Patents by Inventor Ralf Wirowski

Ralf Wirowski 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: 6569611
    Abstract: A color photographic silver halide material having a support, which material comprises at last one blue-sensitive, yellow-coupling silver halide emulsion layer and at least one green-sensitive, magenta-coupling silver halide emulsion layer and at least one red-sensitive, cyan-coupling silver halide emulsion layer, and which contains at least one masking coupler which has two chromophores which absorb in the wavelength range from 420 to 750 nm and are eliminable or decolorizable by coupling with the developer oxidation product, is distinguished by improved sensitivity associated with undiminished color purity.
    Type: Grant
    Filed: January 10, 2002
    Date of Patent: May 27, 2003
    Assignee: AGFA-Gevaert
    Inventors: Jan Haller, Ralf Wirowski
  • Patent number: 6531269
    Abstract: A color photographic silver halide material, which has a support which comprises at least one blue-sensitive, yellow-coupling silver halide emulsion layer nearest the light source and at least one green-sensitive, magenta-coupling silver halide emulsion layer and at least one red-sensitive, cyan-coupling silver halide emulsion layer which are further from the light source than is the at least one blue-sensitive layer, and which contains at least one cyan masking coupler which has its maximum absorption above 650 mn, the red-sensitive layers have their maximum sensitivity at 620±20 nm and the absorption of the masking coupler at the maximum sensitivity of the red-sensitive layers is at most 70% of its absorption at 690 mn, is distinguished by improved color reproduction and color saturation in the magenta layer without loss of sensitivity.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: March 11, 2003
    Assignee: Agfa-Gevaert N.V.
    Inventors: Ralf Wirowski, Jan Haller, Stefan Herrmann, Jürgen Jung
  • Publication number: 20020172900
    Abstract: A color photographic silver halide material having a support, which material comprises at last one blue-sensitive, yellow-coupling silver halide emulsion layer and at least one geen-sensitive, magenta-coupling silver halide emulsion layer and at least one red-sensitive, cyan-coupling silver halide emulsion layer, and which contains at least one masking coupler which has two chromophores which absorb in the wavelength range from 420 to 750 nm and are eliminable or decolorisable by coupling with the developer oxidation product, is distinguished by improved sensitivity associated with undiminished color purity.
    Type: Application
    Filed: January 10, 2002
    Publication date: November 21, 2002
    Inventors: Jan Haller, Ralf Wirowski
  • Patent number: 6379879
    Abstract: A color photographic recording material having at least one spectrally sensitized silver halide emulsion layer, characterized in that said silver halide emulsion layer contains an oil former having a pKa value of less than 18 and a DIR coupler and the material contains at least one color coupler, wherein the color coupler and/or the DIR coupler have specific structures, is distinguished by an increased interimage effect in comparison with the prior art without sensitivity being reduced.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: April 30, 2002
    Assignee: Agfa-Gevaert
    Inventors: Jörg Hagemann, Günter Helling, Heinz Wiesen, Ralf Wirowski, Ralf Büscher
  • Publication number: 20020018971
    Abstract: A colour photographic recording material having at least one spectrally sensitised silver halide emulsion layer, characterised in that said silver halide emulsion layer contains an oil former having a pKa value of less than 18 and a DIR coupler and the material contains at least one colour coupler, wherein the colour coupler and/or the DIR coupler have specific structures, is distinguished by an increased interimage effect in comparison with the prior art without sensitivity being reduced.
    Type: Application
    Filed: February 26, 2001
    Publication date: February 14, 2002
    Inventors: Jorg Hagemann, Gunter Helling, Heinz Wiesen, Ralf Wirowski, Ralf Buscher
  • Publication number: 20010036603
    Abstract: A colour photographic silver halide material, which has a support which comprises at least one blue-sensitive, yellow-coupling silver halide emulsion layer nearest the light source and at least one green-sensitive, magenta-coupling silver halide emulsion layer and at least one red-sensitive, cyan-coupling silver halide emulsion layer which are further from the light source than is the at least one blue-sensitive layer, and which contains at least one cyan masking coupler which has its maximum absorption above 650 mn, the red-sensitive layers have their maximum sensitivity at 620±20 nm and the absorption of the masking coupler at the maximum sensitivity of the red-sensitive layers is at most 70% of its absorption at 690 mn, is distinguished by improved colour reproduction and colour saturation in the magenta layer without loss of sensitivity.
    Type: Application
    Filed: March 12, 2001
    Publication date: November 1, 2001
    Inventors: Ralf Wirowski, Jan Haller, Stefan Herrmann, Jurgen Jung
  • Patent number: 6261758
    Abstract: The production of tabular silver bromide-iodide emulsions and silver bromide-chloride-iodide emulsions with an aspect ratio 32, an iodide content from 1 to 40 mol % and a chloride content from 0 to 20 mol %, by the process steps of (a) silver halide nucleus precipitation, and (b) at least one further precipitation of silver halide, wherein rein at least one aromatic five- or six-membered, heterocyclic compound, which is free from—SH—,—SSO2H— and—SSO2R groups, is added in an amount from 10−9 to 10−4 mol/mol silver during nucleus precipitation or during the precipitation of an inner zone of the silver halide grain which is different from the nucleus precipitate, results in an improved speed/grain size ratio and in an increased stability of a photographic material which contains an emulsion produced in this manner.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: July 17, 2001
    Assignee: Agfa-Gevaert
    Inventors: Ralf Wirowski, Hans-Ulrich Borst, Detlev Kapitza, Jörg Siegel, Peter Bergthaller, Heinrich Odenwälder
  • Patent number: 6218097
    Abstract: A colour photographic silver halide material having a support and at least one photosensitive silver halide emulsion layer which contains a magenta coupler of the formula (I) in which R1 to R3, a, b, c and X have the meaning stated in the description, which material contains a DIR coupler of the formula (II) in which R6 to R11 have the meaning stated in the description, is distinguished by improved processing stability.
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: April 17, 2001
    Assignee: Agfa-Gevaert
    Inventors: Peter Bell, Ralf Büscher, Lothar Rosenhahn, Heinz Wiesen, Ralf Wirowski