DE102022004776B3 - Filter element or filter for smoking devices, smoking articles and smokeless inhalers and method for producing such a filter element or filter - Google Patents

Abstract

The invention relates to a filter element, in short filters, for smoking devices, tobacco products and smokeless inhalers, in particular for tobacco and cannabis pipes as well as water pipes (shishas), cigar, cigarillo and cigarette holders. The invention also relates to a method for producing a filter element for smoking devices, tobacco products and smokeless inhalers.

Description

The invention relates to a filter element, in short filters, for smoking devices, tobacco products and smokeless inhalers, in particular for tobacco and cannabis pipes as well as water pipes (shishas), cigar, cigarillo and cigarette holders. The invention also relates to a method for producing a filter element for smoking devices, tobacco products and smokeless inhalers.

When smoking tobacco pipes, it is common to insert pre-assembled disposable filters of various designs into the smoke channel of a pipe. The filter serves two purposes: firstly, to filter out undesirable smoke contaminants and secondly, to cool the smoke. The pre-assembled filters increase the draw resistance to a greater or lesser extent, depending on the design.

For example, the patent specification DE 43 13 847 C1 A disposable smoke filter for tobacco pipes is known, which consists of a paper tube filled with a granular material and closed by end plugs with holes that allow the smoke to be filtered to pass through. With this filter, the smoke is directed onto the granular material so that it can only indirectly reach the paper tube, which therefore does not contribute particularly much to the separation of condensate. Due to the relatively few holes with small dimensions, the draw resistance of a pipe is noticeably increased by the use of such a filter. The multi-part structure of this filter also requires relatively complex production.

Smoking hand-rolled cigarettes is also possible EN 10 2020 131 196 A1 It is known to screw pre-assembled filters into the cigarette as a mouthpiece. The filter consists of a paper tube filled with a granular material, particularly activated carbon particles, and closed with end plugs with through holes, whereby the resistance to the draw is noticeably increased by the use of such a filter. The pre-assembled filter is designed as a consumable, whereby one filter is used per cigarette and must be disposed of.

The US 5 101 838 shows an article for simulating smoking by inhaling nicotine without the effect of heat, with a housing having an air inlet and an air outlet opening, which contains a support structure inside that holds a nicotine preparation that evaporates at room temperature, wherein the support structure essentially fills the effective cross-section of the housing and forms a plurality of continuous flow channels, on whose free and non-absorbent surface the nicotine preparation is deposited as a thin layer that leaves the flow channels open. However, this article is made of several parts, which requires a high manufacturing effort and is unsuitable as a filter element due to the non-absorbent surface.

From the international disclosure document WO 2021/123824 A1 A component for use in a non-flammable aerosol supply system has become known, which has an inner channel, at least one outer channel and at least one ventilation area, which are arranged so that outside air can flow into the at least one outer channel. This component for use in a non-flammable aerosol supply system is neither intended nor suitable as a filter element.

From the international disclosure document WO 2019/056029 A1 A smoking cessation attachment is known which can be applied to a peripheral surface of a smoking product, in particular a cigarette or a cigarillo, wherein the attachment comprises a bitter substance and has two openings so that the attachment can be plugged onto the smoking product. This smoking cessation attachment can particularly preferably be produced using an injection molding process and is neither intended nor suitable as a filter element.

The invention is based on the object of designing a filter element or filter for filtering, cooling and dehumidifying aerosol-containing gases, in particular smoke gases, with a comparatively low draft resistance, in which the smoke gases are brought into intensive contact with the inner walls of a smoke gas duct and can be manufactured simply and in a variable format. It is also the object of the invention to enable simple, effective cleaning for reuse of a filter. It is also the object of the invention to simplify the handling of a filter and at the same time to ensure secure fixation within a pipe, as well as to increase its value. Finally, it is the object of the invention to provide, in addition to use of the filter in smoking devices such as tobacco pipes, also use in smoking products such as hand-rolled cigarettes or cannabis joints as well as in rod-shaped smokeless inhalers, so-called "heat-not-burn products", which in the prior art are also referred to as aerosol-generating articles or HnB cigarettes for short.

