WO2024229061A2 - Methods of converting assets to increase cellulosic yarn production - Google Patents
Methods of converting assets to increase cellulosic yarn production Download PDFInfo
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- WO2024229061A2 WO2024229061A2 PCT/US2024/027130 US2024027130W WO2024229061A2 WO 2024229061 A2 WO2024229061 A2 WO 2024229061A2 US 2024027130 W US2024027130 W US 2024027130W WO 2024229061 A2 WO2024229061 A2 WO 2024229061A2
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- yarn
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- winding
- filaments
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H54/00—Winding, coiling, or depositing filamentary material
- B65H54/02—Winding and traversing material on to reels, bobbins, tubes, or like package cores or formers
- B65H54/10—Winding and traversing material on to reels, bobbins, tubes, or like package cores or formers for making packages of specified shapes or on specified types of bobbins, tubes, cores, or formers
- B65H54/20—Winding and traversing material on to reels, bobbins, tubes, or like package cores or formers for making packages of specified shapes or on specified types of bobbins, tubes, cores, or formers forming multiple packages
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- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
- D01F2/24—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives
- D01F2/28—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives from organic cellulose esters or ethers, e.g. cellulose acetate
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- D—TEXTILES; PAPER
- D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
- D02J—FINISHING OR DRESSING OF FILAMENTS, YARNS, THREADS, CORDS, ROPES OR THE LIKE
- D02J1/00—Modifying the structure or properties resulting from a particular structure; Modifying, retaining, or restoring the physical form or cross-sectional shape, e.g. by use of dies or squeeze rollers
- D02J1/08—Interlacing constituent filaments without breakage thereof, e.g. by use of turbulent air streams
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2701/00—Handled material; Storage means
- B65H2701/30—Handled filamentary material
- B65H2701/31—Textiles threads or artificial strands of filaments
- B65H2701/313—Synthetic polymer threads
- B65H2701/3132—Synthetic polymer threads extruded from spinnerets
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/04—Dry spinning methods
Definitions
- Textile fabrics consisting of yarns are widely used in a variety of applications. These fabrics may be formed by weaving, knitting, crocheting, knotting, or felting yarn made of materials, such as, for example, polyesters, polyamides, acrylics, polyurethanes, glass, polypropylene, silk, and a variety of cellulosic materials. Cellulose acetate fibers are one type of cellulosic material known for their sustainability, biodegradability, and renewability.
- cellulose acetate fibers are formed by extruding dope from a spinneret to produce multiple filaments, which may then be joined to create multi-filament yarns.
- the possibility of increasing fiber production has been explored as the market for cellulose-based textiles has grown.
- adding additional spinning machines to a production facility or additional winders to an existing spinning machine is a time- consuming and expensive endeavor.
- SUMMARY [0003] Provided herein is a method of producing cellulosic yarn.
- the method comprises spinning a plurality of cellulosic filaments into a cabinet at greater than about 300 denier per cabinet, and separating the plurality of cellulosic filaments into a plurality of groups of filaments.
- a method of producing acetate yarn comprises providing an acetate tow production facility comprising a dope forming system, a spinning system, a tow band forming system, a tow band crimping system, and a tow band baling system.
- the method also comprises converting the acetate tow production facility into an acetate yarn production facility, wherein the converting comprises installing a yarn winding system downstream of the spinning system, and producing packages of acetate yarn using the acetate yarn production facility.
- the producing comprises forming a cellulose acetate dope using the dope forming system, spinning cellulose acetate filaments from the cellulose acetate dope using the spinning system, and winding the cellulose acetate filaments using the yarn winding system to produce the packages of acetate yarn.
- At least one of the tow band forming system, the tow band crimping system, or the tow band baling system is not utilized during the producing step.
- a method of producing acetate yarn comprises providing an acetate tow production facility comprising a dope forming system, a dope pump, a spinning system, a solvent recovery system, a finish application system, an entanglement system, and a yarn winding system.
- the method also comprises producing packages of acetate yarn using the acetate tow production facility.
- the producing comprises forming a cellulose acetate dope using the dope forming system, pumping cellulose acetate dope from the dope forming system to the spinning system using the dope pump, spinning cellulose acetate filaments using the spinning system, recovering solvent evaporated from the filaments using the solvent recovery system, applying a finish to the cellulose acetate filaments using the finish application system, individually-entangling groups of the filaments using the entanglement system to produce a plurality of individually-entangled cellulose acetate yarns, and winding the individually-entangled cellulose acetate yarns using the yarn winding system to produce packages of cellulose acetate yarn.
- FIG. 1 is a schematic illustration of an example yarn production system.
- FIG. 2 illustrates one example of the yarn guide and winding sub- assemblies shown in FIG.1.
- FIG.3 is a side view illustration of an example yarn package that may be produced as shown in FIG.2.
- FIG. 3A is a side view illustration of an example yarn package that may be produced as shown in FIG.2.
- FIG.4 is a side view illustration of another example yarn package that may be produced as shown in FIG.2.
- FIG.4A is a side view illustration of another example yarn package that may be produced as shown in FIG.2.
- FIG.5 illustrates another example of the yarn guide and winding sub- assemblies shown in FIG.1.
- FIG.6 is a side view illustration of an example yarn package that may be produced as shown in FIG.5.
- FIG. 6A is a side view illustration of an example yarn package that may be produced as shown in FIG.5.
- FIG.7 illustrates another example of the yarn guide and winding sub- assemblies shown in FIG.1.
- FIG.8 is a side view illustration of an example yarn package that may be produced as shown in FIG.7.
- FIG.9 illustrates another example of the yarn guide and winding sub- assemblies shown in FIG.1.
- FIG. 10 is a side view illustration of an example yarn package that may be produced as shown in FIG.9.
- FIG.10A is a side view illustration of an example yarn package that may be produced as shown in FIG.9.
- FIG.11 is a schematic illustration of an example portion of the yarn production system shown in FIG.1.
- FIG.12 is a schematic illustration of another example portion of the yarn production system shown in FIG.1.
- FIG.13 is a schematic illustration of another example portion of the yarn production system shown in FIG.1.
- FIG. 14 is a schematic illustration of an example yarn rewinding system.
- FIG.15 illustrates an example of the yarn rewinding system shown in FIG.14 performing side withdrawal.
- FIG. 16 illustrates another example of the yarn rewinding system shown in FIG.14 performing side withdrawal.
- FIG. 17 illustrates an example flow diagram of the yarn rewinding system shown in FIG.14 performing over-end withdrawal.
- FIG.18 is a schematic illustration of the yarn rewinding system shown in FIG.14 performing over-end withdrawal.
- FIG.19 illustrates another example flow diagram of the yarn rewinding system shown in FIG.14 performing over-end withdrawal.
- FIG. 20 illustrates an example of a conversion of an acetate tow production system to an acetate yarn production system.
- FIG.21 illustrates another example of a conversion of an acetate tow production system to an acetate yarn production system.
- FIG.22 illustrates another example of a conversion of an acetate tow production system to an acetate s3yarn production system.
- FIG.23 illustrates an example of a separation channel (344).
- DETAILED DESCRIPTION [0033] The present application generally relates to systems and methods for use in increasing cellulosic yarn production, and yarn packages produced therefrom. Yarn production is increased by expanding the production capabilities of existing fiber spinning machines and/or by converting other assets (e.g., tow production assets) to yarn production assets.
- assets e.g., tow production assets
- Such yarns can be utilized in expanded application opportunities in downstream fiber converting and end use apparel applications, for example.
- the yarns can be produced by any type of dry or wet spinning processes known in the art.
- wet spinning is defined as a process whereby at least one polymer is dissolved in at least one solvent to create a liquid solution. The solution is forced through a spinneret, and then comes into contact with a coagulating bath, which causes the liquid to solidify into fibers.
- dry spinning is defined as a process whereby at least one polymer is dissolved in at least one solvent and then extruded. As fibers emerge through the spinneret, the solvent is evaporated.
- Fiber spinning machines often include multiple spinnerets per cabinet, and the spinnerets each produce a yarn end that is then wound onto its own distinct core.
- the various sub-assemblies i.e., spinning, finish application, entanglement, yarn guide, and/or winding
- the spinning sub- assembly may be modified to increase the output of yarn ends from the production system. This may be accomplished by installing additional spinnerets near the top of an existing filament receiving section (e.g., a cabinet or liquid bath), or by modifying existing spinnerets to output more than one distinct filament grouping that each produces an individually-entangled yarn therefrom.
- the number of finish applicators, entanglers, yarn guides, and/or winding cores may be increased based on the increased number of yarns produced to accommodate the enhanced production capacity.
- the produced yarns are wound around at least one core on an existing common spool of the production system.
- the yarns may be wound in a winding configuration that enables the respective yarn ends to be unwindable from the core individually.
- the winding capacity of the existing spinning machine is increased without having to modify the winding system, such as by increasing the number of spools, to accommodate the additional cores needed to receive any additional yarn ends.
- the yarn package configurations, and methods of production and processing thereof, disclosed herein enable yarn output to be increased on a per cabinet basis while still producing a package of distinct yarn ends that are easily separable from one another when being unwound from the common core.
- the increased yarn output is based on increased yarn production capacity, rather than an increased yarn production rate and/or speed.
- the yarn production systems described herein may operate at the same production speed or a slower production speed than the existing asset from which is was modified, for example.
- the yarn packages disclosed herein also provide enhanced versatility to meet customer needs for varying package sizes and configurations.
- the fibers, filaments, and/or yarns as described herein may be formed from one or more cellulose esters including, but not limited to, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate formate, cellulose acetate propionate, cellulose acetate butyrate, cellulose propionate butyrate, and mixtures thereof.
- cellulose acetate Although described herein with reference to “cellulose acetate,” it should be understood that one or more of the above cellulose acid esters or mixed esters may also be used to form the fibers, nonwovens, and articles as described herein.
- Various types of cellulose esters are described, for example, in U.S. Patent Nos.1,698,049; 1,683,347; 1,880,808; 1,880,560; 1,984,147, 2,129,052; and 3,617,201, each of which is incorporated herein by reference to the extent not inconsistent with the present disclosure.
- other types of treated or regenerated cellulose may or may not be used in forming fibers as described herein.
- other types of recycle content material may or may not be used in forming fibers as described herein.
- Example recycle content material includes, but is not limited to, woven, knitted, or non-woven fabrics, thread, yarns, fiber fills, and various other plastic articles.
- the cellulose acetate (or other cellulose ester) useful in embodiments of the present invention can have a degree of substitution in the range between 2.2 and 3, between 2.25 and 2.9, between 2.35 and 8, or between 2.4 and 2.7.
- degree of substitution or “DS” refers to the average number of acetyl substituents per anhydroglucose ring of the cellulose polymer, wherein the maximum degree of substitution is 3.0.
- the cellulose acetate used to form fibers as described herein may have an average degree of substitution of at least about 1.95, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, or 2.3 and/or not more than about 2.9, 2.85, 2.8, 2.75, 2.7, 2.65, 2.6, 2.55, 2.5, 2.45, 2.4, or 2.35, with greater than 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99 percent of the cellulose acetate having a degree of substitution greater than 2.15, 2.2, or 2.25.
- greater than 90 percent of the cellulose acetate can have a degree of substitution greater than 2.2, 2.25, 2.3, or 2.35.
- the cellulose acetate may have a weight-average molecular weight (Mw) of not more than 90,000, measured using gel permeation chromatography with N-methyl-2-pyrrolidone (NMP) as the solvent.
- Mw weight-average molecular weight
- NMP N-methyl-2-pyrrolidone
- the cellulose acetate may have a molecular weight of at least about 10,000, at least about 20,000, 25,000, 30,000, 35,000, 40,000, or 45,000 and/or not more than about 90,000, 85,000, 80,000, 75,000, 70,000, 65,000, 60,000, or 50,000, and/or between 10,000 and 90,000, between 20,000 and 80,000, between 30,000 and 70,000, or between 40,000 and 60,000.
- FIG.1 is a schematic illustration of an example yarn production system 100.
- the cellulose acetate or other cellulose ester used in the production of the fibers and/or yarns described herein may be formed by any suitable method known in the art.
- cellulose acetate may be formed by reacting a cellulosic material such as wood pulp with acetic anhydride and a catalyst in an acidic reaction medium to form a cellulose acetate flake.
- the cellulose acetate or other cellulose ester used in the production of the fibers and/or yarns described herein may be formed by any suitable method, such as wet spinning, dry spinning, or melt spinning.
- the flake may then be dissolved in a solvent to form a “dope” solution which can be filtered and sent through at least one spinneret 102, as shown in FIG.1, to form continuous cellulose acetate filaments or fibers 103.
- a solvent for example, up to about 1 weight percent or more of titanium dioxide or other delusterant may be added to the dope prior to filtration, depending on the desired properties and ultimate end use of the fibers.
- Example solvents include, but are not limited to, acetone, methyl ethyl ketone, methylene chloride, dimethylformamide (DMF), dimethylacetamide (DMAC), dimethyl sulfoxide (DMSO), and combinations thereof.
- the solvent dope or flake used to form the cellulose acetate fibers may include few or no additives in addition to the cellulose acetate.
- additives can include, but are not limited to, pigments, colorants, antimicrobials, UV stabilizers, flame retardants, antioxidants, thermal stabilizers, pro-oxidants, acid scavengers, inorganics, photodegradation agents, biodegradation agents, decomposition accelerating agents, polyesters, enzymes, microorganisms, water soluble polymers, modified cellulose acetate, water-dispersible additives, nitrogen-containing compounds, hydroxy- functional compounds, oxygen-containing heterocyclic compounds, sulfur- containing heterocyclic compounds, anhydrides, and monoepoxides, or combinations thereof.
- the cellulose acetate fibers as described herein can include at least about 90, 90.5, 91, 91.5, 92, 92.5, 93, 93.5, 94, 94.5, 95, 95.5, 96, 96.5, 97, 97.5, 98, 98.5, 99, 99.5, 99.9, 99.99, 99.995, or 99.999 percent cellulose acetate, based on the total weight of the fiber.
- Fibers formed according to the present invention may include not more than about 10, 9.5, 9, 8.5, 8, 7.5, 7, 6.5, 6, 5.5, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5, 0.1, 0.01, 0.005, or 0.001 weight percent of additives other than cellulose acetate, including the specific additives listed herein.
- Cellulose acetate fibers can achieve higher levels of biodegradability and/or compostability without use of additives that have traditionally been used to facilitate environmental non-persistence of similar fibers.
- additives can include, for example, photodegradation agents, biodegradation agents, decomposition accelerating agents, and various types of other additives.
- the cellulose acetate fibers and articles produced therefrom have unexpectedly been found to exhibit enhanced biodegradability and compostability when tested under industrial, home, and/or soil conditions.
- the cellulose acetate fibers described herein may be substantially free of photodegradation agents.
- the fibers may include not more than about 1, 0.75, 0.50, 0.25, 0.10, 0.05, 0.025, 0.01, 0.005, 0.0025, or 0.001 weight percent of photodegradation agent, based on the total weight of the fiber, or the fibers may include no photodegradation agents.
- photodegradation agents include, but are not limited to, pigments which act as photooxidation catalysts and are optionally augmented by the presence of one or more metal salts, oxidizable promoters, and combinations thereof.
- Pigments can include coated or uncoated anatase or rutile titanium dioxide, which may be present alone or in combination with one or more of the augmenting components such as, for example, various types of metals.
- photodegradation agents include benzoins, benzoin alkyl ethers, benzophenone and its derivatives, acetophenone and its derivatives, quinones, thioxanthones, phthalocyanine and other photosensitizers, ethylene-carbon monoxide copolymer, aromatic ketone-metal salt sensitizers, and combinations thereof.
- the cellulose acetate fibers described herein may be substantially free of biodegradation agents and/or decomposition agents.
- the fibers may include not more than about 1, 0.75, 0.50, 0.25, 0.10, 0.05, 0.025, 0.01, 0.005, 0.0025, 0.0020, 0.0015, 0.001, 0.0005 weight percent of biodegradation agents and/or decomposition agents, based on the total weight of the fiber, or the fibers may include no biodegradation and/or decomposition agents.
- biodegradation and decomposition agents include, but are not limited to, salts of oxygen acid of phosphorus, esters of oxygen acid of phosphorus or salts thereof, carbonic acids or salts thereof, oxygen acids of phosphorus, oxygen acids of sulfur, oxygen acids of nitrogen, partial esters or hydrogen salts of these oxygen acids, carbonic acid and its hydrogen salt, sulfonic acids, and carboxylic acids.
- biodegradation and decomposition agents include an organic acid selected from the group consisting of oxo acids having 2 to 6 carbon atoms per molecule, saturated dicarboxylic acids having 2 to 6 carbon atoms per molecule, and lower alkyl esters of the oxo acids or the saturated dicarboxylic acids with alcohols having from 1 to 4 carbon atoms.
- Biodegradation agents may also comprise enzymes such as, for example, a lipase, a cellulase, an esterase, and combinations thereof.
- biodegradation and decomposition agents can include cellulose phosphate, starch phosphate, calcium secondary phosphate, calcium tertiary phosphate, calcium phosphate hydroxide, glycolic acid, lactic acid, citric acid, tartaric acid, malic acid, oxalic acid, malonic acid, succinic acid, succinic anhydride, glutaric acid, acetic acid, and combinations thereof.
- Cellulose acetate fibers described herein may also be substantially free of several other types of additives that have been added to other fibers to encourage environmental non-persistence.
- additives can include, but are not limited to, polyesters, including aliphatic and low molecular weight (e.g., less than 5000) polyesters, enzymes, microorganisms, water soluble polymers, modified cellulose acetate, water-dispersible additives, nitrogen-containing compounds, hydroxy-functional compounds, oxygen- containing heterocyclic compounds, sulfur-containing heterocyclic compounds, anhydrides, monoepoxides, and combinations thereof.
- polyesters including aliphatic and low molecular weight (e.g., less than 5000) polyesters, enzymes, microorganisms, water soluble polymers, modified cellulose acetate, water-dispersible additives, nitrogen-containing compounds, hydroxy-functional compounds, oxygen- containing heterocyclic compounds, sulfur-containing heterocyclic compounds, anhydrides, monoepoxides, and combinations thereof.
- the fibers described herein may include not more than about 0.5, 0.4, 0.3, 0.25, 0.1, 0.075, 0.05, 0.025, 0.01, 0.0075, 0.005, 0.0025, or 0.001 weight percent of these types of additives, or the cellulose acetate fibers may not include any of these types of additives.
- the dope can be extruded through a plurality of holes in spinneret 102 into a vertical spinning cabinet 104 to form continuous cellulose acetate filaments.
- filaments 103 may be drawn to form a few, tens, hundreds, or even thousands of individual filaments.
- each spinneret face has more than one cluster of holes to produce a group of filaments, and an individually-entangled cellulosic yarn is produced from each group of filaments.
- Each of these clusters may include between 2 and 300, 4 and 300, between 8 and 150, between 12 and 75, between 15 and 30 holes, which produces a yarn having the corresponding number of fibers.
- each group of filaments may include between 2 and 300, 4 and 300, between 8 and 150, between 12 and 75, between 15 and 30 individual fibers.
- Spinneret 102 may be operated at any speed suitable to produce filaments and bundles having desired size and shape.
- entangle refers to physically attaching a group of filaments to one another via filament deformation and/or intermingling.
- entangle is in at least one location along the length of the filament, which includes intermittently or continuously entanglement.
- filaments can be entangled by twisting and/or air jetting.
- respective individually-entangled yarns are not entangled with one another. Rather, only the group of filaments in these individually-entangled, or separately-entangled, yarns are entangled with one another.
- Individual bundles may be assembled into a filament yarn, as will be described in more detail below.
- a “filament yarn” or “tow yarn” refers to a yarn formed from a plurality of continuous individual filaments.
- the filament yarn may be of any suitable size and, in some embodiments, may have a total denier between 10 and 3000, between 20 and 500, between 30 and 300, between 40 and 150, or between 50 and 100.
- the individual filaments, which are extruded in a generally longitudinally aligned manner and which ultimately form the filament yarn may also be of any suitable size.
- each filament may have a linear denier per filament (weight in g of 9000m fiber length) between 0.25 and 50, between 0.5 and 25, between 1 and 10, between 2 and 6, or between 3 and 5, measured according to ASTM D1577-01 using the FAVIMAT vibroscope procedure.
- filament refers to an elongated, continuous single strand fiber and is distinguished from a staple fiber, which has been cut to a specified length.
- the individual filaments discharged from the spinneret may have any suitable transverse cross-sectional shape.
- Exemplary cross-sectional shapes include, but are not limited to, circular or any shape other than circular (irregular), such as Y-shaped, I-shaped (dog bone), closed C-shaped, tri-lobal, multi-lobal, X-shaped, or crenulated.
- a filament When a filament has a multi-lobal cross- sectional shape, it may have at least 4, 5, or 6 or more lobes.
- the filaments may be symmetric along one or more, two or more, three or more, or four or more axes, and, in other embodiments, the filaments may be asymmetrical.
- the term “cross-section” generally refers to the transverse cross-section of the filament relative to the longitudinal axis of the filament.
- the cross-section of the filament may be determined and measured using Quantitative Image Analysis (QIA).
- QIA Quantitative Image Analysis
- the shape factor of the individual cellulose acetate (or other cellulose ester) filaments or fibers can be at least about 1, 1.01, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2, 2.25, 2.5, 2.75, 3, or 3.25 and/or not more than about 5, 4.8, 4.75, 4.5, 4.25, 4, 3.75, 3.5, 3.25, 3, 2.75, 2.5, 2.25, 2, 1.75, 1.5, or 1.25. (Note: these values may also be expressed as ratios of the listed numbers to 1 – e.g., 1.45:1).
- the shape factor of filament or fiber having a round cross-sectional shape is 1.
- the shape factor can be calculated from the cross-sectional area of a filament or fiber, which can be measured using QIA.
- the cross-sectional shape of the filament or fiber may also be compared to a round cross-section according to its equivalent diameter, which is the equivalent diameter of a round filament or fiber having a cross- sectional area equal to a given filament or fiber.
- cellulose acetate filaments or fibers according to embodiments of the present invention can have an equivalent diameter of at least about 0.0022, 0.0023, 0.0024, 0.0025, 0.0030, 0.0033, 0.0035, 0.0040, 0.0045, 0.0050, 0.0055, 0.0060, 0.0065, 0.0070, 0.0073, 0.0075, 0.0080, 0.0085, 0.0090, 0.0095, 0.0100, 0.0103, 0.0104, 0.0105, 0.0110, 0.0112, 0.0115, 0.0120, 0.0125, 0.0126, 0.013, 0.014, or 0.015 mm.
