Biurets (i.e., Hnh-co-nh-co-hnh, Wherein Substitution May Be Made For Hydrogen Only) Patents (Class 564/38)
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Patent number: 4731415Abstract: A polyisocyanate having a biuret structure obtained by allowing .alpha.,.alpha.,.alpha.',.alpha.'-tetramethyl-xylylene diisocyanate, a diisocyanate represented by the general formula:OCN--CH.sub.2 --R--CH.sub.2 --NCOwherein R is a divalent hydrocarbon residue and water to react.The polyisocyanate is used in the form of the two-part type of polyurethane composition in combination with a polyol.The composition can provide coating films which excel in every physical properties required for the coating film, such as drying property, impact resistance, weathering resistance and chemical resistance, and therefore are advantageously used, for example, as a paint for automobile repairing uses, etc.Type: GrantFiled: April 2, 1986Date of Patent: March 15, 1988Assignee: Takeda Chemical Industries, Ltd.Inventors: Shoichi Fujita, Kohji Nasu
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Patent number: 4701555Abstract: The biuret content of biuret-containing urea is reduced by contacting a solution or melt of biuret-containing urea with a polar adsorbent under conditions sufficient to remove at least a portion of biuret from the urea. The resulting biuret-containing adsorbent can be regenerated for further use by contact with a polar desorbent under conditions sufficient to desorb at least a portion of the biuret contained on the adsorbent. Optionally, biuret can be recovered by recovering the biuret-containing desorbent, and biuret concentration in the desorbent can be increased by recycling the biuret-containing desorbent into contact with biuret-containing adsorbents, and biuret can be recovered from the desorbent by low temperature crystallization.Type: GrantFiled: July 10, 1985Date of Patent: October 20, 1987Assignee: Union Oil Company of CaliforniaInventors: Donald C. Young, James A. Green, II
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Patent number: 4698443Abstract: Purified biuret is recovered from mixtures containing biuret and higher molecular weight urea condensation products by contacting melts or solutions of such mixtures with a polar adsorbent and extracting biuret from the adsorbent with a polar desorbent. The useful biuret-containing mixtures also may contain urea. These methods are capable of recovering biuret of 99.9 percent plus purity from mixture containing higher molecular weight urea condensations products such as triuret, melamine, ammelide, and others. The biuret-containing desorbent can be recycled into contact with biuret-containing adsorbents to increase its biuret concentration, concentrated by evaporation of otherwise, and/or treated to crystallize biuret. An integrated process is provided which involves pyrolyzing urea to form biuret and higher molecular weight condensation products and selectively recovering biuret from the resulting pyrolyzed urea as described.Type: GrantFiled: July 10, 1985Date of Patent: October 6, 1987Assignee: Union Oil Company of CaliforniaInventors: Donald C. Young, James A. Green, II
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Patent number: 4684746Abstract: Improved activators for anionic polymerization of lactams are biuret-containing polyisocyanates based on non-aromatic diisocyanates.Type: GrantFiled: July 1, 1985Date of Patent: August 4, 1987Assignee: Bayer AktiengesellschaftInventors: Rolf-Volker Meyer, Friedrich Fahnler, Rolf Dhein, Dietrich Michael
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Patent number: 4654441Abstract: Process for the production of technical grade biuret, readily in a form suitable for use as animal feed, by the controlled pyrolysis of urea in two stages, the first stage involving the partial pyrolysis of urea at a temperature above the melting point of urea to produce a first stage intermediate reaction product containing from about 20% to about 60% urea, and not more than about 25% cyanuric acid by weight, such reaction product being then cooled and comminuted, the comminuted product then being subjected, in solid form and in the absence of a liquid carrier, to a temperature at or slightly below the softening point of the solid particulate (suitable at a temperature of from about 100.degree. C. to about 140.degree. C.) with forced air circulation through the comminuted product for a sufficient time to lower its urea content by partial sublimation of the urea and partial further reaction thereof to biuret with only minimal further conversion of urea to cyanuric acid.Type: GrantFiled: May 20, 1981Date of Patent: March 31, 1987Assignee: Moorman Manufacturing CompanyInventors: Kurt F. Stephan, John T. Stephan, Steven R. Klein
