Nonwoven fabrics, products containing same, and methods for producing nonwoven fabrics

Abstract

The present invention relates to nonwoven fabrics and fibrous monofilaments comprising cellulose-containing fibrous monofilaments, optionally with thermoplastic fibers or man-made cellulose fibers or non-wood-derived cellulose fibers or any mixture thereof. Additionally, the present invention relates to methods for preparing and using such fabrics and / or monofilaments.

Description

[Technical Field]

[0001] The present invention relates to a nonwoven fabric and an article comprising the nonwoven fabric. The present invention further relates to a method for producing fibrous monofilaments and a method for producing the nonwoven fabric. [Background technology]

[0002] Nonwoven fabrics are broadly defined as sheet or web structures formed from staple fibers (short fibers) and filaments (continuous fibers) bonded together by mechanical, thermal, or chemical processes. The term is used in the textile manufacturing industry to refer to fabrics, such as felt, that are neither woven nor knitted. Nonwoven fabrics are used in a variety of applications, including medical applications such as protective layers, surgical mask wipes, and wound dressings, gas filters, and other uses such as geotextiles, composites, diaper stock, insulation, packaging, and various wipes. Nonwoven fabrics can be disposable, have a limited lifespan, or be very durable. The properties and raw materials of nonwoven fabrics can be tailored for each use. The amount of nonwoven fabrics used worldwide is staggering. Recycled fabrics and oil-based materials are commonly used in nonwoven fabrics. One drawback of nonwoven fabrics is the environmental impact of oil-based materials such as polyester, acrylic, and nylon, and such fabrics are energy-intensive to produce and have low or no biodegradability.

[0003] Single-use or short-term use of disposable plastic products (SUPs) contributes to increased plastic waste in the environment. Disposable plastic products are more likely to end up in the ocean than reusable and biodegradable options. Global efforts exist to reduce the plastic burden in our environment. In this regard, the EU SUP Directive targets the vast majority of single-use plastics, aiming to reduce waste, support the development of a circular economy, and promote a sustainable future. One category of potentially problematic products are globally used disposable hygiene products such as towels, tampons, health bandages, and wet wipes, which contain nonwoven fabrics with plastic components.

[0004] However, various challenges exist with known solutions for providing more sustainable nonwoven fabrics and related products that are free of plastic components or at least have a reduced proportion of plastic components. In general, it can be said that the controllability of the properties that can be achieved using sustainable nonwoven fabrics, such as absorbency and resilience, tenacity, durability, among other properties, remains a challenge in some use cases and must also be considered for manufacturing methods of sustainable nonwoven fabrics that are implemented on an industrial scale.

[0005] Natural fibers such as cotton, linen, and hemp offer a more sustainable solution compared to plastic components to reduce the environmental impact of nonwovens. However, there remains a continuing need to find products that can be produced as sustainable nonwovens on an industrial scale, thereby reducing environmental impact, land use, and water consumption.

[0006] In some applications, fibrous monofilaments can replace, for example, cotton. Large-scale cotton cultivation requires large amounts of water resources. Cotton cultivation is widespread in areas where both water and food are already scarce. Cotton cultivation reduces the agricultural area available for food production, increases water consumption, and exacerbates food and water supply problems. Cotton use is unsustainable, and a replacement fiber source is needed. The properties and production methods of previously proposed paper yarns do not allow for the replacement of cotton.

[0007] There is a continuing need to obtain sustainable materials with desirable technical and mechanical properties for nonwoven and related products and their manufacturing processes. Summary of the Invention

[0008] The present invention at least alleviates one or more of the above-mentioned drawbacks or problems associated with existing solutions.

[0009] It is an object of the present invention to provide a nonwoven fabric that is suitable for multiple uses and has environmentally sustainable properties. It is a further object to provide products including the nonwoven fabric, as well as methods of manufacturing fibrous monofilaments and nonwoven fabrics.

[0010] The object of the present invention is achieved by a nonwoven fabric and a product comprising the nonwoven fabric, as well as a method for producing fibrous monofilaments and nonwoven fabrics, characterized by what is presented in the independent claims. Some advantageous embodiments of the invention are presented in the dependent claims.

[0011] One advantage of the nonwoven fabrics and fibrous monofilaments discussed in this disclosure is that their water footprint can be significantly lower compared to existing solutions. The use of pulp-based fibers also allows for the utilization and reuse of wood, pulp, and pulp waste. Furthermore, the water usage of wood-based textile fibers is significantly lower compared to, for example, cotton.

[0012] Another advantage of the nonwoven fabrics and fibrous monofilaments discussed in this disclosure is their good biodegradability. Further advantages of the present invention are described below. [Brief explanation of the drawings]

[0013] [Figure 1a] 1 shows the processability of the tested monofilaments of Example 1. [Figure 1b] The percentage elongation of the monofilaments tested is shown. [Figure 1c] The strength of the monofilaments tested is shown. [Figure 1d] The width (in micrometers) of the monofilament is indicated (marked as fiber in the figure). [Figure 1e] 1 shows the gel strength of the suspension used to prepare the monofilaments. [Figure 2a]1 illustrates the tensile strength (machine direction) of nonwoven fabrics comprising fibrous monofilament, lyocell, and BiCo described herein, with dry sheet measurements shown as solid lines and wet sheet measurements shown as dashed lines. [Figure 2b] 1 illustrates the tensile strength (cross direction) of nonwoven fabrics comprising fibrous monofilament, lyocell, and BiCo described herein, with dry sheet measurements shown as solid lines and wet sheet measurements shown as dashed lines. DETAILED DESCRIPTION OF THE INVENTION

[0014] In this disclosure, percentage values ​​relating to the amount or proportion of raw materials are weight percentages (wt %) of the dry monofilament / nonwoven unless otherwise indicated.

[0015] In this disclosure, the term nonwoven fabrics or nonwovens refers to sheet or web structures bonded together by mechanically, thermally, or chemically entangling fibers or monofilaments. Typically, they are in the form of sheets or layers, but other forms that can be used, for example, as absorbents, are also included. They can be made from a single material (such as the cellulose fibrous MFC monofilaments described herein) or from separate materials, such as filaments composed of regenerated cellulose or other materials, natural and artificial fibers, or, for example, fused plastic filaments.

