Patent Application
20250179700
Embodiments of the presently-disclosed invention relate generally to a plant-based nonwoven fabric include a plurality of regenerated cellulose fibers physically entangled with a plurality of cellulose pulp fibers, in which the first side and/or the second side of the nonwoven fabric has a three-dimensional (3D) image formed therein.
The use of natural fiber materials in industrial applications, such as absorbent pads or wipes, has gained increased interest as an environmentally positive approach to the formation of nonwoven fabrics. However, it is typical for a 100% cellulose product to wad up or bunch up and not rebound in shape when wet. For example, some traditional approaches to plant-based nonwoven fabrics formed from 100% cellulosic fibers include carded hydroentangled rayon without an image (flat) or a very light belt image. Other approaches employ a three-layer fabric formed from a carded rayon/an air-laid pulp/a carded rayon (CPC) with a flat or wire image. Due, at least in part, to the traditional shortcomings of plant-based nonwoven fabrics in which the entirety of the fibers are formed from a plant-based material (e.g., cellulosic fibers), some wipes offset such shortcomings by incorporating a significant amount of petroleum based fibers (e.g., polyolefin spunbond fibers) with the cellulosic fibers.
One or more embodiments of the invention may address one or more of the aforementioned problems. Certain embodiments according to the invention provide a plant-based nonwoven fabric including a plurality of regenerated cellulose fibers physically entangled with a plurality of 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 a plurality of recessed portions and a plurality of raised.
In another aspect, the present invention provides a process for producing a plant-based nonwoven fabric such as those described and disclosed herein. The process may comprise the following steps: (i) providing or forming a carded web or carded fabric comprising a plurality of regenerated cellulose; (ii) depositing a plurality of cellulose pulp fibers onto the carded web or carded fabric to form an intermediate nonwoven material; and (iii) mechanically entangling the plurality of regenerated cellulose and the plurality of cellulose pulp fibers together to provide the plant-based nonwoven fabric.
In another aspect, the present invention provides a wipe including a plant-based nonwoven fabric, such as those described and disclosed herein, a liquid additive disposed onto or within a first outer surface and/or a second outer surface of the plant-based nonwoven fabric.
The invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, this 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 so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout, and wherein:
The invention now will be described more fully hereinafter. Indeed, this 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 so that this disclosure will satisfy applicable legal requirements. As used in the specification, and in the appended claims, the singular forms “a”, “an”, “the”, include plural referents unless the context clearly dictates otherwise.
Certain embodiments of the invention may be directed to a plant-based nonwoven fabric, such as in the form of a wet or dry wipe, which is formed significantly or completely from plant-based fibers. For example, the plant-based nonwoven fabric may comprise a total fiber content that is 100% plant-based fibers. The plant-based fibers may be hydroentangled (or otherwise mechanically entangled together). The plant-based nonwoven fabric, for instance, may be formed from one or more different types of plant-based fibers (e.g., cellulosic fibers). In accordance with certain embodiments of the invention, the plant-based nonwoven fabric may exhibit or have a particularly desirable wet rebound, particularly for a plant-based nonwoven fabric. Unlike certain embodiments of the present invention, it fairly typical for traditional 100% cellulose products to wad up and not rebound when wet. As such, the wet rebound associated with the plant-based nonwoven fabrics described and disclosed herein provides a significantly desirable benefit to, at least, the wipes industry.
