EP3702496A1 - Mould and method for manufacturing a mould for extruding cellulose moulded bodies - Google Patents

Abstract

The invention relates to a molding tool (1, 51) for extruding cellulosic molded bodies (4) from a spinning mass (2), with an entry side (6, 56) and an exit side (7, 57) for the spinning material (2), with at least one Nozzle body (8, 58a, 58b, 58c), having a flat carrier (9, 59a, 59b, 59c) with extrusion openings (10, 60) which move the carrier from the inlet side (6, 56) to the outlet side (7, 57) penetrate and on the exit side (7, 57) have an opening diameter (12, 62) and through which the spinning mass (2) is extruded to form the cellulosic molded bodies (4). In order to provide a molding tool of the type mentioned at the beginning, which can be produced more simply and cost-effectively and at the same time has excellent strength and pressure stability, it is proposed that the ratio of thickness (13, 63) of the carrier (9, 59a, 59b, 59c) to Mouth diameter (12, 62) of the extrusion openings (10, 60) on the outlet side (7, 57) is at least 6: 1, preferably at least 10: 1, and that the extrusion openings (10, 60) by applying laser energy to the carrier ( 9, 59a, 59b, 59c) were introduced.

Description

Technical area

The invention relates to a molding tool for the extrusion of cellulosic molded bodies from a spinning mass, with an entry side and an exit side for the spinning mass, with at least one nozzle body, having a flat support with extrusion openings which penetrate the support from the entry side to the exit side and an opening diameter at the exit side have and through which the spinning mass is extruded to form the cellulosic moldings.

The invention also relates to a method for producing the molding tool and a method for producing cellulosic molded bodies using the molding tool.

State of the art

Molds for the extrusion of cellulosic moldings of the type mentioned (also known as "spinnerets" or "spinnerettes") usually have to meet numerous high quality criteria in order to be suitable for spinning highly viscous cellulose solutions. For example, high requirements in terms of quality and dimensional accuracy (profile shape, mouth diameter and positioning) of the extrusion openings must be met in order to obtain a homogeneous bundle of shaped bodies and to avoid sticking of the individual shaped bodies in the shaped body bundle. In addition, the roughness of the inner walls of the extrusion openings and the sharp edges and absence of burrs in the extrusion openings play a decisive role in shaping the molded bodies (which are formed from the extruded spinning mass on the exit side of the extrusion opening) and in avoiding spinning defects (such as breakage or tearing off) or gluing of moldings), caused for example by irregularities or burrs of the extrusion openings on the exit side arise. There are also high demands on the strength of the molding tools, since they are exposed to very high pressures of up to 150 bar during the extrusion of the spinning mass.

From the EP 0 430 926 B1 and the WO 94/28211 A1 mold tools for extrusion of cellulosic moldings from a spinning mass are known which can be used in processes for producing cellulosic moldings - such as the viscose or lyocell process. The extrusion openings are usually made in a carrier by mechanical drilling or piercing. However, this places special demands on the material of the carrier, as it must have sufficient ductility on the one hand to be able to be machined with the drilling or piercing tool, and on the other hand withstand the very high pressures in the viscose or lyocell process of up to 150 bar got to. These requirements are for example in the EP 0 430 926 B1 by using a plate made of a softer, easily machinable material (such as gold, silver or tantalum), in which the extrusion openings are made, in a support made of stainless steel. Due to the special combination of materials, the extrusion openings can easily be made in the mold and a high level of strength is still achieved. However, such molding tools have the disadvantage that the materials used are very expensive, and the assembled molding tools are subject to a very complex manufacturing process, since the platelets have to be subsequently introduced into the carrier and connected to it. In addition, mechanical processing methods such as drilling or pricking create burrs on the extrusion openings, which have to be removed in additional, complex post-processing steps (e.g. by polishing). Likewise, only limited positioning accuracy and reproducibility can be achieved in such mechanical processing methods, which usually leads to high tolerances in the extrusion openings.

