Plant-based nonwoven fabric

Abstract

Plant-based nonwoven fabrics and methods of making the same are provided. The plant-based nonwoven fabric includes a plurality of regenerated cellulose fibers physically entangled with a plurality of cellulosic pulp fibers. The plant-based nonwoven fabric has a first side and a second side, wherein the first side and / or the second side has a three-dimensional (3D) image formed therein.

Description

[0001] Cross-reference to related applications This application claims priority to U.S. Provisional Application No. 63 / 604,309, filed November 30, 2023, the entire contents of which are expressly incorporated herein by reference. Technical Field

[0002] Embodiments of the present invention generally relate to a plant-based nonwoven fabric comprising multiple regenerated cellulose fibers physically entangled with multiple cellulose pulp fibers, wherein a first side and / or a second side of the nonwoven fabric has a three-dimensional (3D) image formed therein. Background Technology

[0003] The use of natural fiber materials in industrial applications, such as absorbent pads or wipes, has gained increasing attention as an environmentally friendly and proactive method for forming nonwoven fabrics. However, 100% cellulose products often clump or clump when wet and lack resilience. For example, some traditional plant-based nonwoven fabric methods formed from 100% cellulose fibers involve carded spunlace rayon, which has no pattern (flat) or a very shallow mesh pattern. Other methods employ a three-layer fabric formed from carded rayon / air-laid pulp / carded rayon (CPC), which has a flat or mesh pattern. At least in part due to the traditional disadvantages of plant-based nonwoven fabrics (where all fibers are formed from plant-based materials such as cellulose fibers), some wipes have mitigated these disadvantages by incorporating a significant amount of petroleum-based fibers (such as polyolefin spunbond fibers) with cellulose fibers. Summary of the Invention

[0004] One or more embodiments of the present invention can solve one or more of the above-mentioned problems. According to certain embodiments of the present invention, a plant-based nonwoven fabric is provided, comprising multiple regenerated cellulose fibers physically entangled with multiple cellulose pulp fibers. The nonwoven fabric has a first side and a second side, and the first side and / or the second side has a three-dimensional (3D) image formed therein. The 3D image may include multiple recessed portions and multiple raised portions.

[0005] In another aspect, the present invention provides a method for producing plant-based nonwoven fabrics, such as those described and disclosed herein. The method may include the steps of: (i) providing or forming a carded web or carded fabric comprising a plurality of regenerated cellulose fibers; (ii) depositing a plurality of cellulose pulp fibers onto the carded web or carded fabric to form an intermediate nonwoven material; and (iii) mechanically entangled the plurality of regenerated cellulose fibers and the plurality of cellulose pulp fibers together to provide a plant-based nonwoven fabric.

[0006] In another aspect, the present invention provides a wiping cloth comprising a plant-based nonwoven fabric, such as those described and disclosed herein, and a liquid additive disposed on or within a first outer surface and / or a second outer surface of the plant-based nonwoven fabric. Attached Figure Description

[0007] The invention will now be described more fully with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the invention. In fact, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable this disclosure to meet applicable legal requirements. Throughout the text, the same numerals refer to the same elements, and wherein: Figure 1 The thickness measurement of a plant-based nonwoven fabric according to certain embodiments of the present invention is illustrated; Figure 2 This is a flowchart illustrating certain methods for producing plant-based nonwoven fabrics according to certain embodiments of the present invention; Figure 3 The following data show the percentage thickness recovery of plant-based nonwoven fabrics compared to paper wipes according to certain embodiments of the present invention; and Figure 4 The following data, normalized to basis weight, show the percentage of thickness recovery of a plant-based nonwoven fabric compared to a 100% rayon nonwoven wipe according to certain embodiments of the present invention. Detailed Implementation

[0008] The invention will now be described more fully. In fact, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable this disclosure to meet applicable legal requirements. As used in the specification and appended claims, the singular forms “a,” “an,” and “the” include the plural references unless the context clearly specifies otherwise.

[0009] Some embodiments of the present invention may relate to plant-based nonwoven fabrics, such as wet or dry wipes, which are substantially or entirely formed of plant-based fibers. For example, plant-based nonwoven fabrics may contain a total fiber content of 100% plant-based fibers. Plant-based fibers may be hydroentangled (or otherwise mechanically entangled together). Plant-based nonwoven fabrics may, for example, be formed from one or more different types of plant-based fibers (e.g., cellulose fibers). According to some embodiments of the present invention, plant-based nonwoven fabrics may exhibit or have particularly desirable wet resilience, especially for plant-based nonwoven fabrics. Unlike some embodiments of the present invention, conventional 100% cellulose products typically clump together and fail to rebound when wet. Therefore, the wet resilience associated with the plant-based nonwoven fabrics described and disclosed herein provides a significantly beneficial effect, at least for the wipe industry.

[0010] According to certain embodiments of the invention, plant-based nonwoven fabrics can be formed from a carded layer of lyocell fiber and an air-laid pulp layer, both layers having been hydroentangled together. These layers can be hydroentangled at one or more hydroentanglement stations. For example, a first station or a first set of hydroentanglement stations (e.g., on a non-image-forming surface) can hydroentangle the lyocell fiber and the air-laid pulp together to impart sufficient structural integrity such that a second station or a second set of hydroentanglement stations can further hydroentangle the fibers together (i) at a lower average fluid pressure and (ii) on an imaging roller or imaging device to form a substantial three-dimensional (3D) image in the plant-based nonwoven fabric. In this respect, the 3D image is formed and / or defined by the orientation of the corresponding fibers on the first and / or second outer surfaces. For example, the first outer surface having the 3D image may have one or more protrusions at selected locations, while the second outer surface may have one or more corresponding recesses at selected locations. In other words, a location on the first outer surface may have a raised area, while the corresponding location on the back of the plant-based nonwoven fabric has a recessed area. For example, one or more raised areas of the 3D image of the first outer surface may include markings extending outward from the first outer surface, while the back of the plant-based nonwoven fabric will have markings recessed and extending inward toward the first outer surface. That is, a protrusion on the first outer surface may be associated with or correspond to a recessed portion in the second (opposite) outer surface.