In accordance with certain embodiments of the invention, the plant-based nonwoven fabric may be formed from a carded layer of lyocell fibers and a layer of air-laid pulp that have been hydroentangled together. These layers may be hydroentangled in one or more hydroentangling stations. For example, a first station or first group of hydroentangling stations, for example on a non-image forming surface, may hydroentangle the lyocell fiber and the air-laid pulp together to impart enough structural integrity for a second station or second group of hydroentangling stations that further hydroentangles the fibers together (i) at a lower average fluid pressure, and (ii) on an imaging roll or device to impart a substantial three-dimensional (3D) image into the plant-based nonwoven fabric. In this regard, the 3D image is formed and/or defined by the orientation of the respective fibers at a first and/or second outer surface. By way of example, the first outer surface having the 3D image may have one or more raised portions thereon at selected positions, while the second outer surface may have corresponding one or more recessed portions at the selected positions. That is, a location on the first outer surface may have a raised region while the backside of the plant-based nonwoven fabric may have a corresponding recessed region. By way of further example, the one or more raised regions of the 3D image of the first outer surface may comprise a logo extending outwardly from the first outer surface, while the backside of the plant-based nonwoven fabric will have the logo recessed and extending inwardly towards the first outer surface. That is, projections on a first outer surface may be associated with or correspond to recessed portions in the second (opposite) outer surface.
Without wishing to be bound to theory, it is believed that the combination of the 3D imaging, the lyocell fibers (e.g., higher wet-strength), as-well-as the manner in which the cellulose pulp fibers are incorporated into the carded layer of regenerated cellulose fibers (e.g., lyocell fibers) contributes to the wet rebound associated with certain embodiments of the present invention. For example, the pulp cellulose fibers are incorporated into the carded layer in a way that provides Tabor abrasions that are in line with more traditionally durable fabrics as compared to a typical hydroentangled nonwoven fabric. For example, it is believed that a lower fluid pressure during the final hydroentangling operation to entangle the plurality of regenerated cellulose fibers (e.g., lyocell fibers) and the cellulose pulp fibers surprisingly creates a stronger more durable nonwoven fabric when compared to the same nonwoven fabric made at higher fluid pressure during the final hydroentangling operation. This results, for example, in higher tensile strengths, lower elongations, and increased Tabor abrasion cycles (e.g., a measure of durability).
The terms “nonwoven” and “nonwoven web”, as used herein, may comprise a web having a structure of individual fibers, fibers, and/or threads that are interlaid but not in an identifiable repeating manner as in a knitted or woven fabric. Nonwoven fabrics or webs, according to certain embodiments of the invention, may be formed by any process conventionally known in the art such as, for example, meltblowing processes, spunbonding processes, needle-punching, hydroentangling, air-laid, and bonded carded web processes. A “nonwoven web”, as used herein, may comprise a plurality of individual fibers that have not been subjected to a consolidating process. In certain instances, the “nonwoven web” may comprises a plurality of layers, such as one or more spunbond layers and/or one or more meltblown layers. For instance, a “nonwoven web” may comprises a spunbond-meltblown-spunbond structure.
The terms “fabric” and “nonwoven fabric”, as used herein, may comprise a web of fibers in which a plurality of the fibers are mechanically entangled or interconnected, fused together, and/or chemically bonded together. For example, a nonwoven web of individually laid fibers may be subjected to a bonding or consolidation process to bond at least a portion of the individually fibers together to form a coherent (e.g., united) web of interconnected fibers.
The term “layer”, as used herein, may comprise a generally recognizable combination of similar material types and/or functions existing in the X-Y plane.
