Classifications

• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D10/00—Physical treatment of artificial filaments or the like during manufacture, i.e. during a continuous production process before the filaments have been collected
  • D01D10/06—Washing or drying
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D13/00—Complete machines for producing artificial threads
  • D01D13/02—Elements of machines in combination
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/06—Wet spinning methods
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/12—Stretch-spinning methods
  • D01D5/16—Stretch-spinning methods using rollers, or like mechanical devices, e.g. snubbing pins
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D7/00—Collecting the newly-spun products
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
  • D01F2/02—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from solutions of cellulose in acids, bases or salts

Definitions

• the invention relates to a device for the post-treatment of solvent-spun cellulose fibers.
• NMMO N-methylmorpholine N-oxide
• Lyocell as a generic name has been recognized by the BISFA (Bureau for the Standardization of Rayon and Synthetic Fibers, Brussels) and in the USA (by the Federal Trade Commission).
• spinning solution typically cellulose concentrations 8-20% is extruded through an air gap into a coagulation bath, where solvent exchange takes place, resulting in the precipitation of the initially dissolved cellulose as thread-like products.
• Dry-jet-wet spinning as a lyocell process is used, for example, in US 4246221 A , US 4416698 A , WO 93/019230 A1 , WO 94/028218 A1 , WO 97/33020 A1 , WO 2002/012599 A1 , WO 2003/014436 A1 , WO 2003/057951 A1 , WO 2013/030399 A1 , WO 2013/030400 A1 , WO 2014/057022 A1 , WO 2020/043860 A1 , described.
• the Lyocell process typically uses tertiary amine oxides, such as N-methylmorpholine N-oxide (NMMO), or ionic solubilizers ("ionic liquids”) as solvents.
• NMMO N-methylmorpholine N-oxide
• ionic liquids ionic solubilizers
• lyocell filaments are usually a continuous process involving several steps, such as in EP 1500724 B1 described: (A) Dissolving cellulose in a solvent mixture, (B) Extruding the spinning solution through a spinneret, followed by passing through an air gap and then coagulating the spinning solution in a coagulation bath to obtain a multifilament (dry-jet-wet spinning), (C) Washing out the solvent through an aqueous water wash bath, (D) Continuously treating the multifilament through an oil treatment device and through a swirling nozzle, and (E) Drying and then winding.
• the post-processing of commercially usable cellulose filaments and yarns requires careful washing and drying, during which the forces acting on the tensile filaments and the washing and drying conditions are precisely controlled.
• Commercially usable cellulose filaments should be free of filament damage, homogeneous in structure and chemical composition, and easily post-processed (e.g., uniformly dyeable).
• the washing process in particular, is a costly procedure to recover the (expensive) solvent.
• the present invention relates to a device for solidifying and coiling cellulose multifilaments, comprising a Spinning plant (with an extrusion plant with at least 10 openings for forming filaments and a coagulation plant for solidifying the filaments) and a thread winder for winding the cellulose filaments, characterized in that the device contains no or only a partial washing plant for washing the cellulose filaments or for extracting a cellulose solvent from the cellulose filaments between the coagulation plant and the thread winder.
• the invention further relates to a method for the production and processing of cellulose filaments comprising a spinning process (dry-wet spinning process or wet spinning process) for the production of cellulose filaments, wherein the cellulose filaments contain cellulose solvents, optionally partial washing of the cellulose filaments or optionally partial extraction of a cellulose solvent from the cellulose filaments, whereby the solvent content of the cellulose filaments is reduced and the cellulose filaments remain moist, and winding of the washed and moist cellulose filaments.
• a spinning process dry-wet spinning process or wet spinning process
• the invention relates to a method for the production and processing of cellulose multifilaments, comprising forming at least 10 cellulose filaments and solidifying the at least 10 cellulose filaments in a coagulation unit, wherein the solidified cellulose filaments are moist and contain solvents of cellulose, and winding the moist, solvent-containing cellulose filaments.
• the invention also relates to a method for processing freshly spun cellulose multifilaments, wherein a cellulose multifilament comprises at least 10 cellulose filaments, comprising winding at least one solvent-containing cellulose multifilament onto a spool.
• the invention also relates to cellulose filaments obtainable according to the inventive method.
• the cellulose filaments may have been wound while moist and dried in the wound state.
• a cellulose filament may have periodic indentations, with the indentations occurring every 5 ⁇ m to 1000 pm.
• the periodic indentations may occur in groups of, for example, 10 or more, e.g., 10 to 1000 indentations.
• the invention relates to a cross-coil with at least one moist wound cellulose multifilament, wherein The cellulose multifilament comprises at least 10 cellulose filaments, wherein the cross-coil has a coil body as a support which is cylindrical, and the cellulose multifilament is wound onto the coil body with a laying angle of 5°-20° or with a cross angle of 10°-40°.
• preferred method features also correspond to properties or suitability of the apparatus or its corresponding components
• preferred apparatus features also correspond to means used in the method according to the invention.
• the cross-coil with wound cellulose filaments and the cellulose filament are products of the method. All preferred features are combinable with one another unless explicitly excluded. All method features, including those mentioned above, are combinable with one another. All apparatus features, including those mentioned above, are combinable with one another.
• a spinning unit (1) for cellulose filaments (1d) is shown, comprising an extrusion plate (1d) with extrusion openings and a coagulation bath (1c).
• a deflecting roller (2) for deflecting cellulose filaments produced in the spinning unit is also shown.
• the cellulose filaments are guided through an optional partial washing unit (3) and, via a further deflection roller (5), into the filament winder (4).
• the cellulose filaments are wound onto a spool (4a).
• a spool with wound cellulose filaments (4b) is shown.
• the cellulose filaments can be wound crosswise.
• a changing filament guide (4c) can be provided to position the cellulose filaments during the winding process.
• a separate spool washer (6) for washing a spool with wound cellulose filaments can be provided.
• the spools with cellulose filaments are made of taken to the thread winder (4) and brought to the bobbin washer (6).
• FIG. 3 An SEM image shows several cellulose filaments produced according to the invention. Indentations spaced 100 pm apart are visible on the filaments. These were created by the inventive method (in particular, the crossed winding in a moist, solvent-containing state, followed by washing and drying).
• the invention relates to a device for the post-treatment of solvent-spun cellulose filaments, in particular cellulose multifilaments or cellulose filament yarns.
• the post-treatment comprises the winding of solvent-containing cellulose filaments.
• Solvent-spun cellulose filaments are produced in a dry-wet spinning plant/process or in a wet spinning plant/process and still contain solvents from cellulose immediately after production (as mentioned in the background, tertiary amine oxides, in particular NMMO, or ionic liquids).
• a dry-wet spinning process typically includes the following steps: i) Shaping the cellulose solution: This can be done, for example, by extruding the cellulose solution through extrusion dies.
• An extrusion machine usually has a plate with these extrusion dies.
• the size of the extrusion dies can influence the diameter of the formed cellulose filaments (another factor influencing the diameter is the stretching of the cellulose filaments); ii) Treating the shaped cellulose solution in a gas gap: Here, stretching of the cellulose solution can occur; and iii) Consolidating the cellulose solution into cellulose bodies (especially cellulose filaments, also called cellulose threads): Consolidation usually takes place in a coagulation unit—here, the cellulose solution is introduced into a fluid that removes cellulose solvent from the cellulose solution, causing it to solidify and form the cellulose filaments. The removal of cellulose solvent is carried out in the coagulation plant.
• a dry-wet spinning plant can include i) an extrusion device, ii) a gas gap, and iii) a coagulation bath.
• a gas gap iii
• a coagulation bath iiii
• cellulose filaments are produced in a similar manner using a wet spinning system.
• the shaping of the cellulose solution is carried out in the same way as in the wet-dry process, particularly by extrusion. Instead of a gas gap, the shaped cellulose solution is solidified immediately in step iii). Solidification occurs as in the wet-dry process, except for the absence of a gas gap, especially using a coagulation system such as a coagulation bath.
• Wet spinning and wet-dry spinning processes are used, for example, in Azimi et al., Cellulose (2022) 29:3079–3129 , US 2022/0112628 A1 and US 11,208,739 described.
• a funnel-shaped coagulation bath in which the cellulose filaments are passed through a funnel-shaped bath and drawn off at the bottom through a hole in the funnel base
• US 5639484 A Both configurations are possible and are shown schematically in Fig. 1 and Fig. 2 Roughly illustrated.
