Patent Application
20240344254
Embodiments of the presently-disclosed invention relate generally to nonwoven fabrics and composite nonwoven fabrics having a three-dimensional (3D) image imparted therein, in which the nonwoven fabrics and composite nonwoven fabrics include a plurality of meltblown fibers physically entangled together either alone or in combination with a plurality of cellulosic fibers, and/or a plurality of spunbond fibers.
Absorbent products, such as personal hygiene articles, require abrasion resistance and low linting in combination with good fluid handling characteristics (e.g., acquisition rate and rewet). Personal hygiene articles typically include a liner layer or topsheet positioned between the wearer and an absorbent core. The purpose of this liner is to provide a surface suitable for contact with the skin and to contain the absorbent materials. The liners should be permeable to bodily fluids and allow rapid absorption by the core, thereby taking fluid away from the skin of the wearer at a high rate. Additionally, the liners should be thick enough to prevent migration of the liquid from the absorbent core back to the skin of the wearer when the wearer applies pressure to the product (e.g., when sitting). However, the liners typically used in personal hygienic articles are often a thin spunbond fabric. The low thickness of these spunbond fabrics makes it difficult to achieve good rewet properties without the use of a high performance acquisition and distribution layer that is typically placed between the liner and the absorbent core.
Therefore there at least remains a need in the art for three-dimensional nonwoven fabrics that may provide desirable thickness and strength.
One or more embodiments of the invention may address one or more of the aforementioned problems. Certain embodiments according to the invention provide a nonwoven fabric including a plurality of meltblown fibers, such as for example BIAX-meltblown fibers, consolidated together via physical entanglement of the plurality of meltblown fibers. The nonwoven fabric may also include a three-dimensional (3D) image imparted therein.
In another aspect, certain embodiments according to the invention provide a composite nonwoven fabric including a first layer comprising a nonwoven fabric including a plurality of meltblown fibers, such as for example BIAX-meltblown fibers, and a second layer comprising a first meltspun nonwoven comprising a first plurality of spunbond fibers, in which the first plurality of spunbond fibers are physically entangled with the plurality of meltblown fibers. The composite nonwoven fabric includes a three-dimensional (3D) image imparted therein.
In another aspect, certain embodiments according to the invention provide a method of making a nonwoven fabric, such as those described and disclosed herein. The method may comprise (i) providing or forming a meltblown nonwoven web comprising a plurality of meltblown fibers, such as for example BIAX-meltblown fibers; and (ii) hydroentangling the plurality of meltblown fibers together to form the nonwoven fabric, in which hydroentangling the plurality of meltblown fibers together comprises applying at least one jet of fluid directly or indirectly onto the meltblown nonwoven web to consolidate the meltblown web and to impart a three-dimensional (3D) image into the nonwoven fabric.
In another aspect, certain embodiments according to the invention provide a method of making a composite nonwoven fabric (e.g., a hydroentangled nonwoven composite nonwoven fabric), such as those described and disclosed herein. The method may comprise: (i) providing or forming a composite nonwoven juxtaposed webs or composite nonwoven fabric comprising (a) a first layer comprising a nonwoven web or fabric including a plurality of meltblown fibers, such as for example BIAX-meltblown fibers, alone or in combination with a plurality of cellulosic fibers, and (b) a second layer comprising a first meltspun nonwoven web or fabric comprising a first plurality of spunbond fibers; and (ii) hydroentangling the plurality of first layer and the second layer together to form the composite nonwoven fabric, wherein hydroentangling the first layer and the second layer together comprises applying at least one jet of fluid directly or indirectly onto the first layer, the second layer, or both to consolidate the first layer and the second layer together and to impart a three-dimensional (3D) image into the composite 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. 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.