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Patent number: 4645859Abstract: Methods are provided for recovering purified biuret from aqueous solutions containing biuret and higher molecular weight urea condensation products by contacting such solutions with the hydroxide ion form of an anion exchanger and extracting biuret from the ion exchanger with an aqueous extractant. The useful biuret-containing solutions also may contain urea. These methods are capable of recovering biuret of 99.9 percent plus purity from solutions containing higher molecular weight urea condensations products such as triuret, melamine, ammelide, and others. Elevated temperatures increase biuret recovery rate and concentration, and the extractant can be recycled into contact with additional biuret-containing anion exchangers to increase biuret concentration even further. The biuret-containing extract can be employed as is, concentrated by evaporation or otherwise, or treated to crystallize biuret.Type: GrantFiled: April 19, 1985Date of Patent: February 24, 1987Assignee: Union Oil Company of CaliforniaInventors: James A. Green, II, Donald C. Young
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Patent number: 4625052Abstract: The present invention is directed to a process for the production of polyisocyanates which have a biuret structure by reacting aliphatic diisocyanates with water at elevated temperature, characterized in that the reaction is carried out in the presence of:(a) .alpha., .alpha., .alpha.-tri-substituted acetic acids, which do not have any further isocyanate-reactive group other than the carboxyl group,and/or(b) anhydrides of acids of the type mentioned in (a)wherein up to 0.39 mols of component (a) are used per mol of water, up to about 2 mols of component (b) are used per mol of water, and the total quantity of components (a) and (b) is at least 0.02 to about 2 mols per mol of water.Type: GrantFiled: January 25, 1985Date of Patent: November 25, 1986Assignee: Bayer AktiengesellschaftInventors: Klaus Konig, Josef Pedain, Helmut Woynar
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Patent number: 4613686Abstract: The present invention relates to a process for the preparation of polyisocyanates which have a biuret structure of reacting excess quantities of aliphatic diisocyanates with biuretizing agents at elevated temperature, characterized in that the biuretizing agent contains(a) .alpha.,.alpha.,.alpha.-trisubstituted acetic acids which do not contain isocyanate-reactive groups apart from the carboxyl group, and optionally(b) water,wherein the molar ratio of biuretizing components (a) to (b) is within the range of from 1:0 to 1:2.5.Type: GrantFiled: January 25, 1985Date of Patent: September 23, 1986Assignee: Bayer AktiengesellschaftInventors: Klaus Konig, Josef Pedain, Helmut Woynar
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Patent number: 4560738Abstract: A novel pest-combating agent of increased duration of action is produced by reacting a pest-combating agent having at least one hydrogen atom active in a Zerewitinoff reaction other than a hydrogen atom which is part of a carbamic acid ester group ##STR1## with a polyether isocyanate, the reaction with the polyether isocyanate taking place on said other hydrogen atom.Type: GrantFiled: August 19, 1983Date of Patent: December 24, 1985Assignee: Bayer AktiengesellschaftInventors: Roland Richter, Paul Reinecke, Hanns P. Muller, Gerhard Bonse, Wilhelm Brandes
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Patent number: 4540820Abstract: Preparation of a composition particularly suitable for use as feedstock in the production of animal feed grade biuret by solid state pyrolyzation thereof in a recirculating oven, which composition comprises from about 37% to about 25% urea, from about 45% to about 60% biuret, and from about 3% to about 20% cyanuric acid, by weight, such preparation involving sparging air or other non-reactive gas through a urea charge at a temperature of from about 145.degree. C. to about 165.degree. C. and at a rate of between about two to about ten cu. ft. of gas/hr/lb of urea for a period of at least four hours, then cooling and comminuting the product.Type: GrantFiled: January 3, 1983Date of Patent: September 10, 1985Assignee: Moorman Manufacturing CompanyInventors: Kurt F. Stephan, John T. Stephan
