Contact With Liquid Coagulant Or Reactive Liquid Patents (Class 264/561)
  • Patent number: 8512627
    Abstract: The present invention provides a method for the production of a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) asymmetric hollow fiber membrane. The invention comprises preparing a dope solution of PVDF-HFP with an additive of lithium chloride or glycerol dissolved in a solvent such as N-methylpyrollidone (NMP). The dope solution is spun to form a PVDF-HFP asymmetric hollow fiber membrane.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: August 20, 2013
    Assignee: Nanyang Technological University
    Inventors: Rong Wang, David Tee Liang, Joo Hwa Tay
  • Patent number: 8454884
    Abstract: The present invention relates to a cellulose carbamate spinning solution, the cellulose carbamate being dissolved in at least one ionic liquid. Furthermore, the invention relates to a method for the production of blown films in which a solution of cellulose carbamate in an ionic liquid is extruded into a coagulation bath, and also to the films produced with the method and the use thereof.
    Type: Grant
    Filed: April 7, 2009
    Date of Patent: June 4, 2013
    Assignee: Fraunhofer-Gesellschaft zur Forderung der angewandten Forschung e.V.
    Inventors: Horst Ebeling, Hans-Peter Fink
  • Patent number: 8343414
    Abstract: A process and apparatus for multi-shot, liquid-resin-molding of continuous-fiber composite articles is disclosed. The process involves the step-wise fabrication of an article wherein continuity of the fibers is maintained between the multiple workpieces of the finished composite article.
    Type: Grant
    Filed: July 18, 2011
    Date of Patent: January 1, 2013
    Assignee: Lockheed Martin Corporation
    Inventors: Alan K. Miller, Stephen L. Bailey, Theodore Rosario, Jr.
  • Patent number: 8337744
    Abstract: A method and apparatus for maintaining constant compaction pressure in a vertically oriented resin transfer molding apparatus.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: December 25, 2012
    Assignee: Lockheed Martin Corporation
    Inventors: Alan K. Miller, Theodore Rosario, Michael M. Garcia
  • Patent number: 8303888
    Abstract: A process is disclosed of forming cellulose fibers. The process includes extruding an aqueous solution of cellulose and a solvent through a first member to form 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 filaments is shrouded in a pressurized gas emitted through each of the first openings. Each of the filaments is contacted with a liquid to remove some of the solvent and transform each of the filaments into a continuous solid fiber. The continuous solid fibers are then collected on a moving surface to form a non-woven cellulose web.
    Type: Grant
    Filed: April 11, 2008
    Date of Patent: November 6, 2012
    Assignee: Reifenhauser GmbH & Co. KG
    Inventors: Douglas B. Brown, Jeffrey D. Stark, Carmen A. Granato, Sr., Duane K. Zacharias
  • Patent number: 8051991
    Abstract: A process for manufacturing of an asymmetric hollow fiber membrane, comprising the steps of extruding a polymer solution through the outer ring slit of a hollow fiber spinning nozzle, simultaneously extruding a center fluid through the inner bore of the hollow fiber spinning nozzle, into a precipitation bath, whereby the polymer solution contains 10 to 26 wt-% of polysulfone (PSU), polyethersulfone (PES) or polyarylethersulfone (PAES), 8 to 15 wt-% polyvinylpyrrolidone (PVP), 55 to 75 wt-% N-alkyl-2-pyrrolidone (NAP) and 3 to 9 wt-% water the centre fluid contains 70 to 90 wt-% N-alkyl-2-pyrrolidone (NAP) and 10 to 30 wt-% water, and the precipitation bath contains 0 to 20 wt-% N-alkyl-2-pyrrolidone (NAP) and 80 to 100 wt-% water.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: November 8, 2011
    Assignee: Gambro Lundia AB
    Inventors: Bernd Krause, Markus Hornung, Herman Goehl
  • Patent number: 8025834
    Abstract: A process and apparatus for multi-shot, liquid-resin-molding of continuous-fiber composite articles is disclosed. The process involves the step-wise fabrication of an article wherein continuity of the fibers is maintained between the multiple workpieces of the finished composite article.
    Type: Grant
    Filed: June 15, 2009
    Date of Patent: September 27, 2011
    Assignee: Lockheed Martin Corporation
    Inventors: Alan K. Miller, Stephen L. Bailey, Theodore Rosario, Jr.
  • Patent number: 7811507
    Abstract: A hydrophilic semipermeable hollow-fibre membrane for blood treatment, with an integrally asymmetric structure based on a synthetic polymer. The hollow-fiber membrane possess on its inner surface a separating layer and an adjoining open-pored supporting layer, and has an ultrafiltration rate in albumin solution of 5 to ?25 ml/(h·m2·mmHg). The hollow fiber membrane is free from pore-stabilizing additives and has a maximum sieving coefficient for albumin of 0.005 and a sieving coefficient of cytochrome c that satisfies the equation SCcc?5·10?5·UFRAlb3?0.004·UFRAlb2+0.1081·UFRAlb?0.25.
