axial direction perpendicular to the film, wherein the lower tool comprises a plurality of forming segments, each of which has a forming surface complementary to the undercut forming body; - Separating devices for removing the individual molded parts from the film; and - a plurality of gripping elements, each of which can form a positive and / or force-fit connection with a molded body, for removing the molded bodies from the molded segments.

25. Device according to claim 24, wherein the device comprises a removal device on which the gripping elements are arranged. A 501 245 p September 9, 2025 P - 22 - 26. Device according to claim 24 or 25, wherein the gripping elements for removing the mold bodies from the mold segments are rotatable, preferably synchronously. * * *

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