EP3090081B1 - Cellulose fibre - Google Patents

Description

The present invention relates to a cellulosic fiber of the genus Lyocell.

In recent decades, due to the environmental problems of the known viscose process for producing cellulosic fibers, intensive efforts have been made to provide alternative, more environmentally friendly processes. As a particularly interesting possibility has emerged in recent years to dissolve cellulose without forming a derivative in an organic solvent and to extrude molded articles from this solution. Fibers spun from such solutions have been assigned the genus name Lyocell by BISFA (The International Bureau for the Standardization of Man Made Fibers), where organic solvent means a mixture of an organic chemical and water.

Furthermore, such fibers are also known by the term "solvent-spun fibers".

It has been found that, as an organic solvent, in particular a mixture of a tertiary amine oxide and water is outstandingly suitable for the production of lyocell fibers or other shaped articles. The amine oxide used is predominantly N-methylmorpholine-N-oxide (NMMO). Other suitable amine oxides are in the EP-A 553,070 revealed.

In the EP 0 356 419 A a technical embodiment of the method for producing a solution of a pulp in an amine oxide is described. In this case, a suspension of the crushed pulp is transported in an aqueous tertiary amine oxide in the form of a thin layer over a heating surface, water evaporated and thereby produced a spinnable cellulose solution.

A process for spinning cellulose solutions in amine oxides is known from US 5,156,062 US 4,246,221 known. According to this method, filaments extruded from a spinneret are passed through an air gap, stretched there, and the cellulose is subsequently precipitated in an aqueous spinning bath. The process is known as "dry / wet spinning" or "air gap spinning".

The entire process for producing fibers from solutions of cellulose in a tertiary amine oxide is hereinafter referred to as "amine oxide process", wherein by the abbreviation "NMMO" in the following all tertiary amine oxides are meant, which can dissolve cellulose. Fibers produced by the amine oxide process are characterized by high fiber strength in the conditioned and in the wet state, a high wet modulus and a high loop strength.

The conditions in the air gap such as temperature, humidity, cooling rate of the filaments and distortion dynamics are of great importance for the properties of the resulting fibers (see Volker Simon, Transactions of the American Society of Mechanical Engineers (ASME) 118 (1996) No. Febr., Pp. 246-249 ").

Technical embodiments of the spinning process have been described in numerous documents:

The WO 93/19230 describes a process in which the extruded filaments are cooled by blowing with air just below the nozzle. The WO 94/28218 describes a nozzle design and a blowing method. The WO 95/01470 claims a laminar flow in the WO 93/19230 described cooling gas flow. The WO 95/04173 describes a further technical embodiment of the blowing. In the WO 96/17118 the moisture content of the blown air is defined. In the WO 01/68958 the blow-by airflow is directed downwards at an angle of 0 ° to 45 ° to the extruded filaments. The WO 03/014436 describes a blowing device with extraction of the blowing air. In the WO 03/057951 claims the shielding of a part of the air gap with respect to the blowing air. In the WO 03/057952 a turbulent gas stream is described for cooling the filaments. The WO 05/116309 also describes the shielding of a part of the air gap with respect to the blowing air.

The fibers / filaments obtained by the air-gap spinning process differ structurally from the known viscose fibers. While the crystalline orientation is approximately the same for both viscose fibers and lyocell fibers (largely parallel arrangement of the cellulose chains located in the ordered regions of the fiber to the fiber axis), there are marked differences in the amorphous orientation (higher parallelism of the disordered portions in lyocell fibers).

The properties of the lyocell fiber such as high crystallinity, long and thin crystallites and the high amorphous orientation prevent sufficient binding of the crystallites across the fiber axis. In the wet state, the swelling of the fibers additionally reduces the binding forces transverse to the fiber axis and thus leads to the splitting off of fiber fragments under mechanical stress. This behavior is called wet fibrillation and results in reduced quality in the textile end product in the form of graying and hairiness.

Overviews of the state of research in this area are provided by the Works by Josef Schurz, Jürgen Lenz: "Investigations on the structure of regenerated cellulose fibers" in Macromolecular Symposia, Volume 83, Issue 1, pages 273-289, May 1994 and Fink HP, Weigel P, Purz HJ, Ganster J "Structure formation of regenerated cellulose materials from NMMO-solutions" Prog.Polym.Sci. 2001 (26) p 1473-1524 ,

• Variation der Herstellungsbedingungen oder
• Einführung eines Schrittes der chemischen Vernetzung während des Produktionsprozesses

Previous efforts to improve the wet fibrillation resistance of lyocell fibers went in two directions:

• Variation of production conditions or
• Introduction of a chemical crosslinking step during the production process

An assessment of the success of each described measures to reduce fibrillation, however, is hardly possible. There is no standardized method for measuring fibrillation behavior, and the methods used in the patent literature are all proprietary.

• zusätzliche Chemikalien/Chemikalienkosten/Abwasserprobleme bei der Herstellung der Faser
• Umweltbelastung bei der Herstellung der Vernetzerchemikalien
• Unzureichende Hydrolysestabilität der Vernetzung unter den Bedingungen der textilen Verarbeitung.

The second approach, chemical crosslinking, has a number of disadvantages, such as

• additional chemicals / chemical costs / wastewater problems in the production of the fiber
• Environmental impact in the production of crosslinker chemicals
• Insufficient hydrolytic stability of the crosslinking under the conditions of textile processing.

Examples of the method of chemical crosslinking are in the EP 0 53 977 A . EP 0 665 904 A respectively. EP 0 943 027 A described.

For the former procedure, the variation of the manufacturing conditions, numerous documents have been published. However, the described methods have either only led to a slight improvement in the fibrillation behavior, which does not result in a lasting improvement in processability, or the processes could not be realized on an industrial scale as a result of costs / technical effort.

In the SU 1,224,362 For example, a spinning solution of a single pulp is spun into a bath containing NMMO in amyl alcohol and isopropanol, respectively. The WO 92/14871 claims a fiber with reduced fibrillation, characterized in that the pH of the spin bath and subsequent wash baths is below 8.5. No information is given on the type of pulp or spinning conditions.

The WO 94/19405 describes a process wherein a pulp mixture is used. However, no reference is made to the fibrillation tendency of the spun fibers.

The WO 95/02082 describes a combination of process parameters, represented in a mathematical expression, for producing a low fibrillation fiber. The mentioned process parameters are the spin hole diameter, the spin mass output, the filament titer, the air gap width and the air gap humidity. The pulp used is not described in detail, the spinning temperature is only 115 ° C.

In the WO 95/16063 The extruded filaments are brought into contact with a surfactant in dissolved form in the spin bath or in the aftertreatment baths. The type of pulp used is not specified, the spinning temperature is 115 ° C.

