Hydroxyethyl Patents (Class 536/96)
  • Patent number: 5589589
    Abstract: A process and apparatus for screening cellulose ethers which have a finely fibrous or wad-like or woolly structure, wherein the process comprises the following steps:a) applying the cellulose ether (material to be screened) to a sieve surface,b) dividing the material to be screened into an screenable portion (acceptable size material or material passing through the sieve) and a circulating portion (oversize material or sieve surface tailings) with the aid of an agitated (preferably vibrating and/or tumbling) sieve surface,c) flushing through the agitated sieve surface from below, generally perpendicularly to the sieve surface, with an air flow,d) discharging (recovering) the acceptable size material, ande) discharging the circulating portion from the sieving system.The air flow inhibits clogging or plugging of or matting upon the sieve surface and is preferably directed upward by slit nozzles arranged below the sieve surface.
    Type: Grant
    Filed: April 11, 1995
    Date of Patent: December 31, 1996
    Assignee: Hoechst AG
    Inventors: Manfred Sponheimer, Guenther Welt, Manfred Ziegelmayer
  • Patent number: 5463037
    Abstract: A process for producing a mixed cellulose ether comprising reacting a starting cellulose ether with an etherifying agent is disclosed, wherein said starting cellulose ether comprises at least 18 mol % of a 6-substituted glucose unit and at least 15 mol % of an unsubstituted glucose unit. A high utilization of the etherfifying agent can be reached. The resulting mixed cellulose ether has a high solubility in water and an aqueous solution of the resulting mixed cellulose ether has excellent properties such as flow properties and clarity.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: October 31, 1995
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Atsunobu Kiyose, Yonosuke Kato
  • Patent number: 5426182
    Abstract: Polysaccharides, including hydroxyethyl cellulose, having complex hydrophobic group substitution, provide latex compositions, such as paints, with improved rheology and stability. Improved processes for producing such polysaccharides are also provided.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: June 20, 1995
    Assignee: Union Carbide Chemical & Plastics Technology Corporation
    Inventors: Richard D. Jenkins, David R. Bassett, Gregory D. Shay
  • Patent number: 5385607
    Abstract: The invention relates to a new class of water-soluble ionic cellulose derivatives and their use as additive for gypsum- and cement-containing compounds.
    Type: Grant
    Filed: January 27, 1993
    Date of Patent: January 31, 1995
    Assignee: Wolff Walsrode AG
    Inventors: Rene Kiesewetter, Klaus Szablikowski, Werner Lange
  • Patent number: 5358561
    Abstract: The invention relates to water-soluble ionic cellulose derivatives and their use as additives for gypsum- and cement-containing compounds.
    Type: Grant
    Filed: January 27, 1993
    Date of Patent: October 25, 1994
    Assignee: Wolff Warlsrode AG
    Inventors: Rene Kiesewetter, Klaus Szablikowski, Werner Lange
  • 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: 5278203
    Abstract: Water-soluble, polymer viscosifiers of aqueous solutions, also known as gelling agents, can be suspended in a hydrocarbon carrier fluid, such as, diesel to prepare a liquid gel concentrate. When a liquid gel concentrate is added to an aqueous solution the gelling agent disperses into it and viscosifies it. To make an improved performance admixture for preparation of liquid gel concentrates and render the gelling agent suspendable in the hydrocarbon carrier fluid, it is first coated with a mixture of an oil-compatible polymer suspending agent, such as a polymer suspension, comprising a branched chain alkyl acrylate monomer copolymerized with a minor amount of hydrophilic monomer such as acrylic acid with an appropriate amount of internal crosslinking agent to control polymer particle size, and a surfactant such as a nonylphenol reacted with several moles of ethylene oxide, styrenated phenol ethoxylate, or a phosphate ester of styrenated phenol ethoxylate.
    Type: Grant
    Filed: November 5, 1992
    Date of Patent: January 11, 1994
    Assignee: Halliburton Company
    Inventor: Weldon M. Harms
  • Patent number: 5221790
    Abstract: Mixed polysaccharide compositions, well adopted for flocculating/precipitating solid particulates from liquid dispersions thereof and for the shaping of insulating articles therefrom, comprise (i) at least one polysaccharide prepared by microbial fermentation, the basic recurring structural unit of which comprising both glucose and rhamnose moieties, and (ii) at least one cationic natural polysaccharide or derivative thereof.