The presently-disclosed invention relates generally to nonwoven fabrics and composite nonwoven fabrics having a three-dimensional (3D) image imparted therein. The nonwoven fabrics and composite nonwoven fabrics include a plurality of meltblown fibers, such as for example BIAX-meltblown fibers, physically entangled together either alone or in combination with a plurality of cellulosic fibers, and/or a plurality of spunbond fibers. BIAX-meltblown fibers, for example, beneficially have a high degree of molecular orientation and tenacity in comparison to a traditional meltblown fiber formed from the same polymeric composition and having an identical size (e.g., diameter, length, etc.). BIAX-meltblown fibers if utilized, in accordance with certain embodiments of the invention, may be formed from a meltblown process that is intermediate between the conventional meltblown process and the conventional spunbond process. A description of this process and apparatus used is given in U.S. Pat. No. 6,013,223, which is incorporated herein in its entirety. In this regard, the process and apparatus used to form a plurality of BIAX-meltblown fibers utilizes pressurized hot air that is blown out of holes around each spinning nozzle at a high velocity parallel to the fibers being extruded. As this air expands, it cools quickly to solidify the fibers within a few millimeters from exiting the spinning nozzles, at the same time, the expanding air is exerting an accelerating force on the fibers away from the spinnerette and toward a draw jet. In this regard, the fiber flow may not depend on gravity; the process can be vertical, horizontal, or at any angle. Since the quench air is parallel to the fiber stream, high air velocities can be tolerated without rupturing the fibers, causing rapid cooling of the fibers. Interplay between hot air pressure and velocity may be needed to achieve a desirably high degree of molecular orientation. If no quench air is used, for example, the fibers solidify slowly and tend to stick together in bundles in the draw jet. If fibers are accelerated too much by the quench air, or the air temperature is too high, the draw jet exerts little drawing force on the fibers that resemble the traditional “meltblowing” process which causes little molecular orientation and therefore low strength fibers. In accordance with certain embodiments of the invention, BIAX-meltblown fibers may be achieved when the high velocity quench air accelerates the fibers somewhat, but mainly cools and solidifies the fibers, and the draw jet, using cold air, provides the majority of the fiber attenuation. In accordance with certain embodiments of the invention, the nonwoven fabrics and composite nonwoven fabrics may be devoid of thermoplastic staple fibers (e.g., carded webs of staple fibers). In this regard, nonwoven fabrics and composite nonwoven fabrics that incorporated thermoplastic staple fibers (e.g., carded webs of staple fibers) may be re-created in accordance with certain embodiments of the invention in which the thermoplastic staple fibers are replaced with the plurality of meltblown fibers, such as for example BIAX-meltblown fibers.
Merely for purposes of illustrating differences between traditional meltblown nonwovens and BIAX-meltblown nonwovens, Table 1, which is provided below, shows a comparison of the materials and typical process conditions used to make conventional polypropylene meltblown, polypropylene spunbond, and BIAX polypropylene meltblown fibers.
Table 2, which is provided below, shows a comparison of the properties of polypropylene nonwoven webs made by the conventional meltblown process, and by the BIAX meltblown process.
Tear, MD (mN)
Tear, MD (mN)
)
)
)
)
)
indicates data missing or illegible when filed
As shown in FIG. 2, for instance, BIAX-meltblown nonwovens having about the same basis weights as those of conventional meltblown nonwovens may exhibit a geometric mean dry tensile strength, for example, at least twice that of the conventional meltblown webs. The geometric mean wet tensile strength index may be about three times that of the conventional meltblown webs of a similar basis weight. Wet and dry MD and CD toughness, and wet and dry MD tear strength are all substantially improved in the case of the BIAX-meltblown nonwovens. Wet thickness and bulk are broadly similar for both types of meltblown web. The average fiber diameter of the BIAX-meltblown nonwovens may be lower than that of the conventional meltblown web, which is also reflected in the relative air permeabilities.
The terms “substantial” or “substantially” may encompass the whole amount as specified, according to certain embodiments of the invention, or largely but not the whole amount specified (e.g., 95%, 96%, 97%, 98%, or 99% of the whole amount specified) according to other embodiments of the invention.
The terms “polymer” or “polymeric”, as used interchangeably herein, may comprise homopolymers, copolymers, such as, for example, block, graft, random, and alternating copolymers, terpolymers, etc., and blends and modifications thereof. Furthermore, unless otherwise specifically limited, the term “polymer” or “polymeric” shall include all possible structural isomers; stereoisomers including, without limitation, geometric isomers, optical isomers or enantionmers; and/or any chiral molecular configuration of such polymer or polymeric material. These configurations include, but are not limited to, isotactic, syndiotactic, and atactic configurations of such polymer or polymeric material. The term “polymer” or “polymeric” shall also include polymers made from various catalyst systems including, without limitation, the Ziegler-Natta catalyst system and the metallocene/single-site catalyst system. The term “polymer” or “polymeric” shall also include, in according to certain embodiments of the invention, polymers produced by fermentation process or biosourced.