This task is solved by a filter element or filter for smoking devices, smoking articles and rod-shaped smokeless inhalers, which is designed as a monolithic ceramic tubular body and has a circular cross cut on the front sides, with a first diameter on the first front side and a second diameter on the second front side, and that the filter element has at least one flue gas channel, with a front-side inlet opening and an opposite front-side outlet opening, wherein the length of the filter element is a multiple of the front-side diameters and the effective length of the flue gas channel is a multiple of the length of the filter element, and wherein the flue gas channel comprises at least three interconnected chambers one behind the other in the flow direction of the flue gas, wherein the first and the second chamber each have a cross-section in the shape of a circular ring segment and the third chamber has a circular cross-section. Furthermore, the first and the second chamber are arranged concentrically around the third chamber in a central double-walled tubular section, wherein the cross-sections in the shape of a circular ring segment of the first and the second chamber have the same radian measure < π and are arranged in their longitudinal extension between a first and a second longitudinal axial partition. The first partition wall and the second partition wall are arranged radially opposite one another between an inner tube and an outer tube, offset longitudinally and are non-detachably connected to the inner tube and the outer tube, wherein the partition walls each have a shorter length than the first and second chambers and thus, in the extension of the partition walls, a first and a second essentially tangential passage opening are formed, adjacent to the front-side outlet opening, and that the inner tube has in its tube wall, adjacent to the front-side inlet opening, an essentially radial passage opening from the second chamber into the third chamber. A main feature of the novel filter element or filter according to the invention is that the filter element or filter in the form of a partially double-walled tubular body - which has several interconnected chambers - is manufactured entirely by 3D printing, wherein in the first and/or the second chamber, at least in a central section, flow barriers, preferably in the form of truncated cones, are arranged offset between the inner tube and the outer tube.

This makes it particularly easy to further improve the filtering effect and dehumidification through a slalom-like flow pattern, while at the same time slightly increasing the draft resistance.

The 3D printing process enables the filter element according to the invention to be manufactured in one piece in a wide range of variants and formats, some with delicate structures, even in small quantities.

This particularly space-saving multi-chamber construction according to the invention, namely with a "series connection" of the chambers to form a continuous loop-shaped flue gas channel, achieves a particularly low draft resistance with good filtering effect as well as dehumidification and cooling of the flue gas.

Smoking devices within the meaning of the invention include tobacco and cannabis pipes, cigar, cigarillo and cigarette holders as well as shisha pipes and e-cigarettes.

Smoking products within the meaning of the invention include hand-rolled cigarettes, filter cigarettes, multi-filter cigarettes and cannabis joints.

Smoke-free inhalers within the meaning of the invention are primarily rod-shaped heat-not-burn products, so-called HNB cigarettes and e-cigarettes.

The terms filter element or filter are to be interpreted as equivalent; especially in the case of tobacco pipes, the state of the art also refers to filter inserts.

The design according to the invention in the form of concentrically arranged and interconnected pipes and with a continuous flue gas duct with a relatively large cross-section achieves a particularly low draft resistance. The relatively large surface of the flue gas duct also ensures an improved filter effect as well as very good dehumidification and cooling of the flue gas.

A further improvement in the filter effect is achieved by the surfaces of the filter element having pores at least in the interior of the ceramic tube body, with at least 50% of the pores having maximum dimensions between 10 µm and 100 µm. Preferably, at least 90% of the entire surface of the flue gas duct has pores of the stated size. The pores contribute to improved condensate separation and noticeably improve the dehumidification and cooling of the flue gas.

Particularly preferably, the cross-sectional areas of the first and second chambers with circular ring-shaped cross-sections have, in at least one section of the flue gas channel, essentially the same surface area as the cross-sectional area of the third chamber. This particularly simple construction ensures that the flow velocity in the smoke gas channel is largely the same. This enables effective cleaning of the pipe body or the filter element or filter using compressed air and/or a rinsing process with water or a cleaning solution.

In order to prevent the entry of foreign bodies, tobacco fibers, etc., it is provided that the front-side inlet opening comprises a grid which has at least two intersecting webs and is preferably funnel-shaped, wherein the grid extends over the entire inlet opening of the tubular body and the funnel-shaped inlet opening leads to improved flow behavior.

