Carboxamides With Preservative Or Stabilizer Patents (Class 564/4)
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Patent number: 12171717Abstract: The present invention relates to a vial that is at least partially filled with an aqueous formulation of a neurotoxin, preferably botulinum toxin, to the manufacture of the vial and to the use thereof. The aqueous formulation of a neurotoxin is stable in the vial for a prolonged period of time.Type: GrantFiled: October 7, 2019Date of Patent: December 24, 2024Assignee: Merz Pharma GmbH & Co. KGaAInventor: Markus Vogt
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Patent number: 10383834Abstract: Described herein are compositions and methods for intravenous administration of acetaminophen at a single dose level of less than about 1000 mg for the treatment or prevention of pain (e.g., postoperative pain) and/or fever.Type: GrantFiled: May 14, 2018Date of Patent: August 20, 2019Assignee: Mallinckrodt Hospital Products IP LimitedInventors: Mike Allan Royal, James Bradley Breitmeyer
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Patent number: 9616128Abstract: Disclosed herein are injectable compositions containing high concentration of paracetamol or its pharmaceutically acceptable salts wherein the concentration of paracetamol or its pharmaceutically acceptable salt is >150 mg/ml in a judiciously tailored solvent system comprising glycofurol, ethanol, water or a solvent system comprising glycofurol, ethanol, polyethylene glycol, water. The viscosity of the said injectables is <28 cps. Further disclosed is the process for preparing the said injectables. The injectables can be administered by intramuscular route, intravenous route or as intravenous infusion after diluting in one of the routinely used intravenous fluids, infusion solutions of antibacterial, antifungal and amoebicidal drugs and along with anxiolytics (Midazolam injection) or narcotic analgesics (Fentanyl Citrate injection etc) as they remain stable, clear and transparent at least for 6 hours after dilution.Type: GrantFiled: June 29, 2011Date of Patent: April 11, 2017Assignee: Troikaa Pharmaceuticals LtdInventors: Ketan R. Patel, Milan R. Patel, Prakashchandra J. Shah
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Polymerization inhibitor composition and method of inhibiting polymerization of distillable monomers
Patent number: 9447201Abstract: The present invention relates to a polymerization inhibitor composition and a method of inhibiting polymerization of distillable monomers in liquid and evaporated/condensed phases with the polymerization inhibitor composition. The polymerization inhibitor composition is useful for inhibiting polymerization of the distillable monomers during manufacture, purification (e.g., distillation), handling, and storage thereof.Type: GrantFiled: February 18, 2010Date of Patent: September 20, 2016Assignee: DOW GLOBAL TECHNOLOGIES LLCInventors: Kishore K. Kar, Michael D. Cloeter, Olan Stanley Fruchey, Richard S. Harner, Krzysztof Matyjaszewski, Renaud Nicolay, Jaroslav Mosná{hacek over (c)}ek -
Patent number: 9089477Abstract: The present invention relates to a method for the production of a formulation that is stable to oxidation and that is based on paracetamol in an aqueous solvent, comprising the steps of (i) dissolving paracetamol in an aqueous solvent comprising an isotonic agent that is sodium chloride and a buffer agent that is sodium citrate, having a temperature between 65° C. and 95° C. and having pH between 5.0 and 6.0 in a reaction vessel, (ii) replacing the remaining air in the vessel by an inert gas, such as nitrogen, and cooling the solution so formed to a temperature below 38° C., (iii) adding cysteine hydrochloride to the solution without mechanical agitation, and (iv) closing the reaction vessel and mechanically agitating the solution in a nitrogen atmosphere. The further relates to a formulation prepared according to the method.Type: GrantFiled: February 10, 2011Date of Patent: July 28, 2015Assignee: NEOGEN N.V.Inventor: Khaled Al Dandachi Atassi