[0011] Without being bound by theory, it is believed that 3D imaging, lyocell fibers (e.g., higher wet strength), and the method of incorporating cellulose pulp fibers into the carding layer of regenerated cellulose fibers (e.g., lyocell fibers) collectively contribute to the wet resilience associated with certain embodiments of the present invention. For example, the incorporation of cellulose pulp fibers into the carding layer results in Tabor abrasion comparable to that of more conventionally durable fabrics (compared to typical spunlace nonwovens). For example, it is believed that entanglement of multiple regenerated cellulose fibers (e.g., lyocell fibers) and cellulose pulp fibers at lower fluid pressures during the final hydroentangling operation unexpectedly produces a stronger, more durable nonwoven than the same nonwoven produced at higher fluid pressures during the final hydroentangling operation. This results in, for example, higher tensile strength, lower elongation, and increased Tabor abrasion cycles (e.g., a measure of durability).

[0012] As used herein, the terms "nonwoven fabric" and "nonwoven web" can include webs having a structure of single fibers, fibers, and / or filaments that are interlaced but not arranged in a recognizable repeating pattern as in knitted or woven fabrics. According to certain embodiments of the invention, nonwoven fabrics or webs can be formed by any method conventionally known in the art, such as meltblown, spunbond, needle punching, hydroentangling, air-laid, and bonded carding. As used herein, "nonwoven web" can include multiple single fibers that have not undergone a consolidation process. In some cases, "nonwoven web" can include multiple layers, such as one or more spunbond layers and / or one or more meltblown layers. For example, a "nonwoven web" can include a spunbond-meltblown-spunbond structure.

[0013] As used herein, the terms “fabric” and “nonwoven fabric” can include fiber webs in which multiple fibers are mechanically entangled or interconnected, fused together and / or chemically bonded together. For example, a bonding or consolidation process can be applied to a single-layered nonwoven fiber web to bond at least a portion of the individual fibers together to form a coherent (i.e., bonded) fiber web composed of interconnected fibers.

[0014] As used herein, the term "layer" may include combinations of generally identifiable similar material types and / or functions present in the XY plane.

[0015] As used herein, the terms "bonded" and "bonded" can include bringing at least a portion of the fibers of a nonwoven web closer together or attaching them (e.g., thermally fused together, chemically bonded together, and / or mechanically entangled together) to form one or more bonded sites that, compared to an unbonded web, increase resistance to external forces (e.g., abrasion and tensile forces). For example, one or more bonded sites can include discrete or localized regions of the web material that have been softened or melted and optionally subsequently or simultaneously compressed to create discrete or localized deformations in the web material. Furthermore, the term "bonded" can include the entire nonwoven web being processed such that at least a portion of the fibers are brought closer together or attached (e.g., thermally fused together, chemically bonded together, and / or mechanically entangled together), for example by thermal bonding or mechanical entanglement (e.g., hydroentanglement). Additionally, the terms "bonded" and "bonded" can include bonding performed by a hot-air bonding process. As used herein, the terms "hot-air bonded" and "hot-air bonded" can include nonwoven webs bonded by a bonding process, wherein hot air is used to melt the fibers on the surface of the web and optionally within the web. By way of example only, hot air can be blown across the web in a conveyor-type oven or drawn through the web under vacuum as it passes through a porous roller. The temperature and rate of the hot air are parameters that determine the level or degree of bonding in the nonwoven web. According to certain embodiments of the invention, the temperature of the hot air can be high enough to melt, induce flow, and / or fuse multiple fibers (e.g., amorphous fibers) having a lower melting point or lower initial melting point to multiple fibers (e.g., semi-crystalline or crystalline fibers) having a higher melting point or higher initial melting point. According to certain embodiments of the invention, such a web can be considered a "bonded nonwoven," a "nonwoven fabric," or simply a "fabric."

[0016] As used herein, the term "longitudinal" or "MD" refers to the direction in which the fabric is produced or transported. The term "transverse" or "CD" as used herein refers to the direction in which the fabric is substantially perpendicular to the MD.

[0017] As used herein, the term "cellulose fiber" may include fibers derived from hardwood trees, softwood trees, or a combination of hardwood and softwood trees, prepared by any known suitable cooking, refining, and bleaching operation for use, for example, in papermaking feedstocks and / or fluff pulp feedstocks. Cellulose fibers may include regenerated fibers and / or virgin fibers. Regenerated fibers differ from virgin fibers in that the fibers have undergone at least one drying process. In some embodiments, at least a portion of the cellulose fibers may be derived from non-woody herbaceous plants, including but not limited to kenaf, cotton, hemp, jute, flax, sisal, or Manila hemp. In some embodiments of the invention, cellulose fibers may include bleached or unbleached pulp fibers, such as high-yield pulp and / or mechanical pulp, such as thermomechanical pulp (TMP), chemimechanical pulp (CMP), and bleached chemithermomechanical pulp (BCTMP). In this regard, the term "pulp" as used herein may include cellulose that has been treated (e.g., heat-treated, chemically treated, and / or mechanically treated). According to some embodiments of the invention, cellulose fibers may include one or more regenerated cellulose fibers (e.g., viscose, rayon, lyocell, etc.). According to certain embodiments of the present invention, cellulose fibers may include one or more pulp materials (e.g., cellulose pulp fibers).

[0018] As used herein, the term "fiber" can refer to staple fibers, meltblown fibers, and / or continuous spunbond filaments. In this regard, the term "spunbond fiber" may be used interchangeably with "spunbond filament." Fibers generally refer to elongated particles whose apparent length exceeds their apparent width, and according to certain embodiments of the invention, whose apparent length substantially exceeds their apparent width.