The WO 96/07779 uses as spinning spin an organic solvent, preferably polyethylene glycol. No details are given about the pulp used or about the textile mechanical properties of the resulting fibers. The spinning temperature is 110 ° C indicated.

In the WO 96/07777 The extruded filaments are brought into contact with an aliphatic alcohol in the air gap, which is in gaseous form. The type of pulp used is not specified, the spinning temperature is 115 ° C.

The WO 96/20301 describes a process wherein the shaped solution is passed in succession through at least two precipitation media, wherein in the first precipitation medium a slower Coagulation of the cellulose over the latter precipitation medium takes place. In the examples, a higher alcohol is preferably used as the first precipitation medium. The pulp used is not specified, the spinning temperature is 115 ° C.

The WO 96/21758 describes a process in which the shaped solution is blown in the air gap in an upper zone with higher humidity air and in a lower zone with lower humidity air. As pulps, individual pulps of different degrees of polymerization are used, the spinning temperature is 115 ° C.

The EP 0 853 146 describes a two-stage process wherein the residence time of the fibers in the first precipitation step is adjusted so that only the tackiness of the surface of the fiber-formed solution is inhibited and the fibers are coagulated in a later precipitation stage. The spinning temperature in the examples is 109-112 ° C.

In the WO 97/23669 is spun into a spin bath with an NMMO content above 60%. It is used a single pulp.

In the WO 97/35054 describes a combination of parameters for obtaining a low fibrillation fiber, namely the concentration of the spinning solution, the delay in the air gap and the nozzle hole diameter. It is a single pulp used, the spinning temperature is in the range of 80 - 120 ° C.

In the WO 97/38153 Also described is a combination of parameters for obtaining a low-fibrillation fiber, namely air gap length, spinning speed, air gap residence time, air gap blowing air velocity, blowing air moisture content, and product of air gap residence time and blowing air moisture content , The pulp used is a single pulp.

In the WO 97/36028 After leaving the precipitation bath, the fibers are treated with a solution of 40-80% NMMO, if appropriate with the addition of an additive.

In the WO 97/36029 After leaving the precipitation bath, the fibers are treated with a zinc chloride solution.

In the WO 97/46745 After leaving the precipitation bath, the fibers are treated with a NaOH solution.

In the WO 98/02602 After leaving the precipitation bath, the fibers are treated in a relaxed state with a NaOH solution.

In the WO 98/06745 a pulp mixture is used obtained by mixing solutions of pulps of different degrees of polymerization, with respect to the spinning temperature is not specified.

In the WO 98/09009 describes the addition of additives (polyalkylenes, polyethylene glycols, polyacrylates) to the spinning mass. The pulp used is a single pulp.

In the WO 98/22642 If a pulp mixture low degree of polymerization is used, the spinning temperature is 110 - 120 ° C.

In the WO 98/30740 a pulp mixture is also used, the spinning mass is spun by a centrifugal spinning process, the spinning temperature is 80-120 ° C.

In the WO 98/58103 Details are given of the molecular weight distribution of the pulp in a pulp from a pulp mixture, resulting in stable spinning. However, no reference is made to the fibrillation behavior of the resulting fibers / filaments.

In the DE 19753190 After leaving the precipitation bath, the fibers are treated with a concentrated NMMO solution.

In the GB 2337990 If a cosolvent is used to dissolve the individual pulp, the resulting solution is spun at 60-70 ° C.

In the US 6471727 For example, a dope composed of a single pulp of high hemicellulose and lignin content is processed by a dry / wet or meltblown spinning process.

In the WO 01/81663 a spinneret is described in which the spinning capillary is heated directly near the outlet cross-section. This measure is intended to reduce the fibrillation tendency of lyocell fibers, but no experimental conditions are given.

The WO 01/90451 describes a spinning process characterized by a mathematical relationship containing the heat flux density in the air gap and the length to diameter ratio of the extrusion channel. Fibers spun according to the invention should have a lower fibrillation tendency, but no further details are given.

In the US 6773648 a meltblown process for producing a fibrillation reduced fiber is published. Meltblown fibers are not suitable for textile use due to their uneven titer.

In the DE 10203093 For example, a fiber of low fibrillation is prepared by spinning two spinning solutions of different cellulose concentration from a single pulp from a bicomponent nozzle. No example is given.

In the DE 10304655 For improving the solution quality, polyvinyl alcohol is added to the NMMO. The conditions for spinning the claimed less fibrillating fiber will not be specified.

On the one hand, the special structure of the lyocell fiber leads to excellent textile-mechanical properties such as high strength both in the dry and wet state and a very good dimensional stability of the fabric produced therefrom, on the other hand too low flexibility (high brittleness) of the fibers, resulting in a drop in the Abrasion resistance viscose fibers in the fabric reflected.

The term flexibility (compliance) is defined by Hooke's law as the quotient of the strain of the test body and the strain causing the strain. Increasing the flexibility of lyocell fibers is the goal of a number of publications:

A flexible lyocell fiber is described in US patent no EP 0 686 712 , The patent claims a fiber with reduced NMR order, obtained by adding nitrogen-containing substances such as urea, caprolactam or aminopropanol to the polymer solution or in the precipitation bath. However, a fiber with very low wet strength is obtained; Thus, the fiber clearly differs from the fibers of the invention described below.

In the WO 97/25462 there is described a process for producing a flexible and fibrillation-reduced fiber, wherein the shaped fiber after the precipitation bath is passed through a washing and aftertreatment bath containing an aliphatic alcohol, optionally additionally with a sodium hydroxide additive. The properties of the resulting fibers are described only inadequate, in particular lacking dry strength and wet strength data, which would allow classification into the "Höller diagram" described in more detail below.

It can be said, however, that when comparing the fiber extensions given in this document with the corresponding data of the fibers according to the invention in the examples of the present application, the fiber differs markedly and that due to the low elongation values mentioned in this document, the flexibility of the fiber according to the above definition of flexibility can not be very high. The improvement in fibrillation behavior mentioned in the text of the document is not supported by any data.

The documents EP 1 433 881 . EP 1 493 753 . EP 1 493 850 . EP 1 841 905 . EP 2 097 563 and EP 2 292 815 describe fibers or filaments, preferably for the application of tire cord, prepared by adding polyvinyl alcohol to the NMMO / spinning solution. The fibers / filaments are characterized by high strength but low elongation, accordingly, their flexibility according to the above definition can only be small.

