DE102022104802A1 - METHOD OF MAKING A NOZZLE BODY AND NOZZLE BODY MADE WITH THE METHOD - Google Patents

Abstract

A suspension of quartz glass particles in a mixture of polymerizable binder and a solvent and a radical initiator is exposed to UV light and the binder is thereby polymerized. A primary structure that roughly corresponds to the outer dimensions of the desired nozzle body is injection molded from the resulting thermoplastic material with embedded glass particles using a mold. By heating for several hours, first residues of the non-curable component and finally the polymer binder are removed (debinding). The resulting porous secondary structure is filled with a filler and thermally sintered. The result is a raw body (1) comprising quartz glass, from which a nozzle body (14) is produced by means of a laser, in which at least one nozzle is formed.

Description

The present invention relates to a method for producing a nozzle body in which at least one nozzle is formed, and a nozzle body produced using the method.

Nozzle bodies are often used in technology when fluids such as liquids and aerosols are atomized from a supply line or a storage container, i.e. converted into an aerosol (possibly finer if an aerosol is used as the starting material), and metered, i.e. within a specified range Throughput to be discharged. Dosing systems that convert substances that are supplied as liquids at high pressure into gases by expanding when they flow out are also equipped with suitable nozzle bodies.

The fluid or fluid mixture supplied in each case is fed to the nozzle body through one or more inlet openings from the corresponding supply line or template and leaves it through one or more outlet paths. The outlet paths can then be designed differently depending on the intended application of the nozzle body.

A variety of applications are known to those skilled in the art from spray systems such as inhalers or simple spray cans, injection systems, etc.

Sufficiently small droplets, as may be necessary in particular to achieve pulmonary mobility in the medical field, can only be produced if the structures in the spray head are also sufficiently small. Reducing the fluid throughput at a given pressure drop also requires correspondingly small structures in the spray head.

In addition to the achievable droplet size and the resulting throughput, the droplet size distribution, the speed of exiting droplets and the spread or fanning out of an exiting spray jet are parameters that are significantly influenced by the geometric design of the spray head.

The design of the spray head geometry is always subject to limits for manufacturing reasons, so that not every geometry that is theoretically suitable for setting the above parameters can be produced as precisely as desired, even under economic conditions. For example, with conventional spray heads, the surface quality inside the outlet channels forming the nozzles can be insufficient, so that the pressure loss in the outlet channels is too high and the desired atomization performance is not achieved.

WO 94/07607 A1 describes for the production of a spray head intended for a high-pressure inhalation device, processing individual layers with a laser and then laminating them together. This procedure is extremely complex. Out of EP 1493492 A1 and EP 1386670 A2 spray heads are known in which fine channels are etched out of a silicon nozzle body by means of lithographic processes. Corresponding nozzle bodies are also very expensive to manufacture. In WO 2009/090084 A1 discloses the production of a spray head intended for a high-pressure inhalation apparatus by deep-drawing a metal sheet into which openings have previously been made by means of laser drilling. It is difficult to achieve sufficient manufacturing precision with this manufacturing method.

WO 2016/075433 A1 discloses the cost-effective production of a spray head as an injection-molded part made of plastic, with fine nozzle channels running in a straight line being introduced into thin-walled areas of the injection-molded part by means of laser drilling. Fine wall sections with a wall thickness of less than 200 µm are supported by thicker wall sections. Due to the fact that the laser-drilled channels are always straight during production, the nozzle head geometries that can be produced are limited to a certain extent. Various procedures are described for the formation of fine channel structures in injection molding, such as the use of contoured mold pins and the sealing of openly cast fine channel structures by means of a cover structure. The selection of possible plastics that have suitable casting properties and at the same time sufficient laser absorption capacity is limited. WO 2016/075433 A1 suggests the use of PMMA, PA, ABS or PET. The methods disclosed in the publication are described there for the production of nozzle heads in which two directed exiting spray jets collide in order to achieve fine aerosol particles.

Also for the production of nozzle heads with outlet channels, which are arranged in such a way that spray jets emerging from outlet openings in each case at least two of the outlet channels meet centrally at a respective impact point spaced apart from the outlet openings EP 3315207 A1 proposed to form the outlet channels entirely in quartz glass. In this case, the exit channels are produced by local laser action on the quartz glass and subsequent etching away from the quartz glass exposed to the laser action. For combining coarser with finer structures this publication proposes using small quartz glass spray heads in a spray head link made of a plastic, for example polyethylene, in order to keep production costs low. However, the combined use of glass components in plastic can again lead to manufacturing inaccuracies in the end product.