    Type: Grant
    Filed: July 30, 1991
    Date of Patent: June 22, 1993
    Assignee: Rhone-Poulenc Chimie
    Inventors: Marie-Madeleine Besnard, Claire David, Magali Knipper
  • 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: 5196527
    Abstract: This invention relates to ion-exchanged fine cellulose particles, porous fine cellulose particles which can be advantageously used as an affinity carrier, and methods of production thereof. These fine particles of the invention have the advantage that they possess excellent pressure-resistant strength and can treat treatment liquors under pressure at a high flowing velocity. Thus, they can be advantageously used industrially in various separation and purification processes.
    Type: Grant
    Filed: February 4, 1992
    Date of Patent: March 23, 1993
    Assignee: Kanebo Ltd.
    Inventors: Shigeru Ookuma, Kouei Igarashi, Masami Hara, Kazuhiro Aso, Hideo Yoshidome, Hiroshi Nakayama, Keizo Suzuki, Kazuhiko Nakajima
  • Patent number: 5137718
    Abstract: A composition for a topically applied therapeutic cream or ointment having effective activity against one or a combination of sources of viral, bacterial, yeast and fungus infections characterized by the ability to penetrate beneath the epidermal layer of the skin. The composition includes a water soluble active component which is formulated with a water soluble organic solid base and a water soluble surfactant to form an aqueous solution having a gel-like consistency. A preferred active ingredient is a povidone-iodine complex. A preferred carrier is hydroxyethylcellulose.
    Type: Grant
    Filed: May 15, 1990
    Date of Patent: August 11, 1992
    Assignee: G&S Medical Ltd
    Inventor: C. Edward Gillespie
  • Patent number: 5124445
    Abstract: Cellulose ethers are disclosed which have sufficient nonionic substitution to render them water soluble and which are further modified with a C.sub.10 to C.sub.24 long chain alkylaryl group in an amount between 0.2% by weight and the amount which makes them less than 1% by weight soluble in water. Hydroxyethylcellulose is a preferred water soluble cellulose ether for modification according to the invention. These products exhibit substantially improved viscosifying effects compared to their unmodified cellulose ether counterparts, and provide good leveling and sag resistance in latex paints. Preferred alkylaryl groups are nonylphenyl, dodecylphenyl, and dinonylphenyl. Included are cellulose ethers with spacer groups of various lengths between the alkylaryl group and the connecting group to the cellulose molecule.
    Type: Grant
    Filed: May 17, 1991
    Date of Patent: June 23, 1992
    Assignee: Aqualon Company
    Inventors: Ernst K. Just, Thomas G. Majewicz, Arjun C. Sau
  • Patent number: 5120838
    Abstract: Cellulose ethers are disclosed which have sufficient nonionic substitution to render them water soluble and which are further modified with a C.sub.10 to C.sub.24 long chain alkylaryl group in an amount between 0.2% by weight and the amount which makes them less then 1% by weight soluble in water. Hydroxyethylcellulose is a preferred water soluble cellulose ether for modification according to the invention. These products exhibit substantially improved viscosifying effects compared to their unmodified cellulose ether counterparts, and provide good leveling and sag resistance in latex paints. Preferred alkylaryl groups are nonylphenyl, dodecylphenyl, and dinonylphenyl. Included are cellulose ethers with spacer groups of various lengths between the alkylaryl group and the connecting group to the cellulose molecule.
    Type: Grant
    Filed: October 30, 1989
    Date of Patent: June 9, 1992
    Assignee: Aqualon Company
    Inventors: Ernst K. Just, Thomas G. Majewicz, Arjun C. Sau
  • Patent number: 5093489
    Abstract: A modified cellulose and/or chitin 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 and/or chitin derivatives is also disclosed.
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: March 3, 1992
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 5093486
    Abstract: A modified cellulose and/or chitin 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 and/or chitin derivatives is also disclosed.
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: March 3, 1992
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 5093488
    Abstract: A modified cellulose and/or chitin 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 and/or chitin derivatives is also disclosed.
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: March 3, 1992
    Assignee: Akzo N.V.
