EP2108719B1 - An apparatus, process and an array of nozzles for extruding cellulose fibers - Google Patents
An apparatus, process and an array of nozzles for extruding cellulose fibers Download PDFInfo
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- EP2108719B1 EP2108719B1 EP09005315A EP09005315A EP2108719B1 EP 2108719 B1 EP2108719 B1 EP 2108719B1 EP 09005315 A EP09005315 A EP 09005315A EP 09005315 A EP09005315 A EP 09005315A EP 2108719 B1 EP2108719 B1 EP 2108719B1
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- openings
- nozzles
- pressurized gas
- aqueous solution
- diameter
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- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
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- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
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- ORXJMBXYSGGCHG-UHFFFAOYSA-N dimethyl 2-methoxypropanedioate Chemical compound COC(=O)C(OC)C(=O)OC ORXJMBXYSGGCHG-UHFFFAOYSA-N 0.000 description 1
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Images
Classifications
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- 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
- D01D4/00—Spinnerette packs; Cleaning thereof
- D01D4/02—Spinnerettes
- D01D4/025—Melt-blowing or solution-blowing dies
-
- 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
- D01D5/12—Stretch-spinning methods
- D01D5/14—Stretch-spinning methods with flowing liquid or gaseous stretching media, e.g. solution-blowing
-
- 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
Definitions
- This invention relates to an apparatus, process and an array of nozzles for extruding cellulose fibers.
- the die block assembly can include various components for directing and distributing the aqueous solution and pressurized gas through a plurality of nozzles to form a plurality of molten filaments.
- the aqueous solution is usually extruded in a downward direction such that the pressurized gas and gravity will cause the aqueous solution to attenuate into a plurality of molten filaments.
- the molten filaments are then contacted with a liquid which causes a major portion of the solvent to solvate into the liquid solution and thus allows the molten filaments to coagulate into solid cellulose fibers.
- a moving surface such as a porous conveyor belt or rotatable drum and form a non-woven web.
- no one to date has been able to extrude and form very fine cellulose fibers having a diameter of less than 5 micron at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to about 750 meters per minute.
- no one to date has been able to form a non-woven web constructed from such cellulose fibers which has a basis weight of less than about 1 gram per square meter at a production rate of more than about 30 meters per minute.
- International application WO 2005/106085 A1 discloses a method and apparatus in which a cellulose solution is extruded through a first multiplicity of uniformly spaced apart nozzles and upon exiting the nozzles is accelerated and attenuated by high velocity gaseous jets to form fine cellulosic fibers.
- a coagulating solution is forced through a second multiplicity of nozzles uniformly spaced apart from each other and uniformly spaced apart from and generally parallel to the first multiplicity of nozzles and forming high velocity jets so that the coagulating solution impinges on the fine cellulosic fibers further attenuating them and causing them to coagulate.
- an apparatus according to claim 1, a process according to claim 5, and a use according to claim 11 have been invented which will allow one to extrude and form cellulose fibers each having a diameter of less than about 15 microns at a throughput of greater than about 0.1 grams/hote/minute.
- the apparatus, process and array of nozzles is also capable of forming very fine cellulose fibers each having a diameter of less than about 5 microns at a throughput of greater than about 0.5 grams/hole/minute.
- the apparatus, process and array of nozzles produces cellulose fibers having unique characteristics that can be collected to form a non-woven web.
- the apparatus includes a first member secured to a dope delivery mechanism.
- the first member has multiple nozzles arranged in rows.
- Each of the nozzles has an inside diameter through which an aqueous solution of cellulose and a solvent can be extruded.
- Each of the nozzles also has at least one other passage formed therein through which a pressurized gas can be routed.
- the apparatus also includes a second member secured to the first member.
- the second member has multiple corridors formed therethrough which are connected to the passage formed in the first member, and multiple openings formed therein through which the multiple nozzles can pass.
- the apparatus further includes a third member secured to the second member.
- the third member has multiple first openings formed therethrough. Each of the multiple first openings is sized to permit one of the multiple nozzles to pass therethrough. Each of the first openings being connected to the pressurized gas corridors formed in the second member. Each of the first openings is capable of emitting pressurized gas therethrough such that the pressurized gas at least partially surrounds the aqueous solution extruded from each of the nozzles.
- the third member also has multiple second openings formed therethrough which are connected to the pressurized gas corridors formed in the second member. Each of the second openings is positioned adjacent to one of the nozzles, in each of the rows, and each of the second openings has an opening through which the pressurized gas can be emitted.
- the process includes the steps of forming an aqueous solution of cellulose and a solvent.
- This aqueous solution is directed through a spinnerette having multiple rows of nozzles and second openings.
- the nozzles are different from the second openings.
- At least one of the nozzles in one of the rows is staggered from at least one of the nozzles in an adjacent row, and each of the nozzles having a first opening aligned adjacent thereto.
- the aqueous solution is extruded through each of the nozzles to form multiple molten filaments. At least a portion of each of the molten filaments is shrouded in a pressurized gas emitted through the adjacent first opening.
- the molten filaments are then attenuated into a circular cross-sectional configuration having a diameter of less than about 5 microns.
- Each of the molten filaments is contacted with a liquid which chemically reacts with the solvent to remove some of the solvent whereby each of the molten filaments is transformed into a continuous solid fiber.
- the continuous solid fibers are then collected on a moving surface to form a non-woven cellulose web.
- Each nozzle has a longitudinal central axis and includes a hollow cylindrical tube with a predetermined cross-section.
- An aqueous solution of cellulose and a solvent is extruded through each of the hollow cylindrical tubes into multiple individual molten filaments.
- Each of the hollow cylindrical tubes is surrounded by a first opening having a uniquely shaped cross-section with a diameter. The diameter of each of the first openings is greater than the diameter of each of the hollow cylindrical tubes.
- Each of the first openings is capable of emitting a pressurized gas which surrounds one of the extruded molten filaments.
- At least three second openings are spaced outward from each of the first openings.
- Each of the second openings is capable of emitting a pressurized gas stream essentially parallel to the longitudinal central axis of each of the nozzles which functions to shrouds each of the extruded molten filaments.
- the general object of this invention is to provide an apparatus capable of extruding cellulose fibers having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to about 750 meters per minute.
- a more specific object of this invention is to provide an apparatus capable of extruding very fine cellulose fibers having a diameter of less than about 5 microns at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to about 750 meters per minute.
- Another object of this invention is to provide an apparatus for extruding cellulose fibers having a circular cross-sectional configuration and a diameter of about 5 microns or less.
- a further object of this invention is to provide an apparatus for extruding very fine cellulose fibers having a diameter of less than about 3 microns.
- Still another object of this invention is to provide an apparatus for extruding cellulose fibers which includes an array of nozzles which are capable of extruding an aqueous solution of cellulose and a water soluble solvent along with pressurized gas such that an attenuated molten filament will not adhere to an adjacent molten filament.
- an object of this invention is to provide an apparatus for extruding cellulose fibers in an economical and efficient manner.
- Another object of this invention is to provide a process of forming a non-woven cellulose web.
- a more specific object of this invention is to provide a non-woven cellulose web produced by such a process.
- Still another object of this invention is to provide a process of forming a web from multiple cellulose fibers each having a diameter of less than about 15 microns.
- Still another object of this invention is to provide a use of an array of nozzles for extruding multiple cellulose fibers at high speeds.
- a more specific object of this invention is to provide a use of an array of nozzles for extruding multiple cellulose fibers having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to about 750 meters per minute..
- an object of this invention is to provide a use of an array of nozzles for extruding multiple cellulose fibers each having a uniquely shaped cross-sectional configuration and a diameter of about 5 microns or less.
- an apparatus for extruding cellulose fibers comprises: a) a first member having multiple nozzles arranged in rows, each of said nozzles having an inside diameter through which an aqueous solution comprised of cellulose and a solvent can be extruded, and having at least one passage formed therein through which a pressurized gas can be routed; b) a second member secured to said first member, said second member having multiple corridors formed therethrough which are connected to said at least one passage formed in said first member, and multiple openings formed therein through which said multiple nozzles can pass; and c) a third member secured to said second member, said third member having multiple first openings formed therethrough, each of said multiple first openings sized to permit one of said multiple nozzles to pass through, each of said multiple first openings being concentrically aligned about each of said multiple nozzles, each of said multiple first openings being connected to said pressurized gas corridors formed in said second member and each capable of emitting pressurized gas therethrough such that said
- the apparatus of one of the previous embodiments is capable of forming cellulose fibers having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute, and in particular capable of forming cellulose fibers having a diameter of less than about 5 microns at a throughput of greater than 0.5 grams/hole/minute.
- said third member has an even number of rows of nozzles with at least one of said nozzles in one row being offset from one of said nozzles in an adjacent row.
- each of said multiple hollow cylindrical tubes has an inside diameter ranging from between about 0.125 millimeters to about 01.25 millimeters.
- each of said multiple nozzles is formed from stainless steel.
- each of said multiple second openings has a venturi formed therein.
- said third member has an odd number of rows, and wherein at least two of said nozzles in one row are offset from two of said nozzles in an adjacent row.
- each of said second openings contains a pin therein.
- an apparatus for extruding cellulose fibers comprises: a) a filter block secured to a dope delivery mechanism, said filter block having a first passageway formed therein through which an aqueous solution comprised of cellulose and a solvent can be routed, and a second passageway formed therein through which a pressurized gas can be routed; b) a spinnerette secured to said filter block, said spinnerette having multiple nozzles arranged in rows, each of said nozzles having a longitudinal central axis with an inside diameter through which said aqueous solution can be extruded, and said spinnerette having at least one passage formed therethrough which is connected to said second passageway; c) a gas distribution plate secured to said spinnerette, said gas distribution plate having multiple corridors formed therethrough which are connected to said at least one passage formed in said spinnerette, and multiple openings formed therein through which said multiple nozzles can pass; and d) an exterior plate secured to said gas distribution
- said exterior plate has at least three rows of nozzles with each row containing an equal number or an unequal number of said first and second openings.
- said exterior plate has at least 20 openings per linear centimeter.
- an apparatus comprises: a) a dope delivery mechanism having a first conduit formed therein through which an aqueous solution comprised of cellulose and a solvent can be routed, and a second conduit formed therein through which a pressurized gas can be routed; b) a filter block secured to said dope delivery mechanism, said filter block having at least two separate passageways formed therethrough, each of said passageways connecting with one of first and second conduits; c) a spinnerette secured to said filter block, said spinnerette having multiple nozzles arranged in rows, each of said nozzles being an elongated, hollow tube having a longitudinal central axis with a cross-section having an opening through which said aqueous solution can be extruded and having at least one passage formed therein which is connected to said pressurized gas passageway formed in said filter block; d) a gas distribution plate secured to said spinnerette, said gas distribution plate having multiple corridors formed therein which are connected
- pressurized gas can pass through said assembly at a velocity of at least 45 meters per second and each of said multiple first openings includes at least two crescent shaped slots.
- said exterior plate has at least 60 openings per linear centimeter.
- an apparatus comprises an array of nozzles for extruding multiple cellulose fibers, comprising: a) multiple nozzles each having a longitudinal central axis and each including a tube with a cross-section having a diameter through which an aqueous solution comprised of cellulose and a solvent can be extruded into a molten filament, and a first opening surrounding each of said tubes having a cross-section with a diameter, said diameter of said first opening being greater than said diameter of said tube, and each of said first openings capable of emitting a pressurized gas which surrounds one of said extruded molten filaments; and b) at least three second openings each spaced outward from each of said first openings, each of said second openings capable of emitting a pressurized gas stream essentially parallel to said longitudinal central axis of said nozzle, and each of said pressurized gas streams functioning to shroud one of said extruded molten filaments.
- said pressurized gas emitted from each of said first openings attenuates and accelerates each of said molten filaments extruded from each of said tubes into a continuous fiber having a diameter of less than about 15 microns.
- each of said first and second openings is aligned parallel to one another.
- each of said second openings is spaced from between about 1 millimeter to about 4 millimeters from said longitudinal central axis of said nozzle, and each of said second openings is spaced from between about 1 millimeter to about 2 millimeters from said longitudinal central axis of one of said nozzles.
- each of said tubes extends downward beyond said first openings by at least 1 millimeter, in particular by at least 3. millimeters, and in particular by at least 5 millimeters.
- an apparatus comprises an array of nozzles comprising: a) multiple nozzles each having a longitudinal central axis and each including a hollow cylindrical tube with a cross-section having a constant diameter through which an aqueous solution comprised of cellulose and a water soluble solvent can be extruded into a molten filament, and a first opening surrounding each of said hollow cylindrical tubes and having a cross-section with a constant diameter, said diameter of each of said first openings being greater than said diameter of each of said hollow cylindrical tubes, and each of said first openings capable of emitting a pressurized gas which at least partially surrounds one of said extruded molten filaments; and b) a plurality of second openings each spaced outward from each of said first openings, each of said second openings capable of emitting a pressurized gas stream essentially parallel to said longitudinal central axis of each of said nozzles, and each of said pressurized gas streams functioning to shrou
- each first opening there are at least three second openings for each first opening and each of said second openings is equally spaced apart from an adjacent second opening.
- each first opening there are eight second openings for each first opening and each of said second openings is spaced approximately 45 degrees apart.
- an apparatus comprises an array of nozzles comprising: a) multiple nozzles arranged in rows, each of said nozzle having a longitudinal central axis and including a hollow cylindrical tube with a cross-section and having a constant diameter positioned therein through which an aqueous solution comprised of cellulose and a water soluble solvent can be extruded into a molten filament, and a first opening concentrically aligned about each of said hollow cylindrical tubes and having a cross-section with a constant diameter, said diameter of said first opening being greater than said diameter of each of said hollow cylindrical tubes, and said first opening capable of emitting pressurized gas therethrough which at least partially surrounds said extruded molten filament; b) multiple second openings arranged in said rows with said multiple nozzles, at least two of said second openings being positioned adjacent to one of said nozzles in each of said rows, each of said second openings having a pin positioned therein and having a diameter
- each of said first openings includes at least two crescent shaped slots spaced apart from said hollow cylindrical tube.
- each of said hollow cylindrical tubes is vertically spaced downward from each of said first openings by at least 3 millimeters.
- each of said second openings has a sidewall aligned perpendicular to each of said second openings.
- an process of forming a non-woven cellulose web comprises: a) forming an aqueous solution of cellulose and a solvent; b) directing said aqueous solution through a first member having multiple rows of first and second openings, each of said first openings having a nozzle positioned therein, and at least one of said nozzles in a row being staggered from at least one of said nozzles in an adjacent row; c) extruding said aqueous solution through each of said nozzles to form multiple molten filaments; d) shrouding at least a portion of each of said molten filaments in a pressurized gas emitted through each of said adjacently aligned first and second openings; e) attenuating said molten filaments into a circular cross-sectional configuration having a diameter of less than about 15 microns; f) contacting said molten filaments with a liquid, said liquid mixing with said solvent to remove some of said solvent whereby each of
- the process of one of the previous embodiments comprises heating said aqueous solution to a temperature of from between about 80°C to about 140°C and heating said pressurized gas to a temperature of at least about 120 °C.
- the process of one of the previous embodiments comprises extruding said aqueous solution through each of said nozzles at a throughput of greater than 0.1 grams/hole/minute.
- the process of one of the previous embodiments comprises emitting said pressurized gas through each of said first openings at a velocity of at least 45 meters per second and each of said first openings includes at least two crescent shaped slots.
- the process of one of the previous embodiments comprises emitting said pressurized gas through each of said second openings at a velocity of at least 45 meters per second.
- said pressurized gas is pressurized air which is emitted from each of said first openings essentially parallel to said molten filament extruded through each of said nozzles, and said pressurized air accelerates and attenuates each of said molten filaments.
- the process of one of the previous embodiments comprises contacting each of said molten filaments with a liquid which causes said molten filaments to coagulate into a continuous solid fiber.
- said liquid is water
- each of said molten filaments is contacted with said water at a distance of at least about 3 centimeters from each of said nozzle.
- the process of one of the previous embodiments comprises: a) forming an aqueous solution of cellulose and a solvent, said aqueous solution having a temperature of at least about 100 °C; b) directing said aqueous solution through a first member having multiple rows of first and second openings, each of said first openings having a nozzle positioned therein, and at least one of said nozzles in a row being staggered from at least one of said nozzles in an adjacent row, c) extruding said aqueous solution through each of said nozzles at a back pressure of at least 10 bar to form multiple molten filaments; d) shrouding at least a portion of each of said molten filaments in a pressurized gas emitted through each of said adjacently aligned first and second openings; e) attenuating said molten filaments into a circular cross-sectional configuration having a diameter of less than about 5 microns; f) contacting said molten filaments into
- said pressurized gas emitted from each of said second openings prevents each of said molten filaments from physically contacting one another.
- the process of one of the previous embodiments comprises extruding said aqueous solution downward from each of said nozzles parallel to a longitudinal central axis and contacting each of said molten filaments with water introduced at an angle of from between about 5 degrees to about 175 degrees, said water causing each of said molten filaments to coagulate into a continuous solid fiber.
- the process of one of the previous embodiments comprises heating said pressurized gas to a temperature from between about 120° C to about 160° C.
- said moving surface is a rotatable drum having a porous surface or a conveyor belt having a porous surface.
- the process of one of the previous embodiments comprises starting up said process by: a) heating said aqueous solution to a predetermined temperature above 80° C; b) directing said heated aqueous solution to said first member and extruding said heated aqueous solution through each of said nozzles at a back pressure of at least 10 bar, c) routing said pressurized gas through each of said first and second openings at a velocity of from between about 1 meter per second to about 10 meters per second; d) heating said pressurized gas to a temperature of about 100° C; and e) gradually increasing said velocity of said heated pressurized gas until said pressurized gas reaches a velocity of at least about 45 meters per second.
- the process of one of the previous embodiments comprises shutting down said process by: a) turning off said heat used to heat said pressurized gas; b) gradually reducing said velocity of said pressurized gas to 0 meters per second; c) stopping said aqueous solution from flowing through each of said nozzles; and d) allowing said aqueous solution to cool to room temperature.
- a process 10 of forming cellulose fibers 12 which can be formed into a non-woven web 14 is shown.
- the process 10 includes the steps of combining and dissolving cellulose 16 and a solvent 18 to form an aqueous solution 20.
- the aqueous solution 20 is commonly referred to as dope in the industry.
- the type of raw cellulosic material used can vary.
- Cellulose is a complex carbohydrate C 6 H 10 O 5 that is composed of glucose units which form the main constituent of the cell wall in most plants.
- the cellulosic material may be bleached or unbleached wood pulp which can be made by various processes of which kraft, pre-hydrolyzed kraft, and sulfite would be exemplary.
