Subsequent Treatment Process Patents (Class 536/85)
  • Publication number: 20030130500
    Abstract: A process for preparing cellulose ethers having delayed dissolution in water is described. The process comprises: (a) treating a moist cellulose ether with a solution comprising a dialdehyde; (b) adding an aqueous salt solution to the moist cellulose ether, such that said cellulose ether has a pH of from 6.0 to 8.0, the aqueous salt addition being performed at least one of, (i) prior to step (a), (ii) concurrently with step (a), and (iii) subsequent to step (a); and (c) drying and comminuting the treated cellulose ether of step (b). The cellulose ether, or mixtures of cellulose ethers, prepared by the method of the present invention may be used as protective colloids, thickeners and adhesives.
    Type: Application
    Filed: November 25, 2002
    Publication date: July 10, 2003
    Inventors: Hartwig Schlesiger, Wolfgang Dannhorn, Jorn-Bernd Pannek, Volkhardt Muller, Frank Hohl
  • Patent number: 6525192
    Abstract: The present invention provides a low-substituted hydroxypropyl cellulose having a loose bulk density of not less than 0.40 g/mL and a tap bulk density of not less than 0.60 g/mL and a process for producing the same.
    Type: Grant
    Filed: May 11, 1999
    Date of Patent: February 25, 2003
    Assignee: Shin-Etu Chemical Co., Ltd.
    Inventors: Sakae Obara, Hiroshi Umezawa, Naosuke Maruyama, Fumie Tanno
  • Patent number: 6506712
    Abstract: Additives useful for reducing the coefficient of friction in lubricants, greases, or cosmetic formulations, and useful as a substitute for talc and as an anti-misting material are obtained by subjecting a raw plant material, such as cotton, to a dosage of radiation from an electron beam source. The irradiated plant material is subsequently fragmented, or micronized, to product the friction-reducing additive with a reduced diameter capable of reducing the coefficient of friction, used for anti-misting or as a substitute for talc in a variety of applications.
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: January 14, 2003
    Assignee: React, LLC
    Inventor: Bruce A. Tavares
  • Publication number: 20020173432
    Abstract: Additives usefull for reducing the coefficient of friction in lubricants, greases, or cosmetic formulations, and useful as a substitute for talc and as an anti-misting material are obtained by subjecting a raw plant material, such as cotton, to a dosage of radiation from an electron beam source. The irradiated plant material is subsequently fragmented, or micronized, to product the friction-reducing additive with a reduced diameter capable of reducing the coefficient of friction, used for anti-misting or as a substitute for talc in a variety of applications.
    Type: Application
    Filed: May 21, 2001
    Publication date: November 21, 2002
    Inventor: Bruce A. Tavares
  • Patent number: 6320043
    Abstract: The invention relates to a new, particularly economic process for preparing pulverulent polysaccharide derivatives, in particular cellulose derivatives, having a thermal flocculation point; the process comprises soaking or dissolving the polysaccharide derivative in a solvent or mixed solvent, dividing/comminuting the soaked or dissolved polysaccharide derivative by thermal and/or mechanical liquid separation and an optional drying step.
    Type: Grant
    Filed: July 8, 1999
    Date of Patent: November 20, 2001
    Assignee: Wolf Walsrode AG
    Inventors: Gunter Weber, Detmar Redeker, Bernd Klinksiek, Jürgen Hinderer, Benno Ulfik
  • Publication number: 20010031861
    Abstract: A method of making cellulose polymer solution comprises dissolving a cellulose polymer raw material in a chlorine-free organic solvent system under a high temperature and a high pressure condition belonging to the nearcritical or the supercritical region of the system. By removing the solvent from the thus obtained cellulose polymer solution, cellulose polymer powders are also produced.
