Cellulose Derivatives Patents (Class 264/187)
  • Publication number: 20040234806
    Abstract: A moldable pellet used for making high impact, non-abrasive recyclable structural composites consisting of a thermoplastic polymer or polymers, with or without fillers and additives, and a synthetic cellulosic fiber in yarn or tow form such as Rayon or Lyocell. The concentration of cellulose fiber within the pellet may vary from approximately 2-80 percent by weight or higher. This moldable pellet is suitable for molding in current molding applications such as, but not limited to, injection molding, extrusion compression molding, and compression molding.
    Type: Application
    Filed: May 18, 2004
    Publication date: November 25, 2004
    Inventors: Frank R. Cichocki, James L. Thomason, Terry L. Cheney
  • 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: 6814904
    Abstract: Process for producing formed cellulosic articles, particularly fibers and filaments, comprising a) dissolving cellulose in an aqueous solution of a tertiary amine oxide, especially N-methyl-morpholine N-oxide, and b) extruding the cellulose solution through an extrusion die via an air gap into a precipitation bath with precipitation of the formed articles, said cellulose solution and/or said precipitation bath containing a tenside, characterized in that in the step b) the tenside content c of the cellulose solution and/or of the precipitation bath is in the range 100 ppm>c>5 ppm, and the width of the air gap is in the range from 2 to 20 mm. With this process the air gap width can be considerably reduced without deterioration of the properties of the fibers/filaments.
    Type: Grant
    Filed: August 22, 2001
    Date of Patent: November 9, 2004
    Assignee: Zimmer AG
    Inventors: Ralf-Uwe Bauer, Frank-Gunter Niemz
  • Publication number: 20040207110
    Abstract: In accordance with the present invention, lyocell products can be made with unbleached pulps resulting in products with high amounts of hemicellulose and high amounts of lignin as compared to conventional lyocell products. The lyocell products of the present invention are advantageously less expensive to produce but retain the desirable strength of conventional lyocell products.
    Type: Application
    Filed: April 16, 2003
    Publication date: October 21, 2004
    Inventors: Mengkui Luo, Amar Neogi
  • Patent number: 6797100
    Abstract: The invention relates to a film tube (10) based on cellulose which is produced by extruding an aqueous cellulose-N-methyl-morpholine-N-oxide (NMMO) solution through a ring nozzle (21) onto a lining (3). The film tube (10) is manufactured by means of a vertically descending spinning in a spinning vat (12) in which a spinning bath (11) is located. The film tube (10) which is submerged in the spinning bath (11) passes through an air gap (9) between the underside of a nozzle block (7) and the upper surface of the spinning bath (11) and, internally, is pressurized, supported and slightly stretched in a transversal manner by compressed air. The film tube (10) is filled with an inner bath solution (31) via a supply tube (18). An idle roller (13) is situated near the bottom of the spinning vat (12) in order to guide the film tube (10) around and, afterwards, out of the spinning vat (12) in an upward sloping manner. The film tube is laid flat along a contact section (27) of the idle roller (13).
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: September 28, 2004
    Assignee: Kalle GmbH & Co. KG
    Inventors: Herbert Gord, Klaus-Dieter Hammer, Helmut Sattler, Rainer Neeff
  • Patent number: 6793689
    Abstract: The present disclosure relates to novel dyed cellulosic moulded bodies, in particular to fibers or films, containing a heavy-metal-containing colorant, which, according to the thermal stability test described herein, reduces the rise temperature of a cellulose solution in a tertiary amine oxide by 10° C. at most, in particular by 5° C. at most. The moulded bodies according to the disclosure may be produced in accordance with the amine-oxide process.
    Type: Grant
    Filed: February 8, 2002
    Date of Patent: September 21, 2004
    Assignee: Lenzing Aktiengesellschaft
    Inventor: Hartmut Rüf
  • Patent number: 6756001
    Abstract: The invention concerns a coagulating agent for liquid crystal solutions with a base of cellulose substances, characterised in that it contains at least one water soluble additive selected from the group consisting of ammonia, amines of salt of these compounds, the additive being such that the pH of the said coagulating agent is greater than 6. A preferable additive is a salt elected from the group consisting of ammonium formates, acetates and phosphates, mixed salts of these compounds, or mixtures of these constituents, in particular diammonium orthophosphates (NH4)2HPO4. The invention also concerns a method for spinning a liquid crystal solution with a base of cellulose substances, using a coagulating agent as per the invention, in particular the method called the “dry-jet-wet-spinning” as well as spun articles, fibers or films, obtained by these methods.