    Type: Grant
    Filed: February 15, 2005
    Date of Patent: October 12, 2010
    Assignee: Membrana GmbH
    Inventors: Friedbert Wechs, Arne Gehlen, Bodo Von Harten, Richard Kruger, Oliver Schuster
  • Patent number: 7767756
    Abstract: The application describes materials derived from keratin proteins in combination with polymers, either as intimate mixtures with water soluble polymers, or as chemically bound copolymers. The keratin protein is a specific keratin protein fraction, and is preferably intact, s-sulfonated and from the intermediate filament protein family. The application also describes the process for production of these materials.
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: August 3, 2010
    Assignee: Keraplast Technologies, Ltd.
    Inventors: Robert James Kelly, Mohammad Azam Ali, Alisa Dawn Roddick-Lanzilotta, Gillian Worth, Mohammad Mahbubul Hassan, John Robert McLaughlin, Alan John McKinnon
  • Publication number: 20100164148
    Abstract: The present invention relates to an acid-doped polymer membrane based on polyazoles. The acid-doped polymer membrane can be used in a variety of applications because of its excellent mechanical properties and is useful as polymer electrolyte membrane (PEM) in PEM fuel cells. A doped polymer membrane based on polyazoles is obtained by a process comprising the steps of: A) casting a film using a solution of polymers based on polyazoles in a polar, aprotic organic solvent; B) drying the film formed in step A) until it is self-supporting; C) treating the film obtained in step B) with a treatment liquid at a temperature in the range from room temperature to the boiling point of the treatment liquid; D) drying and/or dabbing the film treated according to step C) to remove the treatment liquid from step C); and E) doping the film treated according to step D) with a doping agent.
    Type: Application
    Filed: March 9, 2010
    Publication date: July 1, 2010
    Inventors: Oemer Uensal, Joachim Kiefer, Jochen Baurmeister, Jürgen Pawlik, Werner Kraus, Frauke Jordt
  • Publication number: 20090258562
    Abstract: A process is 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.
    Type: Application
    Filed: April 11, 2008
    Publication date: October 15, 2009
    Applicant: Biax Fiberfilm
    Inventors: Douglas B. Brown, Jeffrey D. Stark, Carmen A. Granato, SR., Duane K. Zacharias
  • Patent number: 7504034
    Abstract: A method of producing a hollow fiber membrane includes discharging a polyvinylidene fluoride solution comprising a polyvinylidene fluoride resin and a poor solvent at a temperature above a phase separation temperature into a cooling bath at a temperature below the phase separation temperature to coagulate the polyvinylidene fluoride resin. The hollow fiber membrane comprises a polyvinylidene fluoride resin having spherical structures that have an average diameter in the range of 0.3 to 30 ?m.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: March 17, 2009
    Assignee: Toray Industries, Inc.
    Inventors: Shin-Ichi Minegishi, Masahiro Henmi, Toshiyuki Ishizaki, Koichi Dan
  • Patent number: 7368526
    Abstract: Functionalized porous poly(aryl ether ketone) articles are prepared by reacting ketone groups in the backbone of poly(aryl ether ketone) polymer with a primary amine reagent. Preferred functional primary amines are primary aliphatic amines or substituted hydrazines containing one or more target functional groups including polar groups, such as hydroxyl groups, ˜OH, amino groups, ˜NH2, ˜NHR, ˜NRR?, and ethylene oxide groups, ˜OCH2CH2—, negatively or positively charged ionic groups, such as ˜SO3?, ˜COO?, and ˜NH4+ groups, hydrophobic groups such as siloxane or perfluorcarbone groups, and non-polar groups, such as linear or branched hydrocarbon groups. The functionalized porous poly(aryl ether ketone) article can be prepared by reacting primary amine with a pre-formed, shaped porous poly(aryl ether ketone) article or by functionalizing the surface of a non-porous precursor article that is subsequently converted into a porous article.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: May 6, 2008
    Assignee: Porogen Corporation
    Inventors: Youxin Yuan, Yong Ding
  • Patent number: 7303609
    Abstract: A process for the manufacture of a polyimide hollow fibre comprising: (i) providing a dope solution comprising one or more polyimides dissolved in a solvent comprising 60-100 wt % N-methylpyrollidone and 0-40 wt % ethanol, (ii) providing a bore fluid, (iii) generating a tube of the dope solution filled with the bore fluid, (iv) bringing the product of step (iii) into contact with a coagulation solvent to form a hollow fiber.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: December 4, 2007
    Assignee: British Gas Asia Pacific Pte Limited