A further embodiment of the filter element or filter or of the tubular body according to the invention is characterized in that the flue gas channel has at least five interconnected chambers, the first, second, fourth and fifth chambers each having a circular ring-shaped cross-section with an arc measure < π, preferably < π/2, and the third chamber has a circular cross-section. This achieves a further extension of the flue gas channel, whereby the tubular body can retain its length or even be made shorter. By "connecting the five chambers in series" to form a loop-shaped flue gas channel with a relatively large cross-section, a further improved filtering effect, dehumidification and cooling of the flue gas is achieved, whereby the draft resistance is increased by approximately 50%. According to the invention, two embodiments and arrangements of the first, second, fourth and fifth chambers are provided around the third chamber. In the first arrangement, the first, second, fourth and fifth chambers lie on the same circular arc, whereby the arc measure is smaller than π/2 in each case. In the second arrangement, the fourth and fifth chambers are located concentrically around the outside of the first and second chambers, with the radian measure being greater than π/2 and less than π. Analogous to this 5-chamber design of the filter element or the tubular body, a sixth and seventh chamber can be provided, whereby the arrangement can be designed in accordance with the arrangement of the fourth and fifth chambers.

According to the invention, a cylindrical shape and a truncated cone shape are provided depending on the intended use of the filter element or filter: The cylindrical shape is characterized in that the diameter of the first end face is equal to the diameter of the second end face. The cylindrical shape is therefore particularly suitable for rod-shaped articles, such as hand-rolled cigarettes, filter cigarettes, multi-filter cigarettes or HNB cigarettes, in the latter case the filter element is integrated as a segment into the respective multi-segment filter or into the HNB cigarette. The diameters are 7 to 10 mm and are matched to the diameters of the respective rod-shaped articles. The filter element or the tubular body has a length in the range of 15 to 25 mm.

The truncated cone shape is characterized in that the diameter of the first end face is different from the diameter of the second end face, whereby the outer contour of the filter element is conical in the longitudinal direction and the cone angle α in relation to the center axis of the filter element is in the range between 0.3° and 6°, preferably between 0.5° and 3°, particularly preferably between 0.8° and 1.5°. The diameter of the first end face is approximately 7 to 15 mm, the diameter of the second end face is approximately 5 to 10 mm, with the diameters being matched to the intended smoking device, e.g. a tobacco pipe. The same applies to the length of the filter element or tubular body, which is in the range of 15 to 50 mm.

The truncated cone shape is particularly suitable for tobacco and cannabis pipes, cigar, cigarillo and cigarette holders as well as shishas (water pipes) or for conically wound smoking products such as cannabis joints. These filter elements usually have a larger diameter on the first end face with the inlet opening of the pipe body. Due to the conicity, these filters have both a sealing and a clamping or fixing function when inserted or inserted into a receiving hole in the mouthpiece of a pipe or a cigar, cigarillo or cigarette holder. The handling of the filter element when inserting or inserting is also supported by run-in bevels on both ends of the filter element.

In order to be able to prove the authenticity and/or origin of a filter element or filter, a visible and/or tangible trademark and/or a manufacturer's identification and/or an article number is incorporated into the outer wall of the outer tube of the tube body using 3D printing and/or a laser beam. This increases the value of the filter and also offers the advantage of a certain degree of protection against plagiarism.

Advantageously, in order to increase the filtering effect, the filter element or the filter also allows the inclusion of a filter plug made of synthetic or natural fibres in the front outlet opening of the flue gas duct, which at the same time is accompanied by an increase in the draught resistance.

1. a) Laden einer Basiskonfiguration des Rohrkörpers in Form eines 3-D-Schichten-Modells in die Steuerungseinheit,
2. b) Eingeben oder Laden der Länge und/oder des Durchmessers der ersten Stirnseite und des Durchmessers der zweiten Stirnseite des Rohrkörpers in die Steuerungseinheit,
3. c) Berechnen und Erstellen eines 3-D-Schichten-Modells der Endkonfiguration des Rohrkörpers und Bereitstellen von ermittelten Daten durch die Steuerungseinheit für das Antriebssystem und die Düseneinheit,
4. d) Übertragen der ermittelten Daten auf das Antriebssystem und die Düseneinheit,
5. e) Einstellen einer Basisebene für den 3-D-Druck mittels der 3-D-Druckeinrichtung,
6. f) Drucken der ersten Stirnseite in Form einer ersten kreisförmigen Schicht, die wenigstens eine eingebettete Leerfläche aufweist, gemäß eines vorbestimmten Querschnitts des zu bildenden Rohrkörpers,
7. g) Drucken einer zweiten kreisförmigen Schicht, die wenigstens eine eingebettete Leerfläche aufweist, gemäß eines vorbestimmten Querschnitts des zu bildenden Rohrkörpers,
8. h) Drucken einer weiteren kreisförmigen Schicht, die wenigstens eine eingebettete Leerfläche aufweist, gemäß eines vorbestimmten Querschnitts des zu bildenden Rohrkörpers,
9. i) Wiederholen des Schrittes h) bis zur Ebene der zweiten Stirnseite des zu bildenden Rohrkörpers,
10. j) Drucken der zweiten Stirnseite in Form einer kreisringförmigen Schicht des zu bildenden Rohrkörpers.
11. k) Bereitstellen des Rohrkörpers für eine nachgeordnete, insbesondere thermische Behandlung.