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. Cellulose 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.
The terms “nonwoven” and “nonwoven web”, as used herein, may comprise a web having a structure of individual fibers, filaments, 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 “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.
As used herein, “meltspun” or “melt-spun” generally refers to fiber forming processes of spunbonding or melt-blowing.
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 SPINLACER. Spunbond fibers, for example, comprise 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 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 “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.
As used herein, the term “BIAX-meltblown fibers” shall mean meltblown filaments or fibers made by a meltblown process that is intermediate between the conventional meltblown process and the conventional spunbond process. A description of the process and apparatus used is given in U.S. Pat. No. 6,013,223, which is incorporated herein in its entirety. In the BIAX-meltblown process, a polymer grade(s) with a relatively high average molecular weight (similar to the polymer grade(s) used in the spunbond process) is used versus the lower average molecular weight polymer grade(s), with a higher melt flow rate, normally used in the production of conventional meltblown filaments. Use of such a polymer grade(s) with a relatively high average molecular weight generally produces meltblown filaments with a higher tenacity. The BIAX-meltblown process generally may comprise extruding thermoplastic polymers through spinning nozzles arranged in multiple rows to form molten fibers that are accelerated by expanding hot gas flowing parallel to the extrusion nozzles and the fibers to a first velocity, then cooled below their melting point, and subsequently accelerated to a higher velocity by an air jet fed with compressed cold air. The resulting BIAX-meltblown fibers have a high degree of molecular orientation and tenacity. In this regard, a nonwoven fabric may be formed entirely or at least in part from a plurality of BIAX-meltblown fibers, in which the nonwoven fabric is stronger as made than a nonwoven fabric of the same basis weight and of the same polymer made by the conventional meltblown process, and consolidated in the identical manner.
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.
Certain embodiments according to the invention provide a nonwoven fabric including a plurality of meltblown fibers, such as for example BIAX-meltblown fibers, consolidated together via physical entanglement (e.g., hydroentangled) of the plurality of meltblown fibers. The nonwoven fabric may also include a three-dimensional (3D) image imparted therein. In accordance with certain embodiments of the invention, the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, may have an average diameter from about 5 to about 15 microns, such as at least about any of the following: 5, 6, 7, and 8 microns, and/or at most about any of the following: 15, 14, 13, 12, 11, 10, 9, and 8 microns. Additionally or alternatively, the plurality of meltblown fibers may be continuous in length
In accordance with certain embodiments of the invention, the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, may comprise a polymer component and optionally an additive component, in which the polymer component may comprise at least one polyolefin, such as a polypropylene, a propylene-containing copolymer, a polyethylene, an ethylene-containing copolymer, or any combinations thereof. The polymer component, for example, may comprise from about 50% to 100% by weight of the at least one polyolefin, such as at least about any of the following: 50, 60, 70, and 75% by weight, and/or at most about any of the following: 100, 98, 95, 90, 85, 80, and 75% by weight. Additionally or alternatively, the polymer component may comprise at least one polyester, such as a polyethylene terephthalate. For example, the polymer component comprises from about 50% to 100% by weight of the at least one polyester, such as at least about any of the following: 50, 60, 70, and 75% by weight, and/or at most about any of the following: 100, 98, 95, 90, 85, 80, and 75% by weight.