    Inventors: Tai-Shung Chung, Rong Wang, Ji Zhong Ren, Chun Cao, Ye Liu, Dong-Fei Li
  • Patent number: 7229580
    Abstract: The preparation and use of novel porous poly(aryl ether) articles is disclosed. The porous articles are prepared from blends of poly(aryl ether) polymers with polyimides by selectively decomposing the polyimide phase. The preferred reagents used to decompose the polyimide phase include monoethanolamine and tetramethylammonium hydroxide. The porous articles can be configured as a single layer or as a multilayer article. The porous articles of the present invention are unique that at least one of the layers exhibits a narrow pore size distribution. The articles of the present invention can be used as a porous media for a broad range of applications, including porous membranes for fluid separations, such as microfiltration, ultrafiltration, and gas separation, as a battery separators, and as a sorption media.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: June 12, 2007
    Assignee: PoroGen Corporation
    Inventor: Youxin Yuan
  • Patent number: 7176273
    Abstract: Functionalized porous poly(aryl ether ketone) articles are prepared by reacting ketone groups in the backbone of poly(aryl ether ketone) polymer with a primary amine reagent. Preferred functional primary amines are primary aliphatic amines or substituted hydrazines containing one or more target functional groups including polar groups, such as hydroxyl groups, ˜OH, amino groups, ˜NH2, ˜NHR, ˜NRR?, and ethylene oxide groups, ˜OCH2CH2—, negatively or positively charged ionic groups, such as ˜SO3?, ˜COO?, and ˜NH4+ groups, hydrophobic groups such as siloxane or perfluorcarbone groups, and non-polar groups, such as linear or branched hydrocarbon groups. The functionalized porous poly(aryl ether ketone) article can be prepared by reacting primary amine with a pre-formed, shaped porous poly(aryl ether ketone) article or by functionalizing the surface of a non-porous precursor article that is subsequently converted into a porous article.
    Type: Grant
    Filed: November 3, 2004
    Date of Patent: February 13, 2007
    Assignee: PoroGen LLC
    Inventors: Youxin Yuan, Yong Ding
  • Patent number: 6887408
    Abstract: Porous poly(aryl ether ketone) (PAEK) articles are prepared from PAEK/polyimide blends by selective chemical decomposition and subsequent removal of the polyimide phase. Porous PAEK articles exhibit highly interconnected pore structure and a narrow pore size distribution. The porous PAEK articles of the present invention can be utilized as a porous media for a broad range of applications, including membranes for fluid separations, such as microfiltration, ultrafiltration, nanofiltration, and as a sorption media.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: May 3, 2005
    Assignee: PoroGen LLC
    Inventor: Youxin Yuan
  • Patent number: 6881361
    Abstract: The invention relates to a method for producing shaped bodies, especially threads or foils, from at least one polymer of the groups consisting of polysaccharide, polysaccharide derivative or polyvinyl alcohol by forming a solution of the polymer that contains an additive in a solvent containing amine-N-oxide, extruding the solution and precipitating the extrudate by contacting with a coagulant. The invention is characterized in that at least two polymeric solutions are formed. At least one of the two polymeric solutions contains one or more finely distributed additives and the at least two polymeric solutions are simultaneously extruded forming a combined extrudate.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: April 19, 2005
    Assignee: Ostthuringische Materialprufgesellschaft fur Textil und Kunststoffe mbH
    Inventors: Thomas Schulze, Eberhard Taeger, Dieter Vorbach
  • Patent number: 6875397
    Abstract: An apparatus for forming a fiber from a biocompatible biopolymer includes a fiber-formation tube that defines a bore extending generally vertically from an upper end to a lower end. Coagulation fluid enters the tube through a fluid inlet coupled to its upper end and establishes a laminar flow of coagulation fluid within the tube. A spinneret introduces a stream of liquid biopolymer into the laminar flow of coagulation fluid so that the stream is surrounded and swept downstream by the coagulation fluid as it coagulates into a biopolymer fiber. The laminar flow of coagulation fluid surrounding the biopolymer stream maintains the shape of the stream so that the resulting fiber is homogeneous in both geometry and structure. The laminar flow of coagulation fluid also prevents the resulting fiber from contacting the inner wall of the fiber-formation tube.
    Type: Grant
    Filed: October 19, 2001
    Date of Patent: April 5, 2005
    Assignee: TEI Biosciences, Inc.