    Type: Application
    Filed: February 20, 2001
    Publication date: October 18, 2001
    Inventors: Tadahisa Sato, Katsuyoshi Yamakawa, Hiroshi Onishi, Tadahiro Tsujimoto
  • Patent number: 6294008
    Abstract: Disclosed is a cellulose ether composition having a low molecular weight cellulose ether of a viscosity of about 200 centipoise or less in a two percent aqueous solution at 20° C. The composition has a sodium chloride content of about 0.3 weight percent or less based upon the weight of the cellulose ether. The composition exhibits significantly reduced haze formation when in capsule form. Also disclosed is a process for making the composition.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: September 25, 2001
    Assignee: The Dow Chemical Company
    Inventors: Colin M. Keary, Gary J. Schulz
  • Publication number: 20010021387
    Abstract: The present invention relates to water-soluble, organosilylated cellulose ethers in which the organosilyl groups are attached hydrolysis-stably to the cellulose ethers and the remaining substituents on the silicon atoms of the organosilyl groups are likewise stable to hydrolysis. The cellulose ethers of the invention exhibit a strongly thickening action in aqueous solution, even at very low degrees of silylation, and are suitable as thickeners, for example, in paints, adhesives, and cosmetics. They are further suitable as protective colloids in the preparation of polymer dispersions.
    Type: Application
    Filed: February 15, 2001
    Publication date: September 13, 2001
    Applicant: Clariant GmbH
    Inventors: Ralf Krammer, Reinhard Doenges, Juergen Kirchner, Horst Wurm
  • Publication number: 20010007028
    Abstract: There is a process for making a cellulose ether. The process comprises the following: a) alkalyzing a cellulose pulp; b) etherifying the alkalyzed cellulose pulp to form a cellulose ether; c) washing the cellulose ether; d) drying the cellulose ether; e) milling the cellulose ether to a particulate form; f) heating the particulate cellulose ether; g) tumbling the particulate cellulose ether while simultaneously contacting it with an acid to partially depolymerize it to a lower molecular weight; h) partially or substantially neutralizing the acid. There is also an apparatus for making the cellulose ether.
    Type: Application
    Filed: December 1, 1998
    Publication date: July 5, 2001
    Inventor: GARY J. SCHULZ
  • Patent number: 6111011
    Abstract: Water-soluble, nonionic cellulose ethers selected from the group consisting of alkylcelluloses and hydroxyalkylcelluloses which are additionally substituted by butenyl groups are used as protective colloids in the preparation of aqueous polymer dispersions.
    Type: Grant
    Filed: November 19, 1998
    Date of Patent: August 29, 2000
    Assignee: Clariant GmbH
    Inventors: Reinhard Doenges, Rudolf Ehrler, Horst Wurm
  • Patent number: 6068697
    Abstract: A polysaccharide derivative prepared by replacing all or part of the hydroxyl hydrogen atoms of a polysaccharide or polysaccharide derivative by (A) a hydrophobic substituent having a C.sub.8 -C.sub.43 hydrocarbon chain as the partial structure and (B) an ionic hydrophilic substituent having at least one member selected from the group consisting of sulfonic, carboxyl phosphoric, and sulfate groups and salts thereof as the partial structure, wherein the average degree of replacement by the substituent (A) is 0.0001 or above but below 0.001 per constituent monosaccharide residue as determined by Zeisel's method or the diazomethane method and that by the substituent (B) is 0.01 to 2.0 per constituent monosaccharide residue as determined by colloidal titration. This polysaccharide derivative is useful as the admixture for hydraulic materials and can give stable hydraulic compositions excellent in dispersion.