The WO 2005/005695 A1 shows a method for producing molds of the aforementioned type, the extrusion openings being introduced into a carrier of the mold by means of electron beams. Forming tools produced in this way overcome the problem of the choice of material, since the extrusion openings can be made directly in the carrier, which means that the extrusion openings can be made separately in a plate and there is no need to subsequently assemble the components. In addition, such extrusion openings introduced into the molding tools by means of electron beams have an advantageously reduced roughness and high sharpness with a small burr. However, the extrusion openings made in the carrier by electron beams are severely limited in their profile shape and have a high degree of scatter or tolerance in their mouth diameter, since the effect of the electron beams can only be controlled and reproduced to a limited extent. In addition, the extrusion openings must be introduced by electron beams in a high vacuum, which in turn requires a complex manufacturing process.

Disclosure of the invention

It is therefore an object of the invention to provide a molding tool of the type mentioned at the beginning, which can be produced more simply and cost-effectively and at the same time has excellent strength and pressure stability and the extrusion openings have lower tolerances in terms of mouth diameter, position and profile shape.

The invention achieves the stated problem in that the ratio between the thickness of the carrier and the mouth diameter of the extrusion openings on the exit side is at least 6: 1, and that the extrusion openings were introduced into the carrier by applying laser energy.

If the ratio of the thickness of the carrier to the mouth diameter of the extrusion openings on the outlet side is at least 6: 1, a particularly pressure-stable nozzle body with high strength can be created, which can ensure a long service life at high pressure. This pressure stability means that plastic deformations of the nozzle body can be avoided during its service life under normal operating conditions, while a small amount of load-dependent elastic deformations is unavoidable. This strength can be further improved if the above-mentioned ratio is at least 10: 1 or particularly preferably at least 12: 1 or at least 15: 1. If the extrusion openings are also made in the carrier by applying laser energy, the molding tool can be made very simple Mark manufacturability. The extrusion openings can be introduced into the carrier of the molding tool with a very high degree of dimensional accuracy, which means that a molding tool can be created that meets the high quality requirements and tight dimensional tolerances with regard to the mouth diameter and positioning. In particular, through the use of laser radiation, dimensional tolerances of the critical variables, such as the mouth diameter, hole geometry and cross-section of the extrusion openings, and the distance between the extrusion openings of less than 2% can be achieved. The laser radiation can also directly create smooth and burr-free extrusion openings, which means that further post-processing steps on the molding tool can be omitted. Such post-processing steps, such as grinding or polishing, require high mechanical loads and can produce adverse stress effects in the carrier. A particularly easy to manufacture and reliable molding tool with low dimensional tolerances can thus be created.

In the context of the invention, shaped bodies are in particular the filaments emerging from the extrusion openings, which can subsequently be used for the production of continuous or staple fibers. Such filaments or fibers preferably have titers of greater than or equal to 0.7 dtex in the context of the invention.

In general, it is stated that the invention relates to molds for the production of regenerated cellulosic moldings with an opening diameter of the extrusion opening on the exit side of greater than or equal to 40 μm, in particular greater than or equal to 45 μm, preferably greater than or equal to 50 μm, particularly preferably between 70 μm and 150 μm . If the mouth diameter is below 40 µm, the molding tools are particularly suitable for producing microfibers with a fiber titer of less than 0.7 dtex. However, the molding tools of the present invention are used in the production of cellulosic fibers with a titer of usually greater than or equal to 0.7 dtex, for which extrusion openings with an opening diameter greater than 40 μm are suitable.

