Cellulose Derivatives Patents (Class 264/187)
  • Patent number: 6190596
    Abstract: A process for producing cellulosic shaped objects includes extruding and coagulating a solution of chemical wood pulp in a tertiary amine oxide, and possibly a liquid that does not dissolve wood pulp and is miscible with the tertiary amine oxide, the solution capable of being shaped into objects, the process of producing the shapeable solution employing a first wood pulp with a higher degree of polymerization and a second wood pulp with a lower degree of polymerization, and whereby initially a solution of the first wood pulp with a higher degree of polymerization in the tertiary amine oxide and possibly non-dissolving liquid, and a composition containing the second wood pulp with a lower degree of polymerization, tertiary amine oxide, and possibly non-dissolving liquid, are prepared separately, and the solution and composition are subsequently at least mixed to obtain the shapeable solution.
    Type: Grant
    Filed: April 9, 1999
    Date of Patent: February 20, 2001
    Assignee: Akzo Nobel N.V.
    Inventors: Derek Budgell, Ulrich Wachsmann, Wilhelm Kramer
  • Patent number: 6177035
    Abstract: The invention relates to a process for the manufacture of cellulosic flat films and of cellulosic membranes in the form of flat membranes whereby a solution of cellulose in an aqueous tertiary amine oxide is extruded by means of an extrusion nozzle, which has an extrusion gap, whereby the solution is shaped in the form of a film and the solution is led into a precipitation bath via an air gap and is characterized in that an extrusion nozzle is used which has an extrusion gap with a minimum length of 40 cm.
    Type: Grant
    Filed: June 14, 1999
    Date of Patent: January 23, 2001
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Christian Schlossnikl, Siegfried Ambrosch, Heinrich Firgo, Peter Gspaltl
  • Patent number: 6177158
    Abstract: A tubular film for encasing food. The tubular film comprises a material which has been regenerated from a viscose solution. The tubular material is longitudinally stretched by from +8 to +40 percent and transversely stretched by from −20 to +40 percent while wet and the stretch is maintained during drying, said transverse stretch and longitudinal stretch being sufficient to obtain a surface area increase of at least 10 percent from the point of regeneration. In general, the tubular material has a wall thickness of from about 60 to about 90 percent of the same tubular material except without the combined stretch. The invention also includes the method for making the tubular material by stretching the regenerated tubular material while wet and maintaining the stretch during drying.
    Type: Grant
    Filed: May 20, 1998
    Date of Patent: January 23, 2001
    Assignee: Teepak Investments, Inc.
    Inventors: Mark van der Bleek, David Pohl
  • Patent number: 6165401
    Abstract: The invention relates to a process for the manufacture of cellulosic flat films and cellulosic membranes in the form of flat membranes whereby a solution of cellulose in an aqueous tertiary amine oxide is moulded in film form using an extrusion nozzle which has an oblong extrusion gap and is led into a precipitation bath via an air gap whereby the cellulosic flat film is formed in the precipitation bath, characterized in that the cellulosic flat film is stretched in the transverse direction after entering the precipitation bath.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: December 26, 2000
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Christian Schlossnikl, Peter Gspaltl, Johann Kalleitner, Gerold Riedl, Andreas Schweigart
  • Patent number: 6156253
    Abstract: A process for preparing fibers from an optically anisotropic solution containing either one of cellulose or cellulose derivatives by extruding the solution through a non-corroding spinneret and coagulating the resulting extrudates in a coagulant, the coagulant being a liquid which contains mostly water and to which cations have been added.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: December 5, 2000
    Assignee: Akzo Nobel N.V.
    Inventors: Marco Ypma, Hendrik Maatman, Hanneke Boerstoel
  • Patent number: 6136244
    Abstract: The invention pertains to a process for producing cellulose fibers and filaments from a spinnable cellulose-containing solution, by spinning the solution using a centrifuge, with the solution which is spun containing 94-100 wt. % of the following constituents:cellulose,phosphoric acid and/or its anhydrides, andwater.By means of this process cellulose fibers and filaments can be produced which have exceptionally favorable properties for both textile and industrial applications.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: October 24, 2000
    Assignee: Akzo Nobel N.V.