    Type: Grant
    Filed: July 14, 1998
    Date of Patent: May 30, 2000
    Assignee: Kao Corporation
    Inventors: Hotaka Yamamuro, Takeshi Ihara, Tomohito Kitsuki, Tetsuya Miyajima, Fujio Yamato, Makoto Kohama
  • Patent number: 5840882
    Abstract: Cellulose ethers which contain hydroxyalkyl groups are prepared, with the recovery of sodium hydroxide, by cellulose being etherified with alkylene oxide in a water-containing organic suspension medium in the presence of at least 1.0 mol of sodium hydroxide per mole of anhydroglucose units, the water-containing organic suspension medium being separated off after the etherification reaction is complete, the crude cellulose ether being extracted with a suitable solvent mixture, the lower-boiling organic components being distilled off from the solvent mixture after the extraction, the water-containing organic suspension medium separated off being added to the distillation residue of the solvent mixture to form a multiphase mixture, the bottom phase of the multiphase mixture being separated and the sodium hydroxide present in the bottom phase being reused.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: November 24, 1998
    Assignee: Clariant GmbH
    Inventors: Reinhard Doenges, Rudolf Ehrler
  • Patent number: 5808052
    Abstract: The present invention relates to water-soluble, particularly ternary, preferably ionic, cellulose mixed ethers, more particularly to anionic water-soluble cellulose mixed ethers, as additives for drilling fluid applications.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: September 15, 1998
    Assignee: Wolff Walsrode AG
    Inventors: Klaus Szablikowski, Werner Lange, Jorn-Bernd Pannek, Rene Kiesewetter
  • Patent number: 5719274
    Abstract: Low molecular weight cellulose ethers which are suitable as a coating material for solid metered units and as an additive in ceramic compositions or cosmetics formulations or as a polymerization auxiliary are obtained by irradiation of a mixture of a higher molecular weight cellulose ether and a base with electrons.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: February 17, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Reinhard Doenges, Diethart Reichel
  • Patent number: 5583214
    Abstract: Cellulose ether derivatives comprising a hydrophobic substituent having an unsaturated alkyl portion are disclosed. The unsaturation in the alkyl portion of the hydrophobic substituent can promote crosslinking of the cellulose ether derivative. The cellulose ether derivatives are useful as ingredients in latex compositions. The cellulose ether derivatives can provide associative thickening and rheological properties to latex composition during storage and application. In addition, after the latex composition is applied to the surface to be coated, the cellulose ethers of the present invention can promote crosslinking of the latex film to provide a hard and durable coating. Latex paint compositions comprising the cellulose ether derivatives of the present invention are also disclosed.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: December 10, 1996
    Assignee: Union Carbide Chemicals & Plastics Technology Corporation
    Inventor: Emmett M. Partain, III
  • Patent number: 5527902
    Abstract: Bead-shaped cellulose products and a process for the manufacturing of such ead-shaped porous cellulose products provide improved characteristics, particularly a hydrophilic, reversibly expandable cellulose matrix with a pore structure that can be adjusted within wide ranges in a targeted manner while non-specific mutual reactions are simultaneously suppressed by biomacromolecules.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: June 18, 1996
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Fritz Loth, Carola Fanter
  • Patent number: 5519130
    Abstract: Haloalkanoic acid impurities are decomposed in the presence of certain surfactants carboxymethyl cellulose or thioglycollic acids salts which may contain them as unconverted reactants by contacting them with dehalogenase enzyme.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: May 21, 1996
    Assignee: Zeneca Limited
    Inventors: David Byrom, Barbara A. Abbishaw
  • Patent number: 5504201
    Abstract: A process for recovering salable cellulose ether solids in an aqueous slurry from a reactor wherein such cellulose ether solids are produced, or in an aqueous slurry from a centrifuge or filter wherein a portion of the cellulose ether solids from the reactor have been removed, comprising flowing the slurry into a hydraulic cyclone at a temperature above the gel point of the cellulose ether solids in such slurry and under conditions which are tailored to the particular cellulose ether solids in the slurry and to the process by which these have been made.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: April 2, 1996