Other publications that indicate that the addition of additives to the dope may exert an influence on the fibrillation behavior and / or the flexibility of the fiber are
Chanzy H, Paillet m, Hagege R "Spinning of cellulose from N-methylmorpholine N-oxides in the presence of additives" Polymer 1990, 31, p 400-5
Weigel P, Gensrich J, Fink HP "Structure formation of cellulose fibers from amine oxide solutions" Lenzinger reports 1994; 74 (9), p 31-6 and
Mortimer SA, Peguy AA "Methods for reducing the tendency of lyocell fibers to fibrillate" J.appl. Polym. Sci. 1996, 60, p 305-16 ,

The WO 2014/029748 (not prepublished) describes the preparation of solvent-spun cellulose fibers especially from solutions in ionic liquids. Further prior art is from the documents DE 10 2011 119 840 A1 . AT 506 268 A1 . US 6,153,136 . CN 102477591A . WO 2006/000197 . EP 1 657 258 A1 . US 2010/0256352 A1 . WO 2011/048608 A2 . JP 2004/159231 A and CN 101285213 A known.

The invention of viscose fibers (Cross and Bevan 1892, GB 8700) dates back over a hundred years. Despite production weaknesses (environmental problems) and properties (in the standard type poor washing behavior) over one million tons of this fiber genus are produced each year.

The further development of the old method after the Second World War (polynosic and modal fibers) led to fibers with better washing behavior and higher dimensional stability, but could not change the intrinsic properties of the process (environmental relevance and due to the many process steps extremely complex process).

Conversely, in the development of the new fiber type "Lyocell" it was found that due to their different structure, the fiber places special demands on the processing conditions and thus the proven methods of processing viscose or modal fiber in the textile chain can not be used. Especially in dyeing and wet finishing, special fiber-adapted machines and processing settings are required. This is still considered a disadvantage today, over 20 years after the market launch of the lyocell fiber.

• geringere Fibrillationsneigung im nassen Zustand
• eine höhere Flexibilität (geringere Sprödigkeit)

zu verleihen.It would be desirable, while retaining the excellent properties of the lyocell fiber (such as high wet strength, high wet modulus, thus significantly improved washability and dimensional stability to viscose fibers) of the fiber, certain properties of the viscose fiber such as

• lower fibrillation tendency in the wet state
• a higher flexibility (less brittleness)

to rent.

It is therefore an object of the present invention to provide a "viscose-like" lyocell fiber with which processing of the fiber is made possible by the known and proven methods of viscose processing.

The change in properties should be achieved solely by choosing suitable process parameters in the production of the fiber, without resorting to chemicals foreign to the process as additives to the spinning mass, to the spinning bath or during the aftertreatment have to. Any additional chemical in the system, be it as an additive to the spinning mass or spin bath conditioned increased effort in the recovery and represents a cost factor.

• Höller-Faktor F2 ≥ 1, bevorzugt ≥ 2
• Höller-Faktor F1 ≥ -0,6
• Höller-Faktor F2 ≤ 6 sowie
• Höller-Faktor F2 minus 4,5*Höller-Faktor F1 ≥ 1, bevorzugt ≥ 3.

The object of the present invention is achieved by a cellulosic fiber of the genus Lyocell, which has a titer of 0.8 dtex to 3.3 dtex and is characterized by the following relationships:

• Höller factor F2 ≥ 1, preferably ≥ 2
• Höller factor F1 ≥ -0.6
• Höller factor F2 ≤ 6 as well
• Höller factor F2 minus 4.5 * Höller factor F1 ≥ 1, preferably ≥ 3.

Brief description of the figures

• FIG. 1 shows a Höller diagram of commercially available fibers from regenerated cellulose before the development of the lyocell fiber.
• FIG. 2 in the Höller diagram shows the area in which the fibers according to the invention are located.
• FIG. 3 shows a Höller diagram in which the fiber according to the invention is compared to a conventional lyocell fiber.

Detailed description of the invention

In the following, the novel and inventive lyocell fibers are described on the basis of the so-called "Höller factors" F1 and F2 as well as demarcated from known cellulosic man-made fibers of the prior art.

While the basic chemical structure of man-made cellulosic fibers such as viscose fibers but also Lyocell fibers is essentially the same (cellulose), the fibers differ based on factors such as crystallinity or orientation especially of the amorphous regions. These factors are difficult to demarcate quantitatively.

It will also be apparent to those skilled in the art that a lyocell fiber, e.g. from a viscose fiber by textile mechanical parameters (such as strength values), but also by less clearly definable properties, e.g. the textile "handle" is different. Likewise, there are marked differences between the various types of cellulose fiber produced by the viscose process, e.g. (Standard) viscose fiber, modal fiber or polynose fiber.

in the Review R. Höller "New Method for Characterizing Regenerated Cellulose Fibers" Melliand Textilberichte 1984 (65) p 573-4 could a clear demarcation of the different types of fibers known at that time from Regeneratcellulose, ie by the viscose process produced fibers, from each other by quantitative characteristics are shown.

The complexity of comparing a larger number of fiber properties could be greatly simplified by factor analysis according to this proposal via the formation of a few, subdividing fibers into groups of similar properties. Factor analysis is a multivariate statistical method that allows a set of correlated features to be reduced to a smaller number of uncorrelated factors.

The textile mechanical properties used by Höller for the factor analysis were the maximum tensile strength conditioned (FFk) and wet (FFn), the maximum tensile elongation conditioned (FDk) and wet (FDn), the wet modulus (NM), the loop strength conditioned (SFk) and the knot strength conditioned ( KFK).

All of these parameters as well as their determination are known to the person skilled in the art, see in particular the BISFA regulation " Testing methods viscose, modal, lyocell and acetate staple fibers and tows "Edition 2004 Chapters 6 and 7 , and are described in more detail below.

$$\begin{array}{l}\mathrm{Höller\; Faktor\; F}2=-\mathrm{7,070}+\mathrm{0,02771}\mathrm{xFFk}-\mathrm{0,04335}\mathrm{xFDk}+\mathrm{0,02541}\mathrm{FFn+}\mathrm{0,03885}\mathrm{FDn}-\\ \mathrm{0,01542}\mathrm{xNM}+\mathrm{0,2891}\mathrm{xSFk}+\mathrm{0,1640}\mathrm{xKFk}\mathrm{.}\end{array}$$

In the fiber collective present in Höller, 87% to 92% of the variance between the samples could be detected by only two factors (see FIG. 1 ). These two factors are calculated as follows: $$\begin{array}{l}\mathrm{<figure-callout\; id="1"\; label="Höller\; Factor\; F"\; filenames="imgf0002.png"\; state="\{\{state\}\}">Höller\; Factor\; F</figure-callout>}1=-\mathrm{1,109}+0.03992\mathrm{xFFk}-0.06502\mathrm{xFDk}+0.04634\mathrm{xFFn}-0.04048\mathrm{xFDn}+\\ 0.08936\mathrm{X\; nm}+0.02748\mathrm{xSFk}+0.02559\mathrm{xKFk}\end{array}$$

$$\begin{array}{l}\mathrm{Höller\; Factor\; F}2=-\mathrm{7,070}+0.02771\mathrm{xFFk}-0.04335\mathrm{xFDk}+0.02541\mathrm{FFn\; +}0.03885\mathrm{FDn}-\\ 0.01542\mathrm{X\; nm}+.2891\mathrm{xSFk}+.1640\mathrm{xKFk}\mathrm{,}\end{array}$$

How out FIG. 1 As can be seen, this analysis - based on clearly measurable parameters - allowed a clear demarcation of the different fiber types.