The term “consolidated” and “consolidation”, as used herein, may comprise the bringing together of at least a portion of the fibers of a nonwoven web into closer proximity or attachment there-between (e.g., thermally fused together, chemically bonded together, and/or mechanically entangled together) to form a bonding site, or bonding sites, which function to increase the resistance to external forces (e.g., abrasion and tensile forces), as compared to the unconsolidated web. The bonding site or bonding sites, for example, may comprise a discrete or localized region of the web material that has been softened or melted and optionally subsequently or simultaneously compressed to form a discrete or localized deformation in the web material. Furthermore, the term “consolidated” may comprise an entire nonwoven web that has been processed such that at least a portion of the fibers are brought into closer proximity or attachment there-between (e.g., thermally fused together, chemically bonded together, and/or mechanically entangled together), such as by thermal bonding or mechanical entanglement (e.g., hydroentanglement) as merely a few examples. Furthermore, the term “consolidated” and “consolidation” may comprise the bonding by means of a through-air-bonding operation. The term “through-air bonded” and “though-air-bonding”, as used herein, may comprise a nonwoven web consolidated by a bonding process in which hot air is used to fuse the fibers at the surface of the web and optionally internally within the web. By way of example only, hot air can either be blown through the web in a conveyorized oven or sucked through the web as it passes over a porous drum as a vacuum is developed. The temperature of and the rate of hot air are parameters that may determine the level or the extent of bonding in nonwoven web. In accordance with certain embodiments of the invention, the temperature of the hot air may be high enough to melt, induce flowing, and/or fuse the a plurality of fibers having a lower melting point temperature or onset of lower melting point temperature (e.g., amorphous fibers) to a plurality of fibers having a higher melting point temperature or onset of lower melting point temperature (e.g., semi-crystalline or crystalline fibers). Such a web may be considered a “consolidated nonwoven”, “nonwoven fabric” or simply as a “fabric” according to certain embodiments of the invention.
The term “machine direction” or “MD”, as used herein, comprises the direction in which the fabric produced or conveyed. The term “cross-direction” or “CD”, as used herein, comprises the direction of the fabric substantially perpendicular to the MD.
The term “cellulosic fiber”, as used herein, may comprise fibers derived from hardwood trees, softwood trees, or a combination of hardwood and softwood trees prepared for use in, for example, a papermaking furnish and/or fluff pulp furnish by any known suitable digestion, refining, and bleaching operations. The cellulosic fibers may comprise recycled fibers and/or virgin fibers. Recycled fibers differ from virgin fibers in that the fibers have gone through the drying process at least once. In certain embodiments, at least a portion of the cellulosic fibers may be provided from non-woody herbaceous plants including, but not limited to, kenaf, cotton, hemp, jute, flax, sisal, or abaca. Cellulosic fibers may, in certain embodiments of the invention, comprise either bleached or unbleached pulp fiber such as high yield pulps and/or mechanical pulps such as thermo-mechanical pulping (TMP), chemical-mechanical pulp (CMP), and bleached chemical-thermo-mechanical pulp BCTMP. In this regard, the term “pulp”, as used herein, may comprise cellulose that has been subjected to processing treatments, such as thermal, chemical, and/or mechanical treatments. Cellulosic fibers, according to certain embodiments of the invention, may comprise one or more regenerated cellulose fibers (e.g., viscose, rayon, lyocell fibers, etc.). Cellulosic fibers, according to certain embodiments of the invention, may comprise one or more pulp materials (e.g., cellulose pulp fibers).
As used herein, the term “fiber” may refer to a staple fiber, a meltblown fiber, and/or a continuous spunbond filament. In this regard, the use of the term “spunbond fiber” may be used interchangeably with “spunbond filament”. A fiber typically means an elongate particulate having an apparent length exceeding its apparent width, substantially exceeding according to certain embodiments of the invention.
The term “spunbond”, as used herein, may comprise fibers which are formed by extruding molten thermoplastic material as filaments from a plurality of fine, usually circular, capillaries of a spinneret with the diameter of the extruded filaments then being rapidly reduced. According to an embodiment of the invention, spunbond fibers are generally not tacky when they are deposited onto a collecting surface and may be generally continuous as disclosed and described herein. It is noted that the spunbond used in certain composites of the invention may include a nonwoven described in the literature as SPINLACE®. Spunbond fibers, for example, may comprises continuous fibers.
As used herein, the term “continuous fibers” refers to fibers which are not cut from their original length prior to being formed into a nonwoven web or nonwoven fabric. Continuous fibers, such as spunbond fibers, may have average lengths ranging from greater than about 15 centimeters to more than one meter, and up to the length of the web or fabric being formed. For example, a continuous fiber, as used herein, may comprise a fiber in which the length of the fiber is at least 1,000 times larger than the average diameter of the fiber, such as the length of the fiber being at least about 5,000, 10,000, 50,000, or 100,000 times larger than the average diameter of the fiber.