[0019] As used herein, the term "spunbond" can include fibers formed by extruding molten thermoplastic material from a plurality of small (typically circular) capillaries of a spinneret into filaments, followed by a rapid reduction in the diameter of the extruded filaments. According to one embodiment of the invention, spunbond fibers are generally non-sticky when deposited onto a collection surface and can be substantially continuous as disclosed and described herein. It should be noted that the spunbond material used in certain composites of the invention can include the SPINLACE® nonwoven material described in the literature. Spunbond fibers can, for example, include continuous fibers.

[0020] As used herein, the term "continuous fiber" refers to a fiber that has not been cut from its original length before being formed into a nonwoven web or nonwoven fabric. Continuous fibers, such as spunbond fibers, can have an average length greater than about 15 centimeters to more than 1 meter, and can be as long as the web or fabric formed. For example, continuous fibers as used herein can include fibers whose length is at least 1,000 times their average diameter, such as fibers whose length is at least about 5,000, 10,000, 50,000, or 100,000 times their average diameter.

[0021] As used herein, the term "short fiber" can include fibers cut from filaments. According to some embodiments, any type of filament material can be used to form short fibers. For example, the average length of short fibers can include (by way of example only) from about 2 cm to about 15 cm, such as at least about any of the following: 2, 3, 4, 5 and 6 cm, and / or at most about any of the following: 15, 12, 10, 8 and 6 cm.

[0022] As used herein, the term "meltblown" can refer to the process of extruding molten thermoplastic material through multiple fine die capillaries to form molten wires or filaments, which are then fed into a converging high-speed (typically hot) gas stream (e.g., air) that thins the molten thermoplastic filaments to reduce their diameter, down to the diameter of microfibers, according to certain embodiments of the invention. According to one embodiment of the invention, the die capillaries may be circular. The meltblown fibers are then carried by the high-speed gas stream and deposited onto a collection surface to form a randomly distributed meltblown fiber web. The meltblown fibers may include microfibers, which may be continuous or discontinuous, and are typically viscous upon deposition onto the collection surface. However, meltblown fibers are shorter than spunbond fibers.

[0023] According to certain embodiments of the present invention, a plant-based nonwoven fabric is provided, comprising multiple regenerated cellulose fibers, such as short fibers, physically entangled with multiple cellulose pulp fibers. The nonwoven fabric has a first side and a second side, and the first side and / or the second side has a three-dimensional (3D) image formed therein. The 3D image may include multiple recessed portions and multiple raised portions. According to certain embodiments of the present invention, the multiple regenerated cellulose fibers may include viscose fibers, rayon fibers, acetate fibers, triacetate fibers, modal fibers, lyocell fibers, or any combination thereof.

[0024] According to certain embodiments of the invention, the multiple regenerated cellulose fibers may comprise a blend of rayon fibers and lyocell fibers, wherein the lyocell fibers comprise about 30 to about 95% by weight of the blend, for example, at least about any one of the following: 30, 40, and 50% by weight, and / or at most about any one of the following: 95, 90, 85, 80, 75, 70, 65, 60, 55, and 50% by weight. Alternatively, the multiple regenerated cellulose fibers may consist of lyocell fibers (i.e., 100% lyocell fibers).

[0025] According to certain embodiments of the invention, the nonwoven fabric has a total fiber content, and the plurality of regenerated cellulose fibers may account for about 20 to about 80% by weight of the total fiber content, for example, at least about any one of the following: 20, 25, 30, 35, 40 and 45% by weight of the total fiber content, and / or at most about any one of the following: 80, 75, 70, 65, 60, 55, 50 and 45% by weight of the total fiber content. Additionally or alternatively, the nonwoven fabric has a total fiber content, and the plurality of cellulose pulp fibers account for about 20 to about 80% by weight of the total fiber content, for example, at least about any one of the following: 20, 25, 30, 35, 40 and 45% by weight of the total fiber content, and / or at most about any one of the following: 80, 75, 70, 65, 60, 55, 50 and 45% by weight of the total fiber content.

[0026] Optionally, the nonwoven fabric may include multiple polylactic acid (PLA) fibers, such as spunbond PLA fibers, meltblown PLA fibers, or short PLA fibers; wherein the multiple PLA fibers are physically entangled with multiple regenerated cellulose fibers and multiple cellulose pulp fibers. Alternatively, the multiple PLA fibers may be located on a first and / or second side of the nonwoven fabric. For example, the multiple PLA fibers may include meltblown fibers comprising “meltblown shots” and / or “meltblown ropes”, which can provide increased roughness to one or both sides of the nonwoven fabric, for example, to improve the nonwoven fabric’s ability to provide a scrubbing action to remove debris. As used herein, the term “meltblown shot” may include a rough, non-uniform, or discontinuous layer applied in a meltblown process, which is intentionally operated to produce random spheres of polymer (e.g., PLA) interconnected with fiber bundles. Furthermore, the term "meltblown rope" as used herein can also include a rough, non-uniform, or discontinuous layer applied in a meltblown process, which is intentionally operated to produce random "ropes" or bundles of polymer interconnected with fiber bundles. The difference between a meltblown rope and a meltblown projectile is that a meltblown rope can be longer and / or narrower than a meltblown projectile. Both meltblown ropes and / or meltblown projectiles can comprise irregularly shaped fibers, clumps, or particles. In this respect, for example, meltblown ropes and / or meltblown projectiles can comprise fibers, clumps, particles, or spheres having a non-circular cross-section. Meltblown ropes and / or meltblown projectiles can be randomly and irregularly distributed within the bulk of the meltblown layer and / or on the surface of the meltblown layer. For example, meltblown ropes and / or meltblown projectiles can extend along random paths and may intersect and / or cross at random locations. However, meltblown ropes and / or meltblown projectiles may not intersect or cross at all.

[0027] According to certain embodiments of the invention, the nonwoven fabric may have a basis weight of about 20 to about 100 grams per square meter (gsm), for example at least about any of the following: 20, 25, 30, 35, 40, 45 and 50 gsm, and / or at most about any of the following: 100, 95, 90, 85, 80, 75, 70, 65, 60, 55 and 50 gsm.