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Patent number: 8937199Abstract: The present invention provides a process for stabilizing an aqueous acrylamide solution. The present invention also provides a stable aqueous acrylamide solution containing acetaldehyde at a weight ratio relative to acrylamide of 1.5 mg/Kg to 4 mg/Kg.Type: GrantFiled: February 21, 2011Date of Patent: January 20, 2015Assignee: Mistubishi Rayon Co., Ltd.Inventors: Makoto Kanou, Norifumi Hagiya
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Patent number: 8741959Abstract: The invention relates to an aqueous pharmaceutical composition, preferably an infusion solution, for parenteral administration which contains paracetamol and has an electrical conductivity of not more than 200 ?S cm?1.Type: GrantFiled: April 19, 2010Date of Patent: June 3, 2014Assignee: Fresenius Kabi Deutschland GmbHInventors: David Dasberg, Georg Achleitner, Christiane Aichholzer
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Patent number: 8637496Abstract: The invention relates to the use of compounds having a monogalactosyldiacylglycerol (MGDG) synthase inhibitory activity as herbicide or algaecide, and to herbicide and algaecide compositions containing at least one of these compounds.Type: GrantFiled: June 2, 2008Date of Patent: January 28, 2014Assignees: Commissariat a l'Energie Atomique, Centre National de la Recherche ScientifiqueInventors: Anne-Laure Bonneau, Cyrille Botte, Michael Deligny, Nadia Saidani, Hélène Hardre, Bernard Rousseau, Roman Lopez, Eric Marechal
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Patent number: 8404891Abstract: The present invention concerns a liquid formulation that is stable to oxidation and that is based on paracetamol in an aqueous solvent obtainable by the following steps: (i) dissolving in a reaction vessel paracetamol in an aqueous solvent having a temperature between 65° C. and 95° C., and having pH between 5.0 and 6.0; (ii) cooling the solution so formed to a temperature equal to or above 35° C. and below 40° C. under an atmosphere of nitrogen; (iii) adding cysteine hydrochloride and sodium hydroxide simultaneously to the solution without stirring; (iv) closing the reaction vessel, and stirring the solution of step iii) in a nitrogen atmosphere. It further relates to a method for preparing the formulation.Type: GrantFiled: September 3, 2010Date of Patent: March 26, 2013Assignee: Neogen N.V.Inventor: Khaled Al Dandachi Atassi
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Publication number: 20120316362Abstract: The present invention provides a process for stabilizing an aqueous acrylamide solution. The present invention also provides a stable aqueous acrylamide solution containing acetaldehyde at a weight ratio relative to acrylamide of 1.5 mg/Kg to 4 mg/Kg.Type: ApplicationFiled: February 21, 2011Publication date: December 13, 2012Inventors: Makoto Kanou, Norifumi Hagiya
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Patent number: 8178121Abstract: The present invention refers to ready-to-use highly stable paracetamol injectable solutions, prepared by mixing paracetamol, water, propylene glycol, and a citrate buffer. (pH 4.5 to 6.5), and by heating said solution under preset conditions. The resulting solution may be stored for an extended period of time within a wide range of temperatures, with no paracetamol precipitation and/or its chemical modification.Type: GrantFiled: October 15, 2002Date of Patent: May 15, 2012Assignees: Baxter International Inc., Baxter Healthcare S.A.Inventor: Tho Nguyen-Xuan
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Patent number: 7858817Abstract: This invention relates to new transition metal complexes for use in olefin polymerization and oligomerization. The active complex is a pyridine amide having a metallocenyl substituent as part of the ligand structure. The invention also relates to novel precursors for the ligand systems of such complexes obtained from metallocenyl-substituted pyridine compounds through sequences involving addition-condensation or lithium-halogen exchange (with subsequent metathesis) reactions.Type: GrantFiled: March 10, 2008Date of Patent: December 28, 2010Assignee: ExxonMobil Chemical Patents Inc.Inventor: John R. Hagadorn