    Inventor: Michael Diamantoglou
  • Patent number: 5032682
    Abstract: Silated polysaccharides having 0.005 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: September 28, 1990
    Date of Patent: July 16, 1991
    Assignee: Aqualon Company
    Inventor: Arjun C. Sau
  • Patent number: 5013832
    Abstract: A process for working up water-soluble cellulose derivatives, more especially with flocculation points above 85.degree. C., after removal by condensation of readily volatile constituents of the crude product mixture resulting from an etherification reaction, by suspension of the crude product in hot water and subsequent separation of the suspension and washing liquids, wherein the separation of the suspension and washing liquids is carried out at elevated temperature and under pressure applied to the separator as a whole.
    Type: Grant
    Filed: August 17, 1987
    Date of Patent: May 7, 1991
    Inventors: Wilfried Raehse, Willi Wuest, Guenther Just
  • Patent number: 5004808
    Abstract: A product comprising a water soluble, high molecular weight aminoalkyl-derivative of hydroxyalkyl-cellulose. The molecular weight of said cellulose is at least 50,000 daltons. One of the methods to obtain the product comprises reacting a hydroxyalkyl cellulose in a basic aqueous medium, in the presence of halogenalkylaminohalide compounds, to obtain a hydroxyalkyl cellulose having an alkylamino group which can be used as such or further reacted in the presence of an amide reducing agent, for instance sodium cyanoborohydride and a carbohydrate residue selected from the group consisting of mono-, di-, oligo-saccharides and starch.
    Type: Grant
    Filed: July 7, 1988
    Date of Patent: April 2, 1991
    Assignee: Domtar Inc.
    Inventors: Manssur Yalpani, Magdy M. Abdel-Malik
  • Patent number: 5001231
    Abstract: Carboxymethylhydroxyethyl (CMHEC), starch and guar are preferred polysaccharides providing at least a 1% solution viscosity of 1000 cps at 25 C. An invert emulsion for oil drilling or paper manufacture comprises on a weight percent basis:______________________________________ Diesel, mineral or paraffin oil 40-60 Imidazole surfactant 1-4 Water 0-10 Organophilic clay 0.5-5.
    Type: Grant
    Filed: November 20, 1989
    Date of Patent: March 19, 1991
    Assignee: Aqualon Company
    Inventor: Jose Zapico
  • 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: 4942128
    Abstract: The present invention involves a method of producing cellulose. This method comprises inoculating a quantity of nutrient medium comprising a polysaccharide derivative such as carboxymethylcellulose (CMC) with a cellulose-producing microorganism. The inoculated medium is then aerobically incubated to facilitate the production of cellulose. The step of substantially drying the cellulose may be added for certain products. Substantially dried cellulose resulting from this procedure is highly absorbent, tending to retain its absorbent properties during repeated wetting and drying, and is usable where such absorbency is desired.A subject of the present invention is a composition of matter consisting essentially of such cellulose in a native or substantially dried form. Microbial cellulose produced in the presence of carboxymethyl cellulose may be substantially dried by many means known to those skilled in the art. This drying may be, for example, by washing with a non-aqueous hydrophilic solvent or by air-drying.
    Type: Grant
    Filed: March 6, 1987
    Date of Patent: July 17, 1990
    Assignee: Board of Regents, the University of Texas System
    Inventor: R. Malcolm Brown, Jr.
  • 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: 4902733
    Abstract: An aqueous protective coating composition comprising (a) a nonionic, water-soluble 3-alkoxy-2-hydroxypropylhydroxyethylcellulose wherein the alkyl moiety is a straight or branched chain alkyl group having 6 to 24 carbon atoms and (b) a film forming latex, is disclosed.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: February 20, 1990
    Assignee: Aqualon Company
    Inventor: John D. Angerer
  • Patent number: 4803264
    Abstract: The invention provides a process for the preparation of a polysaccharide in oil dispersion which comprises the steps of(a) forming a water-in-oil emulsion by dispersing in oil an aqueous solution of polysaccharide, in the presence of at least one dispersion promoter,(b) drying the resulting emulsion azeotropically, and(c) physically isolating from the resulting azeotropically dried residue an oil phase containing oil and dispersion promoter and a polysaccharide in oil dispersion in the form of a suspension phase containing polysaccharide, dispersion promotor and oil;and a polysaccharide in oil dispersion prepared by the process containing 40 to 50% w/w polysaccharide and 3 to 4.5% w/w of at least one dispersion promoter.