[0028] According to certain embodiments of the present invention, the nonwoven fabric includes a first side (e.g., a first outermost side) having a first fiber distribution and a second side (e.g., a second outermost side) having a second fiber distribution different from the first fiber distribution. For example, the first fiber distribution includes a first amount of regenerated cellulose fibers greater than a first amount of cellulose pulp fibers, and the second fiber distribution includes a second amount of regenerated cellulose fibers less than a second amount of cellulose pulp fibers. The nonwoven fabric has a thickness in the z-direction perpendicular to both the longitudinal and transverse directions, and includes a midpoint in the z-direction located between the first and second sides, wherein the midpoint has a third fiber distribution comprising a third amount of regenerated cellulose fibers less than the first fiber distribution but more than the second fiber distribution, and a third amount of cellulose pulp fibers more than the first fiber distribution but less than the second fiber distribution.

[0029] According to certain embodiments of the present invention, multiple regenerated cellulose fibers may include short fibers, such as crimped short fibers, non-crimped short fibers, or combinations thereof.

[0030] According to certain embodiments of the invention, the nonwoven fabric may be free of spunbond fibers, such as spunbond fibers comprising non-plant-based polymers (e.g., petroleum-based fibers). Additionally or alternatively, the nonwoven fabric may be free of meltblown fibers, such as meltblown fibers comprising non-plant-based polymers (e.g., petroleum-based fibers). Additionally or alternatively, the nonwoven fabric may be free of short fibers comprising non-plant-based polymers (e.g., petroleum-based fibers). Additionally or alternatively, the nonwoven fabric may be free of thermal bonding. Additionally or alternatively, the nonwoven fabric may be free of adhesives, such as adhesion promoters, adhesive binders, and adhesive coatings.

[0031] According to certain embodiments of the present invention and as follows Figure 1As shown, the plant-based nonwoven fabric 1 may have a thickness 140 in the z-direction perpendicular to both the longitudinal and transverse directions, wherein the thickness 140 is measured by the shortest imaginary line from a first imaginary plane 110 associated with a first side of the plant-based nonwoven fabric to a second imaginary plane 120 associated with a second side of the plant-based nonwoven fabric, and wherein the thickness may be from about 0.3 to about 1.2 mm in a relaxed state (i.e., without external load applied), for example, at least about any of the following in a relaxed state: 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, and 0.75 mm, and / or at most about any of the following in a relaxed state: 1.2, 1.1, 1.0, 0.95, 0.9, 0.85, 0.8, and 0.75 mm. Additionally or alternatively, the initial percentage of compression in the z-direction of the plant-based nonwoven fabric based on its thickness in the relaxed state under a 2N load may not exceed about 30% (e.g., the percentage reduction in thickness relative to the relaxed state), for example, at least about any of the following thicknesses based on the relaxed state under a 2N load: 3, 5, 8, 10, 12, and 15%, and / or at most about any of the following thicknesses based on the relaxed state under a 2N load: 30, 28, 25, 22, 20, 18, 16, and 15%. Additionally or alternatively, the plant-based nonwoven fabric may have a first bulky rebound percentage based on the first rebound thickness measured after removing the 2N load compared to the thickness in the relaxed state (e.g., the thickness in the relaxed state after removing the load as a percentage of the thickness before compression / initially in the relaxed state), wherein the first bulky rebound percentage is about 70% to about 98% of the thickness in the relaxed state, for example, at least about any one of the following: 70, 72, 75, 78 and 80% of the thickness in the relaxed state, and / or at most about any one of the following: 98, 95, 92, 90, 88, 86, 85, 84, 82 and 80% of the thickness in the relaxed state. Additionally or alternatively, the initial percentage of compression in the z-direction of the plant-based nonwoven fabric based on its thickness in the relaxed state under a 3N load may not exceed about 30% (e.g., the percentage reduction in thickness relative to the relaxed state), for example, at least about any of the following thicknesses based on the relaxed state under a 3N load: 3, 5, 8, 10, 12, and 15%, and / or at most about any of the following thicknesses based on the relaxed state under a 3N load: 30, 28, 25, 22, 20, 18, 16, and 15%.Additionally or alternatively, the plant-based nonwoven fabric may have a first bulky rebound percentage (e.g., the percentage of the thickness in the relaxed state after removing the load to the thickness before compression / initially in the relaxed state) based on a first rebound thickness measured after removing the 3N load compared to the thickness in the relaxed state, wherein said first bulky rebound percentage is about 70% to about 95% of the thickness in the relaxed state, for example, at least about any one of the following: 70, 72, 75, 78 and 80% of the thickness in the relaxed state, and / or up to more than any one of the following: 95, 93, 92, 90, 88, 86, 85, 84, 82 and 80% of the thickness in the relaxed state. Additionally or alternatively, the initial percentage of compression in the z-direction of the plant-based nonwoven fabric based on its thickness in the relaxed state under a 4N load may not exceed about 35% (e.g., the percentage reduction in thickness relative to the relaxed state), for example, at least about any of the following thicknesses based on the relaxed state under a 4N load: 3, 5, 8, 10, 12, 15, 18, and 20%, and / or at most about any of the following thicknesses based on the relaxed state under a 4N load: 35, 32, 30, 28, 25, 22, and 20%. Additionally or alternatively, the plant-based nonwoven fabric may have a first bulky rebound percentage (e.g., the percentage of the thickness in the relaxed state after removing the load to the thickness before compression / initially in the relaxed state) based on a first rebound thickness measured after removing the 4N load compared to the thickness in the relaxed state (e.g., the percentage of the thickness in the relaxed state after removing the load to the thickness in the pre-compression / initial relaxed state), wherein the first bulky rebound percentage is about 70% to about 95% of the thickness in the relaxed state, for example, at least about any one of the following: 70, 72, 75, 78, and 80% of the thickness in the relaxed state, and / or at most about any one of the following: 95, 93, 92, 90, 88, 86, 85, 84, 82, and 80% of the thickness in the relaxed state. Each thickness measurement may be based on... Figure 1 The methods shown and the schemes outlined in the Examples section below.