    Inventors: Sven Jorgen Rusticus, Eleonoor Van Andel
  • Patent number: 6117378
    Abstract: A process for the production of cellulose fibers, comprising the following steps:(A) dissolving a cellulose-containing material in an aqueous, tertiary amine-oxide to obtain a spinnable cellulose solution;(B) spinning said cellulose solution and passing it through an aqueous precipitation bath, whereby water-containing, swollen filaments are obtained;(C) squeezing said water-containing, swollen filaments at various points, so that at least two squeezing points per millimeter of filament length on average are achieved and(D) drying said squeezed filaments to cellulose fibers, wherein squeezing is carried out using a pressure big enough so that said squeezing points produced on the filament are preserved also on the dried fibre and may be seen as color variations when observed under linearly polarized light.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: September 12, 2000
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Markus Eibl, Dieter Eichinger
  • Patent number: 6106763
    Abstract: Process for producing cellulosic moldings such as fibers, foils, casings and beads from cellulose, wherein (a) the initial cellulose is hydrothermally treated with water in a water/cellulose ratio on a weight basis of at least 1 at a temperature in the range from about 100.degree. to about 200.degree. C. and under a pressure in the range from 0.1 to about 1.5 MPa; (b) the treated cellulose is dissolved in an aqueous solution of alkali hydroxide at a temperature of at least 0.degree. C. to form a homogenous cellulose solution containing from about 5% to about 10% by weight cellulose and at maximum 10% by weight alkali hydroxide, and (c) the alkaline cellulose solution is formed and coagulated by contacting it with an aqueous solution containing 1 to about 30% by weight of an acid. This fully ecological process avoids handling of toxic products or by-products and uses aqueous solvents instead of expensive organic solvents. The cellulose solution is stable for at least 48 hours.
    Type: Grant
    Filed: November 16, 1998
    Date of Patent: August 22, 2000
    Assignees: Institute of Chemical Fibres, Lurgi Zimmer AG
    Inventors: Henryk Struszczyk, Dariusz Wawro, Pawel Starostka, Wlodzimierz Mikolajczyk, Alojzy Urbanowski
  • Patent number: 6103162
    Abstract: The invention relates to a process for producing flexible cellulose fibres by spinning solutions of the cellulose through spinnerets over an air layer in an amine oxide-containing aqueous and/or alcoholic regenerating bath followed by drying, in which the damp threads from the spinneret are taken before drying through at least one post-treatment bath containing water and water-miscible alkanols, diols, triols or mixtures thereof, and a washing bath containing water, an alkanol, a diol or a triol.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: August 15, 2000
    Assignee: Fraunhofer-Gesellschaftzur Forderung der Angewandten Forschung e.V.
    Inventors: Konrad Frigge, Hans-Peter Fink, Peter Weigel, Ernst Walenta, Helmut Remde
  • Patent number: 6093355
    Abstract: Use in the manufacture of extruded lyocell articles of cellulose having a value of Pipe Flow Index (as defined) to Jet Flow Index (as defined) in the range from 0.85 to 6 can offer a number of advantages, particularly in cellulose solution transport and in spinning stability. Pipe Flow Index is designed to assess the flow performance of cellulose solution under low shear conditions typically experienced in transfer pipework. Jet Flow Index is designed to assess the flow performance of cellulose solution under high shear conditions typically experienced during extrusion.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: July 25, 2000
    Assignee: Acordis Fibres (Holdings) Limited
    Inventors: John Paul Newbury, Thomas Dovey
  • Patent number: 6068919
    Abstract: Cellulose fibres and filaments are prepared from a spinnable, cellulose-containing solution containing 94-100 wt. % cellulose, water, and phosphoric acid and/or anhydrides of phosphoric acid. The resulting cellulose fibres and filaments have an elongation break point greater than 7%. The cellulose-containing solution used to prepare the fibres and filaments may be either isotropic or anisotropic. The cellulose-containing solution is coagulated in a liquid containing water and cations, and the cations are preferably monovalent. Fibres and filaments prepared in this manner are especially suitable for use in textiles.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: May 30, 2000
    Assignee: Akzo Nobel N.V.