[0016] Cellulose materials (pulp) are constructed by a cellulose fiber matrix. The fibers that form such a matrix are fibril bundles, which are composed of microfibrils. Through the fibrillation process, the cellulose fibers are separated into a three-dimensional network of microfibrils with a larger surface area. These entangled fibrils are called microfibrillated cellulose (MFC). The width of the entangled fibrils in MFC can be 50 nm to 2 μm, and the length or longitudinal dimension can be 100 nanometers to 500 micrometers, for example, 100 nanometers to 200 micrometers.

[0017] The method for producing MFC is not limited. MFC can be produced from cellulose fibers using methods known in the art, for example, through high pressure, high temperature, and high-speed impact homogenization. The homogenization process is used to exfoliate or disrupt the cell walls of the fibers and release their substructure, fibrils and microfibrils. Enzymatic and / or mechanical pretreatment of wood fibers can also be used.

[0018] In this disclosure, the expressions "non-regenerated cellulose" or "native cellulose" refer to cellulose or cellulose fibrils or fibers that have not undergone chemical or physical modification of their macromolecular structure. Non-regenerated MFC as discussed herein is substantially non-regenerated and is primarily composed of the crystalline structure of cellulose I. Cellulose I has the structure I α and I β For example, man-made cellulose fibers commonly used in the pulp and paper industry are regenerated and have a crystalline structure other than primarily cellulose I. The conversion of cellulose I to cellulose II (or other forms such as cellulose III or cellulose IV) is irreversible; therefore, these forms are stable and cannot be converted back to cellulose I.

[0019] The cellulose used in the present invention can be derived from any plant-based material. Plant-based raw materials can be woody or non-woody. Woody materials can be based on conifers such as spruce, pine, fir, larch, Douglas fir, or hemlock, or hardwoods such as birch, aspen, poplar, alder, eucalyptus, or acacia, or any mixture of the above. Non-woody materials can be cotton, hemp, flax, sisal, jute, kenaf, bamboo, peat, or coconut. Non-woody natural cellulose fibers can be derived from agricultural residues, grasses, or other plant materials such as straw, leaves, bark, seeds, shells, flowers, vegetables, or fruits. Woody plants have good availability, a small environmental impact, and good fiber quality. The above applies to both unregenerated cellulose and also to regenerated and processed forms of cellulose.

[0020] The present disclosure provides a nonwoven fabric, comprising: (a) Fibrous monofilaments that account for 20 to 100% by weight of the total weight of the nonwoven fabric, i. 80 to 98% by weight of non-regenerated microfibrillated cellulose (MFC) based on the weight of component (a); ii. A fibrous monofilament comprising 2 to 20% by weight of dispersant(s) based on the weight of component (a), selected from carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), methyl ethyl hydroxyethyl cellulose (MEHEC), hydroxypropyl cellulose (HPC), ethyl cellulose (EC), and starch, or any mixture thereof; (b) a nonwoven fabric comprising 0 to 80% by weight of thermoplastic fibers, artificial cellulose fibers, non-wood-derived cellulose fibers, or any mixture thereof based on the total weight of the nonwoven fabric.

[0021] A proportion of the fibrous monofilaments are biodegradable. Such filaments may have good absorption properties and may also be good at insulating.

[0022] The fibrous monofilaments may further comprise additives selected from strength additives, hydrophobic adhesives, pigment(s), and / or other modifier(s), which may be used to tailor the properties of the produced nonwoven fabric, as will be understood by those skilled in the art.

[0023] The dispersant may be a cellulose derivative such as carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), methyl ethyl hydroxyethyl cellulose (MEHEC), hydroxypropyl cellulose (HPC), ethyl cellulose (EC), and starch, or any mixture thereof. In one embodiment, the dispersant is carboxymethyl cellulose (CMC), optionally with an additional dispersant. Anionic polyacrylamide (aPAM) may also be used as a dispersant, either alone or in combination with another dispersant.

[0024] Dispersants have an effect on the shear strength of the fibrous monofilament. Dispersants can be used in an amount of 0.5 to 20 wt. % of the total weight of the dry fibrous monofilament. In one embodiment, the dispersant is used in an amount of 5 to 20 wt. %, or 2 to 16 wt. %, or about 13 to 16 wt. %, e.g., about 14 wt. % of the total weight of the fibrous monofilament.

[0025] For example, CMC may be used in an amount of 0.5 to 20% by weight of the total weight of the dry fibrous monofilament. In one embodiment, CMC is used in an amount of 5 to 20% by weight or about 10% by weight of the total weight of the material fibrous monofilament. In one embodiment, CMC is used in an amount of 4 to 5% by weight of the total weight of the material fibrous monofilament. In one embodiment, CMC is used in an amount of 14 to 16% by weight of the total weight of the fibrous monofilament.

[0026] The strength additives may be dry strength agents such as polyacrylamide resins (amphoteric / anionic / cationic), starch, vegetable gums, carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), and latex, or may be wet strength agents such as cationic glyoxylated resins, polyamidoamine-epichlorohydrin resins (PAE), polyamine-epichlorohydrin resins, urea formaldehyde (UFH), epoxide resins, glyoxylated polyacrylamide (G-PAM), polyethylene oxide (PEO), and one or more suitable crosslinkers such as polyurethanes (PU) or durable water repellents (DWR) known in the art.

[0027] Some chemicals have an effect on, for example, dispersion and strength properties. If desired, for example, two different qualities of CMC can be used.

[0028] At its simplest, the nonwoven fabric may comprise only MFC and CMC, thereby being completely and readily biodegradable.

[0029] The strength agent may be G-Pam. The amount of G-Pam may be 0.5 to 3 wt. % of the total weight of the fibrous monofilament, for example, 2 wt. % of the total weight of the dry fibrous monofilament. The use of G-Pam allows for temporary to permanent wet strength modification.

[0030] The strength agent may be anionic polyacrylamide (aPAM). The amount of aPAM may be 0.5-5% by weight of the total weight of the dry fibrous monofilament, for example, 2-4% by weight of the dry weight of the fibrous monofilament. The higher the amount of aPAM, the better the elasticity of the nonwoven fabric. aPAM is a super-flocculant that can also be used as an additional dispersant. It improves the alignment of fibers in suspension during extrusion onto a solid surface through a small nozzle. aPAM also has an effect on suspension rheology.

[0031] The strength additive can be PEO in an amount of 0.5-5 wt. % of the total weight of the dry fibrous monofilament, e.g., 1-3 wt. % of the fibrous monofilament. PEO enhances the elasticity of the monofilaments and fabrics described herein. PEO also has an effect on suspension rheology.