- the cellulose acetate filaments or fibers may have an equivalent diameter of not more than about 0.0400, 0.0375, 0.036, 0.0359, 0.0350, 0.0033, 0.0327, 0.0325, 0.0300, 0.0275, 0.0250, 0.0232, 0.0225, 0.0200, 0.0179, 0.0175, 0.016, 0.0150, 0.0127, 0.0125, or 0.0120 mm.
- the equivalent diameter is calculated from the cross-section of a filament or fiber, measured using QIA.
- the cross-section of a cellulose acetate fiber is shaped with many lobes.
- the dope after the dope is spun through the spinneret, it can take on a round-shaped cross-section. After rapid evaporation of the solvent from the surface, a skin layer on the surface of the fiber can form. After that, evaporation of the solvent from the inside of the fiber an cause the skin layer to cave in toward the fiber cross-section, giving rise to the final multi-lobal cross-section.
- the cross-section can be crenulated, which is defined as having an irregularly wavy or serrated outline.
- the filaments or fibers 103 discharged from cabinet 104 may be at least partially coated with at least one fiber finish by at least one finish applicator 106 to produce coated filaments 107.
- fiber finish and “finish” refer to any suitable type of coating that, when applied to a fiber, modifies friction exerted by and on the fiber, and alters the ability of the fibers to move relative to one another and/or relative to a surface. Finishes are not the same as adhesives, bonding agents, or other similar chemical additives which, when added to fibers, prevent movement between the fibers by adhering them to one another. Finishes, when applied, continue to permit the movement of the fibers relative to one another and/or relative to other surfaces, but may modify the ease of this movement by increasing or decreasing the frictional forces. In some cases, finishes may not modify the frictional forces between fibers, but can, instead, impart one or more other desirable properties to the final coated fiber.
- the filaments or yarns may include at least two finishes applied to all or a portion of its surface at one or more points during the fiber production process.
- the fibers may only include one finish while, in other cases, the fibers may not include any finish at all.
- the finishes may be applied as a blend of two or more different finishes, or the finishes may be applied separately at different times during the process.
- the fibers may be at least partially coated with a spinning or spin finish applied to the filament yarn at one or more points during the process of forming the fibers.
- the spinning finish may be added to the fiber just after spinning.
- the spinning finish may be added to the filament yarn just prior to subsequent fiber processing, such as texturing or crimping, if applicable. In some cases, no spinning finish may be applied.
- Any suitable method of applying the spinning finish may be used and can include, for example, spraying, wick application, dipping, or use of squeeze, lick, or kiss rollers.
- the spinning finish may be of any suitable type and can be present on the filaments or fibers in an amount of at least about 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.70, 0.80, 0.90, or 1 percent finish-on-yarn (FOY).
- the spinning finish may be present in an amount of not more than about 10.0, 9.0, 8.0, 7.0, 6.0, 5.0, 4.0, 3.0, 2.0,1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.90, 0.80, 0.75, 0.70, 0.65, 0.60, or 0.50 percent finish-on-yarn (FOY) based on the total weight of the dried fiber.
- FOY finish on yarn refers to the amount of finish on the fiber or filament, yarn less any added water.
- One or two or more types of spinning finishes may be used. In some cases, the spinning finish may be hydrophobic.
- the top-coat (and/or spinning) finish may include other additives such as, for example, an anti-static agent.
- the finish may also include one or more other additives such as a wetting agent, antioxidants, biocides, anti-corrosion agents, pH control agents, emulsifiers, and combinations thereof. It is also possible that one or more additives may be added to a fiber as a coating, but without additional friction- modifying properties.
- any suitable anti-static agent may be used and, in some cases, the anti-static agent may include polar and/or hydrophilic compounds.
- additives may be present in any suitable amount such as, for example, at least about 0.10, 0.15, 0.20, 0.25, 0.30, or 0.35 weight percent and/or not more than about 3, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1, 0.90, 0.80, 0.70, 0.60, or 0.50 weight percent, based on the total weight of the fiber.
- the coated fiber may exhibit a static half-life of not more than about 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 22, 20, 17, 15, 12, 10, 8, 5, 3, 2, 1.5, or 1 second, measured according to AATCC 84-2011.
- the fibers may have a static half-life of not more than about 30, 25, 20, 18, 15, 12, 10, or 8 minutes.
- the static half-life of the coated fiber may be at least about 30 seconds, at least about 1 minute, at least about 5, 8, 10, 15, 20, 30, 40, 50, 60, 75, 90, or 100 minutes and/or not more than about 120, 110, 100, 90, 75, 60, 45, 40, 35, 30, 20, 15, or 12 minutes, measured according to AATCC 84-2011. [0062] In some embodiments, this may be not more than 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, or 5 percent of the static half- life of an identical but uncoated fiber.
- the static half-life of the coated fiber may be at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95 percent less than the static half-life of an identical but uncoated fiber.
- the coated fibers described herein may have a surface resistivity (Log R) of at least about 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, or 9 and/or not more than about 11, 10.5, 10, 9.75, 9.5, 9.25, 9, 8.75, 8.5, 8.25, 8, 7.75, 7.5 measured according to AATCC TM76-2011.
- the surface resistivity was measured using a Monroe Electronics resistivity meter (Model No. 272A) connected to a Keithley Instruments isolation box (Model No. 6104) using an isolation cup for measuring the resistivity of the fibers.
- the surface resistivity (Log R) is calculated by multiplying the surface resistance by the ratio of the length of the area being tested to its width and expressing the result as the base 10 logarithm of the calculated value.
- the fibers or filament yarns may be at least partially coated with at least one spinning finish and at least one top-coat finish.
- the total amount of all finishes present on the fibers or filament yarns according to embodiments of the present invention can be at least about 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, 1.0, or 1.05 percent FOY and/or not more than about 10, 9, 8, 7, 6, 5, 4, 3, 2, 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.90, 0.80, 0.75, 0.70, 0.65, 0.60, 0.55, 0.50, or 0.45 percent FOY, based on the total weight of the dried fiber.
- the amount of finish on the fibers as expressed by weight percent may be determined by solvent extraction according to ASTM D2257.
- the filament yarn when the filament yarn is coated with a spinning and/or top-coat finish, the filament yarn may exhibit a fiber-to-fiber (F/F) coefficient of friction (COF) of at least about 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, or 0.40 and/or not more than about 0.55, 0.50, 0.45, 0.42, 0.40, 0.35, 0.33, 0.30, 0.25, 0.20, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, or 0.06.
- F/F fiber-to-fiber
- COF fiber-to-fiber coefficient of friction
- F/F coefficient of friction (COF) of continuous filaments can be determined according to ASTM D3412 with the specified yarn parameters, a speed of 100 m/min, an input tension of 10 grams, and a single twist applied to the filament.
- yarns described herein may have a F/F coefficient of friction value within one or more of the above ranges measured using a continuous tension tester electronic device (CTT-E) according to ASTM D3412 with the specified yarn parameters, a speed of 20 m/min, an input tension of 10 grams, and a single twist applied to the filament.
- CTT-E continuous tension tester electronic device
- filament yarns coated with a spinning and/or top-coat finish may exhibit a fiber-to- metal (F/M) coefficient of friction of at least about 0.01, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.57, 0.60, or 0.65 and/or not more than about 0.80, 0.75, 0.70, 0.65, 0.60, 0.55, 0.50, 0.45, or 0.40.
- Values for the F/M coefficient of friction of continuous filaments can be determined according to ASTM D3108 with the specified yarn parameters, a speed of 100m/min, and an input tension of 48 grams.
- yarns described herein may have a F/M coefficient of friction value within one or more of the above ranges measured using a continuous tension tester electronic device (CTT-E) according to ASTM D3108 with the specified yarn parameters, a speed of 100 m/min, and an input tension of 10 grams.
- CTT-E continuous tension tester electronic device
- the coated fibers as described herein may also exhibit higher-than- expected strength.
- the coated fibers may be formed from filaments that exhibit a tenacity of at least about 0.5, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, 1.0, 1.05, 1.1, 1.15, 1.20, 1.25, 1.30, or 1.35 grams-force/denier (g/denier) and/or not more than 2.50, 2.45, 2.40, 2.35, 2.30, 2.25, 2.20, 2.15, 2.10, 2.05, 2.00, 1.95, 1.90, 1.85, 1.80, 1.75, 1.70, 1.65, 1.60, 1.55, 1.50, 1.47, 1.45, or 1.40 g/denier, and/or between 0.5 and 3.0, between 1 and 2, or between 1.25 and 1.5 g/denier, as measured according to ASTM D3822.
- the elongation at break of the coated fibers can be at least about 5, 6, 10, 15, 20, or 25 percent and/or not more than about 50, 45, 40, 35, or 30 percent, and/or between 5 and 50, between 10 and 40, or between 20 and 30, as measured according to ASTM D3822.
- fibers and filament yarns described herein include little or no plasticizer and have unexpectedly been shown to exhibit enhanced biodegradability under industrial, home, and soil conditions, even as compared to cellulose acetate fibers with higher levels of plasticizer.
- the fibers described herein can include less than about 50, 30, 27, 25, 22, 20, 17, 15, 12, 10, 9.5, 9, 8.5, 8, 7.5, 7, 6.5, 6, 5.5, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5, 0.25, or 0.10 percent plasticizers, based on the total weight of the fiber and/or yarns, or the fibers may include no plasticizer.
- the plasticizer may be incorporated into the fiber itself by being blended with the solvent dope or cellulose acetate flake, or the plasticizer may be applied to the surface of the fiber or filament by spraying, by centrifugal force from a rotating drum apparatus, or by an immersion bath.
- plasticizers that may or may not be present in or on the fibers can include, but are not limited to, aromatic polycarboxylic acid esters, aliphatic polycarboxylic acid esters, lower fatty acid esters of polyhydric alcohols, and phosphoric acid esters.
- Further examples can include, but are not limited to, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, dimethoxyethyl phthalate, ethyl phthalylethyl glycolate, butyl phthalylbutyl glycolate, tetraoctyl pyromellitate, trioctyl trimellitate, dibutyl adipate, dioctyl adipate, dibutyl sebacate, dioctyl sebacate, diethyl azelate, dibutyl azelate, dioctyl azelate, glycerol, trimethylolpropane, pentaerythritol, sorbitol, glycerin triacetate (triacetin), diglycerin tetracetate, triethyl phosphate, tributyl phosphate
- the fibers of the present invention may not include any type of plasticizer or other additive, and can consist essentially of, or consist of, cellulose acetate and not more than 1 percent FOY of a spinning finish.
- the cellulose acetate fibers described herein may not have undergone additional treatment steps designed to enhance the biodegradability of the fibers.
- the fibers may not have been hydroylzed or treated with enyzmes or microorganisms.
- the fibers may include not more than about 1, 0.75, 0.5, 0.25, 0.1, 0.05, or 0.01 weight percent of an adhesive or bonding agent and may include less than 1, 0.75, 0.5, 0.25, 0.1, 0.05, or 0.01 weight percent of modified or substituted cellulose acetate.
- the fibers may not include any adhesive or bonding agent and may not be formed from any substituted or modified cellulose acetate.
- Substituted or modified cellulose acetate may include cellulose acetate that has been modified with a polar substituent, such as a substituent selected from the group consisting of sulfates, phosphates, borates, carbonates, and combinations thereof.
- the cellulose acetate fibers are passed through at least one entanglement (TF) jet or discharged from at least one entanglement nozzle 108.
- the TF jets expose the cellulose acetate fibers to turbulent air such that one or more nodes are formed along the length of the yarn. Formation of these nodes helps with spinning, weaving, and processability of the yarn.
- the TF jets may be blown at a pressure between 10 and 20 pounds per square inch (psi).
- the yarn has an entanglement node density within a range between 1 and 50, between 2 and 30, between 4 and 20, or between 6 and 15 nodes per foot.
- the resulting individually-entangled yarns formed from the cellulose acetate fibers have a moisture content within a range between 3.5 and 30 percent, 3.5 and 25 percent, 3.5 and 20 percent, 3.5 and 15 percent, 4 and 10 percent, 4 and 8 percent, or 5 and 7 percent based on the total weight of the yarn.
- the resulting individually-entangled yarns formed from the cellulose acetate fibers have a residual solvent content within a range between 0 and 30 percent, between 2 and 20 percent, or between 4 and 15 percent based on the total weight of the yarn.
- the resulting individually-entangled yarns 109 are routed, via at least one yarn guide 110, towards at least one winder 112.
- the newly-formed yarns may be accumulated onto cores or tubes and the cores or tubes may be removable from winders 112, with the resulting individually- entangled yarns wound around the cores or tubes, as individual yarn packages of cellulosic material.
- yarn guide 110 receives a plurality of individually-entangled yarns 109 entangled by entanglement nozzle 108 (shown in FIG.1), and then routes yarns 109 towards winders 112 to produce one or more yarn packages.
- each yarn guide 110 includes a guide arm 116 that is individually capable of routing one or more yarns 109 towards winders 112.
- Each winder 112 includes a rotatable spool 118, and at least one core 120 is removably coupled to and rotatable with rotatable spool 118 such that yarns 109 may be wound or co-wound thereon.
- each spool 118 may receive more than one core 120 thereon.
- a plurality of individually-entangled yarns 109 may be wound around each common core 120.
- the number of yarns wound or co-wound on core 120 is not more than 20, not more than 15, not more than 10, not more than 5, or not more than 4.
- co-wound refers to the winding of more than one yarn around a common core at the same time.
- spinnerets 102 shown in FIG.1) are modified to output more than one distinct filament grouping that each produces an individually-entangled yarn 109.
- core 120 has a substantially cylindrical shape. In other words, core 120 does not include flanges, or any other structure that provides lateral support to yarns wound on core 120, defined at terminal ends of core 120. [0081] In one embodiment or in combination with any other mentioned embodiments, core 120 has a length between 2 and 24, between 4 and 12, or between 5 and 8 inches. [0082] In one embodiment or in combination with any other mentioned embodiments, core 120 is made of a non-metallic material. Exemplary non- metallic materials can include a cardboard material and/or a plastic material.
- two individually-entangled yarns 109 are wound around a common spool 118, which may have one or more cores 120 positioned thereon.
- One or more yarn sections may be formed on each core 120, and each yarn section can include one or more individually-entangled yarns co-wound around core 120.
- These yarns 109 are not twisted with each other on core 120. That is, even when more than one yarn 109 is routed towards a winder 112 from a single guide arm 116, these yarns 109 are combined and co-wound on at least one common section of core 120 without being twisted or entangled with one another before reaching the winder 112. Thus, the respective yarns 109 are unwindable from core 120 individually.
- each yarn section may have an individual weight of less than 10 pounds, less than 8 pounds, less than 6 pounds, less than 5 pounds, less than 4 pounds, or less than 2 pounds.
- a first guide arm 122 routes a first yarn 124 towards a first core 126 on a first spool 127
- a second guide arm 128 routes a second yarn 130 towards a second core 129 on first spool 127
- a third guide arm 132 routes a third yarn 134 towards a third core 131 on a second spool 133
- a fourth guide arm 138 routes a fourth yarn 140 towards a fourth core 135 on second spool 133.
- yarns 124, 130, 134, and 140 are wound around their respective cores 126, 129, 131, and 135 to produce four yarn packages 142 simultaneously.
- first spool 127 having two yarn packages 142 formed thereon is illustrated.
- one yarn package 142 includes first core 126 and a first yarn section 144 formed from first yarn 124
- another yarn package 142 includes second core 129 and a second yarn section 146 formed from second yarn 130.
- each yarn package 142 is individually removable from first spool 127.
- yarn package 142 associated with first core 126 may be removed, and then yarn package 142 associated with second core 129 may be removed afterwards.
- the package sections have a reduced size and weight, which may enhance the processability of yarn 109 wound thereon.
- yarns 124 and 130 are wound around a common core 120 to form yarn sections 144 and 146 thereon that are similar to those illustrated in FIGS.3 and 4.
- a multi-section yarn package 137 may include yarn sections 144 and 146 spaced from one another on the common core 120.
- such a multi-section yarn package 139 may include yarn sections 144 and 146 adjacent to and in substantial contact with one another on the common core to enhance the stability of the yarn package 139.
- first guide arm 122 routes first yarn 124 towards first core 126
- second guide arm 128 routes second yarn 130 towards first core 126
- third guide arm 132 routes third yarn 134 towards second core 129
- fourth guide arm 138 routes fourth yarn 140 towards second core 129.
- Yarns 124 and 130 are wound around separate sections of first core 126
- yarns 134 and 140 are wound around separate sections of second core 129 to produce two multi-section yarn packages 150.
- one yarn package 150 includes first core 126, a first yarn section 152 formed from first yarn 124, and a second yarn section 154 formed from second yarn 130.
- the other yarn package 150 includes second core 129, a third yarn section 156 formed from third yarn 134, and a fourth yarn section 158 formed from fourth yarn 140.
- Yarn sections 152, 154, 156, and 158 may be spaced from one another, or may be adjacent to and in substantial contact with one another, on their respective cores 126 and 129.
- yarns 124, 130, 134, and 140 may be wound around a common core 120 to form yarn sections 152, 154, 156, and 158 thereon that are similar to those illustrated in FIG.6.
- Such a multi- section yarn package 155 may include yarn sections 152, 154, 156, and 158 spaced from one another on the common core 120.
- multi-section yarn package 155 may include yarn sections 152, 154, 156, and 158 adjacent to and in substantial contact with one another on the common core 120 to enhance the stability of the yarn package 155.
- first guide arm 122 routes first yarn 124 and second yarn 130 towards a fifth core 157
- second guide arm 128 routes third yarn 134 and fourth yarn 140 towards a sixth core 159.
- the yarn pairs are combined at the respective guide arms 122 and 128, but are not twisted or not permanently entangled before being wound on the respective cores 157 and 159.
- the yarn pairs define a combined yarn 160 that is wound around the respective cores 157 and 159 to enable two yarn packages 162 to be produced simultaneously.
- yarn package 162 includes combined yarn 160 wound around at least one common section of first core 157.
- combined yarn 160 is co-wound around core 157 along the length thereof.
- yarn package 162 has a single yarn section wound thereon formed from more than one yarn.
- “combined” refers to two or more yarns occupying at least one common section of a core. Combined yarns are capable of being individually unwound from a core (i.e., unwound at the same time, but not sequentially, as separate yarns).
- first guide arm 122 routes first yarn 124 and second yarn 130 towards first core 126
- second guide arm 128 routes third yarn 134 and fourth yarn 140 towards second core 129.
- the yarn pairs are combined at the respective guide arms 122 and 128, but are not twisted or not permanently entangled before being wound on first core 126.
- the yarn pairs define combined yarns 164 and 166 that are wound around the respective cores 126 and 129 to produce multiple yarn packages 168 simultaneously.
- one yarn package 168 includes first core 126 and a first yarn section 170 formed from combined yarn 164, and the other yarn package 168 includes second core 129 and a second yarn section 172 formed from combined yarn 166. Accordingly, each yarn package 168 has a yarn section wound thereon that is formed from more than one yarn (i.e., a combined yarn).
- yarns 164 and 166 are wound around a common core 120 to form yarn sections 170 and 172 thereon that are similar to those illustrated in FIG. 10.
- yarn sections 170 and 172 may be spaced from one another on the common core 120, or may be adjacent to and in substantial contact with one another on the common core to define a multi-section yarn package 173.
- the above embodiments are for example purposes only. The systems and methods described herein may be used to produce yarn packages having any number of yarns, combined yarns, and/or yarn sections.
- yarns 109 are wound around a respective core 120 in a helical pattern.
- each core may have a longitudinal axis 174, and yarns 109 may be wound on the core at an angle between 0.1 and 89.9, between 1 and 30, between 2 and 20, or between 5 and 12 degrees relative to longitudinal axis 174. Accordingly, yarn may be collected along the length of the core.
- the yarn packages produced as described above may have a combined weight, including at least the core and yarn wound thereon, between 1 and 40, between 2 and 3, between 4 and 20, or between 5 and 15 pounds.
- each wound yarn section has a width, as defined relative to longitudinal axis 174, between 1 and 8 inches, between 1.5 and 6 inches, or between 2 and 3 inches on the core.
- Cellulose acetate fibers, filaments, and/or yarns as described herein can be used to form woven and/or nonwoven webs that can be used in several types of fibrous articles.
- coated fibers as described herein may be suitable for use in forming fabrics that exhibit unexpected and improved properties, such as strength, durability, flexibility, softness, and absorbency.
- the fibers as described herein exhibit unique properties such as lower friction, higher strength, and more durability, which facilitate faster, more efficient, and more uniform processing of the fibers into webs.
- cellulose acetate fibers as described herein exhibit enhanced levels of environmental non-persistence, characterized by better-than-expected degradation under various environmental conditions. Fibers and fibrous articles described herein may meet or exceed passing standards set by international test methods and authorities for industrial compostability, home compostability, and/or soil biodegradability.
- a material must meet the following four criteria: (1) the material must be biodegradable; (2) the material must be disintegrable; (3) the material must not contain more than a maximum amount of heavy metals; and (4) the material must not be ecotoxic.
- biodegradable generally refers to the tendency of a material to chemically decompose under certain environmental conditions. Biodegradability is an intrinsic property of the material itself, and the material can exhibit different degrees of biodegradability, depending on the specific conditions to which it is exposed.
- disintegrable refers to the tendency of a material to physically decompose into smaller fragments when exposed to certain conditions.
- the cellulose acetate fibers can exhibit a biodegradation of at least 70 percent in a period of not more than 50 days, when tested under aerobic composting conditions at ambient temperature (28°C ⁇ 2°C) according to ISO 14855-1 (2012).
- the cellulose acetate fibers can exhibit a biodegradation of at least 70 percent in a period of not more than 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, or 37 days when tested under these conditions, also called “home composting conditions.” These conditions may not be aqueous or anaerobic. In some cases, the cellulose acetate fibers can exhibit a total biodegradation of at least about 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, or 88 percent, when tested under according to ISO 14855-1 (2012) for a period of 50 days under home composting conditions.
- biodegradation This may represent a relative biodegradation of at least about 95, 97, 99, 100, 101, 102, or 103 percent, when compared to cellulose subjected to identical test conditions.
- a material To be considered “biodegradable,” under home composting conditions according to the French norm NF T 51-800 and the Australian standard AS 5810, a material must exhibit a biodegradation of at least 90 percent in total (e.g., as compared to the initial sample), or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item.
- the maximum test duration for biodegradation under home compositing conditions is 1 year.
- the cellulose acetate fibers as described herein may exhibit a biodegradation of at least 90 percent within not more than 1 year, measured according 14855-1 (2012) under home composting conditions. In some cases, the cellulose acetate fibers may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 1 year, or the fibers may exhibit 100 percent biodegradation within not more than 1 year, measured according 14855-1 (2012) under home composting conditions.