    Inventor: Timothy W. Fofonoff
  • Patent number: 6821591
    Abstract: The present invention provides a seamless tubular film on a cellulose base, being produced by extruding an aqueous cellulose N-methyl-morpholine-N-oxide spinning solution. The maximum degree of roughness Rmax is from greater than 0.1 &mgr;m to 0.5 &mgr;m and an average degree of roughness Rm is from 0.005 to 0.014 &mgr;m. On the surface of the tubular film is formed in contact with an electrolyte an electrokinetic potential, the size of which depends on the pH value of the electrolyte.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: November 23, 2004
    Assignee: Kalle GmbH & Co. KG
    Inventors: Herbert Gord, Klaus-Dieter Hammer, Rainer Neeff, Klaus Berghof, Markus Eilers, Reinhard Maron
  • Patent number: 6685856
    Abstract: The use of low specific gravity wood from thinning operations, for example, will produce a lower brownstock viscosity for a given kappa number target. A differential of 200-cP falling ball pulp viscosity has been detected from Kraft cooks of low and high specific gravity wood. Using low specific gravity wood can reduce the bleach stage temperature and the chemical dose needed in the bleach plant to produce lyocell pulp specifications. Low specific gravity wood also increases the ability to reduce pulp viscosity to very low levels without increasing the copper number of the pulp or the concentration of carbonyl in the pulp above acceptable levels.
    Type: Grant
    Filed: January 2, 2003
    Date of Patent: February 3, 2004
    Assignee: Weyerhaeuser Company
    Inventors: James E. Sealey, II, W. Harvey Persinger, Jr., Kent Robarge, Mengkui Luo
  • Publication number: 20030160348
    Abstract: The invention relates to a method for producing extruded, cellulosic continuous shaped bodies from an extrusion solution containing cellulose, water and tertiary amino-oxide. In order to improve the textile properties of the extruded continuous shaped bodies with regard to the prior art, the invention provides that the continuous shaped body (5) is conveyed, with essentially no tensile stress, on a conveying device (11) between an extrusion nozzle opening and a take-off unit (24). To this end, the speed of conveyance of the interconnected conveying device (11) is preferably less than the extrusion rate and less than the take-off rate of the take-off unit (24). By employing these measures, the textile properties such as loop strength and tendency to fibrillate can be considerably improved.
    Type: Application
    Filed: April 22, 2003
    Publication date: August 28, 2003
    Inventors: Stefan Zikeli, Friedrich Ecker
  • Publication number: 20030098527
    Abstract: An apparatus for forming a fiber from a biocompatible biopolymer includes a fiber-formation tube that defines a bore extending generally vertically from an upper end to a lower end. Coagulation fluid enters the tube through a fluid inlet coupled to its upper end and establishes a laminar flow of coagulation fluid within the tube. A spinneret introduces a stream of liquid biopolymer into the laminar flow of coagulation fluid so that the stream is surrounded and swept downstream by the coagulation fluid as it coagulates into a biopolymer fiber. The laminar flow of coagulation fluid surrounding the biopolymer stream maintains the shape of the stream so that the resulting fiber is homogeneous in both geometry and structure. The laminar flow of coagulation fluid also prevents the resulting fiber from contacting the inner wall of the fiber-formation tube.
    Type: Application
    Filed: October 19, 2001
    Publication date: May 29, 2003
    Applicant: TEI Biosciences, Inc.
    Inventor: Timothy W. Fofonoff
  • Publication number: 20030094409
    Abstract: A method of producing a hollow fiber membrane includes discharging a polyvinylidene fluoride solution comprising a polyvinylidene fluoride resin and a poor solvent at a temperature above a phase separation temperature into a cooling bath at a temperature below the phase separation temperature to coagulate the polyvinylidene fluoride resin. The hollow fiber membrane comprises a polyvinylidene fluoride resin having spherical structures that have an average diameter in the range of 0.3 to 30 &mgr;m.
    Type: Application
    Filed: September 27, 2002
    Publication date: May 22, 2003
    Applicant: Toray Industries, Inc.
    Inventors: Shin-ichi Minegishi, Masahiro Henmi, Toshiyuki Ishizaki, Koichi Dan
  • Patent number: 6521025
    Abstract: A hollow fibre membrane has an active layer (2) in which elongate polymer molecules (3) are longitudinally aligned essentially parallel to the extrusion direction to thereby define a plurality of spaced free volume cavities (4) which are particularly numerous and are essentially regularly spaced to provide enhanced selectivity when used in gas separation. The hollow fibre membrane is manufactured using a dry/wet phase separation process by spinning a dope composition which is extruded through a spinneret (12) having an annulus or annular orifice (16) together with a bore-forming fluid or coagulant. The dope composition has a power law index of less than 1 (unity) and the bore coagulant has a water activity of less than 1 (unity).
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: February 18, 2003
    Assignee: University of Strathclyde
    Inventors: Simon James Shilton, Ahmad Fauzi Ismail
  • Patent number: 6521169
    Abstract: Process for the production of cellulose shaped bodies through the precipitation of a cellulose solution containing cellulose dissolved in an amine oxide/water system in a precipitation bath, wherein the solution contains additional cellulose fibers.