    Assignee: The Dow Chemical Company
    Inventors: Kenneth C. Reibert, Gregg L. Poppe, John G. Green
  • Patent number: 5500124
    Abstract: The invention relates to a process for the purifying working-up of liquid reaction media and/or wash media obtained during preparation of cellulose ethers, which are insoluble in hot water, from cellulose, an alkali metal hydroxide and at least one etherifying agent in a medium containing water and if appropriate at least one organic solvent, by ultrafiltration of the media into a permeate and concentrate, which comprises carrying out the ultrafiltration of the reaction media and/or wash media at a temperature at or above the flocculation temperature of the cellulose ethers.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: March 19, 1996
    Assignee: Hoechst AG
    Inventors: Heinz Wallisch, Reinhard Donges, Ulrich Meyer-Blumenroth
  • Patent number: 5422402
    Abstract: A process of treating suitable synthetic polymers comprising the steps of (a) where appropriate, activating the surface to be treated, and, if necessary, providing spacer groups thereon; and (b) treating the surface with a compound of Formula (I), ##STR1## wherein Y' is an alkylene group optionally containing an aryl group, a poly(ethylene glycol) or a glycerol group; R may be the same or different and each is a straight or branched C.sub.1-4 alkyl group, n is from 1 to 4 and X is a group which reacts with functional groups of the polymer. Polymeric surfaces and materials thus produced and shaped articles containing such surfaces and materials.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: June 6, 1995
    Assignee: Biocompatibles Limited
    Inventors: Roderick W. J. Bowers, Stephen A. Jones, Peter W. Straford, Michael J. Driver
  • Patent number: 5360902
    Abstract: The present invention relates to a process for producing methyl hydroxyalkyl cellulose ethers by alkalisation and etherification of celluloses, rinsing the methyl hydroxyalkyl cellulose ethers with water at higher temperatures and recovering the short-chain cellulose ethers that are soluble in the wash water, wherein the wash water containing sodium chloride and organic by-products is passed across a first stage of a membrane filtration having a molecular cut size of 200 to 150,000 Dalton, is concentrated during this process and passes across a second stage of a membrane filtration.
    Type: Grant
    Filed: December 15, 1992
    Date of Patent: November 1, 1994
    Assignee: Wolff Walsrode AG
    Inventors: Oke Brauer, Bernd Haase, Dieter Herzog, Lutz Riechardt, Gerd Sonnenberg, Dietrich Tegtmeier
  • Patent number: 5346542
    Abstract: A novel polymer aqueous dispersion of enteric cellulose derivatives without ester bonded substituents, of which anionic functional groups form salts with cations. The aqueous dispersion of the present invention is used as coating agents for foods and pharmaceuticals. It has high dispersion stability such as high mechanical stability and high storage stability.
    Type: Grant
    Filed: November 6, 1992
    Date of Patent: September 13, 1994
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Honda Yosuke, Tanabe Tsuneaki, Yaginuma Yoshihito
  • Patent number: 5324717
    Abstract: A therapeutical composition comprising hydrolyzed carboxyalkyl cellulose, wherein alkyl is methyl, ethyl or propyl, optionally in salt form, which hydrolyzed carboxyalkyl cellulose has a mass average molecular mass from about 200 to about 10,000. A method for providing a laxative effect comprises the administration of such a composition.
    Type: Grant
    Filed: November 4, 1992
    Date of Patent: June 28, 1994
    Inventors: Thomas Berglindh, Anthony de Belder
  • Patent number: 5316705
    Abstract: An improved process for the production of cellulose ester fibrets wherein a thickened slurry of the fibrets in a liquid mixture of a solvent for the fibrets and a fibret non-solvent is contacted with saturated steam in the separation of the solvent from the fibrets.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: May 31, 1994
    Assignee: Hoechst Celanese Corporation
    Inventors: Samuel S. McNair, Jr., David M. Gault
  • Patent number: 5298584
    Abstract: Anionically dyeable smooth-dry crosslinked cellulose is produced by modifying cellulose-containing material with the combination of a hydroxyalkylamine or a hydroxyalkyl quaternary ammonium salt, one or more glycols, and a crosslinking agent. The reaction is typically catalyzed with salts such as zinc nitrate or magnesium chloride used either alone or in conjunction with citric acid. Types of usable anionic dyes include acid, direct, and reactive dyes. The cellulose-containing material may be in the form of fibers, threads, linters, roving, fabrics, yarns, slivers and paper.
