Patents by Inventor Klaus Nachtkamp

Klaus Nachtkamp has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8722092
    Abstract: The present invention provides novel nanoscale cellulose particles and also a process for their production. The cellulose-based particles obtained have volume-averaged particle sizes of less than 300 nm. These nanoparticles are produced from amorphous cellulose or by amorphization of cellulose, optional subsequent hydrolysis and by input of energy into a water-containing medium after or during dispersion.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: May 13, 2014
    Assignee: Dow Global Technologies LLC
    Inventors: Klaus Nachtkamp, Jürgen Engelhardt, Christa Krüger, Steffen Fischer, Manfred Pinnow, Kay Hettrich
  • Patent number: 8338494
    Abstract: The present invention provides novel nanoscale cellulose particles and also a process for their production. The cellulose-based particles obtained have volume-averaged particle sizes of less than 300 run. These nanoparticles are produced from slightly oxidized cellulose and by input of energy into a water-containing medium after or during dispersion.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: December 25, 2012
    Assignee: Dow Global Technologies LLC
    Inventors: Klaus Nachtkamp, Christa Krüger, Jürgen Engelhardt, Volker Kriegisch, Steffen Fischer, Manfred Pinnow, Kay Hettrich
  • Patent number: 8182839
    Abstract: The present invention relates to novel nanoparticles based on cellulose and a process for producing them and their use.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: May 22, 2012
    Assignee: Dow Global Technologies LLC
    Inventors: Jurgen Engelhardt, Birgit Kosan, Christa Maria Kruger, Frank Meister, Klaus Nachtkamp, Jens Schaller
  • Publication number: 20110293732
    Abstract: The present invention provides novel nanoscale cellulose particles and also a process for their production. The cellulose-based particles obtained have volume -averaged particle sizes of less than 300 nm. These nanoparticles are produced from amorphous cellulose or by amorphization of cellulose, optional subsequent hydrolysis and by input of energy into a water-containing medium after or during dispersion.
    Type: Application
    Filed: August 8, 2008
    Publication date: December 1, 2011
    Inventors: Klaus Nachtkamp, Jürgen Engelhardt, Christa Krüger, Steffen Fischer, Manfred Pinnow, Kay Hettrich
  • Publication number: 20110198533
    Abstract: The present invention provides novel nanoscale cellulose particles and also a process for their production. The cellulose-based particles obtained have volume-averaged particle sizes of less than 300 run. These nanoparticles are produced from slightly oxidized cellulose and by input of energy into a water-containing medium after or during dispersion.
    Type: Application
    Filed: August 8, 2008
    Publication date: August 18, 2011
    Inventors: Klaus Nachtkamp, Christa Krüger, Jürgen Engelhardt, Volker Kriegisch, Steffen Fischer, Manfred Pinnow, Kay Hettrich
  • Publication number: 20100272819
    Abstract: The present invention relates to novel nanoparticles based on cellulose and a process for producing them and their use.
    Type: Application
    Filed: November 29, 2007
    Publication date: October 28, 2010
    Inventors: Jurgen Engelhardt, Birgit Kosan, Christa Maria Kruger, Frank Meister, Klaus Nachtkamp, Jens Schaller
  • Patent number: 7071326
    Abstract: An anionic cellulose nitrate derivative is described, which has: (i) a degree of acid group substitution (DS (acid)) in the range of 0.01 to 0.2; and (ii) a nitrogen content of 10.7 wt. % to 12.3 wt. %, based on the weight of cellulose nitrate derivative. The anionic cellulose nitrate derivative is prepared by a process which includes esterifying cellulose nitrate feed material with at least one dicarboxylic acid anhydride (e.g., maleic anhydride). Aqueous dispersions according to the present invention include: (a) at least on anionic cellulose nitrate derivative according to the present invention; and (b) at least one base.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: July 4, 2006
    Assignee: Wolff Cellulosics GmbH & Co. KG
    Inventors: Carsten Hüttermann, Thomas Wagner, Klaus Nachtkamp
  • Publication number: 20060117998
    Abstract: An anionic cellulose nitrate derivative is described, which has: (i) a degree of acid group substitution (DS (acid)) in the range of 0.01 to 0.2; and (ii) a nitrogen content of 10.7 wt. % to 12.3 wt. %, based on the weight of cellulose nitrate derivative. The anionic cellulose nitrate derivative is prepared by a process which includes esterifying cellulose nitrate feed material with at least one dicarboxylic acid anhydride (e.g., maleic anhydride). Aqueous dispersions according to the present invention include: (a) at least on anionic cellulose nitrate derivative according to the present invention; and (b) at least one base.