    Type: Grant
    Filed: November 25, 1986
    Date of Patent: February 7, 1989
    Assignee: Shell Oil Company
    Inventors: Wilhelmus J. Krijnen, Jacob B. Roest, Jacob Bloemheuvel
  • Patent number: 4728731
    Abstract: An improved reactor (and process using the same) comprising multistage stirrer elements and baffles, which has particular dimensional ratios between the reactor diameter, the width and spacing of the stirrer elements, and the baffles. The reactor is particularly adapted for the production of polysaccharide ethers, especially cellulose ethers.
    Type: Grant
    Filed: March 10, 1986
    Date of Patent: March 1, 1988
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Wilfried Raehse, Willi Wuest, Norbert Kuehne
  • Patent number: 4691013
    Abstract: A process for producing a modified hydroxyethyl cellulose comprising the steps of:allowing hydroxyethyl cellulose to be swollen in a solvent; andmixing the hydroxyethyl cellulose swollen in the solvent, with a 2-mercapto benzimidazole compound having the formula (I): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 independently represent hydrogen, methyl, or ethyl, and X is hydrogen, an alkali metal, an alkaline earth metal, or ammonium.
    Type: Grant
    Filed: August 27, 1986
    Date of Patent: September 1, 1987
    Assignees: Lion Corporation, Nitto Chemical Industry Co., Ltd
    Inventors: Yukihiko Sekimoto, Makoto Yanagita, Shoichi Kanda
  • 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: 4661266
    Abstract: A completion and workover fluid which comprises an aqueous liquid medium containing hydroxyethyl cellulose, an inorganic salt selected from the group consisting of calcium chloride, calcium bromide and zinc bromide, and a component selected from the group consisting of the following components:(1) thiol derivatives of heterocyclic compounds;(2) thioamide derivatives;(3) at least one compound selected from the group consisting of thiuram disulfide compounds, thiuram monosulfide compounds and dithiocarbamate compounds;(4) benzothiazole; and(5) a copper compound and an iodine compound in combination.
    Type: Grant
    Filed: July 16, 1985
    Date of Patent: April 28, 1987
    Assignee: Nitto Chemical Industry Co., Ltd.
    Inventors: Shoichi Kanda, Makoto Yanagita, Yukihiko Sekimoto
  • Patent number: 4614601
    Abstract: A completion and workover fluid is described, containing a soluble salt, a hydroxyethyl cellulose and at least one compound selected from 2-mercaptobenzimidazole compounds, 2-mercaptobenzothiazole compounds, 2-mercaptothiazoline and 2-thioimidazolidone.
    Type: Grant
    Filed: April 2, 1985
    Date of Patent: September 30, 1986
    Assignee: Nitto Chemical Industry Co., Ltd.
    Inventors: Yukihiko Sekimoto, Makoto Yanagida, Shoichi Kanda
  • Patent number: 4550161
    Abstract: The process for preparing mixed cellulose ethers proceeds in the following steps:(a) alkalizing of the cellulose,(b) etherifying of the alkali cellulose in the presence of a base by using at least one etherifying agent which requires, for the reaction with cellulose, a catalytic and sub-stoichiometric quantity of a base, and(c) increasing the quantity of base, and(d) etherifying the cellulose ether so prepared by using at least one etherifying agent which requires, for the reaction with cellulose, an at least stoichiometric quantity of a base or a catalytic and substoichiometric quantity of a base, increased over the quantity used in (a),with at least one inert organic solvent being used as a dispersing auxiliary in at least one of the steps and water being present in all steps, wherein mixed etherification leads to a water-soluble product and dimethoxyethane, an alkanol, an alkanediol and/or an alkoxyalkanol are used as the organic solvents.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: October 29, 1985
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Utz-Hellmuth Felcht, Gerhard Buchberger
  • 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: 4508895
    Abstract: A process for the production of water-soluble hydroxyalkyl methyl cellulose by the alkalization of the cellulose with sodium hydroxide and by subsequent etherification with alkylene oxide in an inert solvent, characterized in that before etherification, the alkali content of the aqueous alkali cellulose is reduced to 0.3-0.8 mols of NaOH/mol of cellulose by washing out with a suitable, known solvent (mixture), and is then etherified with an alkylene oxide in the liquid phase.
