Method for preparing cellulose functional fiber having high ion exchange capacity and cellulose functional fiber

Abstract

The present invention relates to a method for preparing a cellulose functional fiber having a high ion exchange capacity, a cellulose functional fiber prepared by the method, a textile product comprising the cellulose functional fiber, and clothing or furniture comprising the cellulose functional fiber and / or the textile product. The cellulose functional fiber prepared according to the present invention is characterized in that it comprises an extracted plant material having polymer-bound uronic acid contained therein.

Description

[0001] The present invention relates to a method for preparing cellulose functional fibers with high ion exchange capacity, cellulose functional fibers prepared by the method, textile products containing the cellulose functional fibers, and clothing or furniture containing the cellulose functional fibers and / or the textile products. Prior art

[0002] Cellulose fibers can be manufactured artificially from pulp. Technically, such cellulose fibers can be manufactured as regenerated fibers, the most important representatives of which include viscose, modal, lyocell and cupro. Lyocell is a cellulose regenerated fiber that is produced according to the so-called lyocell process, a direct dissolution method with N-methylmorpholine-N-oxide monohydrate (NMMO) as solvent. Cellulose fibers produced according to the lyocell process have excellent physical properties, which allow the integration of foreign materials into the textile fibers in large proportions.

[0003] These foreign materials can be, in particular, other polysaccharides, for example cellulose derivatives, chitin, xylan or starch, of which polysaccharides containing uronic acid have proven to be particularly interesting. These cellulose fibers can be used in particular in medicine, in water treatment and in functional clothing. In the form of monomers and oligomers, uronic acid is completely unsuitable as a material for textile fibers because it is water-soluble.

[0004] DE 10009034A1 discloses a method for producing a cellulose molded body with reduced, specifically adjustable fibrillation. The method comprises transferring a suspension consisting of cellulose and aqueous N-methylmorpholine-N-oxide into an extrusion solution, extruding the extrusion solution through a die and through an air gap into a precipitation bath, and washing and crosslinking the precipitated molded body, wherein an oxidized second polysaccharide is also used and the cellulose is crosslinked with the oxidized second polysaccharide. Water-soluble homopolysaccharides and heteropolysaccharides can be used as the second polysaccharide, wherein examples of heteropolysaccharides include in particular pectin and algin.

[0005] WO2001 / 062844A1 describes a method for preparing a molded body with a low fibrillation tendency. The method comprises (a) mixing a biodegradable polymer selected from cellulose, modified cellulose and mixtures thereof with a material from marine plants and / or from the shells of marine animals, wherein the material from marine plants and / or from the shells of marine animals is present in an amount of 0.1 to 30% by weight, based on the weight of the biodegradable polymer, (b) preparing a deformable material according to the lyocell process, (c) processing the material obtained in (b) into a molded body, and (d) post-treating the prepared molded body. The material from marine plants is preferably selected from seaweed, kelp and seaweed, wherein examples of seaweed include brown algae, green algae, red algae, blue algae and mixtures thereof.

[0006] WO 2003 / 012182 A1 describes a method for producing cellulose shaped bodies with a high retention capacity for aqueous liquids. The method comprises producing and extruding a deformable material according to the lyocell process, wherein, in addition to cellulose, the deformable material also contains a superabsorbent polymer obtained by polymerizing (a) 55 to 99.95% by weight of monomers carrying monoethylenically unsaturated carboxyl groups, (b) 0.05 to 5.0% by weight of at least one crosslinking agent, (c) 0 to 40% by weight of other monomers copolymerizable with (a) and (d) 0 to 30% by weight of a water-soluble grafting matrix. The grafting matrix may be, in particular, partially or completely saponified polyvinyl alcohol, polyacrylic acid, polyethylene glycol and polysaccharides, wherein, as specific examples of polysaccharides, in addition to cellulose, cellulose derivatives, starch, starch derivatives and xanthan gum, alginates are mentioned.

[0007] CN 103 194 826 A discloses a method for preparing a biodegradable blended yarn having antibacterial properties, good hygroscopicity and high yarn strength, which can be used in particular for the manufacture of clothing. The method comprises opening and cleaning, combing, roving, spun yarn and winding a suitable mixture, which mixture is composed of 10 to 80% by weight of alginate fibers, 10 to 80% by weight of pupa protein fibers and 10 to 80% by weight of bamboo fibers, wherein the alginate fibers are formed from sodium alginate, which is previously obtained by extracting seaweed with water as an extractant.

