Patents by Inventor Alfred Krempel

Alfred Krempel 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).

  • Process for the preparation of substituted cycloketones
    Patent number: 6222076
    Abstract: The invention relates to a novel process for the preparation of hydroxyalkyl- and acyloxyalkyl-substituted cycloketones by free-radical addition of hydroxyalkenes and acyloxyalkenes respectively to cyclic ketones.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: April 24, 2001
    Assignee: Haarmann & Reimer GmbH
    Inventors: Alfred Krempel, Oskar Koch, Harry Erfurt
  • Sulphonic acids and their use as UV absorbers
    Patent number: 6042814
    Abstract: Sulphonic acids of formula (I) in which the components and indices have the meanings given in the description, are eminently suitable as u/v absorbers, especially in cosmetic sun-screening agents.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: March 28, 2000
    Assignee: Haarmann & Reimer GmbH
    Inventors: Oskar Koch, Roland Langner, Alfred Krempel
  • Use of benzazoles UV absorbers, new benzazoles and a process for their preparation
    Patent number: 5585091
    Abstract: Compounds which, per molecule, contain at least 2 benzazolyl groups are outstandingly suitable as UV absorbers for sunscreen compositions.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: December 17, 1996
    Assignee: Haarmann & Reimer GmbH
    Inventors: Ralf Pelzer, Roland Langner, Horst Surburg, Horst Sommer, Alfred Krempel, Rudolf Hopp
  • Process for the preparation of pure 2-hydroxybenzyl alcohol, pure 4-hydroxybenzyl alcohol or a mixture of both hydroxy-benzyl alcohols
    Patent number: 4192959
    Abstract: A process for the preparation of pure 2-hydroxybenzyl alcohol, pure 4-hydroxybenzyl alcohol or a mixture of both hydroxybenzyl alcohols by reacting phenol and formaldehyde in the presence of a basic catalyst and subjecting the resulting reaction mixture to an at least 2-stage countercurrent extraction in a solvent system of water/organic solvent which is water-immiscible or water-miscible only to a limited extent.
    Type: Grant
    Filed: June 14, 1978
    Date of Patent: March 11, 1980
    Assignee: Haarmann & Reimer
    Inventors: Kurt Bauer, Alfred Krempel, Reiner Molleken, Karlfried Wedemeyer, Helmut Fiege
  • Selective extraction of glyoxylic acid from aqueous mixture with glyoxal
    Patent number: 4026929
    Abstract: Glyoxylic acid is selectively extracted from its aqueous mixture with glyoxal by means of aliphatic or cycloaliphatic alcohol containing about 4 to 8 carbon atoms, a ketone containing about 4 to 8 carbon atoms, and an ester of an aliphatic carboxylic acid and aliphatic alcohol each containing up to about 6 carbon atoms, the esters containing a total of about 3 to 8 carbon atoms, allowing the mixture to stratify and separating the solvent layer enriched in glyoxylic acid.
    Type: Grant
    Filed: December 29, 1975
    Date of Patent: May 31, 1977
    Assignee: Haarmann & Reimer GmbH
    Inventors: Kurt Bauer, Reiner Molleken, Alfred Krempel