Subsequent Treatment Process Patents (Class 536/85)
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Publication number: 20030130500Abstract: 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: ApplicationFiled: November 25, 2002Publication date: July 10, 2003Inventors: Hartwig Schlesiger, Wolfgang Dannhorn, Jorn-Bernd Pannek, Volkhardt Muller, Frank Hohl
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Patent number: 6525192Abstract: 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: GrantFiled: May 11, 1999Date of Patent: February 25, 2003Assignee: Shin-Etu Chemical Co., Ltd.Inventors: Sakae Obara, Hiroshi Umezawa, Naosuke Maruyama, Fumie Tanno
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Patent number: 6506712Abstract: 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: GrantFiled: May 21, 2001Date of Patent: January 14, 2003Assignee: React, LLCInventor: Bruce A. Tavares
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Publication number: 20020173432Abstract: 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: ApplicationFiled: May 21, 2001Publication date: November 21, 2002Inventor: Bruce A. Tavares
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Patent number: 6320043Abstract: 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: GrantFiled: July 8, 1999Date of Patent: November 20, 2001Assignee: Wolf Walsrode AGInventors: Gunter Weber, Detmar Redeker, Bernd Klinksiek, Jürgen Hinderer, Benno Ulfik
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Publication number: 20010031861Abstract: 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: ApplicationFiled: February 20, 2001Publication date: October 18, 2001Inventors: Tadahisa Sato, Katsuyoshi Yamakawa, Hiroshi Onishi, Tadahiro Tsujimoto
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Patent number: 6294008Abstract: 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: GrantFiled: April 21, 1999Date of Patent: September 25, 2001Assignee: The Dow Chemical CompanyInventors: Colin M. Keary, Gary J. Schulz
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Publication number: 20010021387Abstract: 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: ApplicationFiled: February 15, 2001Publication date: September 13, 2001Applicant: Clariant GmbHInventors: Ralf Krammer, Reinhard Doenges, Juergen Kirchner, Horst Wurm
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Publication number: 20010007028Abstract: 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: ApplicationFiled: December 1, 1998Publication date: July 5, 2001Inventor: GARY J. SCHULZ
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Cellulose ethers containing butenyl groups and use thereof as protective colloids in polymerizations
Patent number: 6111011Abstract: 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: GrantFiled: November 19, 1998Date of Patent: August 29, 2000Assignee: Clariant GmbHInventors: Reinhard Doenges, Rudolf Ehrler, Horst Wurm -
Patent number: 6068697Abstract: 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: GrantFiled: July 14, 1998Date of Patent: May 30, 2000Assignee: Kao CorporationInventors: Hotaka Yamamuro, Takeshi Ihara, Tomohito Kitsuki, Tetsuya Miyajima, Fujio Yamato, Makoto Kohama
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Patent number: 5840882Abstract: 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: GrantFiled: August 20, 1997Date of Patent: November 24, 1998Assignee: Clariant GmbHInventors: Reinhard Doenges, Rudolf Ehrler
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Patent number: 5808052Abstract: 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: GrantFiled: June 10, 1996Date of Patent: September 15, 1998Assignee: Wolff Walsrode AGInventors: Klaus Szablikowski, Werner Lange, Jorn-Bernd Pannek, Rene Kiesewetter
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Patent number: 5719274Abstract: 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: GrantFiled: September 22, 1995Date of Patent: February 17, 1998Assignee: Hoechst AktiengesellschaftInventors: Reinhard Doenges, Diethart Reichel
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Patent number: 5583214Abstract: 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: GrantFiled: June 5, 1995Date of Patent: December 10, 1996Assignee: Union Carbide Chemicals & Plastics Technology CorporationInventor: Emmett M. Partain, III
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Patent number: 5527902Abstract: 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: GrantFiled: November 14, 1994Date of Patent: June 18, 1996Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.Inventors: Fritz Loth, Carola Fanter
