Patents by Inventor Hans Stephan

Hans Stephan 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).

  • Publication number: 20020119549
    Abstract: The present invention relates to polynucleotides corresponding to the rpsL gene and which encode ribosomal protein S12, methods of producing L-amino acids, and methods of screening for polynucleotides which encode proteins having ribosomal protein S12 activity.
    Type: Application
    Filed: October 31, 2001
    Publication date: August 29, 2002
    Applicant: DEGUSSA AG
    Inventors: Bettina Moeckel, Brigitte Bathe, Hans Stephan, Caroline Kreutzer, Thomas Hermann, Walter Pfefferle, Michael Binder
  • Patent number: 5618963
    Abstract: A process is described for the preparation of hydroxybenzylphosphonates of the formula I ##STR1## which involves A) reacting a phenol of the formula II ##STR2## with an amine of the formula III ##STR3## formaldehyde or paraformaldehyde and a protonic acid H.sub.n A to give a salt of the formula IV ##STR4## B) distilling off the water of reaction which forms, and C) reacting the reaction mixture, or the salt IV isolated therefrom, with a trialkyl phosphite of the formula ##STR5## in which H.sub.n A is an organic or inorganic acid having n protons,n is 1, 2, 3 or 4,R.sub.1 and R.sub.2 independently of one another are C.sub.1 -C.sub.12 alkyl or C.sub.5 -C.sub.7 cycloalkyl,R.sub.3 and R.sub.4 independently of one another are C.sub.1 -C.sub.12 alkyl or form, together with the nitrogen atom attached to them, a piperidyl or morpholinyl radical, and R.sub.5, R.sub.6 and R.sub.7 independently of one another are C.sub.1 -C.sub.
    Type: Grant
    Filed: June 22, 1995
    Date of Patent: April 8, 1997
    Assignee: Ciba-Geigy Corporation
    Inventors: Thomas Engert, Hans Stephan, Walter Wolf
  • Patent number: 4731448
    Abstract: There is disclosed a process for the preparation of 1-(2-hydroxyethyl-2,2,6,6-tetramethyl-4-piperidinol from triacetoneamine, which comprises first reducing triacetoneamine in water and/or a polar organic solvent by catalytic hydrogenation to 2,2,6,6-tetramethyl-4-piperidinol, and adding a catalytic amount of acid to the resultant solution, without isolation of the intermediate, after optional concentration of the solution by distillation, and subsequently reacting the 2,2,6,6-tetramethyl-4-piperidinol with ethylene oxide.1-(2-Hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol is a useful light and heat stabilizer for plastics and is, in addition, a valuable intermediate for the synthesis of further light stabilizer additives.
    Type: Grant
    Filed: December 3, 1986
    Date of Patent: March 15, 1988
    Assignee: Ciba-Geigy Corporation
    Inventors: Heinz Issler, Siegfried Kintopf, Lutz Konig, Hans Stephan
  • Patent number: 4554368
    Abstract: A process for the production of alkyltin thiocarboxylic acid esters from alkyltin halides and thiocarboxylic acid esters in the presence of an acid acceptor, which process comprises carrying out the reaction continuously in a reaction system comprising 1 to 5 agitator vessels with an average dwell time of 1 to 60 minutes, at a constant pH value in the range from 3 to 8, and in a temperature range from 40.degree. to 80.degree. C. and separating the product drawn off from the reaction system from the aqueous phase and subsequently drying it.The alkyltin thiocarboxylic acid esters obtained by the process of the invention are used for stabilizing homo- and copolymers of vinyl chloride.
    Type: Grant
    Filed: December 1, 1982
    Date of Patent: November 19, 1985
    Assignee: Ciba-Geigy Corporation
    Inventors: Rudolf Maul, Hans Stephan, Walter Wolf