- the cellulose 16 can be wood pulp from any of a number of commercially available dissolving or non-dissolving grade pulps. Examples of some sources of wood pulp include: The Weyerhaeuser Company, International Paper Company, Sappi Saiccor sulfite pulp, and pre-hydrolyzed kraft pulp from International Paper Company. In addition, the wood pulp can be a high hemi-cellulose with a low degree of polymerization pulp.
- the cellulosic material can be chopped or shredded into a fine fluff to promote forming an aqueous solution 20 with the solvent 18.
- the solvent 18 is desirably a water soluble solvent.
- the solvent 18 can be an amine oxide, desirably a tertiary amine N-oxide containing a non-solvent for the cellulose, such as water.
- Representative examples of amine oxide solvents useful in the practice of this invention are set forth in U.S. Patent 5,409,532, issued to Astegger et al .
- the desired solvent is N-methyl-morpholine-N-oxide (NMMO).
- NMMO N-methyl-morpholine-N-oxide
- Other representative examples of solvents include dimethylsulfoxide (DMSO), dimethylacetamide (DMAC), dimethylforamide (DMF) and caprolactan derivatives.
- DMSO dimethylsulfoxide
- DMAC dimethylacetamide
- DMF dimethylforamide
- caprolactan derivatives caprolactan derivatives.
- the pulp can be dissolved in an amine oxide solvent by any art recognized means such as set forth in
- Still other solvents that may be used in this invention include dilute caustic soda, phosphoric acid, a mixture of liquid ammonia/ammonia thiocynate and others.
- Still another way of making an aqueous solution of the cellulose is described in U.S. Patent 6,306,334 issued to Luo et al .
- the aqueous solution 20 is then heated in a heater 22 or by some other type of heating mechanism to a predetermined elevated temperature.
- the aqueous solution 20 can be heated to a temperature ranging from between about 80° C to about 140° C. Desirably, the aqueous solution 20 is heated to a temperature of at least 100° C. More desirably, the aqueous solution 20 is heated to a temperature of at least about 110° C. Most desirably, the aqueous solution 20 is heated to a temperature of at least about 120° C.
- the aqueous solution 20 of the cellulose 16 and solvent 18 can be made in a known manner, for example, as taught in U.S. Patent 4,246,221, issued to McCorsley, III which is incorporated by reference and made a part hereof.
- U.S. Patent 4,246,221 the cellulose is wet in a non-solvent mixture of about 40% NMMO and 60% water.
- the ratio of cellulose to wet NMMO is about 1:5.1 by weight.
- the mixture is mixed in a double arm sigma blade mixer for about 1.3 hours under vacuum at about 120° C until sufficient water has been distilled off to leave about 12% -18% based on NMMO so that a cellulose solution is formed.
- the resulting dope should contain from about 8% to about 15% cellulose.
- the heated aqueous solution 20 is then directed to a dope delivery mechanism 24, for example an extruder, where it is routed through a die block/spinnerette assembly 26.
- the die block/spinnerette assembly 26 can be directly secured to the dope delivery mechanism 24 or it can be spaced apart from the dope delivery mechanism 24.
- aqueous solution 20 consisting of cellulose 16 and a water soluble solvent 18, such as aqueous NMMO
- the apparatus and method of spinning the heated aqueous solution 20 into cellulose fibers 12 is very unique.
- very fine cellulose fibers 12 each having a diameter of less than about 5 microns at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to about 750 meters per minute.
- the die btock/spinnerette assembly 26 includes a die block 28 having a first conduit 30 formed therein through which the heated aqueous solution 20 is routed.
- the die block 28 also has at least one second conduit 32 formed therein.
- a pair of second conduits 32 is shown in a spaced apart configuration.
- Each of the second conduits 32 is sized and configured to route or direct a pressurized gas 34 therethrough.
- the pressurized gas 34 is air.
- second conduits 32 can be utilized.
- multiple spaced apart, second conduits 32 can be utilized.
- the pressurized gas 34 is normally heated to a predetermined elevated temperature.
- the pressurized gas 34 can be heated to a temperature ranging from between about 100° C to about 160° C. Desirably, the pressurized gas 34 is heated to a temperature ranging from between about 110° C to about 160° C. More desirably, the pressurized gas 34 is heated to a temperature ranging from between about 120° C to about 160° C. Most desirably, the pressurized gas 34 is heated to a temperature of about 120° C.
- the pressurized gas 34 should have a velocity of at least about 45 meters per second (m/sec.). Desirably, the pressurized gas 34 should have a velocity ranging from between about 45 m/sec. to about 500 m/sec. More desirably, the pressurized gas 34 should have a velocity ranging from between about 50 m/sec. to about 450 m/sec.
- each of the conduits 32 can vary.
- the internal diameter of each of the conduits 32, the material from which each of the conduits 32 are formed of, the back pressure on the pressurized gas 34, the temperature of the pressurized gas 34, the as well as other factors, will influence the velocity of the pressurized gas 34.
- the die block/spinnerette assembly 26 also includes a filter block 36 which is secured to the die block 28.
- the filter block 36 has at least two separate passageways 38 and 40 formed therethrough.
- the passageway 38 is sized and configured to match up and align with the first conduit 30 so that the heated aqueous solution 20 can be routed through the filter block 36.
- the other passageways 40 are sized and configured to match up and align with the two second conduits 32 so that the pressurized gas 34 can be routed through the filter block 36. It should be understood that the size and shape of the passageways 38 and 40 do not have to be identical to the size and shape of the first and second conduits, 30 and 32 respectively. However, the number of passageways 40 should be equal to the number of conduits 32 and each passageway 40 should be aligned with one of the conduits 32.
- the filter block 36 serves to filter particulate matter, such as non-dissolved pulp, solution grit, etc. from the aqueous solution 20.
- the die btock/spinnerette assembly 26 further includes a first member 42 which can be a spinnerette.
- the first member 42 is secured to the filter block 36.
- the filter block 36 is sandwiched between the die block 28 and the first member or spinnerette 42.
- the first member 42 has multiple nozzles 44 arranged in rows and/or columns or in some other desired pattern.
- Each of the nozzles 44 can be formed from a metal such as steel, stainless steel, a metal alloy, a ferrous metal, etc. Desirably, each of the nozzles 44 is formed from stainless steel.
- Each of the nozzles 44 is shown as an elongated, hollow tube 46.
- each of the hollow cylindrical tubes 46 has a longitudinal central axis X-X and a uniquely shaped cross-section. Desirably, the cross-section is circular but almost any geometrical cross-section can be utilized. The cross-section should be constant.
- Each of the hollow cylindrical tubes 46 has an inside diameter d and an outside diameter d 1 .
- the inside diameter d can range from between about 0.125 millimeters (mm) to about 1.25 mm.
- the outside diameter d 1 should be at least about 0.5 mm. Desirably, the outside diameter d 1 of each of the hollow cylindrical tubes 46 can range from between about 0.5 mm to about 2.5 mm.
- the heated aqueous solution 20 is extruded through the inside diameter d of each of the hollow cylindrical tubes 46.
- the back pressure on the heated aqueous solution 20 present in the passageway 38 of the filter block 36 or in each of the hollow cylindrical tubes 46 should be equal to or exceeds about 5 bar.
- bar it is meant a unit of pressure equal to one million (10 6 ) dynes per square centimeter.
- the back pressure on the heated aqueous solution 20 present in each of the hollow cylindrical tubes 46 can range from between about 20 bar to about 200 bar. More desirably, the back pressure on the heated aqueous solution 20 present in each of the hollow cylindrical tubes 46 can range from between about 25 bar to about 150 bar. Even more desirably, the back pressure on the heated aqueous solution 20 present in each of the hollow cylindrical tubes 46 can range from between about 30 bar to about 100 bar.
- the first member or spinnerette 42 also has at least one other passage 48 formed therein.
- Fig. 2 two spaced apart passages 48 are depicted, each of which is sized and configured to align with one of the two passageways 40 formed through the filter block 36.
- the passages 48 are connected to an enlarged chamber 50 formed on one surface of the first member or spinnerette 42.
- the enlarged chamber 50 can be centrally located about the longitudinal central axis X-X of each of the hollow cylindrical tubes 46.
- the enlarged chamber 50 is spaced away from and aligned opposite to the surface of the first member or spinnerette 42 that is secured to the filter block 36.
- the size, depth and shape of the enlarged chamber 50 can vary.
- the enlarged chamber 50 has a circular shape with a depth of at least 0.1 inches. More desirably, the enlarged chamber 50 has a circular shape with a depth of at least 0.2 inches.
- the passages 48 function to direct the pressurized gas 34 from the passageways 40 to the enlarged chamber 50 of the spinnerette 42.
- the number of passageways 40 formed in the filer block 36 can vary, the number of passages 48 formed in the first member or spinnerette 42 can also vary. Desirably, there will be an equal number of passages 48 formed in the first member or spinnerette 42 to correspond and align with the number of passageways 40 formed in the filter block 36. As stated above, better distribution of the pressurized gas 34 may be possible when a greater number of passageways 40 and passages 48 are utilized. For example, twelve passageways 40 can be formed in the filter block 36 and each can be aligned with one of the twelve passages 48 formed in the first member or spinnerette 42.
- Each of the twelve passageways 40, as well as each of the twelve passages 48, can be spaced approximately 30 degrees apart from an adjacent passageway 40 or passage 48 respectively, when viewing the filter block 36 and the first member or spinnerette 42 from one end. Better distribution of the pressurized gas 34 correlates with more uniformly formed cellulose fibers 12.
- the die block/spinnerette assembly 26 further includes a second member in the form of a gas distribution plate 52.
- the second member is secured to the first member or spinnerette 42.
- the first member or spinnerette 42 is sandwiched between the filter block 36 and the second member or gas distribution plate 52.
- the second member or gas distribution plate 52 has multiple corridors 54 formed therein.
- the second member or gas distribution plate 52 also has a chamber 56 spaced away from and aligned opposite to the surface of the second member or gas distribution plate 52 that is secured to the first member or spinnerette 42.
- the corridors 54 connect the enlarged chamber 50 to the chamber 56.
- the chamber 56 can be centrally located about the longitudinal central axis X-X of each of the hollow cylindrical tubes 46.
- the size, depth and shape of the chamber 56 can vary.
- the corridors 54 function to route the pressurized gas 34 through the second member or gas distribution plate 52.
- the second member or gas distribution plate 52 also has multiple openings 58 formed therethrough which are separate and distinct from the corridors 54.
- Each of the multiple openings 58 is sized to permit one of the multiple nozzles 44, in the form of the elongated, hollow cylindrical tubes 46, to pass therethrough.
- each of the multiple openings 58 has a circular cross-section with a diameter d 2 that is larger than the outside diameter d 1 of each of the hollow cylindrical tubes 46.
- the outside diameter d 1 of each of the hollow cylindrical tubes 46 does not form a snug or an interference fit with the inside diameter d 2 of each of the multiple openings 56.
- the die block/spinnerette assembly 26 includes a third member in the form of an exterior plate 60.
- the third member or exterior plate 60 is secured to the second member or gas distribution plate 52.
- the second member or gas distribution plate 52 is sandwiched between the first member or spinnerette 42 and the third member or exterior plate 60.
- the third member or exterior plate 60 has multiple first openings 62 formed therethrough. Each of the multiple first openings 62 is sized to freely permit one of the multiple nozzles 44, in the form of an elongated, hollow cylindrical tube 46, to pass therethrough, see Fig. 3 .
- Each of the hollow cylindrical tubes 46 can extend outward or downward beyond the third member or exterior plate 60. The distance the free end of each of the hollow cylindrical tubes 46 extends beyond the exterior plate 60 can vary. Alternatively, each of the hollow cylindrical tubes 46 can stop short of the third member or exterior plate 60.
- Each of the nozzles 44 has a first openings 62 formed adjacent thereto. Desirably, each of the first openings 62 is concentrically aligned about each of the nozzles 44.
- Each of the multiple first openings 62 can have a uniquely shaped cross-section with an inside diameter d 2 , see Fig. 3 . Desirably, each of the multiple first openings 62 has a circular cross-section.
- the inside diameter d 2 of each of the first openings 62 can vary. Desirably, each of the first openings 62 has the same inside diameter d 2 . More desirably, the inside diameter d 2 of each of the first openings 62 is at least 7.5 mm. Even more desirably, the inside diameter d 2 of each of the first openings 62 is at least 10 mm. Most desirably, the inside diameter d 2 of each of the first openings 62 is at least 12 mm.
- each of the first openings 62 should be greater than the outside diameter d 1 of each of the hollow cylindrical tubes 46.
- Each of the first openings 62 is connected to the chamber 56 formed in the second member or gas distribution plate 52.
- Each of the first openings 62 is capable of emitting pressurized gas 34 therethrough such that the pressurized gas 34 at least partially surrounds the heated aqueous solution 20 extruded from each of the nozzles 44.
- each of the first openings 62 completely surrounds the heated aqueous solution 20 extruded from each of the nozzles 44 and this pressurized air shrouds or forms a curtain around the heated aqueous solution 20 extruded from each of the nozzles 44.
- the third member or exterior plate 60 also has multiple second openings 64 formed therethrough which are connected to the chamber 56 formed in the second member or gas distribution plate 52.
- Each of the multiple second openings 64 has a uniquely shaped cross-section through which the pressurized gas 34 can be emitted.
- each of the multiple second openings 64 has a circular cross-section.
- Each of the multiple second openings 64 has an inside diameter d 3 .
- the inside diameter d 3 is of a single dimension.
- the inside diameter d 3 of each of the multiple second openings 64 can vary. Desirably, the inside diameter d 3 of each of the multiple second openings 64 is of the same dimension.
- the inside diameter d 3 of each of the second openings 64 is equal to the inside diameter d 2 of each of the first openings 62. More desirably, the inside diameter d 3 of each of the second openings 64 is at least 0.75 mm. Even more desirably, the inside diameter d 3 of each of the second openings 64 is at least 1.0 mm. Most desirably, the inside diameter d 3 of each of the second openings 64 is at least 1.2 mm.
- Each of the second openings 64 can be positioned adjacent to one of the first openings 62.
- Each of the first and second openings, 62 and 64 is aligned parallel to one another.
- two or more of each of the second openings 64 can be positioned adjacent to one of the first openings 62.
- three (3) to eight (8) of the second openings 64 can be positioned adjacent to one of the first openings 62.
- each of the second openings 64 can also be positioned adjacent to one of the nozzles 44 in each of the rows or in each of an adjacent row.
- Many different patterns or arrays can be utilized wherein the arrangement of the multiple first and second openings, 62 and 64 respectively, can be varied.
- Each of the second openings 64 is spaced from between about 1 mm to about 3.8 mm from the longitudinal central axis X 1 -X 1 of each of the nozzles 44. Desirably, each of the second openings 64 is spaced from between about 1 mm to about 2.5 mm from the longitudinal central axis X-X of each of the nozzles 44.
- each of the multiple second openings 64 can have a stationary, elongated central pin or shaft 66 positioned therein.
- the elongated central pin 66 has a constant outer diameter d 4 and is secured to the spinnerette 42, see Fig. 2 .
- the diameter d 4 of the central pin 66 can vary. Desirably, the diameter d 4 of the central pin 66 is at least 0.25 mm. More desirably, the diameter d 4 of the central pin 66 is at least 0.5 mm. Even more desirably, the diameter d 4 of the central pin 66 is at least 0.64 mm. Most desirably, the diameter d 4 of the central pin 66 is at least 0.75 mm.
- the stationary central pin 66 is shown being positioned parallel and adjacent to one of the hollow cylindrical tubes 46.
- the pressurized gas 34 can follow a straight or a circuitous route through the second member or gas distribution plate 62 and the third member or exterior plate 60 such that it will form an envelope, shroud or curtain of pressurized gas 34 around at least a portion of the circumference of the hollow cylindrical tube 46.
- shrouding it is meant something that conceals, protects, or screens.
- the pressurized gas 34 existing through the adjacent second opening 64 will provide a barrier or veil which will limit or prevent the heated aqueous solution 20, extruded out of each of the nozzles 44, i.e.
- the pressurized gas 34 emitted through the multiple second openings 64 will form pressurized gas streams which will limit or prevent individual molten filaments from joining with one or more other molten filaments and forming ropes and/or bundles.
- the pressurized gas 34 can form an envelope, shroud or curtain around the entire circumference of each of the hollow cylindrical tubes 46. The velocity and pressure of the pressurized gas 34 can be varied to suit one's equipment.
- the hollow cylindrical tube 46 extends downward beyond the first opening 62 by a vertical distance d 5 which is at least 1 mm.
- the vertical distance d 5 is at least 3 mm, and more desirably, the vertical distance d 5 is at least 5 mm.
- each of the multiple second openings 64 completely surrounds the central pin 66 such that the pressurized gas 34 can be emitted about the entire outer circumference of each of the central pins 66.
- the central pin 66 in each of the second openings 64 has a constant outer diameter d 4 .
- the central pin 66 is coaxially aligned within the second opening 64 such that a sidewall 82 of the second opening 64 is aligned parallel to the elongated central pin 66.
- the sidewall 82 is also aligned perpendicular to the second opening 64.
- an even discharge of pressurized gas 34 is emitted about the entire circumference of the central pin 66.
- a second opening 64' which has a venturi configuration, see Fig. 7 .
- venturi it is meant a constricted throat in a gas passage used to increase the velocity of the passing gas.
- Each of the multiple second openings 64' has a sidewall 84 which has a venturi shape.
- the sidewall 84 has a convex shape which can form a restricted passageway about or below the circumference of the central pin 66.
- the convex shape of the sidewall 84 increases the velocity of the pressurized gas 34 passing therethrough. In some applications, this design may be desirable.
- the terminal end of the central pin 66 is flush with the outer surface of the exterior plate 60 while in Fig. 7 , the terminal end of the central pin 66 is located inward from the outer surface of the exterior plate 60.
- the terminal end of the central pin 66 can be located within the thickness of the exterior plate 66.
- a first opening 68 is shown having a square configuration with a hollow cylindrical tube 46 positioned therein.
- a first opening 70 is shown having a triangular configuration with a hollow cylindrical tube 46 positioned therein.
- a first opening 72 is shown having of two crescent shape slots 74 spaced apart from a hollow cylindrical tube 46.
- a first opening 76 is shown having four shorter crescent shape slots 78 spaced apart from a hollow cylindrical tube 46 and from one another.
- a first opening 80 is shown having a plurality of circular holes 83 spaced apart from a hollow cylindrical tube 46.
- a first opening 80 is shown having a plurality of circular holes 83 spaced apart from a hollow cylindrical tube 46.
- ten circular holes are shown each being equally spaced apart from one another. It should be understood by one skilled in the art that the actual number of holes 83 can vary. Likewise, various arrangements for the first openings 62 can be utilized.