• the cellulose filaments After the coagulation bath in the device/coagulation using the dry-wet process, the cellulose filaments are solid and no longer in a liquid state.
• the optional washing afterwards is therefore not coagulation, but rather serves to wash out some of the cellulose solvent. This can alter the plasticity of the cellulose filament and thus improve its ability to be coiled while wet (i.e., without drying). Washing can be used to extract cellulose solvents from the cellulose filaments.
• the invention relates in particular to the treatment of cellulose multifilaments produced in a spinning process or spinning plant, specifically immediately after their production, where the cellulose filaments of the multifilaments still contain solvent, i.e., the cellulose filaments are already coagulated but still contain significant amounts of solvent, which affects the plasticity of the cellulose filaments.
• the solvent is removed from the cellulose filaments as quickly as possible so that expensive solvent is recovered and finished, further-processable cellulose filaments are obtained.
• the solvent-containing cellulose filaments are wound up. In the wound state, e.g., on a spool, the solvent-containing threads can be washed out much more efficiently.
• a spool is also referred to as a tube or bobbin.
• the invention enabled the elongation of cellulose filaments to be increased by up to 50%, which significantly facilitates the further processing of the produced filaments into end-customer products. Secondly, the strength of the cellulose filaments could also be increased by up to 20%, which is likewise advantageous for further processing.
• cellulose multifilaments are typically carried out industrially to obtain filament bundles or yarns that are desirable on the market, i.e., those with sufficient strength and flexibility.
• multifilaments must be washed (i.e., solvents completely removed) and dried quickly after production before being wound up.
• the aforementioned production description is common for the manufacture of staple or continuous filaments.
• the multifilament is wound up while still moist and containing solvent. Due to the plasticity of moist, solvent-containing multifilaments, this can lead to deformation.
• the cellulose multifilament preferably consists of 10 or more, 20 or more, 30 or more, particularly preferably 50 or more, or 75 or more, or even more preferably 100 or more, single cellulose filaments. Accordingly, the extrusion system has 10 or more, 20 or more, 30 or more, particularly preferably 50 or more, or 75 or more, or even more preferably 100 or more extrusion openings.
• the invention relates to a device for solidifying and winding threads, comprising a spinning unit for cellulose filaments, a deflecting roller for deflecting cellulose filaments produced in the spinning unit, and a thread winder for winding the cellulose filaments, wherein the device includes no or only a partial washing unit for washing the cellulose filaments or for extracting the cellulose solvent from the cellulose filaments between the spinning unit and the thread winder.
• the invention also relates to a device for solidifying and winding cellulose multifilaments, comprising an extrusion unit with at least 10 openings (nozzle openings) for forming filaments, a coagulation unit for solidifying the filaments, and a thread winder for winding the cellulose filaments, characterized in that the device includes no or only a partial washing unit for washing the cellulose filaments between the coagulation unit and the thread winder.
• the cellulose filament is still damp and contains solvents when it reaches the thread winder.
• Solvent refers to solvents from the cellulose.
• a partial washing system for example, can only wash out solvents from the outer areas of the cellulose filaments. This leads to a reduction in the plasticity of these outer areas.
• Such partial washing can be limited by the length of the partial washing system.
• the length of the partial washing system can be specified.
• the partial washing system can have a maximum length of 5 m, preferably a maximum of 3 m, or even a maximum of 2 m. Particularly preferred is a partial washing system with a maximum length of only 1 m.
• the length refers to the section over which a cellulose filament is treated with a washing liquid (e.g., water) in the partial washing system.
• a washing liquid e.g., water
• this section includes the structural measures for the treatment, such as a washing bath (bath length) or, in the case of spraying, the length over which spray nozzles are arranged.
• the washing medium in the partial washing system can contain solvents, or the process can involve partial washing with a solvent-containing medium.
• the device may optionally include one, several, or all of the following elements, preferably in this order in the production direction: spinning mass supply, spinning pump, heat exchanger, nozzle block with sieve, distribution plate and nozzle, gas gap, blown air supply into the gas gap, blown air exhaust from the gas gap, blown air guide plates at the gas gap, contact precipitation, deflector, partial washing unit, deflector (roller), yarn winder.
• the yarn winder may be configured with multiple winding stations.
• the invention further relates to a method for the production and processing of cellulose filaments, comprising spinning processes for the production of cellulose filaments, wherein the cellulose filaments contain solvents of cellulose, no or partial washing of the cellulose filaments, whereby the solvent content of the cellulose filaments is reduced, and the cellulose filaments remain moist and solvent-containing, and winding of the moist, solvent-containing cellulose filaments.
• the invention further relates to a method for the production and processing of cellulose multifilaments, comprising forming at least 10 cellulose filaments and solidifying the at least 10 cellulose filaments in a coagulation unit, wherein the solidified cellulose filaments are moist and contain solvents of cellulose, and winding of the moist, solvent-containing cellulose filaments.
• the method includes partial washing of the cellulose filaments, whereby the solvent content of the cellulose filaments is reduced but not completely removed, and the cellulose filaments remain moist. Partial washing can remove the solvent-containing substances.
• Cellulose filaments have a core area with a higher solvent concentration than an outer area. Washing the multifilaments on the spool has proven particularly efficient, especially compared to conventional washing in the production line, such as in... WO 2020/136109 A1 or WO 2021/105275 A1 described or on a roll as in EP 3812489 A1 described. According to the invention, such deflection pulleys are preferably avoided.
• the invention also relates to a method for processing freshly spun cellulose filaments, in particular cellulose multifilaments, wherein solvent-containing cellulose filaments are wound up, especially on a spool.
• the solvent-containing cellulose filaments can have a core region with a higher solvent concentration than in a peripheral region of the cellulose filaments.
• the freshly spun cellulose filaments originate from a spinning process. Subsequently, no or only partial washing of the already solidified cellulose filaments can take place, as mentioned above. Peripheral region and core region refer to the filament cross-section.
• the thread cross-section is usually round, but can also have other shapes, depending on the shape of the extrusion openings in the wet-dry process.
• the thread cross-section is circular or elliptical.
• the cellulose solution is forced (extruded) through the extrusion dies at a specific extrusion speed.
• the cellulose solution is a highly viscous liquid and can withstand certain tensile forces. This is utilized for the aforementioned stretching in the gas gap during the dry-wet spinning process. For stretching, the cellulose filaments are drawn off at a certain speed. This tensile force on the (solid) cellulose filaments continues to extrude in both the dry-wet and wet spinning processes, and in the dry-wet process, it also causes the cellulose solution to stretch in the gas gap.
• the draw-off speed is achieved not only by a draw-off device but also continuously via driven rollers.
• the cellulose filaments also called cellulose threads
• the cellulose fibers would be subjected to strong forces multiple times during the process. These forces would not be balanced, especially by driven rollers.
• driven rollers For example, in US20130101843A1 As shown, in washing systems that completely remove cellulose solvents, and in drying systems, the cellulose fibers run over numerous rollers. If these rollers were not driven, the forces exerted on the cellulose fibers would be too strong and would cause fiber breakage. To prevent this, in the conventional lyocell process, guide rollers are driven.
• the cellulose solution for extrusion is preferably a mixture of cellulose, solvent, and water.
• An example of a spinning solution is: cellulose: 12.9%; solvent, e.g., NMMO: 76.3%; water: 10.8% (all percentages by weight).
• the number of deflection devices, in particular the deflection rollers is minimized because no or only a simplified partial washing and no drying are carried out before winding/before the yarn winder. Due to the small number of deflection devices/deflection rollers, it is not necessary to drive the deflection devices/deflection rollers, since the small number also results in only minimal forces being exerted on the cellulose filaments.
• the yarn winder can provide the take-off speed for the spinning unit, or a yarn winder can be used in the method to take off the cellulose filaments in the spinning process, particularly from the coagulation unit.
• This can be done directly or indirectly via one or more intermediate filament deflectors (also called deflection devices or deflectors).
• the number of deflectors, such as deflection rollers, between the yarn winder and the spinning unit is limited; for example, a maximum of 5 deflectors, such as deflection rollers, or a maximum of 4, 3, or 2 deflectors, such as deflection rollers, can be provided.
• the number of deflectors in the spinning unit is also preferably limited.
• the spinning machine can have 0, 1 or 2 deflectors, preferably deflection rollers, preferably 0 or 1.
• the entire inventive device has 0, 1, 2, 3, 4, 5, or 6 deflectors, in particular deflection rollers, preferably 1, 2, 3 or 4.
• the wet-dry process is used.
• the thread winder can then supply or control the take-off speed for stretching in the gas gap.
