Class / Patent application number | Description | Number of patent applications / Date published |
560344000 | Reactant containing -NH-C(=O)-NH- group (wherein substitution may be made for hydrogen only) | 8 |
20080249332 | Process for the Preparation of Isocyanates - The invention provides a multistage process for continuously preparing organic, distillable polyisocyanates, preferably diisocyanates, more preferably aliphatic or cycloaliphatic diisocyanates, by reacting the corresponding organic polyamines with carbonic acid derivatives and alcohols to low molecular mass monomeric polyurethanes, and thermally cleaving said polyurethanes, in which at defined reaction stages the polyisocyanates prepared and unusable residues are separated off, and reusable by products and intermediates are recycled to upstream stages. | 10-09-2008 |
20090275775 | METHOD FOR PRODUCING ISOCYANATES - The invention relates to a multistage process for the continuous preparation of organic, distillable isocyanates, preferably diisocyanates, particularly preferably aliphatic or cycloaliphatic diisocyanates, by reaction of the corresponding organic amines with urea and alcohols to liberate ammonia and form low molecular weight monomeric urethanes and thermal dissociation of the latter, in which by-products formed are at least partly utilized. | 11-05-2009 |
20100036154 | PROCESS FOR THE CONTINUOUS PREPARATION OF (CYCLO)ALIPHATIC DIISOCYANATES - The invention relates to a multi-stage process for the continuous, phosgene-free preparation of (cyclo)aliphatic diisocyanates that comprises the conversion of (cyclo)aliphatic diamines into the corresponding (cyclo)alkylene biscarbamates and the thermal cleaving of the latter into the (cyclo)alkylene diisocyanates and alcohol. The urea used in accordance with the invention and also the urea employed for the preparation of urea equivalents (e.g. alkyl carbonates, alkyl carbamates) as a possible precursor for the synthesis of the (cyclo)aliphatic biscarbamates is unconditioned. | 02-11-2010 |
20100113823 | ISOCYANATE PRODUCTION PROCESS USING COMPOSITION CONTAINING CARBAMIC ACID ESTER AND AROMATIC HYDROXY COMPOUND, AND COMPOSITION FOR TRANSFER AND STORAGE OF CARBAMIC ACID ESTER - An object of the present invention is to provide an isocyanate production process, which is free of the various problems found in the prior art, and which uses a composition containing a carbamic acid ester and an aromatic hydroxy compound when producing isocyanate without using phosgene, as well as a carbamic acid ester composition for transferring or storing carbamic acid ester. The present invention discloses an isocyanate production process including specific steps and using a composition containing a carbamic acid ester and an aromatic hydroxy compound, as well as a composition for transfer or storage of carbamic acid ester comprising the carbamic acid ester and the specific aromatic hydroxy compound. | 05-06-2010 |
20120172621 | PROCESS FOR PREPARING ISOCYANATES - The invention relates to a multistage process for the continuous preparation of organic, distillable polyisocyanates, preferably diisocyanates, particularly preferably aliphatic or cycloaliphatic diisocyanates, by reaction of the corresponding organic polyamines with carbonic acid derivatives and alcohols to form low molecular weight monomeric polyurethanes and thermal dissociation of the latter, in which the polyisocyanates produced and unusable residues are separated off at particular stages of the reaction and reusable by-products and intermediates are recirculated to preceding stages. | 07-05-2012 |
20130006013 | PROCESS FOR THE PRODUCTION OF POLYISOCYANATES - The invention provides a multistage process for continuously preparing organic polyisocyanates, preferably diisocyanates, more preferably aliphatic or cycloaliphatic diisocyanates, by reaction of the corresponding organic polyamines with carbonic acid derivatives and alcohols into monomeric polyurethanes of low molecular mass, and the dissociation of said polyurethanes. The invention further provides an associated preparation process in which at certain reaction stages the polyisocyanates prepared and unutilizable residues are removed and reusable by-products and intermediates are recycled to preliminary stages. | 01-03-2013 |
20160052874 | METHOD FOR PRODUCING ISOCYANATE - A method for producing an isocyanate, comprising: a carbamation step of generating an N-substituted carbamate from an organic primary amine, urea and an organic hydroxy compound according to a carbamation reaction, and then recovering a first gaseous phase component containing the urea and/or a compound having a carbonyl group derived from the urea, the organic hydroxy compound, and ammonia; a condensation step of condensing the first gaseous phase component with a condenser; an isocyanate production step of producing an isocyanate by subjecting the N-substituted carbamate to pyrolysis; an ammonia absorption step of allowing a second gaseous phase component containing ammonia recovered as a gaseous phase component from the condenser as a main component, to be absorbed by absorption water, and generating gas-absorbed water; and an ammonia stripping step of heating the gas-absorbed water to separate ammonia from the gas-absorbed water. | 02-25-2016 |
20160145201 | METHOD FOR PRODUCING META-XYLYLENEDIISOCYANATES - A method for producing meta-xylylenediisocyanates includes a reaction step in which monohalogenated benzenes, formaldehydes, and an amide compound represented by general formula (1) below are allowed to react in the presence of an acidic liquid to produce a bisamide compound; a dehalogenation step in which in the bisamide compound, the halogen atom derived from the monohalogenated benzenes is replaced with a hydrogen atom; and a thermal decomposition step in which the bisamide compound from which the halogen atom is eliminated is subjected to thermal decomposition. In the reaction step, the acidic liquid contains inorganic acid, the equivalent ratio of the hydrogen atom of the inorganic acid relative to the monohalogenated benzenes is more than 14, the acidic liquid has an inorganic acid concentration of more than 90 mass %, and the reaction temperature is more than 10° C. | 05-26-2016 |