FIG. 1 shows in the coordinate system of the Höller factors F1 and F2 the Höller-tested fiber collective of 70 samples using commercially available fibers from regenerated cellulose. Along the factor F1, the division into (standard) viscose fibers and modal fibers can be seen, which are also cited by the BISFA as different Fasergattungen (although they are prepared by the same basic process, just the viscose process). To the left of the ordinate is the area of the (standard) viscose fibers (in FIG. 1 labeled "V"). Substantially to the right of the ordinate is the modal fiber region, which is subdivided into two subgroups, namely HWM ("high wet modulus") fibers and polynosic ("PN") fibers. The graph also shows a border (dashed line), beyond which none of the fibers of regenerated cellulose investigated at that time was located. However, lyocell fibers were still at the experimental stage and not commercially available at the time of this publication.

Currently commercially available lyocell fibers have Höller Fl values of 2 to 3 and F2 values of 2 to 8. In the "Höller diagram" according to FIG. 1 Therefore, such fibers would be located beyond the above-mentioned limit, from which the clear difference between the fibers of the viscose group and the lyocell fibers can already be seen in purely optical terms.

• Untere Grenze F2 = 1
• Linke Grenze F1 = -0,6
• Obere Grenze F2 = 6
• Rechte Grenze definiert über die Beziehung:
  • Höller-Faktor F2 minus 4,5*Höller-Faktor F1 ≥ 1, bevorzugt ≥ 3

The fiber according to the invention now lies in a region of the Höller diagram, which can be represented by a quadrilateral.
The sides of the square correspond to the following values or relationships:

• Lower limit F2 = 1
• Left limit F1 = -0.6
• Upper limit F2 = 6
• Right boundary defined by the relationship:
  • Höller factor F2 minus 4.5 * Höller factor F1 ≥ 1, preferably ≥ 3

The resulting from this relation arrangement of the invention Lyocell fiber in Höller diagram is in FIG. 2 shown. The fiber according to the invention thus occupies the Höller diagram roughly speaking the space above the abscissa and around the ordinate as well as to the left of it and is clearly delimited from currently commercially available lyocell fibers, roughly speaking (clearly) to the right of the ordinate in the Höller diagram.

Conversely, the Lyocell fiber according to the invention in the Höller diagram is close to the field of (standard) viscose. In fact, it has been found that the lyocell fiber according to the invention by far has "viscose-like" properties in terms of its processability than the currently commercially customary lyocell fibers.

• Die erfindungsgemäße Faser kann als Flächengebilde wie Viskose im Strang gefärbt werden (herkömmliche Lyocell-Fasern können nur breit gefärbt werden)
• Nicht mit einer Harzausrüstung hochveredelte Flächengebilde (wie Gestricke) aus der erfindungsgemäßen Faser behalten beim Waschen länger ein unverändertes Warenbild
• Flächengebilde aus der erfindungsgemäßen Faser weisen eine Scheuerfestigkeit wie Flächengebilde aus Viskose auf und weisen damit eine Verbesserung gegenüber herkömmlichen Lyocell-Fasern um das Doppelte auf.

The "viscose-like" properties in textile practice have the following property changes:

• The fiber of the invention can be dyed as a sheet such as viscose in the strand (conventional Lyocell fibers can only be dyed wide)
• Non-resin-finished fabrics (such as knitted fabrics) made of the fiber according to the invention retain an unaltered fabric appearance during washing
• Sheets made from the fiber according to the invention have scouring resistance, such as viscose fabrics, and thus exhibit a twofold improvement over conventional lyocell fibers.

However, the fiber of the present invention retains the high dimensional stability of washing processes characteristic of the lyocell fiber.

• Als der Fasergattung Lyocell zugehörig ist ein Rest-Lösungsmittelgehalt nachweisbar (insbesondere im Fall von nach dem Aminoxid-Verfahren hergestellten Fasern Reste an NMMO)
• Die Faser enthält ungleich einer nach dem Viskoseverfahren hergestellten Faser keinen Schwefel.

Although the areas in the Höller diagram of the fiber according to the invention and of (standard) viscose fibers as well as partly modal fibers overlap, the types of fiber can clearly be differentiated from one another on the basis of the fundamental differences in the production process, since the fiber according to the invention can be analyzed analytically from A distinction can be made between fibers produced by the viscose process, such as (standard) viscose fibers and modal fibers:

• A residual solvent content is detectable as belonging to the fiber genus Lyocell (especially in the case of fibers produced by the amine oxide process, residues of NMMO)
• The fiber does not contain sulfur, unlike a fiber made by the viscose process.

The wet scrubbing behavior of the fiber according to the invention is between 300 and 5000 revolutions by the method described below up to fiber breakage, preferably between 500 and 3000 revolutions.

The flexibility (i.e., the quotient FDk / FFk) of the fiber of the invention is preferably between 0.55 and 1.00, preferably between 0.65 and 1.00.

It has been shown that the Martindale dry rubbing of a single jersey 150 g / m ² from a ring yarn Nm 50/1 from the fiber according to the invention can be between 30,000 and 60,000 turns until the formation of holes.

The fiber according to the invention is preferably characterized in that it is produced by the amine oxide process.

The fiber of the invention is preferably as a staple fiber, i. as cut fibers, before.

The property change according to the invention of lyocell fibers in the direction of a viscose-like lyocell fiber and thus the repositioning of the fiber data in the Höller diagram is achieved according to the present invention by careful adjustment of the raw material and the process conditions:

1) pulp

To produce the fiber according to the invention, a defined molecular weight distribution of the raw material used is required. This is achieved in particular by mixing two or more individual pulps. Accordingly, the fiber according to the invention is preferably characterized in that it is made from a mixture of at least two different pulps.