• one or more, preferably two, three, four, five, or all, of the deflection rollers are rotatably mounted and/or driven without a motor. Due to the free rotation and the absence of a motor, the rollers exert no pulling force on the cellulose filaments. Frictional forces on the threads are minimized by the rotatable mounting. Preferably, there is no motorized deflection roller between the dry/wet spinning unit and the thread winder. Motorized deflection rollers can cause filament defects in the cellulose filaments, especially in multifilaments, and are therefore preferably avoided. Rotatably mounted deflection rollers rotate with the cellulose filaments attached to them, preferably without slippage.
• the cellulose filaments are deflected by a deflector, preferably a deflection roller, which is preferably not motorized.
• a deflector preferably a deflection roller
• Deflectors also called deflection devices, can be deflection rollers or deflection edges. Deflection rollers are preferred. Preferably, no deflection edges are used.
• the cellulose filaments are deflected by a deflector (deflection device), preferably a deflection roller, before winding.
• this deflection roller is not motorized or rotatably mounted. This allows the cellulose filaments to be deflected in their guiding direction towards the yarn winder.
• Deflection pulleys preferably have an outer diameter of 0.4 mm to 4 cm, preferably from 0.6 mm to 3 cm.
• the winding process creates tension on the cellulose filaments, which continues until the spinning process, particularly during consolidation, and determines the unwinding speed of the cellulose filaments during the spinning process, especially after consolidation, preferably the unwinding speed from the coagulation unit.
• This continuation of tension is achieved by the rotatably mounted or non-motorized deflection rollers – and their small number (maximum partial washing, no drying/no dryer).
• a partial washer can be designed very simply. In particular, the partial washer avoids separate deflection elements such as rollers.
• the cellulose filament can be guided under a water shower.
• the cellulose filaments are drawn off from the spinning process, preferably from a wet-dry process, and particularly preferably after solidification or coagulation, at a draw-off speed of 100 m/min to 500 m/min.
• the extrusion speed is lower and can be, for example, 10–150 m/min. Higher draw-off speeds result from the stretching process.
• the formed cellulose solution can be stretched/stretched in the air gap to 2-20 times, preferably 3-15 times, in particular to 4-10 times, its original length (length immediately after extrusion).
• the partial washing system has one, two, or more washing channels.
• One washing channel can be positioned for washing a cellulose multifilament. If several multifilaments are produced in parallel, preferably one washing channel is provided for each multifilament. In the washing channels, the multifilaments are washed to remove some of the cellulose solvent.
• the partial washing system has two or more washing channels, and two washing channels are positioned at an angle of 0° to 150°, preferably 5° to 50°, to each other.
• the angle is the angle between the washing channel axes of the two washing channels, enclosed by washing channel axes defined along the multifilaments.
• the angle opens in the production direction, i.e., away from the coagulation unit and towards the yarn winder.
• the partial washing unit is positioned with a gradient of 0% to 373%, more preferably 5% to 100%.
• the gradient is essentially downwards in the production direction, i.e., in the direction from the coagulation bath to the filament winder or in the filament take-off direction. Washing fluid can thus flow off by gravity in the filament take-off direction, i.e., in a co-current flow.
• the partial washing system has two or more washing channels, one of which is positioned for washing a cellulose multifilament.
• the two or more washing channels can be positioned at different gradients relative to each other.
• the cellulose filaments are formed using a cellulose solution containing a cellulose solvent at a concentration of 60% to 85%.
• the formed cellulose filaments are treated in the coagulation unit with a coagulation fluid containing a cellulose solvent at a concentration of 0% to 30%, preferably 5% to 25%.
• the cellulose filaments have a cellulose solvent content of 30% to 60%, preferably 40% to 55% (all wt%) after coagulation.
• the cellulose filaments are partially washed until the cellulose solvent content is reduced to 10% to 40%, preferably 20% to 30% (all wt%).
• the proportion of cellulose solvent is continuously reduced.
• a cellulose solution is present, which is extruded and shaped. This is typically done at high temperatures, e.g., above 75°C, or at room temperature (e.g., with ionic liquids). The temperature depends on the solvent.
• This solution solidifies/coagulates by reducing the proportion of cellulose solvent and the temperature.
• the proportion is then further reduced by partial washing.
• the cellulose solvent is only completely removed after the material is wound/rewound into a compact, coiled form, e.g., onto a spool.
• the filament winder incorporates a changeover filament guide.
• a changeover filament guide is preferably suitable for controlling the lay angle of the filament winding.
• the lay angle is the angle of the filaments on the spool.
• the winding is cross-wound and inclined.
• a deflector or deflection device before the changeover filament guide can, for example, also be designed and installed in a non-straight, slightly curved, or specially shaped configuration to compensate for variations in path length.
• a deflector or deflection device after the changeover filament guide can be used to press cellulose filament onto a spool on which the cellulose filaments are wound.
• This pressure can be, for example, 3 to 30 N.
• the changeover filament guide can direct the cellulose filament to different positions within the filament winder. This allows the filament to be guided and deposited in different positions on a spool. This enables winding patterns to be set with a selected density via the filament winder's rotation axis.
• the cellulose filament is wound crosswise onto a spool. This crosswise winding can be accomplished by the filament guide.
• the filament winder has a spool for winding the cellulose filaments.
• the filament guide is essentially a cellulose filament guide and is preferably operated by a motor, e.g., a stepper motor, linear guide drive, or motors that enable linear movement of the filament guide based on a rotary motion.
• the drive of the filament guide can also be magnetically coupled or achieved through the use of various mechanisms.
• the moist cellulose filament is guided linearly along an axis by the filament guide through its back-and-forth movement.
• a deflector e.g., a pressure roller
• the formed moist cellulose coagulate in the form of a single filament or a strand of filament (a strand of filament can consist of several individual filaments, e.g., 1000 or more), is wound onto the motor-driven spool body to form a moist cellulose filament spool.
• the filament winder can simultaneously serve as a take-up device after the spinning process to adjust the desired individual or total filament thickness (drawing).
• a variable filament guide on a filament winder for filaments with adjustable filament guide stroke and stepless, collective adjustment of the spool flank angle is used, for example, in US 3730448 A described.
• the thread winder has a spool for winding the cellulose filaments, preferably the spool being driven by a motor.
• the spool is clamped.
• the spool can wind the cellulose filaments onto a bobbin by rotating the spool around a bobbin axis.
• the spool is rotationally symmetrical with respect to its circumference and can be cylindrical or conical.
• the bobbin can also have holes or perforations, which need not be rotationally symmetrical, but may be.
• the winding speed can be automatically controlled depending on the set take-off speed, as well as the extrudate (extrusion openings) and spool diameter. To create an ideal winding pattern, the tension between take-off and winding can be dynamically adjusted. After the winding process, the spool, along with the cellulose filament, can be removed and used or stored.
• the cellulose filaments preferably have a solvent concentration of 10% to 40%, preferably 20% to 35% (all weight %), when wound up, e.g. after partial washing.
• the cellulose filaments are wound with a packing density of 0.8 g/ cm3 to 1.3 g/ cm3 of moist cellulose filaments and/or the cellulose filaments are wound with a packing density of 0.2 g/ cm3 to 0.7 g/ cm3 based on dried cellulose filaments.
• the packing density can be determined by the thread guidance on the reel; for example, a cross-winding pattern can be used to adjust the spacing of the cellulose filament windings.
• a variable thread guide is preferably used. This can determine the position of the The density of the cellulose filaments wound onto a spool is determined according to the invention.
• the cellulose filament thread can be wound such that the adjacent threads are separated from one another and formed with uniform tension into a continuous cellulose filament spool body.
• the density of the filaments on a pack is preferably adjusted to 0.3 to 0.6 g/ cm3 of spool volume.
• the packing density is achieved by appropriately selecting the winding parameters.
• the main parameters include the winding method and the angle of the laid thread.
• the "distributed wind” or "random winding” technique has proven suitable.
• the cross angle of the filament selected for this is preferably in the range of 20° to 28°.
• the cellulose filaments are wound cylindrically or conically at the ends of the spool.
• the tangential pull in the crossed winding can, for example, have a value of 3 to 500 cN, preferably 5 to 50 cN, and more preferably between 10 and 20 cN.
• Individual cellulose filament windings are not laid onto the spool at a constant winding ratio (spool revolutions per double stroke of the thread guide), but rather at a constant angle (laying angle).
• This angle is defined by measuring it using a surface projection of the spool between a straight line that intersects the spool axis orthogonally and the path of the cellulose filament.