If the thickness of the carrier is at least 600 μm, a molding tool with sufficient strength and durability of the nozzle body can be used be created, which can be made large enough at the same time to allow an advantageous production throughput. In particular, the preferred thickness of the carrier is at least 800 μm, or particularly preferably 1000 μm. If the carrier has a thickness in this range, it can be ensured that in regular operation, at operating pressures of up to 100 bar, such as in a process for the production of regenerated cellulosic molded bodies according to the Lyocell type (Lyocell process) are common, there is no plastic deformation of the carrier. A plastic deformation of the carrier can change the geometry of the extrusion openings disadvantageously as well as negatively affect the exit behavior of the moldings from the mold. In addition, it can be ensured that the carrier can be loaded with a pressure of up to 150 bar even in the event of overpressure events, without the carrier breaking or irreversible structural damage occurring. Forming tools having a carrier with a thickness of less than 600 μm are only suitable to a limited extent for use in such processes, since they do not have the necessary strength to permanently withstand the high pressures or only allow a very limited throughput.

If the extrusion openings are free of burrs on the exit side, a molding tool can be created in which a disadvantageous sticking of the molded bodies after exiting the extrusion openings can be avoided. Burrs on the extrusion openings can have the disadvantage that the extruded moldings do not just emerge from the extrusion openings, but are deflected by the burr and come into contact with an adjacent molding and stick together, causing spinning errors that result in an interruption and restart (re-spinning ) make the process necessary or lead to reject production.

Particularly flexible molds for different processes for the extrusion of cellulosic moldings can be created if the nozzle body is annular or rectangular. In addition, the molding tool can have several such nozzle bodies. For example, it is possible for the molding tool to have a plurality of rectangular nozzle bodies that adjoin one another. Such a molding tool can be manufactured particularly easily and can be more cost-effective.

If the molding tool has at least one first web, which is firmly connected to the nozzle body and protrudes from the nozzle body in the direction of the inlet side, then on the one hand the stability and strength of the support can be further improved, since the web is a pressure load on the nozzle body or in particular the support counteracts, and on the other hand, a guide surface for the spinning mass can be created by the web, since this can ensure an efficient transport of the spinning mass to the extrusion openings. In addition, the formation of dead spaces is avoided by the suitable design of the web and thus the quality of the molded bodies extracted thereby is improved.

The strength of the carrier can be further increased significantly if the molding tool has at least one second web, the nozzle body extending between the first web and the second web. The second web, like the first web, is cohesively connected to the nozzle body and protrudes from the nozzle body in the direction of the inlet side. In this way, the first and the second web can function in particular as an edge-side support of the nozzle body and thus reliably dissipate the pressure loads that act on the carrier during the extrusion. In addition, the first and second webs can jointly form a channel for guiding the spinning mass on the entry side. A particularly reliable and stable molding tool can thus be created.

The molding tool can be particularly advantageous if the web extends, at least in sections, essentially normal to the nozzle body. Through the section which extends essentially normal to the nozzle body, the spinning mass can be directed strongly in the direction of the extrusion orifices and thus a directional mass flow can be maintained.

If the distance normal to the longitudinal extension of the nozzle body between the first and second webs is at least less than 100 times the thickness of the carrier, the molding tool can prove itself with excellent stability and resistance to deformation due to the high pressure of the spinning mass.

Advantageously, the first web can completely encircle the second web and thus a particularly simple form tool can be created. This can be particularly useful for use in a molding tool an annular nozzle body, the annular nozzle body extending between the first and second webs.

If the molding tool also has a flange with at least one flange leg on the inlet side, the flange leg connecting to the web, an easily manageable and flexibly exchangeable molding tool can be created, which can be quickly and easily attached to a spinning machine via the flange. If the flange leg protrudes outwards from the molding tool, it can also be ensured that the spinning mass can flow freely onto the nozzle body from the inlet side without any obstacles and thus a uniform extrusion through the molding tool is made possible.

With regard to the method for producing the molding tool according to one of claims 1 to 11, the invention has the object of providing a simple and cost-effective method which nevertheless enables high precision.

The object with regard to the production method is achieved by the subject matter of claim 12.