- the fibers described herein may exhibit a biodegradation of at least 90 percent within not more than about 350, 325, 300, 275, 250, 225, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 90, 80, 70, 60, or 50 days, measured according 14855-1 (2012) under home composting conditions.
- the fibers can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 70, 65, 60, or 50 days of testing according to ISO 14855-1 (2012) under home composting conditions.
- the cellulose acetate fibers may be considered biodegradable according to, for example, French Standard NF T 51-800 and Australian Standard AS 5810 when tested under home composting conditions.
- the cellulose acetate fibers can exhibit a biodegradation of at least 60 percent in a period of not more than 45 days, when tested under aerobic composting conditions at a temperature of 58°C ( ⁇ 2°C) according to ISO 14855-1 (2012).
- the fibers can exhibit a biodegradation of at least 60 percent in a period of not more than 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, or 27 days when tested under these conditions, also called “industrial composting conditions.” These may not be aqueous or anaerobic conditions.
- the fibers can exhibit a total biodegradation of at least about 65, 70, 75, 80, 85, 87, 88, 89, 90, 91, 92, 93, 94, or 95 percent, when tested under according to ISO 14855-1 (2012) for a period of 45 days under industrial composting conditions.
- This may represent a relative biodegradation of at least about 95, 97, 99, 100, 102, 105, 107, 110, 112, 115, 117, or 119 percent, when compared to cellulose fibers subjected to identical test conditions.
- a material must exhibit a biodegradation of at least 90 percent in total, or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item.
- the maximum test duration for biodegradability under industrial compositing conditions is 180 days.
- the cellulose acetate fibers described herein may exhibit a biodegradation of at least 90 percent within not more than 180 days, measured according 14855-1 (2012) under industrial composting conditions.
- the cellulose acetate fibers may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 180 days, or the fibers may exhibit 100 percent biodegradation within not more than 180 days, measured according 14855-1 (2012) under industrial composting conditions.
- cellulose acetate fibers described herein may exhibit a biodegradation of least 90 percent within not more than about 175, 170, 165, 160, 155, 150, 145, 140, 135, 130, 125, 120, 115, 110, 105, 100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, or 45 days, measured according 14855-1 (2012) under industrial composting conditions.
- the cellulose acetate fibers can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 65, 60, 55, 50, or 45 days of testing according to ISO 14855-1 (2012) under industrial composting conditions.
- the cellulose acetate fibers described herein may be considered biodegradable according ASTM D6400 and ISO 17088 when tested under industrial composting conditions.
- the fibers or fibrous articles may exhibit a biodegradation in soil of at least 60 percent within not more than 130 days, measured according to ISO 17556 (2012) under aerobic conditions at ambient temperature.
- the fibers can exhibit a biodegradation of at least 60 percent in a period of not more than 130, 120, 110, 100, 90, 80, or 75 days when tested under these conditions, also called “soil composting conditions.” These may not be aqueous or anaerobic conditions.
- the fibers can exhibit a total biodegradation of at least about 65, 70, 72, 75, 77, 80, 82, or 85 percent, when tested under according to ISO 17556 (2012) for a period of 195 days under soil composting conditions. This may represent a relative biodegradation of at least about 70, 75, 80, 85, 90, or 95 percent, when compared to cellulose fibers subjected to identical test conditions.
- the cellulose acetate fibers as described herein may exhibit a biodegradation of at least 90 percent within not more than 2 years, 1.75 years, 1 year, 9 months, or 6 months measured according ISO 17556 (2012) under soil composting conditions.
- the cellulose acetate fibers may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 2 years, or the fibers may exhibit 100 percent biodegradation within not more than 2 years, measured according ISO 17556 (2012) under soil composting conditions.
- cellulose acetate fibers described herein may exhibit a biodegradation of at least 90 percent within not more than about 700, 650, 600, 550, 500, 450, 400, 350, 300, 275, 250, 240, 230, 220, 210, 200, or 195 days, measured according 17556 (2012) under soil composting conditions.
- the cellulose acetate fibers can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 225, 220, 215, 210, 205, 200, or 195 days of testing according to ISO 17556 (2012) under soil composting conditions.
- the cellulose acetate fibers described herein may meet the requirements to receive The OK biodegradable SOIL conformity mark of Vinçotte and to meet the standards of the DIN Gezza Biodegradable in soil certification scheme of DIN CERTCO.
- the cellulose acetate fibers or fibrous articles may include less than 1, 0.75, 0.50, or 0.25 weight percent of components of unknown biodegradability.
- the fibers or fibrous articles described herein may include no components of unknown biodegradability.
- the cellulose acetate fibers and fibrous articles described herein may have a volatile solids concentration, heavy metals and fluorine content that fulfill all of the requirements laid out by EN 13432 (2000).
- the cellulose acetate fibers may not cause a negative effect on compost quality (including chemical parameters and ecotoxicity tests).
- the cellulose acetate fibers or fibrous articles can exhibit a disintegration of at least 90 percent within not more than 26 weeks, measured according to ISO 16929 (2013) under industrial composting conditions.
- the fibers or fibrous articles may exhibit a disintegration of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent under industrial composting conditions within not more than 26 weeks, or the fibers or articles may be 100 percent disintegrated under industrial composting conditions within not more than 26 weeks.
- the fibers or articles may exhibit a disintegration of at least 90 percent under industrial compositing conditions within not more than about 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, or 10 weeks, measured according to ISO 16929 (2013).
- the cellulose acetate fibers or fibrous articles described herein may be at least 97, 98, 99, or 99.5 percent disintegrated within not more than 12, 11, 10, 9, or 8 weeks under industrial composting conditions, measured according to ISO 16929 (2013).
- the cellulose acetate fibers or fibrous articles can exhibit a disintegration of at least 90 percent within not more than 26 weeks, measured according to ISO 16929 (2013) under home composting conditions.
- the fibers or fibrous articles may exhibit a disintegration of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent under home composting conditions within not more than 26 weeks, or the fibers or articles may be 100 percent disintegrated under home composting conditions within not more than 26 weeks.
- the fibers or articles may exhibit a disintegration of at least 90 percent within not more than about 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, or 15 weeks under home composting conditions, measured according to ISO 16929 (2013).
- the cellulose acetate fibers or fibrous articles described herein may be at least 97, 98, 99, or 99.5 percent disintegrated within not more than 20, 19, 18, 17, 16, 15, 14, 13, or 12 weeks, measured under home composting conditions according to ISO 16929 (2013).
- the cellulose acetate fibers may be used to form textiles for agricultural, medical, food, and other applications, for example.
- the textile fabric can be prepared from yams, as described herein.
- textile fabrics are materials made from yams and that are either woven, knitted, crocheted, knotted, embroidered, braided/plaited, laced, or carpet piled.
- Textile fabrics can include geotextile fabrics, carpet pilings, and fabrics (which includes cloth).
- the geotextile fabrics as used in the context of a textile fabric herein are those that are woven or knitted.
- suitable types of textile fabrics formable from the cellulose acetate fibers can include, but are not limited to, clothing (undergarments, socks, hats, shirts, pants, dresses, scarves, gloves, etc.), bags, baskets, upholstered furnishings, window shades, towels, table cloths, bed coverings, flat surface coverings, in art work, filters, flags, backpacks, tents, handkerchiefs, rags, balloons, kites, sails, parachutes, automotive upholstery, protective clothing such as against heat for firefighters and welders, protective clothing for bullet armor or stab protection, medical textile fabrics such as implants, and agrotextile fabrics for crop protection.
- yarn production system 100 further includes at least one dope mixer 176 and a solvent recovery system 178.
- dope mixer 176 receives fresh solvent 179 and/or solvent 180 from solvent recovery system 178, and receives solids 182, such as the cellulose acetate flake described above.
- Dope mixer 176 dissolves solids 182 in solvent 180 to produce a dope mixture 184.
- dope mixture 184 has between about 15 and 40 percent dissolved solids, and between about 60 and 85 percent solvent, by weight of dope mixture 184.
- Dope mixture 184 is then provided to spinnerets 102 in a common cabinet 104 to produce cellulose acetate filaments 103 therefrom.
- spinnerets 102 can spin dope mixture 184 at a rate of between 200 and 2000, between 250 and 1000, or between 300 and 500 meters per minute when forming filaments 103.
- the spinning rate is determined by the surface speed of the godet.
- the dope temperature at the outlet of spinnerets 102 may be maintained at between 30 and 120, between 40 and 100, or between 50 and 75 °C during the spinning. These process conditions enable continuous filaments as described herein to be produced for forming into continuous yarn.
- two single-cluster spinnerets 186 spin dope mixture 184 to form filaments 103 therefrom.
- each spinneret 186 forms a group of filaments, such that a first group 188 and a second group 190 of filaments are formed and passed through common cabinet 104.
- cabinet 104 further includes an air inlet 192 and an air outlet 194.
- Air inlet 192 receives a stream of air 196, which is channeled through cabinet 104 as first and second groups 188 and 190 of filaments are passed through cabinet 104.
- Air 196 is passed by the filaments to remove at least a portion of the solvent therefrom.
- first and second groups 188 and 190 of filaments are passed through cabinet for a residence time of between about 0.1 and 2.0 seconds. The residence time is selected to remove a desired amount of solvent from filaments 103.
- filaments 103 discharged from cabinet 104 are routed towards finish applicator 106 to apply a finish to filaments 103.
- yarn production system 100 includes a first finish applicator 200 and a second finish applicator 202 positioned at separate locations outside cabinet 104.
- first finish applicator 200 applies a finish to first group 188 of filaments at a first location
- second finish applicator 202 applies a finish to second group 190 of filaments at a second location that is positioned a distance from the first location.
- this arrangement of finish applicators 106 facilitates the production of distinct yarns from the respective groups of filaments.
- the finish is applied to filaments 103 before being entangled into yarns.
- coated filaments 107 routed from finish applicators 200 and 202 may be entangled by entanglement nozzles 108.
- filaments 107 are entangled by air jets discharged from nozzles 108 to produce, for example, first yarn 124 and second yarn 130.
- a first nozzle 204 at a first location entangles filaments 103 to produce first yarn 124
- the first and second locations are positioned a distance from each other to facilitate the production of distinct yarns from the respective groups of filaments.
- first and second yarns 124 and 130 may, optionally, be routed on a godet roll 208 before being received at winders 112.
- Godet roll 208 may be either located upstream of entanglement nozzles 108, or may be located between entanglement nozzles 108 and winders 112. Godet roll 208 is rotatable at a controlled speeds to facilitate stretching first and/or second yarns 124 and 130 wound thereabout. For example, godet roll 208 is rotatable to moderate the tension on first and/or second yarns 124 and 130 from the pulling force provided by winders 112.
- godet roll 208 and/or winders 112 are operable to stretch yarns 124 and 130 to a draw ratio of less than 2 to 0.8, 1.7 to 0.8, 1.5 to 0.8, 1.3 to 0.81.2 to 0.8, 1 to 0.8, 2 to 1, 1.7 to 1, 1.5 to 1, 1.3 to 1, 1.2 to 1, 1.1 to 1 and 1.1 to 1.
- the individually-entangled yarns 124 and 130 are then routed towards yarn guides 110 and winders 112 as described above to produce cellulosic yarn packages, such as those illustrated in FIGS.3, 4, and 8.
- yarn production system 100 includes two multi-cluster spinnerets 210 within common cabinet 104.
- Spinnerets 210 spin dope mixture 184 to form filaments 103 therefrom.
- each spinneret 210 forms two distinct groups of filaments, such that a first group 212 and a second group 214 of filaments are formed by one spinneret 210, and a third group 216 and a fourth group 218 of filaments are formed by the other spinneret 210.
- yarn production system 100 includes a first finish applicator 220, a second finish applicator 222, a third finish applicator 224, and a fourth finish applicator 226 each positioned at separate locations outside cabinet 104.
- first finish applicator 220 applies a finish to first group 212 of filaments at a first location
- second finish applicator 222 applies a finish to second group 214 of filaments at a second location
- third finish applicator 224 applies a finish to third group 216 of filaments at a third location
- fourth finish applicator 226 applies a finish to fourth group 218 of filaments at a fourth location.
- Each respective location is positioned a distance from each of the other locations.
- Coated filaments 107 routed from finish applicators 220, 222, 224, and 226 may then be entangled by entanglement nozzles 108.
- filaments 107 are entangled by air jets discharged from nozzles 108 to produce, for example, first yarn 124, second yarn 130, third yarn 134, and fourth yarn 140.
- a first nozzle 228 at a first location entangles first group 212 of filaments to produce first yarn 124
- a fourth nozzle 234 at a fourth location entangles fourth group 218 of filaments to produce fourth yarn 140 Each respective location is positioned a distance from each of the other locations.
- Yarns 124, 130, 134, and 140 may then be routed towards godet roll 208 for optional further processing of the yarns, as described above.
- the individually-entangled yarns 124, 130, 134, and 140 may then be routed towards yarn guides 110 and winders 112 as described above to produce cellulosic yarn packages, such as those illustrated in FIGS.6 and 10.
- yarn production system 100 includes two single-cluster spinnerets 186 within common cabinet 104.
- Yarn production system 100 also includes a first dope mixer 236 and a second dope mixer 238. Both dope mixers 236 and 238 receive solvent 180 from solvent recovery system 178, for example.
- first dope mixer 236 receives first solids 240 to form a first dope mixture 242
- second dope mixer 238 receives second solids 244 to form a second dope mixture 246.
- First and second solids 240 and 244 may both include cellulose acetate flake as described above.
- first and second dope mixtures 242 and 246 may be different from one another in terms of composition based on any of the variables disclosed herein. Accordingly, one spinneret 186 may spin first dope mixture 242 to produce first yarn 124, and the other spinneret 186 may spin second dope mixture 246 to produce second yarn 130 made of a different material than first yarn 124.
- the individually-entangled yarns 124 and 130 may then be routed towards yarn guides 110 and winders 112 as described above to produce cellulosic yarn packages, such as those illustrated in FIGS.3, 4, and 8, having yarn sections of different material wound thereon.
- yarns of the cellulosic yarn packages described above may be unwound from their cores, and then rewound onto one or more different cores mounted on a common shaft.
- the rewinding process produces yarn packages designed to meet criteria associated with subsequent processing of the yarns.
- Example criteria includes, but is not limited to, physical dimensions of a rewinding core and/or overall package size.
- the core of the rewind package may have a smaller diameter or a larger diameter than the at least one core of the feed package.
- the overall package size may be determined based on the weight of the package, the volume of yarn in the package, and/or the length of yarn in the package.
- FIG.14 illustrates an example yarn rewinding system 248 that may be used to rewind yarns 109 from a feed package 250 onto a rewind package 252.
- feed package 250 includes at least one core 120 and yarn 109 wound thereon, such as in any of the package configurations described above.
- Yarn 109 unwound from feed package 250 is processed by yarn rewinding system 248 and then rewound onto at least one core 254 to produce one or more rewind packages 252.
- System 248 optionally includes at least one yarn guide 256 and at least one godet roll 258, and also includes at least one finish applicator 260, at least one entanglement nozzle 262, and at least one tension controller 264.
- a facility may include multiple systems 248 to facilitate the production of multiple rewind packages 252 from multiple feed packages 250.
- Yarn guide 256 is similar to yarn guide 110 (shown in FIG. 1), and may be used to facilitate re-routing yarn 109 towards one or more rewind packages 252.
- Godet roll 258 is similar to godet roll 208 (shown in FIG.11), and may be used to moderate the tension on yarns 109 as they are unwound.
- Finish applicator 260 is similar to finish applicator 106, and may be used to apply a finish, as described above, to yarns 109 as they are unwound.
- Entanglement nozzle 262 is similar to entanglement nozzle 108 (shown in FIG. 1), and may be used to reapply entanglement to yarns 109, which may become at least partially unentangled from the unwinding thereof. The finish may be applied prior to or following re-entanglement of yarns 109 by entanglement nozzle 262.
- the finish is applied prior to re-entanglement of yarns 109 to improve the efficiency of the entanglement process.
- tension controller 264 may be used to control the tension in yarns 109 during the rewinding process to limit breakage of the yarns and to maintain entanglement of the yarns during rewinding. For example, in operation, tension controller 264 monitors the tension in unwound yarns 109 as they are routed from feed package 250 to rewind package 252.
- tension controller 264 is communicatively coupled with at least one of feed package 250, rewind package 252, or godet roll 258 (when in use) to control the operation thereof. That is, tension controller 264 is operable to adjust the rotational speed of at least one of feed package 250, rewind package 252, or godet roll 258 to maintain the tension in unwound yarns 109 within a threshold tension range that limits breakage and maintains entanglement, as described above.
- tension controller 264 controls operation of feed package 250, rewind package 252, and/or godet roll 258 to maintain the tensions of the separate yarns within 50 percent, 40 percent, 30 percent, 20 percent, 10 percent, 5 percent, or 1 percent of one another.
- Additional rewinding process parameters e.g., finish application and/or entanglement
- finish application and/or entanglement are also controlled to provide consistent properties in the separate yarns.
- example properties such as yarn elongation, yarn tenacity, entanglement node density, and finish level, are maintained consistent in the separate yarns.
- yarn 109 is generally unwound from feed package 250 by either “side” withdrawal or “over-end” withdrawal. These methods of withdrawal differ from one another by how the core is oriented relative to a direction of yarn withdrawal from the feed package.
- “side” refers to a withdrawal method in which the longitudinal axis of the core (e.g., longitudinal axis 174 as shown in FIGS.3, 4, 6, 8, and 10) is oriented perpendicularly relative to the direction of yarn withdrawal from the feed package, and the core rotates about its longitudinal axis during the yarn withdrawal.
- side withdrawal enables the yarns to be unwound from the core simultaneously and individually, as will be described in more detail below.
- over-end refers to a withdrawal method in which the longitudinal axis of the core (e.g., longitudinal axis 174) is oriented generally parallel with the direction of yarn withdrawal from the feed package.
- the core may either be rotatable or rotatably stationary during the yarn withdrawal.
- over-end withdrawal enables the yarns to be unwound from the core individually or sequentially, as will be described in more detail below.
- the withdrawal method used to unwind yarns from feed package 250 may be selected based on a desire to twist the yarns while being unwound. For example, no additional twisting is added to the yarns when unwound by side withdrawal. As illustrated in FIGS.
- system 248 includes a feed package 266 oriented for side withdrawal.
- Feed package 266 is formed from at least two individually-entangled yarns wound around at least one core 120 (e.g., a common core).
- the at least one core 120 is mountable on a common unwinding shaft 268, which is rotatable to enable the yarns to be unwound from feed package 266 simultaneously and individually.
- the yarns of feed package 266 are co-wound in a combined or sectional configuration, similar to yarn package 162 illustrated in FIG.8.
- first yarn 270 and a second yarn 272 co-wound on core 120 in a combined configuration, are separated from one another as the combined yarn is unwound from feed package 266.
- first yarn 270 is unwound from feed package 266 to produce a first single-yarn rewind package 274, and second yarn 272 is unwound from feed package 266 to produce a second single-yarn rewind package 276.
- At least some known yarn rewinding systems include multiple feed packages and multiple rewind packages arranged in a one-to-one ratio such that yarn from each feed package is routed to a single associated rewind package. Accordingly, many known yarn rewinding systems arrange the feed packages and the rewind packages in pairs, with the rewind package positioned vertically above its associated feed package, for example. In some embodiments, these existing yarn rewinding systems may be modified (i.e., retrofitted) to produce at least two single-yarn packages from a multi-yarn feed package, as described herein.
- first yarn 270 and second yarn 272 are routed from feed package 266 to the separate cores 254 of each rewind package 274 and 276 along unequal length yarn paths. That is, first yarn 270 is routed directly from core 120 of feed package 266 to first rewind package 274, and second yarn 272 is routed indirectly from core 120 of feed package 266 to second rewind package 276, with yarn path of first yarn 270 being shorter than the yarn path of second yarn 272.
- an existing yarn rewinding system may be modified to achieve this design.
- feed package 266, first rewind package 274, and second rewind package 276 may positioned at the illustrated predefined locations on an existing rewinding system.
- Feed package 266 and first rewind package 274 may define a feed package-rewind package pair, as described above.
- Second rewind package 276 is positioned adjacent to first rewind package 274 in the predefined rewind location typically associated with a different feed package- rewind package pair.
- second rewind package 276 receives second yarn 272 from feed package 266 rather than from a separate feed package.
- System 248 includes at least one yarn guide 256 positioned between feed package 266 and second rewind package 276. Second yarn 272 is routed through yarn guide 256 before being rewound. Accordingly, at least two single-yarn packages 274 and 276 may be produced using existing rewinding equipment.
- the tension in yarns 270 and 272 may be individually based on the length of yarn travel from feed package 266 to rewind packages 274 and 276. As illustrated in FIG.15, yarns 270 and 272 are routed to rewind packages 274 and 276 along unequal length yarn paths. Thus, the tension in yarns 270 and 272 may also be unequal. Differences in tension in yarns 270 and 272 may also be based on a wrap angle or a cumulative contact length of the yarns. The wrap angle of a yarn is defined by a total change in the direction of yarn withdrawal (e.g., in degrees) when the yarn contacts a rounded surface, such as when the second yarn 272 contacts yarn guide 256.
- yarns 270 and 272 are routed indirectly from feed package 266 to rewind packages 274 and 276 along equal length yarn paths. Specifically, yarns 278 are unwound from feed package 266 and routed towards yarn guide 256. Yarns 278 are then separated prior to or at the at least one yarn guide 256 into its individually-entangled yarns 270 and 272, which are then routed to their respective rewind packages 274 and 276.
- Yarn guide 256 is positioned approximately equidistant from rewind packages 274 and 276.
- the tension in yarns 270 and 272 may inherently be approximately equal based on at least one of the equal length yarn paths, and/or the equal cumulative wrap angles or the equal cumulative contact lengths defined by contact between yarns 270 and 272 against yarn guide 256.
- the withdrawal method used to unwind yarns from feed package 250 may be selected based on a desire to twist the yarns while being unwound. For example, the yarns are twisted when unwound by over-end withdrawal.
- system 248 includes a feed package 280 oriented for over-end withdrawal.
- Feed package 280 is formed from at least two individually-entangled yarns wound around at least one core 120 (e.g., a common core) in a sectioned configuration.
- the at least one core 120 is mountable on common unwinding shaft 268, which is operable to enable the yarns to be unwound from feed package 280 individually and sequentially, or simultaneously.
- one or more single yarn packages may be produced by rewinding the unwound yarns.
- a first yarn 282 that defines a first yarn section 284 on core 120 may be unwound from feed package 280 to produce a first single-yarn rewind package 286.
- a second yarn 288 that defines a second yarn section 290 on core 120 may be unwound from feed package 280 to produce a second single-yarn rewind package 292.
