Agfa-gevaert Ag

Agfa Gevaert Nv

Agfa-gevaert Aktiengesellscaft

Sieghart Klotzer

Erik Moisar

Willy Joseph Vanassche

Herman Alberik Pattyn

Manfred Becker

Bruno Mucke

Otto Lapp

Erich Wolff

Gunter Renner

Heinz Meckl

Manfred Peters

Helmut Haseler

Harald Von Rintelen

Kaspar Wingender

Wolfgang Sauerteig

Thomas Kaluschke

Gunther Mahlberg

Jens-Peter Grimm

A silver halide material for colour photography, comprising 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 applied to the support and conventional intermediate and protective layers, the emulsion in at least one of the silver halide layers comprising not less than 80 mol-% AgCl and not more than 0.5 mol-% AgI, and the last-mentioned silver halide emulsion is doped with at least one compound of a metal in the groups (a) and (b), where (a) comprises rhodium, iridium, osmium, ruthenium, rhenium and cadmium and (b) comprises gold and platinum. The material has very good development kinetics.

Recording material for color photography

A color photographic silver halide material comprising at least one negatively developing, green-sensitive silver halide emulsion layer containing at least one magenta coupler can be adjusted to any desired sensitivity of that layer without any changes in other sensitometric properties by addition of at least one compound corresponding to general formula (I) ##STR1## wherein is hydrogen or halogen,

Color photographic silver halide material

A new process for maintaining the properties of the developer in the preparation of colored images by development of exposed silver halide-containing material at an alkaline pH in a developer bath containing p-phenylenediamine derivative and at least 40 mol-% of the silver halide consisting of silver chloride and replenishing the color developer in the bath in such a limited quantity that no overflow occurs but it is sufficient to make up for the loss of bath constituents. This process preserves the sensitive results from development during use of the developer bath.

Process for the production of color photographic images comprising

A heat developable color photographic recording material is improved in its D.sub.min /D.sub.max ratio and sensitivity if it contains a silver halide emulsion in which the grains have at least three zones differing in their silver halide composition.

Color photographic recording material developable by heat

A recording material having improved sharpness and color reproduction contains as uppermost layer a green-sensitive silver chloride emulsion having a layered grain structure, the ratio of diameter to thickness of the silver halide grains being at most 5.

Color photographic recording material

Improved silver halide emulsions are obtained by the combined use of an iridium compound and an imidazole before termination of crystal growth.

Color photographic recording material containing a silver halide

A silver halide emulsion rich in chloride is described which has grains having a layered grain structure with a core and at least one layer encasing the core.

Emulsion rich in silver chloride, photographic recording material and

A chloride-rich silver halide emulsion with grains having in the interior thereof a zone having a high bromide content is described.

Emulsion having high silver chloride content, photographic recording

Surface-sensitized silver halide grains having a core/shell structure show improved properties.

Photographic silver halide emulsion

Direct positive silver halide emulsions are provided which contain fogged silver halide grains the said grains being heterodisperse and containing silver iodide in an amount of more than 10 mole % and at most 20 mole % relative to the total amount of silver halide. The emulsions have increased sensitivity and reduced gradation which is suitable for continuous tone reproduction.

Direct-positive emulsion containing fogged, silver halide grains of

An improvement in the stability of a direct positive emulsion layer in photographic material is obtained by the inclusion of a compound which provides in the image-wise exposed and developed direct positive emulsion layer a greater difference between the density of the image in the unexposed parts of the layer and the density in the exposed parts. The compound provides in the emulsion a characteristic curve related to a density value at maximum density which is at least twice the analogous density value at minimum density.

Direct-positive photographic material

Direct positive silver halide emulsions are provided which contain fogged silver halide grains with a layered grain structure wherein the external shell of the silver halide grains comprise up to 20 mole % of silver iodide based on the silver halide of the shell. The emulsions show improved sensitivity and produce images of improved maximum density.

Direct positive silver halide elements

Direct positive silver halide emulsions are provided which contain fogged homodisperse silver halide grains having a silver iodide content of more than 10 mole % and at most 20 mole % relative to the total amount of silver halide. These emulsions have higher sensitivity than corresponding fogged emulsions with less silver iodide content.

Direct positive emulsions containing fogged, monodispersed silver halide

A photographic material for producing direct-positive photographic images with at least one silver halide emulsion layer containing unfogged heterodisperse silver halide grains with a core which consists predominantly of silver bromide and a localised phase with a high silver chloride content of at least 20 mols-%, the total concentration of silver chloride, based on the total silver halide content of the grain, is less than 30 mols-%, and at least 10% by weight of the silver halide grains have a diameter which deviates by at least 40% from the average grain diameter in which the silver halide grains are not or only slightly chemically sensitised on the surface.

Photographic emulsion containing unfogged, heterodisperse layered silver

A direct-positive photographic material for producing images by fogging development wherein the photographic material contains an unfogged silver halide emulsion layer. The silver halide grains in the unfogged emulsion have a layered grain structure wherein there is a first phase in which is localized a relatively high silver chloride content of at least 20 mol percent based on the total silver halide content of the grain. A second phase contains from less silver chloride than the first phase down to no silver chloride and the total silver chloride in the grain does not exceed 30 mol percent. The physical position of the first phase in the grain is not critical. The emulsion is either not chemically sensitized or only slightly sensitized. The photographic material and its use includes both producing black and white and colored photographic images and has high sensitivity to light and by fogging development yields pure image whites.

Growing community of inventors

Cologne, Germany

Sieghart Klotzer