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Patent number: 4532317Abstract: Aromatic polyamines containing aromatic primary amino groups as well as urethane and polyester groups are made by hydrolyzing an isocyanate in the presence of a basic material and water to form a carbamate and then converting the carbamate groups to amino groups. The isocyanate starting material contains aromatic isocyanate groups (as well as urethane and polyester groups) and has an NCO content of from 0.5 to 11.5 wt %. The basic compound is selected from alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal silicates, alkali metal sulfides, alkali metal cyanides, tetraalkylammonium hydroxides and mixtures thereof. Water is used in a quantity such that at least one mole of water is present for each equivalent of NCO groups. The carbamate groups may be converted to amino groups by treating the carbamate-containing mixture with a proton donor or with heat or with a solvent. The product polyamines are particularly useful in the production of polyurethanes.Type: GrantFiled: June 21, 1983Date of Patent: July 30, 1985Assignee: Bayer AktiengesellschaftInventor: Werner Rasshofer
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Patent number: 4532266Abstract: Polyether-based urethane-group-containing polyamines containing polymers and/or copolymers of unsaturated monomers and, optionally, urea and/or biuret and/or allophanate groups are produced by (a) reacting an NCO-prepolymer in aqueous alkaline solution at 0.degree. to 40.degree. C. to form a carbamate; (b) converting this carbamate to an amine by adding an ion exchanger to the reaction mixture; and (c) separating the polyamine from the reaction mixture. The NCO-prepolymers used as starting materials are prepolymers of (i) polyalkylene ether polyols having a molecular weight of from 1,000 to 10,000 containing from 1 to 60 wt. % of graft (co)polymers of unsaturated monomers; and (ii) excess molar quantities of organic polyisocyanate; and optionally, (iii) a low molecular weight chain-extending agent. The product polyamines have a molecular weight of from 1,000 to 10,000 and contain from 0.65 to 59.3 wt. % graft (co)polymer and from 0.11 to 2.9 wt. % terminal NH.sub.Type: GrantFiled: March 19, 1982Date of Patent: July 30, 1985Assignee: Bayer AktiengesellschaftInventors: Werner Rasshofer, Gerhard Balle, Dieter Dieterich, Holger Meyborg
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Patent number: 4525590Abstract: The invention relates to an improved process for the production of polyamines containing urethane and/or urea and/or biuret and/or isocyanurate groups and, preferably, also alkylene ether, carbonate and/or acetal groups by the alkaline hydrolysis of corresponding compounds containing terminal aliphatic and/or aromatic isocyanate groups.To this end, the compounds containing terminal NCO-groups, preferably NCO-preadducts, are converted by means of selected bases into the carbamates and neutralized by introduction into equivalent quantities of acid or by the simultaneous introduction of the components in equivalent quantities into a reaction vessel, after which the polyamines are directly isolated by methods known per se.The invention also relates to the use of the polyamines obtained by the process for the production of polyurethanes.Type: GrantFiled: July 15, 1982Date of Patent: June 25, 1985Assignee: Bayer AktiengesellschaftInventors: Werner Rasshofer, Klaus Konig, Holger Meyborg, Walter Meckel, Armin Zenner
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Patent number: 4472568Abstract: This invention relates to an improved process for the preparation of aromatic polyamines containing urethane and/or biuret and/or urea and/or isocyanurate groups and preferably also ether groups by the hydrolysis of poly-N-monoaryl-N',N'-dialkyl urea compounds (1-aryl-3,3-dialkyl ureas). The ureas are obtained by the reaction of secondary aliphatic, cycloaliphatic or saturated heterocyclic amines with divalent to tetravalent isocyanate compounds containing isocyanate end groups attached to aromatic residues. The ureas correspond to the general formula: ##STR1## wherein R.sup.1, R.sup.2 denote alkyl or cycloalkyl groups, or together form a ring andA denotes a divalent to tetravalent residue attached to the ureas by aromatic groups.Hydrolysis is carried out in the presence of water and up to two equivalents of a base containing hydroxide ions and/or up to two equivalents of a compound containing tertiary amino groups, optionally in the presence of solvents.Type: GrantFiled: October 28, 1982Date of Patent: September 18, 1984Assignee: Bayer AktiengesellschaftInventors: Werner Rasshofer, Gerhard Grogler