In view of the limitations to which the production and use of conventional nozzle bodies, in particular for spray cans, inhalers and atomizer pumps, are subject, the present invention is based on the object of at least reducing the disadvantages of the nozzle bodies known from the prior art and/or their manufacture. In particular, the invention is also based on the object of expanding the selection of available geometries for nozzle bodies that can be produced with justifiable economic effort, particularly in the ultra-fine range.

According to one aspect of the invention, this object is achieved with a method according to claim 1. In another aspect, the invention provides a nozzle body according to claim 13. Advantageous embodiments can be implemented in particular according to one of the dependent claims.

1. (i) Bereitstellen einer Primärstruktur, die in einem gehärteten organischen Binder dispergierte Glaspartikeln aufweist,
2. (ii) Entbindern der Primärstruktur durch thermische Behandlung, wodurch eine poröse Sekundärstruktur erhalten wird, und
3. (iii) Sintern der Sekundärstruktur zur Ausbildung des Rohkörpers.

The invention thus provides in particular a method in which glass material is removed from a raw body having the glass material by means of laser action in order to produce a nozzle body in which at least one nozzle is formed. The raw body is created by performing at least the following steps:

1. (i) providing a primary structure comprising glass particles dispersed in a cured organic binder,
2. (ii) debinding of the primary structure by thermal treatment, whereby a porous secondary structure is obtained, and
3. (iii) sintering the secondary structure to form the green body.

The production of the shaped body representing the raw body can advantageously be carried out essentially as in WO 2018/065093 A1 described, in which case the compositions containing quartz particles described there can also be used as starting material. In contrast to a possible treatment of the primary structure using laser light described there, however, according to the invention, as stated above, glass material is removed from the sintered raw body by means of laser action. Correspondingly, according to a preferred embodiment of the invention, a laser treatment of the secondary structure prior to sintering is omitted.

By ablating glass material by means of a laser after the production of the raw body, particularly fine structures can be produced with a special manufacturing quality, especially in the area of the nozzle, whereas the formation of coarser structures and the production of the basic shape of the nozzle body with a high surface quality is economical with the production of the raw body he follows.

Preferably, providing the primary structure includes curing the organic binder in a suspension containing the glass particles and the organic binder in a curable state, for example a WO 2018/065093 A1 disclosed suitable composition, and the casting, in particular injection molding of the binder composition containing the glass particles.

According to a particularly preferred embodiment, the at least one nozzle itself is at least partially formed by ablation with the aid of the laser, i.e. the laser is used to produce at least one continuous fluid path in the nozzle body, which has a nozzle inlet opening and a nozzle outlet opening.

Furthermore, the ablation with the help of the laser action can advantageously include a local wall thickness reduction. The local wall thickness reduction preferably reduces the thickness of a wall that laterally surrounds the at least one nozzle in the nozzle passage direction.

According to an advantageous development, the ablation by means of the laser action includes the local exposure of the glass material to the laser action and subsequent etching away from the glass material exposed to the laser action. The quartz glass exposed to the laser action can be etched away, for example, using hydrofluoric acid (HF) or preferably caustic potash (KOH). Such a manufacturing process is known per se, among other things, under the name SLE (Selective, Laser-Induced Etching, selective laser-induced etching) and Hermans, M. et al.: Selective, Laser-Induced Etching of Fused Silica at High Scan Speeds Using KOH, JIMN-Journal of Laser Micro/Nanoengineering Vol. 9, No. 2, 2014 published. Manufacturing machines that can be used to manufacture using the SLE process are commercially available under the name LightFab Microscanner.

Alternatively or additionally, other laser-ablating methods, in particular Laser drilling, in particular by means of femtosecond lasers, is used, but ablation by means of local laser action on the glass material and subsequent etching away of the glass material exposed to the laser action generally allows higher production quality.

The at least one nozzle can advantageously be designed with a smallest nozzle diameter of 300 μm or less, in particular 200 μm or less, and even 100 μm or less. The smallest diameter is taken to be the diameter of the largest circle inscribed in the locally smallest cross-sectional area of the nozzle channel through which flow can take place. In the case of a nozzle channel with a circular cross-section, this is the diameter at the narrowest point of the nozzle channel.