- an array 86 which includes a plurality of the first openings 62, each having a nozzle 44 positioned therein, and a plurality of the second openings 64 formed in the third member or exterior plate 60.
- the array 86 has a longitudinal central axis X 1 -X 1 and a transverse central axis Y 1 -Y 1 .
- the array 86 includes a plurality of columns 88 aligned parallel to the longitudinal central axis X 1 -X 1 and a plurality of rows 90 aligned parallel to the transverse central axis Y 1 -Y 1 .
- the number of columns 88 and the number of rows 90 can each vary.
- the number of columns 88 can be greater than, equal to or less than the number of rows 90. Desirably, the number of columns 88 exceeds the number of rows 90. The number of columns 88 can be an even number or an odd number. Likewise, the number of rows 90 can be an even number or an odd number. The number of columns 88 can range from between about 1 per spinnerette to about 1,000 per spinnerette. Desirably, the number of columns 88 can range from between about 2 per spinnerette to about 800 per spinnerette. More desirably, the number of columns 88 can range from between about 10 per spinnerette to about 500 per spinnerette. Even more desirably, the number of columns 88 can range from between about 20 per spinnerette to about 250 per spinnerette. In Fig. 13 , the exterior plate 60 is shown with an even number of columns 88 and an even number of rows 90.
- the number of rows 90 can range from between about 1 per spinnerette to about 100 per spinnerette. Desirably, the number of rows 90 can range from between about 2 per spinnerette to about 50 per spinnerette. More desirably, the number of rows 90 can range from between about 3 per spinnerette to about 25 per spinnerette. Even more desirably, the number of rows 90 can range from between about 6 per spinnerette to about 18 per spinnerette. Most desirably, the exterior plate 60 will contain at least about 10 rows 90 per spinnerette. In Fig. 13 , eighteen rows 90 are present.
- each of the nozzles 44 positioned in each of the columns 88, is offset or staggered from a nozzle 44 positioned in an adjacent column 88.
- staggered it is meant to place on or as if on alternating sides of a centerline; set in a zigzag row or rows.
- each of the nozzles 44, positioned in each of the rows 90 is offset or staggered from a nozzle 44 positioned in an adjacent row 90.
- at least one of the nozzles 44 in one of the columns or rows, 88 or 90 respectively is staggered from at least one of the nozzles 44 present in an adjacent column or row, 88 or 90 respectively.
- At least two of the nozzles 44 in one of the columns or rows, 88 or 90 respectively is staggered from at least two of the nozzles 44 present in an adjacent column or row, 88 or 90 respectively. Even more desirably, at least three of the nozzles 44 in one of the columns or rows, 88 or 90 respectively, is staggered from at least three of the nozzles 44 present in an adjacent column or row, 88 or 90 respectively.
- the nozzles 44 should be staggered so that as the heated aqueous cellulose solution 20 is extruded into multiple molten filaments, each of the multiple molten filaments can remain separate and distinct. By establishing a minimum distance between two adjacent nozzles 44, the molten filaments extruded therefrom will not touch or bond to one another. The staggering of the nozzles 44 also minimizes the pressurized gas streams exiting from one of the nozzles 44 from interfering with the pressurized gas streams associated with a neighboring nozzle 44.
- the third member or exterior plate 60 has at least about 8 of the first and second openings, 62 and 64 respectively, per linear centimeter.
- the number of first openings 62 can be equal to or be different from the number of second openings 64.
- the inside diameter d 2 of each of the first openings 62 can be equal to or be different from the inside diameter d 3 of the second openings 64 or 64'.
- the third member or exterior plate 60 has at least about 20 of the first and second openings, 62 and 64 respectively, per linear centimeter. More desirably, the third member or exterior plate 60 has at least about 40 of the first and second openings, 62 and 64 respectively, per linear centimeter.
- the third member or exterior plate 60 has at least about 60 of the first and second openings, 62 and 64 respectively, per linear centimeter. Most desirably, the third member or exterior plate 60 has at least about 90 of the first and second openings, 62 and 64 respectively, per linear centimeter.
- each of the rows 90 includes an equal number of the first and second openings, 62 and 64 respectively.
- each of the first openings 62 in Fig. 13 , is shown to contain a nozzle 44.
- molten filaments that can attenuate into very fine cellulose fibers.
- attenuate it is meant to make slender, fine, or small.
- molten filaments are then coagulated, as well be explained later, to form a soft, solid cellulose fiber.
- coagulate it is meant to cause a transformation of a liquid into a soft, solid mass.
- a second array 92 which includes a plurality of the first openings 62 and a plurality of the second openings 64 formed in the third member or exterior plate 60.
- Each of the first openings 62 has a nozzle 44 positioned therein.
- the array 92 has a longitudinal central axis X 2 -X 2 and a transverse central axis Y 2 -Y 2 .
- the array 92 includes a plurality of columns 94 aligned parallel to the longitudinal central axis X 2 -X 2 and a plurality of rows 96 aligned parallel to the transverse central axis Y 2 -Y 2
- the number of columns 94 and the number of rows 96 can each vary as was explained above with reference to Fig. 13 .
- One noticeable difference, between the array 86, shown in Fig. 13 , and the array 92, shown in Fig. 14 is that in the array 92, every other column 94, as well as the two outer rows 96, contains only the second openings 64. This creates a pattern wherein each of the nozzles 44 is surrounded by eight of the second openings 64.
- the outer columns 94, 94 on the left and right sides of the array 92 and the outer rows 96 on the top and bottom of the array 92 are void of the first openings 62 and the nozzles 44.
- This pattern is not required but can assist in limiting air turbulence on each end of the array 92.
- the outer two columns 94, 94 on the left side of the array, as well as the outer two rows 96, 96 on the top and bottom of the array 92 can also be made void of the first openings 62 and the nozzles 44.
- the third member or exterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively.
- each of the first openings 62 contains a nozzle 44 and each of the first openings 62 is surrounded by three of the second openings 68 through which pressurized gas is routed. This is referred to as a "three hole" pattern.
- the third member or exterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively.
- each of the first openings 62 contains a nozzle 44 and each of the first openings 62 is surrounded by four of the second openings 64 through which pressurized gas is routed.
- the third member or exterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively.
- each of the first openings 62 contains a nozzle 44 and each of the first openings 62 is surrounded by six of the second openings 64 through which pressurized gas is routed.
- Each of the second openings 64 is spaced approximately 60 degrees apart from an adjacent second opening 62. This is referred to as a "six hole” pattern.
- the third member or exterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively.
- each of the first openings 62 contains a nozzle 44 and each of the first openings 62 is surrounded by eight of the second openings 64 through which pressurized gas is routed.
- Each of the second openings 64 is spaced approximately 45 degrees apart from an adjacent second opening 62. This is referred to as an "eight hole" pattern.
- the process 10 further includes directing the heated aqueous solution 20 through each of the nozzles 44 formed in the first member or spinnerette 42.
- the first member or spinnerette 42 has multiple rows 90 of the first openings 62 each containing one of the nozzles 44.
- the first member or spinnerette 42 also has a plurality of second openings 64 formed therein.
- the first openings 62 differ from the second openings 64 in that each of the first openings 62 has a nozzle 44 positioned therein.
- at least one of the nozzles 44, located in a row 90 is staggered from at least one of the nozzles 44 located in an adjacent row 90.
- Each of the nozzles 44 is concentrically arranged within each of the first openings 62 and one or more of the second openings 64 are located adjacent to each of the nozzles 44.
- the heated aqueous solution 20 is extruded through the hollow cylindrical tube 46 of each of the nozzles 44 at a predetermined back pressure.
- the back pressure should be at least 10 bar to form a molten filament 98.
- the back pressure can range from between about 10 bar to about 200 bar as was explained earlier.
- the velocity of the heated aqueous solution 20 exiting the nozzle 44, including the adjacent air stream should be at least about 100 meters per second. Desirably, the velocity of the heated aqueous solution 20 exiting the nozzle 44, including the adjacent air stream, should be at least about 250 meters per second. More desirably, the velocity of the heated aqueous solution 20 exiting the nozzle 44 should be at least about 450 meters per second.
- the extruded molten filament 98 forms a bulge 100, see Fig. 19 , immediately upon exiting the hollow cylindrical tube 46.
- a number of factors contribute to this bulge 100 being formed. Such factors include but are not limited to: friction between the aqueous solution 20 and the inside diameter d of the hollow cylindrical tube 46, the velocity of the aqueous solution 20, the viscosity of the aqueous solution 20, the inside diameter d of the hollow cylindrical tube 46, gravity acting on the aqueous solution 20, etc.
- the extruded molten filament 98 is at least partially shrouded, and desirably, completely shrouded, by the pressurized gas 34 emitted through the first opening 62 which surrounds each of the nozzles 44.
- the pressurized gas 34 can be heated to a temperature of at least about 100° C. Desirably, the pressurized gas 34 is heated to a temperature of at least about 120° C. More desirably, the pressurized gas 34 is heated to the same temperature as that of the heated aqueous solution 20.
- the pressurized gas 34 is emitted as gas streams 102 aligned essentially parallel to the molten filament 98.
- the pressurized gas streams 102 form a veil or curtain around at least a portion of the circumference of the molten filament 98. Desirably, the pressurized gas streams 102 form a veil or curtain around the entire circumference of the molten filament 98.
- the pressurized gas 34 which is desirably air, is emitted from each of the first openings 62 at a velocity of at least 45 meters per second as was explained earlier.
- the pressurized gas streams 102 along with gravity, will attenuate and accelerate each of the molten filaments 98 into a circular cross-sectional configuration having a diameter of less than about 15 microns.
- each of the molten filaments 98 will have a diameter of from between about 0.5 microns to about 10 microns. More desirably, each of the molten filaments 98 will have a diameter of from between about 1 micron to about 8 microns. Still more desirably, each of the molten filaments 98 will have a diameter of from between about 1 micron to about 5 microns. Most desirably, each of the molten filaments 98 will have a diameter of from between about 1 micron to about 3 microns.
- the attenuation and acceleration will occur over a predetermined distance h.
- the actual amount of attenuation and the acceleration can vary. Both the amount of attenuation and the acceleration can be calculated and can be adjusted to obtain a cellulose fiber 12 having a predetermined diameter.
- the distance h can vary depending upon a number of factors, including but not limited to: the composition of the heated aqueous solution 20, the finish diameter of the cellulose fibers, the temperature of the molten filament 98, the inside diameter of the hollow cylindrical tube 46, etc.
- the distance h can range from between about 3 centimeters to about 3 meters. Desirably, the distance h should range from between about 15 centimeters to about 2 meters. More desirably, the distance h should range from between about 20 centimeters to about 1.5 meters. Even more desirably, the distance h should range from between about 30 centimeters to about 1 meter.
- the process 10 further includes extruding the heated aqueous solution 20 downward from each of the nozzles 44 parallel to a longitudinal central axis X 3 -X 3 and contacting each of the molten filaments 98 with a liquid 104.
- the liquid 104 causes each of the molten filaments 98 to coagulate into a continuous solid fiber 12.
- the liquid 104 can be water, alcohol or a solution having a high concentration of water.
- the temperature of the liquid 104 can be adjusted to suit one's particular needs. For example, the liquid 104 can be at room temperature. Alternative, the liquid 104 could be cooler than room temperature.
- the velocity of the liquid 104 can also vary.
- the liquid 104 can be introduced as a hydro jet.
- hydro jet it is meant a jet of pressurized liquid or mixture of liquid and air.
- the liquid 104 causes a major portion of the solvent 18 to solvate into the liquid solution and thus allow the molten filaments 98 to transform or coagulate into a continuous solid fiber.
- the amount of solvent 18 that is actually removed by the liquid 104 can vary depending upon the percentage of solvent 18 present in the heated aqueous solution 20. Desirably, at least 75% of the solvent present in the heated aqueous solution 20 will be removed.
- At least about 80% of the solvent present in the heated aqueous solution 20 will be removed. Even more desirably, at least about 85% of the solvent present in the heated aqueous solution 20 will be removed. Most desirably, at least about 90% of the solvent present in the heated aqueous solution 20 will be removed.
- the heated aqueous solution 20, as it leaves the nozzle 44 includes about 85% solvent, about 10% cellulose and about 5% water
- the percentages can change to about 10% solvent, about 10% cellulose and about 80% water.
- the liquid 104 can be introduced at an angle alpha ⁇ .
- the angle ⁇ can range from between about 5 degrees to about 175 degrees as measured from the longitudinal central axis X 3 -X 3 . Desirably, the angle ⁇ can range from between about 10 degrees to about 135 degrees as measured from the longitudinal central axis X 3 -X 3 . More desirably, the angle ⁇ can range from between about 25 degrees to about 90 degrees as measured from the longitudinal central axis X 3 -X 3 .
- the angle ⁇ can range from between about 30 degrees to about 60 degrees as measured from the longitudinal central axis X 3 -X 3 .
- the angle ⁇ can be an acute angle or an obtuse angle as measured from the hollow, cylindrical tube 46.
- each of the molten filaments 98 is extruded from each of the hollow cylindrical tubes 46 and each is attenuated and accelerated by the pressurized gas 34 exiting through the first openings 62 as the pressurized gas streams 102. Additional pressurized gas 34 is emitted from each of the second openings 64.
- the pressurized gas emitted from each of the second openings 64 limits or prevents each of the molten filaments 98 from physically contacting one another. This decreases the possibility that two or more of the molten filaments 98 can contact or touch one another and form ropes and/or bundles of filaments 98. It is desirable that each of the molten filaments 98 be kept separate and distinct from adjacent molten filaments 98. By doing so, one can produce a multitude of individual cellulose fibers 12 each having essentially the same diameter.
- the pressurized gas 34 emitted through each of the second openings 64 will shroud or assist in keeping adjacent molten filaments 98 separate from one another.
- the pressurized gas 34 emitted from each of the second openings 64 can also be heated so that it has an elevated temperature.
- the temperature of the pressurized gas 34 emitted from each of the second openings 64 can be equal to or closely match the temperature of the pressurized gas streams 102.
- the temperature of the pressurized gas 34 emitted from each of the second openings 64 can be at a higher or a lower temperature than the temperature of the pressurized gas streams 102.
- the velocity of the pressurized gas 34 emitted from each of the second openings 64 can be adjusted to be less than, equal to or be greater than the velocity of the pressurized gas streams 102. Desirably, the velocity of the pressurized gas 34 emitted from each of the second openings 64 is essentially equal to the velocity of the pressurized gas streams 102. Furthermore, the velocity of the pressurized gas 34 emitted from each of the first and second openings, 62 and 64 respectively, can be less than, equal to or greater than the velocity of the heated aqueous solution 20 extruded from each of the nozzles 44. Desirably, the velocity of the pressurized gas 34 emitted from each of the first and second openings, 62 and 64 respectively, is greater than the velocity of the heated aqueous solution 20 extruded from each of the nozzles 44.
- the continuous cellulose fibers 12 are still relatively soft and wet when they are collected on a moving surface 106.
- the moving surface 106 can be a conveyor belt 108, as illustrated, or be some other type of moving member, such as a rotatable drum.
- the moving surface 106 i.e. the conveyor belt 108 or the rotatable drum, can be porous so that water can easily pass therethrough.
- the moving surface 106 can be constructed so as to be able to move at different speeds.
- the loft or thickness t of the non-woven web 110 see Fig.
- the distance between the nozzles 44 and the moving surface 106 is commonly referred to in the industry as the "die to collector" distance.
- This distance denoted h 1 in Fig. 19 , can range from between about 15 centimeters to about 3 meters. Desirably, the distance h 1 is from between about 20 centimeters to about 1 meter. More desirably, the distance h 1 is from between about 25 centimeters to about 120 centimeters. Even more desirably, the distance h 1 is from between about 30 centimeters to about 90 centimeters. Most desirably, the distance h 1 is at least 50 centimeters.
- the non-woven web 110 can be constructed to have an open pore structure. The size and quantity of the pores can vary.
- the non-woven web 110 can be an entangled accumulation of the coagulated cellulose fibers 12. By “non-woven” it is meant that the fibers 12 are not arranged or weaved into a set pattern.
- the non-woven web 110 can be constructed of 100% cellulose fibers 12 or be a combination of cellulose fibers 12 and polymers fibers.
- the polymers fibers (not shown) can be extruded from another extruder which is positioned upstream or downstream from the die btock/spinnerette assembly 26, see Fig. 1 .
- the polymers fibers can be polyolefin fibers, such as polyethylene and polypropylene fibers, or they can be bicomponent fibers, etc. The percentage of the various cellulose and polymer fibers can vary to suit one's particular needs and requirements.
- cellulose fibers 12 can be combined with a polymer to form a bicomponent fiber as well.
- the process 10 can be started up by heating the aqueous solution 20 to a predetermined temperature.
- the aqueous solution 20 can be heated to an elevated temperature of from between about 80° C to about 140° C. Desirably, the aqueous solution 20 is heated to a temperature of at least 100° C. More desirably, the aqueous solution 20 is heated to a temperature of at least about 110° C. Even more desirably, the aqueous solution 20 is heated to a temperature of about 120° C.
- the pressurized gas 34 can be heated to an elevated temperature.
- the elevated temperature can be at least 100° C or higher. Desirably, the elevated temperature of the pressurized gas 34 is about 110° C.
- the elevated temperature of the pressurized gas 34 is about 120° C.
- the heated aqueous solution 20 is then directed through the die block/spinnerette assembly 26 to the fist member or spinnerette 42.
- the heated aqueous solution 20 is extruded through each of the multitude of the hollow cylindrical tubes 46 which form the nozzles 44.
- the heated aqueous solution 20 is extruded through each of the hollow cylindrical tubes 46 at a back pressure of from between about 5 bar to about 200 bar.
- the back pressure is higher than 20 bar. More desirably, the back pressure is higher than 30 bar. Even more desirably, the back pressure is higher than 40 bar.
- the heated pressurized gas 34 is simultaneously routed through each of the first and second openings, 62 and 64 respectively, at a velocity of from between about 1 meter per second to about 10 meters per second.
- the velocity of the heated pressurized gas 34 is then gradually increased until the pressurized gas 34 reaches a velocity of at least about 45 meters per second. At this time, production grade cellulose fibers 12 can be extruded.
- Shutting down the process 10 can be accomplished by turning off the heat used to heat the pressurized gas 34.
- the velocity of the pressurized gas 34 is then gradually reduced from about 45 meters per second down to 0 meters per second.
- the flow of the heated aqueous solution 20 flowing through each of the nozzles 44 is then stopped.
- the heated aqueous solution 20 is then allowed to cool down to room temperature.
