Patents by Inventor Hans-Gunter Donner

Hans-Gunter Donner 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).

  • Regeneration of spent developers
    Patent number: 4680123
    Abstract: Anion exchangers containing OH groups as exchange active groups are suitable for the regeneration of photographic developers.
    Type: Grant
    Filed: September 30, 1985
    Date of Patent: July 14, 1987
    Assignee: Agfa Gevaert Aktiengesellschaft
    Inventors: Ubbo Wernicke, Heinz Meckl, Hans-Gunter Donner, Jurgen Frosch