[0008] CN 108 065 459 A discloses a method for preparing a textile with good hygroscopicity, which is used for manufacturing thermal underwear. The method comprises spinning a mixture consisting of 40 to 60 parts by weight of cotton fiber, 20 to 40 parts by weight of lyocell bamboo fiber, 30 to 40 parts by weight of modal fiber, 25 to 30 parts by weight of spandex fiber, 25 to 45 parts by weight of alginate fiber and 5-15 parts by weight of cashmere, wherein the alginate fiber is formed by sodium alginate obtained by extracting seaweed with water as an extractant.

[0009] Generally, the polymer containing uronic acid also has ion exchange properties. However, in the scope of the direct dissolution method such as lyocell process, the ion exchange natural product is used for cellulose functional fibers and has various shortcomings, which makes stable process control difficult. Particularly, soluble components such as mineral salts and water-soluble organic substances (such as proteins, carbohydrates, lipids and dyes) are enriched in the working medium of the circulation operation (for example, in solvents such as N-methylmorpholine N-oxide). These undesirable components cause solvolysis or cause scaling or pollution in the system, and due to required cleaning measures, this causes throughput reduction and production cost increase. In addition, the undesirable component can have a negative impact on the quality of the prepared cellulose molded body.

[0010] Purpose of the Invention

[0011] The object of the present invention is therefore to provide a method for preparing cellulose functional fibers which largely avoids the above-mentioned disadvantages. In particular, the method should not have an adverse effect on the solvent cycle and the fiber manufacturing process and should be able to cost-effectively and efficiently prepare cellulose functional fibers with a high ion exchange capacity based on naturally occurring polymers. SUMMARY OF THE INVENTION

[0013] This object is achieved by means of the subject matter of the invention as defined in the claims.

[0014] Therefore, in a first aspect, the present invention relates to a method for preparing a cellulose functional fiber, comprising the following steps:

[0015] Providing a plant material containing polymer-bound uronic acid;

[0016] extracting the plant material with an extractant in such a way as to provide an extracted plant material containing polymer-bound uronic acid;

[0017] providing a spinning solution comprising cellulose and the extracted plant material containing polymer-bound uronic acid; and

[0018] The spinning solution is spun.

[0019] In a second aspect, the present invention relates to a cellulosic functional fiber prepared by the method described in the first aspect.

[0020] In a third aspect, the present invention relates to a textile product comprising the cellulosic functional fiber described in the second aspect.

[0021] In a fourth aspect, the present invention relates to clothing or furniture comprising the cellulosic functional fiber described in the second aspect and / or the textile product described in the third aspect. DETAILED DESCRIPTION OF THE INVENTION

[0023] In the context of the preparation method according to the invention, a plant material containing polymer-bound uronic acid is first provided. As used herein, the term "plant material" includes all naturally occurring plants and plant parts of terrestrial or marine origin, which contain polymer-bound uronic acid and should therefore already have a significant ion exchange capacity for cations.

[0024] Preferably, the plant raw material is selected from fruits, seeds, leaves, roots, stems and trunks, and particularly preferably includes pectin-containing plant parts or / and uronic acid-containing marine plants. Examples of pectin-containing plant parts include in particular citrus fruits and the fruit sequences of sunflowers, pears, apples, guavas, papayas, plums and currants. Residues (pomace) of juice manufacturing are also suitable. Examples of uronic acid-containing marine plants include in particular marine plants composed of uronic acid-containing polysaccharides, such as algae, kelp and seegrass. In this article, more preferably use algae, examples of which include brown algae, green algae, red algae, blue algae and mixtures thereof. Brown algae, in particular brown algae of the following genera are considered to be particularly preferred: Ascophylum, Durvillea, Ecklonia, Fucus, Laminaria, Lessonia and Macrocystis. Furthermore, it is particularly preferred according to the invention that the plant material is not mint or parts thereof, specific examples of mint including in particular spearmint, water mint, field mint and peppermint.