If a molding tool is produced according to one of claims 1 to 11, in which the extrusion openings are introduced into the carrier from the entry side of the molding tool by applying laser energy to the carrier and burr-free extrusion openings are generated in the carrier on the exit side without further post-processing Particularly simple and reproducible manufacturing processes for molding tools are created. The use of laser radiation also makes complex post-treatment of the extrusion openings obsolete, since the extrusion openings introduced directly into the carrier can meet all of the quality criteria placed on the molding tools. This applies both to the roughness and absence of burrs in the extrusion openings, as well as to the positioning accuracy and the opening diameter. If the laser energy is applied to the carrier by pulsed laser radiation, particularly low manufacturing tolerances can be maintained for the extrusion openings. Laser radiation with a pulse duration between 100 fs and 100 ns and pulse energies between 1 μJ and 1000 μJ has proven to be particularly suitable. The pulsed laser radiation can are preferably applied to the carrier in a percussion drilling process or a helical drilling process and thus produce extrusion openings with high precision and low manufacturing tolerances.

If the extrusion openings are introduced into the carrier after the material connection of the carrier with a web, a particularly reliable and reproducible manufacturing method can be provided. The production of a material connection between the carrier and a web inevitably leads to mechanical loads on the carrier material and thus to an undesirable impairment or change in the extrusion openings. By subsequently introducing the extrusion openings into the fully assembled or fully formed molding tool, such mechanical loading of the extrusion openings can be avoided, in particular if the introduction of the extrusion openings takes place as the last, final process step.

The molding tool according to the invention according to one of claims 1 to 11 can be particularly distinguished when it is used in a process for the production of regenerated cellulosic molded bodies, in which a spinning mass containing cellulose is extruded through the molding tool and is precipitated in a spinning bath to close the molded body produce.

Such a process can particularly preferably be a Lyocell process in which the spinning mass contains a tertiary amine oxide in which the cellulose is dissolved and the spinning bath has a mixture of water and tertiary amine oxide.

Brief description of the drawings

Fig. 1

eine Schnittansicht entlang I-I gemäß Fig. 2 auf ein Formwerkzeug entsprechend einer ersten Ausführungsform,

Fig. 2

eine Draufsicht auf das Formwerkzeug gemäß Fig. 1,

Fig. 3

eine abgerissene Schnittansicht entlang II-II gemäß Fig. 4 auf ein Formwerkzeug gemäß einer zweiten Ausführungsform,

Fig. 4

eine Draufsicht auf das Formwerkzeug gemäß Fig. 3, und

Fig. 5

eine teilweise abgerissene Schnittansicht auf eine Spinnmaschine mit einem erfindungsgemäßen Formwerkzeug gemäß Fig. 1.

The embodiments of the invention are described below with reference to the drawings. Show it:

Fig. 1

a sectional view along II according to Fig. 2 on a molding tool according to a first embodiment,

Fig. 2

a plan view of the mold according to Fig. 1 ,

Fig. 3

a broken sectional view along II-II according to Fig. 4 on a molding tool according to a second embodiment,

Fig. 4

a plan view of the mold according to Fig. 3 , and

Fig. 5

a partially broken sectional view of a spinning machine with a molding tool according to the invention according to Fig. 1 .

Ways of Carrying Out the Invention

In Fig. 1 an annular mold 1 according to a first embodiment of the invention is shown, which is in a spinning device 100 according to Fig. 5 and is used in a process for the extrusion of cellulosic molded bodies 4. The molding tool 1 has an entry side 6 for the spinning mass 2 and an exit side 7 for the extruded spinning mass 3 (cf. Fig. 5 ). In addition, a nozzle body 8 with a flat carrier 9 is provided in the mold 1. The nozzle body 8 can be formed in one piece with the rest of the molding tool 1 (for example by deep drawing, milling, etc.), or connected to it in some other way (for example by welding, etc.).