- the various lines or hoses which route the heated aqueous solution 20 to the die btock/spinnerette assembly 26 can be flushed or purged. It is important to flush or purge such lines or hoses, especially if the dope delivery mechanism 24 is to be inoperative for an extended period of time.
- a coagulated cellulose fiber 12 is shown having a circular cross-sectional configuration with a diameter d 6 .
- the diameter d 6 of the cellulose fiber 12 should be less than about 15 5 microns. Desirably, the diameter d 6 of the cellulose fiber 12 is less than about 10 microns. More desirably, the diameter d 6 of the cellulose fiber 12 ranges from between about 0.5 microns to about 8 microns. Even more desirably, the diameter d 6 of the cellulose fiber 12 ranges from between about 0.5 microns to about 5 micron. Most desirably, the diameter d 6 of the cellulose fiber 12 ranges from between about 0.5 microns to about 4 microns.
- the cellulose fiber 12 has a uniformly smooth outer surface 112 when viewed at a magnification of 100X.
- the coagulated cellulose fiber 12, before contacting the moving surface 106 contains less than about 20% of the water soluble solvent 18. In other words, the concentration of the solvent 18 is measured immediately after the molten filament 98 is coagulated into a solid fiber 12.
- the coagulated cellulose fiber 12, before contacting the moving surface 106 contains less than about 15% of the water soluble solvent 18. More desirably, the coagulated cellulose fiber 12, before contacting the moving surface 106, contains less than about 10% of the water soluble solvent 18. Even more desirably, the coagulated cellulose fiber 12, before contacting the moving surface 106, contains less than about 8% of the water soluble solvent 18.
- each of the cellulose fibers 12 is formed from a heated aqueous solution 20 that can vary in composition.
- the aqueous solution 20 can include from between about 5% to about 35% cellulose, from about 60% to 90% solvent 18, and from between about 5% to about 35% water.
- the aqueous solution will contains about 10% cellulose, about 85% solvent and about 5% water.
- the most common water soluble solvent 18 is N-methyl-morpholine-N-oxide (NMMO).
- the heated aqueous solution 20 is extruded through the first member or spinnerette 42 at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to 750 meters per minute. Desirably, the heated aqueous solution 20 is extruded through the first member or spinnerette 42 at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to 750 meters per minute. More desirably, the heated aqueous solution 20 is extruded through the first member or spinnerette 42 at a throughput of greater than 1 gram/hole/minute at a production speed of up to 750 meters per minute.
- the heated aqueous solution 20 is formed into a molten filament 98.
- the molten filament 98 is attenuated and accelerated by gravity and by the adjacent pressurized gas streams 102 exiting from the first openings 62.
- Each of the molten filaments 98 are coagulated by the liquid 104 into a continuous, solid fiber 12. This solid fiber 12 is still soft and wet and contains less than 20% of the water soluble solvent 18.
- the multiple continuous cellulose fibers 12 are collected on the moving surface 106 to form the non-woven cellulose web 110.
- the non-woven cellulose 110 web contains less than about 20% solvent.
- the non-woven cellulose web 110 has a basis weight of at least about 1 gram per square meter (gsm).
- the non-woven cellulose web 110 has a basis weight of at least about 1.25 gsm.
- the non-woven cellulose web 110 has a basis weight of at least about 1.5 gsm or higher.
- the non-woven cellulose web 110 is directed to a wash station 114 where an additional liquid, desirably in the form of water, is brought into contact with the non-woven cellulose web 110.
- This additional liquid mixes with the residual solvent 18 and reduces the concentration of the solvent 18 to less than 10%.
- the concentration of the solvent 18 in the cellulose fiber 12 is reduced to less than 5%. More desirably, the concentration of the solvent 18 in the cellulose fiber 12 is reduced to less than 3%. Even more desirably, the concentration of the solvent 18 in the cellulose fiber 12 is reduced to less than 1%.
- non-woven cellulose web 110 can be subjected to additional washing stations so that over 99% of the solvent 18 is removed.
- the non-woven web 110 is dried in a dryer 116.
- the non-woven cellulose web 110 can be dried using heated air, steam, moving air, contact with another member such as a felt or a cloth, etc. Other means of drying the non-woven cellulose web 110 that are known to those skilled in the art can also be used.
- Each of the cellulose fibers 12 is white or off white in color.
- a colorant can be added to the heated aqueous solution 20 or to the molten filaments 98 to form cellulose fibers 12 of a particular color, if desired.
- the dried non-woven cellulose web 110 can be subjected to other mechanical methods, if desired.
- the non-woven cellulose web 110 can be hydroentangled.
- the non-woven cellulose web 110 can be subjected to any paper making procedure, including but not limited to: being perforated, being punched, being stamped, being embossed, being printed, being coated, etc.
- the non-woven cellulose web 110 can be wound up into a supply roll 118.
- the supply roll 118 can be loaded and transported in a semi-trailer or in a railroad car to a manufacturer, distributor or consumer, or the supply roll 118 can be stored until it is ready to be shipped to a consumer.
- an apparatus for extruding cellulose fibers.
- the apparatus includes a first member, a second member and a third member all secured together. Multiple nozzles extend outward from the first member and each is designed to direct an aqueous cellulose solution therethrough. As the aqueous solution is extruded, it is accentuated and accelerated by pressurized gas flowing through the first member and the second member and out through first openings formed in the third member. The pressurized gas at least partially surrounds each nozzle and shelters the molten filaments extruded therefrom.
- the third member also has multiple second openings formed therethrough which are also connected to a source of pressurized gas. The pressurized gas streams exiting each of the second openings function to keep each of the molten filaments from contacting an adjacent molten filament.
- a process is also disclosed of forming cellulose fibers.
- the process includes extruding an aqueous solution of cellulose and a solvent through a first member to form molten filaments.
- the first member has multiple rows of first and second openings with a nozzle positioned in each of the first openings. At least one of the nozzles in one row is staggered from at least one of the nozzles in an adjacent row. At least a portion of each of the molten filaments is shrouded in a pressurized gas emitted through each of the first openings.
- Each of the molten filaments is contacted with a liquid to remove some of the solvent and transform each of the molten filaments into a continuous solid fiber.
- the continuous solid fibers are then collected on a moving surface to form a non-woven cellulose web.
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Description
- This invention relates to an apparatus, process and an array of nozzles for extruding cellulose fibers.
- Currently, there are several different methods for extruding an aqueous solution containing cellulose and a water soluble solvent into cellulose fibers. Each of these methods utilizes special equipment to heat the aqueous solution and extrude it through a die block assembly. The die block assembly can include various components for directing and distributing the aqueous solution and pressurized gas through a plurality of nozzles to form a plurality of molten filaments. The aqueous solution is usually extruded in a downward direction such that the pressurized gas and gravity will cause the aqueous solution to attenuate into a plurality of molten filaments. The molten filaments are then contacted with a liquid which causes a major portion of the solvent to solvate into the liquid solution and thus allows the molten filaments to coagulate into solid cellulose fibers. These solid cellulose fibers are then collected on a moving surface, such as a porous conveyor belt or rotatable drum and form a non-woven web.
- Up until now, no one has been able to design and construct an apparatus or process which will allow cellulose fibers having a diameter of less than about 15 microns to be extruded and formed at a throughout that would make such a process economically feasible. In addition, no one has been able to design and construct a spinnerette that extrudes 20 or more molten filaments per linear centimeter at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to about 750 meters per minute. Furthermore, no one has been able extrude an aqueous solution containing cellulose and a solvent at back pressures of more than 20 bar without damaging the spinnerette. Still further, no one to date has been able to extrude and form very fine cellulose fibers having a diameter of less than 5 micron at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to about 750 meters per minute. Lastly, no one to date has been able to form a non-woven web constructed from such cellulose fibers which has a basis weight of less than about 1 gram per square meter at a production rate of more than about 30 meters per minute.
- International application
WO 2005/106085 A1 discloses a method and apparatus in which a cellulose solution is extruded through a first multiplicity of uniformly spaced apart nozzles and upon exiting the nozzles is accelerated and attenuated by high velocity gaseous jets to form fine cellulosic fibers. A coagulating solution is forced through a second multiplicity of nozzles uniformly spaced apart from each other and uniformly spaced apart from and generally parallel to the first multiplicity of nozzles and forming high velocity jets so that the coagulating solution impinges on the fine cellulosic fibers further attenuating them and causing them to coagulate. - Now an apparatus according to claim 1, a process according to claim 5, and a use according to claim 11 have been invented which will allow one to extrude and form cellulose fibers each having a diameter of less than about 15 microns at a throughput of greater than about 0.1 grams/hote/minute. The apparatus, process and array of nozzles is also capable of forming very fine cellulose fibers each having a diameter of less than about 5 microns at a throughput of greater than about 0.5 grams/hole/minute. Furthermore, the apparatus, process and array of nozzles produces cellulose fibers having unique characteristics that can be collected to form a non-woven web.
- Briefly, this invention relates to an apparatus, process and use of an array of nozzles for extruding cellulose fibers. The apparatus includes a first member secured to a dope delivery mechanism. The first member has multiple nozzles arranged in rows. Each of the nozzles has an inside diameter through which an aqueous solution of cellulose and a solvent can be extruded. Each of the nozzles also has at least one other passage formed therein through which a pressurized gas can be routed. The apparatus also includes a second member secured to the first member. The second member has multiple corridors formed therethrough which are connected to the passage formed in the first member, and multiple openings formed therein through which the multiple nozzles can pass. The apparatus further includes a third member secured to the second member. The third member has multiple first openings formed therethrough. Each of the multiple first openings is sized to permit one of the multiple nozzles to pass therethrough. Each of the first openings being connected to the pressurized gas corridors formed in the second member. Each of the first openings is capable of emitting pressurized gas therethrough such that the pressurized gas at least partially surrounds the aqueous solution extruded from each of the nozzles. The third member also has multiple second openings formed therethrough which are connected to the pressurized gas corridors formed in the second member. Each of the second openings is positioned adjacent to one of the nozzles, in each of the rows, and each of the second openings has an opening through which the pressurized gas can be emitted.
- The process includes the steps of forming an aqueous solution of cellulose and a solvent. This aqueous solution is directed through a spinnerette having multiple rows of nozzles and second openings. The nozzles are different from the second openings. At least one of the nozzles in one of the rows is staggered from at least one of the nozzles in an adjacent row, and each of the nozzles having a first opening aligned adjacent thereto. The aqueous solution is extruded through each of the nozzles to form multiple molten filaments. At least a portion of each of the molten filaments is shrouded in a pressurized gas emitted through the adjacent first opening. The molten filaments are then attenuated into a circular cross-sectional configuration having a diameter of less than about 5 microns. Each of the molten filaments is contacted with a liquid which chemically reacts with the solvent to remove some of the solvent whereby each of the molten filaments is transformed into a continuous solid fiber. The continuous solid fibers are then collected on a moving surface to form a non-woven cellulose web.
- Each nozzle has a longitudinal central axis and includes a hollow cylindrical tube with a predetermined cross-section. An aqueous solution of cellulose and a solvent is extruded through each of the hollow cylindrical tubes into multiple individual molten filaments. Each of the hollow cylindrical tubes is surrounded by a first opening having a uniquely shaped cross-section with a diameter. The diameter of each of the first openings is greater than the diameter of each of the hollow cylindrical tubes. Each of the first openings is capable of emitting a pressurized gas which surrounds one of the extruded molten filaments. At least three second openings are spaced outward from each of the first openings. Each of the second openings is capable of emitting a pressurized gas stream essentially parallel to the longitudinal central axis of each of the nozzles which functions to shrouds each of the extruded molten filaments.
- The general object of this invention is to provide an apparatus capable of extruding cellulose fibers having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to about 750 meters per minute. A more specific object of this invention is to provide an apparatus capable of extruding very fine cellulose fibers having a diameter of less than about 5 microns at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to about 750 meters per minute.
- Another object of this invention is to provide an apparatus for extruding cellulose fibers having a circular cross-sectional configuration and a diameter of about 5 microns or less.
- A further object of this invention is to provide an apparatus for extruding very fine cellulose fibers having a diameter of less than about 3 microns.
- Still another object of this invention is to provide an apparatus for extruding cellulose fibers which includes an array of nozzles which are capable of extruding an aqueous solution of cellulose and a water soluble solvent along with pressurized gas such that an attenuated molten filament will not adhere to an adjacent molten filament.
- Still further, an object of this invention is to provide an apparatus for extruding cellulose fibers in an economical and efficient manner.
- Another object of this invention is to provide a process of forming a non-woven cellulose web. A more specific object of this invention is to provide a non-woven cellulose web produced by such a process.
- Still another object of this invention is to provide a process of forming a web from multiple cellulose fibers each having a diameter of less than about 15 microns.
- Still another object of this invention is to provide a use of an array of nozzles for extruding multiple cellulose fibers at high speeds. A more specific object of this invention is to provide a use of an array of nozzles for extruding multiple cellulose fibers having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to about 750 meters per minute..
- Still further, an object of this invention is to provide a use of an array of nozzles for extruding multiple cellulose fibers each having a uniquely shaped cross-sectional configuration and a diameter of about 5 microns or less.
- According to an embodiment, an apparatus for extruding cellulose fibers, comprises: a) a first member having multiple nozzles arranged in rows, each of said nozzles having an inside diameter through which an aqueous solution comprised of cellulose and a solvent can be extruded, and having at least one passage formed therein through which a pressurized gas can be routed; b) a second member secured to said first member, said second member having multiple corridors formed therethrough which are connected to said at least one passage formed in said first member, and multiple openings formed therein through which said multiple nozzles can pass; and c) a third member secured to said second member, said third member having multiple first openings formed therethrough, each of said multiple first openings sized to permit one of said multiple nozzles to pass through, each of said multiple first openings being concentrically aligned about each of said multiple nozzles, each of said multiple first openings being connected to said pressurized gas corridors formed in said second member and each capable of emitting pressurized gas therethrough such that said pressurized gas at least partially surrounds said aqueous solution extruded from each of said multiple nozzles, and said third member also having multiple second openings formed therethrough which are connected to said pressurized gas corridors formed in said second member, each of said multiple second openings being positioned adjacent to one of said multiple nozzles in each of said rows, and each of said multiple second openings having a diameter through which said pressurized gas can be emitted.
- According to an embodiment, the apparatus of one of the previous embodiments is capable of forming cellulose fibers having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute, and in particular capable of forming cellulose fibers having a diameter of less than about 5 microns at a throughput of greater than 0.5 grams/hole/minute.
- According to an embodiment of the apparatus of one of the previous embodiments, said third member has an even number of rows of nozzles with at least one of said nozzles in one row being offset from one of said nozzles in an adjacent row.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said multiple hollow cylindrical tubes has an inside diameter ranging from between about 0.125 millimeters to about 01.25 millimeters.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said multiple nozzles is formed from stainless steel.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said multiple second openings has a venturi formed therein.
- According to an embodiment of the apparatus of one of the previous embodiments, said third member has an odd number of rows, and wherein at least two of said nozzles in one row are offset from two of said nozzles in an adjacent row.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said second openings contains a pin therein.
- According to an embodiment of the apparatus of one of the previous embodiments, an apparatus for extruding cellulose fibers, comprises: a) a filter block secured to a dope delivery mechanism, said filter block having a first passageway formed therein through which an aqueous solution comprised of cellulose and a solvent can be routed, and a second passageway formed therein through which a pressurized gas can be routed; b) a spinnerette secured to said filter block, said spinnerette having multiple nozzles arranged in rows, each of said nozzles having a longitudinal central axis with an inside diameter through which said aqueous solution can be extruded, and said spinnerette having at least one passage formed therethrough which is connected to said second passageway; c) a gas distribution plate secured to said spinnerette, said gas distribution plate having multiple corridors formed therethrough which are connected to said at least one passage formed in said spinnerette, and multiple openings formed therein through which said multiple nozzles can pass; and d) an exterior plate secured to said gas distribution plate, said exterior plate having multiple first openings formed therethrough, each of said multiple first openings sized to permit one of said multiple nozzles to pass through, each of said multiple first openings being concentrically aligned about each of said multiple nozzles, each of said multiple first openings being connected to said pressurized gas corridors formed in said gas distribution plate and each capable of emitting pressurized gas therethrough such that said pressurized gas at least partially surrounds said aqueous solution extruded from each of said multiple nozzles, and said exterior plate also having multiple second openings formed therethrough which are connected to said pressurized gas corridors formed in said gas distribution plate, each of said multiple second openings being positioned adjacent to one of said multiple nozzles in each of said rows, at least one of said nozzles being offset from a nozzle in an adjacent row, and each of said multiple second openings having a diameter through which said pressurized gas can be emitted.
- According to an embodiment of the apparatus of one of the previous embodiments, said exterior plate has at least three rows of nozzles with each row containing an equal number or an unequal number of said first and second openings.
- According to an embodiment of the apparatus of one of the previous embodiments, said exterior plate has at least 20 openings per linear centimeter.
- According to an embodiment, in particular of the apparatus of one of the previous embodiments, an apparatus comprises: a) a dope delivery mechanism having a first conduit formed therein through which an aqueous solution comprised of cellulose and a solvent can be routed, and a second conduit formed therein through which a pressurized gas can be routed; b) a filter block secured to said dope delivery mechanism, said filter block having at least two separate passageways formed therethrough, each of said passageways connecting with one of first and second conduits; c) a spinnerette secured to said filter block, said spinnerette having multiple nozzles arranged in rows, each of said nozzles being an elongated, hollow tube having a longitudinal central axis with a cross-section having an opening through which said aqueous solution can be extruded and having at least one passage formed therein which is connected to said pressurized gas passageway formed in said filter block; d) a gas distribution plate secured to said spinnerette, said gas distribution plate having multiple corridors formed therein which are connected to said passage formed in said spinnerette for routing said pressurized gas therethrough, and multiple openings formed therethrough each of which is sized to permit one of said multiple nozzles to pass through; and e) an exterior plate secured to said gas distribution plate, said exterior plate having multiple first openings formed therethrough, each of said multiple first openings sized to permit one of said multiple nozzles to pass through, each of said multiple first openings being concentrically aligned about each of said multiple nozzles, each of said multiple first openings being connected to said pressurized gas corridors formed in said gas distribution plate and each capable of emitting pressurized gas therethrough such that said pressurized gas at least partially surrounds said aqueous solution extruded from each of said multiple nozzles, and said exterior plate also having multiple second openings formed therethrough which are connected to said pressurized gas corridors formed in said gas distribution plate, each of said multiple second openings having a central shaft positioned therein and having a cross-section through which said pressurized gas can be emitted, and at least one of said nozzles in one of each of said rows being staggered from at least one of said nozzles in an adjacent row.