The term “staple fiber”, as used herein, may comprise a cut fiber from a filament. In accordance with certain embodiments, any type of filament material may be used to form staple fibers. For example, the average length of staple fibers may comprise, by way of example only, from about 2 centimeter to about 15 centimeter, 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.
The term “meltblown”, as used herein, may comprise fibers formed by extruding a molten thermoplastic material through a plurality of fine die capillaries as molten threads or filaments into converging high velocity, usually hot, gas (e.g. air) streams which attenuate the filaments of molten thermoplastic material to reduce their diameter, which may be to microfiber diameter, according to certain embodiments of the invention. According to an embodiment of the invention, the die capillaries may be circular. Thereafter, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a web of randomly disbursed meltblown fibers. Meltblown fibers may comprise microfibers which may be continuous or discontinuous and are generally tacky when deposited onto a collecting surface. Meltblown fibers, however, are shorter in length than those of spunbond fibers.
Certain embodiments according to the invention provide a plant-based nonwoven fabric including a plurality of regenerated cellulose fibers, such as staple fibers, physically entangled with a plurality of 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 a plurality of recessed portions and a plurality of raised. In accordance with certain embodiments of the invention, the plurality of regenerated cellulose fibers may comprise viscose fibers, rayon fibers, acetate fibers, triacetate fibers, modal fibers, lyocell fibers, or any combination thereof.
In accordance with certain embodiments of the invention, the plurality of regenerated cellulose fibers may comprise a blend of rayon fibers and lyocell fibers, wherein the lyocell fibers account for about 30 to about 95% by weight of the blend, such as at least about any of the following: 30, 40, and 50% by weight of the blend, and/or at most about any of the following: 95, 90, 85, 80, 75, 70, 65, 60, 55, and 50% by weight of the blend. Alternatively, the plurality of regenerated cellulose fibers may consist of lyocell fibers (i.e., 100% lyocell fibers).
In accordance with certain embodiments of the invention, the nonwoven fabric may have a total fiber content and the plurality of regenerated cellulose fibers may comprise from about 20 to about 80% by weight of the total fiber content, such as at least about any of the following: 20, 25, 30 35, 40, and 45% by weight of the total fiber content, and/or at most about any 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 comprise from about 20 to about 80% by weight of the total fiber content, such as at least about any of the following: 20, 25, 30 35, 40, and 45% by weight of the total fiber content, and/or at most about any of the following: 80, 75, 70, 65, 60, 55, 50, and 45% by weight of the total fiber content.
Optionally, the nonwoven fabric may include a plurality of polylactic acid fibers, such as spunbond polylactic acid fibers, meltblown polylactic acid fibers, or staple polylactic acid fibers; in which the plurality of polylactic acid fibers are physically entangled with the plurality of regenerated cellulose fibers and the plurality of cellulose pulp fibers. Alternatively, the plurality of polylactic acid fibers may be located on the first side and/or the second side of the nonwoven fabric. For instance, the plurality of polylactic acid fibers may comprise meltblown fibers including “meltblown shot” and/or “meltblown rope” that may provide added texture of abrasiveness to one or both sides of the nonwoven fabric, such as for improving the ability of the nonwoven fabric to provide a scrubbing action for the removal of debris. The term “meltblown shot”, as used herein, may comprise a coarse non-uniform or non-continuous layer applied in a meltblown process deliberately operated to generate random globules of a polymer (e.g., a polylactic acid) interconnected with strands. Moreover, the term “meltblown rope”, as used herein, may also comprise a coarse non-uniform or non-continuous layer applied in a meltblown process deliberately operated to generate random “ropes” or bundles of a polymer interconnected with strands. Meltblown rope differs from meltblown shot in that meltblown rope may be more elongated and/or narrower than meltblown shot. Both the meltblown ropes and/or meltblown shot may comprise irregularly shaped fibers, wads, or particles. In this regard, for example, the meltblown ropes and/or meltblown shot may comprise fibers, wads, particles, or globules having non-circular cross-sections. The meltblown ropes and/or meltblown shot may be randomly and irregularly distributed within the body of a meltblown layer and/or on a surface of a meltblown layer. For example, the meltblown ropes and/or meltblown shot may extend on random paths and may intersect and/or cross at random locations. However, the meltblown ropes and/or meltblown shot may not intersect or cross at all.
