Cupro Ammonium Cellulose Patents (Class 264/199)
  • Patent number: 8926712
    Abstract: A solvent spun bamboo fiber with a high wet modulus and a producing method thereof are disclosed. The producing method includes: activating by adding a bamboo pulp into de-ionized water, adjusting the pH value, adding cellulase and adjusting the pH value by adding alkali; squeezing by vacuum dehydration; pre-dissolving by adding an aqueous solution containing 50-88% by mass of N-methylmorpholine-N-oxide; then dissolving by putting the above pre-dissolved mixture into a dissolver, heating, vacuumizing, dehydrating, dissolving, homogenizing and defoaming; spinning by spraying through a spinneret and forming a bamboo fiber by dry-wet spinning; water washing; bleaching; oiling; and drying. The present method is simple to operate, free of industrial pollution, low energy consuming, and highly safe. The bamboo fiber produced by the present method not only keeps the natural physical and chemical properties of bamboo fiber, but also has a high wet modulus without harmful chemical residues.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: January 6, 2015
    Assignee: Shanghai Lyocell Fibre Development Co., Ltd.
    Inventors: Kun Jiang, Xiaoliang Wang, Changli Zhu, Xin Wang, Dianhai Zheng
  • Patent number: 7060211
    Abstract: The present invention provides yarn and cloths made by utilizing bamboo fiber and methods for manufacturing these yarn and cloths, thereby the bamboo fiber can be utilized by being extracted from sheaths of bamboo shoots or bamboo sheaths that generate at the root of bamboo abundantly, which have been left as they are or mostly disposed of as wastes. By fibrillating or chemically treating bamboo sheaths 10 which is a main raw material, bamboo fiber 16 mainly comprising cellulose is obtained, and then it is formed into yarn by spinning. A cloth is produced as woven or knitted fabric using the yarn.
    Type: Grant
    Filed: August 19, 2002
    Date of Patent: June 13, 2006
    Assignee: Katsuyama Technos Ltd.
    Inventor: Tomonaga Oda
  • Patent number: 5849189
    Abstract: A hollow fiber blood purifying membrane which is a hollow fiber membrane substantially composed of cellulose acetate, has a substantially non-oriented distribution of cellulose acetate polymer particles on the inner surface of the hollow fibers, has a dense layer with a thickness in the range of 30-1000 nm on both the inner and outer surface of the hollow fibers and a porous structure which is substantially uniform at the membrane wall between the two dense layers, and has an in vitro ultrafiltration rate (UFR) of 10 to 50 ml/m.sup.2 and a (in vivo UFR)/(in vitro UFR) ratio of at least 0.3, a blood plasma albumin permeation blockage of at least 90%, and an in vivo .beta..sub.2 -microglobulin (.beta..sub.2 -MG) sieving coefficient of at least 0.4, as well as a process for its production.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: December 15, 1998
    Assignee: Teijin Limited
    Inventors: Shingo Emi, Kouji Soga, Satoshi Fukuhara
  • Patent number: 5505859
    Abstract: A dialysis membrane is made of a regenerated cellulose polymer in the form of a hollow fiber with a continuous internal cavity filled essentially with a gas. The hollow fiber has a porous inner and an outer surface. The outer surface of the hollow fiber is formed by a thin skin which has fine lengthwise grooves. The inner surface of the hollow fiber is positively modified by physical and/or chemical means.The invention also includes a method for manufacturing such a dialysis membrane.