1. a) Der Anteil an Cellulosen oder Cellulosebegleitstoffen (polymere Pentosane und Hexosane wie Xylan, Glucomannan, niedermolekulares beta-1,4-Glucan) mit einem Polymerisationsgrad von kleiner als 50 liegt unter 2% (bezogen auf die Zellstoffmischung), bevorzugt unter 1,5 % (Bestimmung Molekulargewichtsverteilung mit GPC/SEC mit MALLS Detektion in DMAC/LiC1, Bohrn, R., A. Potthast, et al. (2004). "A novel diazo reagent for fluorescence labeling of carboxyl groups in pulp." Lenzinger Berichte 83: 84-91 ).
2. b) Ein Anteil von 70% bis 95% der Zellstoffmischung hat eine Grenzviskositätszahl im Bereich von 250 bis 500 ml/g, bevorzugt 390 bis 420 ml/g (gemessen nach SCAN-CM 15:99), im folgenden "niedermolekulare Komponente" genannt.
3. c) Ein Anteil von 5% bis 30% der Zellstoffmischung hat eine Grenzviskositätszahl von 1000 bis 2500 ml/g, bevorzugt 1500 - 2100 ml/g, im folgenden "hochmolekulare Komponente" genannt.
4. d) Bevorzugt beträgt der Anteil der niedermolekularen Komponente 70 - 75%, wenn die hochmolekulare Komponente eine Grenzviskositätszahl von 1000 - 1800 ml/g aufweist bzw. 70 - 95%, wenn die hochmolekulare Komponente eine Grenzviskositätszahl > 2000 ml/g aufweist.
5. e) Weiters ist die Reinheit der eingesetzten Zellstoffe von Bedeutung: Die Reinheit ist definiert als der Mittelwert der Alkalibeständigkeiten R10 und R18 nach DIN 54355 (1977), Bestimmung der Beständigkeit von Zellstoff gegen Natronlauge (Alkalibeständigkeit). Dieser Wert entspricht etwa dem Alpha-Cellulose-Gehalt nach TAPPI T 203 CM-99. Die Reinheit der niedermolekularen Komponente beträgt > 91%, bevorzugt > 94%, die Reinheit der hochmolekularen Komponente > 91%, bevorzugt > 96%.

The molecular weight distribution is characterized by the following parameters:

1. a) The proportion of celluloses or cellulose accompanying substances (polymeric pentosans and hexosans such as xylan, glucomannan, low-molecular weight beta-1,4-glucan) having a degree of polymerization of less than 50 is less than 2% (based on the pulp mixture), preferably less than 1.5 % (Determination of molecular weight distribution with GPC / SEC with MALLS detection in DMAC / LiC1, Bohr, R., A. Potthast, et al. (2004). "A novel diazo reagent for fluorescence labeling of carboxyl groups in pulp." Lenzing reports 83: 84-91 ).
2. b) A proportion of 70% to 95% of the pulp mixture has an intrinsic viscosity in the range of 250 to 500 ml / g, preferably 390 to 420 ml / g (measured according to SCAN-CM 15:99), hereinafter referred to as "low molecular weight component" ,
3. c) A proportion of 5% to 30% of the pulp mixture has an intrinsic viscosity of 1000 to 2500 ml / g, preferably 1500 to 2100 ml / g, hereinafter referred to as "high molecular weight component".
4. d) Preferably, the proportion of the low molecular weight component is 70-75%, if the high molecular weight component has an intrinsic viscosity of 1000 - 1800 ml / g or 70 - 95%, if the high molecular weight component has an intrinsic viscosity> 2000 ml / g.
5. e) Furthermore, the purity of the pulps used is of importance: The purity is defined as the mean of the alkali resistance R10 and R18 according to DIN 54355 (1977), determination of the resistance of cellulose to caustic soda (alkali resistance). This value corresponds approximately to the alpha-cellulose content according to TAPPI T 203 CM-99. The purity of the low molecular weight component is> 91%, preferably> 94%, the purity of the high molecular weight component> 91%, preferably> 96%.

It has been found that, in particular when high-purity pulps such as cotton-linters pulps are used, it is easier to produce fibers having the properties according to the invention.

It has also been found that pulps made from recycled cotton fibers (RCF) are also suitable for the production of fibers according to the invention. Such pulps can be made according to the teaching of the publication "Process for pretreating reclaimed cotton fibers used in the production of molded bodies from regenerated cellulose" (Research Disclosure, www.researchdisclosure.com , database number 609040, published on December 11, 2014) become.

2) spinning conditions

1. i) Der Spinnmassedurchsatz soll zwischen 0,01 und 0,05 g/Düsenloch/min, bevorzugt zwischen 0,015 und 0,025 g/Düsenloch/min liegen.
2. ii) Luftspaltlänge: Die Vorgangsweise zur Herstellung der erfindungsgemäßen Faser unterscheidet sich vom Stand der Technik ( WO 95/02082 , WO 97/38153 ) darin, dass die Luftspaltlänge keinen relevanten Parameter darstellt. Bereits ab 20 mm Luftspalt werden erfindungsgemäße Fasern erhalten.
3. iii) Klima im Luftspalt: Auch darin unterscheidet sich die Herstellung der erfindungsgemäßen Faser vom Stand der Technik ( WO 95/02082 , WO 97/38153 ), dass Feuchtigkeit und Temperatur der Beblasungsluft keine relevanten Parameter darstellen. Es sind Feuchtigkeitswerte der Beblasungsluft zwischen 0 g/kg Luft und 30 g/kg Luft einsetzbar, und die Temperatur der Beblasungsluft kann zwischen 10°C und 30°C liegen (dem Fachmann ist bekannt, dass für ein gegebenes Feuchtigkeitssoll der Beblasungsluft eine minimale Lufttemperatur, die einer relativen Feuchte von 100% entspricht, nicht unterschritten werden kann)
   Die Geschwindigkeit der Beblasungsluft im Luftspalt ist niedriger als bei der Herstellung von derzeit kommerziell erhältlichen Lyocell-Fasern und soll unter 3 m/sec, bevorzugt bei etwa 1 - 2 m/sec liegen.
4. iv) Verzug im Luftspalt: Der Wert des Verzuges im Luftspalt (Quotient aus der Abzugsgeschwindigkeit aus dem Spinnbad zur Extrusionsgeschwindigkeit aus der Düse) soll unter 7 liegen. Erzielbar ist ein geringer Verzug bei definiertem Titer der Faser durch den Einsatz von Düsen geringen Lochdurchmessers. Einsetzbar sind Düsen mit einem Lochdurchmesser von ≤ 100 µm, bevorzugt werden Düsen mit einem Lochdurchmesser zwischen 40µm und 60 µm.
5. v) Spinntemperatur: Das Spinnen muss bei möglichst hoher Temperatur erfolgen, begrenzt nur durch die Thermostabilität des Lösungsmittels. Sie darf jedoch einen Wert von 130°C nicht unterschreiten.
6. vi) Die Spinnbadtemperatur kann zwischen 0°C und 40°C betragen, bevorzugt sind Werte von 0°C bis 10°C.
7. vii) Während des Transports der Faser vom Spinnbad in die Nachbehandlung und während der Nachbehandlung sollten entsprechend der WO 97/33020 die Filamente einer Zugbeanspruchung in Längsrichtung von nicht mehr als 5,5 cN/tex ausgesetzt werden.