The object is also achieved by a method for producing a filter element or filter for smoking devices, tobacco products and rod-shaped smokeless inhalers, which is designed as a monolithic ceramic tubular body, wherein the method is a 3D printing method by means of a 3D printing device which comprises at least one storage for substrate particles, wherein the substrate particles are selected from the group of ceramic substrate particles, and a control unit and a nozzle unit with at least one application nozzle and/or a laser unit and/or a movable workpiece holder and a drive system for moving the at least one application nozzle and/or the laser unit and/or the movable workpiece holder, with the steps:

1. a) Loading a basic configuration of the pipe body in the form of a 3D layer model into the control unit,
2. b) entering or loading the length and/or diameter of the first end face and the diameter of the second end face of the pipe body into the control unit,
3. c) Calculating and creating a 3D layer model of the final configuration of the pipe body and providing the determined data by the control unit for the drive system and the nozzle unit,
4. d) Transferring the determined data to the drive system and the nozzle unit,
5. e) Setting a base plane for 3D printing using the 3D printing device,
6. f) printing the first end face in the form of a first circular layer having at least one embedded empty area, according to a predetermined cross-section of the tubular body to be formed,
7. g) printing a second circular layer having at least one embedded empty area according to a predetermined cross-section of the tubular body to be formed,
8. h) printing a further circular layer having at least one embedded empty area according to a predetermined cross-section of the tubular body to be formed,
9. i) repeating step h) up to the level of the second end face of the tubular body to be formed,
10. j) Printing the second end face in the form of an annular layer of the tubular body to be formed.
11. k) Providing the pipe body for subsequent treatment, in particular thermal treatment.

Loading a first configuration of the filter element or tubular body in the form of a 3D layer model and then entering or loading the length and/or diameter within predeterminable limits and then determining a second configuration, namely the target configuration of the filter element or tubular body, enables production with a large variety of shapes and formats without having to rely on a corresponding number of molds. In particular, the following should be mentioned here: Adaptation of the conicity and length for use in a filter chamber of a tobacco pipe. Adaptation of the diameter and length for use in rod-shaped products such as cigarettes, multi-segment filters and smoke-free inhalers with finely graduated diameters in the tenth of a millimeter range and with narrow length tolerances.

Last but not least, the 3D printing process provided according to the invention also makes it possible to produce small quantities of the filter or filter element cost-effectively with a wide variety of formats.

After the pipe body has been prepared for subsequent treatment, a variety of processes are known. For example, in so-called binder jetting, a binder is printed onto a layer of powder or granulate using a 3D printer and then fired and/or sintered in an oven. The binder is then thermally removed from a molded part, such as the pipe body, at a temperature between 300°C and 900°C.

There is also another 3D printing process, which is preferred here, which builds up the workpiece layer by layer with the help of a UV monomer, a liquid plastic that hardens when exposed to UV radiation. The SLA process and the DLP process are particularly noteworthy here. The SLA process uses a laser to harden the individual plastic layers and the DLP process uses a display that serves as a mask for the UV radiation. The UV monomer can also be enriched with ceramic substrate particles in order to obtain a workpiece with largely ceramic properties. These include greater strength and higher temperature resistance. The workpiece, here the tubular body according to the invention, is positioned in or on a workpiece holder, which can also be designed as a movable workpiece table.