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Patent number: 5519130Abstract: 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: GrantFiled: November 21, 1994Date of Patent: May 21, 1996Assignee: Zeneca LimitedInventors: David Byrom, Barbara A. Abbishaw
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Patent number: 5504201Abstract: 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: GrantFiled: March 14, 1994Date of Patent: April 2, 1996Assignee: The Dow Chemical CompanyInventors: Kenneth C. Reibert, Gregg L. Poppe, John G. Green
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Patent number: 5500124Abstract: 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: GrantFiled: December 3, 1992Date of Patent: March 19, 1996Assignee: Hoechst AGInventors: Heinz Wallisch, Reinhard Donges, Ulrich Meyer-Blumenroth
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Patent number: 5422402Abstract: 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: GrantFiled: September 23, 1992Date of Patent: June 6, 1995Assignee: Biocompatibles LimitedInventors: Roderick W. J. Bowers, Stephen A. Jones, Peter W. Straford, Michael J. Driver
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Patent number: 5360902Abstract: 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: GrantFiled: December 15, 1992Date of Patent: November 1, 1994Assignee: Wolff Walsrode AGInventors: Oke Brauer, Bernd Haase, Dieter Herzog, Lutz Riechardt, Gerd Sonnenberg, Dietrich Tegtmeier
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Patent number: 5346542Abstract: 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: GrantFiled: November 6, 1992Date of Patent: September 13, 1994Assignee: Asahi Kasei Kogyo Kabushiki KaishaInventors: Honda Yosuke, Tanabe Tsuneaki, Yaginuma Yoshihito
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Patent number: 5324717Abstract: 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: GrantFiled: November 4, 1992Date of Patent: June 28, 1994Inventors: Thomas Berglindh, Anthony de Belder
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Patent number: 5316705Abstract: 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: GrantFiled: August 27, 1992Date of Patent: May 31, 1994Assignee: Hoechst Celanese CorporationInventors: Samuel S. McNair, Jr., David M. Gault
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Patent number: 5298584Abstract: 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: GrantFiled: December 14, 1990Date of Patent: March 29, 1994Assignee: The United States of America as represented by the Secretary of AgricultureInventors: Eugene J. Blanchard, Robert M. Reinhardt
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Patent number: 5294702Abstract: This invention relates to water-soluble polymerisable 3-allyloxy-2-hydroxypropylethers of cellulose and to a process for their preparation.Type: GrantFiled: October 2, 1992Date of Patent: March 15, 1994Assignee: Wolff Walsrode AGInventors: Jorn Breckwoldt, Klaus Szablikowski
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Patent number: 5292828Abstract: 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: GrantFiled: May 29, 1992Date of Patent: March 8, 1994Assignee: Union Carbide Chemicals & Plastics Technology CorporationInventors: Richard D. Jenkins, David R. Bassett, Gregory D. Shay
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Patent number: 5290829Abstract: 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: GrantFiled: April 2, 1992Date of Patent: March 1, 1994Assignee: Aqualon CompanyInventors: John D. Angerer, Thomas G. Majewicz, Makram H. Meshreki
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Patent number: 5218107Abstract: 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: GrantFiled: December 30, 1991Date of Patent: June 8, 1993Assignee: The Dow Chemical CompanyInventor: Gary J. Schulz
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Patent number: 5008385Abstract: 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: GrantFiled: July 15, 1988Date of Patent: April 16, 1991Assignee: Akzo N.V.Inventor: Michael Diamantoglou
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Patent number: 4997935Abstract: 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: GrantFiled: February 27, 1989Date of Patent: March 5, 1991Assignee: Akzo N.V.Inventor: Michael Diamantoglou
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Patent number: 4992538Abstract: 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: GrantFiled: June 5, 1989Date of Patent: February 12, 1991Assignee: Aqualon CompanyInventor: Arjun C. Sau
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Patent number: 4985152Abstract: 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: GrantFiled: July 14, 1989Date of Patent: January 15, 1991Assignee: Hoechst AktiengesellschaftInventors: Josef Hilbig, Guenther Welt, Manfred Ziegelmayer