    Type: Grant
    Filed: August 6, 1999
    Date of Patent: February 18, 2003
    Assignee: Fraunhofer-Gesellschaft zur Forderung der Angewandten Forschung e.V.
    Inventors: Peter Weigel, Hans-Peter Fink, Konrad Frigge
  • Publication number: 20030025252
    Abstract: A process for making lyocell fibers comprising the steps of pulping raw material in a digester to provide an alkaline pulp, wherein the raw material comprises sawdust in an amount greater than 0% up to 100%; contacting the alkaline pulp comprising cellulose and at least about 7% hemicellulose under alkaline conditions with an amount of an oxidant sufficient to reduce the average degree of polymerization of the cellulose to the range of from about 200 to about 1100 without substantially reducing the hemicellulose content or substantially increasing the copper number of the pulp; and forming fibers from the pulp.
    Type: Application
    Filed: April 23, 2002
    Publication date: February 6, 2003
    Applicant: Weyerhaeuser Company
    Inventors: James E. Sealey, W. Harvey Persinger, Mengkui Luo, Brian Wester
  • Publication number: 20030025251
    Abstract: A process for making a composition for conversion to lyocell fiber where the process comprises pulping a raw material in a digester to provide an alkaline pulp, wherein the raw material comprises sawdust in an amount greater than 0% up to 100%; and contacting the alkaline pulp comprising cellulose and at least about 7% hemicellulose under alkaline conditions with an amount of an oxidant sufficient to reduce the average degree of polymerization of the cellulose to within the range of from about 200 to about 1100, without substantially reducing the hemicellulose content of the pulp or substantially increasing the copper number.
    Type: Application
    Filed: April 23, 2002
    Publication date: February 6, 2003
    Applicant: Weyerhaeuser Company
    Inventors: James E. Sealey, W. Harvey Persinger, Mengkui Luo, Brian Wester
  • Patent number: 6436319
    Abstract: A method for preparing a hollow fiber-type separation membrane from high density polyethylene is provided, which includes the steps of: melt-spinning a mixture of a high density polyethylene and a diluting agent to produce a phase-separated undrawn hollow fiber; detecting a tensile strength of the undrawn fiber during an alternative and repetitive winding and unwinding procedure between two bobbins, said undrawn fiber being drawn during the alternative and repetitive winding and unwinding procedure; reducing a rotation speed of one of the two bobbins when the detected tensile strength is larger than a predetermined value; and increasing a rotation speed of one of the two bobbins when the detected tensile strength is smaller than the predetermined value to yield the hollow fiber-type separation membrane.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: August 20, 2002
    Assignee: Agency for Technology and Standards
    Inventors: Hyang Sun, Yong Sang Yi, Kyu Bong Rhee
  • Publication number: 20020056682
    Abstract: A method and apparatus for purifying an aqueous suspension comprising feeding an aqueous suspension containing fine particles comprising an inorganic component from the outer surface of a wavy hollow fiber membrane having an outer diameter of from 0.5 to 3.1 mm to filter, followed by physical wash of the hollow fiber membrane. The purifying method can reduce the damage of the membrane outer surface during the physical wash step, prevent open pores on the surface from covering and achieve stable filtration. The hollow fiber membrane bundle can be produced by having a pulsation flow contacted with the hollow fiber material being extruded from the double spinning nozzle under specific conditions and cooling and solidifying or coagulating it while shaking.
    Type: Application
    Filed: September 14, 2001
    Publication date: May 16, 2002
    Applicant: Asahi Kasei Kabushiki Kaisha
    Inventors: Tohru Taniguchi, Nobuhiko Suga, Takehiko Otoyo
  • Publication number: 20020022100
    Abstract: The present invention that also possesses provides a method for producing a seamless tubular film based on cellulose comprising extruding an aqueous cellulose-N-methyl-morpholine-N-oxide (NMMO) spinning solution through an annular die in a spinning bath, wherein the spinning solution forms the tubular film. The film is laterally drawn in an air gap between the annular die and the spinning bath by stabilizing air pressure in the tubular film. The level of hydrostatic pressure from an inner spinning solution formed inside the tubular film extends above the spinning bath, the inner spinning solution comprising an aqueous NMMO solution that supports and intensifies said lateral drawing. The tubular film that has been expanded by the lateral drawing process is passes by a turning point in the spinning bath, and directed out of the spinning bath.