Apart from the selection of the suitable pulp composition, the spinning conditions for producing the fiber according to the invention are of particular importance:

1. i) The spinning mass flow rate should be between 0.01 and 0.05 g / nozzle hole / min, preferably between 0.015 and 0.025 g / nozzle hole / min.
2. ii) Air gap length: The procedure for producing the fiber according to the invention differs from the prior art ( WO 95/02082 . WO 97/38153 ) in that the air gap length is not a relevant parameter. Already from 20 mm air gap fibers of the invention are obtained.
3. iii) Climate in the air gap: Here again, the production of the fiber according to the invention differs from the prior art ( WO 95/02082 . WO 97/38153 ) that moisture and temperature of the blown air are not relevant parameters. Humidity values of the blowing air between 0 g / kg air and 30 g / kg air can be used, and the temperature of the blowing air can be between 10 ° C and 30 ° C (those skilled in the art will know that for a given moisture level of the blowing air a minimum air temperature that does not fall below a relative humidity of 100%)
   The speed of the blowing air in the air gap is lower than in the production of currently commercially available lyocell fibers and should be less than 3 m / sec, preferably about 1-2 m / sec.
4. iv) Delay in the air gap: The value of the delay in the air gap (quotient of the withdrawal speed from the spin bath to the extrusion speed from the nozzle) should be less than 7. Achievable is a small distortion at a defined fiber titer through the use of small hole diameter nozzles. Applicable are nozzles with a hole diameter of ≤ 100 microns, preferred are nozzles with a hole diameter between 40 .mu.m and 60 .mu.m.
5. v) spinning temperature: The spinning must be carried out at the highest possible temperature, limited only by the thermostability of the solvent. However, it must not fall below a value of 130 ° C.
6. vi) The spinning bath temperature can be between 0 ° C and 40 ° C, preferred values are from 0 ° C to 10 ° C.
7. (vii) During the transport of the fiber from the spinning bath to the aftertreatment and during the aftertreatment, it is recommended that WO 97/33020 the filaments are subjected to a tensile stress in the longitudinal direction of not more than 5.5 cN / tex.

It has been found that, while maintaining the above parameters, reproducible lyocell fibers are obtained which satisfy the relations according to the invention with respect to the two Höller factors F1 and F2 and thus have "viscose-like" properties.

The present invention also relates to a fiber bundle containing a plurality of fibers according to the invention. By "fiber bundle" is meant a plurality of fibers, e.g. a plurality of staple fibers, a strand of continuous filaments or a bale of fibers.

Measurement Methods: Testing of textile-mechanical properties:

The determination of the titer of the fibers (linear density) was carried out according to the BISFA regulation " Testing methods viscose, modal, lyocell and acetate staple fibers and tows "Edition 2004 Chapter 6 with the help of a vibroscope design Lenzing Technik ,

The determination of the tensile force (breaking tenacity), the elongation at break, conditioning and wet and the wet modulus was carried out according to the above BISFA regulation Chapter 7 with the aid of a tensile tester Lenzing Vibrodyn (device for tensile tests on single fibers at constant deformation speed) ,

The loop strength was determined in accordance with DIN 53843 Part 2 as follows: The titers of the two fibers used for the test are determined on a vibroscope. For the determination of the loop strength, the first fiber is formed into a loop and clamped with both ends in the biasing weight (size of the bias weight according to the above BISFA regulation Chapter 7). The second fiber is drawn into the loop of the first fiber and the ends are clamped in the top clamp (gauge head) of the tensile tester so that the loop is in the middle of the two clamps. After settling the preload, the lower clamp is closed and the tensile test is started (clamping length 20 mm, pulling speed 2 mm / min). It must be ensured that the fiber break occurs at the loop of the loop. As titer-related Loop strength, the maximum tensile force value obtained is divided by the smaller of the two fiber titres.

The knot strength was determined in accordance with DIN 53842 Part 1 as follows: A loop is formed from the fiber to be tested, an end of the fiber is pulled through the loop, thus forming a loose knot. The fiber is clamped in the upper clamp of the tensile tester in such a way that the knot is midway between the clamps. After settling the preload, the lower clamp is closed and the tensile test is started (clamping length 20 mm, pulling speed 2 mm / min). For the evaluation, only results are used, where the fiber is actually torn at the node.

Determination of the fibrillation behavior according to the wet scrub method:

It became the in the publication Helfried Stöver: " For Faserassscheuerung of viscose fibers "Faserforschung and Textiltechnik 19 (1968) Heft 10, page 447-452 method described.

• Gerät: Scheuermaschine Delta 100 der Fa. Lenzing Technik Instruments
  Abweichend von der oben zitierten Publikation wird die Stahlwelle während der Messung in Längsrichtung kontinuierlich verschoben, um eine Rillenbildung im Filamentstrumpf zu vermeiden.
• Bezugsquelle Filamentstrumpf: Fa. Vom Baur GmbH & KG. Marktstraße 34, D-42369 Wuppertal
• Prüfbedingungen:
  • Durchflussmenge Wasser: 8,2 ml/min
  • Umdrehungsgeschwindigkeit: 500 U/min
  • Scheuerwinkel: 40° für Titer 1,3 dtex, 50° für Titer 1,7 dtex, 50° für Titer 3,3 dtex
  • Vorspann gewicht: 50 mg für Titer 1,3 dtex, 70 mg für Titer 1,7 dtex, 150 mg für Titer 3,3 dtex

The principle is based on the scrubbing of individual fibers in the wet state by means of a rotating steel shaft, which is coated with a Viskosefilamentstrumpf. The stocking is constantly wetted with water. The number of revolutions until the fiber is chafed and the preload weight triggers a contact is determined and related to the respective fiber titer.