• This winding technique lays the cellulose filament onto the spool particularly gently and, above all, loosely, resulting in a particularly low density of the generated thread cake. This, in turn, makes the cake especially easy to wash in subsequent laundry. Furthermore, this method allows the cellulose filament to cross over previously laid cellulose filaments, creating a cross-winding.
• the cross-winding gives the spool high mechanical strength and is particularly suitable for winding onto spool bodies without side walls.
• the cellulose filaments are wound at a laying angle of 5°–20°, more preferably 10°–14°.
• the double laying angle then corresponds to the cross angle.
• different filament layers relative to each other.
• the angle between the filaments can be 10°–40°, preferably 15°–30°.
• the invention also relates to a cross-wound spool with at least one wet-wound cellulose multifilament, wherein the cellulose multifilament comprises at least 10 cellulose filaments, the cross-wound spool having a cylindrical spool body as a support, and the cellulose multifilament being wound onto the spool body with a lay-up angle of 4°–20° or with a cross-angle of 10°–40°.
• the cellulose multifilament can be dried and present on the spool in a dried state.
• the lay-up angle is formed by the normal to the cylindrical axis of the spool body and the laid-up multifilaments, at least in a central part of the spool. In the outer regions of the spool, the filaments can be wound at a different angle for deflection and retraction.
• the coil winding can be carried out in stages.
• An initial base winding (e.g., in a start-up process) can be applied, which is wound with a slightly different winding angle.
• This initial winding is placed on the empty coil former and serves the purpose of building the winding into the ideal cylindrical final shape.
• a constant winding angle is maintained, as described above.
• the winding angle is the angle between the cellulose filament and the perpendicular to the coil axis (also called the axis of rotation).
• the cellulose filaments are wound in a start-up process (base winding) and a subsequent main winding process, wherein the winding angles in the start-up process and the main winding process differ from each other by 0.5° to 10°, preferably by 0.5° to 3°.
• the bobbin winds more efficiently if it is not perfectly cylindrical, but rather has angled edges at the ends.
• the edge angle is used for this purpose. Winding at an edge angle of less than 90°, for example, between 60° and 85°, results in a particularly gentle winding of the thread's turning points, as these points do not overlap but are instead pushed further and further towards the center of the bobbin as it grows.
• the packing density of the spool is defined by the mass of the cellulose filaments on the spool in the dry state divided by the enclosing volume of the cellulose filaments on the spool.
• the thread winder can be a device for receiving and depositing moist, solvent-containing cellulose filaments.
• the device can be further supplemented by a separate spool washer.
• the separate spool washer is used for washing cellulose filaments wound on a spool.
• the wound multifilaments are washed on the spool, preferably with a washing liquid flow rate of 1000 to 10000 liters per minute and/or 2 to 50 liters per minute per kilogram of dry cellulose filament.
• the cellulose filaments are post-treated after winding by washing, rinsing, bleaching, dyeing, cross-linking, and drying processes. This post-treatment of the cellulose filaments takes place in the wound state, particularly on a spool.
• the cellulose filaments are preferably wound at a laying angle of 5°–20°, more preferably 10°–20°.
• the thread winder can be speed-controlled or tension-controlled, with the device preferably having a dancer arm. With speed control, the winding speed is adjusted to achieve the desired take-off speed.
• a take-off mechanism can be installed upstream of the thread winder to determine the take-off speed.
• the filament tension can be kept constant by a dancer arm (optionally with a dancer arm roller). This compensates for tension variations that would occur due to the movement of the changing thread guide.
• the cellulose filaments can be wound onto a spool, preferably mechanically clamped. After one spool is completely wound, another spool can receive the wound cellulose filaments.
• the thread winder can have a spool changer for switching between spools.
• a spool changer can, for example, have two or more spool holders.
• the spool holders contain spools, one of which holds cellulose filaments. on ("active spool carriers" or "active spool”).
• the active spool carrier or active spool can be associated with the changing thread guide.
• One or more spool carriers can be provided for quick repositioning to the position of the active spool carrier.
• Such provided spools are also called standby spools.
• the spool carriers can be arranged on a rotatable support, e.g., a disc. Rotating the support changes the position of the spool carriers.
• Spool carriers are, for example, bolts on which the clamped spools can rotate for winding.
• the device has one or more standby spools, particularly in conjunction with the winder.
• Standby spools are in a position without filament feed/without changeover thread guide.
• Standby spools can be provided for switching to the position of a fully wound spool.
• the device has a spool-changing system that can change the position of two or more spools, whereby one spool is moved into a winding position and/or one spool is moved away from a winding position.
• the device has a spool transfer system suitable for changing spools by linear and/or rotary motion.
• spools can be changed by linear and/or rotary motion.
• a standby spool is positioned next to a wound spool by rotation, so that a changeover filament guide begins to wind cellulose filaments onto the standby spool without interruption. This transfers the cellulose filament from one spool to the other.
• the cellulose filament transferred from the previously wound spool to the standby spool can be cut during the filament transfer between the spools.
• the device can have a cutting device.
• the fully wound spool can be moved by a linear motion to allow for a smaller design of the winding device.
• a wound cellulose filament packing preferably has a circumference of 60 mm to 600 mm; preferably, the moist spool circumference is in the range of 100–300 mm; or 150–250 mm.
• the cellulose filament spool bodies produced according to the invention preferably have a length of 50 mm to 500 mm. While different winding conditions may be suitable for different filament types, it has been found that the following is ideal for the production of solvent-impregnated, precision-wound spools with a density of 0.3 to 0.5 g/ cm3 (based on dry cellulose filaments), and/or with a minimum circumference of at least 120 mm and/or a cellulose filament pack length of 120 to 160 mm.
• primary wound cellulose filament spool refers to the spool/filaments wound directly after production and for the first time. These filaments from the primary wound cellulose filament spool can be unwound and rewound. These are referred to as “secondary wound cellulose filament spools" (or “secondary windings"). These filaments of the secondary wound cellulose filament spool can be unwound and rewound.
• tertiary wound cellulose filament spool or tertiary winding.
• Various treatment steps can be carried out between these windings, such as solvent extraction (washing) – this time complete or nearly complete – various treatments, and drying.
• the device further comprises a spool washer.
• the spool washer is used for washing cellulose filaments wound on a spool.
• the method according to the invention preferably includes the step of washing wound cellulose filaments, particularly preferably cellulose filaments wound on a spool. During this washing process, cellulose solvent is removed from the cellulose filaments as completely as possible, particularly by displacement during washing.
• the washing liquid is preferably an aqueous fluid, especially water. Washing the wound cellulose filaments can be designed to be very flexible with regard to temperature, pressure, washing medium flow rate (usually water or aqueous liquid), and time. This is an advantage of the method according to the invention, since the process parameters during unwinding, as in conventional continuous washing, can be adjusted as needed. US 2013/0101843 A1 described, need not be taken into account. In these continuous When working directly on the extracted cellulose filament, the thread must still be handled very carefully, as the thread under tension can easily develop filament defects such as cracks.
• the cellulose filaments on the spools are moist but no longer contain solvents, or only a small amount (e.g., less than 0.1% by weight solvent).
• These moist, coiled cellulose filaments can be further processed or dried.
• the moist cellulose filaments are treated before drying, for example, by washing, anointing, crosslinking, bleaching, and/or dyeing. This treatment is carried out while the filaments are coiled, e.g., on a (cross-)spool. Anointing while coiled can be performed, for example, in a spool washer or during mechanical dewatering. Such treatment steps are more efficient on moist cellulose filaments that have not been previously dried.
• the device according to the invention can have corresponding treatment chambers for bleaching, dyeing, impregnating, and crosslinking.
• a spool dryer e.g., a high-frequency heater, microwave dryer, hot air dryer, or drying chamber. These chambers are specifically designed for spools, i.e., a spool holder may be included.
• the wound cellulose filaments particularly those on a spool, can be treated according to the process steps described above.
• the moist wound and/or wound cellulose filaments have a relative humidity of 50% to 170%, more preferably 100% to 140% (all weight percent).
• the solvent-containing cellulose filaments, wound into yarn spools, are preferably subjected to a further post-treatment step after winding.
• This post-treatment step can consist of subjecting the moist yarn spool to further swelling in a solvent bath.
• Solvent baths can be, for example, dilute amine oxide solutions or ionic liquids.
• the resulting yarn spools can also be immersed in other solvent baths. which exert an accelerated or delayed crystallization effect on the cellulose filaments.