[0032] To obtain the desired filament properties, strength additives, particularly wet strength additives, must be cured (activated) by heat treatment. Curing conditions can be optimized based on the additive and the desired properties of the final product (filament, yarn, fabric). For example, when PAE is used as a wet strength agent in the monofilaments of the fabrics described herein, wet strength and elongation after curing are improved.

[0033] Tenacity is the conventional measure of the strength of a fiber or yarn. It is usually defined as the ultimate (breaking) force (in grams-force) of the fiber / yarn divided by its linear density. Tenacity is often expressed in cN / (d)tex. Linear density is a value that expresses the weight of the fiber / yarn in grams per 1000 meters of fiber / yarn (tex) or grams per 10,000 meters of fiber / yarn (dtex).

[0034] The hydrophobic adhesive can be alkyl ketene dimer (AKD, alkaline or neutral size), alkenyl succinic anhydride (ASA, size), rosin (acid size), natural wax, and modified sunflower oil adhesive (MSOHO), or any mixture thereof.

[0035] The hydrophobic adhesive may be AKD. The amount may be 0.5 to 10 wt. % of the total weight of the dry fibrous monofilament, for example, 2 to 5 wt. % of the total weight of the dry fibrous monofilament. As a hydrophobic adhesive, AKD reduces the absorbency properties of the monofilament or nonwoven fabric described herein. AKD can also increase the strength of the monofilament or nonwoven fabric described herein.

[0036] The fibrous monofilament may contain 0.0 to 18 wt. %, 0.05 to 15 wt. %, preferably 0.1 to 10 wt. % of additive(s).

[0037] In one embodiment, the nonwoven fabric comprises: (a) Fibrous monofilaments that account for 20 to 100% by weight of the total weight of the nonwoven fabric, i. 80 to 98% by weight of non-regenerated microfibrillated cellulose (MFC) based on the weight of component (a); ii. 2 to 20% by weight of dispersant(s) based on the weight of component (a); iii. 0 to 18 wt. % of other additives; and (b) 0 to 80% by weight of the total weight of the nonwoven fabric of thermoplastic fibers, artificial cellulose fibers, non-wood-derived cellulose fibers, or any mixture thereof.

[0038] The man-made cellulose fiber(s) may be selected from lyocell, viscose, modal, acetate, rayon, and recycled textile waste fibers, or any mixture thereof. In one embodiment, the man-made fiber is lyocell. Thin and long man-made cellulose fibers may improve the strength of the fabric (e.g., measured as elasticity, strength, durability, burst strength, etc.). In addition to the above-mentioned agents, for example, pigments and softeners may be used.

[0039] The thermoplastic fibers can be selected from polypropylene, polyamide, polyester, polypropylene / polyester, and bicomponent short-cut fibers. Thermoplastic fibers can improve the durability of the fabric and provide elongation and electrostatic properties. Electrostatic properties are particularly important in various gas filters, including face masks. In addition, thermoplastic fibers are suitable for thermal bonding of fibers and monofilaments in nonwoven fabrics.

[0040] The non-wood-derived cellulose fibers may be selected from cotton, hemp, flax, sisal, jute, kenaf, bamboo, peat, and coconut, or mixtures thereof, in particular cotton, flax, and hemp, or mixtures thereof. Non-wood cellulose fibers may improve the durability of the fabric. In addition, non-wood cellulose fibers may be used to adjust the absorbency properties.

[0041] Wool or silk can also be used in nonwoven fabrics, with wool being particularly useful where insulating properties are required.

[0042] The nonwoven fabric may comprise 80-98% by weight of non-regenerated MFC and 2-20% by weight of dispersant(s), based on the weight of the fabric. Such nonwoven fabrics are readily dispersible in aqueous solutions and readily biodegradable in most natural environments.

[0043] In one embodiment, the nonwoven fabric has a weight calculated from the weight of the dry monofilament. i. 80 to 98% by weight of non-regenerated microfibrillated cellulose (MFC); ii. 2-20 wt. % of a dispersant(s); iii. Made of monofilaments composed of 0 to 18 wt. % of other additives.

[0044] The nonwoven fabric may be a nonwoven sheet, such as a disposable wipe. The nonwoven fabric may comprise or consist of non-regenerated (cellulose type I crystal form) fibers in the form of MCF and dispersant(s). Optionally, the nonwoven fabric further comprises strength additives, hydrophobic adhesives, pigment(s), and / or other modifier(s). Such nonwoven fabrics and monofilaments described herein are biodegradable and compostable in moist or aqueous natural environments, as shown in the experimental section. Tests have shown that the biodegradability of the monofilaments and fabrics described herein is at the same level as cellulose.

[0045] The following properties are suitable for disposable wipes: 30-90 g / m 2Square mass (DIN EN 29073-1:1992-08) varying from 0.50 to 100 μm, thickness (DIN EN ISO 9073-2:1997-02) varying from 0.50 to 100 μm, air permeability 2100 to 850 l / m 2 / s (DIN EN ISO 9237:1995-12) can be given as an example of a nonwoven fabric as described herein.

[0046] The tear strength (dry) using the trapezoid method (DIN EN ISO 9073-4:2021-05) can vary from 5 to 35 N, e.g., 22.5 N (machine direction) and / or from 40 to 70 N, e.g., 58.8 (cross direction). The respective wet values ​​can be approximately 17.7 N to 50.3 N + / - 5 N. The bursting strength (DIN EN ISO 13938-2:2020-03) can vary from 5 to 65 kPa. The elongations can be 50 and 28%, respectively.

[0047] The present disclosure also discloses articles of manufacture comprising the nonwoven fabric described herein and, optionally, one or more protective layers, and / or a support framework, and / or absorbed moisture or chemicals, and / or a means for immobilizing the nonwoven fabric.

[0048] The product can be a surgical mask, a filter layer, or a protective curtain comprising at least one layer of the nonwoven fabric described herein and at least one protective layer.

[0049] In products for air or gas filtration, the nonwoven fabric as a layer or sheet may contain, for example, 5 to 50% by weight, e.g., about 20% by weight, of thermoplastic fibers based on the total weight of the nonwoven fabric. Thermoplastic fibers provide electrostatic properties for attracting airborne particles. In addition, they enhance durability and, as such, are suitable for thermal bonding of the fabric.

[0050] The protective layer may be used to protect the nonwoven filtration layer from external abrasion, but may also be used to provide a comfort layer between the user's skin and the active nonwoven filtration layer.