    Type: Grant
    Filed: June 13, 2002
    Date of Patent: June 29, 2004
    Assignee: Michelin et Cie
    Inventors: Jean-Paul Meraldi, Rima Huston, Vlastimil Cizek
  • Patent number: 6746641
    Abstract: Process for producing formed cellulosic articles, such as fibers, filaments, sheetings, membranes or tubes, comprising a) extruding a solution of cellulose in an aqueous amine oxide, particularly N-methylmorpholine N-oxide, through an extrusion die via an air gap and coagulating the formed article in an aqueous precipitation bath containing amine oxide, and b) passing the formed article through at least one washing stage for removing residual amine oxide from the article, characterized in that the liquor of the precipitation bath in the precipitation stage and/or the washing liquor of the washing stage(s) is treated with ultra-violet radiation. In this manner the formation and growth of coatings, films and slime deposits caused by microorganisms is avoided on parts of the plant which come into contact with said liquors containing the amine oxide.
    Type: Grant
    Filed: August 28, 2001
    Date of Patent: June 8, 2004
    Assignee: Zimmer AG
    Inventors: Holger Gunkel, Michael Mooz
  • Publication number: 20040099981
    Abstract: The invention relates to a method and a device for producing substantially endless fine threads from polymer solutions, especially spinning material for lyocell, wherein the spinning material is spun from at least one spinning hole or a spinning slot. The spun thread or film is drawn by high-speed accelerated gas flows using a Laval nozzle whose narrowest cross-section is located beneath the point where the spinning material exists. The threads are arranged on a strip in the form of a non-woven or are taken up in the form of a yarn and are subsequently separated in spinning baths by means of solvents.
    Type: Application
    Filed: December 16, 2003
    Publication date: May 27, 2004
    Inventor: Luder Gerking
  • Patent number: 6720057
    Abstract: The invention described here concerns a process to permit the manufacture of a cellulose fibre from hydrate cellulose with an extremely large surface area which may be used for the preparation of a fabric characterized by a high absorptive power, good liquid-retention properties, high grease-solvent properties as well as particle-absorbing properties, which is suitable for making products that are themselves easy to clean, which can be used for cleaning and decontamination as well as to reduce the surface tension of water and which can be disposed of without damage to the environment.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: April 13, 2004
    Inventors: Achim Neumayr, Herbert Hasl
  • Publication number: 20040051202
    Abstract: The present invention relates to a method and an apparatus for extruding continuously molded bodies, wherein an extrusion solution, in particular an extrusion solution containing water, cellulose and a tertiary amine oxide, is extruded through an extrusion orifice into a continuously molded body and is then deflected by means of a deflector (7). To improve the quality of the continuously molded bodies produced by the method or apparatus of the invention, the extrusion orifices are arranged in a row such that the individual, continuously molded bodies exit in the form of a curtain (3) form the extrusion head. This curtain is then deflected by the deflector.
    Type: Application
    Filed: August 11, 2003
    Publication date: March 18, 2004
    Inventors: Stefan Zikeli, Friedrich Ecker
  • Publication number: 20040051200
    Abstract: Process for producing fibres, film, casings and other products from modified soluble cellulose wherein the initial cellulose is hydrothermally treated at a temperature in the 100-200° C. range, under a pressure in the range from about 0.1 to 1.5 Mpa in a water/cellulose ration on a weight basis of at least 1:1 in the presence of a complex activator composed of Lewis acids and/or bases and/or their salts in an amount of at least 0.0001% by weight calculated on cellulose. The obtained modified cellulose pulp after, a possible purification, is in a dry or never dried condition, dissolved in an aqueous solution of alkali metal hydroxides. The dissolving is carried out at a temperature not lower than 0° C. for 1-120 minutes to obtain a homogenous spinning solution with the cellulose concentration at least 1% by weight. The alkaline cellulose solution is filtered, deaerated and coagulated by contacting it with water or aqueous acidic solutions.
