Patents by Inventor Lothar Rosenhahn

Lothar Rosenhahn 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: 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
  • Patent number: 6207283
    Abstract: A polymer of the formula (I): in which X1 means H or (R1)1+1—L1CO—, X2 means —(L2)m—OH or R1 means —COO−M+, —SO3−M+ or (M+)2PO32−, L1 means alkylene, arylene, aralkylene or cycloalkylene, L2 means the residue of a polyether having an average molecular weight of 200 to 3000 (number average), M+ means a cation, l means a number from 0 to 4, m means a number 0 or 1 and n means a number from 0 to 20, wherein m+n is ≧1.
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: March 27, 2001
    Assignee: Agfa-Gevaert
    Inventors: Peter Bell, Günter Helling, Beate Weber, Ralf Büscher, Lothar Endres, Lothar Rosenhahn, Rainer Scheerer, Lydia Simon, Thomas Stetzer
  • Patent number: 6093524
    Abstract: A color photographic film having a support, 2 or 3 red-sensitive, cyan-coupling silver halide emulsion layers, 2 or 3 green-sensitive, magenta-coupling silver halide emulsion layers, 2 or 3 blue-sensitive, yellow-coupling silver halide emulsion layers, conventional interlayers and protective layers together with a yellow filter layer arranged closer to the support than the blue-sensitive layers, wherein at least one green-sensitive silver halide emulsion layer is arranged further away from the support than all the other photosensitive layers, exhibits improved sharpness without color distortion if at least 50% of the projected surface area of the silver halide emulsion of the green-sensitive silver halide emulsion layer, of which there is at least one, consists of tabular silver halide grains having an aspect ratio of at least 3.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: July 25, 2000
    Assignee: Agfa-Gevaert NV
    Inventors: Rainer Scheerer, Lothar Endres, Hans-Ulrich Borst, Lydia Simon, Thomas Stetzer, Peter Bell, Lothar Rosenhahn, Ralf Buscher
  • Patent number: 6087083
    Abstract: A colour photographic material in which a package of layers is provided which consists, in the stated sequence, of (a) a silver halide-free layer containing colour coupler, (b) a layer containing silver halide and (c) a silver halide-free layer containing colour coupler, wherein at least one of layers (a) and (c) consists to an extent of at least 20 vol. % of a synthetic polymer, is distinguished by an improved grain/sensitivity ratio.
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: July 11, 2000
    Assignee: Asfa-Gevaert N.V.
    Inventors: Peter Bell, Ralf Buscher, Lothar Endres, Lothar Rosenhahn, Rainer Scheerer, Lydia Simon, Thomas Stetzer
  • Patent number: 6060227
    Abstract: A color negative film having a support, at least one blue-sensitive, yellow-coupling silver halide emulsion layer, at least one green-sensitive, magenta-coupling silver halide emulsion layer and at least one red-sensitive, cyan-coupling silver halide emulsion layer, wherein at least one of the color-sensitive silver halide emulsion layers consists of at least two sub-layers of differing photographic sensitivity, the coupler application rate in the most highly sensitive layer of the color sensitive silver halide emulsion layer, of which there is at least one, consisting of at least two sub-layers of differing photographic sensitivity, is no more than 0.05 mmol/m.sup.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: May 9, 2000
    Assignee: Agfa-Gevaert NV
    Inventors: Ralf Buscher, Peter Bell, Hans-Ulrich Borst, Lothar Rosenhahn, Jorg Siegel, Thomas Stetzer
  • Patent number: 6017689
    Abstract: A color photographic silver halide material having at least two blue-sensitive, yellow coupler containing silver halide emulsion layers, at least two green-sensitive, magenta coupler containing silver halide emulsion layers and at least two red-sensitive, cyan coupler containing silver halide emulsion layers together with conventional interlayers and protective layers, wherein photosensitive layers of identical color sensitivity differ with regard to the photographic sensitivity thereof and the more highly sensitive layers are arranged further away from the support than the less sensitive layers of identical color sensitivity, which material contains, in a layer which is arranged further from the support than the most highly sensitive, blue-sensitive layer, both at least one yellow coupler and at least one magenta or cyan coupler, is distinguished by improved grain and sensitivity combined with very good color reproduction.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: January 25, 2000
    Assignee: Agfa-Gevaert AG
    Inventors: Peter Bell, Ralf Buscher, Lothar Endres, Lothar Rosenhahn, Rainer Scheerer, Lydia Simon, Thomas Stetzer
  • Patent number: 5306605
    Abstract: A photographic recording material comprising a carrier and at least one photosensitive silver halide emulsion layer, a non-photosensitive layer and optional conventional intermediate and protective layers, characterised in that the photographic recording material (1) contains at least one silver halide emulsion layer having a silver iodide content .gtoreq.3 mol % and an average grain diameter .ltoreq.0.4 .mu.m, and (2), at least in one layer, contains a compound having the formula I ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 denote hydrogen, an optionally substituted hydrocarbon radical, an optionally substituted alkylthio, alkyloxy or arylthio radical, an optionally substituted amino group, OH or halogen or R.sup.1 and R.sup.2 together denote the radical for completing a carbocyclic or heterocyclic ring,R.sub.4, R.sub.5 denote hydrogen, an optionally substituted alkyl or aryl radical, or an optionally substituted heterocyclic radical,R.sub.6, R.sub.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: April 26, 1994
    Assignee: AGFA-Gevaert AG
    Inventors: Heinrich Odenwalder, Lothar Rosenhahn, Thomas Stetzer
  • Patent number: 5006457
    Abstract: The invention relates to a photographic recording material comprising a layer support and, arranged thereon, at least one photosensitive silver halide emulsion layer which contains an antifogging agent corresponding to formula (I) ##STR1## in which A, R.sub.1 and R.sub.2 are as defined in the specification. The antifogging agents according to the invention reduce fogging without significantly affecting gradation and improve the staility of the photographic material in storage.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: April 9, 1991
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans Vetter, Hans hlschlager, Heinrich Odenwalder, Bernhard Morcher, Friedhelm Sommer, Lothar Rosenhahn
  • Patent number: 4603102
    Abstract: The photographic silver halide recording material contains particles of a hydroxyalkyl-alkyl cellulose dicarboxylic acid semiester having a particle size of from 0.5 to 8 .mu.m and a particle size distribution of up to .+-.2 .mu.m dispersed in a hydrophilic colloid in at least one of its outermost layers.