    Type: Grant
    Filed: February 13, 1984
    Date of Patent: April 2, 1985
    Assignee: Bayer Aktiengesellschaft
    Inventor: Klaus Balser
  • Patent number: 4491661
    Abstract: A process is disclosed for the preparation of water-soluble cellulose ethers, comprising the steps of activating cellulose with ammonia, alkalizing the activated cellulose, and etherifying the alkali cellulose. In the process, the activated cellulose is alkalized in the presence of ammonia and, optionally, in the presence of an organic solvent, and the ammonia is removed from the alkali cellulose in the presence of the alkalizing agent and, optionally, the organic solvent. Etherification proceeds in a medium which contains at least portions of said organic solvent. The organic solvent comprises, in particular, an alkanol which has from 1 to 6 carbon atoms. For the etherification step, carboxymethylation or hydroxyethylation is preferred.
    Type: Grant
    Filed: October 27, 1983
    Date of Patent: January 1, 1985
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Karl Bredereck, Emy Togelang
  • Patent number: 4460766
    Abstract: In modern processes for preparing cellulose ethers containing one or more types of substituents, such as MC, CMC, HEC, HPC, MHEC or EHEC, cellulose is reacted with an etherifying agent in the presence of water, base and at least one inert organic solvent (as a dispersing auxiliary). Dimethoxyethane (ethylene glycol dimethyl ether) is employed as a new organic solvent for these syntheses, particularly in quantities of 1 to 30 parts by weight per part by weight of cellulose.
    Type: Grant
    Filed: November 19, 1982
    Date of Patent: July 17, 1984
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Utz-Hellmuth Felcht, Eberhard Perplies
  • Patent number: 4435564
    Abstract: Processes are disclosed for activating hydroxyethyl cellulose (HEC) such that the HEC will disperse and hydrate in compatible heavy brines having a density greater than about 13.5 pounds per gallon containing one or more salts selected from the group consisting of calcium chloride, calcium bromide, zinc chloride, and zinc bromide, at ambient temperatures such that the HEC will be at least 80% hydrated within one hour.The activation process comprises admixing the HEC with an organic liquid which has no appreciable swelling effect on the HEC and an amine activator.The invention also provides activated HEC compositions and a process of increasing the viscosity of a heavy brine utilizing these compositions.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: March 6, 1984
    Assignee: Venture Innovations, Inc.
    Inventor: Roy F. House
  • 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
  • Patent number: 4396433
    Abstract: The application discloses a gel-forming composition based on (a) water, (b) a water-soluble cellulose mixed ether having at least one nonionic substituent from the group comprising hydroxyalkyl and alkyl and at least one anionic phosphorus-containing substituent, and (c) a salt containing a cation which is at least divalent. The phosphorus-containing substituent is a phosphonoalkyl group or a p-alkylphosphinoalkyl group. The application also relates to a process for the preparation of a gel from this composition, to the reversible reversing of the gel by the addition of an agent which complexes the cation, e.g. in the case of Al.sup.3+ ions, Fe.sup.3+ ions, Zr.sup.4+ ions or ZrO.sup.2+ ions, by means of an amount of fluoride ions, and to the use of this gel-forming compostion in the secondary production of petroleum.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: August 2, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Lothar Brandt, Arno Holst
  • Patent number: 4366310
    Abstract: Molecular coordination complexes are formed between a cellulose polymer and a non-polar solid aliphatic alcohol containing 8 to 18 carbon atoms optionally substituted with an aliphatic group containing 8 to 18 carbon atoms by solvating the polymer with a volatile polar solvent and reacting the solvated cellulose polymer directly with the aliphatic alcohol, preferably as a melt. The resulting composition may be dried. This constitutes the complex. The composition has utility as a matrix in controlled release formulations since it has a uniform porosity which may be varied.
    Type: Grant
    Filed: December 10, 1980
    Date of Patent: December 28, 1982
    Assignee: Euroceltique, S.A.