The carrier 9 has extrusion openings 10 which penetrate it from the inlet side 6 to the outlet side 7. On the outlet side 7, the extrusion openings 10 form an opening 11 with an opening diameter 12. The size of the mouth diameter 12 significantly influences the titer (or diameter) of the extruded cellulosic molded body 4. In addition, the cross-sectional shape of the extrusion opening 10 can control the extrusion behavior and the geometry of the molded body 4. For example, the exit behavior of the spinning mass 2 from the extrusion openings 10 can be changed in order to prevent the extruded spinning mass 3 from sticking before it precipitates in the spinning bath 5. Preferred cross-sectional shapes of the extrusion openings 10 can have a course that tapers towards the exit side 7, as shown in FIG Fig. 1 is shown. The cross-sectional shape can, however, be varied as desired by the laser radiation, with which, for example, hourglass-shaped courses widening towards the exit side 7 are possible.

The extrusion openings 10 have an opening diameter 12 of between 70 and 150 μm. With such mouth diameters 12 it can be ensured that fibers or filaments with a titer of greater than 0.7 dtex are produced as extruded cellulosic molded bodies 4. In another In a preferred embodiment of the invention, regenerated cellulosic fibers with a titer between 1.0 and 2.5 dtex are produced.

The ratio between the thickness 13 of the carrier 9 and the mouth diameter 12 of the extrusion opening 10 is at least 6: 1, which ensures that the carrier 9 is sufficiently stable against the high pressures caused by the spinning mass 2. In further preferred embodiments of the invention, a ratio of at least 10: 1, of at least 12: 1, or of at least 15: 1 is selected.

The thickness 13 of the carrier 9 is at least 600 μm. The carrier 9 can thus permanently withstand a pressure load of up to 150 bar from the inlet side 6. In a further embodiment, the preferred thickness 13 of the carrier 9 is at least 800 μm, or preferably 1000 μm, in order to guarantee a particularly high stability of the carrier 9.

The extrusion openings 10 were made in the carrier 9 by the application and action of laser energy therein. As a result, the molding tool 1 can be manufactured very easily in terms of process technology. In addition, the laser radiation acting in the material of the carrier 9 achieves particularly high dimensional accuracies in the positioning, dimensions and geometry of the extrusion openings 10. In particular, the extrusion openings 10 have a constant mean distance 14 from one another, which is between 50 and 1000 μm, the standard deviation of the distance 14 being a maximum of 1%. In order to avoid the fibers sticking together when they exit the extrusion openings 10, larger spacings 14 of 250 to 800 μm are usually used. The extrusion openings 10 can be arranged in any regular pattern (for example radial, grid-shaped, etc.) or irregularly distributed over the carrier 9. A standard deviation of the mouth diameter 12 of less than 2% is also achieved by the laser radiation. In addition, the extrusion openings 10 introduced into the carrier 9 by the laser radiation do not have any burrs on the exit side 7 after they have been introduced and therefore do not have to be subjected to further post-processing steps such as grinding or polishing, which can adversely affect the geometry of the extrusion openings 10. In particular, the burr-free and smooth extrusion openings 10 further ensure that the Do not stick individual strands of the extruded spinning mass 3 to one another before they precipitate to form the shaped bodies 4 in the spinning bath 5.

That in the Figs. 1 and 2 The molding tool 1 shown with an annular nozzle body 8 has a first web 15 and a second web 16, which are both materially connected to the annular nozzle body 8. The webs 15, 16 can be formed approximately in one piece with the carrier 9 of the nozzle body 8, for example by deep-drawing or milling the molding tool 1 as a whole, or, for example, by being welded to it in a materially bonded manner. The annular nozzle body 8 extends between the first and second webs 15, 16. The webs 15 and 16 protrude from the nozzle body 8 in the direction of the inlet side 6. As a result of the material connection with the nozzle body 8, the webs 15, 16 act as edge-side supports for the carrier 9, which means that the carrier 9 can withstand a higher pressure load from the spinning mass 2. Due to the ring-shaped configuration of the nozzle body 8, the first web 15 completely surrounds the second web 16 and the nozzle body 8. The two webs 15 and 16 thus always run parallel to one another and maintain a constant normal spacing 17 transversely to the longitudinal extension 18 of the nozzle body 8, along the carrier 9, to one another. The normal distance 17 is at most 100 times the thickness 13 of the carrier 9 in order to ensure the maximum stability of the nozzle body 8.