- According to an embodiment of the apparatus of one of the previous embodiments, pressurized gas can pass through said assembly at a velocity of at least 45 meters per second and each of said multiple first openings includes at least two crescent shaped slots.
- According to an embodiment of the apparatus of one of the previous embodiments, said exterior plate has at least 60 openings per linear centimeter.
- According to an embodiment, in particular of the apparatus of one of the previous embodiments, an apparatus comprises an array of nozzles for extruding multiple cellulose fibers, comprising: a) multiple nozzles each having a longitudinal central axis and each including a tube with a cross-section having a diameter through which an aqueous solution comprised of cellulose and a solvent can be extruded into a molten filament, and a first opening surrounding each of said tubes having a cross-section with a diameter, said diameter of said first opening being greater than said diameter of said tube, and each of said first openings capable of emitting a pressurized gas which surrounds one of said extruded molten filaments; and b) at least three second openings each spaced outward from each of said first openings, each of said second openings capable of emitting a pressurized gas stream essentially parallel to said longitudinal central axis of said nozzle, and each of said pressurized gas streams functioning to shroud one of said extruded molten filaments.
- According to an embodiment of the apparatus of one of the previous embodiments, said pressurized gas emitted from each of said first openings attenuates and accelerates each of said molten filaments extruded from each of said tubes into a continuous fiber having a diameter of less than about 15 microns.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said first and second openings is aligned parallel to one another.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said second openings is spaced from between about 1 millimeter to about 4 millimeters from said longitudinal central axis of said nozzle, and each of said second openings is spaced from between about 1 millimeter to about 2 millimeters from said longitudinal central axis of one of said nozzles.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said tubes extends downward beyond said first openings by at least 1 millimeter, in particular by at least 3. millimeters, and in particular by at least 5 millimeters.
- According to an embodiment, in particular of the apparatus of one of the previous embodiments, an apparatus comprises an array of nozzles comprising: a) multiple nozzles each having a longitudinal central axis and each including a hollow cylindrical tube with a cross-section having a constant diameter through which an aqueous solution comprised of cellulose and a water soluble solvent can be extruded into a molten filament, and a first opening surrounding each of said hollow cylindrical tubes and having a cross-section with a constant diameter, said diameter of each of said first openings being greater than said diameter of each of said hollow cylindrical tubes, and each of said first openings capable of emitting a pressurized gas which at least partially surrounds one of said extruded molten filaments; and b) a plurality of second openings each spaced outward from each of said first openings, each of said second openings capable of emitting a pressurized gas stream essentially parallel to said longitudinal central axis of each of said nozzles, and each of said pressurized gas streams functioning to shroud one of said extruded molten filaments.
- According to an embodiment of the apparatus of one of the previous embodiments, there are at least three second openings for each first opening and each of said second openings is equally spaced apart from an adjacent second opening.
- According to an embodiment of the apparatus of one of the previous embodiments, there are eight second openings for each first opening and each of said second openings is spaced approximately 45 degrees apart.
- According to an embodiment, in particular of the apparatus of one of the previous embodiments, an apparatus comprises an array of nozzles comprising: a) multiple nozzles arranged in rows, each of said nozzle having a longitudinal central axis and including a hollow cylindrical tube with a cross-section and having a constant diameter positioned therein through which an aqueous solution comprised of cellulose and a water soluble solvent can be extruded into a molten filament, and a first opening concentrically aligned about each of said hollow cylindrical tubes and having a cross-section with a constant diameter, said diameter of said first opening being greater than said diameter of each of said hollow cylindrical tubes, and said first opening capable of emitting pressurized gas therethrough which at least partially surrounds said extruded molten filament; b) multiple second openings arranged in said rows with said multiple nozzles, at least two of said second openings being positioned adjacent to one of said nozzles in each of said rows, each of said second openings having a pin positioned therein and having a diameter through which a pressurized gas can be emitted; and c) at least one of said nozzles in one row being offset from one of said nozzles in an adjacent row.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said first openings includes at least two crescent shaped slots spaced apart from said hollow cylindrical tube. According to an embodiment of the apparatus of one of the previous embodiments, each of said hollow cylindrical tubes is vertically spaced downward from each of said first openings by at least 3 millimeters.
- According to an embodiment of the apparatus of one of the previous embodiments, each of said second openings has a sidewall aligned perpendicular to each of said second openings.
- According to an embodiment, an process of forming a non-woven cellulose web, comprises: a) forming an aqueous solution of cellulose and a solvent; b) directing said aqueous solution through a first member having multiple rows of first and second openings, each of said first openings having a nozzle positioned therein, and at least one of said nozzles in a row being staggered from at least one of said nozzles in an adjacent row; c) extruding said aqueous solution through each of said nozzles to form multiple molten filaments; d) shrouding at least a portion of each of said molten filaments in a pressurized gas emitted through each of said adjacently aligned first and second openings; e) attenuating said molten filaments into a circular cross-sectional configuration having a diameter of less than about 15 microns; f) contacting said molten filaments with a liquid, said liquid mixing with said solvent to remove some of said solvent whereby each of said molten filaments is transformed into a continuous solid fiber, and g) collecting said continuous solid fibers on a moving surface to form a non-woven cellulose web.
- According to an embodiment the process of one of the previous embodiments comprises heating said aqueous solution to a temperature of from between about 80°C to about 140°C and heating said pressurized gas to a temperature of at least about 120 °C.
- According to an embodiment the process of one of the previous embodiments comprises extruding said aqueous solution through each of said nozzles at a throughput of greater than 0.1 grams/hole/minute. According to an embodiment the process of one of the previous embodiments comprises emitting said pressurized gas through each of said first openings at a velocity of at least 45 meters per second and each of said first openings includes at least two crescent shaped slots.
- According to an embodiment the process of one of the previous embodiments comprises emitting said pressurized gas through each of said second openings at a velocity of at least 45 meters per second.
- According to an embodiment of the process of one of the previous embodiments, said pressurized gas is pressurized air which is emitted from each of said first openings essentially parallel to said molten filament extruded through each of said nozzles, and said pressurized air accelerates and attenuates each of said molten filaments.
- According to an embodiment, the process of one of the previous embodiments comprises contacting each of said molten filaments with a liquid which causes said molten filaments to coagulate into a continuous solid fiber.
- According to an embodiment of the process of one of the previous embodiments, said liquid is water, and each of said molten filaments is contacted with said water at a distance of at least about 3 centimeters from each of said nozzle.
- According to an embodiment, the process of one of the previous embodiments comprises: a) forming an aqueous solution of cellulose and a solvent, said aqueous solution having a temperature of at least about 100 °C; b) directing said aqueous solution through a first member having multiple rows of first and second openings, each of said first openings having a nozzle positioned therein, and at least one of said nozzles in a row being staggered from at least one of said nozzles in an adjacent row, c) extruding said aqueous solution through each of said nozzles at a back pressure of at least 10 bar to form multiple molten filaments; d) shrouding at least a portion of each of said molten filaments in a pressurized gas emitted through each of said adjacently aligned first and second openings; e) attenuating said molten filaments into a circular cross-sectional configuration having a diameter of less than about 5 microns; f) contacting said molten filaments with a liquid, said liquid mixes with said solvent to remove some of said solvent whereby each of said molten filaments is transformed into a continuous solid fiber; and g) collecting said continuous solid fibers on a moving surface to form a non-woven cellulose web.
- According to an embodiment of the process of one of the previous embodiments, said pressurized gas emitted from each of said second openings prevents each of said molten filaments from physically contacting one another.
- According to an embodiment, the process of one of the previous embodiments comprises extruding said aqueous solution downward from each of said nozzles parallel to a longitudinal central axis and contacting each of said molten filaments with water introduced at an angle of from between about 5 degrees to about 175 degrees, said water causing each of said molten filaments to coagulate into a continuous solid fiber.
- According to an embodiment, the process of one of the previous embodiments comprises heating said pressurized gas to a temperature from between about 120° C to about 160° C.
- According to an embodiment of the process of one of the previous embodiments, said moving surface is a rotatable drum having a porous surface or a conveyor belt having a porous surface.
- According to an embodiment, the process of one of the previous embodiments comprises starting up said process by: a) heating said aqueous solution to a predetermined temperature above 80° C; b) directing said heated aqueous solution to said first member and extruding said heated aqueous solution through each of said nozzles at a back pressure of at least 10 bar, c) routing said pressurized gas through each of said first and second openings at a velocity of from between about 1 meter per second to about 10 meters per second; d) heating said pressurized gas to a temperature of about 100° C; and e) gradually increasing said velocity of said heated pressurized gas until said pressurized gas reaches a velocity of at least about 45 meters per second.
- According to an embodiment, the process of one of the previous embodiments comprises shutting down said process by: a) turning off said heat used to heat said pressurized gas; b) gradually reducing said velocity of said pressurized gas to 0 meters per second; c) stopping said aqueous solution from flowing through each of said nozzles; and d) allowing said aqueous solution to cool to room temperature.
- Other objects and advantages of the present invention will become more apparent to those skilled in the art in view of the following description and the accompanying drawings.
-
Fig. 1 is a schematic of a process of forming cellulose fibers. -
Fig. 2 is a cross-sectional view of a die block assembly showing multiple first and second nozzles. -
Fig. 3 is an end view of a nozzle. -
Fig. 4 is an end view of a second nozzle. -
Fig. 5 is a partial exploded view of a portion of the spinnerette body shown within the area labeled A. -
Fig. 6 is an enlarged, partial cross-sectional view of a second nozzle having a constant inside diameter. -
Fig. 7 is an enlarged, partial cross-sectional view of a second nozzle having a venturi. -
Fig. 8 is an end view of an alternative design for the first opening. -
Fig. 9 is an end view of still another embodiment for the first opening. -
Fig. 10 is an end view of a further embodiment for the first opening. -
Fig. 11 is an end view of still another embodiment for the first opening. -
Fig. 12 is an end view of still another embodiment for the first opening. -
Fig. 13 is a plane view of an array of first and second nozzles formed in an exterior plate. -
Fig. 14 is a plane view of an alternative array of first and second nozzles formed in an exterior plate. -
Fig. 15 is a plane view of an array wherein each nozzle is surrounded by three of the second openings. -
Fig. 16 is a plane view of an array wherein each nozzle is surrounded by four of the second openings. -
Fig. 17 is a plane view of an array wherein each nozzle is surrounded by six of the second openings. -
Fig. 18 is a plane view of an array wherein each nozzle is surrounded by eight of the second openings. -
Fig. 19 is an enlarged cross sectional view of a nozzle showing a molten filament being extruded therefrom. -
Fig. 20 is a plane view of a coagulated cellulose fiber. - Referring to
Fig. 1 , aprocess 10 of formingcellulose fibers 12 which can be formed into anon-woven web 14 is shown. Theprocess 10 includes the steps of combining and dissolvingcellulose 16 and a solvent 18 to form anaqueous solution 20. Theaqueous solution 20 is commonly referred to as dope in the industry. The type of raw cellulosic material used can vary. Cellulose is a complex carbohydrate C6H10O5 that is composed of glucose units which form the main constituent of the cell wall in most plants. The cellulosic material may be bleached or unbleached wood pulp which can be made by various processes of which kraft, pre-hydrolyzed kraft, and sulfite would be exemplary. Many other cellulosic raw materials, including but not limited to: purified cotton linters, plants, grasses, etc. can also be used separately or in combination with wood pulp. Thecellulose 16 can be wood pulp from any of a number of commercially available dissolving or non-dissolving grade pulps. Examples of some sources of wood pulp include: The Weyerhaeuser Company, International Paper Company, Sappi Saiccor sulfite pulp, and pre-hydrolyzed kraft pulp from International Paper Company. In addition, the wood pulp can be a high hemi-cellulose with a low degree of polymerization pulp. The cellulosic material can be chopped or shredded into a fine fluff to promote forming anaqueous solution 20 with the solvent 18. - The solvent 18 is desirably a water soluble solvent. For example, the solvent 18 can be an amine oxide, desirably a tertiary amine N-oxide containing a non-solvent for the cellulose, such as water. Representative examples of amine oxide solvents useful in the practice of this invention are set forth in
U.S. Patent 5,409,532, issued to Astegger et al . The desired solvent is N-methyl-morpholine-N-oxide (NMMO). Other representative examples of solvents include dimethylsulfoxide (DMSO), dimethylacetamide (DMAC), dimethylforamide (DMF) and caprolactan derivatives. The pulp can be dissolved in an amine oxide solvent by any art recognized means such as set forth inU.S. Patents: 4,246,221, issued to McCorsley, III ;5,330,567, issued to Zikeli et al. and5,534,113, issued to Quigley et al . Still other solvents that may be used in this invention include dilute caustic soda, phosphoric acid, a mixture of liquid ammonia/ammonia thiocynate and others. Still another way of making an aqueous solution of the cellulose is described inU.S. Patent 6,306,334 issued to Luo et al . - The
aqueous solution 20 is then heated in aheater 22 or by some other type of heating mechanism to a predetermined elevated temperature. Theaqueous solution 20 can be heated to a temperature ranging from between about 80° C to about 140° C. Desirably, theaqueous solution 20 is heated to a temperature of at least 100° C. More desirably, theaqueous solution 20 is heated to a temperature of at least about 110° C. Most desirably, theaqueous solution 20 is heated to a temperature of at least about 120° C. - The
aqueous solution 20 of thecellulose 16 and solvent 18 can be made in a known manner, for example, as taught inU.S. Patent 4,246,221, issued to McCorsley, III which is incorporated by reference and made a part hereof. InU.S. Patent 4,246,221 , the cellulose is wet in a non-solvent mixture of about 40% NMMO and 60% water. The ratio of cellulose to wet NMMO is about 1:5.1 by weight. The mixture is mixed in a double arm sigma blade mixer for about 1.3 hours under vacuum at about 120° C until sufficient water has been distilled off to leave about 12% -18% based on NMMO so that a cellulose solution is formed. The resulting dope should contain from about 8% to about 15% cellulose. - The heated
aqueous solution 20 is then directed to adope delivery mechanism 24, for example an extruder, where it is routed through a die block/spinnerette assembly 26. The die block/spinnerette assembly 26 can be directly secured to thedope delivery mechanism 24 or it can be spaced apart from thedope delivery mechanism 24. - It should be noted that even though the preparation of the
aqueous solution 20, consisting ofcellulose 16 and a water soluble solvent 18, such as aqueous NMMO, is known to those skilled in the art, the apparatus and method of spinning the heatedaqueous solution 20 intocellulose fibers 12 is very unique. Up until now, no one has been able to formcellulose fibers 12 each having a diameter of less than about 15 microns at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to about 750 meters per minute. In addition, no one has been able to form veryfine cellulose fibers 12 each having a diameter of less than about 5 microns at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to about 750 meters per minute. - Referring now to
Fig. 2 , the die btock/spinnerette assembly 26 includes adie block 28 having afirst conduit 30 formed therein through which the heatedaqueous solution 20 is routed. Thedie block 28 also has at least onesecond conduit 32 formed therein. InFig. 2 , a pair ofsecond conduits 32 is shown in a spaced apart configuration. Each of thesecond conduits 32 is sized and configured to route or direct apressurized gas 34 therethrough. Desirably, thepressurized gas 34 is air. - Those skilled in the art should understand that two, three, four or more
second conduits 32 can be utilized. For better distribution of thepressurized gas 34, multiple spaced apart,second conduits 32 can be utilized. - The
pressurized gas 34 is normally heated to a predetermined elevated temperature. Thepressurized gas 34 can be heated to a temperature ranging from between about 100° C to about 160° C. Desirably, thepressurized gas 34 is heated to a temperature ranging from between about 110° C to about 160° C. More desirably, thepressurized gas 34 is heated to a temperature ranging from between about 120° C to about 160° C. Most desirably, thepressurized gas 34 is heated to a temperature of about 120° C. Thepressurized gas 34 should have a velocity of at least about 45 meters per second (m/sec.). Desirably, thepressurized gas 34 should have a velocity ranging from between about 45 m/sec. to about 500 m/sec. More desirably, thepressurized gas 34 should have a velocity ranging from between about 50 m/sec. to about 450 m/sec. - It should be evident to one skilled in the art that the cross-sectional area, the internal shape and the internal configuration of each of the
conduits 32 can vary. The internal diameter of each of theconduits 32, the material from which each of theconduits 32 are formed of, the back pressure on thepressurized gas 34, the temperature of thepressurized gas 34, the as well as other factors, will influence the velocity of thepressurized gas 34. - The die block/
spinnerette assembly 26 also includes afilter block 36 which is secured to thedie block 28. Thefilter block 36 has at least twoseparate passageways passageway 38 is sized and configured to match up and align with thefirst conduit 30 so that the heatedaqueous solution 20 can be routed through thefilter block 36. Theother passageways 40, of which two are shown, are sized and configured to match up and align with the twosecond conduits 32 so that thepressurized gas 34 can be routed through thefilter block 36. It should be understood that the size and shape of thepassageways passageways 40 should be equal to the number ofconduits 32 and eachpassageway 40 should be aligned with one of theconduits 32. - The
filter block 36 serves to filter particulate matter, such as non-dissolved pulp, solution grit, etc. from theaqueous solution 20. - Referring to
Figs. 2 and3 , the die btock/spinnerette assembly 26 further includes afirst member 42 which can be a spinnerette. Thefirst member 42 is secured to thefilter block 36. Thefilter block 36 is sandwiched between thedie block 28 and the first member orspinnerette 42. Thefirst member 42 hasmultiple nozzles 44 arranged in rows and/or columns or in some other desired pattern. Each of thenozzles 44 can be formed from a metal such as steel, stainless steel, a metal alloy, a ferrous metal, etc. Desirably, each of thenozzles 44 is formed from stainless steel. Each of thenozzles 44 is shown as an elongated,hollow tube 46. By "tube" it is meant a hollow cylinder, especially one that conveys fluid or functions as a passage. Each of the hollowcylindrical tubes 46 has a longitudinal central axis X-X and a uniquely shaped cross-section. Desirably, the cross-section is circular but almost any geometrical cross-section can be utilized. The cross-section should be constant. Each of the hollowcylindrical tubes 46 has an inside diameter d and an outside diameter d1. The inside diameter d can range from between about 0.125 millimeters (mm) to about 1.25 mm. The outside diameter d1 should be at least about 0.5 mm. Desirably, the outside diameter d1 of each of the hollowcylindrical tubes 46 can range from between about 0.5 mm to about 2.5 mm. - The heated