    Type: Application
    Filed: July 20, 2001
    Publication date: February 21, 2002
    Inventors: Herbert Gord, Klaus-Dieter Hammer, Rainer Neeff, Klaus Berghof, Markus Eilers, Reinhard Maron
  • Patent number: 6306334
    Abstract: The present invention is directed to a method of preparing continuous lyocell fibers by melt blowing techniques, a pulp useful for making lyocell fibers and to the fibers produced by the method. In particular, the method enables high throughputs of fibers of cotton-like deniers. The fibers are readily cut into staple lengths and can be spun into yarns with excellent knitting and weaving characteristics which dye exceptionally well.
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: October 23, 2001
    Assignee: The Weyerhaeuser Company
    Inventors: Mengkui Luo, Vincent A. Roscelli, Senén Camarena, Amar N. Neogi, Michael J. Yancey, Paul G. Gaddis
  • Patent number: 6264874
    Abstract: A method and apparatus for controlling the diameter of a clear extruded molten tube wherein the extruded tube contains a volume of a clear liquid and the level of the liquid is indicative of the tube diameter so the level rises as the tube diameter decreases. A light beam passing through the tube is refracted from a straight line path when the liquid level rises above the level of the beam. The refracting of the beam in turn triggers the introduction of air into the extruded tube to increase the diameter of the extruded, molten tube.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: July 24, 2001
    Assignee: Viskase Corporation
    Inventor: Niel Edwin Nielsen
  • Patent number: 6214283
    Abstract: Method for treating an extruded plastic section having a hollow space and installation suitable for carrying out such a treatment. The installation includes an extruder which has a core for forming the hollow space in the section and, at a distance downstream from the extruder in the extrusion direction of the section, a closing means having a rigid circumferential wall. The installation also has a first conduit connected to a supply orifice which is provided in the circumferential wall of the closing means, a fluid feeder connected to the first conduit and a second conduit connected to a discharge orifice. The discharge orifice is upstream of the supply orifice to provide a fluid film flowing opposite to the extrusion direction between the circumferential wall of the closing means and the extruded section.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: April 10, 2001
    Assignee: Wavin B.V.
    Inventors: Jan Visscher, Jan Hendrik Prenger, Johan Schuurman
  • Patent number: 6143219
    Abstract: The present invention discloses a generic method for producing void and gas occlusion free materials, as well as apparatuses for batch and continuous production of same. This generic method can be utilized in the production of a wide variety of polymeric compounds and composites and specifically encompasses the two ends of the polymeric composite spectrum, that is, polymer concretes on the one hand, and fiber-reinforced polymer composites on the other. The composite materials of the present invention are characterized by visual count as being void and gas occlusion free to the level of 1 micron at 1250.times. magnification. Concomitantly, the invention produces useful polymer concrete materials which exhibit substantially improved integrity for easy machining at high speeds, and high dielectric and mechanical strength, as compared with composite materials produced by conventional methods.
    Type: Grant
    Filed: November 20, 1998
    Date of Patent: November 7, 2000
    Assignee: Mardela International Inc. S.A.
    Inventors: Victor H. Vidaurre, Wilfredo G. Bendek, Jorge L. Dufeu
  • Patent number: 6113842
    Abstract: The invention is directed to a method of manufacturing oriented cellulose films by spinning non-derivated cellulose dissolved in amino oxides into a precipitating bath. The cellulose solution is extruded downward through a film-blowing nozzle and an external air gap into the precipitating bath. The spun cellulose film can be inflated after exiting the film-blowing nozzle.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: September 5, 2000
    Assignee: Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E. V.
    Inventors: Peter Weigel, Hans-Peters Fink, Konrad Frigge, Wolfgang Schwarz
  • Patent number: 6103117
    Abstract: Respective hollow fiber membranes suitable for use in removing undesired contaminants from blood, in particular in an artificial kidney, have:(1) per membrane area of 1.8 m.sup.2, in vitro clearances for urea and phosphorus respectively of .gtoreq.195, and .gtoreq.180, ml/min, a .beta..sub.2 -microglobulin clearance .gtoreq.44 ml/min and an albumin permeability .ltoreq.0.5%;(2) an albumin permeability .ltoreq.1.5% and an overall mass transfer coefficient Ko .gtoreq.0.0012 cm/min; and(3) a vitamin B.sub.12 dialyzance of .gtoreq.135 ml/min and an albumin permeability .ltoreq.3%. The membranes can be prepared by spinning hollow fibers from a spinning solution comprising a polysulfone, a hydrophilic polymer, a solvent and water, the spinning solution having a viscosity x at 30.degree. C. of 25-130 poise and a quantity y % of water given by:-0.01x+1.45.ltoreq.y.ltoreq.-0.01x+2.
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: August 15, 2000
    Assignee: Toray Industries, Inc.