In accordance with certain embodiments of the invention, the nonwoven fabric may have a basis weight from about 20 to about 100 grams-per-square-meter (gsm), such as 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.
In accordance with certain embodiments of the invention, the nonwoven fabric includes the first side (e.g., a first outermost side) that has a first fiber profile and the second side (e.g., a second outermost side) has a second fiber profile that is different from the first fiber profile. For example, the first fiber profile includes a first amount of the plurality of regenerated cellulose fibers that is greater by number than a first amount of the plurality of cellulose pulp fibers, and the second fiber profile includes a second amount of the plurality of regenerated cellulose fibers that is less by number than a second amount of the plurality of cellulose pulp fibers. The nonwoven fabric may have a thickness in a z-direction that is perpendicular to a machine direction and a cross-direction and includes a midpoint between the first side and the second side in the z-direction, in which the midpoint includes a third fiber profile having a third amount of the plurality of regenerated cellulose fibers that is less by number than the first fiber profile and greater by number than the second fiber profile, and a third amount of the plurality of cellulose fiber that is greater by number than the first fiber profile and less by number than the second fiber profile.
The plurality of regenerated cellulose fibers, in accordance with certain embodiments of the invention, may comprise staple fibers, such as crimped staple fibers, non-crimped staple fibers, or a combination thereof.
In accordance with certain embodiments of the invention, the nonwoven fabric may be devoid of spunbond fibers, such as spunbond fibers comprising a non-plant based polymer (e.g., a petroleum based fiber). Additionally or alternatively, the nonwoven fabric may be devoid of meltblown fibers, such as meltblown fibers comprising a non-plant based polymer (e.g., a petroleum based fiber). Additionally or alternatively, the nonwoven fabric may be devoid of staple fibers comprising a non-plant based polymer (e.g., a petroleum based fiber). Additionally or alternatively, the nonwoven fabric may be devoid of thermal bond(s). Additionally or alternatively, the nonwoven fabric may be devoid of adhesives, such as adhesive bonding agents, adhesive binders, and adhesive coatings.
In accordance with certain embodiments of the invention and as illustrated in
In accordance with certain embodiments of the invention, the nonwoven fabric may have a machine direction (MD) tensile strength from about 12 to about 25 pounds as determined per ASTM D5729, such as at least about any of the following: 12, 14, 15, 16, 18, and 20 pounds as determined per ASTM D5729, and/or at most about any of the following: 25, 24, 22, and 20 pounds as determined per ASTM D5729. Additionally or alternatively, the nonwoven fabric may have a first ratio between the MD tensile strength (lbs) and the thickness (mm) of the nonwoven fabric in a related state from about 20 to about 40, such as 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, 24, 32, and 30. Additionally or alternatively, the nonwoven fabric may have a machine direction (MD) elongation at break from about 3 to about 10% as determined per ASTM D5729, such as at least about any of the following: 3, 4, 5, and 6% as determined per ASTM D5729, and/or at most about any of the following: 10, 9, 8, 7, and 6% as determined per ASTM D5729. Additionally or alternatively, the nonwoven fabric may have a second ratio between the MD elongation (%) and the thickness (mm) of the nonwoven fabric in a related state of at most about 20, such as 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.