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Patent number: 4981960Abstract: 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: GrantFiled: February 27, 1989Date of Patent: January 1, 1991Assignee: Akzo N.V.Inventor: Michael Diamantoglou
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Patent number: 4981959Abstract: 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: GrantFiled: February 27, 1989Date of Patent: January 1, 1991Assignee: Akzo N.V.Inventor: Michael Diamantoglou
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Patent number: 4954268Abstract: 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: GrantFiled: February 3, 1989Date of Patent: September 4, 1990Inventors: Guenther Just, Willi Wuest
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Patent number: 4940785Abstract: 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: GrantFiled: October 4, 1988Date of Patent: July 10, 1990Assignee: Degussa AktiengesellschaftInventors: Reinhard Stober, Dietmar Bischoff, Michael Huss
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Patent number: 4820813Abstract: 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: GrantFiled: February 12, 1988Date of Patent: April 11, 1989Assignee: The Dow Chemical CompanyInventor: Gary J. Schulz
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Patent number: 4689408Abstract: 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: GrantFiled: July 7, 1986Date of Patent: August 25, 1987Assignee: Hercules IncorporatedInventors: Robert A. Gelman, Eleanor C. Hawkins
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Patent number: 4672113Abstract: 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: GrantFiled: August 28, 1984Date of Patent: June 9, 1987Assignee: Hoechst AktiengesellschaftInventors: Heinz Wallisch, Uth H. Felcht, Michael Kostrzewa
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Patent number: 4584370Abstract: 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: GrantFiled: August 13, 1984Date of Patent: April 22, 1986Inventors: Jun Taguchi, Hiroomi Kobayashi, Takahiro Koyama
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Patent number: 4581446Abstract: 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: GrantFiled: March 15, 1985Date of Patent: April 8, 1986Assignee: The Dow Chemical CompanyInventor: Gary J. Schulz
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Patent number: 4537958Abstract: 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: GrantFiled: June 29, 1984Date of Patent: August 27, 1985Assignee: The Dow Chemical CompanyInventors: Carl P. Strange, Harold B. Martin, Jr., Albert C. Tsang
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Patent number: 4521594Abstract: 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: GrantFiled: June 20, 1984Date of Patent: June 4, 1985Assignee: Daicel Chemical Industries, Ltd.Inventor: Tetuo Kanematu
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Patent number: 4508893Abstract: 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: GrantFiled: August 23, 1984Date of Patent: April 2, 1985Assignees: Daicel Chemical Industries Ltd., Nichirin Chemical Industries Ltd.Inventors: Takahiro Koyama, Haruo Matsumura, Teturo Morita
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Patent number: 4474950Abstract: 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: GrantFiled: August 26, 1983Date of Patent: October 2, 1984Assignee: Hoechst AktiengesellschaftInventors: Utz-Hellmuth Felcht, Helmut Berenbold
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Patent number: 4426518Abstract: 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: GrantFiled: September 10, 1982Date of Patent: January 17, 1984Assignee: Daicel Chemical Industries, Ltd.Inventor: Takeo Omiya
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Patent number: 4419490Abstract: 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: GrantFiled: June 12, 1981Date of Patent: December 6, 1983Assignee: Heyl & Co. Chemisch-Pharmazeutische FabrikInventors: Ernst Bayer, Wilhelm Schumann
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Patent number: 4404371Abstract: Cross-linked carboxymethylcellulose with intermolecular carbonate bridges.Type: GrantFiled: December 28, 1981Date of Patent: September 13, 1983Assignee: Battelle Memorial InstituteInventors: Gunter Bellmann, Celeste Cervini, Jean-Pierre Sachetto
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Patent number: 4404370Abstract: 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: GrantFiled: November 23, 1980Date of Patent: September 13, 1983Assignee: Wolff Walsrode AG and Bayer AGInventors: Claus-Rudiger Bernert, Volker Hartwig, Christian Kords, Detmar Redeker