    Inventor: Stewart T. Leslie
  • Patent number: 4339574
    Abstract: This invention is directed to a method for the continuous production of alkyl cellulose by reacting alkali cellulose with alkylating agents in the presence of inert liquids, wherein:(a) powdered cellulose is reacted with aqueous-alcoholic alkali metal hydroxide solution at temperatures of from about 20.degree. to 80.degree. C. to form alkali cellulose;(b) oxygen is completely removed from the alkali cellulose reaction mixture of step (a) and the water content is reduced to about 2.5 to 6.0 moles per anhydroglucose unit; and(c) the reaction mixture from step (b) is reacted with at least a stoichiometric amount, but not more than with a molar excess of up to about 50%, based on the alkali metal hydroxide, of an alkylating agent in an inert liquid boiling at a temperature of from about 80.degree. to 160.degree. C., the reaction being carried out continuously in stirred tanks-in-series with 2 to 10 units.
    Type: Grant
    Filed: July 7, 1980
    Date of Patent: July 13, 1982
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Willi Wust, Hasso Leischner, Wilfried Rahse, Franz-Josef Carduck, Norbert Kuhne
  • Patent number: 4321261
    Abstract: A contact lens solution is provided for wetting, soaking and lubricating of hard contact lenses, particularly those carrying an ionic charge. The solution contains an ionic polymer of cationic or anionic charge that interacts with an oppositely charged surface of a contact lens forming an interfacial polyelectrolyte complex. This polyelectrolyte complex provides increased, long lasting lens wettability leading to a cushioning and lubricating effect with the eyelid and the cornea.
    Type: Grant
    Filed: June 25, 1979
    Date of Patent: March 23, 1982
    Assignee: Polymer Technology Corporation
    Inventors: Edward J. Ellis, Joseph C. Salamone
  • Patent number: 4310663
    Abstract: A continuous process for manufacturing water-soluble hydroxyalkyl cellulose, and water-soluble mixed ethers based on hydroxyalkyl cellulose, comprising producing a slurry comprising (by weight) 1 part cellulose, 0.02 to 0.6 parts alkali metal hydroxide, 5 to 10 parts inert organic solvent, and 0.4 to 2.5 parts water; continuously feeding the slurry to a first elevated pressure reactor and mixing the slurry therein with at least one normally gaseous etherifying agent which has been liquified under pressure; maintaining the slurry at a temperature up to 40.degree. C., and a gauge pressure up to 3 bars, for 15 to 90 minutes, to give a degree of substitution from 0.2 to 1.
    Type: Grant
    Filed: June 4, 1980
    Date of Patent: January 12, 1982
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Josef Hilbig, Arno Holst, Hans Kunkler, Klaus Stolting, Wolfgang Schminke
  • Patent number: 4298728
    Abstract: In preparation of hydroxyethyl ethers of cellulose, ethylene oxide efficiency of the reaction and solubility characteristics of the product are improved by using alkali cellulose which has been prepared in the presence of boric acid or a boric acid salt.
    Type: Grant
    Filed: June 3, 1980
    Date of Patent: November 3, 1981
    Assignee: Hercules Incorporated
    Inventors: Thomas G. Majewicz, Walter S. Ropp
  • Patent number: 4272526
    Abstract: The present invention relates to a chloral derivative having the general formula ##STR1## in which Y' is a polysaccharide consisting of a chain of anhydroglucose, modified anhydroglucose or uronic acid units as substituent group and in which R is selected from --H, --COCH.sub.2 OH, --[(CH.sub.2).sub.n 0].sub..chi. --H in which n is 2 to 5 and .chi. is 1 to 7; --CH.sub.2 OSO.sub.2 X' or --CH.sub.2 COOX' in which X' is NH.sub.4 or a single equivalent of a non-toxic metallic cation, --(CH.sub.2).sub.n H where n is 1 to 7, --(CH.sub.2).sub.n (OH).sub..chi. Y where Y is --H or --CH.sub.3 n is 1 to 7, .chi. is 1 to 12 and the --OH groups are attached to any or all of the carbon atoms by substitution and wherein when Y.sup.1 is a chain of unmodified anhydroglucose units, these units have the following configurations:.alpha.-D-glucopyranosyl units having a predominantly 1-4 linkage.beta.-D-glucopyranosyl units having a predominantly 1-4 linkage and/or.beta.