• Cellulose can be subjected to substitution reactions.
• the aim of these reactions on freshly spun, moist, and highly reactive cellulose filaments is to produce products with modified properties. This can broaden the range of applications for cellulose filaments. Esterification, etherification, and grafting reactions are all possible substitution reactions.
• the wound multifilaments on the spool are dewatered, preferably by mechanical dewatering, e.g., centrifugation, and/or drying by heat and/or vacuum.
• mechanical dewatering is carried out to a water content of 30%–70% (by weight) followed by drying. Drying, including partial drying, can be carried out using convective, contact, radiation, electric, high-frequency, or microwave drying methods.
• the cellulose filaments can be rewound onto a different spool. This improves the packing density after water loss. After drying, the filaments can be subjected to heat fixation.
• a spool with crossed wound cellulose filaments is also called a cross-wound spool.
• the descriptions herein, and especially those that follow, relate to spools and, in particular, to the cross-wound spool.
• the laying angle of the filaments is preferably 5°–20°, as described above. Preferably, this results in a cross angle of 10°–40° for different filament layers.
• the cellulose filaments may contain cellulose solvents.
• a cross-wound spool according to the invention can be formed and/or processed according to a method according to the invention, e.g., washed or dried.
• the spools preferably have a perforated spool body.
• the spool body can have a multitude of holes through which or into which washing liquid, treatment liquid, or a drying gas can pass. This allows the cellulose filaments wound on the spool body to be treated continuously from both the outside and the inside (via the perforations/holes).
• the multitude can, for example, form 30 or more, or 50 or more holes. This can be adjusted according to the size of the
• the bobbin body can be scaled.
• the bobbin bodies can also consist of surface-closed hollow cylinder elements, perforated metal or plastic cores, or spring-like bobbins onto which the continuously formed thread is wound.
• the bobbin body is made of polypropylene.
• the bobbin body is a hollow cylinder, preferably with a wall thickness of 0.5 mm to 5 mm.
• the bobbin body is perforated, preferably with openings that cover 10% to 60%, preferably 20% to 50% of the bobbin surface.
• the cellulose filaments on the spool are wound with a packing density corresponding to 20-60% (volume %), preferably 25-35% (volume %), of dry cellulose filaments.
• the volume refers to the volume occupied by the cellulose filaments and the spaces between the filaments.
• An enclosing volume around the filaments can also be defined.
• the coil former has a modulus of elasticity of 1200 MPa to 1300 MPa and/or a tensile strength of 33 to 37 MPa measured according to ISO 527-2, and/or withstands a compressive force of 450 N to 550 N according to EN 12080.
• the coil former is made of polypropylene.
• the solvent for cellulose is a tertiary amine oxide, preferably N-methylmorpholine N-oxide (NMMO), or an ionic solvent, preferably with an ammonium, pyrimidium, or imidazolium cation, particularly preferably 1,3-dialkylimidazolium, especially preferably 1,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1-methyl-3-propylimidazolium, 1-isopropyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-methyl-3-pentylimidazolium, 1-hexyl-3-methylimidazolium, 1-heptyl-3-methylimidazolium, 1-methyl-3-octylimidazolium, 1-decyl-3-methylimidazolium, 1-methyl-3-benzylimidazolium, 1-methyl-3-(3-phenylpropyl)imidazolium
• the ions can be coupled with common counterions (anions) such as fluoride, chloride, bromide, thiocyanate, dicyanamide, nitrate, methyl phosphate, acetate, formate, propionate, benzoate, thioglycolate, methyl sulfate, and hydrogen sulfate.
• common counterions anions
• Cellulose solvents are described, for example, in Négrier et al. (DOI:10.1039/d2su00084a). Elsayed et al. (Cellulose 28: 533-547, (2021 )), Azimi et al. (Cellulose 29: 3079-3129, (2022 )), Swatloski et al. (J. Am. Chem.
• ionic liquids described therein can be used to prepare cellulose solutions and for the production of cellulose fibers according to the invention.
• 1-Butyl-3-methylimidazolium (Bmim) or 1-Ethyl-3-methylimidazolium (Emim) are preferred.
• high-purity ionic liquids so-called CBILS® Carbonate Based Ionic Liquids, such as 1,3-dialkylimidazolium, can also be used as solvents.
• the coagulation liquid can contain water, in particular a mixture of water and a solvent for cellulose.
• cellulose solutions formed can also be processed into cellulose filaments using the device according to the invention.
• the cellulose filaments obtained by spinning are preferably a multifilament or bundled together, e.g., 10 or more, 30 or more, 50 or more, 100 or more, or 200 or more. These cellulose filaments can be processed together as yarn in such bundles. For this purpose, the cellulose filaments are produced in parallel.
• the extrusion device can have the same number of extrusion openings as the number of filaments produced in parallel, e.g., 10 or more, 30 or more, 50 or more, or 100 or more. Parallel spinning/extrusion is for example in WO 94/028218 A1 described.
• the invention further relates to a cellulose filament which is wound while moist and dried in the wound state.
• the invention also relates to a cellulose filament which can have periodic indentations, with the indentations occurring every 5 ⁇ m to 1000 pm.
• the periodic indentations can occur, for example, 100 times or more, 1000 times or more, or 10,000 times or more.
• Such cellulose filaments are obtainable according to the process of the invention.
• the cellulose filament can be present in a yarn of 10 or more, 30 or more, or 50 or more cellulose filaments, e.g., 100 or more cellulose filaments (multifilament).
• the cellulose filament according to the invention has a different structure than continuously produced cellulose filaments that are immediately washed and dried.
• the cellulose Due to the winding in a moist, solvent-containing state, the cellulose exhibits a different, slower crystallization or solidification behavior. According to the invention, the cellulose has an amorphous structure. Furthermore, plastic deformation is noticeable during cross-winding, which is why the filament can have indentations every 5 ⁇ m to 1000 pm, preferably every 10 ⁇ m to 500 pm, and particularly preferably every 30 pm to 120 pm. The indentations can be present in one area, alongside other areas with fewer indentations. The area with indentations corresponds to the central part of the spool with the cross-winding. In the outer region of the spool, filaments are deflected, and fewer indentations may be present in corresponding areas on the filament.
• An area with periodic indentations can, for example, comprise 10, 20, or 30 indentations. It has been found that the surface of the primarily wound, coiled, and swollen cellulose filaments (moist and containing solvents) is modified by the layered cross-winding of the cellulose filaments. The windings of different layers of moist cellulose filaments intersect, therefore only touching at isolated points, and modify the surfaces of the swollen fiber mass through mutual impressions.
• the induced plastic deformation of moist cellulose fibers refers to the irreversible change in the shape of the extruded cellulose material under the influence of external forces during primary winding. An initial plastic deformation of the cellulose fibers remains as a permanent change. This is achieved by the corresponding arrangement of their internal structures, in particular the crystal structures of the precipitated regenerated cellulose.
• An indentation can, for example, be 3%–30% of the diameter, preferably 5%–20% or 8%–15%.
• the moist, solvent-containing cellulose filament is wound up to a length of at least 50 m.
• the length is at least 100 m, more preferably 100 m to 5 km, and more preferably 200 m to 2.5 km, e.g., 300 m to 1.5 km.
• a cellulose filament produced according to the invention preferably has a fineness of 0.5 dtex to 10 dtex, more preferably 0.8 dtex to 5 dtex, and more preferably about 1-2 dtex.
• the overall fineness is specified.
• a bundle (or yarn) of 100 filaments, each with a fineness of 1 dtex has a fineness of 100 dtex (100 ⁇ 1 dtex).
• the fineness of a single filament (individual fiber) is preferably 0.5 dtex to 7 dtex, more preferably 0.8 dtex to 6 dtex.
• bundles with a fineness of 20 dtex to 3000 dtex are wound up, according to the invention, in a moist state.
• Dtex and further filament specifications are in accordance with BISFA (Terminology of Man-Made Fibres).
• a cellulose filament has a filament thickness of 4 pm to 30 pm, particularly preferably 7 pm to 25 ⁇ m, even more preferably 9 pm to 20 ⁇ m, and especially preferably 11 pm to 15 ⁇ m.
• Such threads are fine enough for applications in the textile industry and are also well-suited for processing in the apparatus according to the invention in the field of technical applications.
• the cellulose filaments produced according to the invention also have a higher strength (at the same thickness or fineness) of about 20%. This allows for the production of finer threads according to the invention (with comparable strength).