- system 248 includes feed package 280 oriented for over-end withdrawal.
- at least one additional individually- entangled yarn may be spliced to first yarn 282.
- the splicing may occur at any point when a desired splicing location on first yarn 282 is accessible, and/or when splicing the additional yarn at the desired splicing location would not interfere in any additional unwinding of first yarn 282 from feed package 280.
- the full length of first yarn 282 is unwound from core 120, and second yarn 288 is spliced onto first yarn 282 at a splicing location 294. Both first yarn 282 and second yarn 288 may then be rewound onto the same core 254 to produce a rewind package 292.
- less than the full length of first yarn 282 may be unwound from core 120 prior to splicing.
- any number of additional yarns may be spliced to increase the size of rewind package 292.
- splicing locations 294 may be visible on the final article.
- splicing locations 294 located at the same point in the article may cause a visual defect in the article. Accordingly, when system 248 produces multiple rewind packages 292 from multiple feed packages 280, splicing locations 294 on the different rewind packages 292 are different from one another to reduce the likelihood of forming a visual defect in a subsequently-formed article.
- system 248 includes feed package 280 oriented for over-end withdrawal.
- yarns 282 and 288 are unwound from feed package 280 simultaneously.
- yarns 282 and 288 are twisted with one another as they are unwound to produce a twisted yarn 296.
- Twisted yarn 296 is rewound on core 254 to produce a rewind package 298.
- FIGS. 17-19 are described in the context of feed packages having two yarn sections formed thereon, it should be understood that the embodiments illustrated therein may also be applicable to feed packages having more than two yarn sections formed thereon (e.g., packages 150 or 155).
- FIG.20 a tow production facility 300 is illustrated therein.
- Tow production facility 300 includes a dope forming system 302, a spinning system 304, a cabinet 306, a tow band forming system 308, a tow band crimping system 310, and a tow band baling system 312.
- Tow production facility 300 may be used in the production of a cellulose acetate tow band, as described herein.
- dope forming system 302 mixes cellulose acetate flake in a solvent to produce a cellulose acetate dope 314, similar to the dope produced in yarn production system 100 in Figure 1.
- Dope 314 produced in dope forming system 302 may be channeled to spinning system 304, which includes at least one spinneret 316 (shown FIGS.21 and 22).
- Dope 314 discharged from spinneret 316 forms continuous cellulose acetate fibers or filaments 318, which are discharged into cabinet 306 to recover solvent therefrom.
- Filaments 318 may then be processed at systems 308, 310, and 312 to produce a tow band 320.
- various cellulose acetate production assets may become underutilized and/or dormant.
- existing tow production assets may become underutilized as the demand for cellulose acetate tow decreases.
- the existing tow production facility 300 is converted (i.e., retrofitted) to produce cellulose acetate yarn, and to process the produced yarns to produce packages of cellulosic yarn, as described above.
- tow production facility 300 may be converted to a yarn production facility 322. This conversion may include utilizing at least some existing systems of tow production facility 300, installing new systems for use with at least some existing systems of tow production facility 300, and/or not utilizing at least one system of tow production facility 300.
- dope forming system 302, spinning system 304, and/or cabinet 306 of tow production facility 300 may be utilized in the production of cellulose acetate yarn.
- at least one of tow band forming system 308, tow band crimping system 310, or tow band baling system 312 is not utilized in the production of the cellulose acetate yarn.
- the newly installed systems facilitate the production of packages of cellulose acetate yarn.
- the newly installed systems include one or more systems of yarn production system 322, such as finish applicators 106, entanglement nozzles 108, yarn guides 110, and/or winders 112 installed downstream of spinning system 304.
- the newly installed systems may also include one or more separators 328 capable of separating tow band filaments into two or more groups of filaments, each group corresponding to its own distinct yarn.
- the filaments may be entangled to produce the yarns, and then wound onto cores or tubes to produce packages 329 of yarn, which are removable from winders 112.
- winders 112 are spaced less than 20 feet, less than 10 feet, less than 5 feet, or less than 3 feet from the location from the location of entanglement (i.e., the location of entanglement nozzles 108 near the bottom of cabinet 306).
- yarns may be routed towards one or more additional winders when the capacity of winders 112 near the bottom of cabinet 306 has been reached, such as due to space constraints and the increased spinning capacity of the tow assets.
- yarn production facility 322 may include one or more remote winders 330 located a distance from the existing yarn production assets.
- remote winders 330 may be at least 10 feet, at least 20 feet, at least 30 feet, at least 40 feet, at least 50 feet, between 10 and 50 feet, between 20 and 40 feet, or between 20 and 30 feet from the location of cabinet 306.
- conversion of tow production facility 300 to yarn production facility 322 may also include modifying spinning system 304 in a manner that facilitates production of yarns rather than a tow band.
- spinnerets of tow production facility 300 may be single-cluster spinnerets that produce a single grouping of filaments.
- one or more spinnerets 316 (shown in FIGS.21 and 22) of tow production facility 300 may be either replaced or modified to have a plurality of groups of openings for producing a plurality of groups of filaments.
- the groups filaments formed therefrom may be individually entangled and wound to produce packages 329, as described above.
- the group of filaments produced from the grouped section of openings may be separated and then wound at remote winders 330, as will be described in more detail below.
- Spinnerets 316 described herein may have at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, or at least 10 groups of openings for forming the distinct groups of filaments.
- dope forming system 302 includes at least one dope mixer 332, solvent recovery system 326, and dope pump 324.
- dope mixer 332 receives fresh solvent 334 and/or recovered solvent 336 from solvent recovery system 326.
- Dope mixer 332 may also receive solids 338, such as the cellulose acetate flake described above, for mixing with the solvents 334 or 336 to produce cellulose acetate dope 314.
- Dope 314 is then provided to at least one spinneret 316 in spinning system 304 to produce cellulose acetate filaments 318 therefrom.
- spinnerets 316 spin dope 314 at a rate of greater than 500, greater than 600, greater than 700, greater than 800, or greater than 1000 meters per minute when forming filaments 318.
- spinning system 304 spins filaments 318 into cabinet 306 at greater than 300, greater than 500, greater than 750, greater than 1000, greater than 1250, greater than 1500, between 300 and 2000, between 300 and 1500, between 500 and 1500, between 750 and 1500, between 1000 and 1500, or between 1250 and 1500 denier per cabinet.
- filaments 318 are routed to finish applicators 106 and then entanglement nozzles 108 to produce individually-entangled yarns 334, as described above. Some yarns 334 are routed from a godet roll 342 to winders 112 near the bottom of the respective cabinet 306, as described above. In addition, yarn production facility 322 may include increase yarn winding capacity to accommodate the increased output of the initial tow production asset. Accordingly, additional yarns 334 may be routed from godet roll 342 to remote winders 330 to produce additional packages 329 therefrom. [00164] In the illustrated embodiment, filaments 318 are separated into groups of filaments having a reduced denier than the total output of spinning system 306.
- filaments 318 may be spun into a plurality of cabinets 306, and filaments 318 discharged from each cabinet 306 may be routed to at least one separator 328 for separating filaments 318 into the plurality of groups.
- a separator 328 can be any that is known in the art capable of separating filaments 318 into the plurality of groups.
- An example of a separator includes a mechanical separator.
- separators 328 are operable to separate filaments 318 into groups each having a substantially equal denier.
- filaments 318 may be separated into groups each having a denier between 20 and 300, between 30 and 200, between 40 and 150, or between 50 and 100.
- Filaments 318 routed to remote winders 330 may be separated and entangled prior to being routed the remote distance, or may be routed to remote winders 330 and then separated and entangled.
- separators 328 are positioned near the bottom of cabinet 306 to separate filaments 318 prior to routing to remote winders 330.
- the separated and/or entangled groups of filaments 318 are routed to remote winders 330 through a plurality of separation channels 344, as illustrated in FIG.23.
- Separation channels 344 are sized to receive a single group of filaments 318 such that, when routed therethrough, filament crossing between the groups of filaments is limited or eliminated during the routing to remote winders 330.
- filaments 318 may be further entangled at remote winders 330.
- filaments 318 may have a finish applied thereto and then be routed, without separation, the remote distance to remote winders 330. Filaments 318 may then be separated by separator 328, individually-entangled by entanglement nozzles 108, and wound to produce packages 329 at remote winders 330.
- filaments 318 are spun into a plurality of cabinets 306 and then combined to produce a band 320 of filaments with band forming system 308, for example. The band of filaments may then be separated by separators 328 into a plurality of groups of filaments, entangled, and wound.
- the band may be conveyed to the remote winders in a single conveyor channel prior to separation and entanglement, thus eliminating the need for separate yarn channels to prevent filaments from crossing between groups.
- separators 328 are operable to separate filaments 318 into groups each having a substantially equal denier.
- the filaments of band 320 may be separated into groups each having a denier between 20 and 300, between 30 and 200, between 40 and 150, or between 50 and 100.
- the groups each include no greater than 300, no greater than 1000, no greater than 5000, or no greater than 10,000 cellulosic filaments. These groups of filaments may then be wound at remote winders 330 to produce packages 329.
- the terms “including,” “includes,” and “include” have the same open-ended meaning as “comprising,” “comprises,” and “comprise.” [00172] As used herein, the terms “having,” “has,” and “have” have the same open-ended meaning as “comprising,” “comprises,” and “comprise.” [00173] As used herein, the terms “containing,” “contains,” and “contain” have the same open-ended meaning as “comprising,” “comprises,” and “comprise.” [00174] As used herein, the terms “a,” “an,” “the,” and “said” mean one or more.
- the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
- the preferred forms of the invention described above are to be used as illustration only, and should not be used in a limiting sense to interpret the scope of the present invention.
- a disclosed numerical range of 10 to 100 provides literal support for a claim reciting “greater than 10” (with no upper bounds) and a claim reciting “less than 100” (with no lower bounds).
- a listing of numerical values following a descriptor such as “at least” and “not more than,” provides literal support for a range based on all of the numerical values following that descriptor.
- each group of yarn is extruded from one spinneret, passes through the cabinet, then is threaded through a set of auxiliary devices before being wound onto separate cores to form a package on the winder.
- auxiliary devices To increase yarn production capacity, multiple groups of openings? can be incorporated into one spinneret, enabling the extrusion of multiple groups of filaments or yarns from a single spinneret.
- Example One to Four describe the production processes, respectively, of making conventional packages, conventional packages with increased capacity, combined packages with increased capacity, and sectional packages with increased capacity, using two spinnerets in one cabinet as the basic unit.
- Example One [00181] A first yarn was produced from the 1 st spinneret in one cabinet, and a second yarn was produced from the 2 nd spinneret in the same cabinet. The two yarns were kept separate in the cabinet through two yarn guides at the exit. After exiting the cabinet, two yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before being wound onto separate cores on a common winder spool.
- Example Two [00182] A first and a second yarn were produced from the 1 st spinneret in one cabinet, and a third and fourth yarn were produced from the 2 nd spinneret in the same cabinet. The four yarns were kept separate in the cabinet through four yarn guides at the exit. After exiting the cabinet, the yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before wounding onto cores. The first and second yarns were wound separately onto two cores on a common spool on the first winder. Similarly, the third and fourth yarns were wound by using a second winder.
- Example Three A first and a second yarn were produced from the 1 st spinneret in one cabinet, and a third and fourth yarn were produced from the 2 nd spinneret in the same cabinet.
- the four groups of yarns were kept separate in the cabinet through four yarn guides at the exit. After exiting the cabinet, the yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before winding.
- the first and second yarns were then combined and threaded through a first yarn guide, co-wound on the same section of the first core on a winder spool.
- Example 4 A first and a second yarn were produced from the 1 st spinneret in one cabinet, and a third and fourth yarn were produced from the 2 nd spinneret in the same cabinet. The four groups of yarns were kept separate in the cabinet through four yarn guides at the exit. After exiting the cabinet, the yarns were individually lubricated before taken up by a shared godet roll.
- Table 1 summarizes the production setups, throughputs, and yarn package parameters of Example One to Four. All the examples were based on the same production conditions including the dope solids, dope temperature, draw ratio, and spinning speed in the ranges described in this disclosure.
- the yarn specifications were 75 denier/19 filaments, 2.0% FOY, 1.3 gpd tenacity, 21% elongation, and 11 entanglement nodes per foot.
- the package dimensions were measured using a ruler, and the package weight was obtained by weighing the package on a calibrated scale and subtracting the core weight.
- the helix angle was calculated from the known the winder speeds in the traverse and spool rotating directions. Examples 2-4 doubled the throughput compared to Example One due to the increase in the number of groups resulting from the change from conventional spinnerets to spinnerets with multiple hole groupings.
- Example 3 and Example 4 doubled the number of yarns per winder compared to Example One and Two by winding multiple yarns per core.
- Example 4 due to the sectional structure of the package, there is a small gap between sections defined as the section-to-section distance. As a result, the package weight in Example 4 is lower, and the helix angle is set higher to ensure package stability.
- TABLE 1 Comparison of Cellulose Acetate Yarn Production Setups, Throughputs, and Yarn Package Parameters Example Example Example One Example Two Three Example Four Settings Conventional Combined Sectional (One Cabinet) Package with Package with Package with Conventional Increased Increased Increased Package Capacity Capacity Capacity Number of S pinnerets 2 2 2 2 2 Number of C lusters/Spinneret 1 2 Number of Yarn G roups 2 4 4 4 Number of Lube A pplicators 2 4 4 4 Number of TF A pplicators 2 Number of Tension G uides 2 4 4 4 Number of Winders 1 2 1 1 Number of C ores/Winder 2 2 2 2 Number of S ections/Core 1 1 1 2 Number of Y arns/Se
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- Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
- Artificial Filaments (AREA)
Abstract
Methods of converting existing assets to increase cellulosic yarn production. The methods comprise converting an acetate tow production facility into an acetate yarn production facility, such as by installing a yarn winding system in the acetate tow production facility. The converted acetate yarn production facility may then be used to produce packages of wound acetate yarn.
Description
METHODS OF CONVERTING ASSETS TO INCREASE CELLULOSIC YARN PRODUCTION BACKGROUND [0001] Textile fabrics consisting of yarns are widely used in a variety of applications. These fabrics may be formed by weaving, knitting, crocheting, knotting, or felting yarn made of materials, such as, for example, polyesters, polyamides, acrylics, polyurethanes, glass, polypropylene, silk, and a variety of cellulosic materials. Cellulose acetate fibers are one type of cellulosic material known for their sustainability, biodegradability, and renewability. Traditionally, cellulose acetate fibers are formed by extruding dope from a spinneret to produce multiple filaments, which may then be joined to create multi-filament yarns. The possibility of increasing fiber production has been explored as the market for cellulose-based textiles has grown. However, there is a limit to the number of spinnerets that can be accommodated in existing spinning machine cabinets. In addition, adding additional spinning machines to a production facility or additional winders to an existing spinning machine is a time- consuming and expensive endeavor. [0002] Thus, it is desirable to increase cellulose acetate fiber production using existing equipment and processes without the need to invest in additional and expensive equipment. SUMMARY [0003] Provided herein is a method of producing cellulosic yarn. The method comprises spinning a plurality of cellulosic filaments into a cabinet at greater than about 300 denier per cabinet, and separating the plurality of cellulosic filaments into a plurality of groups of filaments. [0004] Also provided herein is a method of producing acetate yarn. The method comprises providing an acetate tow production facility comprising a dope forming system, a spinning system, a tow band forming system, a tow band crimping system, and a tow band baling system. The method also comprises converting the acetate tow production facility into an acetate yarn
production facility, wherein the converting comprises installing a yarn winding system downstream of the spinning system, and producing packages of acetate yarn using the acetate yarn production facility. The producing comprises forming a cellulose acetate dope using the dope forming system, spinning cellulose acetate filaments from the cellulose acetate dope using the spinning system, and winding the cellulose acetate filaments using the yarn winding system to produce the packages of acetate yarn. At least one of the tow band forming system, the tow band crimping system, or the tow band baling system is not utilized during the producing step. [0005] Also provided herein is a method of producing acetate yarn. The method comprises providing an acetate tow production facility comprising a dope forming system, a dope pump, a spinning system, a solvent recovery system, a finish application system, an entanglement system, and a yarn winding system. The method also comprises producing packages of acetate yarn using the acetate tow production facility. The producing comprises forming a cellulose acetate dope using the dope forming system, pumping cellulose acetate dope from the dope forming system to the spinning system using the dope pump, spinning cellulose acetate filaments using the spinning system, recovering solvent evaporated from the filaments using the solvent recovery system, applying a finish to the cellulose acetate filaments using the finish application system, individually-entangling groups of the filaments using the entanglement system to produce a plurality of individually-entangled cellulose acetate yarns, and winding the individually-entangled cellulose acetate yarns using the yarn winding system to produce packages of cellulose acetate yarn. The producing further comprises operating at least one of the dope forming system, the dope pump, or the solvent recovery system at less than 75 percent of its designed operating capacity. BRIEF DESCRIPTION OF THE FIGURES [0006] FIG. 1 is a schematic illustration of an example yarn production system.
[0007] FIG. 2 illustrates one example of the yarn guide and winding sub- assemblies shown in FIG.1. [0008] FIG.3 is a side view illustration of an example yarn package that may be produced as shown in FIG.2. [0009] FIG. 3A is a side view illustration of an example yarn package that may be produced as shown in FIG.2. [0010] FIG.4 is a side view illustration of another example yarn package that may be produced as shown in FIG.2. [0011] FIG.4A is a side view illustration of another example yarn package that may be produced as shown in FIG.2. [0012] FIG.5 illustrates another example of the yarn guide and winding sub- assemblies shown in FIG.1. [0013] FIG.6 is a side view illustration of an example yarn package that may be produced as shown in FIG.5. [0014] FIG. 6A is a side view illustration of an example yarn package that may be produced as shown in FIG.5. [0015] FIG.7 illustrates another example of the yarn guide and winding sub- assemblies shown in FIG.1. [0016] FIG.8 is a side view illustration of an example yarn package that may be produced as shown in FIG.7. [0017] FIG.9 illustrates another example of the yarn guide and winding sub- assemblies shown in FIG.1. [0018] FIG. 10 is a side view illustration of an example yarn package that may be produced as shown in FIG.9. [0019] FIG.10A is a side view illustration of an example yarn package that may be produced as shown in FIG.9. [0020] FIG.11 is a schematic illustration of an example portion of the yarn production system shown in FIG.1. [0021] FIG.12 is a schematic illustration of another example portion of the yarn production system shown in FIG.1. [0022] FIG.13 is a schematic illustration of another example portion of the yarn production system shown in FIG.1.