[0032] According to certain embodiments of the invention, the nonwoven fabric may have a longitudinal (MD) tensile strength of about 12 to about 25 pounds as determined by ASTM D5729, for example, at least about any of the following as determined by ASTM D5729: 12, 14, 15, 16, 18, and 20 pounds, and / or at most about any of the following as determined by ASTM D5729: 25, 24, 22, and 20 pounds. Additionally or alternatively, the nonwoven fabric may have a first ratio between the longitudinal tensile strength (pounds) and the thickness (mm) of the nonwoven fabric in a relaxed state, which is about 20 to about 40, for example, at least about any of the following: 20, 22, 24, 25, 26, 28, and 30; and / or at most about any of the following: 40, 38, 36, 35, 34, 32, and 30. Additionally or alternatively, the nonwoven fabric may have a longitudinal elongation at break of about 3 to about 10% as determined by ASTM D5729, for example, at least about any of the following as determined by ASTM D5729: 3, 4, 5, and 6%, and / or at most about any of the following as determined by ASTM D5729: 10, 9, 8, 7, and 6%. Additionally or alternatively, the nonwoven fabric may have a second ratio between the longitudinal elongation (%) and the thickness (mm) of the nonwoven fabric in a relaxed state, which is at most about 20, for example, at least about any of the following: 5, 6, 8, and 10; and / or at most about any of the following: 20, 18, 16, 15, 14, 12, and 10.

[0033] According to certain embodiments of the invention, the nonwoven fabric may have a dry tabor value of about 15 to about 30 cycles as determined according to ASTM D3884 (smooth surface), for example, at least about any one of the following: 15, 16, 19, and 20 cycles, and / or at most about any one of the following: 30, 28, 26, 25, 24, 22, and 20 cycles. Additionally or alternatively, the nonwoven fabric may have a dry tabor value of about 15 to about 30 cycles as determined according to ASTM D3884 (smooth surface), for example, at least about any one of the following: 15, 16, 19, and 20 cycles, and / or at most about any one of the following: 30, 28, 26, 25, 24, 22, and 20 cycles. Additionally or alternatively, the nonwoven fabric may have a dry Taber abrasion value / basis weight (cycles / gsm) ratio of about 0.2 to about 0.6, for example at least about any of the following: 0.2, 0.22, 0.25, 0.28, 0.3, 0.32, 0.35, 0.38 and 0.4, and / or at most about any of the following: 0.6, 0.58, 0.5, 0.52, 0.5, 0.48, 0.45, 0.42 and 0.4. Additionally or alternatively, the nonwoven fabric may have a wet Tyber abrasion resistance of about 45 to about 70 cycles as determined according to ASTM D3884 (smooth surface), for example at least about any one of the following: 45, 46, 48, 50, 52, 54, 55 and 56 cycles, and / or at most about any one of the following: 70, 68, 65, 62, 60, 58 and 56 cycles.

[0034] According to certain embodiments of the invention, the 3D image includes a 3D pattern on at least a first side of the plant-based nonwoven fabric (and typically on both outer sides of the plant-based nonwoven fabric, as described above), and includes a plurality of recessed portions in the z-direction relative to an imaginary central plane extending through the plant-based nonwoven fabric in an xy-plane perpendicular to the z-direction. Additionally or alternatively, the 3D image includes a 3D pattern on a first side of the plant-based nonwoven fabric (and typically on both outer sides of the composite nonwoven fabric), and includes a plurality of raised portions in the z-direction relative to an imaginary central plane extending through the composite nonwoven fabric in an xy-plane perpendicular to the z-direction.

[0035] According to certain embodiments of the invention, the plurality of recessed portions may have an average depth of about 0.5 mm to about 3 mm, measured from an imaginary central plane, for example, up to about any of the following: 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.8, 1.6 and 1.5 mm, and / or at least about any of the following: 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4 and 1.5 mm. Additionally or alternatively, the plurality of recessed portions may have a width of the shortest distance measured along an imaginary central plane perpendicular to the z-direction, the width being from about 0.2 mm to about 3 mm, for example at most about any of the following: 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.8, 1.6 and 1.5 mm, and / or at least about any of the following: 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4 and 1.5 mm.

[0036] According to certain embodiments of the invention, the plurality of protrusions may have an average height of about 0.5 mm to about 3 mm, measured from an imaginary central plane, for example, up to about any of the following: 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.8, 1.6 and 1.5 mm, and / or at least about any of the following: 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4 and 1.5 mm. Additionally or alternatively, the plurality of recessed portions have a width of the shortest distance measured along an imaginary central plane perpendicular to the z-direction, the width being from about 0.2 mm to about 3 mm, for example at most about any of the following: 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.8, 1.6 and 1.5 mm, and / or at least about any of the following: 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4 and 1.5 mm.

[0037] In another aspect, the present invention provides a method for producing plant-based nonwoven fabrics, such as those described and disclosed herein. The method may include the steps of: (i) providing or forming a carded web or carded fabric comprising a plurality of regenerated cellulose fibers; (ii) depositing a plurality of cellulose pulp fibers onto the carded web or carded fabric to form an intermediate nonwoven material; and (iii) mechanically entangled the plurality of regenerated cellulose fibers and the plurality of cellulose pulp fibers together to provide the plant-based nonwoven fabric. According to certain embodiments of the invention, the method includes forming a three-dimensional (3D) image in a first and / or second side of the plant-based nonwoven fabric.

[0038] According to certain embodiments of the invention, the step of forming a 3D image includes placing an intermediate nonwoven material adjacent to a 3D imaging device (e.g., a roller) and subjecting the intermediate nonwoven material to at least one flow of fluid.

