Patents by Inventor Karl H. Blocher

Karl H. Blocher 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: 4294985
    Abstract: In the production of thiocarbohydrazide by reacting hydrazine hydrate with carbon disulphide in the presence of water to form in a first stage hydrazinium dithiocarbazinate, subsequently thermally decomposing the hydrazinium dithiocarbazinate in a second stage to form thiocarbohydrazide, and recovering the thiocarbohydrazide from the reaction medium, the improvement which comprises effecting the entire reaction in the mother liquor of a preceding batch, carrying out the first reaction stage at a temperature between about 25.degree. C. and 45.degree. C., with injection of carbon disulphide below the surface of the reaction mixture; carrying out the second stage at about 62.degree. to 65.degree. C. without prior isolation of the intermediate product; filtering off the thiocarbohydrazide formed after cooling, separating the amount of mother liquor in excess of that required for the next batch, and feeding the balance of the mother liquor to the next batch.
    Type: Grant
    Filed: June 15, 1979
    Date of Patent: October 13, 1981
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gunther Cramm, Karl H. Blocher