    Type: Grant
    Filed: December 14, 1990
    Date of Patent: March 29, 1994
    Assignee: The United States of America as represented by the Secretary of Agriculture
    Inventors: Eugene J. Blanchard, Robert M. Reinhardt
  • Patent number: 5294702
    Abstract: This invention relates to water-soluble polymerisable 3-allyloxy-2-hydroxypropylethers of cellulose and to a process for their preparation.
    Type: Grant
    Filed: October 2, 1992
    Date of Patent: March 15, 1994
    Assignee: Wolff Walsrode AG
    Inventors: Jorn Breckwoldt, Klaus Szablikowski
  • Patent number: 5292828
    Abstract: Water-soluble polymers are disclosed which comprise hydrophobic segments, each segment containing at least one hydrophobic group or comlex hydrophobic group covalently bonded to the polymer, wherein the polymer has an amount of complex hydrophobic groups sufficient to provide for enhanced thickening of aqueous solutions containing the polymer. These polymers provide superior thickening and leveling in aqueous systems through hydrophobic associations, and aid suspension of particulate materials in non-aqueous systems.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: March 8, 1994
    Assignee: Union Carbide Chemicals & Plastics Technology Corporation
    Inventors: Richard D. Jenkins, David R. Bassett, Gregory D. Shay
  • Patent number: 5290829
    Abstract: A purified hydroxyethylcellulose (HEC) or hydroxypropylcellulose (HPC) reacts with a perfluorinated alkyl glycidyl ether to produce an associative thickener wherein a fluorinated C.sub.8 chain is nearly as effective as a hydrocarbyl C.sub.16 straight chain hydrophobe. A preferred glycidyl ether is prepared by reacting a terminal hydroxyl of a perfluorinated surfactant with epichlorohydrin.
    Type: Grant
    Filed: April 2, 1992
    Date of Patent: March 1, 1994
    Assignee: Aqualon Company
    Inventors: John D. Angerer, Thomas G. Majewicz, Makram H. Meshreki
  • Patent number: 5218107
    Abstract: This invention is a process of removing water-soluble impurities from a water-soluble cellulose ether aqueous solution containing such water-soluble impurities comprising treating an aqueous solution comprising a water-soluble cellulose ether and a water-soluble impurity by means of ultrafiltration and diafiltration at conditions effective to produce a treated aqueous solution having a reduced concentration of the water-soluble impurity and an increased concentration of the water-soluble cellulose ether.
    Type: Grant
    Filed: December 30, 1991
    Date of Patent: June 8, 1993
    Assignee: The Dow Chemical Company
    Inventor: Gary J. Schulz
  • Patent number: 5008385
    Abstract: Cellulose derivatives are disclosed which have the following formula: ##STR1## wherein Z is selected from the group consisting of alkylene, alkenylene, alkynylene, cycloalkylene or benzylene or xylylene radicals, which may or may not be substituted;X is selected from the group consisting of --H, --NR.sub.2, --N.sup.+ R.sub.3, --CN, --COOH, --SO.sub.3 H, --SO.sub.3 H, --PO(OR).sub.2, CONR.sub.2 or --Si(OR).sub.3 ;R is selected from the group consisting of hydrogen, alkyl and alkenyl groups having from 1 to 25 carbon atoms, and cycloalkyl, tolyl and phenyl groups;Y is selected from the group consisting of alkyl, alkenyl, alkynyl groups having from 1 to 36 carbon atoms, which may or may not be substituted, cycloalkyl, phenyl, tolyl and benzyl groups, ##STR2## (--CH.dbd.CH--COOH), and NHR, where R has the same meaning as in X, andm=0 to 2.5n=0.01 to 2.95,with the provision that, when m=0, n.gtoreq.1.55, if Y is an alkyl radical with 1 to 5 carbon atoms, 3-(CH.sub.2).sub.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: April 16, 1991
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 4997935
    Abstract: A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R" is H or R, R"' denotes R, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and r=0 to 1. A process for preparation of the cellulose derivatives is also disclosed.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: March 5, 1991
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 4992538
    Abstract: Silated polysaccharides having 0.0005 to 2.0 silyl molar substitution per anhydrosaccharide unit form water resistant films when cast from aqueous solution and dried in the presence of atmospheric carbon dioxide. These films are soluble in aqueous caustic. A preferred water soluble polymer is a cellulose ether with 0.005 to 1.0 silyl substitution.