aqueous solution 20 is extruded through the inside diameter d of each of the hollowcylindrical tubes 46. The back pressure on the heatedaqueous solution 20 present in thepassageway 38 of thefilter block 36 or in each of the hollowcylindrical tubes 46 should be equal to or exceeds about 5 bar. By "bar" it is meant a unit of pressure equal to one million (106) dynes per square centimeter. Desirably, the back pressure on the heatedaqueous solution 20 present in each of the hollowcylindrical tubes 46 can range from between about 20 bar to about 200 bar. More desirably, the back pressure on the heatedaqueous solution 20 present in each of the hollowcylindrical tubes 46 can range from between about 25 bar to about 150 bar. Even more desirably, the back pressure on the heatedaqueous solution 20 present in each of the hollowcylindrical tubes 46 can range from between about 30 bar to about 100 bar. - The first member or
spinnerette 42 also has at least oneother passage 48 formed therein. InFig. 2 , two spaced apartpassages 48 are depicted, each of which is sized and configured to align with one of the twopassageways 40 formed through thefilter block 36. Thepassages 48 are connected to anenlarged chamber 50 formed on one surface of the first member orspinnerette 42. Theenlarged chamber 50 can be centrally located about the longitudinal central axis X-X of each of the hollowcylindrical tubes 46. Theenlarged chamber 50 is spaced away from and aligned opposite to the surface of the first member orspinnerette 42 that is secured to thefilter block 36. The size, depth and shape of theenlarged chamber 50 can vary. Desirably, theenlarged chamber 50 has a circular shape with a depth of at least 0.1 inches. More desirably, theenlarged chamber 50 has a circular shape with a depth of at least 0.2 inches. Thepassages 48 function to direct thepressurized gas 34 from thepassageways 40 to theenlarged chamber 50 of thespinnerette 42. - It should be understood that since the number of
passageways 40 formed in thefiler block 36 can vary, the number ofpassages 48 formed in the first member orspinnerette 42 can also vary. Desirably, there will be an equal number ofpassages 48 formed in the first member orspinnerette 42 to correspond and align with the number ofpassageways 40 formed in thefilter block 36. As stated above, better distribution of thepressurized gas 34 may be possible when a greater number ofpassageways 40 andpassages 48 are utilized. For example, twelvepassageways 40 can be formed in thefilter block 36 and each can be aligned with one of the twelvepassages 48 formed in the first member orspinnerette 42. Each of the twelvepassageways 40, as well as each of the twelvepassages 48, can be spaced approximately 30 degrees apart from anadjacent passageway 40 orpassage 48 respectively, when viewing thefilter block 36 and the first member orspinnerette 42 from one end. Better distribution of thepressurized gas 34 correlates with more uniformly formedcellulose fibers 12. - Still referring to
Fig. 2 , the die block/spinnerette assembly 26 further includes a second member in the form of agas distribution plate 52. The second member is secured to the first member orspinnerette 42. The first member orspinnerette 42 is sandwiched between thefilter block 36 and the second member orgas distribution plate 52. The second member orgas distribution plate 52 hasmultiple corridors 54 formed therein. The second member orgas distribution plate 52 also has achamber 56 spaced away from and aligned opposite to the surface of the second member orgas distribution plate 52 that is secured to the first member orspinnerette 42. Thecorridors 54 connect theenlarged chamber 50 to thechamber 56. Thechamber 56 can be centrally located about the longitudinal central axis X-X of each of the hollowcylindrical tubes 46. The size, depth and shape of thechamber 56 can vary. Thecorridors 54 function to route thepressurized gas 34 through the second member orgas distribution plate 52. The second member orgas distribution plate 52 also hasmultiple openings 58 formed therethrough which are separate and distinct from thecorridors 54. Each of themultiple openings 58 is sized to permit one of themultiple nozzles 44, in the form of the elongated, hollowcylindrical tubes 46, to pass therethrough. Desirably, each of themultiple openings 58 has a circular cross-section with a diameter d2 that is larger than the outside diameter d1 of each of the hollowcylindrical tubes 46. In other words, the outside diameter d1 of each of the hollowcylindrical tubes 46 does not form a snug or an interference fit with the inside diameter d2 of each of themultiple openings 56. - It should be understood that additional smaller holes or passages can also be formed in the second member or
gas distribution plate 52 to allow pressurized gas to pass therethrough. - Referring again to
Figs. 2 and3 , the die block/spinnerette assembly 26 includes a third member in the form of anexterior plate 60. The third member orexterior plate 60 is secured to the second member orgas distribution plate 52. The second member orgas distribution plate 52 is sandwiched between the first member or spinnerette 42 and the third member orexterior plate 60. The third member orexterior plate 60 has multiplefirst openings 62 formed therethrough. Each of the multiplefirst openings 62 is sized to freely permit one of themultiple nozzles 44, in the form of an elongated, hollowcylindrical tube 46, to pass therethrough, seeFig. 3 . Each of the hollowcylindrical tubes 46 can extend outward or downward beyond the third member orexterior plate 60. The distance the free end of each of the hollowcylindrical tubes 46 extends beyond theexterior plate 60 can vary. Alternatively, each of the hollowcylindrical tubes 46 can stop short of the third member orexterior plate 60. - Each of the
nozzles 44 has afirst openings 62 formed adjacent thereto. Desirably, each of thefirst openings 62 is concentrically aligned about each of thenozzles 44. Each of the multiplefirst openings 62 can have a uniquely shaped cross-section with an inside diameter d2, seeFig. 3 . Desirably, each of the multiplefirst openings 62 has a circular cross-section. The inside diameter d2 of each of thefirst openings 62 can vary. Desirably, each of thefirst openings 62 has the same inside diameter d2. More desirably, the inside diameter d2 of each of thefirst openings 62 is at least 7.5 mm. Even more desirably, the inside diameter d2 of each of thefirst openings 62 is at least 10 mm. Most desirably, the inside diameter d2 of each of thefirst openings 62 is at least 12 mm. - The inside diameter d2 of each of the
first openings 62 should be greater than the outside diameter d1 of each of the hollowcylindrical tubes 46. Each of thefirst openings 62 is connected to thechamber 56 formed in the second member orgas distribution plate 52. Each of thefirst openings 62 is capable of emittingpressurized gas 34 therethrough such that thepressurized gas 34 at least partially surrounds the heatedaqueous solution 20 extruded from each of thenozzles 44. Desirably, each of thefirst openings 62 completely surrounds the heatedaqueous solution 20 extruded from each of thenozzles 44 and this pressurized air shrouds or forms a curtain around the heatedaqueous solution 20 extruded from each of thenozzles 44. - Referring to
Figs. 2 and4 , the third member orexterior plate 60 also has multiplesecond openings 64 formed therethrough which are connected to thechamber 56 formed in the second member orgas distribution plate 52. Each of the multiplesecond openings 64 has a uniquely shaped cross-section through which thepressurized gas 34 can be emitted. Desirably, each of the multiplesecond openings 64 has a circular cross-section. Each of the multiplesecond openings 64 has an inside diameter d3. Desirably, the inside diameter d3 is of a single dimension. The inside diameter d3 of each of the multiplesecond openings 64 can vary. Desirably, the inside diameter d3 of each of the multiplesecond openings 64 is of the same dimension. More desirably, the inside diameter d3 of each of thesecond openings 64 is equal to the inside diameter d2 of each of thefirst openings 62. More desirably, the inside diameter d3 of each of thesecond openings 64 is at least 0.75 mm. Even more desirably, the inside diameter d3 of each of thesecond openings 64 is at least 1.0 mm. Most desirably, the inside diameter d3 of each of thesecond openings 64 is at least 1.2 mm. - Each of the
second openings 64 can be positioned adjacent to one of thefirst openings 62. Each of the first and second openings, 62 and 64 is aligned parallel to one another. Alternatively, two or more of each of thesecond openings 64 can be positioned adjacent to one of thefirst openings 62. In some embodiments, three (3) to eight (8) of thesecond openings 64 can be positioned adjacent to one of thefirst openings 62. Still further, each of thesecond openings 64 can also be positioned adjacent to one of thenozzles 44 in each of the rows or in each of an adjacent row. Many different patterns or arrays can be utilized wherein the arrangement of the multiple first and second openings, 62 and 64 respectively, can be varied. - Each of the
second openings 64 is spaced from between about 1 mm to about 3.8 mm from the longitudinal central axis X1-X1 of each of thenozzles 44. Desirably, each of thesecond openings 64 is spaced from between about 1 mm to about 2.5 mm from the longitudinal central axis X-X of each of thenozzles 44. - Referring to
Figs. 2 and4 , each of the multiplesecond openings 64 can have a stationary, elongated central pin orshaft 66 positioned therein. The elongatedcentral pin 66 has a constant outer diameter d4 and is secured to thespinnerette 42, seeFig. 2 . The diameter d4 of thecentral pin 66 can vary. Desirably, the diameter d4 of thecentral pin 66 is at least 0.25 mm. More desirably, the diameter d4 of thecentral pin 66 is at least 0.5 mm. Even more desirably, the diameter d4 of thecentral pin 66 is at least 0.64 mm. Most desirably, the diameter d4 of thecentral pin 66 is at least 0.75 mm. - Referring to
Fig. 5 , the stationarycentral pin 66 is shown being positioned parallel and adjacent to one of the hollowcylindrical tubes 46. Thepressurized gas 34 can follow a straight or a circuitous route through the second member orgas distribution plate 62 and the third member orexterior plate 60 such that it will form an envelope, shroud or curtain ofpressurized gas 34 around at least a portion of the circumference of the hollowcylindrical tube 46. By "shrouding" it is meant something that conceals, protects, or screens. In addition, thepressurized gas 34 existing through the adjacentsecond opening 64 will provide a barrier or veil which will limit or prevent the heatedaqueous solution 20, extruded out of each of thenozzles 44, i.e. hollowcylindrical tubes 46, from contacting, touching and/or bonding to the heatedaqueous solution 20 extruded from anadjacent nozzle 44. By "veil" it is meant something that conceals, separates, or screens like a curtain. In short, thepressurized gas 34 emitted through the multiplesecond openings 64 will form pressurized gas streams which will limit or prevent individual molten filaments from joining with one or more other molten filaments and forming ropes and/or bundles. Desirably, thepressurized gas 34 can form an envelope, shroud or curtain around the entire circumference of each of the hollowcylindrical tubes 46. The velocity and pressure of thepressurized gas 34 can be varied to suit one's equipment. - Still referring to
Fig. 5 , one can clearly see that the hollowcylindrical tube 46 extends downward beyond thefirst opening 62 by a vertical distance d5 which is at least 1 mm. Desirably, the vertical distance d5 is at least 3 mm, and more desirably, the vertical distance d5 is at least 5 mm. - In
Figs. 4 and 5 , each of the multiplesecond openings 64 completely surrounds thecentral pin 66 such that thepressurized gas 34 can be emitted about the entire outer circumference of each of the central pins 66. One can view thepressurized gas 34 exited from each of thesecond openings 64 as shrouding or forming a veil about or around the heatedaqueous solution 20 extruded from each of thenozzles 44. - Referring now to
Figs. 6 and 7 , thecentral pin 66 in each of thesecond openings 64 has a constant outer diameter d4. InFig. 6 , thecentral pin 66 is coaxially aligned within thesecond opening 64 such that asidewall 82 of thesecond opening 64 is aligned parallel to the elongatedcentral pin 66. Thesidewall 82 is also aligned perpendicular to thesecond opening 64. In this embodiment, an even discharge ofpressurized gas 34 is emitted about the entire circumference of thecentral pin 66. Alternatively, one can utilize a second opening 64' which has a venturi configuration, seeFig. 7 . By "venturi" it is meant a constricted throat in a gas passage used to increase the velocity of the passing gas. Each of the multiple second openings 64' has asidewall 84 which has a venturi shape. For example, thesidewall 84 has a convex shape which can form a restricted passageway about or below the circumference of thecentral pin 66. The convex shape of thesidewall 84 increases the velocity of thepressurized gas 34 passing therethrough. In some applications, this design may be desirable. - It should be noted that in
Fig. 6 , the terminal end of thecentral pin 66 is flush with the outer surface of theexterior plate 60 while inFig. 7 , the terminal end of thecentral pin 66 is located inward from the outer surface of theexterior plate 60. Alternatively, the terminal end of thecentral pin 66 can be located within the thickness of theexterior plate 66. - Referring now to
Figs. 8 -12 , alternative embodiments for thefirst opening 62 are depicted. InFig. 8 , afirst opening 68 is shown having a square configuration with a hollowcylindrical tube 46 positioned therein. InFig. 9 , afirst opening 70 is shown having a triangular configuration with a hollowcylindrical tube 46 positioned therein. InFig. 10 , afirst opening 72 is shown having of twocrescent shape slots 74 spaced apart from a hollowcylindrical tube 46. InFig. 11 , afirst opening 76 is shown having four shortercrescent shape slots 78 spaced apart from a hollowcylindrical tube 46 and from one another. Lastly, inFig. 12 , afirst opening 80 is shown having a plurality ofcircular holes 83 spaced apart from a hollowcylindrical tube 46. InFig. 12 , ten circular holes are shown each being equally spaced apart from one another. It should be understood by one skilled in the art that the actual number ofholes 83 can vary. Likewise, various arrangements for thefirst openings 62 can be utilized. - Referring to
Fig. 13 , anarray 86 is shown which includes a plurality of thefirst openings 62, each having anozzle 44 positioned therein, and a plurality of thesecond openings 64 formed in the third member orexterior plate 60. Thearray 86 has a longitudinal central axis X1-X1 and a transverse central axis Y1-Y1. Thearray 86 includes a plurality ofcolumns 88 aligned parallel to the longitudinal central axis X1-X1 and a plurality ofrows 90 aligned parallel to the transverse central axis Y1-Y1. In thearray 86, the number ofcolumns 88 and the number ofrows 90 can each vary. The number ofcolumns 88 can be greater than, equal to or less than the number ofrows 90. Desirably, the number ofcolumns 88 exceeds the number ofrows 90. The number ofcolumns 88 can be an even number or an odd number. Likewise, the number ofrows 90 can be an even number or an odd number. The number ofcolumns 88 can range from between about 1 per spinnerette to about 1,000 per spinnerette. Desirably, the number ofcolumns 88 can range from between about 2 per spinnerette to about 800 per spinnerette. More desirably, the number ofcolumns 88 can range from between about 10 per spinnerette to about 500 per spinnerette. Even more desirably, the number ofcolumns 88 can range from between about 20 per spinnerette to about 250 per spinnerette. InFig. 13 , theexterior plate 60 is shown with an even number ofcolumns 88 and an even number ofrows 90. - The number of
rows 90 can range from between about 1 per spinnerette to about 100 per spinnerette. Desirably, the number ofrows 90 can range from between about 2 per spinnerette to about 50 per spinnerette. More desirably, the number ofrows 90 can range from between about 3 per spinnerette to about 25 per spinnerette. Even more desirably, the number ofrows 90 can range from between about 6 per spinnerette to about 18 per spinnerette. Most desirably, theexterior plate 60 will contain at least about 10rows 90 per spinnerette. InFig. 13 , eighteenrows 90 are present - One will also notice that each of the
nozzles 44, positioned in each of thecolumns 88, is offset or staggered from anozzle 44 positioned in anadjacent column 88. By "staggered" it is meant to place on or as if on alternating sides of a centerline; set in a zigzag row or rows. Likewise, each of thenozzles 44, positioned in each of therows 90, is offset or staggered from anozzle 44 positioned in anadjacent row 90. Desirably, at least one of thenozzles 44 in one of the columns or rows, 88 or 90 respectively, is staggered from at least one of thenozzles 44 present in an adjacent column or row, 88 or 90 respectively. More desirably, at least two of thenozzles 44 in one of the columns or rows, 88 or 90 respectively, is staggered from at least two of thenozzles 44 present in an adjacent column or row, 88 or 90 respectively. Even more desirably, at least three of thenozzles 44 in one of the columns or rows, 88 or 90 respectively, is staggered from at least three of thenozzles 44 present in an adjacent column or row, 88 or 90 respectively. - It has been recognized that in order to achieve uniform and high quality formation of the
cellulose fibers 12, thenozzles 44 should be staggered so that as the heatedaqueous cellulose solution 20 is extruded into multiple molten filaments, each of the multiple molten filaments can remain separate and distinct. By establishing a minimum distance between twoadjacent nozzles 44, the molten filaments extruded therefrom will not touch or bond to one another. The staggering of thenozzles 44 also minimizes the pressurized gas streams exiting from one of thenozzles 44 from interfering with the pressurized gas streams associated with a neighboringnozzle 44. - Still referring to
Fig. 13 , the third member orexterior plate 60 has at least about 8 of the first and second openings, 62 and 64 respectively, per linear centimeter. The number offirst openings 62 can be equal to or be different from the number ofsecond openings 64. The inside diameter d2 of each of thefirst openings 62 can be equal to or be different from the inside diameter d3 of thesecond openings 64 or 64'. Desirably, the third member orexterior plate 60 has at least about 20 of the first and second openings, 62 and 64 respectively, per linear centimeter. More desirably, the third member orexterior plate 60 has at least about 40 of the first and second openings, 62 and 64 respectively, per linear centimeter. Still more desirably, the third member orexterior plate 60 has at least about 60 of the first and second openings, 62 and 64 respectively, per linear centimeter. Most desirably, the third member orexterior plate 60 has at least about 90 of the first and second openings, 62 and 64 respectively, per linear centimeter. - It should be apparent to one skilled in the art that many different arrays can be constructed and utilized. For example, one could form an array in the third member or
exterior plate 60 that has at least sixrows 90 per spinnerette and each of therows 90 includes an equal number of the first and second openings, 62 and 64 respectively. Alternatively, one could form an array in the third member orexterior plate 60 that has at least tenrows 90 per spinnerette and each of therows 90 includes at least two of thefirst openings 62, i.e. two of thenozzles 44, and at least two of thesecond openings 68. Furthermore, one could form an array in the third member orexterior plate 60 that has at least tenrows 90 per spinnerette and each of therows 90 contains an unequal number of the first and second openings, 62 and 64 respectively. - Regardless of the particular array one selects, it should be noted that by offsetting one of the
first openings 62, with one of thenozzles 44 located therein, in one of thecolumns 88 orrows 90, from one of thefirst openings 62 present in anadjacent column 88 orrow 90, one can increase the distance between adjacentfirst openings 62. Likewise, the distance between twoadjacent nozzles 44 is also increased. As this distance is increased, the likelihood that a molten filament extruded from one of thenozzles 44 will contact or touch a molten filament extruded from theadjacent nozzle 44 is decreased. Each of thefirst openings 62, inFig. 13 , is shown to contain anozzle 44. By limiting or preventing such contact, one can form individual molten filaments that can attenuate into very fine cellulose fibers. By "attenuate" it is meant to make slender, fine, or small. Each of the molten filaments are then coagulated, as well be explained later, to form a soft, solid cellulose fiber. By "coagulate" it is meant to cause a transformation of a liquid into a soft, solid mass. - Referring now to
Fig. 14 , asecond array 92 is shown which includes a plurality of thefirst openings 62 and a plurality of thesecond openings 64 formed in the third member orexterior plate 60. Each of thefirst openings 62 has anozzle 44 positioned therein. Thearray 92 has a longitudinal central axis X2-X2 and a transverse central axis Y2-Y2. Thearray 92 includes a plurality ofcolumns 94 aligned parallel to the longitudinal central axis X2-X2 and a plurality ofrows 96 aligned parallel to the transverse central axis Y2-Y2 In thearray 92, the number ofcolumns 94 and the number ofrows 96 can each vary as was explained above with reference toFig. 13 . One noticeable difference, between thearray 86, shown inFig. 13 , and thearray 92, shown inFig. 14 , is that in thearray 92, everyother column 94, as well as the twoouter rows 96, contains only thesecond openings 64. This creates a pattern wherein each of thenozzles 44 is surrounded by eight of thesecond openings 64. This means that eight pressurized gas streams are present to separate and shroud each molten filament extruded from each of thenozzles 44 from contacting or touching an adjacent molten filament. By keeping each molten filament separate, one can limit or eliminate roping and/or bundling of the molten filaments and thereby obtain multiple fine cellulose fibers. - Still referring to
Fig. 14 , one will also notice that theouter columns array 92 and theouter rows 96 on the top and bottom of thearray 92 are void of thefirst openings 62 and thenozzles 44. This pattern is not required but can assist in limiting air turbulence on each end of thearray 92. In addition, one can further limit air turbulence by making the twocolumns first openings 62 and thenozzles 44, as shown. Likewise, the outer twocolumns rows array 92 can also be made void of thefirst openings 62 and thenozzles 44. - Referring to