[0023] FIG. 14 is a schematic illustration of an example yarn rewinding system. [0024] FIG.15 illustrates an example of the yarn rewinding system shown in FIG.14 performing side withdrawal. [0025] FIG. 16 illustrates another example of the yarn rewinding system shown in FIG.14 performing side withdrawal. [0026] FIG. 17 illustrates an example flow diagram of the yarn rewinding system shown in FIG.14 performing over-end withdrawal. [0027] FIG.18 is a schematic illustration of the yarn rewinding system shown in FIG.14 performing over-end withdrawal. [0028] FIG.19 illustrates another example flow diagram of the yarn rewinding system shown in FIG.14 performing over-end withdrawal. [0029] FIG. 20 illustrates an example of a conversion of an acetate tow production system to an acetate yarn production system. [0030] FIG.21 illustrates another example of a conversion of an acetate tow production system to an acetate yarn production system. [0031] FIG.22 illustrates another example of a conversion of an acetate tow production system to an acetate s3yarn production system. [0032] FIG.23 illustrates an example of a separation channel (344). DETAILED DESCRIPTION [0033] The present application generally relates to systems and methods for use in increasing cellulosic yarn production, and yarn packages produced therefrom. Yarn production is increased by expanding the production capabilities of existing fiber spinning machines and/or by converting other assets (e.g., tow production assets) to yarn production assets. Such yarns can be utilized in expanded application opportunities in downstream fiber converting and end use apparel applications, for example. . The yarns can be produced by any type of dry or wet spinning processes known in the art. In one embodiment, wet spinning is defined as a process whereby at least one polymer is dissolved in at least one solvent to create a liquid solution. The solution is forced through a spinneret, and then comes into contact with a
coagulating bath, which causes the liquid to solidify into fibers. In another embodiment, dry spinning is defined as a process whereby at least one polymer is dissolved in at least one solvent and then extruded. As fibers emerge through the spinneret, the solvent is evaporated. [0034] Fiber spinning machines often include multiple spinnerets per cabinet, and the spinnerets each produce a yarn end that is then wound onto its own distinct core. As disclosed herein, the various sub-assemblies (i.e., spinning, finish application, entanglement, yarn guide, and/or winding) of an example production system are modified from existing assets to facilitate increasing their yarn output at an enhanced production capacity. For example, the spinning sub- assembly may be modified to increase the output of yarn ends from the production system. This may be accomplished by installing additional spinnerets near the top of an existing filament receiving section (e.g., a cabinet or liquid bath), or by modifying existing spinnerets to output more than one distinct filament grouping that each produces an individually-entangled yarn therefrom. Accordingly, the number of finish applicators, entanglers, yarn guides, and/or winding cores may be increased based on the increased number of yarns produced to accommodate the enhanced production capacity. [0035] In some of the embodiments described herein, the produced yarns are wound around at least one core on an existing common spool of the production system. The yarns may be wound in a winding configuration that enables the respective yarn ends to be unwindable from the core individually. By winding more than one yarn around the common spool, the winding capacity of the existing spinning machine is increased without having to modify the winding system, such as by increasing the number of spools, to accommodate the additional cores needed to receive any additional yarn ends. [0036] Thus, the yarn package configurations, and methods of production and processing thereof, disclosed herein enable yarn output to be increased on a per cabinet basis while still producing a package of distinct yarn ends that are easily separable from one another when being unwound from the common core. The increased yarn output is based on increased yarn production capacity, rather than an increased yarn production rate and/or speed. Thus, the
yarn production systems described herein may operate at the same production speed or a slower production speed than the existing asset from which is was modified, for example. [0037] The yarn packages disclosed herein also provide enhanced versatility to meet customer needs for varying package sizes and configurations. In addition, it should be understood that even though embodiments herein are disclosed in the context of cellulosic yarn production, the embodiments may also be applied to non-cellulosic yarn and fiber production. [0038] The fibers, filaments, and/or yarns as described herein may be formed from one or more cellulose esters including, but not limited to, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate formate, cellulose acetate propionate, cellulose acetate butyrate, cellulose propionate butyrate, and mixtures thereof. Although described herein with reference to “cellulose acetate,” it should be understood that one or more of the above cellulose acid esters or mixed esters may also be used to form the fibers, nonwovens, and articles as described herein. Various types of cellulose esters are described, for example, in U.S. Patent Nos.1,698,049; 1,683,347; 1,880,808; 1,880,560; 1,984,147, 2,129,052; and 3,617,201, each of which is incorporated herein by reference to the extent not inconsistent with the present disclosure. In some cases, other types of treated or regenerated cellulose (e.g., viscose, rayon, cupro, model, or lyocell) may or may not be used in forming fibers as described herein. In some cases, other types of recycle content material may or may not be used in forming fibers as described herein. Example recycle content material includes, but is not limited to, woven, knitted, or non-woven fabrics, thread, yarns, fiber fills, and various other plastic articles. [0039] When the fibers described herein are formed from cellulose acetate, it may be formed from cellulose diacetate, cellulose triacetate, or mixtures thereof. The cellulose acetate (or other cellulose ester) useful in embodiments of the present invention can have a degree of substitution in the range between 2.2 and 3, between 2.25 and 2.9, between 2.35 and 8, or between 2.4 and 2.7. As used herein, the term “degree of substitution” or “DS” refers to the average number of acetyl substituents per anhydroglucose ring of the cellulose polymer,
wherein the maximum degree of substitution is 3.0. In some cases, the cellulose acetate used to form fibers as described herein may have an average degree of substitution of at least about 1.95, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, or 2.3 and/or not more than about 2.9, 2.85, 2.8, 2.75, 2.7, 2.65, 2.6, 2.55, 2.5, 2.45, 2.4, or 2.35, with greater than 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99 percent of the cellulose acetate having a degree of substitution greater than 2.15, 2.2, or 2.25. In some cases, greater than 90 percent of the cellulose acetate can have a degree of substitution greater than 2.2, 2.25, 2.3, or 2.35. [0040] The cellulose acetate may have a weight-average molecular weight (Mw) of not more than 90,000, measured using gel permeation chromatography with N-methyl-2-pyrrolidone (NMP) as the solvent. In some case, the cellulose acetate may have a molecular weight of at least about 10,000, at least about 20,000, 25,000, 30,000, 35,000, 40,000, or 45,000 and/or not more than about 90,000, 85,000, 80,000, 75,000, 70,000, 65,000, 60,000, or 50,000, and/or between 10,000 and 90,000, between 20,000 and 80,000, between 30,000 and 70,000, or between 40,000 and 60,000. [0041] Referring now to the drawings, FIG.1 is a schematic illustration of an example yarn production system 100. The cellulose acetate or other cellulose ester used in the production of the fibers and/or yarns described herein may be formed by any suitable method known in the art. In some cases, cellulose acetate may be formed by reacting a cellulosic material such as wood pulp with acetic anhydride and a catalyst in an acidic reaction medium to form a cellulose acetate flake. The cellulose acetate or other cellulose ester used in the production of the fibers and/or yarns described herein may be formed by any suitable method, such as wet spinning, dry spinning, or melt spinning. In the case of wet or dry spinning, the flake may then be dissolved in a solvent to form a “dope” solution which can be filtered and sent through at least one spinneret 102, as shown in FIG.1, to form continuous cellulose acetate filaments or fibers 103. In some cases, up to about 1 weight percent or more of titanium dioxide or other delusterant may be added to the dope prior to filtration, depending on the desired properties and ultimate end use of the fibers. Example solvents include, but are not limited to, acetone, methyl ethyl ketone, methylene chloride,
dimethylformamide (DMF), dimethylacetamide (DMAC), dimethyl sulfoxide (DMSO), and combinations thereof. [0042] In some cases, the solvent dope or flake used to form the cellulose acetate fibers may include few or no additives in addition to the cellulose acetate. Such additives can include, but are not limited to, pigments, colorants, antimicrobials, UV stabilizers, flame retardants, antioxidants, thermal stabilizers, pro-oxidants, acid scavengers, inorganics, photodegradation agents, biodegradation agents, decomposition accelerating agents, polyesters, enzymes, microorganisms, water soluble polymers, modified cellulose acetate, water-dispersible additives, nitrogen-containing compounds, hydroxy- functional compounds, oxygen-containing heterocyclic compounds, sulfur- containing heterocyclic compounds, anhydrides, and monoepoxides, or combinations thereof. In some cases, the cellulose acetate fibers as described herein can include at least about 90, 90.5, 91, 91.5, 92, 92.5, 93, 93.5, 94, 94.5, 95, 95.5, 96, 96.5, 97, 97.5, 98, 98.5, 99, 99.5, 99.9, 99.99, 99.995, or 99.999 percent cellulose acetate, based on the total weight of the fiber. Fibers formed according to the present invention may include not more than about 10, 9.5, 9, 8.5, 8, 7.5, 7, 6.5, 6, 5.5, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5, 0.1, 0.01, 0.005, or 0.001 weight percent of additives other than cellulose acetate, including the specific additives listed herein. [0043] Cellulose acetate fibers can achieve higher levels of biodegradability and/or compostability without use of additives that have traditionally been used to facilitate environmental non-persistence of similar fibers. Such additives can include, for example, photodegradation agents, biodegradation agents, decomposition accelerating agents, and various types of other additives. Despite being substantially free of these types of additives, the cellulose acetate fibers and articles produced therefrom have unexpectedly been found to exhibit enhanced biodegradability and compostability when tested under industrial, home, and/or soil conditions. [0044] In some embodiments, the cellulose acetate fibers described herein may be substantially free of photodegradation agents. For example, the fibers may include not more than about 1, 0.75, 0.50, 0.25, 0.10, 0.05, 0.025, 0.01,
0.005, 0.0025, or 0.001 weight percent of photodegradation agent, based on the total weight of the fiber, or the fibers may include no photodegradation agents. Examples of such photodegradation agents include, but are not limited to, pigments which act as photooxidation catalysts and are optionally augmented by the presence of one or more metal salts, oxidizable promoters, and combinations thereof. Pigments can include coated or uncoated anatase or rutile titanium dioxide, which may be present alone or in combination with one or more of the augmenting components such as, for example, various types of metals. Other examples of photodegradation agents include benzoins, benzoin alkyl ethers, benzophenone and its derivatives, acetophenone and its derivatives, quinones, thioxanthones, phthalocyanine and other photosensitizers, ethylene-carbon monoxide copolymer, aromatic ketone-metal salt sensitizers, and combinations thereof. [0045] In some embodiments, the cellulose acetate fibers described herein may be substantially free of biodegradation agents and/or decomposition agents. For example, the fibers may include not more than about 1, 0.75, 0.50, 0.25, 0.10, 0.05, 0.025, 0.01, 0.005, 0.0025, 0.0020, 0.0015, 0.001, 0.0005 weight percent of biodegradation agents and/or decomposition agents, based on the total weight of the fiber, or the fibers may include no biodegradation and/or decomposition agents. Examples of such biodegradation and decomposition agents include, but are not limited to, salts of oxygen acid of phosphorus, esters of oxygen acid of phosphorus or salts thereof, carbonic acids or salts thereof, oxygen acids of phosphorus, oxygen acids of sulfur, oxygen acids of nitrogen, partial esters or hydrogen salts of these oxygen acids, carbonic acid and its hydrogen salt, sulfonic acids, and carboxylic acids. [0046] Other examples of such biodegradation and decomposition agents include an organic acid selected from the group consisting of oxo acids having 2 to 6 carbon atoms per molecule, saturated dicarboxylic acids having 2 to 6 carbon atoms per molecule, and lower alkyl esters of the oxo acids or the saturated dicarboxylic acids with alcohols having from 1 to 4 carbon atoms. Biodegradation agents may also comprise enzymes such as, for example, a lipase, a cellulase, an esterase, and combinations thereof. Other types of
biodegradation and decomposition agents can include cellulose phosphate, starch phosphate, calcium secondary phosphate, calcium tertiary phosphate, calcium phosphate hydroxide, glycolic acid, lactic acid, citric acid, tartaric acid, malic acid, oxalic acid, malonic acid, succinic acid, succinic anhydride, glutaric acid, acetic acid, and combinations thereof. [0047] Cellulose acetate fibers described herein may also be substantially free of several other types of additives that have been added to other fibers to encourage environmental non-persistence. Examples of these additives can include, but are not limited to, polyesters, including aliphatic and low molecular weight (e.g., less than 5000) polyesters, enzymes, microorganisms, water soluble polymers, modified cellulose acetate, water-dispersible additives, nitrogen-containing compounds, hydroxy-functional compounds, oxygen- containing heterocyclic compounds, sulfur-containing heterocyclic compounds, anhydrides, monoepoxides, and combinations thereof. In some cases, the fibers described herein may include not more than about 0.5, 0.4, 0.3, 0.25, 0.1, 0.075, 0.05, 0.025, 0.01, 0.0075, 0.005, 0.0025, or 0.001 weight percent of these types of additives, or the cellulose acetate fibers may not include any of these types of additives. [0048] Turning back to FIG.1, the dope can be extruded through a plurality of holes in spinneret 102 into a vertical spinning cabinet 104 to form continuous cellulose acetate filaments. At spinneret 102, filaments 103 may be drawn to form a few, tens, hundreds, or even thousands of individual filaments. That is, each spinneret face has more than one cluster of holes to produce a group of filaments, and an individually-entangled cellulosic yarn is produced from each group of filaments. Each of these clusters may include between 2 and 300, 4 and 300, between 8 and 150, between 12 and 75, between 15 and 30 holes, which produces a yarn having the corresponding number of fibers. That is, each group of filaments may include between 2 and 300, 4 and 300, between 8 and 150, between 12 and 75, between 15 and 30 individual fibers. Spinneret 102 may be operated at any speed suitable to produce filaments and bundles having desired size and shape.
[0049] As used herein, “entangle” refers to physically attaching a group of filaments to one another via filament deformation and/or intermingling. In some embodiments of the invention, entangle is in at least one location along the length of the filament, which includes intermittently or continuously entanglement. For example, filaments can be entangled by twisting and/or air jetting. Thus, respective individually-entangled yarns are not entangled with one another. Rather, only the group of filaments in these individually-entangled, or separately-entangled, yarns are entangled with one another. [0050] Individual bundles may be assembled into a filament yarn, as will be described in more detail below. As used herein, a “filament yarn” or “tow yarn” refers to a yarn formed from a plurality of continuous individual filaments. The filament yarn may be of any suitable size and, in some embodiments, may have a total denier between 10 and 3000, between 20 and 500, between 30 and 300, between 40 and 150, or between 50 and 100. [0051] The individual filaments, which are extruded in a generally longitudinally aligned manner and which ultimately form the filament yarn, may also be of any suitable size. For example, each filament may have a linear denier per filament (weight in g of 9000m fiber length) between 0.25 and 50, between 0.5 and 25, between 1 and 10, between 2 and 6, or between 3 and 5, measured according to ASTM D1577-01 using the FAVIMAT vibroscope procedure. As used herein, the term “filament” refers to an elongated, continuous single strand fiber and is distinguished from a staple fiber, which has been cut to a specified length. [0052] The individual filaments discharged from the spinneret may have any suitable transverse cross-sectional shape. Exemplary cross-sectional shapes include, but are not limited to, circular or any shape other than circular (irregular), such as Y-shaped, I-shaped (dog bone), closed C-shaped, tri-lobal, multi-lobal, X-shaped, or crenulated. When a filament has a multi-lobal cross- sectional shape, it may have at least 4, 5, or 6 or more lobes. In some cases, the filaments may be symmetric along one or more, two or more, three or more, or four or more axes, and, in other embodiments, the filaments may be asymmetrical. As used herein, the term “cross-section” generally refers to the
transverse cross-section of the filament relative to the longitudinal axis of the filament. The cross-section of the filament may be determined and measured using Quantitative Image Analysis (QIA). [0053] In some embodiments, the cross-sectional shape of an individual filament may be characterized according to its deviation from a round cross- sectional shape. In some cases, this deviation can be characterized by the shape factor of the filament or fiber, which is determined by the following formula: Shape Factor = Perimeter / (4π x Cross-Sectional Area)1/2. In some embodiments, the shape factor of the individual cellulose acetate (or other cellulose ester) filaments or fibers can be at least about 1, 1.01, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2, 2.25, 2.5, 2.75, 3, or 3.25 and/or not more than about 5, 4.8, 4.75, 4.5, 4.25, 4, 3.75, 3.5, 3.25, 3, 2.75, 2.5, 2.25, 2, 1.75, 1.5, or 1.25. (Note: these values may also be expressed as ratios of the listed numbers to 1 – e.g., 1.45:1). The shape factor of filament or fiber having a round cross-sectional shape is 1. The shape factor can be calculated from the cross-sectional area of a filament or fiber, which can be measured using QIA. [0054] Additionally, the cross-sectional shape of the filament or fiber may also be compared to a round cross-section according to its equivalent diameter, which is the equivalent diameter of a round filament or fiber having a cross- sectional area equal to a given filament or fiber. In some embodiments, cellulose acetate filaments or fibers according to embodiments of the present invention can have an equivalent diameter of at least about 0.0022, 0.0023, 0.0024, 0.0025, 0.0030, 0.0033, 0.0035, 0.0040, 0.0045, 0.0050, 0.0055, 0.0060, 0.0065, 0.0070, 0.0073, 0.0075, 0.0080, 0.0085, 0.0090, 0.0095, 0.0100, 0.0103, 0.0104, 0.0105, 0.0110, 0.0112, 0.0115, 0.0120, 0.0125, 0.0126, 0.013, 0.014, or 0.015 mm. Alternatively, or in addition, the cellulose acetate filaments or fibers may have an equivalent diameter of not more than about 0.0400, 0.0375, 0.036, 0.0359, 0.0350, 0.0033, 0.0327, 0.0325, 0.0300, 0.0275, 0.0250, 0.0232, 0.0225, 0.0200, 0.0179, 0.0175, 0.016, 0.0150, 0.0127, 0.0125, or 0.0120 mm. The equivalent diameter is calculated from the cross-section of a filament or fiber, measured using QIA.
[0055] In another embodiment of the invention, the cross-section of a cellulose acetate fiber is shaped with many lobes. Although not wishing to be bound by theory, after the dope is spun through the spinneret, it can take on a round-shaped cross-section. After rapid evaporation of the solvent from the surface, a skin layer on the surface of the fiber can form. After that, evaporation of the solvent from the inside of the fiber an cause the skin layer to cave in toward the fiber cross-section, giving rise to the final multi-lobal cross-section. In yet another embodiment, the cross-section can be crenulated, which is defined as having an irregularly wavy or serrated outline. [0056] According to some embodiments, the filaments or fibers 103 discharged from cabinet 104 may be at least partially coated with at least one fiber finish by at least one finish applicator 106 to produce coated filaments 107. As used herein, the terms “fiber finish” and “finish” refer to any suitable type of coating that, when applied to a fiber, modifies friction exerted by and on the fiber, and alters the ability of the fibers to move relative to one another and/or relative to a surface. Finishes are not the same as adhesives, bonding agents, or other similar chemical additives which, when added to fibers, prevent movement between the fibers by adhering them to one another. Finishes, when applied, continue to permit the movement of the fibers relative to one another and/or relative to other surfaces, but may modify the ease of this movement by increasing or decreasing the frictional forces. In some cases, finishes may not modify the frictional forces between fibers, but can, instead, impart one or more other desirable properties to the final coated fiber. [0057] In some embodiments, the filaments or yarns may include at least two finishes applied to all or a portion of its surface at one or more points during the fiber production process. In other cases, the fibers may only include one finish while, in other cases, the fibers may not include any finish at all. When two or more finishes are applied to the fibers, the finishes may be applied as a blend of two or more different finishes, or the finishes may be applied separately at different times during the process. For example, in some cases, the fibers may be at least partially coated with a spinning or spin finish applied to the filament yarn at one or more points during the process of forming the fibers. For
example, in some embodiments, the spinning finish may be added to the fiber just after spinning. Alternatively, or in addition, the spinning finish may be added to the filament yarn just prior to subsequent fiber processing, such as texturing or crimping, if applicable. In some cases, no spinning finish may be applied. [0058] Any suitable method of applying the spinning finish may be used and can include, for example, spraying, wick application, dipping, or use of squeeze, lick, or kiss rollers. When used, the spinning finish may be of any suitable type and can be present on the filaments or fibers in an amount of at least about 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.70, 0.80, 0.90, or 1 percent finish-on-yarn (FOY). Alternatively, or in addition, the spinning finish may be present in an amount of not more than about 10.0, 9.0, 8.0, 7.0, 6.0, 5.0, 4.0, 3.0, 2.0,1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.90, 0.80, 0.75, 0.70, 0.65, 0.60, or 0.50 percent finish-on-yarn (FOY) based on the total weight of the dried fiber. As used herein “FOY” or “finish on yarn” refers to the amount of finish on the fiber or filament, yarn less any added water. One or two or more types of spinning finishes may be used. In some cases, the spinning finish may be hydrophobic. [0059] Further, in some embodiments, the top-coat (and/or spinning) finish may include other additives such as, for example, an anti-static agent. In addition, the finish may also include one or more other additives such as a wetting agent, antioxidants, biocides, anti-corrosion agents, pH control agents, emulsifiers, and combinations thereof. It is also possible that one or more additives may be added to a fiber as a coating, but without additional friction- modifying properties. [0060] When present, any suitable anti-static agent may be used and, in some cases, the anti-static agent may include polar and/or hydrophilic compounds. When used, such additives may be present in any suitable amount such as, for example, at least about 0.10, 0.15, 0.20, 0.25, 0.30, or 0.35 weight percent and/or not more than about 3, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1, 0.90, 0.80, 0.70, 0.60, or 0.50 weight percent, based on the total weight of the fiber.
[0061] When the fibers are coated with an anti-static finish, the coated fiber may exhibit a static half-life of not more than about 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 22, 20, 17, 15, 12, 10, 8, 5, 3, 2, 1.5, or 1 second, measured according to AATCC 84-2011. In some embodiments, the fibers may have a static half-life of not more than about 30, 25, 20, 18, 15, 12, 10, or 8 minutes. In other embodiments, the static half-life of the coated fiber may be at least about 30 seconds, at least about 1 minute, at least about 5, 8, 10, 15, 20, 30, 40, 50, 60, 75, 90, or 100 minutes and/or not more than about 120, 110, 100, 90, 75, 60, 45, 40, 35, 30, 20, 15, or 12 minutes, measured according to AATCC 84-2011. [0062] In some embodiments, this may be not more than 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, or 5 percent of the static half- life of an identical but uncoated fiber. In some cases, the static half-life of the coated fiber may be at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95 percent less than the static half-life of an identical but uncoated fiber. [0063] Alternatively, or in addition, the coated fibers described herein may have a surface resistivity (Log R) of at least about 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, or 9 and/or not more than about 11, 10.5, 10, 9.75, 9.5, 9.25, 9, 8.75, 8.5, 8.25, 8, 7.75, 7.5 measured according to AATCC TM76-2011. The surface resistivity was measured using a Monroe Electronics resistivity meter (Model No. 272A) connected to a Keithley Instruments isolation box (Model No. 6104) using an isolation cup for measuring the resistivity of the fibers. The surface resistivity (Log R) is calculated by multiplying the surface resistance by the ratio of the length of the area being tested to its width and expressing the result as the base 10 logarithm of the calculated value. [0064] In some embodiments, the fibers or filament yarns may be at least partially coated with at least one spinning finish and at least one top-coat finish. The total amount of all finishes present on the fibers or filament yarns according to embodiments of the present invention can be at least about 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, 1.0, or 1.05 percent FOY and/or not more than about 10, 9, 8, 7, 6, 5, 4, 3, 2,
1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.90, 0.80, 0.75, 0.70, 0.65, 0.60, 0.55, 0.50, or 0.45 percent FOY, based on the total weight of the dried fiber. The amount of finish on the fibers as expressed by weight percent may be determined by solvent extraction according to ASTM D2257. [0065] In some cases, when the filament yarn is coated with a spinning and/or top-coat finish, the filament yarn may exhibit a fiber-to-fiber (F/F) coefficient of friction (COF) of at least about 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, or 0.40 and/or not more than about 0.55, 0.50, 0.45, 0.42, 0.40, 0.35, 0.33, 0.30, 0.25, 0.20, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, or 0.06. Values for the F/F coefficient of friction (COF) of continuous filaments can be determined according to ASTM D3412 with the specified yarn parameters, a speed of 100 m/min, an input tension of 10 grams, and a single twist applied to the filament. [0066] In another embodiment, yarns described herein may have a F/F coefficient of friction value within one or more of the above ranges measured using a continuous tension tester electronic device (CTT-E) according to ASTM D3412 with the specified yarn parameters, a speed of 20 m/min, an input tension of 10 grams, and a single twist applied to the filament. [0067] Additionally, filament yarns coated with a spinning and/or top-coat finish according to embodiments of the present invention may exhibit a fiber-to- metal (F/M) coefficient of friction of at least about 0.01, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.57, 0.60, or 0.65 and/or not more than about 0.80, 0.75, 0.70, 0.65, 0.60, 0.55, 0.50, 0.45, or 0.40. Values for the F/M coefficient of friction of continuous filaments can be determined according to ASTM D3108 with the specified yarn parameters, a speed of 100m/min, and an input tension of 48 grams. [0068] In another embodiment, yarns described herein may have a F/M coefficient of friction value within one or more of the above ranges measured using a continuous tension tester electronic device (CTT-E) according to ASTM D3108 with the specified yarn parameters, a speed of 100 m/min, and an input tension of 10 grams.