    Type: Grant
    Filed: June 5, 1989
    Date of Patent: February 12, 1991
    Assignee: Aqualon Company
    Inventor: Arjun C. Sau
  • Patent number: 4985152
    Abstract: The present invention relates to a process and a device for selectively separating the solvents employed in the preparation and purification of products. In this connection the different solvents are removed from the product to be treated by means of mechanical separation and subsequent admission of steam, and are collected separately. As a result of this, mixing of solvents from the preparation and from the purification is avoided, so that the working up of a solvent mixture is superfluous. The proces and the device are preferably used in the process for producing starch ethers and cellulose ethers.
    Type: Grant
    Filed: July 14, 1989
    Date of Patent: January 15, 1991
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Josef Hilbig, Guenther Welt, Manfred Ziegelmayer
  • Patent number: 4981960
    Abstract: A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein Cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R" is H or R, Z corresponds to the following groups of atoms: SR", SO.sub.3 H and salts thereof, SO-R, SONR".sub.2, SO.sub.2 -R, SO.sub.2 NR".sub.2, SO.sub.2 H and salts thereof, F, Cl, Br, I, NR".sub.2, PR".sub.2, PO.sub.3 H.sub.2 and salts thereof, PO.sub.2 H(OR), PO(OR).sub.2, PO.sub.2 HR" and salts thereof, POR"(OR) and POR".sub.2, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and z=0.01 to 0.45. A process for preparation of the cellulose derivatives is also disclosed.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: January 1, 1991
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 4981959
    Abstract: A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is unmodified cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, m=0.75 to 2.85, and x=0.005 to 2.10. A process for preparation of the cellulose derivatives is also disclosed.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: January 1, 1991
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 4954268
    Abstract: A process is disclosed for recovering a cellulose ether from a cellulose ether suspension in which the cellulose ether is recovered as a filter cake from a pressure filtration, particularly using a rotary pressure filter. Clogging of the separation or filtration device is avoided, providing for a long useful life. A multi-layer wire mesh filter medium is employed, formed of mesh layers of different wire thicknesses and/or mesh size. After removal of the filter cake, the filter medium is cleaned with steam, compressed air or pressurized water.
    Type: Grant
    Filed: February 3, 1989
    Date of Patent: September 4, 1990
    Inventors: Guenther Just, Willi Wuest
  • Patent number: 4940785
    Abstract: A method for preparing cellulose ethers containing tertiary or quaternary nitrogen by reacting alkylene epoxides with cellulose or its derivatives in an alkaline medium in the presence of water. Alkylene epoxides of the formulas ##STR1## or mixtures thereof, in which n=1, 2 or 3, R.sup.1, R.sup.2 and R.sup.3 correspond to the same or different alkyl groups with 1 to 18 carbon atoms or R.sup.1 corresponds to the benzyl group or --C.sub.2 H.sub.4 OH and X is chloride, bromide, sulfate or acetate are used as cationization agents.