    Type: Application
    Filed: September 5, 2003
    Publication date: March 18, 2004
    Inventors: Henryk Struszczyk, Dariusz Wawro, Alojzy Urbanowski, Wlodzimierz Mikolajczyk, Pawel Strarostka
  • Patent number: 6706224
    Abstract: The invention relates to a process for the production of a spunlaid fabric containing solvent-spun cellulosic fibers.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: March 16, 2004
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Heinrich Firgo, Rudolf Kraft, Harmut Rüf, Christian Schlossnikl
  • Patent number: 6706237
    Abstract: The present invention is directed to methods of making lyocell fibers. In particular, the process includes reducing the average degree of polymerization of a pulp to about 200 to 1100 without substantially reducing the hemicellulose content of the pulp, and reducing the copper number to less than 2.0.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: March 16, 2004
    Assignee: Weyerhaeuser Company
    Inventors: Mengkui Luo, Vincent A. Roscelli, Amar N. Neogi, James E. Sealey, II, Richard A. Jewell
  • Publication number: 20040021246
    Abstract: The present invention relates to an apparatus and a method as well as a system for extruding continuously molded bodies for producing filaments or staple fibers from an extrusion solution, such as a cellulose solution containing water, cellulose and tertiary amine oxide such as N-methylmorpholine N-oxide. In comparison with the methods known from the prior art, profitability can be increased in the production of continuously molded bodies (3) if the extrusion rate v is set to a value v=B·T0.33·10,000·(1/r2). In a system, profitability can be enhanced if the number r of rows is r=[(B/v)·10,000·T0.33]1/2. T is here the fiber titer in T dtex, v the extrusion rate in m/min, r the number of the rows of extrusion duct orifices (12), and B an operational parameter which is not more than 4 and at least 0.5.
    Type: Application
    Filed: July 14, 2003
    Publication date: February 5, 2004
    Inventors: Stefan Zikeli, Friedrich Ecker
  • 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
  • Patent number: 6645409
    Abstract: The invention relates to a process for the production of cellulosic fibers from solutions of cellulose in an aqueous tertiary amine oxide whereby the extruded fibers are led through a precipitating bath and cut and the cut fibers are passed through a series of water baths in the form of a fleece and then dried, whereby the wash baths are connected to each other and fresh washing liquor is applied to the last wash bath and led in countercurrent with the transportation direction of the fibre fleece to the first wash bath. The process in accordance with the invention is characterised in that the pH value of each of these wash baths is maintained higher than 8.5.
    Type: Grant
    Filed: March 21, 2001
    Date of Patent: November 11, 2003
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Wilhelm Feilmair, Heinrich Firgo, Johann Männer
  • Publication number: 20030193109
    Abstract: The present invention relates to a method of producing a continuous moulding (11) making use of an extrusion solution containing preferably water, cellulose and a tertiary amine oxide. The extrusion solution is extruded through an extrusion-channel opening (10) so as to form a continuous moulding. The continuous moulding is conducted through an air gap (12) in which it is drawn. In order to increase the non-looping property and in order to reduce the fibrillation tendency, the present invention is so conceived that the mean acceleration and/or the mean heat flow density are controlled in accordance with predetermined formulae.
    Type: Application
    Filed: April 7, 2003
    Publication date: October 16, 2003
    Inventors: Stefan Zikeli, Friedrich Ecker
  • Publication number: 20030183976
    Abstract: This application relates to producing biaxially stretched tubular cellulose films for the food industry. In particular, the biaxial stretching is obtained by using rollers to stretch the casings longitudinally and to use increased air pressure inside the films to radially stretch the casings. The obtained product may also be cut to provide longitudinal strips for the production of smaller tubular films.
    Type: Application
    Filed: December 13, 2002
    Publication date: October 2, 2003
    Inventors: Ivo G. Hendriks, Roger H. Hendrikx, Stefan D. Beckers, Mark Vrijsen, Dirk M. Hellemans
  • Publication number: 20030173700
    Abstract: The invention relates to a process for the production of cellulosic fibres by extruding a solution of cellulose in a tertiary amine oxide through spinning holes of a spinning nozzle and conducting the extruded filaments into a precipitation bath via an air gap while they are drawn off, the filaments in the air gap being exposed to the flow of a gas. The invention is characterized in that for the temperature (T) of the gas before the contact with the filaments 60° C.<T<90° C. is correct.