    Inventors: Marco Ypma, Jan Barend Westerink, Hendrik Maatman, Hanneke Boerstoel, Jannes Veurink
  • Patent number: 6048479
    Abstract: A process for manufacturing cellulose fibers or yarns with a reduced tendency to form fibrils includes treating fibers or yarns, which are washed after the filament forming process but not yet dried, with a cross-linking agent. The process includes treating the fibers or yarns with reactive polysiloxanes which are modified with amino, polyalkylene oxide, epoxy or carboxyl functional groups and which cross-link with themselves. The process is particularly suitable for fibers produced according to the NMMO process.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: April 11, 2000
    Assignee: Akzo Nobel NV
    Inventor: Abdulmajid Hashemzadeh
  • Patent number: 6042767
    Abstract: In a process for manufacturing a cellulosic yarn by spinning of a solution of cellulose in a tertiary amine oxide, the solution possibly containing water and/or a stabilizer, to form fibers or filaments, coagulating, washing, and drying, the yarns are treated prior to drying with an aqueous alkaline solution for a period less than 20 seconds.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: March 28, 2000
    Assignee: Akzo Nobel NV
    Inventors: Abdulmajid Hashemzadeh, Peter Raidt
  • Patent number: 6019925
    Abstract: A method for producing cellulosic dialysis membranes in the form of flat, tubular, or hollow fiber membranes by spinning a spinning solution of cellulose and/or modified cellulose, a tertiary amine oxide, and additional liquids and additives such as stabilizers, pore formers and the like is provided. The method operates at high takeoff speed and produces membranes for the low, middle, and high flux ranges. The membranes show practically no aging and have a stable structure. The oxidative breakdown of cellulose in the manufacture of the membranes is extremely low and hemocompatability is very good.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: February 1, 2000
    Assignee: Akzo Nobel NV
    Inventors: Michael Diamantoglou, Martin Nywlt, Winfried Holz
  • Patent number: 5997790
    Abstract: The disclosure describes a process for the preparation of regenerated cellulose filaments from an anisotropic solution including cellulose formate, phosphoric acid, and formic acid in which the formed cellulose formate filaments are dried to a moisture content of not more than 15% prior to regeneration and after regeneration the filaments are washed and dried under low tension. In this manner cellulose multifilament yarns of high breaking load and high elongation at break can be obtained, which in addition have a very regular linear density.
    Type: Grant
    Filed: May 19, 1998
    Date of Patent: December 7, 1999
    Assignee: Michelin Recherche et Technique S.A.
    Inventors: Gerardus Hendricus Vos, Bernardus Maria Koenders, Hanneke Boerstoel
  • Patent number: 5993710
    Abstract: The invention pertains to a process for manufacturing cellulose molded mers wherein a solution dissolved in amine oxides is shaped in a nozzle and the shaped solution is led after an air gap into a precipitation medium. The molded solution is passed successively through at least two precepitation media, which are selected so that a slower coagualation takes place at least in the first precipitation medium than the final precipitation medium.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: November 30, 1999
    Assignee: Fraunhofer-Gesellschaft zur Forderung der Angewandten Forschung e.V.