    Type: Grant
    Filed: October 4, 1988
    Date of Patent: July 10, 1990
    Assignee: Degussa Aktiengesellschaft
    Inventors: Reinhard Stober, Dietmar Bischoff, Michael Huss
  • Patent number: 4820813
    Abstract: High viscosity cellulose ether products are produced by grinding a substantially dry high molecular weight cellulose ether under conditions of mild mechanical impact such as those encountered in a high speed air swept impact mill. It has been found that such a cellulose ether product has several times the intrinsic viscosity of a product of substantially equivalent particle size by ball mill or hammer mill grinding.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: April 11, 1989
    Assignee: The Dow Chemical Company
    Inventor: Gary J. Schulz
  • Patent number: 4689408
    Abstract: Disclosed are novel sodium salt of carboxymethylcellulose (CMC) which are substantially nonfibrous, have a degree of substitution (D.S.) of 0.2 to 0.9 and an absorbency of at least 25 g. liquid/g. the novel CMC material, and are prepared from a cellulose furnish having a degree of polymerization (D.P.) of greater than 1,000; and to processes for preparing same. Owing to their high absorbency properties, they are particularly useful in the manufacture of disposable nonwoven products, such as adult incontinence pads, feminine hygiene products, disposable diapers and surgical dressings.
    Type: Grant
    Filed: July 7, 1986
    Date of Patent: August 25, 1987
    Assignee: Hercules Incorporated
    Inventors: Robert A. Gelman, Eleanor C. Hawkins
  • Patent number: 4672113
    Abstract: Disclosed is a process for the purification treatment of liquid reaction and/or washing media obtained in the preparation of cellulose ethers which comprises distilling and subsequently ultrafiltering the media. In the distilling step, the low-boiling organic by-products of the reaction, the residual, non-reacted, low-boiling organic reaction components and/or the optionally used organic solvents are separated in the form of a distillate. The aqueous distillation residue, which particularly comprises salts, a cellulose constituent and possibly medium and/or high-boiling organic by-products of the reaction and/or non-reacted organic reaction components, is thereafter subjected to ultrafiltration. Ultrafiltration results in a permeate, in which the COD values are, for example, reduced by about 20% by weight.
    Type: Grant
    Filed: August 28, 1984
    Date of Patent: June 9, 1987
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Heinz Wallisch, Uth H. Felcht, Michael Kostrzewa
  • Patent number: 4584370
    Abstract: The present invention is directed to a method of producing calcium cellulose glycolate. Basically, the method comprises converting sodium cellulose glycolate to calcium cellulose glycolate in a heterogeneous reaction system under particular reaction conditions.
    Type: Grant
    Filed: August 13, 1984
    Date of Patent: April 22, 1986
    Inventors: Jun Taguchi, Hiroomi Kobayashi, Takahiro Koyama
  • Patent number: 4581446
    Abstract: Impurities in cellulose ether compositions are removed by providing a functionally effective thickness of a cellulose ether composition to a filtration device, and contacting the thickness, in a manner such that substantial thickness is maintained with at least one extracting solution in which the impurities in the cellulose ether are soluble such that a gradient impurity concentration is formed. High purity cellulose ethers are prepared, without experiencing large product losses.
    Type: Grant
    Filed: March 15, 1985
    Date of Patent: April 8, 1986
    Assignee: The Dow Chemical Company
    Inventor: Gary J. Schulz
  • Patent number: 4537958
    Abstract: Non-gelling cellulose ethers are purified by mixing same with a dialdehyde under acidic conditions and under high agitation, forming a slurry of the treated cellulose ether, rapidly transferring the slurry to a filter and then dewatering said slurry.
    Type: Grant
    Filed: June 29, 1984
    Date of Patent: August 27, 1985
    Assignee: The Dow Chemical Company
    Inventors: Carl P. Strange, Harold B. Martin, Jr., Albert C. Tsang
  • Patent number: 4521594
    Abstract: A process for producing sodium carboxymethylcellulose having an excellent dispersibility in water by heat-treating sodium carboxymethylcellulose to crosslink the same. The starting sodium carboxymethylcellulose has an equivalent ratio of the free carboxylic acid group to the sodium carboxylate of at least 0.01 to 100 and a viscosity of at least 100 cP (as a 1% aqueous solution).