    Type: Application
    Filed: December 27, 2002
    Publication date: September 18, 2003
    Inventors: Hartmut Ruf, Christoph Schrempf
  • Publication number: 20030168762
    Abstract: The present invention relates to a method for producing a continuously molded body (11) from an extrusion solution preferably containing water, cellulose and a tertiary amine. The extrusion solution is extruded through an extrusion duct orifice (10) to obtain a continuously molded body. The continuously molded body is passed through an air gap (12) in which it is stretched. To increase the loop strength and to reduce the tendency to fibrillate, the mean acceleration and/or the mean heat flow density are controlled according to the invention in accordance with predetermined formulae.
    Type: Application
    Filed: April 29, 2003
    Publication date: September 11, 2003
    Inventors: Stefan Zikeli, Friedrich Ecker
  • 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: 20030155673
    Abstract: The present invention relates to a spinning head (8) for spinning a spinning dope, which is provided with a tubular, thin-walled spinning capillary (7) having a discharge opening (94). The spinning dope used is e.g. a mixture of cellulose, tertiary amine oxide and water. In order to reduce the fibrillation tendency of the fibres spun by means of the spinning head and in order to increase the non-looping property, the present invention is so conceived that the spinning capillary (7) is heated directly close to the discharge cross-section (94). By means of this simple measure, it is possible to reduce the fibrillation tendency and to increase the non-looping property.
    Type: Application
    Filed: February 24, 2003
    Publication date: August 21, 2003
    Inventors: Stefan Zikeli, Friedrich Ecker
  • Publication number: 20030116882
    Abstract: Method for the production of cellulose fibers of —filaments from cellulose according to the dry-wet-extrusion method with aqueous amine oxides, especially N-methyl morpholine-N-oxide as solvent, where
    Type: Application
    Filed: October 29, 2002
    Publication date: June 26, 2003
    Inventors: Birgit Kosan, Christoph Michels
  • Patent number: 6579461
    Abstract: The invention relates to a process for the reprocessing respectively purification of aqueous solutions of a tertiary amine oxide, particularly of process waters, e.g. used precipitation baths, which occur during the production of cellulosic moulded bodies, comprising the separation of turbidifying agents and solid impurities from the solution. The process in accordance with the invention is characterised in that the turbidifying agents and impurities are at least partly separated by means of a flotation process.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: June 17, 2003
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Johann Männer, Rudolf Emeder, Christian Hager, Franz Nussbaumer, Thomas Endl, Johannes Kneissl
  • Patent number: 6565796
    Abstract: Disclosed is a method of sizing nonderivatized extruded cellulosic tubes by the use of a mandrel structure that includes a hollow sizing portion having openings which gather gas bubbles that may evolve at the interface between the extruded tube and the sizing portion and allows the gas to pass into the hollow interior of the mandrel. The mandrel contains a sizing portion larger than the extruded tube, which allows for improved sizing of nonderivatized extruded tubes that are used as casings.
    Type: Grant
    Filed: October 4, 2001
    Date of Patent: May 20, 2003
    Assignee: Viskase Corporation
    Inventors: Owen Joseph McGarel, Mickel E. Knight, Charles Joseph Mackus
  • Patent number: 6565788
    Abstract: The invention relates to a process for the production of cellulosic flat films whereby a solution of cellulose is extruded in an aqueous tertiary amine oxide by means of an extrusion die which has an extrusion gap whereby the solution is moulded in the shape of a film and the extruded solution is led via an air gap to a precipitation bath. The process in accordance with the invention is characterized in that an extrusion die is used which has an extrusion gap b of 220 &mgr;m≦b≦280 &mgr;m. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 &mgr;m, a width B of more than 30 cm, and a factor f of 65 or less, whereby f is defined as f=d*(MD/TD), d is used in &mgr;m and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm2) and TD for the tenacity of the film in the transverse direction (N/mm2).
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: May 20, 2003
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Peter Gspaltl, Christian Schlossnikl
  • Publication number: 20030062649
    Abstract: The invention relates to a stick of a tubular food casing based on cellulose. The casing is produced by the NMMO process. The stick is particularly stable and is thus suited for automatic filling devices such as those used for producing cooked or boiled sausages.