[0051] In gas or air filtration, layers such as the nonwoven fabrics described herein are often thin and flexible and therefore may need to be supported in such applications. Air purification and filtration systems may include several protective, pre-filter, and / or filter layers. Typically, the layers of an air purification and filtration system are assembled in association with a support structure, which may, for example, form a channel for gas flow. In face masks, for example, the protective layer may also support the nonwoven fabric filter layer and allow for the attachment of suitable fastening means. In addition to filtration, electrostatic and anti-pathogenic properties may also be incorporated as separate active layers, or the active properties may be included in the nonwoven fabric layers described herein.

[0052] The product may be an impregnated sheet of the nonwoven fabric described herein. The sheet may be a limited-use wipe or a disposable wipe. It may optionally be impregnated with additional solutions or aqueous liquids, optionally including, for example, purification agent(s), fragrance, deodorant, moisturizer, disinfectant, or alcohol solution (ethanol, isopropanol, etc.), containing an oily liquid. Fields of use include, for example, personal hygiene, disinfection, sanitation, surface cleaning, etc. The impregnated sheet may be individually packaged.

[0053] The present disclosure also relates to a method for producing the fibrous, non-regenerated microfibrillated cellulosic monofilaments described herein for producing nonwoven fabrics. The monofilaments may be used in other applications. The method includes forming an aqueous suspension containing 80-98 wt. % water (based on suspension weight) and 2-20 wt. % dry matter, the dry matter including MFC and at least one dispersing agent; extruding the suspension into monofilaments; and drying the monofilaments.

[0054] The present disclosure also relates to fibrous, non-regenerated microfibrillated cellulose-based monofilaments. The monofilaments may comprise or consist of non-regenerated microfibrillated cellulose (MFC) and dispersant(s). The properties may be modified as described above in connection with nonwoven fabrics.

[0055] As used herein, the term "fibrous monofilament" refers to a continuous length of individual fibrils grouped and extending generally along the longitudinal dimension of a cellulose monofilament. The fibers can be intertwined with one another to form a permanent monofilament structure. Monofilaments cannot be opened or broken apart. The fibers grouped together cannot be separated into substructures, such as fiber ribbons or strips, for example, via mechanical cutting, grinding, or chemical separation means. Disintegration of a fibrous monofilament results in only individual fibrils. A fibrous monofilament can comprise a continuous length of several meters or kilometers. The term "monofilament" refers to a single-strand filament produced by extruding a polymer suspension. A fibrous monofilament can also be referred to as a monofilament fiber.

[0056] The fibrous monofilaments described herein may have a tenacity of at least 1 cN / dTex, or at least 1.5 cN / dTex, or 2 cN / dTex, when measured according to the ASTM 3822 / D3822M-14 standard.

[0057] In the longitudinal direction, the monofilaments described herein may have a thickness of about 5-30 μm and a width of about 30-300 μm (the cross section may be flattened). The high cross-sectional aspect ratio of the monofilaments affects the flexibility of the monofilaments. The cross-sectional aspect ratio may be 30-300 μm: 2-30 μm, 30-200 μm: 1-6 μm, or 30-120 μm: 5-10 μm. The monofilaments described herein comprise "non-regenerated cellulose." Note that the desired properties depend on the field of use.

[0058] In pulp and papermaking, the usual order of adding ingredients (added to an aqueous solution) to form an aqueous suspension is MFC, strength agent (e.g., PAE), dispersant (e.g., CMC), and in subsequent stage(s), possible hydrophobic agent and further strength agent. Possible crosslinking agents should be added as early as possible to allow the crosslinking reaction to proceed.

[0059] When producing the monofilaments described herein, the above order can be used. First, MFC and then the dispersant can be added to the aqueous suspension, followed by the strength agent, optional hydrophobic adhesive, and possible further additives, such as further strength agents, depending on the application. One exemplary recipe with a suitable addition order is MFC + CMC + PAE + AKD + ​​aPAM. Note that certain crosslinker activity may require contact with the fiber already in the initial state. Alternatively, CMC (or other dispersant) can be added before MFC.

[0060] Those skilled in the art can use their general knowledge and materials provided by chemical manufacturers to determine suitable pH parameters for activity of strength agents and adhesives.

[0061] It should be noted that in the simplest embodiment, it is possible to produce fibrous monofilaments and / or nonwovens that comprise or consist solely of dispersing agents such as MFC and CMC, in which case the amount of CMC is at least 4% by weight of the total dry weight of the sheet, preferably at least 8%, 10%, 12% or even 14%.

[0062] The fibrous monofilaments described herein are made in an aqueous suspension that includes water, non-regenerated cellulose fibers, and at least one dispersing agent, typically a cellulose derivative.

[0063] Fibrous monofilament: 800-1700kg / m 3 , e.g., 1500 kg / m3 The fibrous monofilaments may have a linear mass density of 3 to 100 grams per 1000 meters, which is 2 to 10 dtex, or preferably a linear mass density of 3 to 10 dtex. The fibrous monofilaments may have a tenacity of 0.5 to 3.0 cN / dtex, as measured according to ASTM 3822 / D3822M-14.

[0064] It is also possible to include other wood-based pulp fibers, or other short natural cellulose fibers such as cotton or flax, or other short man-made cellulose fibers, such as regenerated cellulose fibers such as viscose, cupro, or lyocell. When present in a monofilament containing non-regenerated MFC, the additional fibers considered must be refined to substantially the same size as the MFC.

[0065] In the production of fibrous monofilaments, an aqueous suspension is directed (extruded) through a small nozzle, where the fibers are well aligned (oriented) with the flow. The nozzle delivers the aqueous suspension to a solid surface, which is subsequently dried to obtain fibrous monofilaments. The fibrous monofilaments thus produced are continuous, but can be post-processed into shorter lengths by any suitable method known in the art. Chemical post-processing, such as dyeing, is also possible. The thickness of the fibrous monofilaments can be influenced, at least in part, by adapting the production speed, aqueous suspension concentration, and nozzle geometry. Short cellulose fibril filaments and structures tend to disintegrate in water. This characteristic also enhances their biodegradability.

[0066] The properties of fibrous monofilaments and nonwoven fabrics can be tailored. For example, thickness and strength characteristics can be adapted to the application and use. Also, properties such as absorbency, softness, flexibility, sustainability, wear durability, shape stability, elasticity / inelasticity, and / or combinability with other materials or yarns can have an impact on the usability of fibrous monofilaments. Methods and chemicals known in the textile industry can be used. Waxes can be used to modify the softness and absorbency of the filaments and / or fabrics. AKD, as a hydrophobic agent, reduces absorbency, increases strength and elasticity, and reduces fabric softness when used in large quantities.

