Inventor
STEFFENS FRIEDHELM
DE36 patents
⚠️ This page may combine multiple inventors who share the name “STEFFENS FRIEDHELM”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
COVESTRO DEUTSCHLAND AG
15 patentsUS9840461B2Dec 12, 2017
Method for operating a gas-phase phosgenation plant
COVESTRO DEUTSCHLAND AG2 citations72
US10576392B2Mar 3, 2020
Distillation column and use thereof for cleaning isocyanates
COVESTRO DEUTSCHLAND AG1 citations57
US10894222B2Jan 19, 2021
Distributor device, in particular for falling film evaporators, and use thereof
COVESTRO DEUTSCHLAND AG0 citations51
US10676448B2Jun 9, 2020
Method for producing TDI-trimerisates with high purity
COVESTRO DEUTSCHLAND AG0 citations51
US10189945B2Jan 29, 2019
Method for producing light-coloured TDI-polyisocyanates
COVESTRO DEUTSCHLAND AG0 citations51
US11267703B2Mar 8, 2022
Method and a system for separating and treating impurities from a hydrogen chloride liquid mixture
COVESTRO DEUTSCHLAND AG0 citations49
US10889539B2Jan 12, 2021
Aniline purification process
COVESTRO DEUTSCHLAND AG0 citations47
US10011484B1Jul 3, 2018
Process for purifying raw-material gases by fractionation
COVESTRO DEUTSCHLAND AG0 citations47
US9938147B2Apr 10, 2018
Process for purifying raw-material gases by fractionation
COVESTRO DEUTSCHLAND AG0 citations47
US9688619B2Jun 27, 2017
Process for obtaining organic isocyanates from distillation residues from isocyanate preparation
COVESTRO DEUTSCHLAND AG0 citations47
US9376377B2Jun 28, 2016
Method for producing isocyanates
COVESTRO DEUTSCHLAND AG1 citations44
US9845286B2Dec 19, 2017
Process for operating a gas phase phosgenation plant
COVESTRO DEUTSCHLAND AG0 citations41
US10435353B2Oct 8, 2019
Method for producing isocyanates
COVESTRO DEUTSCHLAND AG0 citations40
US10239826B2Mar 26, 2019
Method for producing isocyanates
COVESTRO DEUTSCHLAND AG0 citations38
US12187858B2Jan 7, 2025
Method for recovering raw materials from polyurethane products
COVESTRO DEUTSCHLAND AG0 citations37
BAYER MATERIALSCIENCE AG
9 patentsUS7615662B2Nov 10, 2009
Process for the preparation of isocyanates in the gas phase
BAYER MATERIALSCIENCE AG14 citations84
US7541487B2Jun 2, 2009
Process for the preparation of isocyanates in the gas phase
BAYER MATERIALSCIENCE AG11 citations84
US7645900B2Jan 12, 2010
Process for the preparation of isocyanates
BAYER MATERIALSCIENCE AG7 citations72
US9932299B2Apr 3, 2018
Process for separating an isocyanate prepared by phosgenation of a primary amine in the gas phase from the gaseous crude product of the phosgenation
BAYER MATERIALSCIENCE AG2 citations69
US9480958B2Nov 1, 2016
Device and method for producing phosgene
BAYER MATERIALSCIENCE AG5 citations67
US7511176B2Mar 31, 2009
Process for the preparation of toluenediamines by catalytic hydrogenation of dinitrotoluenes
BAYER MATERIALSCIENCE AG3 citations61
US7322565B2Jan 29, 2008
Stirring device and process for carrying out a gas-liquid reaction
BAYER MATERIALSCIENCE AG3 citations61
US10131641B2Nov 20, 2018
Method for producing TDI-trimerisates with high purity
BAYER MATERIALSCIENCE AG0 citations51
US7575660B2Aug 18, 2009
Process for the distillative separation of aqueous amine solutions
BAYER MATERIALSCIENCE AG1 citations49
BAYER AG
3 patentsUS6719957B2Apr 13, 2004
Process for purification of anhydrous hydrogen chloride gas
BAYER AG89 citations96
US7118653B2Oct 10, 2006
Process for the purification of mixtures of toluenediisocyanate incorporating a dividing-wall distillation column
BAYER AG41 citations90
US4732685AMar 22, 1988
Method of liquid-liquid extraction using material exchange columns
BAYER AG7 citations72
BAYER MATERIALSCIENCE LLC
3 patentsUS8030522B2Oct 4, 2011
Process for the production of toluene diisocyanate
BAYER MATERIALSCIENCE LLC2 citations60
US7555917B2Jul 7, 2009
Process for purification of anhydrous hydrogen chloride gas
BAYER MATERIALSCIENCE LLC1 citations51
US9029595B1May 12, 2015
Method for working up distillation residues from isocyanate production
BAYER MATERIALSCIENCE LLC1 citations50