    Type: Grant
    Filed: February 17, 1994
    Date of Patent: April 9, 1996
    Assignee: Akzo NV
    Inventors: Gustav Dunweg, Hans G. Breidohr, Ulrich Baurmeister, Hans G. Tilgner, Uwe Stein
  • Patent number: 5427684
    Abstract: A dialysis membrane for hemodialysis in the form of sheet films, tubular films, or hollow fibers is composed of a polysaccharide ether. The polysaccharide ether has a structure given by the formula ##STR1## in which cell is the skeleton of the unmodified cellulose molecule or of the chitin molecule, each with no hydroxyl groups, s is equal to 3 for the unmodified cellulose molecule and 2 for the chitin molecule, and x is the degree of etherification, which is in the range from 0.001 to 0.079, and R is an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, arylalkyl, arylalkenyl, and/or arylalkynyl group with 3 to 25 carbon atoms, and/or the radical of a heterocyclic compound with 3 to 25 carbon atoms, in which the carbon chain may be interrupted by oxygen or sulfur atoms.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: June 27, 1995
    Assignee: AKZO NV
    Inventors: Michael Diamantoglou, Gustav Dunweg, Thomas Rintelen
  • Patent number: 5403485
    Abstract: A dialysis membrane in the form of a hollow fiber with a continuous internal cavity is made of cellulose acetate or a cellulose acetate derivative. The hollow fiber is made by using a gas to form the internal hollow cavity. A dialysis membrane in the form of a hollow fiber with a continuous hollow cavity may be made in a process using a spinning solution containing an organic carboxylic acid. Modification agents can be added to the solution and the solution extruded through a spinneret suitable for manufacturing hollow fibers, while an internal medium is introduced simultaneously into the internal cavity of the forming hollow fiber. The precipitation of the dialysis membrane thus formed and an ordinary further aftertreatment take place subsequently in a precipitation bath. The hollow fiber is made by using a gas as the internal medium to form the internal cavity.
    Type: Grant
    Filed: May 19, 1993
    Date of Patent: April 4, 1995
    Assignee: Akzo N.V.
    Inventors: Gustav Dunweg, Lother Steinfeld, Wolfgang Ansorge
  • Patent number: 4882106
    Abstract: A material is formed into hollow fiber form, and the surface characteristics of the interior bore is selectively modified in a predetermined fashion by a reactive lumen fluid. Nucleophilic materials, such as regenerated cellulose, can be formed into hollow fibers and simultaneously modified to improve their biocompatibility in accordance with the invention.
    Type: Grant
    Filed: March 11, 1987
    Date of Patent: November 21, 1989
    Assignee: Baxter Travenol Laboratories, Inc.
    Inventors: Richard J. Johnson, Dennis E. Chenoweth, Daniel R. Boggs, Michael J. Lysaght
  • Patent number: 4824569
    Abstract: Unstretched hollow fibers of cuprammonium cellulose for dialysis possessing a film structure having a porosity of 15 to 25%, a pore diameter of 25 to 40 .ANG., and an ultrafiltration ratio of 3.0 to 5.5 ml/ are obtained by extruding, coagulating, and regenerating a cuprammonium cellulose spinning dope having a cellulose concentration of 6.8 to 8.7% and a viscosity of 500 to 1,300 poises (at C.).
    Type: Grant
    Filed: May 26, 1987
    Date of Patent: April 25, 1989
    Assignee: Terumo Kabushiki Kaisha Trading as Terumo Corporation
    Inventors: Kazuhiko Suzuki, Kazuaki Takahara
  • Patent number: 4822540
    Abstract: A porous regenerated cellulose hollow fiber is obtained by a micro-phase-separation method. The hollow fiber is characterized in that the viscosity average molecular weight is at least 5.times.10.sup.4, each of the average pore diameter D.sub.1 on the inner wall surface of the hollow fiber and the average pore diameter D.sub.2 on the outer wall surface is 0.02 to 10 .mu.m, the in-plane porosity Pr on the outer wall surface is at least 10%, and the hollow fiber comprises a wall thickness portion having pores piercing therethrough between the inner wall surface and outer wall surface and a hollow portion extending continuously over the entire fiber length.
    Type: Grant
    Filed: May 27, 1986
    Date of Patent: April 18, 1989
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Seiichi Manabe, Michitaka Iwata, Mamoru Inoue
  • Patent number: 4535028
    Abstract: A hollow fiber of cuprammonium regenerated cellulose having an axially disposed cylindrical bore extending throughout the fiber length, said bore being filled with a gas. The hollow fiber exhibits an improved dialysis performance and ultrafiltration rate over the conventional hollow fiber. Such a hollow fiber can be produced by a process comprising (a) extruding a spinning dope through an annular orifice while simultaneously injecting a gas into the bore as it is formed, and (b) allowing the fiber extrudate to free fall in an air space and dive into a depth of from 2 to 20 mm below the surface of a coagulation bath only with a downward force gained during said free fall.