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Patent number: 7675058Abstract: Compounds having two reactive functional groups are described that can be used to provide a connector group between a substrate and an amine-containing material. The first reactive functional group can be used to provide attachment to a surface of a substrate. The second reactive functional group is a N-sulfonylaminocarbonyl group that can be reacted with an amine-containing material, particularly a primary aliphatic amine, to form a carbonylimino-containing connector group. The invention also provides articles and methods for immobilizing amine-containing materials to a substrate.Type: GrantFiled: October 27, 2006Date of Patent: March 9, 2010Assignee: 3M Innovative Properties CompanyInventors: Karl E. Benson, Moses M. David, Cary A. Kipke, Brinda B. Lakshmi, Charles M. Leir, George G. Moore, Rahul Shah
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Patent number: 7102032Abstract: In the synthesis of an amide compound through reaction of an acyl fluoride group-bearing compound with an amino compound, a reaction mixture contains the amide compound and hydrogen fluoride or a hydrofluoric acid amine salt. The amide compound is recovered in high purity form by adding an oxide, carbonate or hydroxide of an alkaline earth metal to the reaction mixture to convert the hydrogen fluoride or hydrofluoric acid amine salt to an alkaline earth metal fluoride salt that can be readily removed by filtration.Type: GrantFiled: April 21, 2004Date of Patent: September 5, 2006Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Yasunori Sakano, Noriyuki Koike
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Patent number: 7002041Abstract: An amide composition containing an unsaturated amide, a sulfur-containing compound, and a weak acid salt. The composition can include an amide in crystalline form or the composition can be in form of aqueous solution. The composition can exhibit improved stability whereby polymerization of the amide is inhibited.Type: GrantFiled: November 4, 2002Date of Patent: February 21, 2006Assignee: Mitsui Chemicals, Inc.Inventors: Takeya Abe, Kenju Sasaki
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Patent number: 6992218Abstract: A method for obtaining aqueous formulations with easily oxidizable active principles, notably phenols, stable over a prolonged period, comprising subjecting them to extreme deoxygenation by bubbling with an inert gas and/or placing wider vaccum, protecting them against possible resorption of oxygen by keeping them under an inert gas atmosphere, by filling, under inert gas, into bottles previously cleared of air by insufflation with inert gas, then subjecting them, while stoppering, to low pressure as obtained in the bottle, of 65,000 Pa maximum, to obtain aqueous solutions having a residual oxygen concentration in the solution below 2 ppm, and preferably of the order of 1 ppm and even 0.5 ppm useful as injectable preparations having an oxygen concentration in the solution below 2 ppm.Type: GrantFiled: June 6, 2001Date of Patent: January 31, 2006Assignee: Pharmatop SCRInventors: Francois Dietlin, Daniele Fredj
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Publication number: 20030088125Abstract: An amide composition containing an unsaturated amide, a sulfur-containing compound, and a weak acid salt. The composition can include an amide in crystalline form or the composition can be in form of aqueous solution. The composition can exhibit improved stability whereby polymerization of the amide is inhibited.Type: ApplicationFiled: November 4, 2002Publication date: May 8, 2003Applicant: Mitsui Chemicals, Inc.Inventors: Takeya Abe, Kenju Sasaki
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Publication number: 20030032832Abstract: It has been discovered that the polymerization of unsaturated compounds, such as butadiene, may be inhibited by the addition of a diene and/or alkanolamine inhibitor. The inhibitor is believed to catalytically destroy peroxides present, such as hydrogen peroxide, which may be present in trace amounts. Particularly useful inhibitors include, but are not limited to, ethylenediamine (EDA) and monoethanolamine (MEA).Type: ApplicationFiled: June 20, 2001Publication date: February 13, 2003Inventor: Muslim D. Shahid