• 1 einen Tabakpfeife im Schnitt mit einer Filterkammer und einem Filter gemäß der Erfindung;
• 2 einen vergrößerten Ausschnitt aus 1 im Bereich der Filterkammer;
• 3 eine Außenansicht eines Filterelements oder Filters gemäß der Erfindung;
• 4 eine isometrische Darstellung eines teilweise geöffneten Filters aus 3 in einer ersten Ausrichtung gemäß einer ersten Ausführungsform;
• 5 eine isometrische Darstellung eines teilweise geöffneten Filters aus 3 in einer zweiten Ausrichtung gemäß der ersten Ausführungsform;
• 6 einen Längsschnitt des Filters gemäß einer zweiten Ausführungsform;
• 7 einen Querschnitt des Filters aus 6 an der Schnittlinie A - A;
• 8 eine isometrische Darstellung eines teilweise geöffneten Filters aus 3 in einer ersten Ausrichtung gemäß einer dritten Ausführungsform;
• 9 eine isometrische Darstellung eines teilweise geöffneten Filters aus 3 in einer zweiten Ausrichtung gemäß der dritten Ausführungsform und
• 10 einen Längsschnitt des Filters aus 3 gemäß einer vierten Ausführungsform.

The invention is explained in more detail below with reference to four embodiments shown in the drawings.

• 1 a tobacco pipe in section with a filter chamber and a filter according to the invention;
• 2 an enlarged section of 1 in the area of the filter chamber;
• 3 an external view of a filter element or filter according to the invention;
• 4 an isometric view of a partially opened filter from 3 in a first orientation according to a first embodiment;
• 5 an isometric view of a partially opened filter from 3 in a second orientation according to the first embodiment;
• 6 a longitudinal section of the filter according to a second embodiment;
• 7 a cross-section of the filter 6 at the intersection line A - A;
• 8th an isometric view of a partially opened filter from 3 in a first orientation according to a third embodiment;
• 9 an isometric view of a partially opened filter from 3 in a second orientation according to the third embodiment and
• 10 a longitudinal section of the filter 3 according to a fourth embodiment.

The 1 shows a tobacco pipe 3 in a sectional view with a filter chamber 6 and a filter 1 located therein according to the invention. How to 1 As can be seen, the filter chamber 6 is positioned in the transition area between a mouthpiece 7 and a pipe bowl 9 with a smoke chamber 5 for holding tobacco. A smoke channel 5 runs straight from the mouthpiece 7 through the filter chamber 6 and the filter 1 to the smoke chamber 5. The filter chamber 6 is shown in an enlarged section in 2 and shows in detail a retaining pin 8 into which the filter 1 is inserted. In addition to the 1 and 2 In addition to the conical filters 1 shown, cylindrical filters are also known in the prior art, which can be positioned in the receiving pin 8 with some play.

The 3 shows an isometric representation of a filter or filter element 1 in the form of a tubular body 2 in a first embodiment with a cylindrical outer surface 10 and an inlet opening 12 set into the first end face 11, which comprises a grid 23 with intersecting webs 24. How to 3 , the transition from the outer surface 10 to the front side 11 is designed as a chamfer 28, which facilitates insertion into the filter chamber 6.

The 4 and 5 show isometric representations of the filter or filter element 1 of the first embodiment according to 3 , the tubular body 2 is shown partially opened to show the internal structure. In 4 the flow direction V of the flue gas is shown by an arrow which runs from left to right in the figure. In 5 the flow direction V of the flue gas is opposite and is shown by an arrow which runs from right to left in the figure. The flue gas enters the first chamber 15 through the inlet opening 12 on the first front side 11, which is in 4 is shown open. Two partition walls 18 extend from the first end face 11 and are arranged offset by 180° on the pipe wall 26 of the inner pipe 21. The partition walls 18 are shorter in their longitudinal extension than the pipe section of the inner pipe 21 between the first end face 11 and the second end face 13, whereby two essentially tangentially extending passage openings 19 to the second chamber 16 are produced on the side facing the second end face 13. As the 5 As can be further seen, a radially extending passage opening 19 from the second chamber 16 into the third chamber 17 is provided in the tube wall 26 of the inner tube 21 adjacent to the first end face 11, as is also shown in 5 is indicated by the arrow for the flow direction V of the flue gas. Finally, after flowing through the inner pipe 21, the flue gas exits the pipe body 2 and thus the filter element 1 at the outlet opening 14 on the second end face 13.