• Apparatus: Scrubber Delta 100 from Lenzing Technik Instruments
  Notwithstanding the publication cited above, the steel shaft is continuously displaced in the longitudinal direction during the measurement, in order to avoid groove formation in the filament sock.
• Source of supply Filamentstrumpf: Fa. Vom Baur GmbH & KG. Marktstrasse 34, D-42369 Wuppertal
• test conditions:
  • Flow rate of water: 8.2 ml / min
  • Rotation speed: 500 rpm
  • Scrub angle: 40 ° for titer 1.3 dtex, 50 ° for titer 1.7 dtex, 50 ° for titer 3.3 dtex
  • Starting weight: 50 mg for titer 1.3 dtex, 70 mg for titer 1.7 dtex, 150 mg for titer 3.3 dtex

Determination of abrasion resistance of Martindale fabrics:

Methodology according to the standard "Determination of scrub resistance of textile fabrics using the Martindale method - Part 2: Determination of sample destruction (ISO 12947-2: 1998 + Cor. 1: 2002; German version EN ISO 12947-2: 1998 + AC: 2006 ).

Examples:

The pulps or pulp mixtures described below in Table 1 were processed into spinning masses of the composition listed in Table 2 and by a spinning process according to WO 93/19230 under the conditions of Table 2 to fibers having a titer of about 1.2 to about 1.6 dtex spun.

• der Spinnmasseausstoß mit 0,02 g/Loch/min
• der Luftspalt mit 20 mm
• die Feuchte der Beblasungsluft mit 8 - 12 g H₂O/kg Luft
• die Temperatur der Beblasungsluft mit 28 - 32°C
• die Geschwindigkeit der Beblasungsluft im Luftspalt mit 2 m/sec

Constant parameters not specified in the table are:

• the spin mass output at 0.02 g / hole / min
• the air gap with 20 mm
• the humidity of the blown air with 8 - 12 g H ₂ O / kg air
• the temperature of the blowing air at 28 - 32 ° C
• the speed of the blowing air in the air gap with 2 m / sec

The textile mechanical data of the obtained fibers are given in Table 3. The Höller factors calculated from the textile data, the wet abrasion value and the flexibility of the fibers are shown in Table 4. The results clearly show the influence of the pulp and the special importance of the spinning temperature. Table 1: cellulose code Intrinsic viscosity Alpha content Proportion DP <50 DP> 2000 ml / g % % Solucell 250 So 250 270 91.8 1.3 2.8 Borregard derivative HV Bo HV 1030 nb 1.4 49.1 Saiccor Sai 383 90.4 6.6 14.9 Borregard derivative VHV Bo VHV 1500 92.7 nb nb Solucell 400 So 400 415 94.9 1.9 11.8 Cotton Linters low MW Co LV 396 97.1 0.6 0 Cotton Linters high MW Co HV 2030 99.1 0 98.3 Recycled cotton fiber (reclaimed cotton fibers) low MW RCF LV 423 97.1 0.45 7.7 Recycled cotton fiber (reclaimed cotton fibers) high MW RCF HV 1840 97.8 0 68.7

Tabelle 3: Titer FFk FDk FFn FDn NM SFk KFk dtex cN/tex % cN/tex % cN/tex, 5% cN/tex cN/tex Beispiel 1 1,37 21,8 15,2 16,7 22,8 4,2 14,8 21,3 Beispiel 2 1,37 25,1 21,5 17,8 28,2 3,9 15,7 23,3 Beispiel 3 1,37 26,4 17,4 19,0 22,2 4,8 16,3 23,3 Beispiel 4 1,37 26,3 16,5 20,8 22,8 5,4 17,5 25,1 Beispiel 5 1,36 26,0 14,0 17,5 20,5 4,7 14,5 22,7 Beispiel 6 1,23 24,5 19,0 18,7 25,5 4,4 16,1 22,5 Beispiel 7 1,34 24,7 17,5 20,0 24,4 5,5 16,7 24,1 Beispiel 8 1,54 26,4 16,1 19,5 21,7 4,7 17,4 23,6 Beispiel 9 1,29 27,5 14,9 20,5 21,0 5,8 20,6 24,9 Beispiel 10 1,37 24,8 17,8 19,4 24,2 4,5 19,1 23,6 Beispiel 11 1,34 21,3 14,1 14,9 22,8 3,6 11,5 19,2 Beispiel 12 1,30 24,1 15,2 15,4 19,2 4,4 10,2 19,4 Beispiel 13 1,37 22,9 15,9 18,1 22,7 4,4 11,1 20,3 Beispiel 14 1,30 25,3 14,6 19,4 21,8 5,0 12,0 20,5 Beispiel 15 1,30 27,5 16,9 22,7 22,8 6,0 13,2 23,8 Beispiel 16 1,36 24,6 16,0 18,5 23,9 4,2 14,8 22,4 Beispiel 17 1,32 23,1 16,5 17,9 24,5 4,0 14,1 20,9 Vergleichsbeispiel 1 1,30 28,8 15,0 21,1 23,6 5,3 20,9 25,2 Vergleichsbeispiel 2 1,43 27,7 11,1 21,6 16,1 8,1 16,7 25,0 Vergleichsbeispiel 3 1,31 30,1 13,5 22,3 16,4 6,9 11,3 21,1 Vergleichsbeispiel 4 kommerzielle Lyocell-Faser 1,37 39,3 13,6 34,9 18,6 10,6 18,9 31,7 Tabelle 4 Höller-Faktor Höller-Faktor Nassscheuerwert Flexibilität F 1 F 2 Umdrehungen bis Bruch FDk/FFk Beispiel 1 -0,05 3,20 1951 0,70 Beispiel 2 -0,45 4,39 1947 0,86 Beispiel 3 0,27 4,22 664 0,66 Beispiel 4 0,51 4,88 370 0,63 Beispiel 5 0,40 3,33 244 0,54 Beispiel 6 -0,12 4,16 1427 0,78 Beispiel 7 -0,07 5,02 1455 0,71 Beispiel 8 0,42 4,53 511 0,61 Beispiel 9 0,84 5,61 303 0,54 Beispiel 10 0,17 5,15 635 0,72 Beispiel 11 -0,28 1,82 336 0,66 Beispiel 12 -0,04 1,45 585 0,63 Beispiel 13 -0,09 2,06 410 0,70 Beispiel 14 0,27 2,36 312 0,58 Beispiel 15 0,52 3,49 443 0,62 Beispiel 16 0,08 3,59 1153 0,65 Beispiel 17 -0,14 3,13 821 0,71 Vergleichsbeispiel 1 1,21 5,94 332 0,52 Vergleichsbeispiel 2 1,45 4,16 125 0,40 Vergleichsbeispiel 3 1,05 2,17 30 0,45 Vergleichsbeispiel 4 kommerzielle Lyocell-Faser 2,72 6,17 40 0,34 The pulps "RCF LV" and "RCF HV" have been prepared according to the teaching of the publication "Process for pretreating reclaimed cotton fibers used in the production of molded bodies from regenerated cellulose" (Research Disclosure, www.researchdisclosure.com, database number 609040, digitally published on December 11, 2014).