[0039] Suitable three-dimensional imaging devices (e.g., rollers) may include imaging sleeves, such as those described in RE38,105 and RE38,505, the entire contents of which are incorporated herein by reference. For example, plant-based nonwoven fabrics may include a three-dimensional image formed therein, which may be formed throughout the entire plant-based nonwoven fabric. For example, image transfer devices may include one or more rollers, or even one or more sleeves attached to the respective rollers. For example, one or more water jets may be applied to the side of the nonwoven fabric opposite to the side contacting the image transfer device. It is not desired to be bound by theory to think that guiding one or more jets of fluid (e.g., water) through the nonwoven fabric causes the fibers of the nonwoven fabric to be displaced according to an image on the image transfer device (e.g., an image formed on one or more rollers or one or more sleeves attached to the respective rollers), thereby forming a three-dimensional pattern on the entire nonwoven fabric according to that image. Such imaging techniques are further described in, for example, U.S. Patent No. 6,314,627 (titled "Hydraulic Nonwoven Fabric with Structured Surface"), U.S. Patent No. 6,735,833 (titled "Nonwoven Fabric with Durable Three-Dimensional Image"), U.S. Patent No. 6,903,034 (titled "Hydraulic Entanglement of Continuous Polymer Filaments"), U.S. Patent No. 7,091,140 (titled "Hydraulic Entanglement of Continuous Polymer Filaments"), and U.S. Patent No. 7,406,755 (titled "Hydraulic Entanglement of Continuous Polymer Filaments"), each of which is incorporated herein by reference in its entirety. As mentioned above, the at least one fluid stream can be liquid water.

[0040] According to certain embodiments of the invention, at one or more hydroentanglement imaging stations associated with the step of forming a 3D image onto a nonwoven fabric, at least one stream of fluid can be discharged from at least one fluid nozzle at an average pressure of about 25 bar to about 65 bar, for example at least about any of the following: 25, 30, 35, 40 and 45 bar, and / or at most about any of the following: 65, 60, 55, 50 and 45 bar. The average pressure can be associated with one or more fluid nozzles from a single hydroentanglement imaging station or from one or more fluid nozzles from multiple hydroentanglement imaging stations (e.g., 2, 3, 4, 5 or 6 hydroentanglement stations). By way of example only, the step of forming a 3D image onto a nonwoven fabric can be performed at three (3) independent hydroentanglement imaging stations, including a first hydroentanglement imaging station with a discharge pressure of 55 bar, a second hydroentanglement imaging station with a discharge pressure of 55 bar, and a third hydroentanglement imaging station with a discharge pressure of 35 bar. In this case, the average pressure is considered to be about 48.3 bar.

[0041] As previously described, prior to the step of forming a 3D image onto a nonwoven fabric, the fibers (e.g., total fiber content) can be pre-entangled at one or more pre-imaging hydroentanglement stations. In this regard, the pressure of at least one stream of fluid discharged from at least one fluid nozzle of one or more pre-imaging hydroentanglement stations (e.g., 2, 3, 4, 5, or 6 pre-imaging hydroentanglement stations) can be from about 15 bar to 120 bar, for example at least about any of the following: 15, 18, 20, 22, 25, 30, 35, 40, and 50 bar, and / or at most about any of the following: 120, 110, 100, 90, 80, 70, 60, and 50 bar. As an example, pre-entanglement (e.g., prior to imaging) can be performed at three (3) separate pre-imaging hydroentanglement stations, including a first pre-imaging hydroentanglement station with an exhaust pressure of 65 bar, a second pre-imaging hydroentanglement station with an exhaust pressure of 90 bar, and a third pre-imaging hydroentanglement station with an exhaust pressure of 100 bar. In this case, the average pressure is considered to be approximately 85 bar.

[0042] According to certain embodiments of the invention, the ratio of the average fluid pressure at the hydroentanglement imaging station to the average fluid pressure at the hydroentanglement entanglement station before imaging is about 0.2:1 to about 0.8:1, for example at least about any one of the following: 0.2:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1 and 0.55:1, and / or at most about any one of the following: 0.8:1, 0.75:1, 0.7:1, 0.65:1, 0.6:1 and 0.55:1.

[0043] According to certain embodiments of the present invention, the step of depositing multiple cellulose pulp fibers onto a carded web or carded fabric includes air-forming the multiple cellulose pulp fibers onto the carded web or carded fabric. According to certain embodiments of the present invention, the layer of multiple cellulose pulp fibers may be directly impacted by at least one fluid flow, while the carded web or carded fabric is placed directly adjacent to the 3D imaging device (e.g., an imaging sleeve).

[0044] Figure 2 This is a flowchart illustrating certain methods for producing plant-based nonwoven fabric 1 according to certain embodiments of the present invention, wherein the method includes the following steps: (i) providing or forming a carded web or carded fabric comprising a plurality of regenerated cellulose fibers in operation 10; (ii) depositing a plurality of cellulose pulp fibers onto the carded web or carded fabric in operation 20 to form an intermediate nonwoven material; (iii) mechanically entangled the plurality of regenerated cellulose fibers and the plurality of cellulose pulp fibers together through one or more pre-imaging hydroentanglement stations in operation 30 to form a plant-based nonwoven fabric; and (iv) forming a 3D image onto a first and / or second side of the plant-based nonwoven fabric through one or more hydroentanglement imaging stations in operation 40.

[0045] In another aspect, the present invention provides a wiping cloth comprising a plant-based nonwoven fabric (such as those described and disclosed herein) and a liquid additive disposed on or within a first outer surface and / or a second outer surface of the plant-based nonwoven fabric. For example, the liquid additive may comprise an antimicrobial compound, such as a quaternary ammonium compound, a triclosan compound, a zinc pyrithione compound, silver nanoparticles, or any combination thereof. Additionally or alternatively, the liquid additive may comprise a cleaning composition comprising one or more emulsifiers, one or more detergents, one or more surfactants, one or more soaps, or any combination thereof.

[0046] According to certain embodiments of the invention, the wiping wipe may be disposed within a container. For example, the wiping wipe may comprise a continuous material including multiple perforated lines forming dividing lines to define individual sheets or wiping wipes. Alternatively, the wiping wipe may comprise multiple individually separated sheets or wiping wipes, allowing a user to directly take a single individual wiping wipe without separating it from other sheets or wiping wipes.