[0069] The coated fibers as described herein may also exhibit higher-than- expected strength. For example, in some embodiments, the coated fibers may be formed from filaments that exhibit a tenacity of at least about 0.5, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, 1.0, 1.05, 1.1, 1.15, 1.20, 1.25, 1.30, or 1.35 grams-force/denier (g/denier) and/or not more than 2.50, 2.45, 2.40, 2.35, 2.30, 2.25, 2.20, 2.15, 2.10, 2.05, 2.00, 1.95, 1.90, 1.85, 1.80, 1.75, 1.70, 1.65, 1.60, 1.55, 1.50, 1.47, 1.45, or 1.40 g/denier, and/or between 0.5 and 3.0, between 1 and 2, or between 1.25 and 1.5 g/denier, as measured according to ASTM D3822. Additionally, in some embodiments, the elongation at break of the coated fibers can be at least about 5, 6, 10, 15, 20, or 25 percent and/or not more than about 50, 45, 40, 35, or 30 percent, and/or between 5 and 50, between 10 and 40, or between 20 and 30, as measured according to ASTM D3822. [0070] In one embodiment, fibers and filament yarns described herein include little or no plasticizer and have unexpectedly been shown to exhibit enhanced biodegradability under industrial, home, and soil conditions, even as compared to cellulose acetate fibers with higher levels of plasticizer. [0071] In some embodiments, the fibers described herein can include less than about 50, 30, 27, 25, 22, 20, 17, 15, 12, 10, 9.5, 9, 8.5, 8, 7.5, 7, 6.5, 6, 5.5, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5, 0.25, or 0.10 percent plasticizers, based on the total weight of the fiber and/or yarns, or the fibers may include no plasticizer. When present, the plasticizer may be incorporated into the fiber itself by being blended with the solvent dope or cellulose acetate flake, or the plasticizer may be applied to the surface of the fiber or filament by spraying, by centrifugal force from a rotating drum apparatus, or by an immersion bath. [0072] Examples of plasticizers that may or may not be present in or on the fibers can include, but are not limited to, aromatic polycarboxylic acid esters, aliphatic polycarboxylic acid esters, lower fatty acid esters of polyhydric alcohols, and phosphoric acid esters. Further examples can include, but are not limited to, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, dimethoxyethyl phthalate, ethyl phthalylethyl glycolate, butyl phthalylbutyl glycolate, tetraoctyl pyromellitate, trioctyl
trimellitate, dibutyl adipate, dioctyl adipate, dibutyl sebacate, dioctyl sebacate, diethyl azelate, dibutyl azelate, dioctyl azelate, glycerol, trimethylolpropane, pentaerythritol, sorbitol, glycerin triacetate (triacetin), diglycerin tetracetate, triethyl phosphate, tributyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, and tricresyl phosphate, and combinations thereof. In some embodiments, the fibers of the present invention may not include any type of plasticizer or other additive, and can consist essentially of, or consist of, cellulose acetate and not more than 1 percent FOY of a spinning finish. [0073] Additionally, the cellulose acetate fibers described herein may not have undergone additional treatment steps designed to enhance the biodegradability of the fibers. For example, the fibers may not have been hydroylzed or treated with enyzmes or microorganisms. The fibers may include not more than about 1, 0.75, 0.5, 0.25, 0.1, 0.05, or 0.01 weight percent of an adhesive or bonding agent and may include less than 1, 0.75, 0.5, 0.25, 0.1, 0.05, or 0.01 weight percent of modified or substituted cellulose acetate. In some embodiments, the fibers may not include any adhesive or bonding agent and may not be formed from any substituted or modified cellulose acetate. Substituted or modified cellulose acetate may include cellulose acetate that has been modified with a polar substituent, such as a substituent selected from the group consisting of sulfates, phosphates, borates, carbonates, and combinations thereof. [0074] In one embodiment, after the finish is applied, the cellulose acetate fibers are passed through at least one entanglement (TF) jet or discharged from at least one entanglement nozzle 108. The TF jets expose the cellulose acetate fibers to turbulent air such that one or more nodes are formed along the length of the yarn. Formation of these nodes helps with spinning, weaving, and processability of the yarn. In one embodiment or in combination with any other mentioned embodiments, the TF jets may be blown at a pressure between 10 and 20 pounds per square inch (psi). In one embodiment or in combination with any other mentioned embodiments, the yarn has an entanglement node density within a range between 1 and 50, between 2 and 30, between 4 and 20, or between 6 and 15 nodes per foot.
[0075] In some embodiments, the resulting individually-entangled yarns formed from the cellulose acetate fibers have a moisture content within a range between 3.5 and 30 percent, 3.5 and 25 percent, 3.5 and 20 percent, 3.5 and 15 percent, 4 and 10 percent, 4 and 8 percent, or 5 and 7 percent based on the total weight of the yarn. Additionally or alternatively, in some embodiments, the resulting individually-entangled yarns formed from the cellulose acetate fibers have a residual solvent content within a range between 0 and 30 percent, between 2 and 20 percent, or between 4 and 15 percent based on the total weight of the yarn. [0076] In some embodiments, after the entanglement, the resulting individually-entangled yarns 109 are routed, via at least one yarn guide 110, towards at least one winder 112. As will be described in more detail below, the newly-formed yarns may be accumulated onto cores or tubes and the cores or tubes may be removable from winders 112, with the resulting individually- entangled yarns wound around the cores or tubes, as individual yarn packages of cellulosic material. [0077] Referring now to FIGS. 2-10, yarn guide 110 receives a plurality of individually-entangled yarns 109 entangled by entanglement nozzle 108 (shown in FIG.1), and then routes yarns 109 towards winders 112 to produce one or more yarn packages. Specifically, each yarn guide 110 includes a guide arm 116 that is individually capable of routing one or more yarns 109 towards winders 112. Each winder 112 includes a rotatable spool 118, and at least one core 120 is removably coupled to and rotatable with rotatable spool 118 such that yarns 109 may be wound or co-wound thereon. As will be described in more detail below, each spool 118 may receive more than one core 120 thereon. Thus, a plurality of individually-entangled yarns 109 may be wound around each common core 120. In one embodiment or in combination with any other mentioned embodiments, the number of yarns wound or co-wound on core 120 is not more than 20, not more than 15, not more than 10, not more than 5, or not more than 4. [0078] As used herein, “co-wound” refers to the winding of more than one yarn around a common core at the same time.
[0079] As described above, spinnerets 102 (shown in FIG.1) are modified to output more than one distinct filament grouping that each produces an individually-entangled yarn 109. Thus, in one embodiment or in combination with any other mentioned embodiments, yarns 109 derived from the same spinneret. [0080] In one embodiment or in combination with any other mentioned embodiments, core 120 has a substantially cylindrical shape. In other words, core 120 does not include flanges, or any other structure that provides lateral support to yarns wound on core 120, defined at terminal ends of core 120. [0081] In one embodiment or in combination with any other mentioned embodiments, core 120 has a length between 2 and 24, between 4 and 12, or between 5 and 8 inches. [0082] In one embodiment or in combination with any other mentioned embodiments, core 120 is made of a non-metallic material. Exemplary non- metallic materials can include a cardboard material and/or a plastic material. [0083] In one embodiment, two individually-entangled yarns 109 are wound around a common spool 118, which may have one or more cores 120 positioned thereon. One or more yarn sections may be formed on each core 120, and each yarn section can include one or more individually-entangled yarns co-wound around core 120. These yarns 109 are not twisted with each other on core 120. That is, even when more than one yarn 109 is routed towards a winder 112 from a single guide arm 116, these yarns 109 are combined and co-wound on at least one common section of core 120 without being twisted or entangled with one another before reaching the winder 112. Thus, the respective yarns 109 are unwindable from core 120 individually. [0084] As used herein, “unwound individually,” “unwindable individually,” and variations thereof means yarns can be simultaneously and/or sequentially unwound from their core and separated from one another. As used herein, “unwound simultaneously,” “unwindable simultaneously,” and variations thereof means yarns can be simultaneously unwound from their core and separated from one another. As used herein, “unwound sequentially,” “unwindable
sequentially,” means one yarn can be unwound from the core without unwinding another yarn from the same core. [0085] In one embodiment or in combination with any other mentioned embodiments, each yarn section may have an individual weight of less than 10 pounds, less than 8 pounds, less than 6 pounds, less than 5 pounds, less than 4 pounds, or less than 2 pounds. [0086] Referring specifically to FIGS.2, 3, and 4, a first guide arm 122 routes a first yarn 124 towards a first core 126 on a first spool 127, a second guide arm 128 routes a second yarn 130 towards a second core 129 on first spool 127, a third guide arm 132 routes a third yarn 134 towards a third core 131 on a second spool 133, and a fourth guide arm 138 routes a fourth yarn 140 towards a fourth core 135 on second spool 133. Thus, yarns 124, 130, 134, and 140 are wound around their respective cores 126, 129, 131, and 135 to produce four yarn packages 142 simultaneously. [0087] Referring to FIGS.3 and 4, first spool 127 having two yarn packages 142 formed thereon is illustrated. For example, one yarn package 142 includes first core 126 and a first yarn section 144 formed from first yarn 124, and another yarn package 142 includes second core 129 and a second yarn section 146 formed from second yarn 130. Thus, each yarn package 142 is individually removable from first spool 127. For example, yarn package 142 associated with first core 126 may be removed, and then yarn package 142 associated with second core 129 may be removed afterwards. Accordingly, the package sections have a reduced size and weight, which may enhance the processability of yarn 109 wound thereon. [0088] Referring to FIGS.3A and 4A, in some embodiments, yarns 124 and 130 are wound around a common core 120 to form yarn sections 144 and 146 thereon that are similar to those illustrated in FIGS.3 and 4. Specifically with reference to FIG.3A, such a multi-section yarn package 137 may include yarn sections 144 and 146 spaced from one another on the common core 120. Alternatively, and with reference to FIG.4A, such a multi-section yarn package 139 may include yarn sections 144 and 146 adjacent to and in substantial
contact with one another on the common core to enhance the stability of the yarn package 139. [0089] As used herein, a “separate section” of the core is defined between two parallel planes extending perpendicular to the longitudinal axis of the core. [0090] Referring now to FIGS.5 and 6, in one embodiment, first guide arm 122 routes first yarn 124 towards first core 126, second guide arm 128 routes second yarn 130 towards first core 126, third guide arm 132 routes third yarn 134 towards second core 129, and fourth guide arm 138 routes fourth yarn 140 towards second core 129. Yarns 124 and 130 are wound around separate sections of first core 126, and yarns 134 and 140 are wound around separate sections of second core 129 to produce two multi-section yarn packages 150. For example, referring to FIG.6, one yarn package 150 includes first core 126, a first yarn section 152 formed from first yarn 124, and a second yarn section 154 formed from second yarn 130. The other yarn package 150 includes second core 129, a third yarn section 156 formed from third yarn 134, and a fourth yarn section 158 formed from fourth yarn 140. Yarn sections 152, 154, 156, and 158 may be spaced from one another, or may be adjacent to and in substantial contact with one another, on their respective cores 126 and 129. [0091] Referring to FIG. 6A, in one embodiment, yarns 124, 130, 134, and 140 may be wound around a common core 120 to form yarn sections 152, 154, 156, and 158 thereon that are similar to those illustrated in FIG.6. Such a multi- section yarn package 155 may include yarn sections 152, 154, 156, and 158 spaced from one another on the common core 120. Alternatively, multi-section yarn package 155 may include yarn sections 152, 154, 156, and 158 adjacent to and in substantial contact with one another on the common core 120 to enhance the stability of the yarn package 155. [0092] Thus, yarns 109 are wound around separate sections of first core 126 and second core 129, or the common core 120, to increase the winding capacity of cabinet 104 (shown in FIG.1) while still enabling yarns 109 to be unwound from the cores individually. [0093] Referring now to FIGS.7 and 8, in one embodiment, first guide arm 122 routes first yarn 124 and second yarn 130 towards a fifth core 157, and
second guide arm 128 routes third yarn 134 and fourth yarn 140 towards a sixth core 159. Specifically, the yarn pairs are combined at the respective guide arms 122 and 128, but are not twisted or not permanently entangled before being wound on the respective cores 157 and 159. Accordingly, the yarn pairs define a combined yarn 160 that is wound around the respective cores 157 and 159 to enable two yarn packages 162 to be produced simultaneously. For example, referring to FIG. 8, yarn package 162 includes combined yarn 160 wound around at least one common section of first core 157. In one embodiment, combined yarn 160 is co-wound around core 157 along the length thereof. Accordingly, yarn package 162 has a single yarn section wound thereon formed from more than one yarn. [0094] As used herein, “combined” refers to two or more yarns occupying at least one common section of a core. Combined yarns are capable of being individually unwound from a core (i.e., unwound at the same time, but not sequentially, as separate yarns). [0095] Referring now to FIGS.9 and 10, in one embodiment, first guide arm 122 routes first yarn 124 and second yarn 130 towards first core 126, and second guide arm 128 routes third yarn 134 and fourth yarn 140 towards second core 129. Specifically, the yarn pairs are combined at the respective guide arms 122 and 128, but are not twisted or not permanently entangled before being wound on first core 126. The yarn pairs define combined yarns 164 and 166 that are wound around the respective cores 126 and 129 to produce multiple yarn packages 168 simultaneously. For example, referring to FIG.10, one yarn package 168 includes first core 126 and a first yarn section 170 formed from combined yarn 164, and the other yarn package 168 includes second core 129 and a second yarn section 172 formed from combined yarn 166. Accordingly, each yarn package 168 has a yarn section wound thereon that is formed from more than one yarn (i.e., a combined yarn). [0096] Referring to FIG. 10A, in one embodiment, yarns 164 and 166 are wound around a common core 120 to form yarn sections 170 and 172 thereon that are similar to those illustrated in FIG. 10. Similar to the embodiments illustrated in FIGS.3 and 4, yarn sections 170 and 172 may be spaced from
one another on the common core 120, or may be adjacent to and in substantial contact with one another on the common core to define a multi-section yarn package 173. [0097] The above embodiments are for example purposes only. The systems and methods described herein may be used to produce yarn packages having any number of yarns, combined yarns, and/or yarn sections. [0098] In one embodiment or in combination with any other mentioned embodiments, yarns 109 are wound around a respective core 120 in a helical pattern. For example, each core may have a longitudinal axis 174, and yarns 109 may be wound on the core at an angle between 0.1 and 89.9, between 1 and 30, between 2 and 20, or between 5 and 12 degrees relative to longitudinal axis 174. Accordingly, yarn may be collected along the length of the core. [0099] In one embodiment or in combination with any other mentioned embodiments, the yarn packages produced as described above may have a combined weight, including at least the core and yarn wound thereon, between 1 and 40, between 2 and 3, between 4 and 20, or between 5 and 15 pounds. [00100] In one embodiment or in combination with any other mentioned embodiments, each wound yarn section has a width, as defined relative to longitudinal axis 174, between 1 and 8 inches, between 1.5 and 6 inches, or between 2 and 3 inches on the core. [00101] Cellulose acetate fibers, filaments, and/or yarns as described herein can be used to form woven and/or nonwoven webs that can be used in several types of fibrous articles. For example, in some cases, coated fibers as described herein may be suitable for use in forming fabrics that exhibit unexpected and improved properties, such as strength, durability, flexibility, softness, and absorbency. Additionally, the fibers as described herein exhibit unique properties such as lower friction, higher strength, and more durability, which facilitate faster, more efficient, and more uniform processing of the fibers into webs. [00102] Further, it has been found that cellulose acetate fibers as described herein exhibit enhanced levels of environmental non-persistence, characterized by better-than-expected degradation under various environmental conditions.
Fibers and fibrous articles described herein may meet or exceed passing standards set by international test methods and authorities for industrial compostability, home compostability, and/or soil biodegradability. [00103] To be considered “compostable,” a material must meet the following four criteria: (1) the material must be biodegradable; (2) the material must be disintegrable; (3) the material must not contain more than a maximum amount of heavy metals; and (4) the material must not be ecotoxic. [00104] As used herein, the term “biodegradable” generally refers to the tendency of a material to chemically decompose under certain environmental conditions. Biodegradability is an intrinsic property of the material itself, and the material can exhibit different degrees of biodegradability, depending on the specific conditions to which it is exposed. The term “disintegrable” refers to the tendency of a material to physically decompose into smaller fragments when exposed to certain conditions. Disintegration depends both on the material itself, as well as the physical size and configuration of the article being tested. Ecotoxicity measures the impact of the material on plant life, and the heavy metal content of the material is determined according to the procedures laid out in the standard test method. [00105] The cellulose acetate fibers can exhibit a biodegradation of at least 70 percent in a period of not more than 50 days, when tested under aerobic composting conditions at ambient temperature (28°C ± 2°C) according to ISO 14855-1 (2012). In some cases, the cellulose acetate fibers can exhibit a biodegradation of at least 70 percent in a period of not more than 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, or 37 days when tested under these conditions, also called “home composting conditions.” These conditions may not be aqueous or anaerobic. In some cases, the cellulose acetate fibers can exhibit a total biodegradation of at least about 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, or 88 percent, when tested under according to ISO 14855-1 (2012) for a period of 50 days under home composting conditions. This may represent a relative biodegradation of at least about 95, 97, 99, 100, 101, 102, or 103 percent, when compared to cellulose subjected to identical test conditions.
[00106] To be considered “biodegradable,” under home composting conditions according to the French norm NF T 51-800 and the Australian standard AS 5810, a material must exhibit a biodegradation of at least 90 percent in total (e.g., as compared to the initial sample), or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item. The maximum test duration for biodegradation under home compositing conditions is 1 year. The cellulose acetate fibers as described herein may exhibit a biodegradation of at least 90 percent within not more than 1 year, measured according 14855-1 (2012) under home composting conditions. In some cases, the cellulose acetate fibers may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 1 year, or the fibers may exhibit 100 percent biodegradation within not more than 1 year, measured according 14855-1 (2012) under home composting conditions. [00107] Additionally, or in the alternative, the fibers described herein may exhibit a biodegradation of at least 90 percent within not more than about 350, 325, 300, 275, 250, 225, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 90, 80, 70, 60, or 50 days, measured according 14855-1 (2012) under home composting conditions. In some cases, the fibers can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 70, 65, 60, or 50 days of testing according to ISO 14855-1 (2012) under home composting conditions. As a result, the cellulose acetate fibers may be considered biodegradable according to, for example, French Standard NF T 51-800 and Australian Standard AS 5810 when tested under home composting conditions. [00108] The cellulose acetate fibers can exhibit a biodegradation of at least 60 percent in a period of not more than 45 days, when tested under aerobic composting conditions at a temperature of 58°C (± 2°C) according to ISO 14855-1 (2012). In some cases, the fibers can exhibit a biodegradation of at least 60 percent in a period of not more than 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, or 27 days when tested under these conditions, also called “industrial composting conditions.” These may not be aqueous or
anaerobic conditions. In some cases, the fibers can exhibit a total biodegradation of at least about 65, 70, 75, 80, 85, 87, 88, 89, 90, 91, 92, 93, 94, or 95 percent, when tested under according to ISO 14855-1 (2012) for a period of 45 days under industrial composting conditions. This may represent a relative biodegradation of at least about 95, 97, 99, 100, 102, 105, 107, 110, 112, 115, 117, or 119 percent, when compared to cellulose fibers subjected to identical test conditions. [00109] To be considered “biodegradable,” under industrial composting conditions according to ASTM D6400 and ISO 17088, at least 90 percent of the organic carbon in the whole item (or for each constituent present in an amount of more than 1% by dry mass) must be converted to carbon dioxide by the end of the test period when compared to the control or in absolute. According to European standard ED 13432 (2000), a material must exhibit a biodegradation of at least 90 percent in total, or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item. The maximum test duration for biodegradability under industrial compositing conditions is 180 days. The cellulose acetate fibers described herein may exhibit a biodegradation of at least 90 percent within not more than 180 days, measured according 14855-1 (2012) under industrial composting conditions. In some cases, the cellulose acetate fibers may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 180 days, or the fibers may exhibit 100 percent biodegradation within not more than 180 days, measured according 14855-1 (2012) under industrial composting conditions. [00110] Additionally, or in the alternative, cellulose acetate fibers described herein may exhibit a biodegradation of least 90 percent within not more than about 175, 170, 165, 160, 155, 150, 145, 140, 135, 130, 125, 120, 115, 110, 105, 100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, or 45 days, measured according 14855-1 (2012) under industrial composting conditions. In some cases, the cellulose acetate fibers can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 65, 60, 55, 50, or 45 days of testing according to ISO 14855-1 (2012) under industrial composting conditions. As a
result, the cellulose acetate fibers described herein may be considered biodegradable according ASTM D6400 and ISO 17088 when tested under industrial composting conditions. [00111] The fibers or fibrous articles may exhibit a biodegradation in soil of at least 60 percent within not more than 130 days, measured according to ISO 17556 (2012) under aerobic conditions at ambient temperature. In some cases, the fibers can exhibit a biodegradation of at least 60 percent in a period of not more than 130, 120, 110, 100, 90, 80, or 75 days when tested under these conditions, also called “soil composting conditions.” These may not be aqueous or anaerobic conditions. In some cases, the fibers can exhibit a total biodegradation of at least about 65, 70, 72, 75, 77, 80, 82, or 85 percent, when tested under according to ISO 17556 (2012) for a period of 195 days under soil composting conditions. This may represent a relative biodegradation of at least about 70, 75, 80, 85, 90, or 95 percent, when compared to cellulose fibers subjected to identical test conditions. [00112] In order to be considered “biodegradable,” under soil composting conditions according the OK biodegradable SOIL conformity mark of Vinçotte and the DIN Geprüft Biodegradable in soil certification scheme of DIN CERTCO, a material must exhibit a biodegradation of at least 90 percent in total (e.g., as compared to the initial sample), or a biodegradation of at least 90 percent of the maximum degradation of a suitable reference material after a plateau has been reached for both the reference and test item. The maximum test duration for biodegradability under soil compositing conditions is 2 years. The cellulose acetate fibers as described herein may exhibit a biodegradation of at least 90 percent within not more than 2 years, 1.75 years, 1 year, 9 months, or 6 months measured according ISO 17556 (2012) under soil composting conditions. In some cases, the cellulose acetate fibers may exhibit a biodegradation of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent within not more than 2 years, or the fibers may exhibit 100 percent biodegradation within not more than 2 years, measured according ISO 17556 (2012) under soil composting conditions.