In accordance with certain embodiments of the invention, the nonwoven fabric may further comprise a plurality of cellulosic fibers physically entangled with the plurality of meltblown fibers, such as for example BIAX-meltblown fibers. The plurality of cellulosic fibers, as noted above, may comprise natural cellulose, synthetic cellulose, such as a regenerated cellulose, or a combination thereof. The plurality of meltblown fibers, such as for example BIAX-meltblown fibers, may comprise from about 30% to 100% by weight of a total fiber weight of the nonwoven fabric, such as at least about any of the following: 30, 35, 40, 45, 50, 55, and 60% by weight of a total fiber weight of the nonwoven fabric, and/or at most about any of the following: 100, 98, 95, 90, 85, 80, 75, 70, 65, and 60% by weight of a total fiber weight of the nonwoven fabric. Additionally or alternatively, the plurality of cellulosic fibers may comprise from about 0% to 70% by weight of a total fiber weight of the nonwoven fabric, such as at least about any of the following: 0, 10, 20, 30, 40, and 50% by weight of a total fiber weight of the nonwoven fabric, and/or at most about any of the following: 70, 65, 60, 55, and 50% by weight of a total fiber weight of the nonwoven fabric.
In accordance with certain embodiments of the invention, a least a portion of the plurality of cellulosic fibers, if present, may be partially embedded into a portion of the plurality of meltblown fibers, such as for example BIAX-meltblown fibers. For example, the plurality of cellulosic fibers may to injected into the meltblown fibers, such as for example BIAX-meltblown fibers, during laydown and a portion of the plurality of cellulosic fibers may impact the meltblown fibers at a location from the die in which the meltblown fibers are still at least partially in a semi-molten state. As such, a portion of the plurality of cellulosic fibers may impact and partially embed within and/or become agglutinated with the semi-molten meltblown fibers, such as for example BIAX-meltblown fibers, prior to substantial and/or total solidification.
In accordance with certain embodiments of the invention, the nonwoven fabric may be devoid of any additional layers, such as any additional layers that do not include meltblown fibers, such as for example BIAX-meltblown fibers, meltspun layers, or carded layers. In this regard, certain embodiments of the invention provide a single layer nonwoven fabric, which may be utilized in a variety of applications.
In accordance with certain embodiments of the invention, the 3D image comprises a 3D pattern on at least a first side of the nonwoven fabric (and usually on both outer sides of the nonwoven fabric) and includes a plurality of recessed portions in a z-direction relative to an imaginary central plane extending through the 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 nonwoven fabric (and usually on both outer sides of the nonwoven fabric) and includes a plurality of elevated portions in a z-direction relative to an imaginary central plane extending through the 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 accordance with certain embodiments of the invention, the nonwoven fabric may further comprise one or more apertures extending completely through the nonwoven fabric. The one or more apertures, for example, may define an open area of the nonwoven fabric, the open area comprising from about 1% to about 30%, such as at least about any of the following: 1, 2, 3, 5, 6, 8, 10, 12, 14, and 15%, and/or at most about any of the following: 30, 28, 26, 25, 24, 22, 20, 18, 16, and 15%. In accordance with certain embodiments of the invention, the one or more apertures may have an average diameter from about 0.1 mm to about 3 mm, such as at least about any of the following: 0.1, 0.2, 0.4, 0.5, 0.6, 0.8, and 1 mm, and/or at most about any of the following: 3, 2.5, 2, 1.8, 1.6, 1.5, 1.4, 1.2, and 1 mm. The one or more apertures may comprise one or more different shapes, such as circular and/or non-circular apertures, such as squares, rectangles, ellipses, and polygons, wherein the average diameter is the longest dimension across the aperture.
In accordance with certain embodiments of the invention, at least 50% by number of the one or more apertures, if present, may be located within the plurality of recessed portions, such as at least about any of the following: 50, 55, 60, 65, 70, and 75% by number, and/or at most about any of the following: 100, 95, 90, 85, 80, and 75% by number.
In accordance with certain embodiments of the invention, the additive component may comprise one or more fillers (e.g., calcium carbonate particles or the like), one or more surfactants (e.g., hydrophilic surfactants to render the meltblown fibers, such as for example BIAX-meltblown fibers, hydrophilic or wettable), one or more slip additives, or any combinations thereof. The additive component, for example, may comprise one or more hydrophilic surfactant dispersed throughout respective bodies of the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, and/or topically applied to the respective exterior surfaces of the plurality of meltblown fibers, such as for example BIAX-meltblown fibers. Additionally or alternatively, the additive component comprises one or more slip agents dispersed throughout respective bodies of the plurality of meltblown fibers, such as for example BIAX-meltblown fibers and/or topically applied to the respective exterior surfaces of the plurality of meltblown fibers, such as for example BIAX-meltblown fibers; wherein the one or more slip agents comprises an amide, such as one or more primary amides comprising erucamide, oleamide, strearamide, behenamide, or any combination thereof. Additionally or alternatively, the slip agent may comprise one or more bis-amide comprising an ethylene bis-amide.