[0025] As used herein, the term "ion exchange capacity" refers to the amount of zinc ions in moles that can be bound per gram of fiber. The definition of zinc ions is derived from the assay method. Qualitatively, ion exchange capacity can also be transferred to other metal ions, so for example an increase in zinc ion capacity also means an increase in magnesium ion capacity, although not necessarily to the same extent.

[0026] In the next step of the preparation method of the present invention, the selected plant material is extracted with an extractant and optionally post-treated to remove water-soluble components such as mineral salts that can interfere with the spinning process, leaving only the water-insoluble skeleton structure of the plant. By removing mineral salts from the plant material, the active centers for ion exchange are unblocked, thereby further increasing the ion exchange capacity of the plant material. The post-treatment of the plant material is carried out by means of solid-liquid extraction, wherein the extractant preferably comprises water, an organic solvent or a mixture of water and at least one organic solvent. More preferably, the extractant is water or a mixture of water and at least one organic solvent, and particularly preferably a mixture of water and at least one organic solvent.

[0027] As organic solvents, in particular, protic solvents selected from alcohols, amines, amides and carboxylic acids, or / and aprotic polar solvents selected from ketones, lactones, lactams, nitriles, nitro compounds, tertiary carboxylic acid amides, sulfoxides, sulfones and carbonates are contemplated. Specific examples of protic solvents include methanol, ethanol, isopropanol, ethanolamine, ethylenediamine, formamide, formic acid, acetic acid and propionic acid, but are not limited to these. Specific examples of aprotic polar solvents include acetone, methyl ethyl ketone, γ-butyrolactone, N-methyl-2-5-pyrrolidone, acetonitrile, nitromethane, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, cyclopentane, dimethyl carbonate and ethylene carbonate.

[0028] If the extractant used is a mixture of water and at least one organic solvent, the proportion of the organic solvent is preferably 10 to 80% by weight, based on the total weight of the solvent mixture. The upper limit of the organic solvent proportion is naturally limited by the existing miscibility of the organic solvent with water. More preferably, the proportion of the organic solvent is 20 to 70% by weight, particularly preferably 30 to 60% by weight, based on the total weight of the solvent mixture.

[0029] The extraction itself can be carried out continuously or discontinuously. In the case of discontinuous extraction, the temperature range between 0 ° and the boiling point of the solvent / solvent mixture is used. For this purpose, for example, the plant material can be introduced into a Soxhlet tube and extracted with the aid of a device comprising a Soxhlet extractor under reflux of the solvent. In this way, after the extraction, the extracted plant material containing polymer-bound uronic acid is obtained, which is usually dried and ground for further processing. Surprisingly, the plant material obtained by means of the extraction can be finely ground very well.

[0030] As used herein, the term "extracted plant material containing polymer-bound uronic acid" therefore refers to the extraction residue obtained after extraction of the respective plant material with an extractant and which comprises the components of the plant material that are insoluble in the extractant. In contrast, by definition, the extract comprises those components of the plant material that are soluble in the extractant under the predetermined reaction conditions, such as mineral salts and water-soluble uronic acid derivatives including alginic acid and sodium alginate.

[0031] In the last step of the preparation method of the present invention, the extracted plant material containing polymer-bound uronic acid is combined with cellulose to provide a spinning solution, which is spun into cellulose functional fibers according to known methods. In particular, the present invention provides the preparation of cellulose functional fibers according to the Lyocell process, wherein the extracted plant material containing polymer-bound uronic acid is added, for example, to a spinning solution containing cellulose and N-methylmorpholine-N-oxide monohydrate, and then the obtained spinning solution is spun into filaments, fibers or films under suitable conditions. Accordingly, it is particularly preferred according to the present invention that the spinning solution neither contains extracts produced as by-products within the scope of plant material extraction, nor does it contain materials obtained by post-treatment or cleaning of the extract. By not further using the extract, the fiber preparation process can be simplified, and the production cost can be significantly reduced due to the expansion of the interval between maintenance work and the increase in production volume.