In the interior of the molding tool 1, the webs 15 and 16 act as guide surfaces 19 for the spinning mass 2, which advantageously support the flow behavior of the highly viscous spinning mass 2 and prevent the formation of dead spaces within the molding tool 1. The webs 15, 16 thus form a guide channel 20 for the spinning mass 2 from the entry side 6. The webs 15 and 16 extend, as in FIG Fig. 1 shown, preferably normal to the nozzle body 8 and thus normal to the carrier 9.

The molding tool 1 also has a flange 23, via which the molding tool 1 is connected to a spinning device 100 - as in FIG Fig. 5 shown - can be connected. The flange 23 has two flange legs 21, 22 which each adjoin the webs 15 and 16 on the inlet side 6 and which protrude outwardly from the webs 15 and 16 and thus the molding tool 1. The flange legs 21, 22 do not hinder the guide channel 20 for the Spinning mass 2 and thus reliably avoid a negative influence on the flow conditions in the guide channel 20.

In the Figures 3 and 4 a molding tool 51 according to a second embodiment is shown, which has a plurality of rectangular nozzle bodies 58a, 58b, 58c. The molding tool 51, like the molding tool 1, can be used in a spinning device 100 according to FIG Fig. 5 and used in a method for extrusion of cellulosic molded bodies 3. In an equivalent manner to that described for the first embodiment, the molding tool 51 has an entry side 56 for the spinning mass 2 and an exit side 57 for the extruded spinning mass 3 (cf. Fig. 5 ).

The molding tool 51 has three nozzle bodies 58a, 58b and 58c, each of which comprises a flat carrier 59a, 59b, 59c. In general, it should be mentioned that a molding tool 51 as shown in FIGS Figures 3 and 4 shown need not be limited to three nozzle bodies. Any other number and arrangement of nozzle bodies in the molding tool is also possible.

The nozzle bodies 58a, 58b, 58c are connected to the rest of the molding tool 51 with a material fit, preferably by weld seams 73. The carriers 59a, 59b, 59c each have extrusion openings 60 which penetrate them from the entry side 56 to the exit side 57 and were introduced into them by the action of laser radiation. The extrusion openings 60 each form an opening 61 with an opening diameter 62 on the outlet side 57. As described for the first embodiment, the mouth diameter 62 can be varied in order to change the titer of the extruded cellulosic molded bodies 4. The preferred opening diameter 62 of the extrusion openings 60 is between 70 and 150 μm in order to produce cellulosic molded bodies 4, in particular fibers, with a titer of greater than 0.7 dtex. By introducing the extrusion openings 60 by means of laser radiation, a standard deviation of the mouth diameter 62 of less than 1% is also achieved. Regenerated cellulosic fibers with a titer between 1.0 and 2.5 dtex are particularly preferably produced. The cross-sectional shapes of the extrusion openings 60 can also be changed as described for the first embodiment in order to control the exit behavior of the extruded spinning mass 3.

The carriers 59a, 59b, 59c of the nozzle bodies 58a, 58b, 58c have a preferred thickness 63 of at least 600 μm. In further advantageous refinements of this embodiment, the thickness 63 is at least 800 μm, or at least 1000 μm, in order to obtain a particularly permanently stable molding tool 51 which withstands the high pressures of up to 150 bar acting from the inlet side 56. The ratio between the thickness 63 of the supports 59a, 59b, 59c and the opening diameter 62 of the extrusion openings 60 is at least 6: 1 in order to achieve the necessary stability. In preferred embodiments of the invention, the ratio is at least 10: 1, at least 12: 1, or at least 15: 1.