Table 3: titres FFk FDk FFn FDn NM SFk KFK dtex CN / tex % CN / tex % cN / tex, 5% CN / tex CN / tex example 1 1.37 21.8 15.2 16.7 22.8 4.2 14.8 21.3 Example 2 1.37 25.1 21.5 17.8 28.2 3.9 15.7 23.3 Example 3 1.37 26.4 17.4 19.0 22.2 4.8 16.3 23.3 Example 4 1.37 26.3 16.5 20.8 22.8 5.4 17.5 25.1 Example 5 1.36 26.0 14.0 17.5 20.5 4.7 14.5 22.7 Example 6 1.23 24.5 19.0 18.7 25.5 4.4 16.1 22.5 Example 7 1.34 24.7 17.5 20.0 24.4 5.5 16.7 24.1 Example 8 1.54 26.4 16.1 19.5 21.7 4.7 17.4 23.6 Example 9 1.29 27.5 14.9 20.5 21.0 5.8 20.6 24.9 Example 10 1.37 24.8 17.8 19.4 24.2 4.5 19.1 23.6 Example 11 1.34 21.3 14.1 14.9 22.8 3.6 11.5 19.2 Example 12 1.30 24.1 15.2 15.4 19.2 4.4 10.2 19.4 Example 13 1.37 22.9 15.9 18.1 22.7 4.4 11.1 20.3 Example 14 1.30 25.3 14.6 19.4 21.8 5.0 12.0 20.5 Example 15 1.30 27.5 16.9 22.7 22.8 6.0 13.2 23.8 Example 16 1.36 24.6 16.0 18.5 23.9 4.2 14.8 22.4 Example 17 1.32 23.1 16.5 17.9 24.5 4.0 14.1 20.9 Comparative Example 1 1.30 28.8 15.0 21.1 23.6 5.3 20.9 25.2 Comparative Example 2 1.43 27.7 11.1 21.6 16.1 8.1 16.7 25.0 Comparative Example 3 1.31 30.1 13.5 22.3 16.4 6.9 11.3 21.1 Comparative Example 4 commercial lyocell fiber 1.37 39.3 13.6 34.9 18.6 10.6 18.9 31.7 Höller factor Höller factor Wet abrasion value flexibility F 1 F 2 Turns until break FDk / FFk example 1 -0.05 3.20 1951 0.70 Example 2 -0.45 4.39 1947 0.86 Example 3 0.27 4.22 664 0.66 Example 4 0.51 4.88 370 0.63 Example 5 0.40 3.33 244 0.54 Example 6 -0.12 4.16 1427 0.78 Example 7 -0.07 5.02 1455 0.71 Example 8 0.42 4.53 511 0.61 Example 9 0.84 5.61 303 0.54 Example 10 0.17 5.15 635 0.72 Example 11 -0.28 1.82 336 0.66 Example 12 -0.04 1.45 585 0.63 Example 13 -0.09 2.06 410 0.70 Example 14 0.27 2.36 312 0.58 Example 15 0.52 3.49 443 0.62 Example 16 0.08 3.59 1153 0.65 Example 17 -0.14 3.13 821 0.71 Comparative Example 1 1.21 5.94 332 0.52 Comparative Example 2 1.45 4.16 125 0.40 Comparative Example 3 1.05 2.17 30 0.45 Comparative Example 4 commercial lyocell fiber 2.72 6.17 40 0.34

The position of the examples / comparative examples in the Höller diagram and the diagram area claimed according to the invention are shown in FIG. 3. Therein, examples 1 to 17 according to the invention are indicated by their respective numbers, and comparative examples 1 to 4 are each preceded by a "V".

Comparative Example 1 demonstrates that, if all production parameters except the spinning temperature, which is 122 ° C below the required value of at least 130 ° C, with the parameters for producing the fiber according to the invention, the object of the invention is not achieved.

Comparative Example 2 demonstrates that if all the production parameters, with the exception of the delay, which is higher than the required value of 9.64 with 9.64, coincide with the parameters for producing the fiber according to the invention, the object according to the invention is not achieved.

Comparative Example 3 demonstrates the importance of the pulp. If all manufacturing parameters except for the pulp composition, with a Single pulp does not have the required proportion of very high and low molecular weight, consistent with the parameters for producing the fiber according to the invention, the object of the invention is not achieved.

Comparative Example 4 shows the properties and the position in the Höller diagram of a commercial lyocell fiber (Tencel® from Lenzing AG)

Processing example:

A 130 kg bale of a fiber 1.3 dtex / 38 mm according to Example 11 was processed into a ring yarn Nm 50. From this yarn, a single jersey basis weight 150 g / m2 was produced. A sample of this single jersey was stained for 45 min with 4% Novacronmarine FG, liquor ratio 1:30 at 60 ° C in the laboratory jet and then subjected to 15 household washes at 60 ° C.

Table 5 shows the scrub and wash performance of this single jersey as compared to a fabric of the same construction of a commercial viscose or lyocell fiber. Table 5: Fiber according to Example 11 Viscose 1.3 dtex Lyocell standard 1.3 dtex Scouring Martindale tours until hole formation 57 500 58 750 15,500 washing trial Gray scale * Note after 1st wash 4-5 4 3-4 Note after 5th wash 4-5 4 1 Note after 10th wash 3 4-5 2 Note after 15. laundry 2-3 4-5 1 * Grades from 1 to 5, the best grade is 5

Claims (7)

1. A cellulosic fibre of the Lyocell type which has a titre of from 0.8 dtex to 3.3 dtex and is characterized by the following relationships:

   Höller factor F2 ≥ 1, preferably ≥ 2

   Höller factor F1 ≥ -0.6

   Höller factor F2 ≤ 6 and

   Höller factor F2 minus 4.5*Höller factor F1 ≥ 1, preferably ≥ 3.
2. A fibre according to claim 1, characterized by a wet abrasion resistance amounting to between 300 and 5000 revolutions.
3. A fibre according to claim 1 or 2, characterized by a flexibility of between 0.55 and 1.00.
4. A fibre according to any of the preceding claims, wherein a single jersey 150 g/m2 produced from a ring yarn Nm 50/1 of said fibre exhibits an abrasion resistance according to Martindale of between 30 000 and 60 000 tours up to the point of hole formation.
5. A fibre according to any of the preceding claims, characterized in that it is produced according to the amine oxide process.
6. A fibre according to any of the preceding claims, characterized in that it is produced from a mixture of at least two different pulps.
7. A fibre bundle comprising a plurality of fibres according to any of the preceding claims.

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