[0067] The present disclosure provides a method for producing a nonwoven fabric, comprising: (a) A fibrous monofilament, i. 80 to 98% by weight of non-regenerated MFC based on the weight of component (a); ii. 2 to 20% by weight of dispersant(s) based on the weight of component (a); iii. 0-18 wt. % of other additives; (b) optionally providing additional fibers selected from thermal bonding polymers, man-made cellulose fibers, non-wood cellulose fibers, and any mixtures thereof; (c) depositing the fibrous monofilaments of (a) and the optional fibers of (b) in a random pattern on a surface to form a nonwoven fabric, and optionally drying the formed nonwoven fabric.

[0068] Step (c) may include carding, wet or dry laying, or spunlaying the deposited filaments of (a) and optional fibers of (b) to form a nonwoven fabric.

[0069] Step (c) may include needling, hydroentangling, thermal bonding, or chemical bonding the formed nonwoven fabric.

[0070] Step (c) may be followed by further steps such as impregnating, smoothing, heat setting, drying or calibrating the formed nonwoven.

[0071] In one embodiment, the nonwoven fabric or fibrous monofilament comprises only dispersing agents such as MFC and CMC, in which case the amount of CMC is at least 4%, preferably at least 8%, 10%, 12%, or even 14% by weight of the total dry weight of the fabric or fibrous monofilament.

[0072] It should be understood that the embodiments provided in the above description are for illustrative purposes only, and that various changes and modifications are possible within the scope of the present disclosure. It should also be understood that the terminology used herein is for descriptive purposes and should not be regarded as limiting. Features described herein as separate embodiments may also be provided in combination in a single embodiment. Moreover, various features described herein in the context of a single embodiment may also be provided separately or in any suitable subcombination.

[0073] The present invention is illustrated below by means of examples, which are given for illustrative purposes only and do not limit the scope of the invention. [Example]

[0074] Example 1. Properties of fibrous monofilaments using various recipes Monofilaments were formed as described in WO2018 / 115577A1, and the compositions of the monofilament samples are given in Table 1 below. Table 1. Composition of test samples [Table 1]

[0075] The samples were evaluated for processability, % elongation, strength (cN / dTex), filament width (μ), and gel strength (Pa).

[0076] Measurements were performed according to standard ASTM 3822 / D3822M-14 at RH 65% (+ / - 2%) and temperature 20°C (+ / - 2°C). The same standard was used in the following experiments unless otherwise stated.

[0077] result The results are shown in Figures 1a-1e and Table 2 below. Table 2. Mean results, study 1 represents the reference [Table 2]

[0078] conclusion At its simplest, it has been shown that it is possible to produce sufficient quantities of monofilament using only MFC and dispersant: Monofilaments containing only 4 wt% could be formed (spun) into monofilaments, while 14 wt% provided good strength, elongation, and processability (Sample 4).

[0079] Sample 7 demonstrates that even at 4 wt% CMC, the strength level of the reference sample is achieved when PEO and a-Pam are added, demonstrating that PEO alone (Sample 9) is not sufficient to provide strength.

[0080] Comparing Sample 3 and Sample 4, it can be seen that the CMC without a-Pam provides good rheology (gel strength), i.e., has sufficient dispersion properties.

[0081] Comparing Samples 8 and 10, it can be seen that AKD slightly reduces strength, however AKD is a hydrophobic adhesive that plays a role in controlling water absorption.

[0082] In the compositions tested, PAE was required to obtain good wet strength, and only 2 wt. % results are shown. PEO was not significant in the properties tested here.

[0083] Example 2: Effect of HEC on monofilaments In this experiment, HEC was added to a monofilament recipe and shown to increase the elasticity of the monofilament. Table 3 below summarizes the recipes tested and the properties measured. Fibrous monofilaments were prepared as described in WO2018 / 115577. Table 3 [Table 3-1] [Table 3-2]

[0084] For example, HEC has been shown to increase the elasticity of monofilaments.

[0085] Example 3A: Nonwoven Fabric Properties The suspension and monofilaments were formed as described in WO 2018 / 115577 A1. The monofilaments used contained 82.1 wt.% MFC, 14 wt.% CMC, 1.4 wt.% A-PAM, 2 wt.% PAE, and 0.5 wt.% AKD. Percentages are based on the dry weight of the fibrous monofilament or nonwoven fabric formed from the filament. The aqueous suspension used for the monofilaments had a consistency of approximately 5 wt.%.

[0086] Needle-punched nonwoven fabrics were prepared using conventional methods in parallel samples. These tests were carried out by the Saxon Textile Research Institute eV (STFI). The nonwoven fabrics were tested for mass per unit area, thickness, air permeability, tensile strength, tear strength, and burst strength.

[0087] sample Nonwoven test series a contained 70% or 80% by weight of fibrous monofilaments described herein and 30% or 20% by weight of lyocell, respectively.

[0088] The filaments and lyocell were prepared into nonwoven fabrics using conventional methods, either by carding and needle punching (Samples 1 and 2) or by the aqua-jet method (Sample 3).

[0089] The test program was as follows: Conditioning and test atmosphere: ((20.0±2.0)℃ / (65.0±4.0))% humidity as shown in Table 4 below Table 4 [Table 4-1] [Table 4-2] Table 5. Results [Table 5-1] [Table 5-2] [Table 6-1] [Table 6-2] [Table 7]

[0090] Example 3B: Nonwoven Fabric Properties The suspension and monofilaments were formed as described in WO 2018 / 115577 A1. The monofilaments used contained 82.1 wt.% MFC, 14 wt.% CMC, 1.4 wt.% A-PAM, 2 wt.% PAE, and 0.5 wt.% AKD. Percentages are based on the dry weight of the fibrous monofilament or nonwoven fabric formed from the filament. The aqueous suspension used for the monofilaments had a consistency of approximately 5 wt.%.

[0091] Sample 01 is 70% fibrous monofilament, 30% lyocell, averaging 80 gsm. Sample 02 is 50% fibrous monofilament, 50% lyocell, averaging 80 gsm. Sample 03 is 70% fibrous monofilament, 30% lyocell, averaging 45 gsm. Sample 04 is 50% fibrous monofilament, 50% lyocell, averaging 45 gsm. The samples were carded, hydroentangled, and spunlaced (also referred to as aquajet or hydroentangled).