[0047] Example This disclosure is further illustrated by the following embodiments, which should not be construed as limiting. That is, the specific features described in the following embodiments are merely illustrative and not restrictive.

[0048] [Example Group 1] A 48.7 gsm plant-based nonwoven fabric was compared with a 61.2 gsm paper wipe to illustrate the improved resilience of the plant-based nonwoven fabric according to certain embodiments of the invention. The plant-based nonwoven fabric is formed from 50 wt% cellulose pulp and 50 wt% lyocell short fibers, wherein the cellulose pulp and lyocell short fibers are hydroentangled together to provide the plant-based nonwoven fabric. The hydroentanglement operation is performed as follows: (i) pre-imaging entanglement pressure (in the direction of travel): 45, 65, 90, and 100 psi; and (ii) imaging pressure (in the direction of travel): 55, 55, and 35 psi. The speed is 200 mpm (e.g., a commercial production line), and the imaging energy is 0.0205 HP / Hr / Lb.

[0049] Bulk resilience was measured using a TA Instruments ARES-G2 rheometer. The rheometer was fitted with a 25 mm parallel plate stainless steel clamp, and all measurements were performed at room temperature (23°C ± 10°C). A 30 mm x 30 mm sample was placed between the parallel plates, and the initial thickness was measured using a force of 0.245 N. A compressive force was then applied for 30 seconds, and the thickness was recorded. The force was then removed, allowing the sample to relax. The thickness was then measured again using a force of 0.245 N to calculate the recovery rate. The recovery rate was measured at three different compressive forces (2 N, 3 N, and 4 N), each using fresh samples. The last three columns of Table 1 (i.e., the last three columns on the right side of Table 1) have been normalized to the sample basis weight (i.e., the percentage divided by the sample basis weight). Figure 3 The percentage of thickness recovery of plant-based nonwoven fabrics compared to paper wipes is graphically presented. In this respect, depending on the compressive force, the resilience of plant-based nonwoven fabrics is approximately 26% to approximately 38% higher than that of paper wipes. For example, for the 2N sample, the thickness recovery rate (D to A) of the plant-based nonwoven fabric was 20.0%, while that of the paper wipe was 12.8%, indicating that the plant-based nonwoven fabric achieved a 36% higher resilience.

[0050] Table 1 .

[0051] Regarding the data in Table 1, the plant-based nonwoven fabrics have a first loft rebound percentage based on the thickness before and after compression (i.e., the thickness in the relaxed state after removing the load is the same as the thickness before compression, expressed as (A / B)*100 in Table 1), and the results are as follows: 95.5% under 2N force; 93.1% under 3N force; 91.9% under 4N force.

[0052] The aforementioned plant-based nonwoven fabrics were also compared with 100% rayon nonwoven wipes under the same conditions. The comparison data under a 3N load are summarized in Table 2, where the last column of Table 2 has been normalized by the basis weight of the samples (i.e., the percentage of each sample divided by the basis weight of the sample). Figure 4 The data (i.e., the percentage of thickness recovery normalized to basis weight) for plant-based nonwoven fabrics is graphically presented compared to 100% rayon nonwoven wipes. Compared to 100% rayon nonwoven wipes, the total thickness loss of plant-based nonwoven fabrics is reduced by 8% when normalized to basis weight.

[0053] Table 2 .

[0054] [Example Group 2] The effect of fluid pressure on spunlace plant-based nonwoven fabrics is shown in Table 3. In this regard, Sample 1 (labeled BB-2201 in Table 3) represents spunlace entanglement performed at a “higher” fluid pressure, impacting the fibers of the material being consolidated, while Sample 2 (labeled BB-2110 in Table 3) represents spunlace entanglement performed at a lower fluid pressure, impacting the fibers of the material being consolidated. Specifically, for Sample 1, the pre-imaging entanglement pressures used along the direction of travel were 45, 65, 90, and 100 psi, while the imaging pressures used along the direction of travel were 55, 55, and 35 psi. As shown in Table 3, using a “lower” pressure for spunlace entanglement imparts certain improvements to the desired physical properties. For example, using a lower spunlace entanglement fluid pressure provides a significant increase in dry machine direction tension (MDT) and a decrease in dry machine direction elongation (MDE). Furthermore, lower hydroentanglement fluid pressure provides statistically significantly softer nonwoven fabrics in both the longitudinal and transverse directions. For example, using lower hydroentanglement fluid pressure, the number of dry-state Tite abrasion cycles (smooth surface) increased by 49.3%, and the number of wet-state Tite abrasion cycles (smooth surface) increased by 16.7%.

[0055] Table 3 .

[0056] These and other modifications and alterations can be made to the invention by those skilled in the art without departing from the spirit and scope of the invention, which are more specifically set forth in the appended claims. Furthermore, it should be understood that aspects of the various embodiments can be interchanged, in whole or in part. Moreover, those skilled in the art will understand that the foregoing description is merely exemplary and is not intended to limit the invention as further described in the appended claims. Therefore, the spirit and scope of the appended claims should not be limited to the exemplary descriptions of the versions contained herein.

Claims

1. A plant-based nonwoven fabric, comprising: Multiple regenerated cellulose fibers physically entangled with multiple cellulose pulp fibers; wherein the nonwoven fabric has a first side and a second side, and the first side and / or the second side has a three-dimensional (3D) image formed therein, wherein the 3D image includes multiple recessed portions and multiple raised portions.

2. The nonwoven fabric according to claim 1, wherein the plurality of regenerated cellulose fibers comprises viscose fiber, rayon fiber, acetate fiber, triacetate fiber, modal fiber, lyocell fiber, or any combination thereof.

3. The nonwoven fabric according to claim 2, wherein the plurality of regenerated cellulose fibers are a blend of rayon fibers and lyocell fibers, wherein the lyocell fibers comprise about 30 to about 95% by weight of the blend, for example, at least about any one of the following: 30, 40 and 50% by weight of the blend, and / or at most about any one of the following: 95, 90, 85, 80, 75, 70, 65, 60, 55 and 50% by weight of the blend.