Figs. 15 - 18 , four different arrays are depicted. InFig. 15 , the third member orexterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively. In this array, each of thefirst openings 62 contains anozzle 44 and each of thefirst openings 62 is surrounded by three of thesecond openings 68 through which pressurized gas is routed. This is referred to as a "three hole" pattern. InFig. 16 , the third member orexterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively. In this array, each of thefirst openings 62 contains anozzle 44 and each of thefirst openings 62 is surrounded by four of thesecond openings 64 through which pressurized gas is routed. This is referred to as a "four hole" pattern. InFig. 17 , the third member orexterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively. In this array, each of thefirst openings 62 contains anozzle 44 and each of thefirst openings 62 is surrounded by six of thesecond openings 64 through which pressurized gas is routed. Each of thesecond openings 64 is spaced approximately 60 degrees apart from an adjacentsecond opening 62. This is referred to as a "six hole" pattern. InFig. 18 , the third member orexterior plate 60 contains a plurality of first and second openings, 62 and 64 respectively. In this array, each of thefirst openings 62 contains anozzle 44 and each of thefirst openings 62 is surrounded by eight of thesecond openings 64 through which pressurized gas is routed. Each of thesecond openings 64 is spaced approximately 45 degrees apart from an adjacentsecond opening 62. This is referred to as an "eight hole" pattern. - Referring to
Figs. 1 ,13 and19 , theprocess 10 further includes directing the heatedaqueous solution 20 through each of thenozzles 44 formed in the first member orspinnerette 42. The first member orspinnerette 42 hasmultiple rows 90 of thefirst openings 62 each containing one of thenozzles 44. The first member orspinnerette 42 also has a plurality ofsecond openings 64 formed therein. Thefirst openings 62 differ from thesecond openings 64 in that each of thefirst openings 62 has anozzle 44 positioned therein. In the first member orspinnerette 42, at least one of thenozzles 44, located in arow 90, is staggered from at least one of thenozzles 44 located in anadjacent row 90. Each of thenozzles 44 is concentrically arranged within each of thefirst openings 62 and one or more of thesecond openings 64 are located adjacent to each of thenozzles 44. - The heated
aqueous solution 20 is extruded through the hollowcylindrical tube 46 of each of thenozzles 44 at a predetermined back pressure. The back pressure should be at least 10 bar to form amolten filament 98. The back pressure can range from between about 10 bar to about 200 bar as was explained earlier. The velocity of the heatedaqueous solution 20 exiting thenozzle 44, including the adjacent air stream, should be at least about 100 meters per second. Desirably, the velocity of the heatedaqueous solution 20 exiting thenozzle 44, including the adjacent air stream, should be at least about 250 meters per second. More desirably, the velocity of the heatedaqueous solution 20 exiting thenozzle 44 should be at least about 450 meters per second. The extrudedmolten filament 98 forms abulge 100, seeFig. 19 , immediately upon exiting the hollowcylindrical tube 46. A number of factors contribute to thisbulge 100 being formed. Such factors include but are not limited to: friction between theaqueous solution 20 and the inside diameter d of the hollowcylindrical tube 46, the velocity of theaqueous solution 20, the viscosity of theaqueous solution 20, the inside diameter d of the hollowcylindrical tube 46, gravity acting on theaqueous solution 20, etc. - The extruded
molten filament 98 is at least partially shrouded, and desirably, completely shrouded, by thepressurized gas 34 emitted through thefirst opening 62 which surrounds each of thenozzles 44. Thepressurized gas 34 can be heated to a temperature of at least about 100° C. Desirably, thepressurized gas 34 is heated to a temperature of at least about 120° C. More desirably, thepressurized gas 34 is heated to the same temperature as that of the heatedaqueous solution 20. Thepressurized gas 34 is emitted asgas streams 102 aligned essentially parallel to themolten filament 98. Thepressurized gas streams 102 form a veil or curtain around at least a portion of the circumference of themolten filament 98. Desirably, thepressurized gas streams 102 form a veil or curtain around the entire circumference of themolten filament 98. Thepressurized gas 34, which is desirably air, is emitted from each of thefirst openings 62 at a velocity of at least 45 meters per second as was explained earlier. Thepressurized gas streams 102, along with gravity, will attenuate and accelerate each of themolten filaments 98 into a circular cross-sectional configuration having a diameter of less than about 15 microns. Desirably, each of themolten filaments 98 will have a diameter of from between about 0.5 microns to about 10 microns. More desirably, each of themolten filaments 98 will have a diameter of from between about 1 micron to about 8 microns. Still more desirably, each of themolten filaments 98 will have a diameter of from between about 1 micron to about 5 microns. Most desirably, each of themolten filaments 98 will have a diameter of from between about 1 micron to about 3 microns. - Still referring to
Fig. 19 , the attenuation and acceleration will occur over a predetermined distance h. The actual amount of attenuation and the acceleration can vary. Both the amount of attenuation and the acceleration can be calculated and can be adjusted to obtain acellulose fiber 12 having a predetermined diameter. The distance h can vary depending upon a number of factors, including but not limited to: the composition of the heatedaqueous solution 20, the finish diameter of the cellulose fibers, the temperature of themolten filament 98, the inside diameter of the hollowcylindrical tube 46, etc. The distance h can range from between about 3 centimeters to about 3 meters. Desirably, the distance h should range from between about 15 centimeters to about 2 meters. More desirably, the distance h should range from between about 20 centimeters to about 1.5 meters. Even more desirably, the distance h should range from between about 30 centimeters to about 1 meter. - The
process 10 further includes extruding the heatedaqueous solution 20 downward from each of thenozzles 44 parallel to a longitudinal central axis X3-X3 and contacting each of themolten filaments 98 with a liquid 104. The liquid 104 causes each of themolten filaments 98 to coagulate into a continuoussolid fiber 12. The liquid 104 can be water, alcohol or a solution having a high concentration of water. The temperature of the liquid 104 can be adjusted to suit one's particular needs. For example, the liquid 104 can be at room temperature. Alternative, the liquid 104 could be cooler than room temperature. The velocity of the liquid 104 can also vary. It has been found in some applications that using apressurized liquid 104 produces a better chemical reaction between themolten filaments 98 and the liquid 104. For example, the liquid 104 can be introduced as a hydro jet. By "hydro jet" it is meant a jet of pressurized liquid or mixture of liquid and air. The liquid 104 causes a major portion of the solvent 18 to solvate into the liquid solution and thus allow themolten filaments 98 to transform or coagulate into a continuous solid fiber. The amount of solvent 18 that is actually removed by the liquid 104 can vary depending upon the percentage of solvent 18 present in the heatedaqueous solution 20. Desirably, at least 75% of the solvent present in the heatedaqueous solution 20 will be removed. More desirably, at least about 80% of the solvent present in the heatedaqueous solution 20 will be removed. Even more desirably, at least about 85% of the solvent present in the heatedaqueous solution 20 will be removed. Most desirably, at least about 90% of the solvent present in the heatedaqueous solution 20 will be removed. - For example, if the heated
aqueous solution 20, as it leaves thenozzle 44, includes about 85% solvent, about 10% cellulose and about 5% water, then once themolten filament 98 is contacted with the liquid 104, the percentages can change to about 10% solvent, about 10% cellulose and about 80% water. In order to remove all of the solvent 18 that is present in each of themolten filaments 98, one will normally have to subject thecellulose fibers 12 to additional washing steps. - Each of the
molten filaments 98 should be contacted with the liquid 104 at a distance h of at least about 3 centimeters from each of thenozzles 44. The liquid 104 can be introduced at an angle alpha α. The angle α can range from between about 5 degrees to about 175 degrees as measured from the longitudinal central axis X3-X3. Desirably, the angle α can range from between about 10 degrees to about 135 degrees as measured from the longitudinal central axis X3-X3. More desirably, the angle α can range from between about 25 degrees to about 90 degrees as measured from the longitudinal central axis X3-X3. Even more desirably, the angle α can range from between about 30 degrees to about 60 degrees as measured from the longitudinal central axis X3-X3. The angle α can be an acute angle or an obtuse angle as measured from the hollow,cylindrical tube 46. - Referring again to
Figs. 2 and19 , as each of themolten filaments 98 is extruded from each of the hollowcylindrical tubes 46 and each is attenuated and accelerated by thepressurized gas 34 exiting through thefirst openings 62 as the pressurized gas streams 102. Additionalpressurized gas 34 is emitted from each of thesecond openings 64. The pressurized gas emitted from each of thesecond openings 64 limits or prevents each of themolten filaments 98 from physically contacting one another. This decreases the possibility that two or more of themolten filaments 98 can contact or touch one another and form ropes and/or bundles offilaments 98. It is desirable that each of themolten filaments 98 be kept separate and distinct from adjacentmolten filaments 98. By doing so, one can produce a multitude ofindividual cellulose fibers 12 each having essentially the same diameter. - The
pressurized gas 34 emitted through each of thesecond openings 64 will shroud or assist in keeping adjacentmolten filaments 98 separate from one another. Thepressurized gas 34 emitted from each of thesecond openings 64 can also be heated so that it has an elevated temperature. The temperature of thepressurized gas 34 emitted from each of thesecond openings 64 can be equal to or closely match the temperature of the pressurized gas streams 102. Alternatively, the temperature of thepressurized gas 34 emitted from each of thesecond openings 64 can be at a higher or a lower temperature than the temperature of the pressurized gas streams 102. - Likewise, the velocity of the
pressurized gas 34 emitted from each of thesecond openings 64 can be adjusted to be less than, equal to or be greater than the velocity of the pressurized gas streams 102. Desirably, the velocity of thepressurized gas 34 emitted from each of thesecond openings 64 is essentially equal to the velocity of the pressurized gas streams 102. Furthermore, the velocity of thepressurized gas 34 emitted from each of the first and second openings, 62 and 64 respectively, can be less than, equal to or greater than the velocity of the heatedaqueous solution 20 extruded from each of thenozzles 44. Desirably, the velocity of thepressurized gas 34 emitted from each of the first and second openings, 62 and 64 respectively, is greater than the velocity of the heatedaqueous solution 20 extruded from each of thenozzles 44. - Still referring to
Figs. 1 and19 , thecontinuous cellulose fibers 12 are still relatively soft and wet when they are collected on a movingsurface 106. The movingsurface 106 can be aconveyor belt 108, as illustrated, or be some other type of moving member, such as a rotatable drum. The movingsurface 106, i.e. theconveyor belt 108 or the rotatable drum, can be porous so that water can easily pass therethrough. The movingsurface 106 can be constructed so as to be able to move at different speeds. As the continuous, coagulatedcellulose fibers 12 contact the movingsurface 106 they will accumulate to form anon-woven web 110. The loft or thickness t of thenon-woven web 110, seeFig. 19 , will vary depending upon the speed of the movingsurface 106. For example, the slower the speed of the movingsurface 106, the greater the loft or thickness t of thenon-woven web 110 will be. Likewise, as the speed of the movingsurface 106 is increased, the loft or thickness of thenon-woven web 110 will decrease. - The distance between the
nozzles 44 and the movingsurface 106 is commonly referred to in the industry as the "die to collector" distance. This distance, denoted h1 inFig. 19 , can range from between about 15 centimeters to about 3 meters. Desirably, the distance h1 is from between about 20 centimeters to about 1 meter. More desirably, the distance h1 is from between about 25 centimeters to about 120 centimeters. Even more desirably, the distance h1 is from between about 30 centimeters to about 90 centimeters. Most desirably, the distance h1 is at least 50 centimeters. - The
non-woven web 110 can be constructed to have an open pore structure. The size and quantity of the pores can vary. Thenon-woven web 110 can be an entangled accumulation of the coagulatedcellulose fibers 12. By "non-woven" it is meant that thefibers 12 are not arranged or weaved into a set pattern. Thenon-woven web 110 can be constructed of 100% cellulose fibers 12 or be a combination ofcellulose fibers 12 and polymers fibers. The polymers fibers (not shown) can be extruded from another extruder which is positioned upstream or downstream from the die btock/spinnerette assembly 26, seeFig. 1 . The polymers fibers can be polyolefin fibers, such as polyethylene and polypropylene fibers, or they can be bicomponent fibers, etc. The percentage of the various cellulose and polymer fibers can vary to suit one's particular needs and requirements. - It should be understood that the
cellulose fibers 12 can be combined with a polymer to form a bicomponent fiber as well. - The
process 10 can be started up by heating theaqueous solution 20 to a predetermined temperature. Theaqueous solution 20 can be heated to an elevated temperature of from between about 80° C to about 140° C. Desirably, theaqueous solution 20 is heated to a temperature of at least 100° C. More desirably, theaqueous solution 20 is heated to a temperature of at least about 110° C. Even more desirably, theaqueous solution 20 is heated to a temperature of about 120° C. Simultaneously or sequentially, thepressurized gas 34 can be heated to an elevated temperature. The elevated temperature can be at least 100° C or higher. Desirably, the elevated temperature of thepressurized gas 34 is about 110° C. More desirably, the elevated temperature of thepressurized gas 34 is about 120° C. The heatedaqueous solution 20 is then directed through the die block/spinnerette assembly 26 to the fist member orspinnerette 42. At the first member orspinnerette 42, the heatedaqueous solution 20 is extruded through each of the multitude of the hollowcylindrical tubes 46 which form thenozzles 44. The heatedaqueous solution 20 is extruded through each of the hollowcylindrical tubes 46 at a back pressure of from between about 5 bar to about 200 bar. Desirably, the back pressure is higher than 20 bar. More desirably, the back pressure is higher than 30 bar. Even more desirably, the back pressure is higher than 40 bar. The heatedpressurized gas 34 is simultaneously routed through each of the first and second openings, 62 and 64 respectively, at a velocity of from between about 1 meter per second to about 10 meters per second. The velocity of the heatedpressurized gas 34 is then gradually increased until thepressurized gas 34 reaches a velocity of at least about 45 meters per second. At this time, productiongrade cellulose fibers 12 can be extruded. - Shutting down the
process 10 can be accomplished by turning off the heat used to heat thepressurized gas 34. The velocity of thepressurized gas 34 is then gradually reduced from about 45 meters per second down to 0 meters per second. The flow of the heatedaqueous solution 20 flowing through each of thenozzles 44 is then stopped. The heatedaqueous solution 20 is then allowed to cool down to room temperature. At this time the various lines or hoses which route the heatedaqueous solution 20 to the die btock/spinnerette assembly 26 can be flushed or purged. It is important to flush or purge such lines or hoses, especially if thedope delivery mechanism 24 is to be inoperative for an extended period of time. - Referring to
Fig. 20 , a coagulatedcellulose fiber 12 is shown having a circular cross-sectional configuration with a diameter d6. The diameter d6 of thecellulose fiber 12 should be less than about 15 5 microns. Desirably, the diameter d6 of thecellulose fiber 12 is less than about 10 microns. More desirably, the diameter d6 of thecellulose fiber 12 ranges from between about 0.5 microns to about 8 microns. Even more desirably, the diameter d6 of thecellulose fiber 12 ranges from between about 0.5 microns to about 5 micron. Most desirably, the diameter d6 of thecellulose fiber 12 ranges from between about 0.5 microns to about 4 microns. - The
cellulose fiber 12 has a uniformly smoothouter surface 112 when viewed at a magnification of 100X. The coagulatedcellulose fiber 12, before contacting the movingsurface 106, contains less than about 20% of the water soluble solvent 18. In other words, the concentration of the solvent 18 is measured immediately after themolten filament 98 is coagulated into asolid fiber 12. Desirably, the coagulatedcellulose fiber 12, before contacting the movingsurface 106, contains less than about 15% of the water soluble solvent 18. More desirably, the coagulatedcellulose fiber 12, before contacting the movingsurface 106, contains less than about 10% of the water soluble solvent 18. Even more desirably, the coagulatedcellulose fiber 12, before contacting the movingsurface 106, contains less than about 8% of the water soluble solvent 18. - As mentioned above, each of the
cellulose fibers 12 is formed from a heatedaqueous solution 20 that can vary in composition. Theaqueous solution 20 can include from between about 5% to about 35% cellulose, from about 60% to 90% solvent 18, and from between about 5% to about 35% water. Typically, the aqueous solution will contains about 10% cellulose, about 85% solvent and about 5% water. The most common water soluble solvent 18 is N-methyl-morpholine-N-oxide (NMMO). - The heated
aqueous solution 20 is extruded through the first member orspinnerette 42 at a throughput of greater than 0.1 grams/hole/minute at a production speed of up to 750 meters per minute. Desirably, the heatedaqueous solution 20 is extruded through the first member orspinnerette 42 at a throughput of greater than 0.5 grams/hole/minute at a production speed of up to 750 meters per minute. More desirably, the heatedaqueous solution 20 is extruded through the first member orspinnerette 42 at a throughput of greater than 1 gram/hole/minute at a production speed of up to 750 meters per minute. Immediately after being extruded from each of thenozzles 44, the heatedaqueous solution 20 is formed into amolten filament 98. Themolten filament 98 is attenuated and accelerated by gravity and by the adjacentpressurized gas streams 102 exiting from thefirst openings 62. Each of themolten filaments 98 are coagulated by the liquid 104 into a continuous,solid fiber 12. Thissolid fiber 12 is still soft and wet and contains less than 20% of the water soluble solvent 18. - Referring again to
Fig. 1 , the multiplecontinuous cellulose fibers 12 are collected on the movingsurface 106 to form thenon-woven cellulose web 110. Thenon-woven cellulose 110 web contains less than about 20% solvent. Thenon-woven cellulose web 110 has a basis weight of at least about 1 gram per square meter (gsm). Alternatively, thenon-woven cellulose web 110 has a basis weight of at least about 1.25 gsm. Still alternatively, thenon-woven cellulose web 110 has a basis weight of at least about 1.5 gsm or higher. - The
non-woven cellulose web 110 is directed to awash station 114 where an additional liquid, desirably in the form of water, is brought into contact with thenon-woven cellulose web 110. This additional liquid mixes with the residual solvent 18 and reduces the concentration of the solvent 18 to less than 10%. Desirably, the concentration of the solvent 18 in thecellulose fiber 12 is reduced to less than 5%. More desirably, the concentration of the solvent 18 in thecellulose fiber 12 is reduced to less than 3%. Even more desirably, the concentration of the solvent 18 in thecellulose fiber 12 is reduced to less than 1%. - It should be noted that the
non-woven cellulose web 110 can be subjected to additional washing stations so that over 99% of the solvent 18 is removed. - After the concentration of the solvent 18 has been reduced to a preselected value or until essentially all of the solvent 18 is removed from the
non-woven cellulose web 110, thenon-woven web 110 is dried in adryer 116. Thenon-woven cellulose web 110 can be dried using heated air, steam, moving air, contact with another member such as a felt or a cloth, etc. Other means of drying thenon-woven cellulose web 110 that are known to those skilled in the art can also be used. - Each of the
cellulose fibers 12 is white or off white in color. A colorant can be added to the heatedaqueous solution 20 or to themolten filaments 98 to formcellulose fibers 12 of a particular color, if desired. - The dried
non-woven cellulose web 110 can be subjected to other mechanical methods, if desired. For example, thenon-woven cellulose web 110 can be hydroentangled. Furthermore, thenon-woven cellulose web 110 can be subjected to any paper making procedure, including but not limited to: being perforated, being punched, being stamped, being embossed, being printed, being coated, etc. After being so treated, thenon-woven cellulose web 110 can be wound up into asupply roll 118. Thesupply roll 118 can be loaded and transported in a semi-trailer or in a railroad car to a manufacturer, distributor or consumer, or thesupply roll 118 can be stored until it is ready to be shipped to a consumer. - While the invention has been described in conjunction with several specific embodiments, it is to be understood that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, this invention is intended to embrace all such alternatives, modifications and variations which fall within the spirit and scope of the appended claims.