[0032] The proportion of the extracted plant material containing polymer-bound uronic acid in the spinning solution to be spun can be adjusted as desired by a person skilled in the art according to the respective requirements of the final textile product, but is preferably 0.1 to 15% by weight, based on the weight of the cellulose contained in the spinning solution. More preferably, the proportion of the extracted plant material containing polymer-bound uronic acid in the spinning solution is 1.0 to 10% by weight, particularly preferably 2.5 to 7.5% by weight, based on the weight of the cellulose contained in the spinning solution.

[0033] If the solvent added to the spinning solution (e.g. N-methylmorpholine-N-oxide monohydrate) is recycled, the enrichment of the system with mineral salts or soluble organic components can be largely avoided due to the extraction of the plant raw material with a suitable extractant according to the invention, thereby reducing the maintenance work caused by cleaning and also increasing the production output. In addition, the method can be easily applied to existing cellulose fiber production plants.

[0034] The cellulose functional fibers prepared by the method of the present invention can be advantageously used to manufacture yarns, twisted yarns, ropes, textiles, knitted fabrics, crocheted fabrics, braided fabrics, nonwovens, felts and other textile products, wherein the fibers impart their functions to the entire textile product. The textile products can be further processed in an appropriate manner and can be used in particular to manufacture clothing, furniture (especially as coverings) or carpets. Compared with cellulose functional fibers containing a certain proportion of untreated natural products, textile products containing or made of the fibers are characterized by similarly high wearing comfort and better ion binding properties. In addition, the cellulose functional fibers prepared by the method of the present invention also have properties similar to those of fibers conventionally prepared according to the lyocell process, and they can be processed into fabrics in the same technical manner.

[0035] These properties may be attributed to the fact that the cellulose functional fibers prepared according to the invention contain polymer-bound uronic acids such as α-L-guluronic acid and β-D-mannuronic acid fixed on cellulose, whose pKa values ​​are surprisingly well coordinated with the pH value of the skin, and the uronic acid active centers responsible for ion exchange become easily accessible through targeted separation of mineral salts, which generally leads to an ion exchange capacity of at least 60 μmol / g. Preferably, the ion exchange capacity of the cellulose functional fibers prepared according to the invention is at least 65 μmol / g, particularly preferably at least 70 μmol / g.

[0036] Surprisingly, the ion exchange capacity of the cellulose functional fibers described herein can be further increased, at least temporarily, i.e. temporarily or permanently, by specifically supplying the spinning solution itself or the cellulose functional fibers obtained after spinning the spinning solution with an alkaline earth metal salt or zinc salt having a water solubility of at least 100 g / l at 20°C, preferably a magnesium salt, calcium salt or zinc salt having a water solubility of at least 100 g / l at 20°C, more preferably a magnesium salt or calcium salt having a water solubility of at least 100 g / l at 20°C, particularly preferably calcium chloride.

[0037] If such alkaline earth metal salt or zinc salt, preferably such magnesium salt, calcium salt or zinc salt, more preferably such magnesium salt or calcium salt, and particularly preferably calcium chloride are directly added to the spinning solution, the ion exchange capacity of the cellulose functional fiber is significantly increased to usually at least 75 μ mol / g. For this purpose, the spinning solution can, for example, further contain 0.5 to 5% by weight of alkaline earth metal salt or zinc salt, preferably magnesium salt, calcium salt or zinc salt, more preferably magnesium salt or calcium salt and particularly preferably calcium chloride, based on the weight of the cellulose contained in the spinning solution. In the case of using alkaline earth metal salts such as calcium chloride or zinc salts, the proportion of salt in the spinning solution is preferably 1.0 to 3.5% by weight, particularly preferably 1.5 to 3.0% by weight, based on the weight of the cellulose contained in the spinning solution. By washing the cellulose functional fiber prepared in this way with household common washing powder, the ion exchange capacity of the fiber can even be further increased.