    Inventors: Peter Weigel, Hans-Peter Fink, Hans Joachim Purz, Konrad Frigge, Ulrich Wachsmann, Martin Nywalt
  • Patent number: 5968433
    Abstract: The invention is a process for spinning solutions of cellulose carbamate by extruding the solution through a spinneret into a precipitation bath, coagulating the cellulose carbamate fibers thus formed and drawing off the fibers by mechanical means, where the fibers are enveloped from the outlet from the spinneret to the outlet from the precipitation bath in a stream of precipitating medium flowing in the same direction, where the velocity of flow of the precipitation medium where the fibers exit the spinneret (plane X1) amounts to 0.1 to 0.8 times the draw-off speed of the fibers, and the velocity of flow of the precipitation medium where the fibers exit the precipitation bath (plane X3) amounts to 0.96 to 1.1 times the draw-off speed of the fibers.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: October 19, 1999
    Assignee: Zimmer Aktiengesellschaft
    Inventors: Marco Belch, Gerhard Keunecke, Juergen Wack
  • Patent number: 5968434
    Abstract: To prepare cellulose mouldings, a solution of cellulose in a tertiary amine-oxide is moulded in a hot state and the moulded solution is introduced into a precipitation bath in order to precipitate the contained cellulose, wherein the hot moulded solution is cooled before introduction into the precipitation bath. Cooling occurs immediately after the moulding process and preferably consists of blowing air horizontally on to the cellulose moulding. The process according to the invention allows spinning of the cellulose solution with a high fiber density without the spun fibers sticking together after emerging from the spinneret. In spite of the high fiber density, it furthermore allows the use of a long air gap between the spinneret and the precipitation bath, by which means sufficient time is generated in the spinning process to affect the textile properties of the fibers by drawing at the die (FIG. 1).
    Type: Grant
    Filed: June 10, 1998
    Date of Patent: October 19, 1999
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Stefan Zikeli, Ernst Rauch, Hermann Koberger, Friedrich Ecker, Hartmut Ruf, Raimund Jurkovic, Franz Schwenninger
  • Patent number: 5958320
    Abstract: Cellulosic fibers made from a solution of cellulose in a tertiary amine oxide and optionally water and which have a low tendency to fibrillate are produced by coagulating the fibers in at least two stages. The residence time of the fibers in the first coagulation stage is adjusted so that on leaving the first coagulation stage only the adhesiveness of the surface of the solution formed into fibers has been counteracted. In subsequent coagulation stages, the fibers are kept in a slack state. On leaving the final coagulation stage, the fibers have been thoroughly coagulated. The cellulosic fibers have a new structure and apart from a very low tendency to fibrillate, they possess a high dyeing level.
    Type: Grant
    Filed: January 7, 1998
    Date of Patent: September 28, 1999
    Assignee: Akzo Nobel NV
    Inventors: Hans-Jurgen Pitowski, Ulrich Wigand Wachsmann
  • Patent number: 5951933
    Abstract: The invention provides improvements in processes for film and fiber production involving precipitating cellulose from tertiary amine oxide solutions wherein a water soluble polymer is incorporated into the solution in an amount sufficient to slow precipitation of the cellulose during separation of the cellulose from the tertiary amine oxide.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: September 14, 1999
    Assignee: Alfacel s.a.
    Inventors: Alan David Stall, Albin F. Turbak
  • Patent number: 5951932
    Abstract: A method of producing lyocell fibers by spinning a solution of cellulose in an organic solvent through an air gap and into a spin bath in which there is provided a cross-draught of air in the air gap.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: September 14, 1999
    Assignee: Acordis Fibres (Holdings) Limited
    Inventors: Patrick Arthur White, Malcolm John Hayhurst, Alan R Owens, Ian David Roughsedge, Richard James Davies, Alan Sellars, Jacqueline Fave MacDonald, Michael Colin Quigley, Ralph Draper, Ronald Derek Payne
  • Patent number: 5939000
    Abstract: A method of producing lyocell fibres by spinning a solution of cellulose in an organic solvent through an air gap and into a spin bath in which there is provided a cross-draught of air in the air gap.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: August 17, 1999
    Assignee: Acordis Fibres (Holdings) Limited
    Inventors: Patrick Arthur White, Malcolm John Hayhurst, Alan R Owens, Ian David Roughsedge, Richard James Davies, Alan Sellars, Jacqueline Faye MacDonald, Michael Colin Quigley, Ralph Draper, Ronald Derek Payne
  • Patent number: 5938971
    Abstract: Liquid-crystal solutions comprising cellulose dissolved in a solvent agent. They contain more than 10% by weight of cellulose, and are optically anisotropic at rest and at room temperature. The solvent agent contains more than 85% by weight of at least one phosphoric acid, this phosphoric acid or all of these phosphoric acids having the following average formula :?n(P.sub.2 O.sub.5), p(H.sub.2 O)!,with 0.33<(n/p)<1.0.A method of obtaining such solutions. Production of fibers or films from these solutions. Assemblages of such fibers of films. Articles reinforced by such fibers or films or assemblages, said articles being in particular tire casings.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: August 17, 1999
    Assignee: Michelin Recherche et Technique S.A.