In accordance with certain embodiments of the invention, the nonwoven fabric may have a dry tabor value from about 15 to about 30 cycles per ASTM D3884 (Smooth side), such as at least about any of the following: 15, 16, 19, and 20 cycles, and/or at most about any of the following: 30, 28, 26, 25, 24, 22, and 20 cycles. Additionally or alternatively, the nonwoven fabric may have a dry tabor value from about 15 to about 30 cycles per ASTM D3884 (Smooth side), such as at least about any of the following: 15, 16, 19, and 20 cycles, and/or at most about any of the following: 30, 28, 26, 25, 24, 22, and 20 cycles. Additionally or alternatively, the nonwoven fabric may have a dry tabor-to-basis weight (cycles/gsm) ratio from about 0.2 to about 0.6, such as 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 tabor value from about 45 to about 70 cycles per ASTM D3884 (Smooth side), such as at least about any of the following: 45, 46, 48, 50, 52, 54, 55, and 56 cycles, and/or at most about any of the following: 70, 68, 65, 62, 60, 58, and 56 cycles.
In accordance with certain embodiments of the invention, the 3D image comprises a 3D pattern on at least a first side of the plant-based nonwoven fabric (and usually on both outer sides of the plant-based nonwoven fabric as noted above) and includes a plurality of recessed portions in a z-direction relative to an imaginary central plane extending through the plant-based nonwoven fabric in an x-y plane that is perpendicular to the z-direction. Additionally or alternatively, the 3D image comprises a 3D pattern on a first side of the plant-based nonwoven fabric (and usually on both outer sides of the composite nonwoven fabric) and includes a plurality of elevated portions in a z-direction relative to an imaginary central plane extending through the composite nonwoven fabric in an x-y plane that is perpendicular to the z-direction.
The plurality of recessed portions, in accordance with certain embodiments of the invention, may have an average depth measured from the imaginary central plane from about 0.5 mm to about 3 mm, such as 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, 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 measured as a shortest distance perpendicular to the z-direction along the imaginary central plane from about 0.2 mm to about 3 mm, such as 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, 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.
The plurality of elevated portions, in accordance with certain embodiments of the invention, may have an average height measured from the imaginary central plane from about 0.5 mm to about 3 mm, such as 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, 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 an width measured as a shortest distance perpendicular to the z-direction along the imaginary central plane from about 0.2 mm to about 3 mm, such as 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, 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.
In another aspect, the present invention provides a process for producing a plant-based nonwoven fabric such as those described and disclosed herein. The process may comprise the following steps: (i) providing or forming a carded web or carded fabric comprising a plurality of regenerated cellulose; (ii) depositing a plurality of cellulose pulp fibers onto the carded web or carded fabric to form an intermediate nonwoven material; and (iii) mechanically entangling the plurality of regenerated cellulose and the plurality of cellulose pulp fibers together to provide the plant-based nonwoven fabric. In accordance with certain embodiments of the invention, the process comprises imparting a three-dimensional (3D) image into a first side and/or second side of the plant-based nonwoven fabric.
In accordance with certain embodiments of the invention, the step of imparting the 3D image comprises positioning the intermediate nonwoven material adjacent a 3D imaging device (e.g., roll) and subjecting the intermediate nonwoven material to at least one fluid stream. Suitable three-dimensional imaging devices (e.g., rolls) may comprise imaging sleeves include those described, for example, in RE38,105 and RE38,505, in which the contents of both are hereby incorporated by reference in their entirety. For example, the plant-based nonwoven fabric may include a three-dimensional image formed therein that may be formed throughout the plant-based nonwoven fabric. For example, the image transfer device may comprise one or more drums or even one or more sleeves affixed to a corresponding drum. One or more water jets, for example, may be applied to a side of the nonwoven opposite to the side contacting the image transfer device. Without intending to be bound by the theory, the one or more water jets of fluid (e.g., water) directed through the nonwoven causes the fibers of the nonwoven to become displaced according to the image on the image transfer device such as the image formed on one or more drums or one or more sleeves affixed to a corresponding drum causing a three-dimensional pattern to be imaged throughout the nonwoven according to such image. Such imaging techniques are further described in, for example, U.S. Pat. No. 6,314,627 entitled “Hydroentangled Fabric having Structured Surfaces”; U.S. Pat. No. 6,735,833 entitled “Nonwoven Fabrics having a Durable Three-Dimensional Image”; U.S. Pat. No. 6,903,034 entitled “Hydroentanglement of Continuous Polymer Filaments”; U.S. Pat. No. 7,091,140 entitled “Hydroentanglement of Continuous Polymer Filaments”; and U.S. Pat. No. 7,406,755 entitled “Hydroentanglement of Continuous Polymer Filaments” each of which are hereby incorporated by reference in their entirety herein by reference. As noted above, the at least one fluid stream may be liquid water.