[0092] method (1) Mass per unit area: DIN EN 29073-1:1992-08 (2) Thickness: DIN EN ISO 9073-2:1997-02, Area: 25cm 2 , Pressure: 5cN / cm 2 (3) Air permeability: DIN EN ISO 9237:1995-12, area: 20cm 2 , Pressure: 200Pa (4) Tensile test, nonwoven fabric: DIN EN 29073-3: 1992-08, gauge length: 200 mm, test speed: 100 mm / min (5) Tear strength, trapezoid method: DIN EN ISO 9073-4:2021-05 (6) Burst characteristics, air pressure method: DIN EN ISO 13938-2:2020-03, equipment: James H. Heal TruBurst Model 610, test area: 50 cm2 , Sample condition: adjusted (7) Flooding velocity (method by determining the rising height): DIN 53924:2020-09 Table 6. Results [Table 8-1] [Table 8-2] [Table 9-1] [Table 9-2] [Table 10] [Table 11-1] [Table 11-2] [Table 12-1] [Table 12-2] [Table 13-1] [Table 13-2] [Table 13-3]

[0093] Conclusion: The nonwoven fabrics made by needle-punched technology have been shown to have better thermal properties (insulation) than the respective fabrics made by aqua-jet technology. The needle-punched fabrics are also thicker.

[0094] The air permeability of 70 wt. % fibrous monofilament and 30 wt. % lyocell described herein was better than that of 80 wt. % fibrous monofilament and 20 wt. % lyocell described herein.

[0095] Thus, both the monofilament and possible other components of the fabric, and the technology used to manufacture the fabric, have an effect on the properties of the fabric. This provides numerous ways to tailor nonwoven fabrics for various applications.

[0096] Example 4: PAE Curing Monofilaments were prepared as described in WO2018 / 115577. The composition of the fibrous monofilaments was 84.6 wt% MCF, 12 wt% CMC, 2 wt% PAE, and 1.4 wt% aPam.

[0097] Heat treatment / curing of the filaments was carried out by holding the fibers at 120° C. for 10 minutes and at 80° C. for 12 or 24 hours. 120° C. was the laboratory oven condition, while 80° C. was used to evaluate the large scale process (heating room). Table 7 [Table 14]

[0098] The results, shown in Table 7 above, indicate that the uncured samples did not have sufficient wet strength over time, although there was a slight increase. A 10-minute laboratory-scale 120°C cure was used as a reference. At the laboratory scale, each monofilament was subjected to uniform cure. The 80°C experiment was a larger-scale experiment that could be performed. It was shown that a 12-hour cure time was sufficient to ensure approximately laboratory-scale cure, and that longer times at the same temperature did not improve strength.

[0099] Example 5: Biodegradability in an aqueous environment The monofilaments used in this experiment and in the preparation of the nonwoven fabrics were formed as described in WO 2018 / 115577. The composition of the fibrous monofilaments was 84.6 wt% MCF, 12 wt% CMC, 2 wt% PAE, and 1.4 wt% aPam.

[0100] The biodegradation of the monofilament material (recipe above) was evaluated in an aqueous anaerobic biodegradation test. The test medium was anaerobically digested sludge obtained from a sewage treatment plant that primarily processes domestic waste. A set of 12 equal test vessels, each with a total volume of 120 ml, was used. Each test vessel was filled with 90 g of test medium and (except for the control and DIC reactors) with 23 mg of the reference item (microcrystalline cellulose powder) or the test item (fines, added as received). The reactors were maintained at 35°C ± 2°C in a water bath. The DIC reactor was used to correct for the inorganic carbon dissolved in the test medium at the start of the test. The test was performed three times, with a total test period of 60 days.

[0101] Biodegradability tests were carried out by OWS nv, Belgium, according to standard ISO 11734, Evaluation of the “ultimate” anaerobic biodegradability of organic compounds in digested sludge - Method by measurement of the biogas production (1995).

[0102] A known volume of anaerobic sludge suspended in oxygen-free medium (equivalent to approximately 10% of the sludge concentration in the actual digester) is placed in a suitable container, leaving a headspace through which any gases produced can be released. Prior to sealing, a small amount of the test compound is added.

[0103] The vessels are incubated at a constant temperature. The headspace pressure resulting from gas production is measured to determine the DIC (dissolved inorganic carbon, which is inorganic carbon (mainly CO2) dissolved in the liquid phase) content of the digestate. From the measured net gas products and the net DIC formation, the extent of biodegradation is calculated. The kinetics of biodegradation can be established by taking measurements at suitable intervals during the course of the test.

[0104] The sludge used was obtained from a sewage treatment plant in Gent (Belgium), which treats domestic wastewater. Before use, the inoculum was left for 6 days to stabilize. This post-fermentation was necessary to reduce the biogas production rate (background activity). After post-fermentation, the sludge was centrifuged at approximately 2500 g for 5 minutes in fully filled, sealed centrifuge tubes at room temperature. The supernatant was discarded, and the sludge pellet was suspended in anoxic mineral salts medium. This centrifugation-wash step was repeated twice. The inoculum was diluted with mineral salts medium until a final concentration of 2.5 g TS / L was obtained, falling within the desired range of 1-3 g / L. The organic matter content of the test medium on TS was 39.9%. A summary of the diluted sludge characteristics is given in Table 8. The pH was adjusted to 7.0 ± 0.2 with dilute mineral acid. Table 8. Inoculum characteristics [Table 15]

[0105] The reference and test items were analyzed for total solids (TS), volatile solids (VS), and total organic carbon content (TOC). The results are given in Table 9. Table 9. Total Solids (TS), Volatile Solids (VS), and Total Organic Carbon (TOC) Contents of Reference and Test Items [Table 16]

[0106] Gas Results The pressure increase and biogas composition of the negative control, cellulose control, and test materials were evaluated, indicating that the monofilament material behaved like cellulose, with a short delay in some reactions (data not shown). Table 10 shows the biogas composition after 60 days of testing. Gas composition was within normal ranges for all test vessels. The high CH content demonstrates that a significant amount of CO was still dissolved in the liquid phase. Table 10. Average biogas composition (%) after 60 days of testing [Table 17]

[0107] Biodegradation results Table 11 shows the percentage biodegradation of the reference and test items after 60 days, calculated as the amount of organic carbon in the sample that was converted to gaseous carbon (CH4 and CO2, both present in the headspace and dissolved in the liquid (DIC)). Table 11. Percentage biodegradation at the end of the test (60 days) [Table 18]

[0108] The values ​​in Table 11 do not include the amount of carbon originally present in the test or reference item that is converted to biomass carbon during digestion. Some of the carbon that is biodegraded is actually used to build new bacterial biomass. For anaerobic digestion, the biomass yield factor is 10% to 30%. This means that for every gram of carbon consumed, 10% to 30% is used for new bacterial biomass, while 70% to 90% is converted to gaseous, inorganic carbon in the form of CH4 or CO2.