    Type: Grant
    Filed: June 26, 1985
    Date of Patent: July 29, 1986
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Wolfgang Himmelmann, Fritz Nittel, Rudolf Meyer, Lothar Rosenhahn
  • Patent number: 4559296
    Abstract: New dyes corresponding to the following general formula: ##STR1## wherein the substituents are as defined in the specification, are suitable for use in photographic recording materials.
    Type: Grant
    Filed: April 25, 1984
    Date of Patent: December 17, 1985
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Peter Bergthaller, Lothar Rosenhahn, Karl J. Herd, Hauke Fuerstenwerth, Rudolf Stolzenburg
  • Patent number: 4414309
    Abstract: Compounds corresponding to the following general formula ##STR1## wherein R.sup.1 represents hydrogen, an aliphatic or cycloaliphatic group, an aralkyl group, an aryl group, a heterocyclic group or one of the following groups: --CO--alkyl, --CO--aryl, --CO--heterocyclic group, --SO.sub.2 --alkyl, --SO.sub.2 --aryl, --CO--O--alkyl, --CO--NH--NH.sub.2, ##STR2## and R.sup.2 represents hydrogen, an aliphatic or cycloaliphatic group, an aralkyl group, an aryl group, alkoxy, aroxy, carboxyl, carbamoyl, alkoxycarbonyl, an alkyl or aryl group attached through a carbonyl group, cyanogen, an amino group optionally substituted by alkyl, aralkyl, aryl or acyl, or a cyclic amino groupmay be used as additives in the layers of color photographic recording materials to improve the stability of color couplers, in particular magenta couplers, against formaldehyde.
    Type: Grant
    Filed: November 24, 1982
    Date of Patent: November 8, 1983
    Assignee: Agfa-Gavaert Aktiengesellschaft
    Inventors: Hans Langen, Lothar Rosenhahn, Erich Wolff
  • Patent number: 4358531
    Abstract: Compounds of the formula ##STR1## wherein the substituents have the meaning indicated in the specification are suitable as latent image stabilizer in silver halide materials.
    Type: Grant
    Filed: October 9, 1981
    Date of Patent: November 9, 1982
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Anita von Konig, Franz Moll, Lothar Rosenhahn
  • Patent number: 4276373
    Abstract: A photosensitive recording material containing at least one silver halide layer and an azo dye is disclosed.
    Type: Grant
    Filed: March 19, 1980
    Date of Patent: June 30, 1981
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Hans Ohlschlager, Lothar Rosenhahn, Wolfgang Sauerteig
  • Patent number: 4210714
    Abstract: Process for the preparation of silver images by imagewise exposure of a photographic material comprising at least one light-sensitive silver halide emulsion layer and treatment of the material with a developer composition, wherein the improvement comprises the development is carried out in the presence of 3-mercapto-5-(2-furyl)-1,2,4-triazole. The 3-mercapto-5-(2-furyl)-1,2,4-triazole decreases the fog during development, and when this is the first development in a black-and-white or color reversal process, increases the reversal silver or color density.
    Type: Grant
    Filed: March 15, 1978
    Date of Patent: July 1, 1980
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Heinrich Odenwalder, Anita von Konig, Franz Moll, Walter Patzold, Lothar Rosenhahn, Friedhelm Sommer
  • Patent number: 4067741
    Abstract: 1-Sulphonyl-4-amino-pyridinium salts are used as quick acting hardeners for protein-containing layers, in particular gelatine layers, for photographic purposes.
    Type: Grant
    Filed: October 19, 1976
    Date of Patent: January 10, 1978
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Peter Bergthaller, Wolfgang Himmelmann, Lothar Rosenhahn
  • Patent number: 4055427
    Abstract: As quick-acting hardeners for layers which contain protein, in particular gelatin layers for photographic purposes carbamoyl oxypyridinium salts are used.
    Type: Grant
    Filed: February 15, 1977
    Date of Patent: October 25, 1977
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Peter Bergthaller, Wolfgang Himmelmann, Wolfgang Sauerteig, Lothar Rosenhahn
  • Patent number: 4052215
    Abstract: A color photographic material comprising at least one light-sensitive silver halide emulsion layer having preferably a non-diffusing color coupler associated to it and at least one non-lightsensitive binder layer containing a colloidal silver dispersion provides less contact fog and a better color reproduction if the non-lightsensitive binder layer containing the colloidal silver dispersion contains also a soluble iodide, particularly sodium, potassium or ammonium iodide. Alternatively the soluble iodide may also be contained in a non-lightsensitive binder layer adjacent that binder layer which contains the silver dispersion.
    Type: Grant
    Filed: November 8, 1976
    Date of Patent: October 4, 1977
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Franz Moll, Lothar Rosenhahn