Patents by Inventor Harro Schlesmann

Harro Schlesmann 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: 5719294
    Abstract: The preparation of N-cyclohexylthiophthalimide from cyclohexylsulphenyl chloride and phthalimide can be reproduced more reliably if the cyclohexylsulphenyl chloride is prepared in sire by chlorinating dicyclohexyl disulphide.
    Type: Grant
    Filed: November 13, 1996
    Date of Patent: February 17, 1998
    Assignee: Bayer AG
    Inventors: Adolf Sicheneder, Wilfried Nolte, Harro Schlesmann, Thomas Kleiner
  • Patent number: 5286870
    Abstract: Bis-benzthiazolyl alkyl sulfenimides are produced by a process in which alkyl amines are reacted with optionally substituted 2-mercaptobenzthiazoles in the presence of oxygen or oxygen-containing gases and copper and/or copper compounds and in the presence of inert organic solvents.
    Type: Grant
    Filed: August 17, 1992
    Date of Patent: February 15, 1994
    Assignee: Bayer AG
    Inventors: Adolf Sicheneder, Harro Schlesmann
  • Patent number: 5198550
    Abstract: Crude 2-mercaptobenzothiazole is purified by a process in which the crude 2-mercaptobenzothiazole is dissolved in relatively high-boiling aliphatic or cycloaliphatic alcohols or in mixtures of the alcohols mentioned or azeotropes thereof with water at temperatures of 60.degree. to 200.degree. C., optionally under elevated pressure, or is suspended in relatively high-boiling aliphatic or cycloaliphatic alcohols, aliphatic or cycloaliphatic ethers, organic acids or esters thereof at temperatures of 10.degree. to 100.degree. C., the solution or suspension is subsequently cooled and the product precipitating is filtered off and optionally washed.
    Type: Grant
    Filed: June 1, 1992
    Date of Patent: March 30, 1993
    Assignee: Bayer Aktiengesellschaft
    Inventors: Klaus Reinartz, Harro Schlesmann, Stefan Dietl
  • Patent number: 4771067
    Abstract: 4-nitrodiphenylamines may be produced by an improved process from 4-halo nitrobenzenes and primary aromatic amines in the presence of potassium carbonate and copper compounds, wherein(1) mono- and di-carboxylic acid amides or nitriles are added;(2) from 3 to 5 mol of amine are introduced per mol of halo nitrobenzene; and(3) from 1.2 to 2 mol of the amine are added prior to the reaction and the remainder during the reaction so that the molar excess of amine relative to halo nitrobenzene is always from 100 to 400%.
    Type: Grant
    Filed: August 26, 1987
    Date of Patent: September 13, 1988
    Assignee: Bayer Aktiengesellschaft
    Inventors: Chiraranjan Podder, Harro Schlesmann
  • Patent number: 4670595
    Abstract: The reaction of 4-nitrohalogenbenzenes with primary aromatic amines in the presence of potassium carbonate and copper compounds to 4-nitrodiphenylamines gives better yield of purer products when synthetic polyamides are added.
    Type: Grant
    Filed: February 3, 1986
    Date of Patent: June 2, 1987
    Assignee: Bayer Aktiengesellschaft
    Inventors: Chiraranjan Podder, Harro Schlesmann
  • Patent number: 4665232
    Abstract: The reaction of 4-nitrohalobenzenes with primary aromatic amines in the presence of potassium carbonate and copper compounds to produce 4-nitrodiphenylamine results in products with improved purity and yield if (1) carbonic acid amides or their derivatives are added, (2) 3 to 5 mol of amine are used per mole of halonitrobenzene and (3) 1.2 to 2 mol of the amine are added before the beginning of the reaction and the remainder during the reaction at such a rate that the molar excessive amine over halonitrobenzene is always from 100 to 400%.
    Type: Grant
    Filed: January 9, 1986
    Date of Patent: May 12, 1987
    Assignee: Bayer Aktiengesellschaft
    Inventors: Chiraranjan Podder, Harro Schlesmann
  • Patent number: 4665233
    Abstract: An improved process for the preparation of 4-nitrodiphenylamines by the reaction of 4-nitrohalobenzenes with primary aromatic amines in the presence of potassium carbonate and copper compounds is characterized in that sulpholane dimethylsulphone, dimethylacetamide, diethylacetamide, tetramethylurea, tetraethylurea or mixtures thereof are used as solvents and 3 to 5 mol of amine are used per mol of halogenated nitrobenzene, from 1.2 to 2 mol of said amine being added before the beginning of the reaction and the remainder during the reaction at such a rate that the molar excess of unreacted amine over unreacted halogenated nitrobenzene is constantly at least 100%.
    Type: Grant
    Filed: November 18, 1985
    Date of Patent: May 12, 1987
    Assignee: Bayer Aktiengesellschaft
    Inventors: Chiraranjan Podder, Harro Schlesmann