Since the extrusion openings 60 are introduced into the supports 59a, 59b, 59c by applying laser energy to them, a very high degree of dimensional accuracy in the positioning and dimensions of the extrusion openings 60 is achieved. As in Fig. 4 As shown, the extrusion openings 60 are arranged at a constant distance 64 of 50 to 1000 μm from one another, the standard deviation being a maximum of 2% of the distance 64. In addition, the extrusion openings 60 can be made essentially burr-free by laser radiation, which makes further grinding or polishing steps superfluous and thus avoids the formation of stress effects in the carriers 59a, 59b, 59c.

The molding tool 51 has first webs 65a, 65b, 65c, 65d, which are provided on the outside of the molding tool 51. In the interior of the molding tool 51, second webs 66a, 66b are provided, which extend in the form of ribs between the first webs 65c and 65d and are materially connected to them. The nozzle bodies 58a and 58c extend transversely to their longitudinal extension 68 between a first web 65a, 65b and a second web 66a, 66b. The nozzle body 58b extends between the second webs 66a, 66b. Web 65a, 65b, 65c, 65d, 66a, 66b and supports 59a, 59b, 59c of the nozzle bodies 58a, 58b, 58c are materially connected to one another via weld seams 73. The webs 65a, 65b, 65c, 65d, 66a, 66b are preferably designed together in one piece (e.g. as a milled, deep-drawn, rolled, etc. part) and protrude from the nozzle bodies 58a, 58b, 58c in the direction of the inlet side 56.

The webs 65a, 65b, 66a, 66b run parallel to one another and maintain a constant normal distance 67 (normal to the longitudinal extension 68) along the Carriers 59a, 59b, 59c to one another. The normal distance 67 is at most 100 times the thickness 63 of the supports 59a, 59b, 59c, so that the greatest possible stability of the nozzle bodies 58a, 58b, 58c is achieved.

In the interior of the mold 51, the webs 65a, 65b, 65c, 65d, 66a, 66b act as guide surfaces 69 for the spinning mass 2. Thus, a guide channel 70 is created by the webs 65a, 65b, 65c, 65d, 66a, 66b from the inlet side 56 , through which the spinning mass 2 is guided to the extrusion openings 60.

In addition, the molding tool 51 has a flange 73 via which the molding tool 51 can be connected to a spinning device 100 in a non-positive manner. Four flange legs 71a, 71b, 71c and 71d, which each adjoin a first web 65a, 65b, 65c, 65d, form the flange 73, which protrudes outward from the molding tool 51 on the entry side 56 and surrounds the molding tool 51.

Fig. 5 shows a spinning device 100 in which, according to a method for producing regenerated cellulosic molded bodies 4, a spinning mass 2 is extruded through a molding tool 1, according to the first embodiment of the invention, to form the cellulosic molded bodies 4. In order to obtain the molded bodies 4, in such a method for producing regenerated cellulosic molded bodies 4, the extruded spinning mass 3 is passed after extrusion through an air gap 8 into a spinning bath 5, where the cellulose precipitates from the extruded spinning mass 3. According to a further preferred embodiment of the invention, the method for producing the regenerated molded bodies 4 is a Lyocell method, in which the spinning mass 2 contains a solution of cellulose in a tertiary amine oxide. The spinning bath 5 for precipitating the extruded spinning mass 3 contains a mixture of water and a tertiary amine oxide (for example NMMO - N-methylmorpholine-N-oxide).