    Inventors: Rima Huston, Jean-Paul Meraldi, Fabio Urso, Philippe Esnault
  • Patent number: 5919412
    Abstract: The invention is an amine-oxide process for the production of a cellulose moulded body, wherein a suspension of cellulose in an aqueous tertiary amine-oxide is converted into a cellulose solution which is moulded and passed through an aqueous precipitation bath. A moulded body is obtained which, optionally after washing, is treated with a crosslinking agent. The cellulose solution contains a substance whereby the crosslinking agent may be activated. The process according to the invention allows the production of fibres having effectively controllable fibrillation properties.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: July 6, 1999
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Heinrich Firgo, Eduard Mulleder, Sigrid Seidl
  • Patent number: 5902532
    Abstract: Process for manufacturing cellulose formed objects, whereby a solution of cellulose is formed in the warm state in a tertiary amine N-oxide and, if necessary, water and the formed solution is cooled with air before introducing it into a coagulation bath. Conditioned air is employed for cooling which exhibits a water content of 0.1 to 7 g water vapor per kg dry air and whose relative humidity amounts to less than 85%.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: May 11, 1999
    Assignee: Akzo Nobel NV
    Inventor: Jurgen Pitowski
  • Patent number: 5891375
    Abstract: The invention provides improvements in processes for film and fiber production involving precipitating cellulose from tertiary amine oxide solutions wherein an ester is incorporated into the solution in an amount sufficient to slow precipitation of the cellulose during separation of the cellulose from the tertiary amine oxide.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: April 6, 1999
    Assignee: Alfacel s.a.
    Inventors: Alan David Stall, Albin F. Turbak
  • Patent number: 5891370
    Abstract: A process for manufacturing formed objects such as fibers, filaments, yarns, films, membranes in form of flat membranes, hose membranes and hollow fiber membranes and the like, involves pressing cellulose solutions in an amine oxide of a tertiary amine and if necessary water, in particular in N-methylmorpholine-N-oxide and water, through a nozzle and precipitating the solutions in a coagulation bath and washing the formed objects obtained. The coagulation bath liquid and the washing water is processed, if necessary, for recovery of the amine oxide of the tertiary amine. Hydrogen peroxide, peroxyethanoic acid, ozone or chlorine dioxide is added to the coagulation bath and/or the washing water. The substances added can preferably be decomposed catalytically or by enzymes prior to the recovery process of the water and the solvent.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: April 6, 1999
    Assignee: Akzo Nobel NV
    Inventors: Hans-Georg Connor, Derek Budgell
  • Patent number: 5868985
    Abstract: A process for manufacturing cellulose fibers by extrusion of a spinning solution, containing dissolved cellulose, into a gaseous medium through a predetermined gas zone, with subsequent immersion in and guidance through a coagulation bath over a predetermined coagulation zone, drawing the cellulose fibers obtained and winding them up, characterized in that after the gas zone the extruded spinning solution is immersed in a coagulation bath accelerated to a predetermined velocity and flowing laminarly at least approximately in the direction of the extruded spinning solution, whereby the coagulation liquid is fed laterally into the path of the spinning solution and the flow direction of the spinning solution and the coagulation liquid is kept approximately parallel throughout the entire coagulation zone, and in that the cellulose fibers obtained are laterally deflected upon leaving the coagulation zone and then wound up.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: February 9, 1999
    Assignee: Akzo Nobel NV
    Inventor: Gunter Frischmann
  • Patent number: 5863652
    Abstract: A tobacco smoke filter material comprises a fibrillated cellulose ester fiber with an average fiber diameter of 15 to 250 .mu.m and a BET specific surface area of 0.5 to 4.5 m.sup.2 /g. The fibrous cellulose ester content of the material may for example be not less than 20 weight %. The cellulose ester fiber is provided by, for example, extruding a cellulose ester solution from a nozzle into a precipitating agent for the particular cellulose ester and subjecting the extrudate to a shear force. This filter material can be used in the form of, for example, a filament, web or sheet to provide a tobacco smoke filter which assures good smoking qualities and excellent wet disintegratability.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: January 26, 1999
    Assignee: Daicel Chemical Industries Ltd.