• a very bright (white) cellulose filament product could be produced using the process according to the invention, since the washing process carried out after the primary winding can be designed to be very efficient and gentle on the fibers, and the solvent can be completely removed from the fibers. This counteracts yellowing, so that no subsequent bleaching steps are necessary. The result is that the resulting cellulose fibers have improved mechanical properties, such as elongation and strength, an improved degree of whiteness, and thus improved dyeing properties. Likewise, the process This makes it more environmentally friendly than alternative fiber filament manufacturing processes, which require a bleaching step.
• the invention thus also relates to a cellulose filament which was wound while wet and dried in the wound state.
• the cellulose filament has at least 10 periodic indentations in a given area, wherein the indentations are present every 5 ⁇ m to 1000 pm in that area.
• the cellulose filament has a degree of crystallinity of 40%-50%, more preferably 41%-49%, or 42%-48%, or 43%-47%, or 44%-46%, preferably about 45%.
• the orientation parameter OG(004) is below 0.93 and the integral orientation parameter of the cellulose filament OGI, which can be derived from this, is in the range between 64% and 78%.
• the inventive method for producing the cellulose filaments yielded filaments with reduced Hermann orientation factors. This indicates a less pronounced alignment of the cellulose fibers in a specific direction, or, conversely, the less pronounced alignment results in a more random distribution and orientation of the cellulose structure within the filaments.
• the orientation of the cellulose filaments could be influenced by the inventive method.
• the quality and performance of the produced cellulose filaments are closely related to mechanical properties such as tensile strength, elongation, and stainability.
• the cellulose filaments produced according to the invention had orientation factors below 0.96.
• the cellulose filaments have an orientation factor of less than 0.965, preferably 0.963 or less, more preferably 0.961 or less, even more preferably 0.960 or less, and particularly preferably 0.959 or less.
• the Hermann orientation factor fc of the cellulose filaments is less than 0.965, preferably 0.951–0.958.
• the Hermann orientation factor can be determined, for example, by wide-angle X-ray scattering (WAXS) or small-angle X-ray scattering (SAXS).
• the cellulose filament has a thread thickness of 0.7 dtex to 10 dtex. It can be present in a cellulose filament bundle (multifilament) with a total density of 10 dtex to 3000 dtex.
• the cellulose filaments (preferably as bundles) can be unwound and wound onto another spool (secondary winding).
• secondary winding can be used to carry out further treatment steps on the cellulose filament bundle, such as annealing, impregnation, etc.
• the secondary winding is also carried out while wet, but after the solvent has been removed, i.e., without solvent or possibly only residual amounts of solvent.
• the filaments are dried on the first spool after production (primary spool) without being rewound onto the secondary spool, so that the secondary spool is created from the primary spool.
• drying takes place on the secondary spool.
• the dried cellulose filaments can then be rewound onto a new spool (tertiary winding).
• the device/method according to the invention were tested with a cellulose solution (viscous spinning mass) consisting, for example, of cellulose, NMMO, and water in a composition comprising 14.0% cellulose, 10.20% water, and 75.80% N-methylmorpholine N-oxide (all wt%).
• the cellulose solution was formed by extrusion and passed through a gas gap. Further cellulose solutions tested were spun in compositions ranging from 8% to 16% cellulose, a water content between 13.4% and 9.2%, and a tertiary amine oxide (NMMO) content between 78.6% and 74.9%.
• NMMO tertiary amine oxide
• the intrinsic viscosity (IV) of the celluloses used ranged between 350 ml/g and 770 ml/g, with a polymer dispersion index (PDI) of 2.0–10.0, preferably in the PDI range of 2–7, and an alpha content in the cellulose of 86–98%.
• PDI polymer dispersion index
• celluloses with average degrees of polymerization (DP) in the range of DP 400 to DP 1600 were used (DP determination by capillary viscometry according to DIN 54270).
• the concentration of cellulose material in the ionic liquids used can typically range from 1 to 20 wt%, depending on the degree of polymerization. Some studies have shown that higher concentrations of up to 20 wt% can be achieved, particularly when high-performance dispersants or special processing techniques are used.
• the choice of cellulose concentration in the ionic liquids depends on various factors, including the desired application, the type of cellulose, the solubility properties of the ionic liquid, and processing parameters such as temperature and treatment time of the cellulosic substrate. Higher cellulose concentrations have been shown to result in more viscous solutions, while lower concentrations (in the range of 12–17%) are better suited for the processing steps of the cellulose solution.
• the water content of cellulose solutions in ionic liquids can typically range from a few percent to 10 wt%. These products can also be manufactured in a relatively dry consistency, particularly if they are produced, stored, and processed under an inert gas atmosphere.
• a key advantage is that the water content of cellulose solutions in ionic liquids is precisely adjusted, controlled, and monitored, as excessive water content impairs the quality of the ionic cellulose solution and the materials produced from it. It has been shown that a low water content leads to better cellulose dissolution and, overall, more stable cellulose solutions, while a relatively high water content increases the viscosity of the cellulose solution and leads to undesirable effects such as poor dissolution of the cellulose substrate and consequently poor spinning conditions.
• the ionic liquids used have also enabled the processing of recycled pulp, cotton, and cellulose substrates from recycled textile and waste materials into filament strands.
• the raw materials used were purified and pretreated to remove impurities and improve their solubility in the ionic liquid. This can include steps such as crushing, grinding, extracting, washing and/or removing foreign matter.
• the device according to the invention also enabled the processing of pulps with a hemicellulose content between 3% and 20% and glucomannan and xylan contents between 1% and 10%.
• the pulps used had a carboxyl and carbonyl group content of 15–40 pmol/g each, heavy metal contents of less than 10 mg/kg, and alkali and alkaline earth contents in the range of 100–500 mg/kg pulp.
• a description of the pulp analysis can be found, for example, in the reference at http://www.gruberscript.net/23Zellstoffanalyse_chemisch.pdf.
• TAPPI Technical Association of the Pulp and Paper Industry
• TAPPI T 204 Determination of the alkali resistance of pulp (cold-insoluble substance content).
• TAPPI T 236 Determination of kappa number of pulp;
• TAPPI T 237 Determination of the carboxyl group number of pulp.
• radical scavenger chemicals such as propyl gallate, bases such as sodium hydroxide, and hydroxylamine are added to liquids in suitable quantities.
• a spinning machine unit can be comprised of a single spinning station or multiple spinning stations connected together.
• the spinning/shaping of the cellulose solution is carried out using the dry-jet-wet spinning process.
• the cellulose solution (spinning mass) forced through the individual spinning capillaries in the extrusion device is extruded into an air gap located below the spinneret and drawn to achieve the desired fiber properties and quality requirements.
• the extruded cellulose solution can be drawn in the air gap using a moving gas stream, preferably conditioned air. After drawing, the drawn cellulose solution enters the coagulation bath below to precipitate the cellulose into filament or thread form.
• the cellulose precipitation takes place in an aqueous coagulation bath, during which the solvent is partially extracted from the thread/filament and collected in the coagulation bath.
• a partial wash is performed in the form of solvent extraction.
• the aim here is to partially remove the solvent from the cellulose filaments.
• Water is the preferred washing medium.
• the washing medium and the filament bundle flow together through a fluid bed/wash bath.
• a structured surface of the fluid bed (wash channel) creates and maintains turbulence in the washing medium, which This leads to an intensification of the washing effect.
• the temperature of the washing medium can be increased to accelerate the fabric transport.
• the aqueous, solvent-containing, and highly swollen cellulose fiber bundle (cellulose multifilament) is continuously fed to a winding machine (primary winding) via guides after coagulation and washing.
• a winding machine primary winding
• the cellulose filaments are pulled forward and wound spirally in a crosswise pattern.
• Winding can be performed on any cylindrical or frustoconical bobbin (empty bobbin, tube, or other type of spool).
• Perforated bobbins of varying material compositions can also be used.
• the apparatus for carrying out the invention is by no means limited to the devices and methods illustrated, but other conventional fiber production devices can also be used to transport the fiber bundle, guiding the cellulose fiber to a winding system. This means that other suitable devices for linearly guiding a fiber between the coagulation bath, washing, fiber surface stabilization, and winding or further processing can also be used.
• the fiber guidance from the extrusion nozzle to the primary winding is designed in such a way that the sensitive, primary spun fiber bundle is not damaged by shear forces.