The method can advantageously include forming a nozzle of one of the following nozzle types: a Rayleigh nozzle, i.e. in particular one or more cylindrical nozzle holes, a double-jet nozzle, in particular a double-jet nozzle, which has outlet channels which are arranged in such a way that at least two of the outlet channels emerge from outlet openings Spray jets can meet centrally at a respective point of impact at a distance from the outlet openings, a multi-jet nozzle, a hollow cone nozzle, in particular with a tangential inlet, an annular gap nozzle, a fan jet nozzle, a full cone nozzle, a flat jet nozzle, a tongue nozzle, a spiral nozzle, a Borda nozzle, elbow nozzle and a turbulence nozzle and a mixing nozzle for mixing two or more different substances.

The present invention offers the advantage that, in the case of complex nozzle geometries, coarser structures of the nozzle body can be produced by the production of the raw body, in particular also by means of injection molding, and finer structures, in particular wall structures and nozzle channels or sections of nozzle channels that are thinned in the direction of nozzle flow, can be produced with the aid of laser action be formed.

The invention is explained in more detail below by way of example with reference to the attached schematic drawings. The drawings are not to scale; in particular, for reasons of clarity, the ratios of the individual dimensions to one another sometimes do not correspond to the dimensional ratios in actual technical implementations. Preferred exemplary embodiments are described, to which, however, the invention is not restricted. In principle, each variant of the invention described or indicated within the scope of the present application can be particularly advantageous, depending on the economic, technical and possibly medical conditions in the individual case. Unless stated otherwise, or insofar as it is fundamentally technically feasible, individual features of the described embodiments can be exchanged or combined with one another and with features known per se from the prior art.

• 1 ein Verfahrensfließbild einer Ausführungsform des erfindungsgemäßen Verfahrens,
• 2a die Querschnittsdarstellung eines erfindungsgemäßen bzw. erfindungsgemäß hergestellten Düsenkörpers mit darin ausgebildeter Zweistrahldüse,
• 2b eine Teilansicht des Düsenkörpers aus 2a in der Draufsicht von unten, wobei die Schnittebene der 2a als durchbrochene Linie B-B' angedeutet ist,
• 2c den Düsenkörper aus 2a und 2b zur Anwendung eingesetzt in den Sprühkopf einer Spraydose,
• 3a die Querschnittsdarstellung eines Rohkörpers, der mittels Lasereinwirkung zum Düsenkörper in 2a weiterverarbeitet wird,
• 3b den Rohkörper aus 3a in der Draufsicht von unten, wobei die Schnittebene der 3a wiederum als durchbrochene Linie B-B' angedeutet ist,
• 4a die Querschnittsdarstellung eines Rohkörpers für die Fertigung des Düsenkörpers in 5a und 5b,
• 4b den Rohkörper aus 4a in der Draufsicht von unten, wobei die Schnittebene der 4a als durchbrochene Linie A-A' angedeutet ist
• 5a die Querschnittsdarstellung eines erfindungsgemäßen bzw. erfindungsgemäß mittels Lasereinwirkung aus dem Rohkörper der 4a, 4b hergestellten Düsenkörpers mit 12 Rayleigh-Düsenlöchern,
• 5b eine Teilansicht des Düsenkörpers aus 5a in der Draufsicht von unten, wobei die Schnittebene der 5a als durchbrochene Linie A-A' angedeutet ist,
• 6 die Querschnittsdarstellung eines Rohkörpers für die Fertigung des Düsenkörpers in 7a und 7b,
• 7a die Querschnittsdarstellung eines erfindungsgemäßen bzw. erfindungsgemäß mittels Lasereinwirkung aus dem Rohkörper der 6 hergestellten Düsenkörpers mit Hohlkegeldüse mit radialem Einlauf, und
• 7b eine Teilansicht einer weiteren Querschnittsdarstellung des Düsenkörpers aus 7a mit orthogonal hierzu stehender Betrachtungseben von unten, wobei die Schnittebene der 7a in 7b als durchbrochene Linie B-B' angedeutet ist, und die Schnittebene der 7b in 7a als durchbrochene Linie A-A'.