    Inventors: Hiroyuki Matsumura, Syu Shimamoto, Tohru Shibata
  • Patent number: 5863478
    Abstract: The invention is concerned with a process for the production of cellulose fibers wherein a solution of cellulose in a tertiary amine-oxide is extruded through spinning holes of a spinneret, whereby filaments are extruded, the extruded filaments are conducted across an air gap, a precipitation bath and a drawing device whereby the filaments are drawn, the drawn filaments are further processed into cellulose fibers, the drawn filaments being exposed during further processing to a tensile stress in longitudinal direction not exceeding 5.5 cN/tex.
    Type: Grant
    Filed: October 30, 1997
    Date of Patent: January 26, 1999
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Hartmut Ruf, Christoph Schrempf
  • Patent number: 5858285
    Abstract: The invention is concerned with a process for the production of an aqueous amine-oxide solution used in the amine-oxide process for the production of a mouldable cellulose solution, wherein aqueous, amine-oxide containing solutions produced in said amine-oxide process particularly as precipitation baths are purified and concentrated, characterized in that a microbiocide agent is added to said aqueous, amine-oxide containing solutions before, during or after purification.
    Type: Grant
    Filed: April 15, 1997
    Date of Patent: January 12, 1999
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Johann Manner, Heinrich Firgo, Bruno Mangeng, Eduard Mulleder, Wolfram Kalt
  • Patent number: 5851394
    Abstract: A blood purification membrane having a membrane thickness of 10 to 35 .mu.m, an inner diameter of 100 to 300 .mu.m, a porosity of 50 to 85%, a water permeability (ultrafiltration rate) at 37.degree. C. of not less than 20 ml/m.sup.2 .multidot.Hr.multidot.mmHg and a sieving coefficient of albumin of not more than 0.01, a substantially homogeneous interior structure, and a smooth surface structure. A process for producing the membrane and a module are also provided.
    Type: Grant
    Filed: December 18, 1995
    Date of Patent: December 22, 1998
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Kazuhisa Shibata, Motoki Kyo, Hidehiko Sakurai, Makoto Ohno
  • Patent number: 5837184
    Abstract: Process for the production of cellulose fibres having a reduced tendency to fibrillation, in which a solution of cellulose in a tertiary amine-oxide is spun into fibres and the freshly spun fibres are contacted with a textile agent comprising at least two reactive groups, and are heat-treated, characterized in that the heat treatment is carried out by means of irradiation with electromagnetic waves.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: November 17, 1998
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Heinrich Firgo, Markus Eibl, Johann Schickermuller
  • Patent number: 5827463
    Abstract: The disclosure describes a process for the manufacture of cellulosic moulded bodies in which cellulose is dissolved in a mixture of a tertiary amine oxide and a non-solvent for cellulose, e.g. water. The solution is extruded via a moulding tool and the filaments received are led via an air gap to a precipitation bath whilst being drawn. The process is characterised in that the precipitation bath substantially comprises a non-aqueous solvent for the tertiary amine oxide, whereby the molecular weight of the non-aqueous solvent is larger than that of the tertiary amine oxide. In this manner, solvent-spun fibers with a lower fibrillation tendency can be obtained. Polyethylene glycols are preferably used.