    Type: Application
    Filed: September 3, 2002
    Publication date: April 3, 2003
    Inventors: Klaus-Dieter Hammer, Herbert Gord, Rainer Neeff, Klaus Berghof, Markus Eilers, Reinhard Maron
  • Publication number: 20030062648
    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: Application
    Filed: September 18, 2002
    Publication date: April 3, 2003
    Inventors: Peter Weigel, Hans-Peter Fink, Michael Doss, Stefan Dominic Beckers, Roger Henri Hendrikx
  • Publication number: 20030054167
    Abstract: Disclosed is a process for producing water-insoluble cellulose fibers having high carboxyl content by reacting cellulose fiber in suspension with dicarboxylic acid anhydride or chloride in the presence of a basic catalyst. The fibers produced possess a unique combination of high carboxyl content in the range of 100 to 4000 meq/kg, and high average viscosity, in the range of 0.5 to 12 dl/g. The carboxylated cellulose fibers according the invention can be made with a combination of carboxyl content and average viscosity which are suitable for use in numerous applications, including absorbent products, health care products, specialty papers, adhesives, detergents, biodegradable fibers, precursors for aqueous coatings and ion exchange fibers.
    Type: Application
    Filed: August 3, 2001
    Publication date: March 20, 2003
    Inventor: Linfu Wang
  • Patent number: 6527987
    Abstract: It is an object of the present invention to overcome the problem of fibrillation which is a drawback found in solvent-spun regenerated cellulosic fibers and to thereby provide high-quality regenerated cellulosic fibers. The regenerated cellulosic fibers are produced by the use of a spinning dope of cellulose dissolved in a solvent containing N-methylmorpholine N-oxide under the conditions that the average degree of polymerization of cellulose contained in the spinning dope is held to 400 or lower and 5% to 30% by weight of the cellulose is adjusted to a degree of polymerization of 500 or higher. Thus a pseudo-liquid-crystalline phenomenon can be allowed to occur in the stretched filaments during spinning, so that the resulting regenerated cellulosic fibers have improved resistance to fibrillation as well as improved dyeability and feeling.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: March 4, 2003
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Kazuyuki Yabuki, Yoshikazu Tanaka, Hisato Kobayashi
  • Patent number: 6527997
    Abstract: A cellulose formate fiber of liquid-crystal origin, having a high elongation at break and having the following characteristics: a) under an optical polarizing microscope, its filaments have a banded structure typical of its liquid-crystal origin; b) it satisfies the following relationships: DS≧2; Ar≧8; Te<45; Mi>500; Er>10, DS being the degree of substitution of the cellulose with formate groups in the fiber (in %), Ar the elongation at break (in %) of the fiber, Te its tenacity (in cN/tex), Mi its initial modulus (in cN/tex) and Er its energy at break (in J/g). Also, a process for obtaining this cellulose formate fiber by “dry-jet-wet-spinning” of a liquid-crystal solution of cellulose formate, in which water is used as coagulating agent. A fiber of cellulose regenerated from cellulose formate which itself has a high value of elongation at break, and a process for obtaining this fiber.
    Type: Grant
    Filed: July 20, 2000
    Date of Patent: March 4, 2003
    Assignee: Michelin Recherche et Technique S.A.
    Inventors: Jean-Paul Meraldi, Vlastimik Cizek, Jean-Claude Aubry
  • 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
  • Patent number: 6517758
    Abstract: The invention relates to a process for the production of cellulosic moulded bodies in the form of flat or tubular films and cellulosic membranes in the form of flat or tubular films whereby a solution of cellulose in an aqueous tertiary amine oxide is extruded using an extrusion nozzle whereby the solution can as the case may be also contain additives such as stabilizing and softening agents, pore formers and so on whereby a moulded solution results which has two surfaces and the extruded moulded solution is led over a gap into a precipitation bath and drawn off from the precipitation bath. The process in accordance with the invention is characterized in that the two surfaces of the moulded solution in the gap are each exposed to at least one gaseous medium whereby the medium to which the first surface is exposed differs from the medium to which the second surface is exposed in composition, properties and/or the state of motion.
    Type: Grant
    Filed: January 28, 2000
    Date of Patent: February 11, 2003
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Peter Gspaltl, Christian Schlossnikl, Johann Kalleitner, Heinrich Firgo
  • Publication number: 20020189035
    Abstract: The present invention relates to novel dyed cellulosic molded bodies, in particular to fibers or films, containing a heavy-metal-containing colorant, which, according to the thermal stability test described above, reduces the rise temperature of a cellulose solution in a tertiary amine oxide by 10° C. at most, in particular by 5° C. at most. The molded bodies according to the invention may be produced in accordance with the amine-oxide process (FIG. 1).