4. The nonwoven fabric of claim 1, wherein the nonwoven fabric has a total fiber content, and the plurality of regenerated cellulose fibers account for about 20 to about 80% by weight of the total fiber content, for example, at least about any one of the following: 20, 25, 30, 35, 40 and 45% by weight of the total fiber content, and / or at most about any one of the following: 80, 75, 70, 65, 60, 55, 50 and 45% by weight of the total fiber content.

5. The nonwoven fabric according to claim 1 further comprises multiple polylactic acid fibers, wherein the multiple polylactic acid fibers (i) are physically entangled with the multiple regenerated cellulose fibers and the multiple cellulose pulp fibers, or (ii) are located on the first side and / or the second side.

6. The nonwoven fabric according to claim 1, wherein the first side has a first fiber distribution and the second side has a second fiber distribution different from the first fiber distribution, wherein (i) the first fiber distribution includes a first amount of the plurality of regenerated cellulose fibers in a quantity greater than a first amount of the plurality of cellulose pulp fibers, and (ii) the second fiber distribution includes a second amount of the plurality of regenerated cellulose fibers in a quantity less than a second amount of the plurality of cellulose pulp fibers.

7. The nonwoven fabric of claim 1, wherein the nonwoven fabric has a thickness in the z-direction perpendicular to the longitudinal and transverse directions, wherein the thickness is measured by the shortest imaginary line from a first imaginary plane associated with the first side to a second imaginary plane associated with the second side, and wherein the thickness is from 0.3 mm to about 1.2 mm in a relaxed state, for example, at least about any of the following in a relaxed state: 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, and 0.75 mm, and / or at most about any of the following in a relaxed state: 1.2, 1.1, 1.0, 0.95, 0.9, 0.85, 0.8, and 0.75 mm.

8. The nonwoven fabric of claim 7, wherein the initial compression percentage of the nonwoven fabric in the z-direction based on the thickness in the relaxed state under a 2N load is no greater than about 30%, for example, at least about any one of the following thicknesses under a 2N load based on the relaxed state: 3, 5, 8, 10, 12 and 15%, and / or at most about any one of the following thicknesses under a 2N load based on the relaxed state: 30, 28, 25, 22, 20, 18, 16 and 15%.

9. The nonwoven fabric of claim 8, wherein the nonwoven fabric has a first fluffy rebound percentage based on a first rebound thickness measured after removing a 2N load compared to the thickness in the relaxed state, wherein the first fluffy rebound percentage is about 70% to about 98% of the thickness in the relaxed state, for example, at least about any one of the following: 70, 72, 75, 78 and 80% of the thickness in the relaxed state, and / or at most about any one of the following: 98, 95, 92, 90, 88, 86, 85, 84, 82 and 80% of the thickness in the relaxed state.

10. The nonwoven fabric of claim 1, wherein the nonwoven fabric has a longitudinal tensile strength of about 12 to about 25 pounds as determined by ASTM D5729, for example, at least about any one of the following as determined by ASTM D5729: 12, 14, 15, 16, 18 and 20 pounds, and / or at most about any one of the following as determined by ASTM D5729: 25, 24, 22 and 20 pounds; and a first ratio between the longitudinal tensile strength in pounds and the thickness of the nonwoven fabric in the relaxed state in mm is about 20 to about 40, for example, at least about any one of the following: 20, 22, 24, 25, 26, 28 and 30; and / or at most about any one of the following: 40, 38, 36, 35, 34, 32 and 30.

11. The nonwoven fabric of claim 1, wherein the nonwoven fabric has a longitudinal elongation at break of about 3 to about 10% as determined by ASTM D5729, for example, at least about any one of the following as determined by ASTM D5729: 3, 4, 5 and 6%, and / or at most about any one of the following as determined by ASTM D5729: 10, 9, 8, 7 and 6%; and a second ratio between the longitudinal elongation in percentage and the thickness of the nonwoven fabric in mm at relaxation state is at most about 20, for example, at least about any one of the following: 5, 6, 8 and 10; and / or at most about any one of the following: 20, 18, 16, 15, 14, 12 and 10.

12. The nonwoven fabric of claim 1, wherein the nonwoven fabric has a dry Talber abrasion resistance of about 15 to about 30 cycles as determined according to ASTM D3884 for a smooth surface, for example at least about any one of the following: 15, 16, 19 and 20 cycles, and / or at most about any one of the following: 30, 28, 26, 25, 24, 22 and 20 cycles; and a dry Talber abrasion resistance / basis weight ratio in cycles / gsm is about 0.2 to about 0.6, for example at least about any one of the following: 0.2, 0.22, 0.25, 0.28, 0.3, 0.32, 0.35, 0.38 and 0.4, and / or at most about any one of the following: 0.6, 0.58, 0.5, 0.52, 0.5, 0.48, 0.45, 0.42 and 0.

4.

13. The nonwoven fabric of claim 1, wherein the nonwoven fabric has a wet Taber abrasion resistance of about 45 to about 70 cycles as determined according to ASTM D3884 for a smooth surface, for example at least about any one of the following: 45, 46, 48, 50, 52, 54, 55 and 56 cycles, and / or at most about any one of the following: 70, 68, 65, 62, 60, 58 and 56 cycles.

14. A method for producing plant-based nonwoven fabrics, comprising: (i) Providing or forming a combed web or combed fabric containing multiple regenerated cellulose fibers; (ii) Depositing multiple cellulose pulp fibers onto the carded web or carded fabric to form an intermediate nonwoven material; (iii) Mechanically entangle the plurality of regenerated cellulose fibers and the plurality of cellulose pulp fibers together to provide the plant-based nonwoven fabric.

15. A wiping cloth, comprising: (i) The plant-based nonwoven fabric according to claim 1; as well as (ii) Liquid additives disposed on or inside the first and / or second outer surfaces of the wiping cloth.

Images