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Patent number: 4386218Abstract: A compound having a terminal isocyanate group is hydrolyzed to produce a polyamine having a urethane and/or a urea and/or a biuret group. More particularly, a carbamate is made by mixing an isocyanate prepolymer having urethane and/or urea and/or biuret groups present with aqueous base solutions at a temperature of from 0.degree. to 0.degree. C. and in quantities such that the equivalent ratio of hydroxyl to isocyanate groups is between from 0.3:1 to .gtoreq.1.01 to 1. The carbamate is then treated with an acid ion exchanger to form an amine. The amine is then removed from any other material which may be present. A preferred polyamine thus-produced corresponds to the general formula: ##STR1## in which each R radical may represent a divalent straight or branched-chain aliphatic radical; a divalent cycloaliphatic radical; a 4,4'- and/or a 2,4'-dicyclohexylmethane radical; or a 2,4- and/or 2,6-methyl cyclohexane radical.Type: GrantFiled: October 5, 1981Date of Patent: May 31, 1983Assignee: Bayer AktiengesellschaftInventors: Werner Rasshofer, Dieter Dieterich, Holger Meyborg
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Patent number: 4382956Abstract: N-Sulphenylated biurets of the formula ##STR1## in which R.sup.1 represents a trihalogenomethyl radical,R.sup.2 represents an optionally substituted aliphatic, cycloaliphatic, araliphatic or aromatic radical andR.sup.3 and R.sup.4 are identical or different and represent a hydrogen atom, an optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radical or the amino or hydroxyl group, or together with the connecting nitrogen atom represent a five-membered or six-membered heterocyclic ring, the ring carbon atoms of which are optionally interrupted by one or more further hetero-atoms,which possess fungicidal activity.Type: GrantFiled: December 15, 1981Date of Patent: May 10, 1983Assignee: Bayer AktiengesellschaftInventors: Engelbert Kuhle, Volker Paul, Wilhelm Brandes
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Patent number: 4344893Abstract: Novel compounds are described which are substituted benzophenone hydrazones. They have pesticidal activity, especially against insects and acarids, and pesticidal compositions and methods are described. Methods of making the compounds, and novel intermediates, are also described.Type: GrantFiled: February 25, 1980Date of Patent: August 17, 1982Assignee: The Boots Company LimitedInventors: Leonard G. Copping, John C. Kerry, Thomas I. Watkins, Robert J. Willis, Bryan H. Palmer
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Patent number: 4331680Abstract: Novel compounds are described which are substituted benzophenone hydrazones. They have pesticidal activity, especially against insects and acarids, and pesticidal compositions and methods are described. Methods of making the compounds, and novel intermediates, are also described.Type: GrantFiled: August 25, 1980Date of Patent: May 25, 1982Assignee: The Boots CompanyInventors: David P. Giles, John C. Kerry, Antonin Kozlik, Bryan H. Palmer, Stephen W. Shutler, Robert J. Willis
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Patent number: 4293713Abstract: A novel 1,1,3,5-substituted biuret compound of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are respectively the same or different, and each are alkyl groups having 1 to 4 carbon atoms; R.sup.3 is a cyclohexyl group or a phenyl group which may be unsubstituted or may have at least one substituent selected from the group consisting of chlorine, bromine, fluorine, methyl, trifluoromethyl, dimethylamino, methoxy, methylthio, nitro and acetyl. The novel 1,1,3,5-substituted biuret compounds are useful as an analgesic, anti-inflammatory and/or anti-pyretic agent.Type: GrantFiled: March 27, 1980Date of Patent: October 6, 1981Assignee: Taiho Pharmaceutical Company LimitedInventors: Hajime Fujimura, Yasuzo Hiramatsu, Takahiro Yabuuchi, Masakatu Hisaki, Katsuo Takikawa, Takaji Honna, Hidekazu Miyake, Makoto Kajitani