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Patent number: 6417396Abstract: A method for enhancing the purity of a desired compound comprising: Step (a) treating a crude reaction product which contains at least one desired compound, unreacted starting materials and/or byproducts with at least one bifunctional quenching agent that is capable of selective covalent reaction with unwanted byproducts, or excess reagents; Step (b) allowing the quenching agent to covalently react with unreacted starting materials and/or byproducts to afford a derivatized compound of the quenching agent: and Step (c) isolating the desired compound is described as well as novel quenching agents and methods for their use in the rapid purification of synthetic intermediates and products in synthesis, combinatorial chemistry, and automated organic synthesis.Type: GrantFiled: May 25, 2000Date of Patent: July 9, 2002Inventor: Sham Nikam
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Patent number: 6121488Abstract: A method for enhancing the purity of a desired compound comprising:Step (a) treating a crude reaction product which contains at least one desired compound, unreacted starting materials and/or byproducts with at least one bifunctional quenching agent that is capable of selective covalent reaction with unwanted byproducts, or excess reagents;Step (b) allowing the quenching agent to covalently react with unreacted starting materials and/or byproducts to afford a derivatized compound of the quenching agent: andStep (c) isolating the desired compound is described as well as novel quenching agents and methods for their use in the rapid purification of synthetic intermediates and products in synthesis, combinatorial chemistry, and automated organic synthesis.Type: GrantFiled: September 21, 1998Date of Patent: September 19, 2000Assignee: Warner-Lambert CompanyInventor: Sham Nikam
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Patent number: 6028222Abstract: Novel stable paracetamol compositions for use in therapeutic chemistry and specifically galenic pharmacy are disclosed. The compositions contain a solution of paracetamol in an aqueous solvent combined with a buffer having a pH of 4 to 8, and a free radical capturing agent. A water-insoluble inert gas is carefully bubbled through the aqueous solvent to remove oxygen from the medium. Said compositions may also be combined with a centrally or peripherally acting analgesic agent, and are provided as injectable compositions for relieving pain.Type: GrantFiled: June 5, 1998Date of Patent: February 22, 2000Assignee: SCR PharmatopInventors: Francois Dietlin, Daniele Fredj
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Patent number: 5888473Abstract: Boron neutron capture therapy can utilize X.sub.y B.sub.20 H.sub.17 L where X is an alkali metal, y is 1 to 4, and L is a two electron donor such as NH.sub.3, and Na.sub.2 B.sub.10 H.sub.9 NCO, among others. These borane salts may be used free or encapsulated in liposomes. Liposomes may have embedded within their bilayers carboranes to increase the amount of delivered .sup.10 B and/or to increase the tumor specificity of the liposome.Type: GrantFiled: August 3, 1995Date of Patent: March 30, 1999Assignee: The Regents of the University of CaliforniaInventors: M. Frederick Hawthorne, Debra Arliene Feakes, Kenneth John Shelly
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Patent number: 5840976Abstract: Disclosed herein is a method of improving the stability of N-vinylamides. A quinone or alkali-modified quinone is added to the N-vinylamide. The loss of the N-vinylamide due to polymerization and/or decomposition during distillation is significantly reduced.Type: GrantFiled: September 23, 1996Date of Patent: November 24, 1998Assignee: Mitsubishi Chemical CorporationInventors: Shin-Ichi Sato, Kiyoji Kuma, Toshimitu Inoue, Yuuichi Nishida
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Patent number: 5670692Abstract: Ethylenically unsaturated monomers are protected from premature polymerization during manufacture and storage by the incorporation therein of an effective stabilizing amount of a 7-substituted quinone methide compound.Type: GrantFiled: August 27, 1996Date of Patent: September 23, 1997Assignee: Ciba-Geigy CorporationInventors: Peter Nesvadba, Samuel Evans, Matthew E. Gande, Volker H. von Ahn, Roland A. E. Winter