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: August 13, 1985
    Assignees: Asahi Kasei Kogyo Kabushiki Kaisha, Asahi Medical Co., Ltd.
    Inventors: Masanobu Yokogi, Yoshifumi Sugimoto, Yotsuo Ono
  • Patent number: 4444663
    Abstract: A liquid composition for the manufacture of a membrane, comprising a reaction product a cuprammonium cellulose with an ammonium or alkali metal salt of a polymer containing 10 to 70 equivalent percent of a carboxyl group and having a number-averaged molecular weight in the range of from 500 to 200,000, and a membrane is obtained by molding the composition in the form of a film, immersing the shaped article thus obtained in a dilute sulfuric acid solution thereby coagulating and regenerating it, subsequently immersing the shaped article in an strong alkali solution thereby expelling said ammonium or alkali metal salt of the polymer therefrom and forming therein fine pores substantially corresponding to the molecular weight of said salt.
    Type: Grant
    Filed: September 14, 1981
    Date of Patent: April 24, 1984
    Assignee: Terumo Corporation
    Inventors: Juuro Aoyagi, Kazuhiko Suzuki, Kazuaki Takahara
  • Patent number: 4444716
    Abstract: A method for the manufacture of a hollow fiber which comprises extruding a cellulosic spinning dope through an annular spinning nozzle directly into a non-coagulative liquid layer in a bath filled in the upper layer with a coagulative liquid relative to said spinning dope and in the lower layer with a non-coagulative liquid of a halogenated hydrocarbon and, at the same time, introducing a non-coagulative liquid relative to said spinning dope into the inner center of the tubularly extruded thread of spinning dope, and subsequently passing the resultant tubular fiber of spinning dope through said coagulative liquid thereby coagulating and regenerating the fiber.
    Type: Grant
    Filed: May 25, 1982
    Date of Patent: April 24, 1984
    Assignee: Terumo Kabushiki Kaisha
    Inventors: Juuro Aoyagi, Kazuaki Takahara, Yukio Seita
  • Patent number: 4332752
    Abstract: Dialysis membranes are described in which two or more hollow fibers of cellulose regenerated from cuoxam solution are spun together and connected to each other parallel to the fiber axis. The connection may be in the form of crosspieces, which should be between about 1 and 3 times the thickness of the hollow fiber walls. A novel process for preparation of the dialysis membrane hollow fibers is also disclosed.
    Type: Grant
    Filed: October 1, 1979
    Date of Patent: June 1, 1982
    Assignee: Akzo N.V.
    Inventors: Werner Henne, Werner Bandel, Gustav Dunweg
  • Patent number: 4164437
    Abstract: A dialyzing membrane, especially for hemodialysis, formed as a hollow fiber, tubular foil or flat sheet by regeneration of cellulose from a cuprammonium solution, the membrane comprising at least two firmly adhered cellulosic layers including at least one dialyzing layer consisting essentially of a semipermeable regenerated cellulose and at least one adsorbent layer consisting of said regenerated cellulose containing embedded therein fine particles of an adsorbent material in an amount of up to 95% by weight with reference to the dry weight of the adsorbent layer, preferably 1 to 90% and especially 20 to 70% by weight, when the adsorbent layer is part of a hollow fiber structure.
    Type: Grant
    Filed: June 23, 1977
    Date of Patent: August 14, 1979
    Assignee: Akzo N.V.
    Inventors: Werner Henne, Gustav Dunweg, Werner Schmitz, Raimund Pohle, Friedrich Lawitzki
  • Patent number: RE32277
    Abstract: An improved dialyzing hollow fiber of cuprammonium regenerated cellulose, showing a substantially similar network structure of fine gap passage routes having a max. gap size of 200 A when .[.seen.]. .Iadd.observed .[.its.]. any cross-section and .[.logitudinal.]. .Iadd.longitudinal .Iaddend.section, having skinless structure at its inside and outside surface of the hollow fiber and representing a superior water permeability.
    Type: Grant
    Filed: January 31, 1985
    Date of Patent: November 4, 1986
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Masami Tsuge, Shinichi Uematsu, Yotsuo Ono, Shokichi Eiga, Minoru Makita