[00113] Additionally, or in the alternative, cellulose acetate fibers described herein may exhibit a biodegradation of at least 90 percent within not more than about 700, 650, 600, 550, 500, 450, 400, 350, 300, 275, 250, 240, 230, 220, 210, 200, or 195 days, measured according 17556 (2012) under soil composting conditions. In some cases, the cellulose acetate fibers can be at least about 97, 98, 99, or 99.5 percent biodegradable within not more than about 225, 220, 215, 210, 205, 200, or 195 days of testing according to ISO 17556 (2012) under soil composting conditions. As a result, the cellulose acetate fibers described herein may meet the requirements to receive The OK biodegradable SOIL conformity mark of Vinçotte and to meet the standards of the DIN Geprüft Biodegradable in soil certification scheme of DIN CERTCO. [00114] In some embodiments, the cellulose acetate fibers or fibrous articles may include less than 1, 0.75, 0.50, or 0.25 weight percent of components of unknown biodegradability. In some cases, the fibers or fibrous articles described herein may include no components of unknown biodegradability. [00115] In some cases, the cellulose acetate fibers and fibrous articles described herein may have a volatile solids concentration, heavy metals and fluorine content that fulfill all of the requirements laid out by EN 13432 (2000). Additionally, the cellulose acetate fibers may not cause a negative effect on compost quality (including chemical parameters and ecotoxicity tests). [00116] In some cases, the cellulose acetate fibers or fibrous articles can exhibit a disintegration of at least 90 percent within not more than 26 weeks, measured according to ISO 16929 (2013) under industrial composting conditions. In some cases, the fibers or fibrous articles may exhibit a disintegration of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent under industrial composting conditions within not more than 26 weeks, or the fibers or articles may be 100 percent disintegrated under industrial composting conditions within not more than 26 weeks. Alternatively, or in addition, the fibers or articles may exhibit a disintegration of at least 90 percent under industrial compositing conditions within not more than about 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, or 10 weeks, measured according to ISO 16929 (2013). In some cases, the cellulose acetate fibers or fibrous articles
described herein may be at least 97, 98, 99, or 99.5 percent disintegrated within not more than 12, 11, 10, 9, or 8 weeks under industrial composting conditions, measured according to ISO 16929 (2013). [00117] In some cases, the cellulose acetate fibers or fibrous articles can exhibit a disintegration of at least 90 percent within not more than 26 weeks, measured according to ISO 16929 (2013) under home composting conditions. In some cases, the fibers or fibrous articles may exhibit a disintegration of at least about 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5 percent under home composting conditions within not more than 26 weeks, or the fibers or articles may be 100 percent disintegrated under home composting conditions within not more than 26 weeks. Alternatively, or in addition, the fibers or articles may exhibit a disintegration of at least 90 percent within not more than about 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, or 15 weeks under home composting conditions, measured according to ISO 16929 (2013). In some cases, the cellulose acetate fibers or fibrous articles described herein may be at least 97, 98, 99, or 99.5 percent disintegrated within not more than 20, 19, 18, 17, 16, 15, 14, 13, or 12 weeks, measured under home composting conditions according to ISO 16929 (2013). [00118] The cellulose acetate fibers may be used to form textiles for agricultural, medical, food, and other applications, for example. In some embodiments, the textile fabric can be prepared from yams, as described herein. As used herein, textile fabrics are materials made from yams and that are either woven, knitted, crocheted, knotted, embroidered, braided/plaited, laced, or carpet piled. Textile fabrics can include geotextile fabrics, carpet pilings, and fabrics (which includes cloth). The geotextile fabrics as used in the context of a textile fabric herein are those that are woven or knitted. Examples of suitable types of textile fabrics formable from the cellulose acetate fibers can include, but are not limited to, clothing (undergarments, socks, hats, shirts, pants, dresses, scarves, gloves, etc.), bags, baskets, upholstered furnishings, window shades, towels, table cloths, bed coverings, flat surface coverings, in art work, filters, flags, backpacks, tents, handkerchiefs, rags, balloons, kites, sails, parachutes, automotive upholstery, protective clothing such as against
heat for firefighters and welders, protective clothing for bullet armor or stab protection, medical textile fabrics such as implants, and agrotextile fabrics for crop protection. [00119] Referring now to FIGS. 11-13, yarn production system 100 further includes at least one dope mixer 176 and a solvent recovery system 178. In the example embodiments, dope mixer 176 receives fresh solvent 179 and/or solvent 180 from solvent recovery system 178, and receives solids 182, such as the cellulose acetate flake described above. Dope mixer 176 dissolves solids 182 in solvent 180 to produce a dope mixture 184. In some embodiments, dope mixture 184 has between about 15 and 40 percent dissolved solids, and between about 60 and 85 percent solvent, by weight of dope mixture 184. [00120] Dope mixture 184 is then provided to spinnerets 102 in a common cabinet 104 to produce cellulose acetate filaments 103 therefrom. In some embodiments, spinnerets 102 can spin dope mixture 184 at a rate of between 200 and 2000, between 250 and 1000, or between 300 and 500 meters per minute when forming filaments 103. The spinning rate is determined by the surface speed of the godet. In addition, the dope temperature at the outlet of spinnerets 102 may be maintained at between 30 and 120, between 40 and 100, or between 50 and 75 °C during the spinning. These process conditions enable continuous filaments as described herein to be produced for forming into continuous yarn. [00121] For example, as illustrated in FIG. 11, two single-cluster spinnerets 186 spin dope mixture 184 to form filaments 103 therefrom. Specifically, each spinneret 186 forms a group of filaments, such that a first group 188 and a second group 190 of filaments are formed and passed through common cabinet 104. In some embodiments, cabinet 104 further includes an air inlet 192 and an air outlet 194. Air inlet 192 receives a stream of air 196, which is channeled through cabinet 104 as first and second groups 188 and 190 of filaments are passed through cabinet 104. Air 196 is passed by the filaments to remove at least a portion of the solvent therefrom. In some embodiments, first and second groups 188 and 190 of filaments are passed through cabinet for a residence time of between about 0.1 and 2.0 seconds. The residence time is selected to
remove a desired amount of solvent from filaments 103. The removed solvent entrained in air may then be discharged from outlet 194 in the form of an air- solvent stream 198. Air-solvent stream 198 may then be provided to solvent recovery system 178 to recover solvent therefrom. The recovered solvent may then be recycled towards dope mixer 176 to enable additional filaments to be formed therefrom. [00122] In the example embodiments, filaments 103 discharged from cabinet 104 are routed towards finish applicator 106 to apply a finish to filaments 103. In some embodiments, yarn production system 100 includes a first finish applicator 200 and a second finish applicator 202 positioned at separate locations outside cabinet 104. For example, first finish applicator 200 applies a finish to first group 188 of filaments at a first location, and second finish applicator 202 applies a finish to second group 190 of filaments at a second location that is positioned a distance from the first location. Thus, this arrangement of finish applicators 106 facilitates the production of distinct yarns from the respective groups of filaments. [00123] In some embodiments, the finish is applied to filaments 103 before being entangled into yarns. For example, coated filaments 107 routed from finish applicators 200 and 202 may be entangled by entanglement nozzles 108. In the example embodiment, filaments 107 are entangled by air jets discharged from nozzles 108 to produce, for example, first yarn 124 and second yarn 130. For example, a first nozzle 204 at a first location entangles filaments 103 to produce first yarn 124, and a second nozzle 206 at a second location entangles filaments 103 to produce second yarn 130. The first and second locations are positioned a distance from each other to facilitate the production of distinct yarns from the respective groups of filaments. [00124] In some embodiments, first and second yarns 124 and 130 may, optionally, be routed on a godet roll 208 before being received at winders 112. Godet roll 208 may be either located upstream of entanglement nozzles 108, or may be located between entanglement nozzles 108 and winders 112. Godet roll 208 is rotatable at a controlled speeds to facilitate stretching first and/or second yarns 124 and 130 wound thereabout. For example, godet roll 208 is
rotatable to moderate the tension on first and/or second yarns 124 and 130 from the pulling force provided by winders 112. In some embodiments, godet roll 208 and/or winders 112 are operable to stretch yarns 124 and 130 to a draw ratio of less than 2 to 0.8, 1.7 to 0.8, 1.5 to 0.8, 1.3 to 0.81.2 to 0.8, 1 to 0.8, 2 to 1, 1.7 to 1, 1.5 to 1, 1.3 to 1, 1.2 to 1, 1.1 to 1 and 1.1 to 1. [00125] The individually-entangled yarns 124 and 130 are then routed towards yarn guides 110 and winders 112 as described above to produce cellulosic yarn packages, such as those illustrated in FIGS.3, 4, and 8. Although yarns 124 and 130 are illustrated as being combined on godet roll 208, it should be understood that separation between yarns 124 and 130 is maintained prior to and/or during winding around the at least one core. [00126] Referring now to FIG.12, yarn production system 100 includes two multi-cluster spinnerets 210 within common cabinet 104. Spinnerets 210 spin dope mixture 184 to form filaments 103 therefrom. Specifically, each spinneret 210 forms two distinct groups of filaments, such that a first group 212 and a second group 214 of filaments are formed by one spinneret 210, and a third group 216 and a fourth group 218 of filaments are formed by the other spinneret 210. [00127] Each group 212, 214, 216, and 218 passed through common cabinet 104 may then be routed towards finish applicator 106 to apply a finish to filaments 103. In some embodiments, yarn production system 100 includes a first finish applicator 220, a second finish applicator 222, a third finish applicator 224, and a fourth finish applicator 226 each positioned at separate locations outside cabinet 104. For example, first finish applicator 220 applies a finish to first group 212 of filaments at a first location, second finish applicator 222 applies a finish to second group 214 of filaments at a second location, third finish applicator 224 applies a finish to third group 216 of filaments at a third location, and fourth finish applicator 226 applies a finish to fourth group 218 of filaments at a fourth location. Each respective location is positioned a distance from each of the other locations. Thus, this arrangement of finish applicators 106 facilitates the production of distinct yarns from the respective groups of filaments.
[00128] Coated filaments 107 routed from finish applicators 220, 222, 224, and 226 may then be entangled by entanglement nozzles 108. In the example embodiment, filaments 107 are entangled by air jets discharged from nozzles 108 to produce, for example, first yarn 124, second yarn 130, third yarn 134, and fourth yarn 140. For example, a first nozzle 228 at a first location entangles first group 212 of filaments to produce first yarn 124, a second nozzle 230 at a second location entangles second group 214 of filaments to produce second yarn 130, a third nozzle 232 at a third location entangles third group 216 of filaments to produce third yarn 134, and a fourth nozzle 234 at a fourth location entangles fourth group 218 of filaments to produce fourth yarn 140. Each respective location is positioned a distance from each of the other locations. Thus, this arrangement of nozzles 108 facilitates the production of distinct and individually-entangled yarns from the respective groups of filaments. [00129] Yarns 124, 130, 134, and 140 may then be routed towards godet roll 208 for optional further processing of the yarns, as described above. The individually-entangled yarns 124, 130, 134, and 140 may then be routed towards yarn guides 110 and winders 112 as described above to produce cellulosic yarn packages, such as those illustrated in FIGS.6 and 10. [00130] Referring now to FIG.13, yarn production system 100 includes two single-cluster spinnerets 186 within common cabinet 104. Yarn production system 100 also includes a first dope mixer 236 and a second dope mixer 238. Both dope mixers 236 and 238 receive solvent 180 from solvent recovery system 178, for example. In addition, first dope mixer 236 receives first solids 240 to form a first dope mixture 242, and second dope mixer 238 receives second solids 244 to form a second dope mixture 246. First and second solids 240 and 244 may both include cellulose acetate flake as described above. However, first and second dope mixtures 242 and 246 may be different from one another in terms of composition based on any of the variables disclosed herein. Accordingly, one spinneret 186 may spin first dope mixture 242 to produce first yarn 124, and the other spinneret 186 may spin second dope mixture 246 to produce second yarn 130 made of a different material than first yarn 124.
[00131] The individually-entangled yarns 124 and 130 may then be routed towards yarn guides 110 and winders 112 as described above to produce cellulosic yarn packages, such as those illustrated in FIGS.3, 4, and 8, having yarn sections of different material wound thereon. [00132] Referring now to FIGS.14-19, yarns of the cellulosic yarn packages described above may be unwound from their cores, and then rewound onto one or more different cores mounted on a common shaft. The rewinding process produces yarn packages designed to meet criteria associated with subsequent processing of the yarns. Example criteria includes, but is not limited to, physical dimensions of a rewinding core and/or overall package size. For example, the core of the rewind package may have a smaller diameter or a larger diameter than the at least one core of the feed package. The overall package size may be determined based on the weight of the package, the volume of yarn in the package, and/or the length of yarn in the package. [00133] Thus, FIG.14 illustrates an example yarn rewinding system 248 that may be used to rewind yarns 109 from a feed package 250 onto a rewind package 252. Specifically, feed package 250 includes at least one core 120 and yarn 109 wound thereon, such as in any of the package configurations described above. Yarn 109 unwound from feed package 250 is processed by yarn rewinding system 248 and then rewound onto at least one core 254 to produce one or more rewind packages 252. System 248 optionally includes at least one yarn guide 256 and at least one godet roll 258, and also includes at least one finish applicator 260, at least one entanglement nozzle 262, and at least one tension controller 264. A facility may include multiple systems 248 to facilitate the production of multiple rewind packages 252 from multiple feed packages 250. [00134] Yarn guide 256 is similar to yarn guide 110 (shown in FIG. 1), and may be used to facilitate re-routing yarn 109 towards one or more rewind packages 252. Godet roll 258 is similar to godet roll 208 (shown in FIG.11), and may be used to moderate the tension on yarns 109 as they are unwound. Finish applicator 260 is similar to finish applicator 106, and may be used to apply a finish, as described above, to yarns 109 as they are unwound.
Entanglement nozzle 262 is similar to entanglement nozzle 108 (shown in FIG. 1), and may be used to reapply entanglement to yarns 109, which may become at least partially unentangled from the unwinding thereof. The finish may be applied prior to or following re-entanglement of yarns 109 by entanglement nozzle 262. In some embodiments, the finish is applied prior to re-entanglement of yarns 109 to improve the efficiency of the entanglement process. [00135] In general, yarns formed from cellulose acetate material have a relatively low tenacity and weak entanglement in comparison to some other yarn types. Accordingly, tension controller 264 may be used to control the tension in yarns 109 during the rewinding process to limit breakage of the yarns and to maintain entanglement of the yarns during rewinding. For example, in operation, tension controller 264 monitors the tension in unwound yarns 109 as they are routed from feed package 250 to rewind package 252. In some embodiments, tension controller 264 is communicatively coupled with at least one of feed package 250, rewind package 252, or godet roll 258 (when in use) to control the operation thereof. That is, tension controller 264 is operable to adjust the rotational speed of at least one of feed package 250, rewind package 252, or godet roll 258 to maintain the tension in unwound yarns 109 within a threshold tension range that limits breakage and maintains entanglement, as described above. [00136] In embodiments where more than one yarn is rewound from a single feed package 250 onto at least two separate rewind packages 252, tension controller 264 controls operation of feed package 250, rewind package 252, and/or godet roll 258 to maintain the tensions of the separate yarns within 50 percent, 40 percent, 30 percent, 20 percent, 10 percent, 5 percent, or 1 percent of one another. Additional rewinding process parameters (e.g., finish application and/or entanglement) are also controlled to provide consistent properties in the separate yarns. Thus, example properties, such as yarn elongation, yarn tenacity, entanglement node density, and finish level, are maintained consistent in the separate yarns. [00137] Although not limited to the unwinding processes described herein, yarn 109 is generally unwound from feed package 250 by either “side”
withdrawal or “over-end” withdrawal. These methods of withdrawal differ from one another by how the core is oriented relative to a direction of yarn withdrawal from the feed package. As used herein, “side” refers to a withdrawal method in which the longitudinal axis of the core (e.g., longitudinal axis 174 as shown in FIGS.3, 4, 6, 8, and 10) is oriented perpendicularly relative to the direction of yarn withdrawal from the feed package, and the core rotates about its longitudinal axis during the yarn withdrawal. Thus, side withdrawal enables the yarns to be unwound from the core simultaneously and individually, as will be described in more detail below. As used herein, “over-end” refers to a withdrawal method in which the longitudinal axis of the core (e.g., longitudinal axis 174) is oriented generally parallel with the direction of yarn withdrawal from the feed package. The core may either be rotatable or rotatably stationary during the yarn withdrawal. Thus, over-end withdrawal enables the yarns to be unwound from the core individually or sequentially, as will be described in more detail below. [00138] The withdrawal method used to unwind yarns from feed package 250 may be selected based on a desire to twist the yarns while being unwound. For example, no additional twisting is added to the yarns when unwound by side withdrawal. As illustrated in FIGS. 15 and 16, system 248 includes a feed package 266 oriented for side withdrawal. Feed package 266 is formed from at least two individually-entangled yarns wound around at least one core 120 (e.g., a common core). In some embodiments, the at least one core 120 is mountable on a common unwinding shaft 268, which is rotatable to enable the yarns to be unwound from feed package 266 simultaneously and individually. [00139] Referring specifically to FIGS.15 and 16, the yarns of feed package 266 are co-wound in a combined or sectional configuration, similar to yarn package 162 illustrated in FIG.8. Because the combined yarns are capable of being individually unwound from core 120, at least two single yarn packages may be produced by rewinding the unwound yarns. For example, in some embodiments, a first yarn 270 and a second yarn 272, co-wound on core 120 in a combined configuration, are separated from one another as the combined yarn is unwound from feed package 266. In the example embodiment, first yarn
270 is unwound from feed package 266 to produce a first single-yarn rewind package 274, and second yarn 272 is unwound from feed package 266 to produce a second single-yarn rewind package 276. [00140] At least some known yarn rewinding systems include multiple feed packages and multiple rewind packages arranged in a one-to-one ratio such that yarn from each feed package is routed to a single associated rewind package. Accordingly, many known yarn rewinding systems arrange the feed packages and the rewind packages in pairs, with the rewind package positioned vertically above its associated feed package, for example. In some embodiments, these existing yarn rewinding systems may be modified (i.e., retrofitted) to produce at least two single-yarn packages from a multi-yarn feed package, as described herein. [00141] For example, referring to FIG.15, first yarn 270 and second yarn 272 are routed from feed package 266 to the separate cores 254 of each rewind package 274 and 276 along unequal length yarn paths. That is, first yarn 270 is routed directly from core 120 of feed package 266 to first rewind package 274, and second yarn 272 is routed indirectly from core 120 of feed package 266 to second rewind package 276, with yarn path of first yarn 270 being shorter than the yarn path of second yarn 272. In one embodiment, an existing yarn rewinding system may be modified to achieve this design. [00142] Specifically, feed package 266, first rewind package 274, and second rewind package 276 may positioned at the illustrated predefined locations on an existing rewinding system. Feed package 266 and first rewind package 274 may define a feed package-rewind package pair, as described above. Second rewind package 276 is positioned adjacent to first rewind package 274 in the predefined rewind location typically associated with a different feed package- rewind package pair. However, in the example embodiment, second rewind package 276 receives second yarn 272 from feed package 266 rather than from a separate feed package. System 248 includes at least one yarn guide 256 positioned between feed package 266 and second rewind package 276. Second yarn 272 is routed through yarn guide 256 before being rewound.
Accordingly, at least two single-yarn packages 274 and 276 may be produced using existing rewinding equipment. [00143] In the example embodiment, the tension in yarns 270 and 272 may be individually based on the length of yarn travel from feed package 266 to rewind packages 274 and 276. As illustrated in FIG.15, yarns 270 and 272 are routed to rewind packages 274 and 276 along unequal length yarn paths. Thus, the tension in yarns 270 and 272 may also be unequal. Differences in tension in yarns 270 and 272 may also be based on a wrap angle or a cumulative contact length of the yarns. The wrap angle of a yarn is defined by a total change in the direction of yarn withdrawal (e.g., in degrees) when the yarn contacts a rounded surface, such as when the second yarn 272 contacts yarn guide 256. The cumulative contact length is defined by a total length of contact between the yarn and the rounded surface This contact creates friction and impacts the tension applied on the yarn. Accordingly, one or both of yarns 270 and 272 may have a tension controller 264 associated therewith to facilitate equalizing the tension therebetween. [00144] Referring now to FIG.16, yarns 270 and 272 are routed indirectly from feed package 266 to rewind packages 274 and 276 along equal length yarn paths. Specifically, yarns 278 are unwound from feed package 266 and routed towards yarn guide 256. Yarns 278 are then separated prior to or at the at least one yarn guide 256 into its individually-entangled yarns 270 and 272, which are then routed to their respective rewind packages 274 and 276. Yarn guide 256 is positioned approximately equidistant from rewind packages 274 and 276. Thus, the tension in yarns 270 and 272 may inherently be approximately equal based on at least one of the equal length yarn paths, and/or the equal cumulative wrap angles or the equal cumulative contact lengths defined by contact between yarns 270 and 272 against yarn guide 256. [00145] As described above, the withdrawal method used to unwind yarns from feed package 250 may be selected based on a desire to twist the yarns while being unwound. For example, the yarns are twisted when unwound by over-end withdrawal. As illustrated in FIGS.17-19, system 248 includes a feed package 280 oriented for over-end withdrawal. Feed package 280 is formed
from at least two individually-entangled yarns wound around at least one core 120 (e.g., a common core) in a sectioned configuration. In some embodiments, the at least one core 120 is mountable on common unwinding shaft 268, which is operable to enable the yarns to be unwound from feed package 280 individually and sequentially, or simultaneously. [00146] In embodiments, where the yarns are capable of being individually and sequentially unwound from the at least one core 120, one or more single yarn packages may be produced by rewinding the unwound yarns. For example, referring to FIG.17, a first yarn 282 that defines a first yarn section 284 on core 120 may be unwound from feed package 280 to produce a first single-yarn rewind package 286. Once first yarn 282 is completely unwound from feed package 280, a second yarn 288 that defines a second yarn section 290 on core 120 may be unwound from feed package 280 to produce a second single-yarn rewind package 292. [00147] Referring now to FIG. 18, system 248 includes feed package 280 oriented for over-end withdrawal. In addition, at least one additional individually- entangled yarn may be spliced to first yarn 282. The splicing may occur at any point when a desired splicing location on first yarn 282 is accessible, and/or when splicing the additional yarn at the desired splicing location would not interfere in any additional unwinding of first yarn 282 from feed package 280. [00148] In the example embodiment, the full length of first yarn 282 is unwound from core 120, and second yarn 288 is spliced onto first yarn 282 at a splicing location 294. Both first yarn 282 and second yarn 288 may then be rewound onto the same core 254 to produce a rewind package 292. Alternatively, less than the full length of first yarn 282 may be unwound from core 120 prior to splicing. Further, any number of additional yarns may be spliced to increase the size of rewind package 292. [00149] In some end-use articles made of rewound yarns 109, splicing locations 294 may be visible on the final article. In woven articles, for example, splicing locations 294 located at the same point in the article may cause a visual defect in the article. Accordingly, when system 248 produces multiple rewind packages 292 from multiple feed packages 280, splicing locations 294 on the
different rewind packages 292 are different from one another to reduce the likelihood of forming a visual defect in a subsequently-formed article. This may be accomplished by, for example, varying the size of feed package 280 during yarn winding and production thereof, and/or by varying the size of rewind packages 286 and 292 during yarn unwinding and production thereof, such as by controlling the doffing time of the packages 280, 286, and 292. [00150] Referring now to FIG. 19, system 248 includes feed package 280 oriented for over-end withdrawal. In the example embodiment, yarns 282 and 288 are unwound from feed package 280 simultaneously. In addition, as a result of the over-end withdrawal, yarns 282 and 288 are twisted with one another as they are unwound to produce a twisted yarn 296. Twisted yarn 296 is rewound on core 254 to produce a rewind package 298. [00151] While FIGS. 17-19 are described in the context of feed packages having two yarn sections formed thereon, it should be understood that the embodiments illustrated therein may also be applicable to feed packages having more than two yarn sections formed thereon (e.g., packages 150 or 155). [00152] Referring now to FIG.20, a tow production facility 300 is illustrated therein. Tow production facility 300 includes a dope forming system 302, a spinning system 304, a cabinet 306, a tow band forming system 308, a tow band crimping system 310, and a tow band baling system 312. Tow production facility 300 may be used in the production of a cellulose acetate tow band, as described herein. [00153] For example, in the illustrated embodiment, dope forming system 302 mixes cellulose acetate flake in a solvent to produce a cellulose acetate dope 314, similar to the dope produced in yarn production system 100 in Figure 1. Dope 314 produced in dope forming system 302 may be channeled to spinning system 304, which includes at least one spinneret 316 (shown FIGS.21 and 22). Dope 314 discharged from spinneret 316 forms continuous cellulose acetate fibers or filaments 318, which are discharged into cabinet 306 to recover solvent therefrom. Filaments 318 may then be processed at systems 308, 310, and 312 to produce a tow band 320.
