Haarmann & Reimer Gmbh

Alfred Krempel

Oskar Koch

Kurt Bauer

Roland Langner

Reiner Molleken

Helmut Fiege

Karlfried Wedemeyer

Horst Surburg

Rudolf Hopp

Harry Erfurt

Horst Sommer

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.

Process for the preparation of substituted cycloketones

Sulphonic acids and their use as UV absorbers

Compounds which, per molecule, contain at least 2 benzazolyl groups are outstandingly suitable as UV absorbers for sunscreen compositions.

Use of benzazoles UV absorbers, new benzazoles and a process for their

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.

Process for the preparation of pure 2-hydroxybenzyl alcohol, pure

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.

Selective extraction of glyoxylic acid from aqueous mixture with glyoxal

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Holzminden, Germany

Alfred Krempel