    Type: Application
    Filed: February 8, 2002
    Publication date: December 19, 2002
    Applicant: LENZING AKTIENGESELLSCHAFT
    Inventor: Hartmut Ruf
  • Patent number: 6488876
    Abstract: The invention relates to a composition intended to be admixed to a moldable solution of cellulose in an aqueous tertiary amine oxide, which composition consists of solid particles, a mixture of a tertiary amine oxide and water, in which the solid particles are dispersed, and at least a further substance, with the proviso that the solid particles and said at least further substance are different from cellulose and that the content of water is such that no cellulose will precipitate when admixing the composition to the moldable cellulose solution. The composition according to the invention is storage stable to a high degree and suitable for introducing additives into the moldable cellulose solution.
    Type: Grant
    Filed: February 3, 1999
    Date of Patent: December 3, 2002
    Assignee: Lenzing Aktiengesellschaft
    Inventor: Harmut Rüf
  • Publication number: 20020167110
    Abstract: The invention relates to a device for the production of cellulosic tubular films by extruding a solution of cellulose in an aqueous tertiary amine oxide into a precipitant present below the device, which device comprises an extrusion die having a substantially annular extrusion gap, wherein a supply duct for precipitant and a discharge duct for used precipitant are provided in the interior of the ring formed by the extrusion gap, characterized in that the supply duct (3) for the precipitant terminates below the discharge duct (4) for the used precipitant.
    Type: Application
    Filed: June 27, 2002
    Publication date: November 14, 2002
    Applicant: LENZING AKTIENGESELLSCHAFT
    Inventors: Christian Schlossnikl, Peter Gspaltl, Alois Kofler
  • Patent number: 6444161
    Abstract: Disclosed is a mandrel structure for extruding a tube composed of a non derivatized cellulose. The mandrel includes a hollow sizing portion having openings which gather gas bubbles that may evolve at the interface between the extruded tube and the sizing portion and allows the gas to pass into the hollow interior of the mandrel.
    Type: Grant
    Filed: May 19, 2000
    Date of Patent: September 3, 2002
    Assignee: Viskase Corporation
    Inventors: Mark Griffith Williams, Larry Clyde Long, Owen Joseph Mc Garel, Ronald Joseph Jerantowski, James Joseph Albert
  • Publication number: 20020113336
    Abstract: A process of producing at least one filament of refractory material comprising: (a) preparing a spin mix of a solution of cellulose and particles of refractory material; (b) wet spinning the spin mix to form at least one filament of regenerated cellulose having at least a portion of the particles dispersed therein; and (c) heating the filament of regenerated cellulose to remove substantially all of the regenerated cellulose and to sinter the portion of the particles dispersed therein to form a filament of the refractory material.
    Type: Application
    Filed: April 24, 2002
    Publication date: August 22, 2002
    Inventors: Richard B. Cass, Thomas C. Allen, Roland R. Loh
  • Patent number: 6436325
    Abstract: A method of manufacturing a cellulose based fiber of high water-retentivity. The cellulose based fiber of high water rententivity is manufactured by mixing together a stock solution as a homogeneous mixture of a non-cellulose based material of high absorbency and a cellulose based material and a stock solution singly composed of cellulose based material by means of a nozzle. Then the mixture is formed into a complex fiber as a sheath-core type by spinning, elongation and refining the mixture.
    Type: Grant
    Filed: March 17, 2000
    Date of Patent: August 20, 2002
    Assignee: Uni-Charm Corporation
    Inventors: Tsutomu Kido, Noriyuki Kimura, Ichiro Takeuchi, Kazuya Umino
  • Publication number: 20020060382
    Abstract: The present invention is directed to methods of making lyocell fibers. In particular, the process includes reducing the average degree of polymerization of a pulp to about 200 to 1100 without substantially reducing the hemicellulose content of the pulp, and reducing the copper number to less than 2.0.