In accordance with certain embodiments of the invention, the slip agent comprises one or more amides, in which the one or more amides comprises an unsaturated aliphatic chain, a saturated aliphatic chain, or a combination thereof. In accordance with certain embodiments of the invention, the one or more aliphatic chains may each independently comprise from about 1 to about 30 carbon atoms (e.g., about 5 to about 30 carbon atoms). For example, a secondary amides and bis-amides may comprise two saturated and/or unsaturated carbon chains the may each independently comprise from about 1 to about 30 carbon atoms (e.g., about 5 to about 30 carbon atoms). By way of example only, the one or more aliphatic chains may each independently comprise from at least about any of the following: 1, 5, 10, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, and 25 carbon atoms and/or at most about 30, 29, 28, 27, 26, 25, 20, and 15 carbon atoms (e.g., about 15 to about 25 carbon atoms, about 20 to 30 carbon atoms, etc.). In accordance with certain embodiments of the invention, the slip agent may comprise an amide including an unsaturated aliphatic chain having one or more elements or unsaturation. An element of unsaturation corresponds to two fewer hydrogen atoms than in the saturated formula. For example, a single double bound accounts for one element of unsaturation, while a triple bond would account for two elements of unsaturation. In accordance with certain embodiments of the invention, the slip agent includes an unsaturated aliphatic chain comprising from about 1 to about 10 elements of unsaturation (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 elements of saturation).
In accordance with certain embodiments of the invention, the slip agent may comprise a combination of a greater amount of, for example, stearamide and a lesser amount of, for example, erucamide. For example, the combination of the greater amount of stearamide and the lesser amount of erucamide may comprise from about 25 to about 40 weight percent erucamide and from about 60 to about 75 weight percent stearamide.
In accordance with certain embodiments of the invention, the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, may comprise from 0 to about 5 wt. % of the slip agent, such as at least about any of the following: 0, 0.2, 0.4, 0.5, 0.6, 0.8, 1, 1.2, 1.4, 1.5, 1.6, 1.8, and 2 wt. %, and/or at most about any of the following: 5, 4.8, 4.5, 4.2, 4, 3.8, 3.5, 3.2, 3, 2.8, 2.5, 2.2, and 2 wt. %.
In accordance with certain embodiments of the invention, the nonwoven fabric may comprise a basis weight from about 5 to about 100 grams-per-square-meter (gsm), such as at least about any of the following: 5, 8, 10, 15, 20, 30, 40, and 50 gsm, and/or at most about any of the following: 100, 90, 80, 70, 60, and 50 gsm.
In another aspect, certain embodiments according to the invention provide a composite nonwoven fabric including a first layer comprising a nonwoven fabric including a plurality of meltblown fibers, such as for example BIAX-meltblown fibers (e.g., alone or in combination with a plurality of cellulosic fibers as noted above), and a second layer comprising a first meltspun nonwoven comprising a first plurality of spunbond fibers, in which the first plurality of spunbond fibers are physically entangled (e.g., hydroentangled) with the plurality of meltblown fibers, such as for example BIAX-meltblown fibers. The composite nonwoven fabric includes a three-dimensional (3D) image imparted therein. In accordance with certain embodiments of the invention, the first layer may comprise any of the nonwoven fabrics discussed and disclosed herein. For example, the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, may have an average diameter from about 5 to about 15 microns, such as at least about any of the following: 5, 6, 7, and 8 microns, and/or at most about any of the following: 15, 14, 13, 12, 11, 10, 9, and 8 microns. Additionally or alternatively, the plurality of meltblown fibers, such as for example BIAX-meltblown fibers may be continuous in length. As noted above, the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, may comprise a polymer component and optionally an additive component, in which the polymer component may comprise at least one polyolefin, such as a polypropylene, a propylene-containing copolymer, a polyethylene, an ethylene-containing copolymer, or any combinations thereof. The polymer component, for example, may comprise from about 50% to 100% by weight of the at least one polyolefin, such as at least about any of the following: 50, 60, 70, and 75% by weight, and/or at most about any of the following: 100, 98, 95, 90, 85, 80, and 75% by weight. Additionally or alternatively, the polymer component may comprise at least one polyester, such as a polyethylene terephthalate. For example, the polymer component comprises from about 50% to 100% by weight of the at least one polyester, such as at least about any of the following: 50, 60, 70, and 75% by weight, and/or at most about any of the following: 100, 98, 95, 90, 85, 80, and 75% by weight.