The 6 and 7 show sectional views of the filter element 1 or tubular body 2 in a second embodiment, namely in a slightly conical shape, wherein the inner chamber structure is the same as in the first embodiment according to 4 and Fig, 5. The 6 shows a longitudinal section of the filter element 1 and in the 7 a cross-section of the filter element 1 or tubular body 2 is shown. The cross-section AA shown runs approximately centrally through the tubular body 2, as the dash-dot line AA in the 6 shows. As the 6 As can be seen, the flow direction V of the flue gas runs in a loop from right to left through the flue gas channel 20, which is formed by the first chamber 15, the second chamber 16 and the third chamber 17. The flue gas enters the first chamber 15 through the inlet opening 12 on the first end face 11, then through the passage openings 19 into the second chamber 16 and through the radial passage opening 19 into the third chamber 17. Finally, the flue gas enters the third chamber 17 after flowing through the inner Pipe 21 at the outlet opening 14 on the second end face 13 from the pipe body 2 and thus from the filter element 1. The first end face 11 has in 6 a larger diameter than the second end face 13, resulting in a cone angle α on the surface line, which in the embodiment is approximately 1°.

The 8th and 9 show isometric views of a partially opened filter according to a third embodiment in a first and a second orientation. Compared to the first embodiment in 4 and 5 In the first and second chambers 15, 16, in the middle section, additional frustoconical flow barriers 25 are arranged offset between the inner tube 21 and the outer tube 22. In addition to the frustoconical flow barriers 25 shown here as examples, other shapes, such as disks with circular, teardrop-shaped or triangular cross-sections, can also be provided.

The 10 shows a longitudinal section of the filter element 1 or tubular body 2 in a fourth embodiment, namely in a slightly conical shape, wherein the inner chamber structure is the same as the third embodiment according to 8th and 9 The flue gas enters the first chamber 15 through the inlet opening 12 on the first end face 11, past the flow barriers 25 and further through the passage openings 19 into the second chamber 16, past the flow barriers 25 and through the radial passage opening 19 into the third chamber 17. Finally, after flowing through the inner tube 21, the flue gas exits the tube body 2 and thus the filter element 1 at the outlet opening 14 on the second end face 13. The first end face 11 has 10 a larger diameter than the second end face 13, resulting in a cone angle α on the surface line, which in the embodiment is approximately 1°.

List of reference symbols:

1

filter element, filter

2

Pipe body

3

Tobacco pipe

4

Smoke chamber

5

Smoke channel

6

Filter chamber

7

Mouthpiece

8th

Mounting pin

9

Pipe bowl

10

Shell surface

11

first front side

12

Entrance opening

13

second front side

14

Outlet opening

15

first chamber

16

second chamber

17

third chamber

18

partition wall

19

Passage opening

20

Flue gas duct

21

inner tube

22

outer tube

23

Grid

24

web

25

Flow barriers

26

Pipe wall

27

Pipe wall

28

Chamfer

α

Cone angle

V

Flow direction

Claims (10)

