Patents by Inventor Diethart Reichel

Diethart Reichel 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: 6090928
    Abstract: The present invention relates to a process for the preparation and work-up of N-hydroxyalkylchitosans soluble in aqueous media, comprising the measuresdispersion of chitosan in an aqueous medium,subsequent hydroxyalkylation of the dispersed chitosan andsubsequent work-up of the N-hydroxyalkylchitosan, which comprises carrying out the hydroxyalkylation up to an average degree of substitution (DS) of 2.0, preferably 1.5 to 2.0, if desired removing some of the aqueous medium after the hydroxyalkylation and before the work-up and performing the work-up of the N-hydroxyalkylchitosan by drying.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: July 18, 2000
    Assignee: Clariant GmbH
    Inventors: Reinhard Donges, Diethart Reichel, Birgit Kessler
  • Patent number: 5928709
    Abstract: Low molecular weight cellulose ethers which are suitable as a coating material for solid metered units and as an additive in ceramic compositions or cosmetics formulations or as a polymerization auxiliary are obtained by irradiation of a mixture of a higher molecular weight cellulose ether and a base with electrons.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: July 27, 1999
    Assignee: Clariant GmbH
    Inventors: Reinhard Doenges, Diethart Reichel
  • Patent number: 5719274
    Abstract: Low molecular weight cellulose ethers which are suitable as a coating material for solid metered units and as an additive in ceramic compositions or cosmetics formulations or as a polymerization auxiliary are obtained by irradiation of a mixture of a higher molecular weight cellulose ether and a base with electrons.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: February 17, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Reinhard Doenges, Diethart Reichel
  • Patent number: 5493013
    Abstract: Process for preparing cellulose ethers with cyclic ethers as suspending agents. The present invention relates to a process for preparing cellulose ethers from cellulose and alkylating agents, in the presence of water and bases and at least one water-miscible cyclic ether as the suspending agent, comprising the stages:a) alkalisation,b) subsequent alkylation,wherein the water-miscible cyclic ether is employed already in stage a) or, where appropriate, not until stage b).
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: February 20, 1996
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Diethart Reichel