    Type: Application
    Filed: November 30, 2005
    Publication date: June 8, 2006
    Inventors: Carsten Huttermann, Thomas Wagner, Klaus Nachtkamp
  • Publication number: 20060041117
    Abstract: A process is described for the preparation of cellulose derivatives containing amino groups that involves reacting, in the presents of water as a reaction medium, alkali cellulose or alkali cellulose derivatives with reagents represented by the following formula, X—(CH2)n—NR1R2 in which: X is selected from the group consisting of chlorine, bromine, iodine and a sulfonic acid radical R?SO3, in which R? is an aromatic radical or an aliphatic radical; n is at least 2; and R1 and R2 independently of each other are selected from the group consisting of aliphatic substituents, branched alkyl substituents, cyclic alkyl substituents, aryl substituents, aryl substituents substituted by heteroatoms, H, and R1 and R2 together form a ring with the nitrogen. In the process, the mole ratio of cellulose to water, of said reaction medium, is 1:5 to 1:40 mol water per mol of anhydroglucose unit (AGU).
    Type: Application
    Filed: July 19, 2005
    Publication date: February 23, 2006
    Inventors: Jurgen Engelhardt, Meinolf Brackhagen, Klaus Nachtkamp, Wolfgang Koch, Thomas Schulze, Frank Meister
  • Patent number: 6509396
    Abstract: An oil-in-water coating agent is described. The coating agent emulsion is prepared from a composition comprising: a) 5.0 to 50 wt. % of cellulose substance; b) 5.0 to 50 wt. % of at least one hydroxyl group-containing lacquer resin; c) 2.0 to 25 wt. % of at least one polyisocyanate having more than one free isocyanate group; d) 10.0 to 65 wt. % of water; e) 0.5 to 30 wt. % of plasticiser; f) 0.0 to 20 wt. % of emulsifier; and g) 0.0 to 45 wt. % of at least one organic solvent. The sum of components a) to g) of the composition is 100 wt. %, and the weight ratio of hydroxyl groups of the hydroxyl group-containing lacquer resin b) to NCO groups of the polyisocyanate c) is 1:0.05 to 1:5. Also described is a method of using the coating agent emulsion, and its application to the surface of materials, such as wood and metal.
    Type: Grant
    Filed: July 26, 2000
    Date of Patent: January 21, 2003
    Assignee: Wolff Walsrode AG
    Inventors: Lutz Hoppe, Hans-Günter Poersch-Panke, Klaus Nachtkamp
  • Patent number: 6005046
    Abstract: This invention relates to polyisocyanates which are partially or completely blocked with 3,5-dimethyl-1,2,4-triazole, to heat curable, one-component coating compositions containing these blocked polyisocyanates and to the resulting coatings.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: December 21, 1999
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gerald Kurek, Eberhard Konig, Klaus Nachtkamp, Theodor Engbert
  • Patent number: 5981653
    Abstract: The present invention relates to a process for the production of aqueous dispersions which form powder coatings at room temperature, have an average particle size of 0.1 to 10 .mu.m, contain polyols and blocked polyisocyanate crosslinking agents, and, after stoving, yield coatings with improved water and solvent resistance, in particular on metallic substrates.