In accordance with certain embodiments of the invention, the at least one fluid stream across one or more hydroentangling imaging stations associated with the step of imparting the 3D image into the nonwoven fabric may be discharged from at least one fluid jet at an average pressure from about 25 bar to about 65 bar, such as 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 may be associated with one or more fluid jets from a single hydroentangling imaging station or one or more fluid jets from a plurality of hydroentangling imaging stations (e.g., 2, 3, 4, 5, or 6 hydroentangling stations). By way of example only, the step of imparting the 3D image into the nonwoven fabric may be accomplished over three (3) separate hydroentangling imaging stations, including a first hydroentantling imaging station having a discharge pressure of 55 bar, a second hydroentangling imaging station having a discharge pressure of 55 bar, and a third hydroentangling imaging station having a discharge pressure of 35 bar. In this regard, the average pressure would be considered to be about 48.3 bar.
As noted previously, prior to the step of imparting the 3D image into the nonwoven fabric, the fibers (e.g., total fiber content) may be pre-entangled across one or more pre-imaging hydroentangling stations. In this regard, the at least one fluid stream discharged from at least one fluid jet from one or more pre-imaging hydroentangling stations (e.g., 2, 3, 4, 5, or 6 pre-imaging hydroentangling stations) may be from about 15 bar to 120 bar, such as 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. By way of example, pre-entanglement (e.g., prior to imaging) may be conducted across three (3) separate pre-imaging hydroentangling stations, including a first pre-imaging hydroentangling station having a discharge pressure of 65 bar, a second pre-imaging hydroentangling station having a discharge pressure of 90 bar, and third pre-imaging hydroentangling station having a discharge pressure of 100 bar. In this regard, the average pressure would be considered to be about 85 bar.
In accordance with certain embodiments of the invention, a ratio between the average fluid pressure of the hydroentangling imaging station(s) to the average fluid pressure of the pre-imaging hydroentangling stations comprises from about 0.2:1 to about 0.8:1, such as at least about any 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 of the following: 0.8:1, 0.75:1, 0.7:1, 0.65:1, 0.6:1, and 0.55:1.
In accordance with certain embodiments of the invention, the step of depositing the plurality of cellulose pulp fibers onto the carded web or carded fabric comprises air-laying the plurality of cellulose pulp fibers onto the carded web or carded fabric. In accordance with certain embodiments of the invention, the layer of the plurality of cellulose pulp fibers may be directly impacted by the at least one fluid stream while the carded web or carded fabric may be positioned directly adjacent the 3D imaging device (e.g., imaging sleeve).
In another aspect, the present invention provides a wipe including a plant-based nonwoven fabric, such as those described and disclosed herein, a liquid additive disposed onto or within a first outer surface and/or a second outer surface of the plant-based nonwoven fabric. For example, the liquid additive may comprises 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 cleansing composition including one or more emulsifier, one or more detergents, one or more surfactants, one or more soaps, or any combination thereof.
In accordance with certain embodiments of the invention, the wipe may be disposed within a container. For example, the wipe may comprise a continuous material including a plurality of lines of perforation forming separation lines defining individual pieces or wipes. Alternatively, the wipe may comprise a plurality of individually separated pieces or wipes such that a person may simply grab a single individual wipe without the need of separating it from additional pieces or wipes.
The present disclosure is further illustrated by then following examples, which in no way should be construed as being limiting. That is, the specific features described in the following examples are merely illustrative and not limiting.