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Patent number: 5554792Abstract: Disclosed herein is an N-vinylformamide composition comprising 250 ppm by weight or less of formic acid based on N-vinylformamide.According to the invention, the purity and polymerizing activity of N-vinylformamide are preserved for a long time.Type: GrantFiled: April 13, 1995Date of Patent: September 10, 1996Assignee: Mitsubishi Kasei CorporationInventors: Shigeru Sawayama, Kohichi Satoh
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Patent number: 5498791Abstract: A synergistic mixture of a carbonate and/or bicarbonate with a phosphonate, especially an organoamino methylene phosphonate or an N-oxide thereof, inhibits or reduces nitrosamine contamination during preparation, storage and/or heating of products which are susceptible to contamination with nitrosamine.Type: GrantFiled: January 20, 1995Date of Patent: March 12, 1996Assignee: Albright & Wilson, LimitedInventors: Michael Blezard, Glyn R. Jones, Moharam Ghadimi
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Patent number: 5442113Abstract: A synergistic mixture of a carbonate and/or bicarbonate with a phosphonate, especially an organoamino methylene phosphonate or an N-oxide thereof, inhibits or reduces nitrosamine contamination during preparation, storage and/or heating of products which are susceptible to contamination with nitrosamine.Type: GrantFiled: February 1, 1993Date of Patent: August 15, 1995Assignee: Albright & Wilson LimitedInventors: Michael Blezard, Glyn R. Jones, Moharam Ghadimi
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Patent number: 5354903Abstract: This invention is directed to producing highly concentrated solutions of methylenebisacrylamide and thereafter blending with ionogenous acrylic monomers to produce low porosity, highly crosslinked, water insoluble polymers.Type: GrantFiled: December 24, 1992Date of Patent: October 11, 1994Assignee: Ionics, IncorporatedInventor: Russell J. MacDonald
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Patent number: 5352828Abstract: A process for the stabilization of an aqueous acrylamide solution is described which includes adding at least one compound selected from water-soluble monocarboxylic acid salts having at least two carbon atoms to an aqueous solution of acrylamide in an amount of from 20 to 5,000 ppm as acid per acrylamide. According to the present invention, a high purity aqueous acrylamide solution which is markedly stable, even under an iron surface-contacting condition, without causing problems such as the polymerization of acrylamide can be provided by adding a water-soluble monocarboxylic acid salt having at least two carbon atoms.Type: GrantFiled: May 19, 1992Date of Patent: October 4, 1994Assignee: Nitto Chemical Industry Co., Ltd.Inventors: Susumu Seki, Akihisa Furuno
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Patent number: 5326909Abstract: A method of stabilizing N-vinylformamide, which may contain customary polymerization inhibitors, against polymerization during storage or transport, comprises adding to the N-vinylformamide monomers of the general formula ##STR1## where R+H, CH.sub.3 ##STR2## R.sup.2 +C.sub.1 -C.sub.4 -alkyl, as stabilizer in amounts of from 1 to 99 .degree.6 by weight, based on the mixture.Type: GrantFiled: May 24, 1993Date of Patent: July 5, 1994Assignee: BASF AktiengesellschaftInventors: Michael Kroener, Jacques Dupuis
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Patent number: 5292950Abstract: A composition of an N,N-dialkylaminoalkyl(meth)acrylamide of the following formula (II), which has an improved storageability and which contains an N,N-dialkylhydroxylamine of the following formula (I) in an amount of from 10 to 10,000 ppm: ##STR1## where R.sub.1 and R.sub.2 each independently represent an alkyl group having ##STR2## where R.sub.3 represents a hydrogen atom or a methyl group, R.sub.4 and R.sub.5 each independently represent an alkyl group having from 1 to 4 carbon atoms; andn represents an integer of from 2 to 4.Type: GrantFiled: November 13, 1990Date of Patent: March 8, 1994Assignees: Kohjin Co., Ltd., Sumitomo Chemical Co., Ltd.Inventors: Hiroshi Oka, Yasutaka Doi, Takashi Maruyama