• the angle of the cross-wound filament is also adjusted accordingly to maintain a desired spool circumference, whereby, according to the invention, the cross-wound length of the product spool decreases in a specific ratio with increasing spool diameter, i.e., that an edge angle ⁇ of 90–70°, preferably 72–80°, results, or that the winding is adjusted so that the laying angle is 5–20°, preferably 10–14°. It has been shown that an initial laying angle of 13.5° over an initial length of 500–2000 m, followed by a uniform transition to a laying angle of 12° over a length of 500–7000 m, provides good treatment for the filament bundle.
• Test number speed Starting angle Initial length Laying angle Winder Note - m/min ° km ° Grades 1-3 7-1 230 27 7 11.5 1.5 7-2 240 27 3 12.5 2 7-3 235 28 5 12 1 7-4 230 29 7 12.5 1.5 7-5 235 28 5 12 1.5 7-6 240 29 7 11.5 1 7-7 240 27 7 12.5 1 7-8 230 27 7 12.5 2.5 7-9 230 29 3 11.5 2.5 7-10 230 29 7 11.5 2.5 7-11 240 29 3 12.5 3 7-12 240 29 3 11.5 1.5 7-13 235 28 5 12 2.5 7-14 240 27 3 11.5 1.5 7-15 230 29 3 12.5 1.5 7-16 230 27 3 11.5 1.5 7-17 230 27 3 12.5 1 7-18 235 28 5 12 3 7-19 240 27 7 11.5 2 Note: 1 - very good, 5 - bad
• a yarn winding machine is used, wherein the cellulose filament supply is provided by a continuous spinning machine.
• the swollen cellulose filaments are fed to the winding station at a fixed speed to ensure even winding.
• the thread winder is equipped with this feature.
• the winding speed is controlled by devices. Additionally, the ratio of extrusion speed to winding speed is kept constant. This ratio, also called the draw ratio, determines the desired production specification of the continuous filament yarn, expressed in, for example, dtex or denier. Selecting a suitable draw ratio also prevents overstretching or slackness of the yarn during the winding process.
• the filament yarn length change caused by the skein change results in negligible titer fluctuations, making the cellulose filament bundle ideally suited for textile and technical applications.
• the yarn is laid onto a cylindrical or conical spool body by means of a skein change guide, through which the yarn is continuously fed back and forth.
• the linear movement of the yarn and the rotation of the bobbin holder ensure that the continuously produced cellulose filament yarn is laid evenly on the typically perforated winding bobbin in a cylindrical, conical, or other desired geometric shape, while moist and containing cellulose solvent.
• bobbin holding systems are chosen that consist of at least one fixed bobbin unit. It is advantageous to use rotating bobbin holding carrier systems that consist of several individual bobbin carrier systems for holding the wound bobbin or empty bobbin, and that the primary winding of the moist cellulose filaments is connected to the continuously carried out spinning or thread manufacturing process.
• the bobbin holding system or driven rotary thread winder comprises a turntable, a linearly operating thread displacement mechanism (changing device), and a drive rotation mechanism required for the automatically initiated rotation of the empty and product bobbin spindles arranged on the turntable.
• the turntable is rotatably connected to the fixed mounting plate, with at least one, preferably several, and even more preferably two bobbin spindles installed on the turntable. are.
• the linear thread displacement and guidance mechanism (changing device) can be arranged in a housing that pivots towards the bobbin case.
• the force and rotation mechanism is located on the back of the mounting plate and is in transmission connection with the bobbin spindles.
• the bobbins (tubes, bobbins) are mechanically fixed (clamped) onto the rotating bobbin spindles.
• a thread winder has a revolving bobbin winding and holding system
• the desired bobbin weight or other bobbin parameters such as length, diameter, etc.
• the finished bobbin can be rotated around a centrally arranged axis of rotation, in a turret-like fashion, and turned into a finishing position in which the reserve bobbin body was located.
• the empty reserve spool body is then rotated into the product production position by a turret-like turn. This ensures that the continuous cellulose filament spinning process is not interrupted.
• a rotating spool holding system can also be replaced by a non-rotating yarn winding system, in which case, after the finished spool, the moist, solvent-containing product spool is exchanged for an empty spool. This results in a brief interruption of the regular spinning process.
• the deflection can be caused by the movement of the changing device or by the movement of the rotating spool itself, resulting from the increase in diameter during the winding process.
• the thread winder which is able to automatically change the spool, when a spool with moist, highly swollen cellulose fiber yarn has been produced, it is rotated from the production position to the holding position, and the stand-by spool is rotated from the holding position to the production position in a turret-like fashion.
• the yarn Since the yarn is automatically cut after the standby spool is rotated from the holding position to the producing position and vice versa, it can be wound onto the newly rotated spool.
• the spool is primarily wound and filled with moist cellulose yarn.
• the coil is removed manually or automatically downwards, upwards or to the side.
• the winding of the produced yarn therefore begins anew, since, as mentioned above, by simultaneously replacing and rotating the full production spool, the reserve spool is moved from the reserve position into the production or starting position, allowing the fiber production process to continue continuously with the new winding.
• the cellulose fiber yarn spool is now in the finishing position, with the desired and set production weight, and can be fed into the further processing of the process.
• the primary winding process can continue once the desired spool weight is reached, since the yarn winder has an automatic system for collecting the fiber cake.
• an automatic changer that rotates through full spools or a simple mechanism to secure only the spool can be used.
• Simple spool stand If a simple winding mechanism is used in a yarn winding machine, the primary winding must be interrupted by stopping the winding station once the desired production weight is reached. This also means that the continuous spinning process must be interrupted before an empty reserve bobbin can be placed on for the next winding operation.
• the continuously running yarn production process can be continued by using an automatically guided yarn winding process.
• the production efficiency of the process is increased while simultaneously reducing labor intensity and labor costs.
• Modern yarn winders are often automated and equipped with controls to monitor the winding process. This can include adjusting parameters such as speed, tension, lay-up angle, winding density, yarn run detectors, etc.
• the winding core of the inserted coil in the form of a bobbin, can be made of plastic, metal, or cardboard, either as a solid body or a perforated coil former.
• Metallic coil formers can be made of solid cylindrical or frustoconical aluminum, natural aluminum, powder-coated aluminum, stainless steel (ground on one side, bright on the other), or dimensionally stable plastics such as polypropylene (PP), as well as other plastics.
• the perforation of the coil body can be round hole, square hole, round oblong hole, rectangular oblong hole, as well as in all possible special hole shapes such as hexagon, square hole, diamond hole, triangular hole, keyhole, star hole and/or in combination as well as in any shape.
• the perforated spool area of the empty spool should be approximately 10–40% of the total spool surface area. Preferably in the range of 15–30%, more preferably in the range of 20–30%. This enables a rinsing or washing liquid flow rate of 1,000–10,000 liters/min per spool and a spool liquid flow rate of 10–50 liters/min per spool, or, based on the surface area, 50–500 liters/min per m2 of spool surface or 2–50 liters/min per kg of dry cellulose filament cake (cake washing liquid).
• Plastic spools for dyeing textile yarns also known as plastic dyeing cones, plastic dyeing tubes, etc., can also be used in the primary and secondary winding process according to the invention.
• Plastic textile yarn dyeing spools include their relatively light manufacturing process, chemical stability, insulating properties, and excellent strength. This is achieved because the plastic dyeing spools, for example those made of polypropylene, can be reinforced with glass fibers during the injection molding process. This ensures higher temperature resistance and dimensional stability. Their long-term thermal resistance is approximately 120 °C, making them suitable for hot water or hot water under increased pressure.
• coil formers are used in diameter dimensions of 30 to 80 mm, in coil former lengths of 150 - 300 mm, in the materials polypropylene (PP), high temperature resistant polypropylene (HT-PP), or in the material mixture of polycarbonate (PC) and acrylonitrile butadiene styrene (PC/ABS).
• PP polypropylene
• HT-PP high temperature resistant polypropylene
• PC/ABS acrylonitrile butadiene styrene
• coil formers that can be used in the primary winding method according to the invention are called “dye springs” or “one-way dye springs” and are also perforated. Can be used as a stackable, disposable spool or a reusable spool. The various perforations give the spools a degree of radial elasticity. These "springs" serve to keep the moist cellulosic continuous filament securely in shape during washing and post-treatment processes.
• the spools used should be compressible to minimize mechanical stress on the filament yarn during the washing process. This mechanical stress occurs when the solvent is replaced by detergent during washing, which can cause shrinkage or expansion of the spool cake.
• the wound spools can also be subsequently covered with nonwoven fabric for further washing. This facilitates efficient processing during secondary winding.
• Parallel washing machines are available for washing the wound cellulose fibers.