[0038] Alternatively, the cellulose functional fiber obtained after spinning the spinning solution can be treated (e.g., immersed) with an aqueous solution of an alkaline earth metal salt or zinc salt having a water solubility of at least 100 g / l at 20°C, preferably an aqueous solution of a magnesium salt, calcium salt or zinc salt having a water solubility of at least 100 g / l at 20°C, more preferably an aqueous solution of a magnesium salt or calcium salt having a water solubility of at least 100 g / l at 20°C, and particularly preferably an aqueous solution of calcium chloride. As a result, the initial ion exchange capacity of the cellulose functional fiber is first significantly increased to generally at least 80 μmol / g. However, the ion exchange capacity of this cellulose functional fiber decreases to the level of untreated fibers with additives added as the number of washings increases. The concentration of the alkaline earth metal salt or zinc salt, preferably a magnesium salt, a calcium salt or a zinc salt, more preferably a magnesium salt or a calcium salt, and particularly preferably calcium chloride in the aqueous solution can be adjusted as needed by the technician, however, preferably 2 to 8% by weight, more preferably 4 to 6% by weight.

[0039] Hereinafter, the present invention is described in more detail with the aid of Examples. Unless otherwise specified, the chemicals used in the Examples were each obtained from Sigma-Aldrich. Example

[0040] Example 1

[0041] Dried algae flour of the brown algae Laminaria genus (manufacturer: smartfiber AG) was extracted with the aid of a Soxhlet extractor. For this purpose, 1 g of algae flour was weighed into a Soxhlet tube and extracted under reflux for 2 hours. As extractants, water (ultrapure water) was used on the one hand and a water / ethanol mixture with a mass ratio of 70:30 on the other hand. The seaweed material obtained after the extraction was dried in each case and then analyzed for selected chemical elements with the aid of elemental analysis.

[0042] Here, the contents of carbon (C), hydrogen (H), nitrogen (N) and sulfur (S) were determined in each case on a Euro Elementaranalysator from HEKAtech GmbH according to the manufacturer's instructions.

[0043] The determination of the contents of chlorine (Cl) and iodine (I) was carried out on an ICS-900 ion chromatography system from Thermo Fisher Scientific Inc in accordance with DIN EN ISO 10304-1:2009-07 for chlorine and for iodine.

[0044] The contents of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg) and iron (Fe) were determined according to DIN EN ISO 11885:2009-09 in the iCAP of Thermo Fisher Scientific Inc. TMThe measurements were carried out on a 7400 ICP-OES analyzer.

[0045] The results of elemental analysis are presented in Tables 1 and 2.

[0046] Table 1

[0047]

[0048] Table 2

[0049]

[0050] Example 2

[0051] Preparation of 6 wt% Cuoxam-DP 615 cellulose (Manufacturer: Fabriker AB), 52.5 wt. % N-methylmorpholine-N-oxide monohydrate (NMMO) (manufacturer: OQEMA AG) and 41.5 wt. % water. The suspension was sheared and the water evaporated at a temperature of 95° C. and a pressure of 70 mbar to produce a solution, which was then pressed through a fiber spinneret, passed through an air gap into a precipitation bath and then drawn off. The resulting cellulose functional fiber (fiber 1: lyocell fiber) was then solvent-washed, spun, cut and dried.

[0052] Example 3

[0053] The method for preparing cellulose functional fibers according to the Lyocell process described in Example 2 was repeated, except that 5 wt % (based on the weight of cellulose contained in the spinning solution) of the untreated algae powder used as a raw material in Example 1 was added to the spinning solution. After spinning and post-treatment, cellulose functional fibers containing uronic acid (fiber 2) were obtained.

[0054] Example 4

[0055] The method for preparing cellulose functional fibers according to the Lyocell process described in Example 2 was repeated, except that 5 wt % (based on the weight of cellulose contained in the spinning solution) of the algae powder extracted with water obtained in Example 1 was added to the spinning solution. After spinning and post-treatment, cellulose functional fibers containing uronic acid (fiber 3) were obtained.

[0056] Example 5

[0057] The method for preparing cellulose functional fibers according to the Lyocell process described in Example 2 was repeated, except that 5 wt% (based on the weight of cellulose contained in the spinning solution) of the algae powder extracted with water / ethanol in a mass ratio of 70:30 obtained in Example 1 was added to the spinning solution. After spinning and post-treatment, cellulose functional fibers containing uronic acid (fiber 4) were obtained.

[0058] The cellulose functional fibers produced in Examples 2 to 5 were then examined for their coloration, their fabric physical values, their water-retaining capacity, and their ion-exchange capacity. It was found here that the different cellulose functional fibers had no difference in their coloration.

