Patents by Inventor Ekkehard Kramp

Ekkehard Kramp 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).

  • Layers for photographic materials
    Patent number: 4898810
    Abstract: This invention relates to layers for photographic materials, which comprises a polysaccharide which is formed extracellularly by bacterial fermentation of glucose, maltose, sucrose or xylose, if appropriate in the presence of yeast, yeast hydrolysate or casein-hydrolysate, and with mono-, di- and/or tri-valent metal ions, forms gels having a solidification temperature between 24.degree. and 25.degree. C. Gellan gum has proved to be a particularly advantageous polysaccharide for use in the layers according to the invention.
    Type: Grant
    Filed: May 1, 1988
    Date of Patent: February 6, 1990
    Assignee: Ciba-Geigy AG
    Inventors: Ute Eggert, Andreas Engel, Ekkehard Kramp
  • Process for the prevention of darkening and the formation of a sediment in photographic developer solutions
    Patent number: 4254215
    Abstract: A process is described for the prevention of darkening and the formation of a sediment in photographic developer solutions which contain a silver halide developer, a water-soluble silver halide solvent and organic sulfur compounds. The organic sulfur compounds are a combination of (a) an organic thiol compound or thione compound capable of tautomerism and (b) a Bunte salt which contains groups conferring solubility in water. Developer solutions which contain the indicated combination of sulfur compounds are outstandingly stable.
    Type: Grant
    Filed: March 26, 1979
    Date of Patent: March 3, 1981
    Assignee: Ciba-Geigy AG
    Inventors: Ekkehard Kramp, John Lenoir, Max Marthaler
  • Dye bleach preparation for the photographic silver dye bleach process
    Patent number: 3961957
    Abstract: The invention relates to a dye bleach preparation which contains in addition to an acid, a water-soluble iodide and optionally a dye bleach catalyst at least one bifunctional sulphur compound having a sufficient solubility in the preparation and a low vapor pressure and containing at least one HS-group and at least one oxygen, nitrogen, phosphorus or additional sulphur atom, the sulphur atom of each HS-group being separated from the next oxygen, sulphur, nitrogen and phosphorus atom present in the molecule by at least three carbon atoms.The subject of the present invention is a dye bleach preparation for the photographic silver dye bleach process, which contains an acid, a water-soluble iodide and optionally a dye bleach catalyst. The preparation is characterised in that it contains at least one organic, at least bifunctional sulphur compound of which the solubility is at least 5.times.10.sup.-.sup.4 mol per liter of preparation and of which the vapour pressure in the temperature range of -20.degree.
    Type: Grant
    Filed: May 10, 1974
    Date of Patent: June 8, 1976
    Assignee: Ciba-Geigy AG
    Inventors: Ekkehard Kramp, John Lenoir, Max Marthaler, Robert Schaller