• the cross-wound reels are washed solvent-free in stages.
• the reels are placed on special supports into the parallel, batch-operated washing machines and pass through various washing stages, with each stage (washing cycle) lasting approximately 15-120 minutes on average.
• the washing liquor is kept moist with a batch volume of 2-8 liters per kilogram of cellulose substrate.
• the liquor is heated to a temperature of approximately 90 °C and pressurized to 1.1-3 bar.
• the parallel washing machines are operated an average of 2-50 times per day to achieve an annual production capacity of, for example, 5,000 tons.
• the solvent-free washed cross-wound reels emerging from the washing units can then be subjected to a pre-drying step and/or mechanical dewatering.
• the solvent-free washed cross-wound reels can undergo further treatments before the pre-drying step, as described above.
• the system components can be used, on the one hand, to remove the solvent from the cellulose substrates; on the other hand, if appropriate, further fiber substrate treatments, such as dyeing, can also be carried out in the multi-purpose units. This is possible, whereby the work processes are carried out separately.
• the heat requirement can be met by direct or indirect heating with steam, water, gas, electricity, or oil heating.
• washing liquid derived from the washing process containing the aforementioned cellulose solvents, such as amine oxides or ionic liquids, is recycled to the spinning process and the spinning bath as a diluent and precipitating agent.
• the process according to the invention is not limited to recycling the enriched wash water into the spinning process; rather, specially installed washing liquors, purification, and recovery processes can run in parallel with the yarn production process or independently.
• washing liquors, filtrations, ion exchange systems, membrane processes, and evaporation processes can be used to separate solids and water or for liquid/liquid separation.
• Corresponding apparatus and processes can be used individually or in combination.
• the washing process is carried out by pressure washing, whereby the washing liquid can move both from the inside out and from the outside in.
• the packing density of the product spool in the washing system determines the effectiveness of the washing and the resulting number of washing stages. Between washing stages, the detergent is exchanged in the opposite direction.
• the packing densities in the trials ranged from 50% to 83%.
• the liquor ratio ranged from 1:3 to 1:40, with the best washing results achieved in trials 9-3 and 9-8. Sufficient washing time, combined with an adequate liquor ratio and moderate pressure, likely contributed to the good washing results. to be responsible.
• a centrifuge rotating the spool generates a centrifugal force strong enough to separate the water from the swollen cellulose filament yarns, causing it to exit the spool radially.
• a rotational speed of 6500 rpm has been shown to produce a suitable and sufficiently dry filament cake, reducing the moisture content from an initial 230% to as low as 130%. This offers a significant advantage for subsequent processing steps, as it reduces the required drying energy. However, the same treatment can also be achieved by performing an intermediate drying step.
• the coils from the cake washing process must be removed from the pressure washing unit and fed into a dryer.
• the pressure washing tank can also be connected to a steam and compressed air supply to largely remove surface water before drying.
• the product coils of the cake washing process can be removed from the perforated pressure washing tubes and subjected to mechanically guided dewatering, such as centrifugation, and thus pre-dried.
• the cellulose filament spools are either removed directly from the cake washing or from the centrifuge, subjected to the treatments mentioned above, and fed into the drying step.
• the subsequent drying process can be carried out in a high-frequency oven, microwave dryer, tray dryer, or similar appliance, where the desired moisture content can be adjusted or the drying process can be completed.
• a high-frequency oven microwave dryer, tray dryer, or similar appliance
• additional dry air or hot air can be blown in and extracted to even out the heating and to remove any steam and moisture that may be produced.
• Drying devices equipped as high-frequency dryers have proven to be more effective than mechanical drying devices (EP 0075797 B1 Furthermore, the necessary singulation or combination of the coils for further processing such as packaging can be easily integrated into a subsequent automation process after the drying process.
• the moist primary product reels, emerging from the cake washing process step where solvent removal in a pressure vessel and/or further chemical treatment takes place, are fed into a drying system.
• the pressure vessel itself, or several adjacent pressure vessels, can serve as the drying system.
• the cellulose fiber spools fed into the drying system can be placed on perforated tubes of a pressure tube dryer.
• the drying agent such as hot air, is then passed through these tubes.
• the hot air exiting the perforated mounting tubes subsequently flows through the perforated washing spools for pre-drying or final drying of the produced cellulose fibers.
• the cellulose filaments can be rewound after or during the processing steps, i.e., transferred to other spool bodies (secondary and tertiary winding). It is advantageous for the process flow to partially dry the cellulose filaments before secondary winding.
• intermediate drying is carried out by removing a portion of the water bound in the spool using a thermal, mechanical, or other method. The drying process is designed so that the escaping water is removed very gently and homogeneously across the entire cross-section. On the one hand, as much water as possible must be removed. Water must be removed, while enough water remains on the coil to allow for easy unwinding during the secondary winding process. A humidity level in the range of 50–200% relative humidity (particularly preferably 120–150%) is preferred. This partial drying process is preferably carried out in such a way as to achieve a homogeneous humidity level across the entire coil.
• a suitable release agent such as fatty acid esters, mineral oils, silicone oils, and other suitable substances, is applied to the filament using a suitable technical device, such as an oil roller, during secondary winding.
• a suitable technical device such as an oil roller
• the coil is unwound and subjected to the treatment described above, and then rewound onto a coil blank.
• the winding should be done in such a way that the coil retains its shape, but also very loosely, so that it is suitable for the subsequent process steps.
• a cake density of approximately 0.3–0.5 kg/L has proven very useful in this regard.
• drying is achieved by supplying energy in a thermal, electromagnetic, convective, or other suitable form.
• the drying process is carried out as homogeneously as possible until a desired residual moisture content is reached, allowing for trouble-free rewinding.
• the packing density decreases during drying. This effect contributes to gentle drying and thus promotes the production of high-quality fibers.
• the packing density decreases.
• the coil is preferably rewound a second time (tertiary winding) to achieve a final shape preferred by the customer.
• the winding parameters are chosen to produce a stable final coil.
• the humidity for this process step is between 60-90% relative humidity, preferably between 75-85% relative humidity.
• a final conditioning process can then be carried out, e.g., storage at the desired humidity or drying to achieve the appropriate final fiber moisture content. Drying is again achieved by supplying energy in a thermal, electromagnetic, convective, or other suitable form.
• the degree of crystallinity x ⁇ sub>c ⁇ /sub> and a disorder parameter k which is a measure of the lattice defects in the crystallites, were determined from the normalized scattering curves.
• the fibers were horizontally bonded to the sample carrier using an electrically conductive substrate.
• a fiber bundle was immersed in liquid nitrogen and broken after freezing. The fiber bundle was then vertically attached to a conductive substrate on the sample carrier. Finally, the fiber samples were sputtered with a platinum layer (4 nm thick) to prevent electrostatic charging.
• the investigations were performed using a GeminiSEM 300 scanning electron microscope (SEM) (Zeiss, Germany), operated at an accelerating voltage of 5 kV and the lowest possible beam current to minimize radiation damage and fiber charging. SEM results of the fiber surface and cryogenic fracture are presented in the following sections. Figures 3 and 4 shown.
• WAXS Wide-angle X-ray scattering
• a layer of parallel cellulose fibers was fixed with cyanoglue to a fiber sample holder with a hole diameter of 2.3 cm (oriented fiber preparation).
• Hermans' orientation factor fc as well as other orientation parameters (OG (hkl) and OGI (hkl) )
• the distribution of the (004) lattice plane reflection (chain direction reflection) of the cellulose structure was measured.
• orientation parameters fc and OG(hkl) were determined.
• a linear background was subtracted from the scattering curves. Since the subsurface is formed by the isotropically distributed lattice planes, neglecting the small amount of air scattering, an integral orientation parameter OGI(hkl) can be used as a measure of the proportion of oriented lattice planes to the total number of scattering lattice planes.
• the fiber orientation of two samples was determined.
• the first sample is a conventionally produced reference sample with continuous processing, immediate in-line washing and drying, and winding; and the second sample is produced according to the invention with moist, solvent-based winding followed by subsequent washing and drying.
• the results of the calculation of the various orientation parameters are given in the following table.
• the inventive fiber sample exhibits significantly less orientation compared to the reference sample.
• the half-width of the distribution curve is considerably higher, resulting in lower values for the orientation parameters OG(004) and fc.
• the proportion of oriented regions (OGI) is also lower than in the reference sample.

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  • 2024-05-17 EP EP24176640.1A patent/EP4650499A1/fr active Pending
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