[0059] The fiber fineness is determined according to DIN EN ISO 1973:1995-12.

[0060] The determination of the maximum tensile force, the coefficient of variation of the maximum tensile force, the elongation at maximum force, the breaking strength, the coefficient of variation of the breaking strength, the fineness-dependent loop breaking strength (Schlingenreiβkraft) and the A modulus were each carried out in accordance with DIN EN ISO 5079:1996-02 on a Z005 universal testing machine from ZwickRoell GmbH & Co. KG.

[0061] The water retention capacity is determined according to DIN 53814:1974-10.

[0062] The ion exchange capacity was determined on the washed and dried fibers, following steps 1 to 4 as described in more detail below.

[0063] Step 1: De-ashing

[0064] To remove metal ions, about 5 g of chopped fibers were stirred in about 200 ml of 0.1 to 0.2 N hydrochloric acid with an Ultra-Turrax stirrer and stirred with the aid of a magnetic stirrer for 2 hours. The slurry was then drawn off through a G2 glass frit, neutrally washed with water and air-dried. The dry content of these deashed, air-dried fibers was determined.

[0065] Step 2: Reaction with zinc acetate

[0066] To exchange hydrogen ions for zinc ions, 1 g of deashed fiber with known dry content (weighed mE) was mixed with 50 ml of 0.02 N zinc acetate solution in a conical flask and closed with a stopper. The fiber sample remained in the zinc acetate solution for 24 hours and during this time was shaken for at least 5 hours (shaker).

[0067] Step 3: Titration

[0068] In order to determine the reduction in the zinc ion concentration in the added zinc acetate solution, the fiber suspension was shaken vigorously again before titration and sucked off through a dry G3 glass frit. 5 ml of NH3 / NH4Cl buffer solution (pH 10) was added to 25 ml of the filtrate and the indicator titration (Eriochromeschwarz T) was added until the solution turned reddish purple. Titrate with 0.01 N complexone solution until the color turned blue (consumption b). In a separate sample, 25 ml of the used zinc acetate solution (consumption a) was titrated with 0.01 N complexone solution under the same conditions.

[0069] Step 4: Calculation of ion exchange capacity.

[0070] The ion exchange capacity of each cellulose functional fiber is calculated according to the following formula:

[0071]

[0072] Where m E = weight [g], TG = dry content [%], b = complex ketone consumption of sample solution [ml], and a = complex ketone consumption of zinc acetate solution [ml].

[0073] The results of the determination of the fabric physical values, water retention capacity and ion exchange capacity are given in Table 3.

[0074] Table 3

[0075]

[0076] As can be seen from Table 3, the fabric physical parameters of the cellulose functional fibers with polymer-bound uronic acid added in the form of algae powder are all within the common variation range of lyocell fibers. In terms of ion exchange capacity, it has been shown that the addition of 5% by weight of algae powder (based on the weight of cellulose contained in the spinning solution) has led to a significant increase in ion exchange capacity. In the case of using untreated algae powder, the ion exchange capacity increased to 7 times the value of fiber 1 not mixed with algae powder (see fiber 2), in the case of using algae powder after extraction with water, the ion exchange capacity increased to 7.5 times (see fiber 3), and in the case of using algae powder after extraction with a water / ethanol mixture, it increased to 9 times (see fiber 4).

[0077] Example 6

[0078] The method for preparing cellulose functional fibers according to the Lyocell process described in Example 4 was repeated, except that 1.8% by weight (based on the weight of cellulose contained in the spinning solution) of calcium chloride was additionally added to the spinning solution. After spinning and post-treatment, cellulose functional fibers containing uronic acid (fiber 5) were obtained. The ion exchange capacity of this fiber was 78 μmol / g, which is about 10 times the value of fiber 1 not mixed with algal flour.

[0079] Example 7

[0080] The cellulose functional fibers obtained in Examples 2 to 6 were subjected to 25 household conventional washings with laundry detergent, and then their ion exchange capacities were re-examined. The results are shown in Table 4.