[0109] The biodegradation result of the reference item cellulose obtained after 60 days of testing was 71.9% ± 10.8%, which means that the criteria for a valid test (ISO 11734 (1995): 60% degradation of the reference item) were met.

[0110] The tested monofilament materials began to degrade after a lag period of approximately 7 days. After approximately 35 days, a plateau phase was obtained for all replicates. The test materials reached 78.0% ± 3.8% biodegradation (or 108.4% relative to cellulose) after 60 days. In general, test items demonstrated a satisfactory level of biodegradation when 90% absolute or relative biodegradation was reached. This means that the monofilament materials can be considered biodegradable under aqueous, neutral, anaerobic conditions within 60 days.

[0111] conclusion The tests show that the monofilament material began to degrade after a lag period of approximately 7 days. After approximately 35 days, a plateau phase was obtained for all replicates. The test article reached 78.0% ± 3.8% biodegradation (or 108.4% for cellulose) after 60 days. The monofilament material can be considered biodegradable under aqueous, neutral, anaerobic conditions within 60 days.

[0112] Example 6: Industrial Composting The aerobic biodegradation of the test item monofilament material was evaluated by biodegradation tests conducted in controlled composting trials at an incubation temperature of 58°C ± 2°C by OWS nv, Belgium. Tests were performed in duplicate. The reference material cellulose was added as a powder and the test item monofilament material was pre-size reduced (cryogenically ground to less than 1 mm). At the start, 80 g of the reference or test item was added to 1200 g of compost inoculum. The control reactor contained only 1200 g of inoculum. The total test duration was 45 days.

[0113] The following standard was ISO 14855-1 Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions - Method by analysis of evolved carbon dioxide (2012), but twice instead of three times.

[0114] The inoculum was derived from the organic fraction of municipal solid waste. The waste was stabilized and aerated under controlled conditions in a laboratory compost bin for over 20 weeks. Prior to use, the compost was passed through a 5 mm sieve. The characteristics of the starting inoculum are given in Table 12.

[0115] The inoculum should have a total solids (TS) content of 50% to 55% and a volatile solids content (VS) on TS of greater than 30%. Additionally, the pH should be between 7.0 and 9.0. As can be seen from Table 12, these requirements were met. The inoculum exhibited a total solids content of 54.1%, a volatile solids content on TS of 33.4%, and a pH of 7.5.

[0116] According to standard ISO 14855-1 (2012), CO production of 50 mg to 150 mg CO / g VS should be measured for the control during the first 10 days of the test. After 10 days, an optimal background activity of 57 mg CO / g VS was measured. Table 12. Inoculum characteristics [Table 19]

[0117] The total solids (TS), volatile solids (VS), total organic carbon content (TOC), and theoretical carbon dioxide evolution (ThCO2) of the reference and test items are summarized in Table 13. Table 13. TS, VS, TOC, and ThCO2 of reference and test items [Table 20]

[0118] Biodegradation results Table 14 shows the net CO2 production and percentage biodegradation of the reference and test items at the end of the study (45 days). Table 14. Net CO2 production and biodegradation after 45 days [Table 21]

[0119] Biodegradation of the reference item cellulose began almost immediately and proceeded at a good rate. After 12 days, cellulose was already 71.5% degraded. The rate of biodegradation gradually slowed, and at the end of the test (45 days), the biodegradation plateau reached a level of 91.2% ± 1.5%. A test is considered valid if, after 45 days, the biodegradation percentage of the reference item exceeds 70% and the standard deviation of the biodegradation percentage of the reference item at the end of the test is less than 20%. Both requirements were met.

[0120] Biodegradation of the tested monofilament material also began almost immediately and proceeded at a good rate. After 20 days, the monofilament material of the test item was already 69.6% degraded. The rate of biodegradation gradually slowed, and at the end of the test (45 days), the biodegradation plateau reached a level of 87.0% ± 7.5%. On a relative basis, a biodegradation percentage of 95.3% was calculated compared to the preferred reference substrate, cellulose.

[0121] The monofilament material demonstrated a satisfactory level of biodegradation when it reached 90% absolute or relative biodegradation. The maximum allowable test period determined by industrial composting standards is 180 days. It can be concluded that the tested monofilament material met the 90% requirement within 45 days of testing under the given aerobic conditions.

[0122] Example 7: Properties of nonwoven fabric Fibrous monofilaments were formed as described in WO 2018 / 115577. The composition of the fibrous monofilaments was 84.6 wt% MCF, 12 wt% CMC, 2 wt% PAE, and 1.4 wt% aPam.

[0123] A nonwoven fabric containing 40% by weight of fibrous monofilament, 40% by weight of lyocell, and 20% by weight of PP BiCo (polypropylene bicomponent) was formed by using aquajet technology by Suominen Corporation, Finland. Measurements are performed on dry and wet sheets.

[0124] The water retention value (WRV) characterizes the ability of a fiber to retain water when a defined centrifugal force is applied according to DIN 53814, which removes most of the liquid absorbed between the fibers. The water retention capacity or water absorption value (WIV) measures the amount of liquid absorbed between the fibers under free swelling conditions according to the European Pharmacopoeia. Table 15 [Table 22]

[0125] Tensile strength (machine direction, md and cross direction, cd) was performed on both dry (solid line) and wet (dashed line) sheets, and the results are shown in Figures 2a and 2b (machine direction and cross direction).

[0126] In the nonwoven industry, high absorbency is an important and highly sought-after property in many end uses, such as diapers, tampons, sanitary napkins, medical sponges, baby wipes, wiping cloths, etc. Each of these applications requires high capacity to absorb and retain water and other aqueous fluids, especially bodily fluids.

[0127] The water absorption capacity of the nonwoven fabric has been found to be very good, even up to about 1000% of the dry weight of the nonwoven fabric, a property that is valuable, for example, in diapers and other absorbent applications.

