Agfa-gevaert Ag

Agfa-gevaert Aktiengesellshcaft

Bruno Mucke

Franz Moll

Wolfgang Schmidt

Klaus Wagner

Cuong Ly

Sieghart Klotzer

Manfred Becker

Walter Patzold

Helmut Reuss

Peter Bergthaller

Michael Missfeldt

Hans Ohlschlager

Manfred Peters

Wilhelm Saleck

Helmut Kampfer

Harald Von Rintelen

Otto Lapp

Erik Moisar

Peter Koepff

Thomas Kaluschke

Dieter Rockser

Gunther Mahlberg

Helmut Mader

Herbert Gareis

Wolfgang Graesser

Angela Slabik

A colour photographic silver halide material having a support and at least one silver halide emulsion layer, which contains a sensitiser of the formula (I), a stabiliser of the formula (II) and a stabiliser of the formula (III) ##STR1## in which R.sub.1 to R.sub.14, X.sub.1, X.sub.2, X.sup..crclbar., L.sub.1 to L.sub.5 and n have the meaning stated in the description, is distinguished by improved storage stability.

Color photographic silver halide material

A color photographic silver halide with a support and at least one silver halide emulsion layer, the silver halide of which is stabilized by compounds I and II, is distinguished by reduced storage fog combined with stronger gradation: ##STR1##

A black & white paper with variable gradation containing a silver chloride-bromide emulsion, which is divided into at least three portions, one of which is sensitised with a blue sensitiser and two further portions are sensitised both with differing quantities of blue sensitiser and with differing quantities of a green sensitiser, wherein the blue sensitiser is of the formula (I) and the green sensitiser is of the formula (II) ##STR1## in which R.sub.1 to R.sub.8, X.sup.(-) and m have the meaning stated in the specification, is distinguished by an extended gradation range.

Black and white paper with variable gradation

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 quick-developing highly sensitive silver halide emulsion distinguished by steep gradation, a minimal increase in fog during storage, improved threshold gradation and low sensitivity to below-threshold pre-exposure is obtained by the addition of a diindoyl disulfide during preparation of the emulsion.

Photographic silver halide emulsion

Color photographic recording material having a layer support and at least one silver halide emulsion layer sensitive to blue light, in which the silver halide of the blue sensitive silver halide emulsion layer is sensitized with a blue sensitizer of the J-band type and contains at least 95 mol % of silver chloride is distinguished by high sensitivity with low fog.

Color photographic recording material and a process for the preparation

Color photographic recording material containing, on a reflective layer support, at least one blue sensitive, at least one green sensitive and at least one red sensitive layer of binder containing silver halide and optionally other light insensitive layers of binder, which binder has been hardened with an instant hardener, said recording material containing either from 100 to 900 mMol of soluble chloride and from 0 to 50 mMol of soluble bromide per mole of Ag or from 0 to 600 mMol of soluble chloride and from 5 to 50 mMol of soluble bromide per mol of Ag is distinguished by an exceptionally slight storage fog.

Color photographic material

The production of a photosensitive silver halide emulsion by precipitation of the silver halide in the presence of gelatine, flocculation and washing of the silver halide precipitated in the presence of the gelatine and redispersion with addition of more gelatine, precipitation being carried out in the presence of a gelatine having a gold number of at most 10 .mu.mol/g gelatine and a cysteine content of at most 6 ppm and redispersion being carried out with a gelatine having a gold number of at least 23 .mu.mol/g gelatine, leads to an emulsion of uniform grain distribution in which undesirably high fogging is avoided.

Production of a silver halide emulsion

The sensitivity/fog ratio can be improved by using photographic silver halide emulsions containing gelatine which has a cysteine content of less than 10 ppm and a gold number of .gtoreq.23 .mu.mol/g.

Photographic silver halide emulsion containing gelatine

Color photographic silver halide material in which at least one layer contains a silver halide emulsion with 95 to 100 mol % of chloride which has been optimally ripened with a combination of at least one sulphur ripening body and at least one compound of the formula ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 denote, independently of one another, hydrogen or alkyl, and X.sup..crclbar. denotes an anion, combines excellent sensitivity with low fog and steep gradation, particularly in the threshold and shoulder region.

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 photographic material with at least one light-sensitive silver halide emulsion is disclosed. The emulsion has been prepared by carrying out the precipitation of the silver halide in the presence of certain imidazoles.

Light-sensitive photographic material

New thioethers of the formula ##STR1## in which Ac represents an acyl radical have been found. They are useful for producing silver halide emulsions for photographic materials.

Growing community of inventors

Bergisch Gladbach, Germany

Bruno Mucke