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Patent number: 5223644Abstract: Bicarbonates and/or carbonates are used in greater than catalytic amounts to inhibit the formation of nitrosamines during the preparation, storage and/or use of amine oxides.Type: GrantFiled: February 3, 1992Date of Patent: June 29, 1993Assignee: Albright & Wilson LimitedInventors: Michael Blezard, Glyn R. Jones
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Patent number: 5169598Abstract: A method for inhibiting corrosion of ferrous surfaces in an acidic, aqueous medium having a temperature of at least about 200.degree. F. is disclosed. The method comprises incorporating into the mediumn a corrosion inhibiting amount of a corrosion inhibitor comprising the reaction product of an aldehyde and a composition corresponding to the formula: ##STR1## wherein R.sup.1 is a hydrocarbon group, R.sup.2 and R.sup.3 are independently selected from H and alkyl, R.sup.4 is H, alkyl, alkanol or (alkylene-N).sub.n H wherein n is at least one, and x is 2 or 3. The present invention is also directed to a such method in which the corrosion inhibitor comprises a compound corresponding to the formula: ##STR2## wherein R.sup.1, R.sup.2, and R.sup.3 and x are defined as above.Type: GrantFiled: May 29, 1991Date of Patent: December 8, 1992Assignee: Petrolite CorporationInventors: Michael J. Zetlmeisl, Eddie C. French
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Patent number: 5043468Abstract: The present invention relates to a process and compositions for delaying the gelling of vinyl monomers in an aqueous medium in the presence of a polymerization initiator, by employing a polymerization inhibitor consisting of an N-nitrosophenylamine salt in combination with an aminocarboxylic acid. The composition is used for plugging circulation losses when drilling at great depth.Type: GrantFiled: November 24, 1989Date of Patent: August 27, 1991Assignee: Rhone-Poulenc ChimieInventors: Robert Maurer, Michel Landry
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Patent number: 5025106Abstract: Disclosed is a process for the preparation of aqueous solutions of acetoacetamide wherein diketene and aqueous ammonia having an ammonia concentration of about 6.0 to 9.0 weight percent are continuously fed to a reaction zone at rates which maintain in the reaction zone a pH of about 7.0 to 8.2 and a residence time of about 20 to 150 minutes while (i) maintaining the temperature of the reaction zone at about 40.degree. to 75.degree. C. and (ii) subjecting the contents of the reaction zone to vigorous agitation. An aqueous product solution having an acetoacetamide concentration of about 25 to 35 weight percent is continuously removed from the reaction zone.Type: GrantFiled: October 22, 1990Date of Patent: June 18, 1991Assignee: Eastman Kodak CompanyInventor: Steven L. Cook
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Patent number: 4859796Abstract: The present invention relates to a process for the preparation of an N-dialkylaminoalkyl(meth)acrylamide of formula: ##STR1## in which: R.sub.1 is a methyl radical or a hydrogen atom,R.sub.2 is a straight-chain or branched alkyl group containing at most 10 carbon atomsR.sub.3 and R.sub.4, which are identical or different, may be:either two aliphatic alkyl groups containing from 1 to 4 carbon atoms,or R.sub.3 is an aliphatic alkyl group containing from 1 to 4 carbon atoms and R.sub.4 is an alicyclic group containing from 5 to 6 carbon atoms,or R.sub.3 and R.sub.4 are two alicyclic groups containing from 5 to 6 carbon atoms,or R.sub.3 and R.sub.4 form, together with the nitrogen atom to which they are chemically linked, a heterocycloaliphatic group.This process is characterized in that a (meth)acrylic anhydride of formula: ##STR2## is reacted with a diamine of formula: ##STR3## in the presence of a polymerization inhibitor.Type: GrantFiled: November 26, 1986Date of Patent: August 22, 1989Assignee: NorsolorInventors: Patrice Hurtel, Denis Laurent