A 48.7 gsm plant-based nonwoven fabric was compared to a 61.2 paper wipe to illustrate the improved rebound associated with plant-based nonwoven fabrics in accordance with certain embodiments of the invention. The plant-based nonwoven fabric was formed from a 50% by weight of cellulose pulp and a 50% by weight of Lyocell staple fibers, in which the cellulose and Lyocell staple fibers were hydroentangled together to provide the plant-based nonwoven fabric. The hydroentangling operation was performed as follow: (i) pre-image entangling pressures in the direction of travel: 45, 65, 90, and 100 psi; and (ii) imaging pressures in the direction of travel: 55, 55, & 35 psi. The speed was 200 mpm (e.g., commercial line) and imaging energy was 0.0205 HP/Hr/Lb.
The loft rebound was measured using the TA Instrument's ARES-G2 rheometer. The rheometer was installed with a 25 mm parallel plate stainless steel geometry, and all the measurements were conducted at room temperature (23° C.+/−10C). A 30 mm×30 mm sample was placed between the parallel plates and the initial thickness was measured using 0.245 N force. Then, a compression force was applied for 30 sec and the thickness was recorded. Next, the force was removed and the sample relaxed. Later, again the thickness was measured using 0.245 N force to measure the recovery. The recovery was measured at three different compression forces (2 N, 3 N, and 4 N), and always a fresh sample was used. The final three columns of Table 1 (i.e., the three last columns to the right of Table 1) are normalized for the basis weight of the sample (e.g., respective % divided by the basis weight of the sample).
With regard to the data from Table 1, the plant-based nonwoven has a first loft rebound percentage based on the thickness before compression and the thickness after compression (e.g., the thickness in a relaxed state after removal of the load as a percentage of the thickness before compression expressed as (A/B)*100 from Table 1) as follows: for the 2 N force=95.5%; for the 3 N force=93.1%; and for the 4 N force=91.9%.
The plant-based nonwoven from above was also compared to 100% rayon nonwoven wipe under the same protocol discussed above. The data for this comparison under a 3 N load is summarized in Table 2, in which the last column of Table 2 is normalized for the basis weight of the sample (e.g., respective % divided by the basis weight of the sample).
The impact of the fluid pressure used for hydroentangling the plant-based nonwoven is illustrated in Table 3. In this regard, Sample 1 (i.e., identified as BB-2201 in Table 2) represents hydroentanglement at a “higher” fluid pressure striking the fibers of the material being consolidated, while Sample 2 (i.e., identified as BB-2110 in Table 2) represents hydroentanglement at a lower fluid pressure striking the fibers of the material being consolidated. In particular, for Sample 1, the pre-entangling pressures employed in the direction of travel was 45, 65, 90, and 100 psi, while the imaging pressure employed in the direction of travel was 55, 55 and 35 psi. As illustrated in Table 2, the use of a “lower” pressure for hydroentanglement imparts certain improved desirable physical properties. For example, the use of the lower hydroentanglement fluid pressure provided a noticeable increase in Dry Machine Direction Tension (MDT) and reduced Dry Machine Direction Elongation (MDE). Additionally, the lower hydroentanglement fluid pressure provided a statistically significant softer nonwoven fabric in the MD and the CD. For example, the use of the lower hydroentanglement fluid pressure provided 49.3% more Taber Abrasion Cycles Dry (smooth side) and 16.7% more Taber Abrasion Cycles Wet (smooth side).
These and other modifications and variations to the invention may be practiced by those of ordinary skill in the art without departing from the spirit and scope of the invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and it is not intended to limit the invention as further described in such appended claims. Therefore, the spirit and scope of the appended claims should not be limited to the exemplary description of the versions contained herein.
This application claims priority under 35 U.S.C. § 119 to U.S. Provisional Application No. 63/604,309 filed Nov. 30, 2023, which is expressly incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63604309 | Nov 2023 | US |