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: November 9, 1999
    Assignee: Bayer Aktiengesellschaft
    Inventors: Oswald Wilmes, Lothar Kahl, Bernd Klinksiek, Christian Wamprecht, Manfred Bock, Klaus Nachtkamp
  • Patent number: 5900510
    Abstract: Diaminodipropyl ethers and hydroxyaminodipropyl ethers are prepared by catalytic amination of dipropylene glycol.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: May 4, 1999
    Assignee: Bayer Aktiengesellschaft
    Inventors: Helmut Waldmann, Klaus Nachtkamp, Josef Pedain, Anatoly Bazanov, Alexandre Timofeev, Natalja Zubritskaya, Gennady Terechtchenko
  • Patent number: 5889106
    Abstract: This invention relates to polyisocyanates which are partially or completely blocked with 3,5-dimethyl-1,2,4-triazole, to heat curable, one-component coating compositions containing these blocked polyisocyanates and to the resulting coatings.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: March 30, 1999
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gerald Kurek, Eberhard Konig, Klaus Nachtkamp, Theodor Engbert
  • Patent number: 5852106
    Abstract: The present invention relates to aqueous polyurethane coating compositions wherein the binder containsa) a polyol component, which is soluble or dispersible in water and is the reaction product of a polyisocyanate component containing 50 to 100 wt. % of 4,4'-diisocyanatodicyclohexylmethane, a polyol component containing one or more polyether polyols and having an OH number of 25 to 350 mg KOH/g solids and an isocyanate-reactive component containing at least one group capable of salt formation andb) a polyisocyanate component, which is soluble or dispersible in water, has blocked isocyanate groups and is the reaction product of a polyisocyanate having an isocyanurate group content of 2 to 30 wt.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: December 22, 1998
    Assignee: Bayer Aktiengesselschaft
    Inventors: Oswald Wilmes, Beate Baumbach, Klaus Nachtkamp, Eberhard Konig, Randall Dearth, Manfred Bock, Wolfhart Wieczorrek
  • Patent number: 5804647
    Abstract: The present invention relates to aqueous polyurethane-urea dispersions which are film forming at temperatures of .ltoreq.20.degree. C. in the absence of film forming additives, dry at room temperature to yield films having a hardness according to DIN 53 157 (Konig pendulum hardness) of .gtoreq.100 seconds, in which the polyurethane-ureas have a urethane group content (calculated as --NH--CO--O--, molecular weight 59) of 7 to 20 wt. %, and a urea group content (calculated as -NH-CO-N, molecular weight 57) of 5 to 18 wt. %, and contain 15-70 wt. %, based on resin solids, of structural units prepared by incorporating 1-methyl-2,4- and/or -2,6-diisocyanatocyclohexane in the form of urethane and/or urea groups. The present invention also relates to a process for the production of these aqueous polyurethane-urea dispersions and to their use in coating compositions.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: September 8, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Klaus Nachtkamp, Oswald Wilmes, Eberhard Arning, Rolf Roschu
  • Patent number: 5789620
    Abstract: The present invention relates to a process for preparing 1,4-bis(aminomethyl)cyclohexane by reacting a 40 to 80 wt. % aqueous solution of 1,4-bis(hydroxymethyl)cyclohexane with a mixture of hydrogen and ammonia in the presence of a nickel/copper/chromium catalyst at a pressure of 100 to 250 bar and a temperature of 150.degree. to 250.degree. C.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: August 4, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Helmut Waldmann, Jurgen Dahmer, Klaus Nachtkamp, Anatoly Bazanov, Alexandre Timofeev, Natalja Zubritskaya, Gennady Terechtchenko
  • Patent number: 5747628
    Abstract: Polyisocyanates based on polyhydroxy polyethers and tolylene diisocyanate containing ether and urethane groups and having an isocyanate group content of from 11.8 to 14.4% by weight, an average isocyanate functionality of from 3.1 to 4.0 and a free tolylene diisocyanate content of less than 0.1% by weight are produced by reacting a polyhydroxy polyether having a molecular weight in the range of from about 350 to about 500 with excess quantities of tolylene diisocyanate and subsequently distilling the mixture to remove unreacted excess of the starting diisocyanate. These polyisocyanates are particularly useful in the production of polyurethane lacquers.
    Type: Grant
    Filed: December 2, 1992
    Date of Patent: May 5, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Lutz Schmalstieg, Hermann Gruber, Bernd Riberi, Klaus Nachtkamp
  • Patent number: 5747582
    Abstract: The invention relates to coating compositions used to prepare coatings having water vapor permeabilities of at least 2500 g/m.sup.2 per day (DS 2109 TM1 method) containing(A) a polyurethane containing (1) 0.1 to 75 meq/100 g of ionic groups and (2) 11 to 50% by weight of --(CH.sub.2 CH.sub.2 O).sub.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: May 5, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Detlef-Ingo Schutze, Wilhelm Thoma, Klaus Nachtkamp, Josef Pedain, Reinold Schmitz
  • Patent number: 5744633
    Abstract: A new process for the production of high purity (cyclo)aliphatic diurethanes from (cyclo)aliphatic diamines, alcohols and urea in a multistep reaction in which (1) urea is reacted with alcohol with elimination of ammonia, (2) diamine is then introduced into the reaction mixture, optionally in the form of a solution in alcohol, and reacted with continuous release of ammonia and (3) the reaction mixture is freed from volatile components by distillation. The diurethanes produced by this process are useful as starting materials for the production of the corresponding diisocyanates by thermal urethane cleavage.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: April 28, 1998
    Assignee: Bayer Aktiengesellschaft
    Inventors: Oswald Wilmes, Eberhard Konig, Klaus Nachtkamp, Ernst Kysela