    Type: Grant
    Filed: June 20, 1984
    Date of Patent: June 4, 1985
    Assignee: Daicel Chemical Industries, Ltd.
    Inventor: Tetuo Kanematu
  • Patent number: 4508893
    Abstract: A process for the preparation of a powdery calcium cellulose glycolate which comprises reacting cellulose glycolic acid in wet form with a calcium reagent, drying and pulverizing the resultant, wherein the calcium reagent is calcium hydroxide or a combination of calcium hydroxide and calcium carbonate.
    Type: Grant
    Filed: August 23, 1984
    Date of Patent: April 2, 1985
    Assignees: Daicel Chemical Industries Ltd., Nichirin Chemical Industries Ltd.
    Inventors: Takahiro Koyama, Haruo Matsumura, Teturo Morita
  • Patent number: 4474950
    Abstract: Modified cellulose reaction products, which are dispersible in aqueous media over a broad pH range without lump formation, are prepared by reacting water-soluble cellulose ether with a specified silane modifying agent in the amount of from 0.0001 to 0.12 mole of modifying agent per mole of cellulose in the cellulose ether.
    Type: Grant
    Filed: August 26, 1983
    Date of Patent: October 2, 1984
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Utz-Hellmuth Felcht, Helmut Berenbold
  • Patent number: 4426518
    Abstract: A process is disclosed for the preparation of an alkali salt of a carboxymethylcellulose ether by reacting a cellulosic material with an etherifying agent, in the presence of an alkali, in an aqueous organic solvent, wherein the improvement comprises adding the etherifying agent and only part of the entire amount of said alkali in the initial stage of the reaction, thereby initiating the etherification reaction in the presence of an excess amount of the etherifying agent such that the molar ratio of ##EQU1## is in the range of 0.10 to 0.99; and subsequently adding the remainder of said alkali in one or more portions in a second stage and carrying out the etherification reaction in such a manner that said molar ratio of alkali etherifying agent in the final stage becomes at least 1.00.
    Type: Grant
    Filed: September 10, 1982
    Date of Patent: January 17, 1984
    Assignee: Daicel Chemical Industries, Ltd.
    Inventor: Takeo Omiya
  • Patent number: 4419490
    Abstract: The invention relates to polymeric soluble hydrogenation catalysts in which a metal of the eighth subgroup of the periodic system is bound by covalent and/or secondary valent bond to a soluble polymer. The hydrogenation catalysts are produced by reacting the selected polymer having a functional group with a metal, metal complex or metal salt wherein the metal is of the eighth subgroup of the periodic table, the reaction taking place in aqueous solution or in solution in an organic solvent. The catalysts of the invention can be used for the catalytic hydrogenation of organic compounds in solution.
    Type: Grant
    Filed: June 12, 1981
    Date of Patent: December 6, 1983
    Assignee: Heyl & Co. Chemisch-Pharmazeutische Fabrik
    Inventors: Ernst Bayer, Wilhelm Schumann
  • Patent number: 4404371
    Abstract: Cross-linked carboxymethylcellulose with intermolecular carbonate bridges.
    Type: Grant
    Filed: December 28, 1981
    Date of Patent: September 13, 1983
    Assignee: Battelle Memorial Institute
    Inventors: Gunter Bellmann, Celeste Cervini, Jean-Pierre Sachetto
  • Patent number: 4404370
    Abstract: A process for the purification and isolation of cellulose or starch ethers wherein directly after the etherification step the suspension agent and the extraction of the ether product with the purifying agent is carried out on the same continuously working filter.
    Type: Grant
    Filed: November 23, 1980
    Date of Patent: September 13, 1983
    Assignee: Wolff Walsrode AG and Bayer AG
    Inventors: Claus-Rudiger Bernert, Volker Hartwig, Christian Kords, Detmar Redeker