    Type: Grant
    Filed: June 21, 1996
    Date of Patent: October 27, 1998
    Assignee: Lenzing Aktiengesellschaft
    Inventor: Hartmut Ruf
  • Patent number: 5804120
    Abstract: Celluloe extrudates can be made from an optically anisotropic solution containing 94-100 wt % of: cellulose; phosphoric acid and/or its anhydrides; and water by extruding the solution, coagulating the formed extrudates, and then aftertreating those extrudates so that they have a degree of acidity which at least equals 7. Fibres obtained by such a process possess particularly good thermal stability and are suitable for use as a reinforcing material.
    Type: Grant
    Filed: February 19, 1997
    Date of Patent: September 8, 1998
    Assignee: Akzo Nobel N.V.
    Inventors: Hanneke Boerstoel, Marco Ypma
  • Patent number: 5795522
    Abstract: This invention relates to a process for the production of a cellulose molded body according to the amine-oxide process, which results in a molded body having reduced and effectively controllable fibrillation properties.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: August 18, 1998
    Assignee: Lenzing Atkiengesellschaft
    Inventors: Heinrich Firgo, Sigrid Seidl, Peter Bartsch, Berndt Koll, Eduard Mulleder
  • Patent number: 5795488
    Abstract: The invention is concerned with a process for transporting a solution of cellulose in an aqueous tertiary amine-oxide through a component wherein said cellulose solution has different flow rates in said component, characterized in that an outlet wherethrough part of said cellulose solution is discharged from said component is provided at a point within said component whereat said flow rate is relatively low. (FIG.
    Type: Grant
    Filed: September 19, 1996
    Date of Patent: August 18, 1998
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Wolfram Kalt, Johann Manner, Heinrich Firgo, Franz Schwenninger
  • Patent number: 5792399
    Abstract: A molding, particularly a fiber or foil molding, of cellulose regenerated an amino-oxide process provides that the cellulose contains 0.02 to 30% mass of a polyalkylene imine derivative. In addition to improved stabilization of the molding compound, the molding or fiber exhibits improved properties, such as an anion exchange capacity, fungistatic properties and an improved hydroblast resistance.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: August 11, 1998
    Assignee: Ostthuringische Materialprufgesellschaft fur Textil und Kunststoffe mbH
    Inventors: Frank Meister, Christoph Michels, Horst Kramer
  • Patent number: 5788939
    Abstract: A process for the production of a cellulose moulded body, particularly cellulose fibers, wherein a cellulose-containing material is introduced into an aqueous solution of a tertiary amine-oxide to suspend said cellulose-containing material, water is withdrawn from the suspension while intensively mixing it and subjecting it to elevated temperature and reduced pressure until a solution of cellulose is produced, and the solution is moulded using a forming tool, particularly a spinneret, and passed into a precipitation bath to precipitate the cellulose dissolved, and is characterized in that a suspension containing a cellulose-containing material which has been exposed to an electron radiation is used to produce the cellulose solution. (Fig.
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: August 4, 1998
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Eduard Mulleder, Christoph Schrempf, Gabriele Schild
  • Patent number: 5783121
    Abstract: A preparation of a polymer solution comprising the steps of: mixing a polymer with a solvent to swell the polymer in the solvent; cooling the swelled mixture to a temperature of -100.degree. to -10.degree. C.; and then warming the cooled mixture to a temperature of 0.degree. to 120.degree. C. to dissolve the polymer in the solvent. The swelled mixture is cooled at a rate of faster than 1.degree. C. per minute, or the cooled mixture is warmed at a rate of faster than 1.degree. C. per minute. Apparatuses for the preparation of a polymer solution are also disclosed.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: July 21, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hidekazu Yamazaki, Tadahiro Tsujimoto, Yukihiro Katai
  • Patent number: 5773035
    Abstract: A modular tubular cellulosic casing die that includes interchangeable parts, and adjustable die openings having an inner lip that can be centered and vertically adjusted relative to the die's outer lip.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: June 30, 1998
    Assignee: Alfacel s.a.