- Summarized, an apparatus is disclosed for extruding cellulose fibers. The apparatus includes a first member, a second member and a third member all secured together. Multiple nozzles extend outward from the first member and each is designed to direct an aqueous cellulose solution therethrough. As the aqueous solution is extruded, it is accentuated and accelerated by pressurized gas flowing through the first member and the second member and out through first openings formed in the third member. The pressurized gas at least partially surrounds each nozzle and shelters the molten filaments extruded therefrom. The third member also has multiple second openings formed therethrough which are also connected to a source of pressurized gas. The pressurized gas streams exiting each of the second openings function to keep each of the molten filaments from contacting an adjacent molten filament.
- A process is also disclosed of forming cellulose fibers. The process includes extruding an aqueous solution of cellulose and a solvent through a first member to form molten filaments. The first member has multiple rows of first and second openings with a nozzle positioned in each of the first openings. At least one of the nozzles in one row is staggered from at least one of the nozzles in an adjacent row. At least a portion of each of the molten filaments is shrouded in a pressurized gas emitted through each of the first openings. Each of the molten filaments is contacted with a liquid to remove some of the solvent and transform each of the molten filaments into a continuous solid fiber. The continuous solid fibers are then collected on a moving surface to form a non-woven cellulose web.
Claims (16)
- An apparatus (26) for extruding cellulose fibers (12), comprising:a) a first member (42) having multiple nozzles (44) arranged in rows, each of said nozzles (44) having an inside diameter through which an aqueous solution (20) comprised of cellulose (16) and a solvent (18) can be extruded, and at least one passage (48) formed through said first member (42) through which a pressurized gas (34) can be routed;b) a second member (52) secured to said first member (42), said second member (52) having multiple corridors (54) formed therethrough which are connected to said at least one passage (48) formed in said first member (42), and multiple openings (58) formed through said second member (52) through which each of said multiple nozzles (44) can pass; andc) a third member (60) secured to said second member (52), said third member (60) having multiple first openings (62) formed therethrough, each of said multiple first openings (62) sized to permit one of said multiple nozzles (44) to pass through, each of said multiple first openings (62) being concentrically aligned about each of said multiple nozzles (44), each of said multiple first openings (62) being connected to said pressurized gas corridors (54) formed in said second member (52) and each capable of emitting pressurized gas (34) therethrough such that said pressurized gas (34) at least partially surrounds said aqueous solution (20) extruded from each of said multiple nozzles (44), and said third member (60) also having multiple second openings (64) formed therethrough which are connected to said pressurized gas corridors (54) formed in said second member (52), each of said multiple second openings (64) being positioned adjacent to one of said multiple nozzles (44), and each of said multiple second openings (64) having a diameter through which said pressurized gas (34) can be emitted,characterized in that
multiple pins (66) are arranged adjacent to said multiple nozzles (44), each of said multiple pins (66) passing through one of said multiple corridors (54) and each of said multiple second openings (64) being larger than each of said multiple pins (66). - The apparatus of claim 1, further comprising a filter block (36) secured between a die block (28) and said first member (42), said filter block (36) having a first passageway (38) formed therein through which an aqueous solution (20) comprised of cellulose (16) and a solvent (18) can be routed, and a second passageway (40) formed therein through which a pressurized gas (34) can be routed.
- The apparatus (26) of claim 2, wherein said die block (28) has a first conduit (30) formed therein through which an aqueous solution (20) comprised of cellulose (16) and a solvent (18) can be routed, and a second conduit (32) formed therein through which a pressurized gas (34) can be routed, and said pressurized gas (34) can pass through said apparatus (26) at a velocity of at least 45 meters per second and each of said multiple first openings (72) includes at least two crescent shaped slots (74).
- The apparatus of claim 1, wherein each of said multiple nozzles (44) is formed from stainless steel, and each of said multiple second openings (64) has a venturi formed therein.
- A process (10) of forming a non-woven cellulose web (14), comprising the steps of:a) forming an aqueous solution (20) of cellulose (16) and a solvent (18);b) directing said aqueous solution (20) through a first member (42) having multiple nozzles (44) arranged in rows (90), each of said nozzles (44) having an inside diameter through which said aqueous solution (20) passes, said first member (42) having multiple pins (66) arranged adjacent to said multiple nozzles (44), and said first member (42) having at least one passage (48) through which a pressurized gas (34) is routed, a second member (52) secured to said first member (42), said second member (52) having multiple corridors (54) formed therethrough which are connected to said at least one passage (48) formed in said first member (42), each of said multiple pins (66) passing through one of said multiple corridors (54), and multiple openings (58) formed through said second member (52) through which each of said multiple nozzles (44) can pass, and a third member (60) secured to said second member (52), said third member (60) having multiple first openings (62) formed therethrough, each of said first openings (62) sized to permit one of said multiple nozzles (44) to pass through, each of said first openings (62) being concentrically aligned about each of said multiple nozzles (44), each of said first openings (62) being connected to said pressurized gas corridors (54) formed in said second member (52) and each emitting pressurized gas (34) therethrough such that said pressurized gas (34) at least partially surrounds said aqueous solution (20) extruded from each of said multiple nozzles (44), and said third member (60) also having multiple second openings (64) formed therethrough which are connected to said pressurized gas corridors (54) formed in said second member (52), each of said multiple second openings (64) being larger than each of said multiple pins 66 and each of said multiple second openings (64) being positioned adjacent to one of said multiple nozzles (44), and each of said multiple second openings (64) having a diameter through which said pressurized gas (34) is emitted;c) extruding said aqueous solution (20) through each of said nozzles (44) to form multiple filaments (98);d) shrouding at least a portion of each of said filaments (98) in a pressurized gas (34) emitted through each of said adjacently aligned first and second openings (62, 64);e) attenuating said filaments (98) into a circular cross-sectional configuration having a diameter (d6) of less than about 15 µm (microns);f) contacting said filaments (98) with a liquid (104), said liquid (104) mixing with said solvent (18) to remove some of said solvent (18) whereby each of said filaments (98) is transformed into a continuous solid fiber (12); andg) collecting said continuous solid fibers (12) on a moving surface (106) to form a non-woven cellulose web (110).
- The process (10) of claim 5, further comprising heating said aqueous solution (20) to a temperature of from between 80°C to 140°C and heating said pressurized gas (34) to a temperature of at least 120°C, and extruding said aqueous solution (20) through each of said nozzles (44) at a throughput of greater than 0.1 grams/hole/minute.
- The process (10) of claim 5, further comprising emitting said pressurized gas (34) through each of said first openings (62) at a velocity of at least 45 meters per second and emitting said pressurized gas (34) through each of said second openings (64) at a velocity of at least 45 meters per second.
- The process (10) of claim 5, further comprising extruding said aqueous solution (20) downward from each of said nozzles (44) parallel to a longitudinal central axis (X) and contacting each of said filaments (98) with water (104) introduced at an angle (α) of from between 5 degrees to 175 degrees, said water (104) causing each of said filaments (98) to coagulate into a continuous solid fiber (12).
- The process (10) of claim 5, further comprising starting up said process by:a) heating said aqueous solution (20) to a predetermined temperature above 80° C;b) directing said heated aqueous solution (20) to said first member (42) and extruding said heated aqueous solution (20) through each of said nozzles (44) at a back pressure of at least 10 bar;c) routing said pressurized gas (34) through each of said first and second openings (62, 64) at a velocity of from between 1 meter per second to 10 meters per second;d) heating said pressurized gas (34) to a temperature of about 100° C; ande) gradually increasing said velocity of said heated pressurized gas (34) until said pressurized gas (34) reaches a velocity of at least about 45 meters per second.
- The process (10) of claim 5, further comprising shutting down said process by:a) turning off said heat used to heat said pressurized gas (34) ;b) gradually reducing said velocity of said pressurized gas (34) to 0 meters per second;c) stopping said aqueous solution (20) from flowing through each of said nozzles (44); andd) allowing said aqueous solution (20) to cool to room temperature.
- Use of an array (86) of nozzles (44) for extruding multiple cellulose fibers (12), said array (86) comprising:a) a first member (42) having multiple nozzles (44) arranged in rows (90), each of said multiple nozzles (44) having a longitudinal central axis and each including a tube (46) with a cross-section having a diameter through which an aqueous solution (20) comprised of cellulose (16) and a solvent (18) can be extruded into a filament (98), said first member (42) also having multiple pins (66) arranged adjacent to said multiple nozzles (44), and said first member (42) having at least one passage (40) through which a pressurized gas (34) is routed;b) a second member (52) secured to said first member (42), said second member (52) having multiple corridors (54) formed therethrough which are connected to said at least one passage (40) formed in said first member (42), each of said multiple pins (66) passing through one of said multiple corridors (54), and multiple openings (58) formed through said second member (52) through which each of said multiple nozzles (44) passes;c) a third member (60) secured to said second member (52), said third member (60) having multiple first openings (62) formed therethrough, each of said first openings (62) sized to permit one of said multiple nozzles (44) to pass through, each of said first openings (62) being concentrically aligned about each of said multiple nozzles (44), each of said first openings (62) being connected to said pressurized gas corridors (54) formed in said second member (52) and each emitting pressurized gas (34) therethrough such that said pressurized gas (34) at least partially surrounds said aqueous solution (20) extruded from each of said multiple nozzles (44), and said third member (60) also having multiple second openings (64) formed therethrough which are connected to said pressurized gas corridors (54) formed in said second member (52), each of said multiple second openings (64) being larger than each of said multiple pins (66) and each of said multiple second openings (64) being positioned adjacent to one of said multiple nozzles (44), and each of said multiple second openings (64) having a diameter through which said pressurized gas (34) is emitted, and wherein there are at least three of said second openings (64) each spaced outward from each of said first openings (62), each of said second openings (64) emitting a pressurized gas stream (102) essentially parallel to said longitudinal central axis of each of said multiple nozzles (44), and each of said pressurized gas streams (102) functioning to shroud one of said extruded filaments (98).
- The use of claim 11, wherein said pressurized gas (34) emitted from each of said first openings (62) attenuates and accelerates each of said filaments (98) extruded from each of said tubes (46) into a continuous fiber (12) having a diameter (d6) of less than 15 µm (microns).
- The use of claim 12, comprising using the apparatus (26) of claim 1 at a throughput of greater than 0.1 grams/hole/minute, wherein said extruded cellulose fibers (12) have a diameter (d6) of between 0.5 to 4 µm.
- The use of claim 11, wherein each of said first and second openings (62, 64) is aligned parallel to one another, and each of said second openings (64) is spaced from between 1 millimeter to 4 millimeters from said longitudinal central axis of said nozzle (44).
- The use of claim 14, wherein each of said second openings (64) is spaced from between 1 millimeter to 2 millimeters from said longitudinal central axis of one of said nozzles (44), each of said second openings (64) contains a venturi, and each of said tubes (46) is a hollow cylindrical tube (46) formed from stainless steel which extends downward beyond said first openings (62) by at least 1 millimeter.
- The use of claim 11, wherein said multiple nozzles (44) are arranged in rows (90), each of said nozzles (44) including a hollow cylindrical tube (46) with a cross-section and having a constant diameter positioned therein through which said aqueous solution (20) can be extruded, and each of said first openings (62) being concentrically aligned about each of said hollow cylindrical tubes (46) and having a cross-section with a constant diameter, said diameter of each of said first openings (62) being greater than said diameter of each of said hollow cylindrical tubes (46), and each of said first openings (62) emitting pressurized gas (34) therethrough which at least partially surrounds said extruded filament (98); said second openings (64) being arranged in said rows (90) with said multiple nozzles (44), at least two of said second openings (64) being positioned adjacent to one of said nozzles (44) in each of said rows (90), each of said second openings (64) emitting a pressurized gas (34); and at least one of said nozzles (44) in one row (90) being offset from one of said nozzles (44) in an adjacent row (90).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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PL09005315T PL2108719T3 (en) | 2008-04-11 | 2009-04-14 | An apparatus, process and an array of nozzles for extruding cellulose fibers |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/082,502 US8029259B2 (en) | 2008-04-11 | 2008-04-11 | Array of nozzles for extruding multiple cellulose fibers |
US12/082,504 US8303888B2 (en) | 2008-04-11 | 2008-04-11 | Process of forming a non-woven cellulose web and a web produced by said process |
US12/082,503 US8029260B2 (en) | 2008-04-11 | 2008-04-11 | Apparatus for extruding cellulose fibers |
Publications (2)
Publication Number | Publication Date |
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EP2108719A1 EP2108719A1 (en) | 2009-10-14 |
EP2108719B1 true EP2108719B1 (en) | 2012-06-20 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP09005315A Active EP2108719B1 (en) | 2008-04-11 | 2009-04-14 | An apparatus, process and an array of nozzles for extruding cellulose fibers |
Country Status (5)
Country | Link |
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EP (1) | EP2108719B1 (en) |
DK (1) | DK2108719T3 (en) |
ES (1) | ES2387729T3 (en) |
PL (1) | PL2108719T3 (en) |
PT (1) | PT2108719E (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103882535A (en) * | 2014-04-11 | 2014-06-25 | 天津工业大学 | Solution jetting spinning die head |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
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ES2625035B1 (en) * | 2015-12-18 | 2018-06-21 | Universidad De Extremadura | PRODUCTION OF VISCOELASTIC CAPILLARY JETS BY GASEOUS FOCUS |
CN111607829A (en) * | 2020-06-02 | 2020-09-01 | 刘剑鹏 | Spinneret plate of melt blowing machine, manufacturing method thereof and nozzle of melt blowing machine |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
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US4246221A (en) | 1979-03-02 | 1981-01-20 | Akzona Incorporated | Process for shaped cellulose article prepared from a solution containing cellulose dissolved in a tertiary amine N-oxide solvent |
US5330567A (en) | 1988-08-16 | 1994-07-19 | Lenzing Aktiengesellschaft | Process and arrangement for preparing a solution of cellulose |
AT396930B (en) | 1992-01-23 | 1993-12-27 | Chemiefaser Lenzing Ag | AMINOXIDE |
GB9219693D0 (en) | 1992-09-17 | 1992-10-28 | Courtaulds Plc | Forming solutions |
US5476616A (en) * | 1994-12-12 | 1995-12-19 | Schwarz; Eckhard C. A. | Apparatus and process for uniformly melt-blowing a fiberforming thermoplastic polymer in a spinnerette assembly of multiple rows of spinning orifices |
FR2735794B1 (en) * | 1995-06-26 | 1997-09-19 | Elysees Balzac Financiere | PROCESS FOR THE PREPARATION OF A MIXTURE OF CELLULOSIC FIBERS AND MICROFIBERS |
US6306334B1 (en) | 1996-08-23 | 2001-10-23 | The Weyerhaeuser Company | Process for melt blowing continuous lyocell fibers |
WO2005106085A1 (en) * | 2004-04-26 | 2005-11-10 | Biax Fiberfilm Corporation | Apparatus , product and process forming micro-fiber cellulosic nonwoven webs |
-
2009
- 2009-04-14 ES ES09005315T patent/ES2387729T3/en active Active
- 2009-04-14 PL PL09005315T patent/PL2108719T3/en unknown
- 2009-04-14 EP EP09005315A patent/EP2108719B1/en active Active
- 2009-04-14 PT PT09005315T patent/PT2108719E/en unknown
- 2009-04-14 DK DK09005315.8T patent/DK2108719T3/en active
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103882535A (en) * | 2014-04-11 | 2014-06-25 | 天津工业大学 | Solution jetting spinning die head |
CN103882535B (en) * | 2014-04-11 | 2017-05-17 | 天津工业大学 | Solution jetting spinning die head |
Also Published As
Publication number | Publication date |
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PL2108719T3 (en) | 2012-11-30 |
EP2108719A1 (en) | 2009-10-14 |
PT2108719E (en) | 2012-08-09 |
DK2108719T3 (en) | 2012-10-01 |
ES2387729T3 (en) | 2012-10-01 |
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