[00154] As the demand for cellulose acetate tow and yarn changes over time, various cellulose acetate production assets may become underutilized and/or dormant. For example, existing tow production assets may become underutilized as the demand for cellulose acetate tow decreases. Accordingly, in the embodiment illustrated in FIG.20, the existing tow production facility 300 is converted (i.e., retrofitted) to produce cellulose acetate yarn, and to process the produced yarns to produce packages of cellulosic yarn, as described above. [00155] In one embodiment or in combination with any embodiment mentioned herein, tow production facility 300 may be converted to a yarn production facility 322. This conversion may include utilizing at least some existing systems of tow production facility 300, installing new systems for use with at least some existing systems of tow production facility 300, and/or not utilizing at least one system of tow production facility 300. In the illustrated embodiment, dope forming system 302, spinning system 304, and/or cabinet 306 of tow production facility 300 may be utilized in the production of cellulose acetate yarn. [00156] In some embodiments, at least one of tow band forming system 308, tow band crimping system 310, or tow band baling system 312 is not utilized in the production of the cellulose acetate yarn. Accordingly, as illustrated, filaments 318 channeled through cabinet 306 are routed towards the newly installed systems for processing thereby, rather than to systems 308, 310, and 312. [00157] The newly installed systems facilitate the production of packages of cellulose acetate yarn. For example, in some embodiments, as shown in FIGS. 20-22, the newly installed systems include one or more systems of yarn production system 322, such as finish applicators 106, entanglement nozzles 108, yarn guides 110, and/or winders 112 installed downstream of spinning system 304. In addition, the newly installed systems may also include one or more separators 328 capable of separating tow band filaments into two or more groups of filaments, each group corresponding to its own distinct yarn. The filaments may be entangled to produce the yarns, and then wound onto cores or tubes to produce packages 329 of yarn, which are removable from winders
112. In such embodiments, winders 112 are spaced less than 20 feet, less than 10 feet, less than 5 feet, or less than 3 feet from the location from the location of entanglement (i.e., the location of entanglement nozzles 108 near the bottom of cabinet 306). [00158] Additionally, in some embodiments, yarns may be routed towards one or more additional winders when the capacity of winders 112 near the bottom of cabinet 306 has been reached, such as due to space constraints and the increased spinning capacity of the tow assets. Accordingly, in the illustrated embodiment, yarn production facility 322 may include one or more remote winders 330 located a distance from the existing yarn production assets. For example, remote winders 330 may be at least 10 feet, at least 20 feet, at least 30 feet, at least 40 feet, at least 50 feet, between 10 and 50 feet, between 20 and 40 feet, or between 20 and 30 feet from the location of cabinet 306. [00159] In some embodiments, conversion of tow production facility 300 to yarn production facility 322 may also include modifying spinning system 304 in a manner that facilitates production of yarns rather than a tow band. For example, spinnerets of tow production facility 300 may be single-cluster spinnerets that produce a single grouping of filaments. In some embodiments described herein, one or more spinnerets 316 (shown in FIGS.21 and 22) of tow production facility 300 may be either replaced or modified to have a plurality of groups of openings for producing a plurality of groups of filaments. In one embodiment, the groups filaments formed therefrom may be individually entangled and wound to produce packages 329, as described above. The group of filaments produced from the grouped section of openings may be separated and then wound at remote winders 330, as will be described in more detail below. [00160] Spinnerets 316 described herein may have at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, or at least 10 groups of openings for forming the distinct groups of filaments. [00161] Referring now to FIGS. 20, 21, and 22, dope forming system 302 includes at least one dope mixer 332, solvent recovery system 326, and dope pump 324. In the example embodiments, dope mixer 332 receives fresh solvent
334 and/or recovered solvent 336 from solvent recovery system 326. Dope mixer 332 may also receive solids 338, such as the cellulose acetate flake described above, for mixing with the solvents 334 or 336 to produce cellulose acetate dope 314. Dope 314 is then provided to at least one spinneret 316 in spinning system 304 to produce cellulose acetate filaments 318 therefrom. In some embodiments, spinnerets 316 spin dope 314 at a rate of greater than 500, greater than 600, greater than 700, greater than 800, or greater than 1000 meters per minute when forming filaments 318. [00162] In one embodiment or in combination with any embodiments mentioned herein, spinning system 304 spins filaments 318 into cabinet 306 at greater than 300, greater than 500, greater than 750, greater than 1000, greater than 1250, greater than 1500, between 300 and 2000, between 300 and 1500, between 500 and 1500, between 750 and 1500, between 1000 and 1500, or between 1250 and 1500 denier per cabinet. [00163] In one embodiment, filaments 318 are routed to finish applicators 106 and then entanglement nozzles 108 to produce individually-entangled yarns 334, as described above. Some yarns 334 are routed from a godet roll 342 to winders 112 near the bottom of the respective cabinet 306, as described above. In addition, yarn production facility 322 may include increase yarn winding capacity to accommodate the increased output of the initial tow production asset. Accordingly, additional yarns 334 may be routed from godet roll 342 to remote winders 330 to produce additional packages 329 therefrom. [00164] In the illustrated embodiment, filaments 318 are separated into groups of filaments having a reduced denier than the total output of spinning system 306. For example, filaments 318 may be spun into a plurality of cabinets 306, and filaments 318 discharged from each cabinet 306 may be routed to at least one separator 328 for separating filaments 318 into the plurality of groups. A separator 328 can be any that is known in the art capable of separating filaments 318 into the plurality of groups. An example of a separator includes a mechanical separator. [00165] In one embodiment or in combination with any embodiment mentioned herein, separators 328 are operable to separate filaments 318 into
groups each having a substantially equal denier. For example, filaments 318 may be separated into groups each having a denier between 20 and 300, between 30 and 200, between 40 and 150, or between 50 and 100. [00166] Filaments 318 routed to remote winders 330 may be separated and entangled prior to being routed the remote distance, or may be routed to remote winders 330 and then separated and entangled. For example, in one embodiment, separators 328 are positioned near the bottom of cabinet 306 to separate filaments 318 prior to routing to remote winders 330. In such embodiments, the separated and/or entangled groups of filaments 318 are routed to remote winders 330 through a plurality of separation channels 344, as illustrated in FIG.23. Separation channels 344 are sized to receive a single group of filaments 318 such that, when routed therethrough, filament crossing between the groups of filaments is limited or eliminated during the routing to remote winders 330. In some embodiments, filaments 318 may be further entangled at remote winders 330. [00167] Alternatively, filaments 318 may have a finish applied thereto and then be routed, without separation, the remote distance to remote winders 330. Filaments 318 may then be separated by separator 328, individually-entangled by entanglement nozzles 108, and wound to produce packages 329 at remote winders 330. [00168] Referring now to FIG. 22, filaments 318 are spun into a plurality of cabinets 306 and then combined to produce a band 320 of filaments with band forming system 308, for example. The band of filaments may then be separated by separators 328 into a plurality of groups of filaments, entangled, and wound. In one embodiment, the band may be conveyed to the remote winders in a single conveyor channel prior to separation and entanglement, thus eliminating the need for separate yarn channels to prevent filaments from crossing between groups. As described above, separators 328 are operable to separate filaments 318 into groups each having a substantially equal denier. For example, the filaments of band 320 may be separated into groups each having a denier between 20 and 300, between 30 and 200, between 40 and 150, or between 50 and 100. In some embodiments, the groups each include no greater than
300, no greater than 1000, no greater than 5000, or no greater than 10,000 cellulosic filaments. These groups of filaments may then be wound at remote winders 330 to produce packages 329. [00169] Additional advantages of the various embodiments will be apparent to those skilled in the art upon review of the disclosure herein. It will be appreciated that the various embodiments described herein are not necessarily mutually exclusive unless otherwise indicated herein. For example, a feature described or depicted in one embodiment may also be included in other embodiments but is not necessarily included. Thus, the present disclosure encompasses a variety of combinations and/or integrations of the specific embodiments described herein. DEFINITIONS [00170] As used herein, the terms “comprising,” “comprises,” and “comprise” are open-ended transition terms used to transition from a subject recited before the term to one or more elements recited after the term, where the element or elements listed after the transition term are not necessarily the only elements that make up the subject. [00171] As used herein, the terms “including,” “includes,” and “include” have the same open-ended meaning as “comprising,” “comprises,” and “comprise.” [00172] As used herein, the terms “having,” “has,” and “have” have the same open-ended meaning as “comprising,” “comprises,” and “comprise.” [00173] As used herein, the terms “containing,” “contains,” and “contain” have the same open-ended meaning as “comprising,” “comprises,” and “comprise.” [00174] As used herein, the terms “a,” “an,” “the,” and “said” mean one or more. [00175] As used herein, the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
[00176] The preferred forms of the invention described above are to be used as illustration only, and should not be used in a limiting sense to interpret the scope of the present invention. Obvious modifications to the exemplary embodiments, set forth above, could be readily made by those skilled in the art without departing from the spirit of the present invention. [00177] The inventors hereby state their intent to rely on the Equivalents to determine and assess the reasonably fair scope of the present invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set forth in the following claims. NUMERICAL RANGES [00178] The present description uses numerical ranges to quantify certain parameters relating to the invention. It should be understood that when numerical ranges are provided, such ranges are to be construed as providing literal support for claim limitations that only recite the lower value of the range as well as claim limitations that only recite the upper value of the range. For example, a disclosed numerical range of 10 to 100 provides literal support for a claim reciting “greater than 10” (with no upper bounds) and a claim reciting “less than 100” (with no lower bounds). [00179] Additionally, it should be understood that a listing of numerical values following a descriptor, such as “at least” and “not more than,” provides literal support for a range based on all of the numerical values following that descriptor. For example, a statement specifying “at least 2, 5, or 10 and/or not more than 100, 50, or 25” would provide literal support for ranges of “at least 25,” “not more than 50,” and “at least 10 and not more than 25.” EXAMPLES [00180] In the conventional process of extruding filaments and making yarn packages, each group of yarn is extruded from one spinneret, passes through the cabinet, then is threaded through a set of auxiliary devices before being wound onto separate cores to form a package on the winder. To increase yarn production capacity, multiple groups of openings? can be incorporated into one
spinneret, enabling the extrusion of multiple groups of filaments or yarns from a single spinneret. Without increasing the number of existing winders, multiple yarn groups can be wound onto one core using different methods. Example One to Four describe the production processes, respectively, of making conventional packages, conventional packages with increased capacity, combined packages with increased capacity, and sectional packages with increased capacity, using two spinnerets in one cabinet as the basic unit. Example One [00181] A first yarn was produced from the 1st spinneret in one cabinet, and a second yarn was produced from the 2nd spinneret in the same cabinet. The two yarns were kept separate in the cabinet through two yarn guides at the exit. After exiting the cabinet, two yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before being wound onto separate cores on a common winder spool. The throughput of this conventional set up establishes the baseline capacity. Example Two [00182] A first and a second yarn were produced from the 1st spinneret in one cabinet, and a third and fourth yarn were produced from the 2nd spinneret in the same cabinet. The four yarns were kept separate in the cabinet through four yarn guides at the exit. After exiting the cabinet, the yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before wounding onto cores. The first and second yarns were wound separately onto two cores on a common spool on the first winder. Similarly, the third and fourth yarns were wound by using a second winder. Compared to the conventional process, this example doubled the throughput of one cabinet while maintaining the same output per winder. Example Three [00183] A first and a second yarn were produced from the 1st spinneret in one cabinet, and a third and fourth yarn were produced from the 2nd spinneret in the
same cabinet. The four groups of yarns were kept separate in the cabinet through four yarn guides at the exit. After exiting the cabinet, the yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before winding. The first and second yarns were then combined and threaded through a first yarn guide, co-wound on the same section of the first core on a winder spool. Similarly, the third and fourth yarns were co-wound on the same section of the second core on the same winder spool using a second yarn guide. Compared to the conventional process, this example doubled the throughput for both the cabinet and the winder. Example Four [00184] A first and a second yarn were produced from the 1st spinneret in one cabinet, and a third and fourth yarn were produced from the 2nd spinneret in the same cabinet. The four groups of yarns were kept separate in the cabinet through four yarn guides at the exit. After exiting the cabinet, the yarns were individually lubricated before taken up by a shared godet roll. Then each yarn was entangled before winding The first yarn was wounded on the first section of the first core on a winder spool, and the second yarn was co-wound on the second section of the same core. The third and fourth yarns were co-wound in the same manner on two sections of the second core on the same winder spool. Compared to the conventional process, this example doubled the throughput for both the cabinet and the winder. [00185] Table 1 summarizes the production setups, throughputs, and yarn package parameters of Example One to Four. All the examples were based on the same production conditions including the dope solids, dope temperature, draw ratio, and spinning speed in the ranges described in this disclosure. The yarn specifications were 75 denier/19 filaments, 2.0% FOY, 1.3 gpd tenacity, 21% elongation, and 11 entanglement nodes per foot. The package dimensions were measured using a ruler, and the package weight was obtained by weighing the package on a calibrated scale and subtracting the core weight. The helix angle was calculated from the known the winder speeds in the traverse and spool rotating directions. Examples 2-4 doubled the throughput
compared to Example One due to the increase in the number of groups resulting from the change from conventional spinnerets to spinnerets with multiple hole groupings. Example 3 and Example 4 doubled the number of yarns per winder compared to Example One and Two by winding multiple yarns per core. In Example 4, due to the sectional structure of the package, there is a small gap between sections defined as the section-to-section distance. As a result, the package weight in Example 4 is lower, and the helix angle is set higher to ensure package stability. TABLE 1 Comparison of Cellulose Acetate Yarn Production Setups, Throughputs, and Yarn Package Parameters Example Example Example One Example Two Three Example Four
Settings Conventional Combined Sectional (One Cabinet) Package with Package with Package with Conventional Increased Increased Increased Package Capacity Capacity Capacity Number of Spinnerets 2 2 2 2 Number of Clusters/Spinneret 1
2 Number of Yarn Groups 2 4 4 4 Number of Lube Applicators 2 4 4 4 Number of TF Applicators 2
Number of Tension Guides 2 4 4 4 Number of Winders 1 2 1 1 Number of Cores/Winder 2 2 2 2 Number of Sections/Core 1 1 1 2 Number of Yarns/Section 1 1
1 Number of Yarns/Winder 2 2 4 4
Comparison of Cellulose Acetate Yarn Production Setups, Throughputs, and Yarn Package Parameters Example Example Example One Example Two Three Example Four
Settings Conventional Combined Sectional (One Cabinet) Package with Package with Package with Conventional Increased Increased Increased Package Capacity Capacity Capacity Throughput (kg/hr) 0.74 1.47 1.47 1.47 Core Length (cm) 17.4 17.4 17.4 17.4 Section Length (cm) 14.6 14.6 14.6 6.7 Section to Section Distance (mm) -- -- -- 1.6 Helix Angle (˚) 9.0 9.0 9.0 9.2 Package Weight (not including core) (kg)
Claims
WHAT IS CLAIMED IS: 1. A method of producing acetate yarn, the method comprising: providing an acetate tow production facility comprising a dope forming system, a spinning system, a tow band forming system, a tow band crimping system,and a tow band baling system; converting the acetate tow production facility into an acetate yarn production facility, wherein the converting comprises installing a yarn winder downstream of the spinning system; and producing packages of acetate yarn using the acetate yarn production facility, wherein the producing comprises: forming a cellulose acetate dope using the dope forming system; spinning cellulose acetate filaments from the cellulose acetate dope using the spinning system; and winding the cellulose acetate filaments using the yarn winder to produce the packages of acetate yarn, wherein at least one of the tow band forming system, the tow band crimping system, or the tow band baling system is not utilized during the producing step.
2. The method in accordance with Claim 1, wherein the converting further comprises installing at least one spinneret, having a plurality of groupings of openings for producing the cellulose acetate filaments, in the spinning system.
3. The method in accordance with Claim 1, wherein the spinning system spins the cellulose acetate filaments into a plurality of cabinets.
4. The method in accordance with Claim 1 further comprising: combining filaments from at least one cabinet to produce a band of filaments; and separating the band of filaments into a plurality of groups of filaments comprising no greater than 300.
5. The method in accordance with Claim 4, wherein the separating is carried out at one or both of (i) near the bottom of a cabinet of the acetate tow production facility and/or (ii) near a remote yarn winder spaced at least 20 feet from the bottom of the cabinet.
6. The method in accordance with Claim 1 further comprising individually entangling groups of the cellulose acetate filaments to produce a plurality of individually-entangled yarns.
7. The method in accordance with Claim 1, wherein the individually entangling is carried out at one or both of (i) near the bottom of a cabinet of the acetate tow production facility and/or (ii) near a remote yarn winder spaced at least 20 feet from the bottom of the cabinet.
8. The method in accordance with Claim 1 further comprising individually applying a finish to each of the groups of filaments prior to entanglement thereof.
9. The method in accordance with Claim 1, wherein the winding further comprises winding the individually-entangled yarns to produce the packages of acetate yarn, wherein the winding comprises at least one of: winding at least two individually-entangled yarns using the yarn winder; or routing at least one individually-entangled yarn to a remote yarn winder spaced at least 20 feet from the yarn winder; or routing the plurality of cellulose acetate filaments to the remote yarn winder prior to entanglement thereof.
10. The method in accordance with Claim 9, wherein the routing further comprises routing a plurality of individually-entangled yarns to the remote yarn winder through a plurality of separation channels, wherein one individually-
entangled yarn is routed through each separation channel to limit filament crossing during the routing.
11. The method in accordance with Claim 1, wherein the winding further comprises winding at least two individually-entangled yarns around different cores on a common spool.
12. The method in accordance with Claim 1, wherein the winding further comprises winding the at least two individually-entangled yarns around a common core on the common spool.
13. The method in accordance with Claim 12, wherein the winding further comprises co-winding the at least two individually-entangled yarns around the common core.
14. The method in accordance with Claim 12, wherein the winding further comprises co-winding the at least two individually-entangled yarns around at least one common section of the common core.
15. The method in accordance with Claim 12, wherein the winding further comprises winding the at least two individually-entangled yarns around separate sections of the common core.
16. The method in accordance with Claim 12, wherein the winding further comprises forming a first yarn section from a first yarn, and a second yarn section from a second yarn, on the common core, wherein the first and second yarn sections are spaced from one another on the common core.
17. The method in accordance with Claim 12, wherein the winding further comprises forming a first yarn section from a first yarn, and a second yarn section from a second yarn, on the common core, wherein the first and second
yarn sections are adjacent to and in substantial contact with one another on the common core.
18. The method in accordance with Claim 1 further comprising routing at least two individually-entangled yarns to a common spool from a common yarn guide.
19. The method in accordance with Claim 1 further comprising individually routing at least two individually-entangled yarns to a common spool from different yarn guides.
20. The method in accordance with Claim 1, wherein the spinning comprises spinning the plurality of cellulose acetate filaments from at least one spinneret having a plurality of groupings of openings for producing the cellulose acetate filaments.
21. The method in accordance with Claim 19, wherein the individually- entangling further comprises individually entangling the groups of filaments at one or both of near the bottom of a cabinet of the acetate tow production facility, or near a remote yarn winder spaced at least 20 feet from the bottom of the cabinet.
22. The method in accordance with Claim 1 further comprising individually applying a finish to each of the groups of filaments prior to entanglement thereof.
23. The method in accordance with Claim 1, wherein the winding further comprises winding the individually-entangled yarns to produce the packages of acetate yarn, wherein the winding comprises at least one of: winding at least two individually-entangled yarns using the yarn winder; or
routing at least one individually-entangled yarn to a remote yarn winder spaced at least 20 feet from the yarn winder; or routing the plurality of cellulose acetate filaments to the remote yarn winder prior to entanglement thereof.
24. The method in accordance with Claim 23, wherein the routing further comprises routing a plurality of individually-entangled yarns to the remote yarn winder through a plurality of separation channels, wherein one individually- entangled yarn is routed through each separation channel to limit filament crossing during the routing.
25. The method in accordance with Claim 1, wherein the winding further comprises winding at least two individually-entangled yarns around different cores on a common spool.
26. The method in accordance with Claim 1, wherein the winding further comprises winding the at least two individually-entangled yarns around a common core on the common spool.
27. The method in accordance with Claim 26, wherein the winding further comprises co-winding the at least two individually-entangled yarns around the common core.
28. The method in accordance with Claim 27, wherein the winding further comprises winding the at least two individually-entangled yarns around at least one common section of the common core.
29. The method in accordance with Claim 27, wherein the winding further comprises winding the at least two individually-entangled yarns around separate sections of the common core.
30. The method in accordance with Claim 27, wherein the winding further comprises forming a first yarn section from a first yarn, and a second yarn section from a second yarn, on the common core, wherein the first and second yarn sections are spaced from one another on the common core.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
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| US202363500055P | 2023-05-04 | 2023-05-04 | |
| US63/500,055 | 2023-05-04 |
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| WO2024229061A3 WO2024229061A3 (en) | 2025-01-16 |
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| PCT/US2024/027130 Pending WO2024229061A2 (en) | 2023-05-04 | 2024-05-01 | Methods of converting assets to increase cellulosic yarn production |
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| ITTO20020081A1 (en) * | 2002-01-29 | 2003-07-29 | Tecnofil Srl | APPARATUS AND METHOD FOR THE PRODUCTION OF YARN. |
| US7585442B2 (en) * | 2004-06-25 | 2009-09-08 | Celanese Acetate, Llc | Process for making cellulose acetate tow |
| US20080245276A1 (en) * | 2007-04-04 | 2008-10-09 | Massafacil Ind. Com. Argamassa, Ltda | Lining mortar |
| JP6415077B2 (en) * | 2014-04-01 | 2018-10-31 | 株式会社ダイセル | Hydrophilic cellulose acetate tow band and absorber using the same |
| JP7217099B2 (en) * | 2018-07-12 | 2023-02-02 | 株式会社ダイセル | Cellulose acetate fiber, cellulose acetate tow band, and method for producing cellulose acetate tow band |
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