[0081] Table 4

[0082]

[0083] As can be seen from Table 4, the ion exchange capacity of conventional cellulose functional fibers prepared according to the Lyocell process and without uronic acid decreased after multiple washings (see Fiber 1). In contrast, the cellulose functional fibers mixed with algae flour each had a higher ion exchange capacity than the corresponding unwashed fibers after 25 household conventional washings (see Fibers 2 to 5). This may be attributed to the increased degree of fibrillation of the fibers, thereby making other active centers for ionic bonding accessible.

[0084] Example 8

[0085] The cellulose functional fibers obtained in Examples 3 to 5 were each treated (impregnated) with a 5 wt % aqueous solution of calcium chloride and then dried. The ion exchange capacity of the fibers obtained here was then examined before and after 25 household routine washings with a washing powder. The results are shown in Table 5.

[0086] Table 5

[0087]

[0088] As can be seen from Table 5, in the case where the cellulose functional fibers were impregnated with CaCl2, an immediate increase in ion exchange capacity was observed compared to the fibers that were not post-treated. However, the effect of this post-treatment was no longer significant after 25 washes with detergent.

Claims

1. A method for preparing a cellulose functional fiber, comprising the following steps: Providing a plant material containing polymer-bound uronic acid; extracting the plant material with an extractant in such a way as to provide an extracted plant material containing polymer-bound uronic acid; providing a spinning solution containing cellulose and the extracted plant material containing polymer-bound uronic acid; and Spinning the spinning solution, The extracted plant material containing polymer-bound uronic acid is an extraction residue obtained after extracting the plant material with an extractant, and contains components of the plant material that are insoluble in the extractant. wherein the extractant comprises water, an organic solvent or a mixture of water and at least one organic solvent, The organic solvent includes a protic solvent selected from alcohols, amines, amides and carboxylic acids, or / and an aprotic polar solvent selected from ketones, lactones, lactams, nitriles, nitro compounds, tertiary carboxamides, sulfoxides, sulfones and carbonates.

2. The method for preparing cellulose functional fibers according to claim 1, characterized in that: The plant material is selected from the group consisting of fruits, seeds, leaves, roots, stems and trunks.

3. The method for preparing cellulose functional fibers according to claim 1 or 2, characterized in that: The plant raw material is derived from marine plants and consists of polymer-bound uronic acid.

4. The method for preparing cellulose functional fibers according to any one of claims 1 to 2, characterized in that: The proportion of the extracted plant material containing polymer-bound uronic acid in the spinning solution is from 0.1 to 15% by weight, based on the weight of the cellulose contained in the spinning solution.

5. The method for preparing cellulose functional fibers according to any one of claims 1 to 2, characterized in that: The cellulose functional fiber is prepared according to the Lyocell process.

6. The method for preparing cellulose functional fibers according to any one of claims 1 to 2, characterized in that: The spinning solution furthermore contains 0.5 to 5% by weight, based on the weight of the cellulose contained in the spinning solution, of an alkaline earth metal salt or zinc salt having a water solubility of at least 100 g / l at 20° C.

7. The method for preparing cellulose functional fibers according to any one of claims 1 to 2, characterized in that: The method further comprises treating the cellulose functional fiber obtained by spinning the spinning solution with 2 to 8% of an aqueous solution of an alkaline earth metal salt or a zinc salt having a water solubility of at least 100 g / l at 20°C.

8. The method for preparing cellulose functional fibers according to claim 6, characterized in that: The alkaline earth metal salt or zinc salt having a water solubility of at least 100 g / l at 20° C. is calcium chloride.

9. The method for preparing cellulose functional fibers according to claim 7, characterized in that: The alkaline earth metal salt or zinc salt having a water solubility of at least 100 g / l at 20° C. is calcium chloride.

10. Cellulose functional fibers produced by the method according to any one of claims 1 to 9.

11. A textile product comprising the cellulose functional fiber according to claim 10.

12. The textile article according to claim 11, wherein the textile article is a yarn, a twisted yarn, a rope, a woven fabric, a knitted fabric, a crocheted fabric, a braided fabric, a non-woven fabric or a felt.

13. Clothing comprising the cellulosic functional fiber according to claim 10 and / or the textile product according to claim 11 or 12.

14. Furniture comprising the cellulose functional fiber according to claim 10 and / or the textile product according to claim 11 or 12.

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