In accordance with certain embodiments of the invention, the composite nonwoven fabric may further comprise a third layer comprising a second meltspun nonwoven comprising a second plurality of spunbond fibers, in which the second plurality of spunbond fibers are physically entangled with the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, the first plurality of spunbond fibers, or both. In accordance with certain embodiments of the invention, the first meltspun nonwoven and the second nonwoven define exterior surfaces of the composite nonwoven fabric, while the meltblown fibers, such as for example BIAX-meltblown fibers, are predominantly located at an interior portion of the composite nonwoven fabric.
In accordance with certain embodiments of the invention, the first meltspun nonwoven and the second meltspun nonwoven independently from each other may comprise a spunbond-meltblown-spunbond (SMS) structure. Alternatively, the first meltspun nonwoven and the second meltspun nonwoven independently from each other may comprise predominately spunbond fibers, such as at least about 60% to 100% by weight of spunbond fibers or such as at least about any of the following: 60, 70, and 75% by weight, and/or at most about any of the following: 100, 90, 80, and 75% by weight.
The first meltspun nonwoven and the second meltspun nonwoven independently from each other may comprise a basis weight from about 5 to about 50 gsm, such as at least about any of the following: 5, 8, 10, 12, 15, and 20 gsm, and/or at most about any of the following: 50, 40, 30, 25, and 20 gsm.
In accordance with certain embodiments of the invention, the 3D image comprises a 3D pattern on at least a first side of the composite nonwoven fabric (and usually on both outer sides of the composite nonwoven fabric) and includes a plurality of recessed 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. Additionally or alternatively, the 3D image comprises a 3D pattern on a first side of the composite 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 accordance with certain embodiments of the invention, the composite nonwoven fabric may further comprise one or more apertures extending completely through the composite nonwoven fabric. The one or more apertures, for example, may define an open area of the composite nonwoven fabric, the open area comprising from about 1% to about 30%, such as at least about any of the following: 1, 2, 3, 5, 6, 8, 10, 12, 14, and 15%, and/or at most about any of the following: 30, 28, 26, 25, 24, 22, 20, 18, 16, and 15%. In accordance with certain embodiments of the invention, the one or more apertures may have an average diameter from about 0.1 mm to about 3 mm, such as at least about any of the following: 0.1, 0.2, 0.4, 0.5, 0.6, 0.8, and 1 mm, and/or at most about any of the following: 3, 2.5, 2, 1.8, 1.6, 1.5, 1.4, 1.2, and 1 mm. The one or more apertures may comprise one or more different shapes, such as circular and/or non-circular apertures, such as squares, rectangles, ellipses, and polygons, wherein the average diameter is the longest dimension across the aperture.
In accordance with certain embodiments of the invention, at least 50% by number of the one or more apertures, if present, may be located within the plurality of recessed portions, such as at least about any of the following: 50, 55, 60, 65, 70, and 75% by number, and/or at most about any of the following: 100, 95, 90, 85, 80, and 75% by number.
In accordance with certain embodiments of the invention, the composite nonwoven fabric may comprise a basis weight from about 15 to about 200 grams-per-square-meter (gsm), such as at least about any of the following: 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, and 100 gsm, and/or at most about any of the following: 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, and 100 gsm.
Certain embodiments of the invention also provide an article comprising a nonwoven fabric or a composite nonwoven fabric, such as those described and disclosed herein, wherein the article comprises a hygiene article, such as a diaper or feminine-hygiene product, or a wipe, such as a dry wipe or a wet wipe loaded with a cleaning composition and/or an antimicrobial agent and/or a lotion.