It shows

• 1 a process flow diagram of an embodiment of the process according to the invention,
• 2a the cross-sectional representation of a nozzle body according to the invention or produced according to the invention with a two-jet nozzle configured therein,
• 2 B A partial view of the nozzle body 2a in the plan view from below, the cutting plane of the 2a is indicated as a broken line BB',
• 2c the nozzle body 2a and 2 B for use in the spray head of a spray can,
• 3a the cross-sectional view of a raw body, which is laser-cut into the nozzle body in 2a is further processed,
• 3b the raw body 3a in the plan view from below, the cutting plane of the 3a is again indicated as a broken line BB',
• 4a the cross-sectional representation of a raw body for the production of the nozzle body in 5a and 5b ,
• 4b the raw body 4a in the plan view from below, the cutting plane of the 4a is indicated as a broken line AA'
• 5a the cross-sectional view of an inventive or according to the invention by means of laser action from the raw body 4a , 4b manufactured nozzle body with 12 Rayleigh nozzle holes,
• 5b A partial view of the nozzle body 5a in the plan view from below, the cutting plane of the 5a is indicated as a broken line AA',
• 6 the cross-sectional representation of a raw body for the production of the nozzle body in 7a and 7b ,
• 7a the cross-sectional view of an inventive or according to the invention by means of laser action from the raw body 6 manufactured nozzle body with hollow cone nozzle with radial inlet, and
• 7b Figure 12 shows a partial view of another cross-sectional view of the nozzle body 7a with orthogonal thereto standing viewing level from below, the cutting plane of the 7a in 7b is indicated as a broken line BB ', and the sectional plane of 7b in 7a as broken line A-A'.

Corresponding elements are denoted by the same reference symbols in the drawing figures.

1 shows the flow chart of an embodiment of the method according to the invention, to which the invention is not limited. In step S1, a suspension of spherical quartz glass particles in a viscous mixture at room temperature of polymerizable binder and a solvent (non-curable component), for example hydroxyethyl methacrylate with phenoxyethanol in a volume ratio of 3: 1, and a radical initiator such as 2,2-dimethoxy-2-phenylacetophenone in this example. The proportion of the quartz glass particles, which preferably have particle diameters in the range from 7 to 100 nanometers, is selected in the given example with a volume ratio of approximately 1:1 to the binder.

Other polymerizable binders with or without non-curable components can also be used. A selection of compositions that can be used advantageously is, as stated above, in WO 2018/065093 A1 described.

In step S2, the binder is polymerized by supplying UV light at a wavelength of 365 nm. From the resulting thermoplastic material with embedded glass particles, a primary structure approximately corresponding to the external dimensions of the desired nozzle body is injection molded at a temperature above 70° C. in step S3 using a mold. The person skilled in the art can fall back on known injection molding processes here.

By heating for several hours in step S4 to initially 150°C (for about four hours), then 280°C (for about four hours) and finally 550°C (for about two hours), residues of the non-curable component (at the initially lower temperature to prevent it from igniting) and finally removing the polymer binder (debinding).

In step S5, the resulting porous secondary structure can advantageously be filled with a filler, preferably selected from the group consisting of silicon-based precursors and titanium-based precursors, in order to minimize shrinkage during the subsequent sintering. In particular when using silicon-based precursors, cavities in the secondary structure can be densified with quartz glass. In principle, all processes known per se from the prior art which are able to introduce fillers into the porous secondary structure, such as gas phase deposition, liquid infiltration and sol-gel processes, are suitable for filling the pores.

The filled secondary structure is then thermally sintered in step S6, for example initially at a temperature in the range from 700 to 1000° C. for a period of 1 to 3 hours and then at a temperature in the range from 1000 to 1500° C. for a period of 1 up to 2 hours. This results in a raw body 1 having quartz glass.

From the raw body 1 obtained, as for the exemplary embodiments described below 3a /3b, 4a/4b and 6, a nozzle body 14, in which at least one nozzle is formed, is now produced by means of laser action.

For this purpose, in the exemplary embodiment described, the material regions to be removed are first selectively exposed to laser exposure (step S7), and the exposed regions are etched out in the subsequent step S8 (selective laser-induced etching). Other methods of laser processing quartz glass that are known from the literature and from expert practice can also be used according to the invention.