Claims

1. A nonwoven fabric, (a) 20 to 100% by weight of fibrous monofilaments based on the total weight of the nonwoven fabric, i. 80-98% by weight of non-regenerated microfibrillated cellulose (MFC) based on the weight of component (a); ii. A fibrous monofilament comprising 2 to 20% by weight of dispersant(s) based on the weight of component (a), selected from carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), methyl ethyl hydroxyethyl cellulose (MEHEC), hydroxypropyl cellulose (HPC), ethyl cellulose (EC), and starch, or any mixture thereof; (b) 0 to 80% by weight of the total weight of the nonwoven fabric of thermoplastic fibers, artificial cellulose fibers, non-wood-derived cellulose fibers, or any mixture thereof.

2. 10. The nonwoven fabric of claim 1, wherein the fibrous monofilaments further comprise an additive selected from strength additives, hydrophobic adhesives, pigment(s), and / or other modifier(s).

3. 3. The nonwoven fabric of claim 1 or 2, wherein the strength additive is a dry strength agent such as polyacrylamide resins (amphoteric / anionic / cationic), starch, vegetable gum, carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), and latex, or a wet strength agent such as cationic glyoxylated resins, polyamidoamine-epichlorohydrin resins (PAE), polyamine-epichlorohydrin resins, urea formaldehyde (UFH), epoxide resins, and crosslinkers such as polyurethane (PU) or durable water repellents (DWR) known in the art.

4. 4. The nonwoven fabric of claim 2 or 3, wherein the hydrophobic adhesive is selected from alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), rosin, natural wax, and modified sunflower-based adhesive (MSOHO).

5. 5. The nonwoven fabric of claim 2, wherein the strength additive is G-Pam in an amount of 0.5 to 3 wt. % of the total weight of the fibrous monofilaments, for example, 2 wt. % of the total weight of the fibrous monofilaments.

6. 5. The nonwoven fabric of claim 2, wherein the strength agent is anionic polyacrylamide (aPAM) in an amount of 0.5 to 5 wt. % of the total weight of the fibrous monofilaments, for example, 2 to 4 wt. % of the total weight of the fibrous monofilaments.

7. 5. The nonwoven fabric according to claim 2, wherein the strength agent is PEO in an amount of 0.5 to 5 wt. % of the total weight of the fibrous monofilaments.

8. 8. The nonwoven fabric according to claim 2, wherein the hydrophobic adhesive is AKD in an amount of 0.5 to 10 wt. % of the total weight of the fibrous monofilaments, for example, 2 to 5 wt. % of the total weight of the fibrous monofilaments.

9. 10. The nonwoven fabric of any one of the preceding claims, wherein the man-made cellulose fiber(s) is / are selected from the list consisting of lyocell, viscose, modal, acetate, rayon, and recycled textile waste fibers, or any mixture thereof.

10. 10. The nonwoven fabric according to any one of the preceding claims, wherein the thermoplastic fibers are selected from the list consisting of polypropylene, polyamide, polyester, polypropylene / polyester, and bicomponent short cut fibers.

11. 10. The nonwoven fabric of any one of the preceding claims, wherein the non-wood-derived cellulose fibers are selected from the list consisting of cotton, hemp, flax, sisal, jute, kenaf, bamboo, peat, and coconut, or mixtures thereof, for example cotton, flax, hemp, or mixtures thereof.

12. 12. The nonwoven fabric of any one of claims 1 to 11, wherein the fabric comprises 80 to 98 wt% by weight of non-regenerated MFC and 2 to 20 wt% of dispersant(s).

13. 13. A product comprising the nonwoven fabric of any one of claims 1 to 12 and, optionally, one or more protective layers, and / or a supporting framework, and / or absorbed moisture or chemicals, and / or means for immobilizing the nonwoven fabric.

14. 14. The product of claim 13, wherein the product is a surgical mask, a filter layer, or a protective curtain, comprising at least one layer of the nonwoven fabric of any one of claims 1 to 12 and at least one protective layer.

15. 15. Product according to claim 13 or 14, wherein the product is an impregnated sheet of nonwoven fabric according to any one of claims 1 to 12.

16. 1. A method for producing fibrous monofilaments, comprising: forming an aqueous suspension comprising 80-98 wt. % water and 2-20 wt. % dry matter, the dry matter comprising MFC and at least one dispersant selected from carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), methyl ethyl hydroxyethyl cellulose (MEHEC), hydroxypropyl cellulose (HPC), ethyl cellulose (EC), and starch, or any mixture thereof; extruding the suspension into monofilaments; and drying the monofilaments.

17. A fibrous monofilament, based on the dry weight of said monofilament: a. 80-98 wt. % non-regenerated microfibrillated cellulose (MFC); b. 2-20 wt. % of dispersant(s) selected from carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), methyl ethyl hydroxyethyl cellulose (MEHEC), hydroxypropyl cellulose (HPC), ethyl cellulose (EC), and starch, or any mixture thereof; and optionally c. an additive as defined in any one of claims 2 to 7, Fibrous monofilaments having a tenacity of at least 1 cN / dTex measured at RH 65% (+ / - 2%) and a temperature of 20°C (+ / - 2°C) using standard ASTM 3822 / D3822M-14.

18. 1. A method for producing a nonwoven fabric, comprising: (a) a fibrous monofilament, i. 80 to 98 wt. % non-regenerated MFC based on the weight of component (a); ii. Providing a fibrous monofilament comprising 2 to 20% by weight of the weight of component (a) of dispersant(s) selected from carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), ethyl hydroxyethyl cellulose (EHEC), methyl cellulose (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), methyl ethyl hydroxyethyl cellulose (MEHEC), hydroxypropyl cellulose (HPC), ethyl cellulose (EC), and starch, or any mixture thereof; (b) optionally providing additional fibers selected from thermal bonding polymers, man-made cellulose fibers, non-wood cellulose fibers, and any mixtures thereof; (c) depositing the filaments of (a) and the optional fibers of (b) in a random pattern onto a surface to form a nonwoven fabric, and optionally drying the formed nonwoven fabric.

19. 20. The method of claim 18, wherein step (c) comprises carding, wet or dry laying, or spunlaying the deposited filaments of (a) and optional fibers of (b) to form a nonwoven fabric.

20. 20. The method of claim 18 or 18, wherein step (c) comprises needling, hydroentangling, thermal bonding, or chemical bonding the formed fabric.

21. 21. The method of any one of claims 18 to 20, wherein step (c) comprises impregnating, smoothing, heat setting, drying, or calibrating the formed fabric.

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