    Inventors: Masaaki Shimagaki, Fumiaki Fukui, Takeshi Sonoda, Koji Sugita
  • Patent number: 6096258
    Abstract: A method and apparatus is disclosed for forming a cellulose film suitable for direct food contact by precipitation from a solution of cellulose water and a tertiary amine oxide cellulose solvent. After precipitation of a cellulose gel from the solution, the gel is washed at ever increasing temperatures and then dried to provide a cellulose film having a solvent level to not more than 40 ppm. Portions of the wash water is collected and treated to recover the solvent for reuse.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: August 1, 2000
    Assignee: Viskase Corporation
    Inventors: Paul Edmund DuCharme, Jr., Edward Makoto Kajiwara, Norman Abbye Portnoy
  • Patent number: 6033618
    Abstract: A seamless cellulose-based tubular film is produced by extrusion of an aqueous cellulose-N-methylmorpholine N-oxide solution.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: March 7, 2000
    Assignee: Kalle Nalo GmbH & Co. KG
    Inventors: Herbert Gord, Klaus-Dieter Hammer, Helmut Sattler
  • Patent number: 6017474
    Abstract: Formulation polymer dopes and development of processes for preparing asymmetric polyethersulfone hollow fiber membranes for gas separation are provided. Polyethersulfone hollow fiber membranes which exhibit improved gas permeability and selectivity have been produced from a formulated polymer dope containing N-methyl-2-pyrrolidone (NMP) and suitable nonsolvent-additives (NSA). The nonsolvent-additives are water and the mixture of ethanol and water. The dopes were tailored to be close to the point of phase separation, and have moderate polymer concentration with moderate viscosity. The hollow fibers were spun by the dry-wet phase inversion processes using water as both the internal and external coagulant. The dried hollow fibers are then coated with silicone rubber, a highly permeable material and the coated hollow fiber membranes exhibit excellent permeability and selectivity compared to those of the state-of-the-art polyethersulfone membranes.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: January 25, 2000
    Assignee: National University of Singapore
    Inventors: Wah Koon Teo, Kang Li, Dongliang Wang
  • Patent number: 6015516
    Abstract: A process for forming ultrathin dense-layer asymmetric hollow fiber membranes with a dense layer of less than 500 .ANG. from a binary solution system comprising a polymer and a solvent. In this process, the spinning polymeric solution has a high viscosity and exhibits chain entanglement at the spinning temperature. The solubility parameter difference between the bore fluid and the spinning dope is less than 2.5 (cal/cm.sup.3).sup.0.5 and the volume ratio of bore-fluid flow rate to the dope flow rate is between 0.45 to 0.75. The dope is wet-spun into hollow fibers using water as external coagulant. The ultrathin dense-layer asymmetric hollow fiber membranes are suitable for air and other gas separations.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: January 18, 2000
    Assignee: National University of Singapore
    Inventors: Tai-Shung Chung, Xudong Hu, Soo Khean Teoh
  • Patent number: 6001288
    Abstract: A process for producing a hollow fiber membrane, a hollow fiber membrane, and a dialyzer of hollow fiber membrane type is provided. The hollow fiber membrane is highly biocompatible, and the production process is quite simple and inexpensive. In the process of the invention, the hollow fiber membrane is produced in a system wherein a polymer-containing spinning solution is extruded from a tube-in-tube type orifice of a spinner in a coagulation solution to form the hollow fiber membrane. The polymer-containing spinning solution is extruded from the outer tube of the orifice to form a cylindrical filament having an inner bore and a core solution is ejected from the inner tube of the orifice into the inner bore of the filament for coagulation of the filament. The filament is directly extruded into the coagulation solution or extruded into air and then drawn to the coagulation solution.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: December 14, 1999
    Assignee: Terumo Kabushiki Kaisha
    Inventors: Makoto Saruhashi, Masatomi Sasaki
  • Patent number: 5910274
    Abstract: Improved anisotropic fluid separation membranes are prepared from blends of polymers with surface energy differences. The membranes are formulated by processes wherein low surface energy polymer with desirable fluid separation and permeation characteristics is preferentially concentrated in the surface discriminating layer of the membrane.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: June 8, 1999
    Assignee: Praxair Technology, Inc.