Claims (15)

Molding tool for the extrusion of cellulosic molded bodies (4) from a spinning mass (2), with an entry side (6, 56) and an exit side (7, 57) for the spinning mass (2), with at least one nozzle body (8, 58a, 58b, 58c ), having a flat carrier (9, 59a, 59b, 59c) with extrusion openings (10, 60) which penetrate the carrier from the inlet side (6, 56) to the outlet side (7, 57) and on the outlet side (7, 57 ) have a mouth diameter (12, 62) and through which the spinning mass (2) is extruded to form the cellulosic molded bodies (4), characterized in that the ratio of thickness (13, 63) of the carrier (9, 59a, 59b, 59c ) to the mouth diameter (12, 62) of the extrusion openings (10, 60) on the exit side (7, 57) is at least 6: 1, preferably at least 10: 1, and that the extrusion openings (10, 60) by applying laser energy in the Carriers (9, 59a, 59b, 59c) were introduced. Mold according to Claim 1, characterized in that the thickness (13, 63) of the carrier (9, 59a, 59b, 59c) is at least 600 µm, preferably at least 800 µm. Mold according to claim 1 or 2, characterized in that the extrusion openings (10, 60) on the exit side (7, 57) are free of burrs. Molding tool according to one of Claims 1 to 3, characterized in that the nozzle body (8, 58a, 58b, 58c) is annular or rectangular. Mold according to one of Claims 1 to 4, characterized in that the mold (51) has a plurality of nozzle bodies (58a, 58b, 58c). Molding tool according to one of claims 1 to 5, characterized in that the molding tool (1, 51) has at least one first web (15, 65a, 65b, 65c, 65d) which is firmly bonded with the nozzle body (8, 58a, 58b, 58c ) and protrudes from the nozzle body (8, 58a, 58b, 58c) in the direction of the inlet side (6, 56). Molding tool according to Claim 6, characterized in that the molding tool (1, 51) has at least one second web (16, 66a, 66b), the nozzle body (8, 58a, 58c) being located between the first web (15, 65a, 65b) ) and the second web (16, 66a, 66b). Mold according to claim 6 or 7, characterized in that the web (15, 16, 65a, 65b, 65c, 65d, 66a, 66b) extends at least in sections essentially normal to the nozzle body (8, 58a, 58b, 58c). Mold according to claim 7 or 8, characterized in that the distance (17, 67) normal to the longitudinal extent (18, 68) of the nozzle body (8, 58a, 58b, 58c) between the first web (15, 65a, 65b) and the second web (16, 66a, 66b) is at least less than 100 times the thickness of the carrier (9, 59a, 59b, 59c). Mold according to one of Claims 7 to 9, characterized in that the first web (15, 65a, 65b, 65c, 65d) completely surrounds the second web (16, 66a, 66b). Molding tool according to one of Claims 6 to 10, characterized in that the molding tool (1, 51) has a flange (23, 73) with at least one flange leg (21, 22, 71a, 71b, 71c, 71d), the flange leg (21, 22, 71a, 71b, 71c, 71d) adjoining the web (15, 16, 65a, 65b, 65c, 65d) and the molding tool (1, 51) protruding outward. Method for producing a molding tool (1, 51) according to one of Claims 1 to 11, in which the extrusion openings (10, 60) are created by applying laser energy to the carrier (9, 59a, 59b, 59c) from the entry side (6, 56 ) of the molding tool (1, 51) are introduced into this and without further post-treatment on the outlet side (7, 57) burr-free extrusion openings (10, 60) are produced in the carrier (9, 59a, 59b, 59c). Process according to Claim 12, in which the extrusion openings (10, 60) are introduced into the carrier (9, 59a, 59b, 59c) as a final process step. Process for the production of regenerated cellulosic molded bodies (4), in which a spinning mass (2) containing cellulose is passed through a molding tool (1, 51) is extruded according to one of claims 1 to 11 and is precipitated in a spinning bath (5) in order to produce the shaped bodies (4). Process according to Claim 14, in which the spinning mass (2) contains a tertiary amine oxide in which the cellulose is dissolved and the spinning bath (5) has a mixture of water and tertiary amine oxide.

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