    Inventors: Alan David Stall, Algis S. Lewkow
  • 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: 5766530
    Abstract: The invention is concerned with a process for the production of cellulose moulded bodies wherein a suspension of cellulose in an aqueous solution of a tertiary amine-oxide is transformed into a mouldable solution, said solution being extruded by means of a forming tool and conducted into a precipitation bath. The process is characterized in that at least part of the materials in devices and pipes for the transportation and processing of the solution, which material is in contact with the mouldable solution contains at a minimum of 90% up to a depth of at least 0,5 .mu.m, preferably more than 1 .mu.m, at least one element of the group consisting of titanium, zirconium, chromium and nickel in elementary form and/or in the form of compounds provided that the remaining of the material does not contain any of the elements of the group consisting of copper, molybdenum, tungsten or cobalt.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: June 16, 1998
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Wolfram Kalt, Johann Manner, Arnold Nigsch, Heinrich Firgo, Christian Hager, Wolfgang Helmut Schkorwaga
  • Patent number: 5762846
    Abstract: A process for spinning a fully water washed fluorinated olefinic polymer intermediate fiber structure from a mixture of an aqueous dispersion of particles of the fluorinated olefinic polymer and a solution of a cellulosic ether.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: June 9, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Nicole Lee Blankenbeckler, Joseph Michael Donckers, II, Warren Francis Knoff
  • 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: 5744090
    Abstract: A method of making a conductive fiber in which the conductive fiber is formed from a mixture including at least one fiber forming material and conductive magnetic materials, and the conductive magnetic materials are migrated toward the periphery of the fiber by application of a magnetic field to the fiber. The conductive fibers having the conductive magnetic materials located at the periphery of the fiber are preferably incorporated into an electrostatic cleaning device for use in an electrostatographic printing device.
    Type: Grant
    Filed: January 13, 1997
    Date of Patent: April 28, 1998
    Assignee: Xerox Corporation
    Inventors: Lewis O. Jones, Joseph A. Swift, Ronald F. Ziolo
  • Patent number: 5723081
    Abstract: A process for preparing a dispersion spun fluorinated polymer fiber wherein the intermediate fiber structure, immediately before sintering, contains primarily ions characterized as fugitive ions.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: March 3, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Nicole Lee Blankenbeckler, Joseph Michael Donckers, II, Warren Francis Knoff
  • Patent number: 5698151
    Abstract: To prepare cellulose fibres, a solution of cellulose in a tertiary amine-oxide is shaped in hot condition to give filaments, the filaments are cooled and then introduced into a precipitation bath in order to precipitate the dissolved cellulose, whereby the shaped solution is exposed to an essentially laminar gas stream (FIG. 2a) for cooling before introduction into the precipitation bath.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: December 16, 1997
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Stefan Zikeli, Friedrich Ecker, Franz Schwenninger, Raimund Jurkovic, Hartmut Ruf
  • Patent number: 5662858
    Abstract: Process for the production of cellulose fibres having a reduced tendency to fibrillation, in which a solution of cellulose in a tertiary amine-oxide is spun into fibres and the freshly spun fibres are contacted with a textile agent comprising at least two reactive groups, and are heat-treated, characterized in that the heat treatment is carried out by means of irradiation with electromagnetic waves.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: September 2, 1997
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Heinrich Firgo, Markus Eibl, Johann Schickermuller
  • Patent number: 5658525
    Abstract: In a method for forming a cellulose tube suitable for use as a food casing, in which a solution of nonderivatized cellulose, tertiary amine N-oxide and water is extruded through a die gap and the extruded tube is downwardly drawn through an air gap while being internally cooled and then is passed into a water bath, the tube transverse direction tensile strength being increased by drawing the extruded tube through an air length of at least about five inches and exposing the exterior surface of the extruded tube to cooling air in the air gap.
    Type: Grant
    Filed: August 4, 1995
    Date of Patent: August 19, 1997
    Assignee: Viskase Corporation
    Inventors: Edward Makoto Kajiwara, Norman Abbye Portnoy, Paul Edmund Ducharme, Jr.