    Inventors: James Timothy Macheras, Benjamin Bikson, Joyce Katz Nelson
  • Patent number: 5856426
    Abstract: A para-oriented polyamide porous film comprising a fibril having a diameter of not more than 1.mu., with fibrils planarly arranged as a network or nonwoven fabric and laminated in a layer, the thermal linear expansion coefficient at 200.degree.-300.degree. C. within .+-.50.times.10.sup.-6 /.degree.C. and 30-95% vacant spaces. Also, a battery separator using the porous film. Also, a production process of: (a) forming a film-like material from a solution containing 1-10% of a para-oriented aromatic polyamide having an inherent viscosity of 1.0-2.8 dl/g and 1-10% of a chloride of an alkali metal or an alkali earth metal in a polar amide or polar urea solvent; (b) maintaining the film-like material at not less than 20.degree. C. and not more than -5.degree. C.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: January 5, 1999
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tsutomu Takahashi, Tatsuo Tateno, Yoshifumi Tsujimoto
  • Patent number: 5853884
    Abstract: A method for forming a hollow fiber bundle unit for insertion into an assisted breathing device comprising spinning a hollow fiber or hollow fibers, collecting multiple fibers into a bundle, filling the walls of the hollow fibers within the hollow fiber bundle with an humectant, coating the hollow fibers containing the humectant with a solution of an adhesive material, forming and drying the hollow fiber bundle coated with the solution, and preparing the hollow fiber bundle coated with the solution for insertion into the assisted breathing device.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: December 29, 1998
    Assignee: Whatman, Inc.
    Inventors: Randall W. Nichols, James C. Davis
  • Patent number: 5820934
    Abstract: The present invention relates to a method for the production of a fiber-reinforced cellulose tube by continuous coating of a fibrous non-woven fabric with an alkaline viscose solution which is neutralized by means of an acid-containing precipitating liquid and is converted into regenerated cellulose, wherein on the path between viscose coating and immersion in the precipitating bath, aqueous, acid-containing precipitating agents are caused to act upon the fresh viscose tube within the tube for the purpose of stiffening and regeneration to form regenerated cellulose, the process being begun with the application of the precipitating liquid directly after conclusion of the embedding of fiber in viscose and the precipitating liquid being guided together with the tube with the aid of optionally fixed internal devices which are designed in such a way that they support the tube that has had precipitating bath applied to it and in the process maintain it in rounded shape, that the length of the inner preliminary prec
    Type: Grant
    Filed: May 9, 1997
    Date of Patent: October 13, 1998
    Assignee: Wolff Walsrode AG
    Inventor: Klaus Basfeld
  • Patent number: 5795523
    Abstract: The present invention relates to an improved method for producing tubular sausage casings of regenerated cellulose wherein viscose is extruded through an annular extrusion die submerged in an aquarium to form a tubular product and coagulation and regeneration of the tubular product is initiated in said aquarium, continued by spray application of an intermediate regenerating solution in an intermediate regeneration zone after the tubular product has exited the aquarium, and completed in one or more coagulation/regeneration baths which includes the step of heating the tubular product to a temperature above the boiling point of carbon bisulphide in the intermediate reaction zone.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: August 18, 1998
    Assignee: Alfacel s.a.
    Inventor: Alexander Rozenberg
  • Patent number: 5766540
    Abstract: The tubular extrusion of a thermoplastic nonderivatized cellulose solution about a mandrel and through a long air gap in excess of 304 mm is facilitated by use of a mandrel which is extensible from the extrusion die. On extrusion start-up, the mandrel extends a short length from the die. For steady-state operation, the mandrel is extended its full length from the die. Also disclosed is a mandrel structure to facilitate the introduction of a nonsolvent liquid into the interior of the extruded tube at a high location on start-up of extrusion and at a lower location during steady-state operation.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: June 16, 1998
    Assignee: Viskase Corporation
    Inventors: Edward Makoto Kajiwara, Joseph Robert Walta, Ronald Joseph Jerantowski
  • Patent number: 5759478
    Abstract: The tubular extrusion of a thermoplastic nonderivatized cellulose solution about a mandrel and through a long air gap in excess of 304 mm is facilitated by use of a mandrel which is extensible from the extrusion die. On extrusion start-up, the mandrel extends a short length from the die. For steady-state operation, the mandrel is extended its full length from the die. Also disclosed is a mandrel structure to facilitate the introduction of a nonsolvent liquid into the interior of the extruded tube at a high location on start-up of extrusion and at a lower location during steady-state operation. The mandrel also includes a sizing portion having circumferential grooves which gather gas bubbles that may evolve at the interface between the extruded tube and the sizing portion. Vertical channels in the sizing portion connect these grooves and provide the passage of gas bubbles into a volume below the mandrel.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: June 2, 1998
    Assignee: Viskase Corporation
    Inventors: Edward Makoto Kajiwara, Brant Anton Loichinger
  • Patent number: 5702515
    Abstract: The use together of (1) an aromatic compound containing a benzene ring bearing at least two substituents selected from the group consisting of hydroxy groups, primary amino groups and secondary amino groups and (2) a sulphur-containing compound containing an --SH group or an anion or precursor thereof, not being a carbocyclic arenethiol, is effective in stabilising solutions of polysaccharides such as cellulose in tertiary amine N-oxides against thermal degradation. Such solutions are useful for the manufacture of extruded articles such as fibers and films.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: December 30, 1997
    Assignee: Courtaulds Fibres (Holdings) Limited
    Inventor: Peter George Urben