A nozzle body 14 according to the invention with two outlet channels 15a, 15b is 2a as a cross section and in 2 B (partial) in top view (from below in 2a) shown. The cutting plane of 2a is in 2 B indicated as broken line BB'. 3a and 3b show a raw body produced according to steps S1-S6, which is further processed in steps S7 and S8 to form the nozzle body 14. The shaped body is in turn in 3a as a cross section and in 3b in top view (from below in 3a) pictured

By means of selective laser exposure and subsequent etching of the exposed areas (selective laser-induced etching), two essentially cylindrical outlet channels 15a, 15b with outlet openings 16a, 16b are formed in the quartz glass nozzle body 14 with a cylindrical basic shape, as well as a screen body 17 with a large number of screen openings 18, the diameter of which in the example shown corresponds approximately to the diameter of the outlet channels 15a, 15b in order to keep the latter away from blockages.

In general, depending on the application, sieve openings 18 with diameters between 2 μm and 150 μm are usually particularly advantageous. Even if the screen openings 18 are essentially cylindrical in the example shown, differently shaped screen openings 18 can also be advantageously implemented. For example, sieve trays 17 can be designed in the form of a grid with rectangular, in particular square, sieve openings 18 or in the form of a honeycomb with hexagonal sieve openings 18 . The screen body 17 is supported by the web 19 in order to be able to withstand larger pressure differences.

The space 20 through which fluid can flow between the inlet opening 21 of the nozzle body 14 and the outlet channels 15a, 15b is divided by the strainer body 17 . The screen body 17 and the wall area of the flow-through space 20 containing the outlet channels 15a, 15b are formed together in one piece by means of the selective laser-induced etching described above without a joint connecting the screen body and this wall area.

Flow and pressure conditions in the space 20 through which fluid can flow can be influenced in a targeted manner by the number, aspect ratio and arrangement of the screen openings 18 . Manufacturing by means of a laser increases the manufacturing accuracy.

On the other hand, the larger part of the space 20 through which a flow can pass, which is in front of the screen body 17, is already created in the raw body 1, as is the notch 22 on the upper side.

The outlet openings 16a, 16b of the outlet channels 15a, 15b formed in steps S7 and S8, which are arranged on the flanks of the notch 22, face one another. The angle α between the central axes of the outlet channels 15a, 15b, which intersect at point S, is approximately 80° in the example shown. The aspect ratio between the length l of the outlet channels 15a, 15b (along the respective shortest surface line of the cylindrical surface of the outlet channels 15a, 15b) and their cylinder diameter is approximately 2:1. Exact compliance with such a geometry is also simplified by manufacturing using the action of a laser.

2c shows the installation position of the nozzle body 14 in the spray head 5 of a spray can 2, only partially shown.

The spray head 5 is placed on the head 4 of the outlet pipe 3 of the spray container 6 . The spray container 6.ist made of conventional container material such as aluminum or tinplate.

The valve of the spray can 2 is similar to the valves of conventional spray cans and has a valve housing 7 which is sealed via the sealing ring 8 made of an elastic material such as caoutchouc or silicon rubber. The spring 9 inserted in the valve housing presses the closure capsule 11 against the sealing ring 8. By pressing the spray head 5 and spray container 6 together relative to one another, the outlet tube 3, which is beveled at the bottom, pushes the closure capsule downwards so that the spray material from the spray container 6 flows through the valve housing 7 and the outlet tube 3 can enter the supply channel 10 of the spray head 5. The spray head connecting link 13 holding the nozzle body 14 consists of thermoplastic or duroplastic material, e.g. polyethylene, polypropylene or polycarbonate.

5a and 5b show a by means of laser action, in particular selective laser-induced etching, from the in 4a and 4b illustrated body 1 produced nozzle body 14, wherein 4b and 5b again the bottom view of the in 5a or. 5b show each body shown in cross section. The broken line AA' symbolizes the respective cutting plane.

While the flow-through space 20 upstream of the Rayleigh nozzles 15 is formed in the raw body 1 according to the above steps S1-S6, the twelve cylindrical Rayleigh nozzles 15 and the local wall thickness reduction of the wall 23, which laterally surrounds the Rayleigh nozzles 15, are formed by laser action generated according to steps S7 and S8. The webs 19 left open by the laser effect ensure sufficient stability of the wall 23, which is reduced in thickness (in the axial direction of the nozzles 15).