In another aspect, certain embodiments according to the invention provide a method of making a nonwoven fabric, such as those described and disclosed herein. The method may comprise (i) providing or forming a meltblown nonwoven web comprising a plurality of meltblown fibers, such as for example BIAX-meltblown fibers; and (ii) hydroentangling the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, together to form the nonwoven fabric, in which hydroentangling the plurality of meltblown fibers, such as for example BIAX-meltblown fibers, together comprises applying at least one jet of fluid directly or indirectly onto the meltblown nonwoven web to consolidate the meltblown web and to impart a three-dimensional (3D) image into the nonwoven fabric.
In accordance with certain embodiments of the invention, the method may further comprise a first consolidation step to form an intermediate nonwoven fabric (e.g., a precursor material) prior to imparting the 3D image into the nonwoven fabric. The first consolidation step, for example, may comprises a light hydroentanglement operation to stabilize the meltblown nonwoven web, in which a first fluid pressure of the light hydroentanglement operation is less than a second fluid pressure associated with imparting the 3D image into the nonwoven fabric.
In accordance with certain embodiments of the invention, the method may further comprise a step of providing a 3D image transfer sleeve having a movable imaging surface comprising a 3D dimensional pattern etched therein, and advancing the meltblown nonwoven web or the intermediate nonwoven fabric onto the image transfer sleeve so the meltblown nonwoven web or the intermediate nonwoven fabric moves with the imaging surface, and applying the least one jet of fluid directly or indirectly onto the meltblown nonwoven web or the intermediate nonwoven fabric to form the 3D image.
In another aspect, certain embodiments according to the invention provide a method of making a composite nonwoven fabric (e.g., a hydroentangled composite nonwoven fabric), such as those described and disclosed herein. The method may comprise: (i) providing or forming a composite nonwoven juxtaposed webs or composite nonwoven fabric comprising (a) a first layer comprising a nonwoven web or fabric including a plurality of meltblown fibers, such as for example BIAX-meltblown fibers, alone or in combination with a plurality of cellulosic fibers, and (b) a second layer comprising a first meltspun nonwoven web or fabric comprising a first plurality of spunbond fibers; and (ii) hydroentangling the plurality of first layer and the second layer together to form the hydroentangled composite nonwoven fabric, wherein hydroentangling the first layer and the second layer together comprises applying at least one jet of fluid directly or indirectly onto the first layer, the second layer, or both to consolidate the first layer and the second layer together and to impart a three-dimensional (3D) image into the composite nonwoven fabric.
The method, in accordance with certain embodiments of the invention, may further comprise a first consolidation step bonding the first layer and the second layer together to form an intermediate composite nonwoven fabric prior to imparting the 3D image into the composite nonwoven fabric. The first consolidation step may comprise a light hydroentanglement operation to lightly integrate the first layer and the second layer together, in which a first fluid pressure of the light hydroentanglement operation is less than a second fluid pressure associated with imparting the 3D image into the nonwoven fabric.
In accordance with certain embodiments of the invention, the method may further comprise a step of providing a 3D image transfer sleeve having a movable imaging surface comprising a 3D dimensional pattern etched therein, and advancing the composite nonwoven juxtaposed webs or composite nonwoven fabric onto the image transfer sleeve so the composite nonwoven juxtaposed webs or composite nonwoven fabric moves with the imaging surface, and applying the least one jet of fluid directly or indirectly onto the composite nonwoven juxtaposed webs or composite nonwoven fabric to form the 3D image.
In accordance with certain embodiments of the invention, suitable three-dimensional imaging devices may comprise imaging sleeves include those described, for example, in U.S. Pat. Nos. RE38,105 and RE38,505, in which the contents of both are hereby incorporated by reference in their entirety. For example, the nonwoven fabric and the composite nonwoven fabric may include a three-dimensional image formed therein that may be formed throughout the nonwoven fabric or composite 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 and 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.
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.
| Number | Date | Country | |
|---|---|---|---|
| 63459428 | Apr 2023 | US |