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Patent number: 4795830Abstract: Elevated-temperature decomposition of monoalkylformamides to monoalkylamines and carbon monoxide is inhibited in the presence of small amounts of water.Type: GrantFiled: September 2, 1986Date of Patent: January 3, 1989Assignee: E. I. Du Pont de Nemours and CompanyInventor: Terence A. Rensi
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Patent number: 4692544Abstract: Certain substituted diaryl amines are used to inhibit the polymerization of ethylenically unsaturated monomers; for example, unsaturated carboxylic acids and derivatives thereof.Type: GrantFiled: August 23, 1985Date of Patent: September 8, 1987Assignee: Sandoz Ltd.Inventors: Richard N. Goerner, J. Michael Hipp, Ruth H. Hipp
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Patent number: 4571433Abstract: A process for stabilizing aqueous solutions of acetoacetamides which simultaneously results in the reduction of .beta.-aminocrotonic acid amide content. According to the process, to aqueous acetoacetamide solutions which have been prepared in a known manner by the reaction of diketene with ammonia or water-soluble primary or secondary aliphatic amines under basic conditions, sufficient amounts of diketene are added immediately after their preparation thereto at room temperature with vigorous stirring, to maintain a pH value of 6-7. The so obtained aqueous solutions of the acetoacetamides are not only substantially stable, but also especially pure since these solutions are neither contaminated by salt-like by-products nor by derivatives of .beta.-aminocrotonic acid amides.Type: GrantFiled: September 10, 1984Date of Patent: February 18, 1986Assignee: Wacker-Chemie GmbHInventors: Gerhard Kunstle, Herbert Jung
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Patent number: 4542231Abstract: New and improved compositions are described of ethylenically unsaturated organic compounds capable of addition polymerization stabilized from unintentional or premature polymerization in the liquid phase by the addition of the combination cerium compounds which are soluble in the ethylenically unsaturated organic compounds and phenolic type inhibitors.Type: GrantFiled: July 5, 1983Date of Patent: September 17, 1985Assignee: Celanese CorporationInventors: Edward F. Dougherty, Mark O. Scates
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Patent number: 4474985Abstract: A process for increasing the color-free shelf life of a crude N-acetyl aminophenol prepared by the acetylation of an aminophenol wherein the N-acetyl aminophenol contains color-forming impurities which are the products of oxidation of the aminophenol and other side reactions. The process comprises dissolving the crude N-acetyl aminophenol in a solvent containing a reducing agent, heating the solution at about the boiling point, crystallizing the N-acetyl aminophenol from the solution, washing the crystalline N-acetyl aminophenol with solvent containing reducing agent and thereafter separating and drying the crystalline N-acetyl aminophenol.Type: GrantFiled: January 31, 1983Date of Patent: October 2, 1984Assignee: Monsanto CompanyInventors: Billy L. Keel, Irvin S. Klaus, Marvin L. Oftedahl
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Patent number: 4375558Abstract: Methacrylamidopropyltrimethylammonium chloride or its free amine, dimethylaminopropylmethacrylamide, is purified by contacting aqueous solutions of the salt or the free amine with solid, nonionic organic resins. Such resins absorb the organic impurities, yet leave behind the polymerization inhibitor.Type: GrantFiled: October 9, 1981Date of Patent: March 1, 1983Assignee: Texaco Inc.Inventors: Edward E. McEntire, Edward C. Y. Nieh
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Patent number: 4233240Abstract: Acrylamide aqueous solutions when stored in closed containers without constant supply of oxygen as polymerization inhibitor will polymerize during storage. To extend the safe period of storage under these conditions, cupric ion at concentrations from 0.5 to about 10 parts per million parts acrylamide in the solution is used as a polymerization inhibitor.Type: GrantFiled: February 14, 1977Date of Patent: November 11, 1980Assignee: American Cyanamid CompanyInventors: William F. Linke, William F. Marzluff