7a shows the cross-sectional view of a nozzle body 14 according to the invention, wherein the sectional plane of the 7b is indicated as a broken line AA'. The cutting plane of 7a is in 7b indicated as broken line BB'. The cutting planes of 7a and 7b are therefore perpendicular to each other. 6 shows in one 7a Corresponding cross-sectional view shows the raw body 1 with a basic cylindrical shape, in which a cylindrical-conical cavity 24 with a largely tangential fluid inlet 25 and axial fluid outlet 16 is formed by means of selective laser exposure and subsequent etching of the exposed areas (selective laser-induced etching) in order to produce the nozzle body 14.

The respective smallest diameter of the fluid inlet 25 and fluid outlet 16 d _a is less than 200 μm. With the mentioned manufacturing process of selective laser-induced etching can also reach diameters of just a few micrometers.

The axis of symmetry a of the conical section of the cavity 24 is also the axis of symmetry of the fluid outlet 16. In the example shown, the fluid outlet 16 ends with a conical enlargement and a sharp tear-off edge in order to promote fluid atomization.

Liquid to be atomized is supplied to the fluid inlet 25 via the inlet 21 and the annular antechamber 26, which is also produced by selective laser-induced etching. Between the inlet 21 and the antechamber 26, the liquid to be atomized flows through the screen body 17 (not mandatory). Its openings 18 each have a smallest diameter of one third of the smallest diameter of the fluid inlet 25. The screen body 17 preserves the fluid inlet 25 and the fluid outlet 16 from clogging. Several fluid inlets 25 can also be distributed over the circumference.

The through-flow space 20 upstream of the screen body 17 is already created in the raw body 1 produced by means of steps S1-S6.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was 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.

Patent Literature Cited

• WO 9407607 A1 [0008]
• EP 1493492 A1 [0008]
• EP 1386670 A2 [0008]
• WO 2009090084 A1 [0008]
• WO 2016075433 A1 [0009]
• EP 3315207 A1 [0010]
• WO 2018065093 A1 [0014, 0016, 0028]

Non-patent Literature Cited

• Hermans, M. et al.: Selective, Laser-Induced Etching of Fused Silica at High Scan Speeds Using KOH, JIMN-Journal of Laser Micro/Nanoengineering Vol. 9, No. 2, 2014 [0019]

Claims (13)

Method for producing a nozzle body in which at least one nozzle is formed, wherein a raw body comprising glass material is produced by carrying out at least the following steps, (i) providing a primary structure comprising glass particles dispersed in a cured organic binder, (ii) debinding of the primary structure by thermal treatment, whereby a porous secondary structure is obtained, and (iii) Sintering of the secondary structure to form the raw body, and glass material being removed from the raw body by means of the action of a laser. procedure according to claim 1 , wherein the at least one nozzle is formed at least partially by ablating with the aid of the action of a laser. Method according to one of the preceding claims, wherein the ablation with the aid of the laser action comprises in particular a local wall thickness reduction. procedure according to claim 3 , wherein the local reduction in wall thickness reduces the thickness of a wall which laterally surrounds the at least one nozzle in the nozzle passage direction. A method according to any one of the preceding claims, wherein the laser ablation comprises locally exposing the glass material to the laser action and then etching away the laser exposed glass material. Method according to one of the preceding claims, wherein the provision of the primary structure comprises the hardening of the organic binder and the casting, in particular injection molding, of a mass having the glass particles and the organic binder. Method according to one of the preceding claims, wherein a laser treatment of the secondary structure before sintering is omitted. Method according to one of the preceding claims, wherein the at least one nozzle is formed with a smallest nozzle diameter of 300 µm or less, in particular 200 µm or less. A method according to any one of the preceding claims, which includes forming a hollow cone nozzle or full cone nozzle in the nozzle body. A method according to any one of the preceding claims including forming at least one Rayleigh nozzle hole in the nozzle body. A method according to any one of the preceding claims, which comprises forming at least two nozzle channels forming a multi-jet nozzle in the nozzle body. A method according to any one of the preceding claims, which includes forming at least one flat jet nozzle or fan jet nozzle in the nozzle body. Nozzle body manufactured by a method according to any one of the preceding claims.

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