    Type: Grant
    Filed: May 8, 1979
    Date of Patent: June 9, 1981
    Assignee: Macarthys Pharmaceuticals Limited
    Inventors: David E. Simpkins, John B. O. Taylor
  • Patent number: 4247688
    Abstract: A composition and process are provided for making precipitated hydroxyethyl cellulose by dissolving a hydroxyethyl cellulose having a molar substitution of less than 1.0, and a degree of substitution of less than about 0.64 in mixture of water and a tertiary amine oxide solvent, to provide a solution containing from about 10% to about 28% water. Shaped articles can be formed from the solutions of the invention.
    Type: Grant
    Filed: July 2, 1979
    Date of Patent: January 27, 1981
    Assignee: Akzona Incorporated
    Inventors: Neal E. Franks, Julianna K. Varga
  • Patent number: 4097667
    Abstract: Disclosed is a process for the chemical modification of a water-soluble cellulose ether, which comprises reacting the ether with a chloroformic acid ester in an aqueous organic medium containing alkali hydroxide, whereby the cellulose ether is rendered at least partially insoluble in water. The modified cellulose ether may be easily dispersed in water and redissolved to form a smooth solution of the original water-soluble ether by adding sufficient alkali to the dispersion to reuse its pH to at least about 11, preferably to about 12.
    Type: Grant
    Filed: December 16, 1976
    Date of Patent: June 27, 1978
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Arno Holst, Michael Kostrzewa
  • Patent number: 4091205
    Abstract: In the process for the preparation of low-substituted cellulose ethers comprising the successive steps of etherification of alkali cellulose, neutralization of the crude cellulose ether, washing, drying and pulverization, the neutralization step is carried out in two stages, i.e., by first employing 5 to 80% of an acid stoichiometrically required and then adding an additional amount of the acid to complete neutralization. The cellulose ethers thus prepared can readily be pulverized into fine powder having a very good flowing property and yet an excellent binding force, and work as a suitable disintegrator in tablets.
    Type: Grant
    Filed: November 26, 1975
    Date of Patent: May 23, 1978
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Yoshiro Onda, Hiroaki Muto, Hiroshi Suzuki
  • Patent number: 4084591
    Abstract: Novel absorber for the blood and the like, particularly a tampon for menses, which is made of the filaments of a lower alkyl or a lower hydroxyalkyl substituted cellulose ether. The absorber is insoluble in the blood and the like when it is used, but it is dispersible and soluble in water when it is thrown away.
    Type: Grant
    Filed: February 11, 1976
    Date of Patent: April 18, 1978
    Assignee: Eisai Co., Ltd.
    Inventors: Toshio Takebe, Takashi Yamazaki
  • Patent number: 4084060
    Abstract: A process for the synthesis of hydroxyethyl cellulose having improved resistance of enzyme catalyzed hydrolysis is provided by employment of a controlled, optimum amount of available water for swelling the cellulose in aqueous caustic reaction medium in hydroxy ethoxylation sequences of first high and then low ratios of caustic:cellulose.
    Type: Grant
    Filed: November 18, 1976
    Date of Patent: April 11, 1978
    Assignee: Union Carbide Corporation
    Inventors: Joseph Edward Glass, Jr., Roy Gale Lowther
  • Patent number: RE34904
    Abstract: Cellulose ethers are disclosed which have sufficient nonionic substitution to render them water soluble and which are further modified with a C.sub.10 to C.sub.24 long chain alkylaryl group in an amount between 0.2% by weight and the amount which makes them less than 1% by weight soluble in water. Hydroxyethylcellulose is a preferred water soluble cellulose ether for modification according to the invention. These products exhibit substantially improved viscosifying effects compared to their unmodified cellulose ether counterparts, and provide good leveling and sag resistance in latex paints. Preferred alkylaryl groups are nonylphenyl, dodecylphenyl, and dinonylphenyl. Included are cellulose ethers with spacer groups of various lengths between the alkylaryl group and the connecting group to the cellulose molecule.
    Type: Grant
    Filed: July 8, 1993
    Date of Patent: April 11, 1995
    Assignee: Hercules Incorporated
    Inventors: Ernst K. Just, Thomas G. Majewicz, Arjun C. Sau