Filter element (1) for smoking devices, smoking articles and smokeless inhalers, in particular for tobacco pipes (3) and cannabis pipes as well as for shishas, cigar, cigarillo and cigarette holders, which is designed as a monolithic ceramic tubular body (2) and has a circular cross-section on the end faces (11, 13), with a first diameter on the first end face (11) and a second diameter on the second end face (13), and in that the filter element (1) has at least one smoke gas channel (20) with a front-side inlet opening (12) and an opposite front-side outlet opening (14), wherein the length of the filter element (1) is a multiple of the front-side diameters and that the effective length of the smoke gas channel (20) is a multiple of the length of the filter element (1), wherein the smoke gas channel (20) has at least three interconnected chambers (15, 16, 17), wherein the first chamber (15) and the second chamber (16) each have a circular ring segment-shaped cross-section and the third chamber (17) has a circular cross-section, wherein the first and the second chamber (15, 16) are arranged in a central double-walled tubular section concentrically around the third chamber (17), wherein the circular ring segments ment-shaped cross sections of the first and the second chamber (15, 16) have an equal arc measure < π and are arranged in their longitudinal extension between a first and a second longitudinal axial partition wall (18), and wherein the first partition wall (18) and the second partition wall (18) are arranged radially opposite one another in a section between an inner tube (21) and an outer tube (22) and are non-detachably connected to the inner tube (21) and the outer tube (22), wherein the partition walls (18) each have a shorter length than the first and the second chamber (15, 16) and thus, in the extension of the partition walls (18), a first and a second passage opening (19) are formed adjacent to the front-side outlet opening (14), and that the inner tube (21) has in its tube wall (26), adjacent to the front-side inlet opening (12), a passage opening (19) from the second chamber (16) in the third chamber (17) and wherein the filter element in the form of a partially double-walled tubular body (2) having a plurality of connected chambers (15, 16, 17) is produced entirely by 3D printing, characterized in that in the first and/or the second chamber (15, 16) at least in a central section - flow barriers (25), preferably in the form of truncated cones between the inner tube (21) and the outer tube (22), are arranged offset. Filter element (1) according to Claim 1 , characterized in that at least the surfaces in the interior of the ceramic tube body (2) have pores, wherein at least 50% of the pores have maximum dimensions between 10 µm and 100 µm. Filter element (1) according to Claim 1 or 2 , characterized in that the cross-sectional areas of the first and second chambers (15, 16) with circular ring-segment-shaped cross-sections in total in at least one section of the flue gas duct (20) have substantially the same surface area as the cross-sectional area of the third chamber (17). Filter element (1) according to one of the preceding claims, characterized in that the front-side inlet opening (12) comprises a grid (23) which has at least two intersecting webs (24) and/or is funnel-shaped. Filter element (1) according to Claim 1 , characterized in that the flue gas duct (20) has at least five interconnected chambers, wherein the first, second, fourth and fifth chambers each have a circular ring-segment-shaped cross-section with an radian measure < π, preferably < π/2 and are arranged concentrically around the third chamber, which has a circular cross-section. Filter element (1) according to one of the Claims 1 until 5 , characterized in that the diameter of the first end face (11) is equal to the diameter of the second end face (13), whereby the filter element (1) has a cylindrical shape. Filter element (1) according to one of the Claims 1 until 5 , characterized in that the diameter of the first end face (11) is different from the diameter of the second end face (13), whereby the outer contour of the filter element (1) is conical in the longitudinal direction and the filter element (1) has a truncated cone shape, wherein the cone angle α relative to the longitudinal axis of the filter element (1) is in the range between 0.3° and 6°, preferably between 0.5° and 3°, particularly preferably between 0.8° and 1.5°. Filter element (1) according to one of the preceding claims, characterized in that a trademark and/or a manufacturer's identification and/or an article number is or are incorporated into the outside of the tube wall (27) of the outer tube (22) of the filter element (1) by 3D printing and/or a laser beam. Filter element (1) according to one of the preceding claims, characterized in that the front outlet opening (14) of the flue gas duct (20) is arranged and designed to receive a filter plug made of synthetic or natural fibers. Method for producing a filter element or filter (1) in the form of a tubular body (2) according to the Claims 1 until 8th , characterized in that the method is a 3D printing method by means of a 3D printing device which comprises at least one storage for substrate particles, the substrate particles being selected from the group of ceramic substrate particles, and a control unit and a nozzle unit with at least one application nozzle and/or a laser unit and/or a movable workpiece holder and a drive system for moving the at least one application nozzle and/or the laser unit and/or the movable workpiece holder, with the steps: a) loading a basic configuration of the tubular body (2) in the form of a 3D layer model into the control unit, b) entering or loading the length and/or the diameter of the first end face (11) and the diameter of the second end face (13) of the tubular body (2) into the control unit, c) Calculating and creating a 3D layer model of the final configuration of the tubular body (2) and providing determined data by the control unit for the drive system and the nozzle unit, d) Transferring the determined data to the drive system and the nozzle unit, e) Setting a base plane for 3D printing using the 3D printing device, f) Printing the first end face (11) in the form of a first circular layer according to a predetermined layer-specific cross section of the tubular body (2) to be formed, g) Printing a second circular layer according to a predetermined layer-specific cross section of the tubular body (2) to be formed, h) Printing a further circular layer according to a predetermined layer-specific cross section of the tubular body (2) to be formed, i) Repeating step h) up to the level of the second end face (13) of the tubular body (2) to be formed, j) Printing the second end face (13) in the form of an annular layer of the tubular body to be formed (2). k) Providing the pipe body (2) for a subsequent, in particular thermal, treatment or coating.

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