    Type: Application
    Filed: October 30, 2001
    Publication date: May 23, 2002
    Applicant: Weyerhaeuser Company
    Inventors: Mengkui Luo, Vincent A. Roscelli, Amar N. Neogi, James E. Sealey, Richard A. Jewell
  • Publication number: 20020045038
    Abstract: The invention relates to a process for the production of cellulosic flat films whereby a solution of cellulose is extruded in an aqueous tertiary amine oxide by means of an extrusion die which has an extrusion gap whereby the solution is moulded in the shape of a film and the extruded solution is led via an air gap to a precipitation bath. The process in accordance with the invention is characterised in that an extrusion die is used which has an extrusion gap b of 220 &mgr;m≦b≦280 &mgr;m. Moreover, the invention relates to flat films, obtainable by the amine oxide process with a thickness d of less than 20 &mgr;m, a width B of more than 30 cm, and a factor f of 65 or less, whereby f is defined as f=d*(MD/TD), d is used in &mgr;m and whereby MD stands for the tenacity of the film in the longitudinal direction (N/mm2) and TD for the tenacity of the film in the transverse direction (N/mm2).
    Type: Application
    Filed: April 20, 2001
    Publication date: April 18, 2002
    Applicant: LENZING AKTIENGESELLSCHAFT
    Inventors: Peter Gspaltl, Christian Schlossnikl
  • 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
  • Publication number: 20020008331
    Abstract: The invention relates to a process for the production of cellulosic fibres from solutions of cellulose in an aqueous tertiary amine oxide whereby the extruded fibres are led through a precipitating bath and cut and the cut fibres are passed through a series of water baths in the form of a fleece and then dried, whereby the wash baths are connected to each other and fresh washing liquor is applied to the last wash bath and led in countercurrent with the transportation direction of the fibre fleece to the first wash bath. The process in accordance with the invention is characterised in that the pH value of each of these wash baths is maintained higher than 8.5.
    Type: Application
    Filed: March 21, 2001
    Publication date: January 24, 2002
    Applicant: LENZING AKTIENGESELLSCHAFT
    Inventors: Wilhelm Feilmair, Heinrich Firgo, Johann Manner
  • Patent number: 6319457
    Abstract: A method and apparatus is disclosed for lacing an extruded tube of a non derivatized cellulose through an S-wrap to collapse the tube to a flat width. The lacing to form the S-wrap is accomplished without slowing the extrusion speed. At the start of the extrusion operation, the extrusion path leads between a pair of horizontally lacing members. After the leading edge of the extruded tube has passed downwardly through the space between the lacing members, the members are rotated as a unit to bring them into contact with opposite sides of the extruded tube. This collapses the and creates the S-wrap.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: November 20, 2001
    Assignee: Viskase Corporation
    Inventors: Paul Edmund DuCharme, Jr., Owen Joseph McGarel
  • 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: 6258304
    Abstract: Lyocell fibres contain elongated domains of polyester, polyamide or an olefin copolymer, the domains having an aspect ratio at least 1.5 and being aligned substantially parallel to the axis of the fibre. A process for the preparation of lyocell fibre or film by extruding a solution of cellulose in amine oxide through a spinneret or film die at elevated temperature via an air gap into an aqueous precipitation bath is characterised in that 0.1 to 60 wt % based on cellulose of a thermoplastic low-melting polymer is incorporated into the cellulose solution. A process for the preparation of a bicomponent fibre by extruding two polymers through a spinneret in side-by-side relationship at elevated temperature is characterised in that one of the polymers is a solution of cellulose in amine oxide and the other polymer is a molten thermoplastic polymer having a melting point above 25° C. but below the extrusion temperature.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: July 10, 2001
    Assignee: Tencel Limited
    Inventor: Hardev Singh Bahia
  • Patent number: 6241927
    Abstract: The invention relates to a method of producing lyocell-type cellulose fibers by processing a spinnable solution of cellulose in an aqueous tertiary amine oxide according to the dry/wet-spinning process, which method is characterized in that a solution having a content of between 0.05% and 0.70% by mass, based on the mass of the solution, of cellulose with a molecular weight of at least 5×105 is used for spinning. The method of the invention allows the use of a spinnerette having more than 10,000 spinning holes for the spinning operation, which holes are arranged in such a manner that neighboring spinning holes are spaced maximally 3 mm apart and that the linear density of the spinning holes it at least 20.
    Type: Grant
    Filed: February 3, 1999
    Date of Patent: June 5, 2001
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Eduard Mülleder, Christoph Schrempf, Hartmut Rüf, Wilhelm Feilmair
  • Patent number: RE38583
    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: May 23, 2001
    Date of Patent: September 14, 2004
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Christian Schlossnikl, Peter Gspaltl, Johann Kalleitner, Gerold Riedl, Andreas Schweigart