Agfa-gevaert Ag

Agfa Gevaert Nv

Agfa-gevaert Aktiengesellshcaft

Franz Moll

Anita Von Konig

Lothar Rosenhahn

Bruno Mucke

Klaus Wagner

Walter Patzold

Heinrich Odenwalder

Ubbo Wernicke

Robert J Pollet

Artur Botta

Christian Rasp

Hans Ohlschlager

Reinhart Matejec

Wilhelm Saleck

Harald Von Rintelen

Otto Lapp

Lothar Endres

Rainer Scheerer

Herman Adelbert Philippaerts

Friedhelm Sommer

Peter Koepff

Walter Gauss

Theofiel H Ghys

Oskar Riester

Hans Josephus Corluy

Herbert Muller

Marie Hase

Johannes Hartl

Herbert Gareis

Wolfgang Graesser

Wolfgang Muller-Bardorff

Ingeborg Holl

A photographic recording material which has at least one silver halide emulsion layer containing gelatine, at least one protective layer and at least one hardening layer and in which the protective layer is further removed from the layer support than any silver halide emulsion layer and the hardening layer is further removed from the layer support than any other layer and contains an effective quantity of at least one instant hardener will have improved stability in storage under moist, warm conditions if the protective layer contains an effective quantity of at least one azaindene.

Photographic recording 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.

Color photographic silver halide material

A yellow silver sol containing a binder is concentrated by flocculation in the presence of a calcium-free gelatin, a water-soluble chloride being added to the flocculation and/or after the redispersion.

Process for concentrating yellow silver sols

Silver halide emulsions are prepared by precipitating a silver halide emulsion I on a more sparingly soluble silver halide emulsion II in the presence of a silver halide solvent wherein the emulsion I has been prepared in the presence of a compound inhibiting grain growth.

Process for the preparation of silver halide emulsions, photographic

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.

Photographic material, process for the production thereof and process

A color photographic material is provided in which the interimage effect is adjusted to provide optimum color reproduction. The photographic material comprises an emulsion referred to as type I emulsion, which releases an inhibitor on development and another emulsion with underripened grains which are more soluble than those of the type I emulsion.

Photographic material with interimage effect

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.

Photographic material with improved properties

Fine-grain silver halide emulsions of the Lippmann-type are described which comprise derivatives of heterocyclic mercaptans corresponding to the formulae: ##STR1## wherein: each of Z.sub.1 and Z.sub.2 represents the atoms necessary to complete a 5- or 6-membered heterocyclic ring system,

Photographic Lippmann emulsions

Photographic panchromatic black-and-white silver halide recording material having two silver halide emulsion layers wherein a layer, called hereinafter first layer, has a panchromatic sensitivity and another layer, called hereinafter second layer, has a blue sensitivity, which is, when determined on comparable wedge images, at density 0.3 at least 0.6 log I.t units higher than its separately considered green and red sensitivity, wherein for the determination of the sensitivities a blue filter, a green filter, and a red filter as characterized in FIG. 1 are used, both said layers having a substantially identical threshold sensitivity to blue light and the spectral sensitivity of this material at 650 nm being at least 0.8 powers of ten lower than at 620 nm, the sensitivity beyond 650 nm diminishing even further.

Photographic materials suited for the production of color separations

The process for the preparation of silver dispersions for antihalation and filter layers in photographic material by reducing silver salts in the presence of a heterocyclic 5-membered or 6-membered compound which has a ##STR1## group in its 1,2,3-position and a 2-aminoalkyl or 2-hydroxyalkyl group or an alkylene chain which is linked through the 1- and 2-position. The process provides neutral grey silver dispersions without using cadmium salts, for the reduction of the silver salts.

Process for the preparation of silver dispersions for filter layers and

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.

Color photographic multilayered material with improved color density

Photographic materials containing in at least one photographic layer as antihalation- or filter-dyes mono-, tri- or pentamethineoxonoles of 1-sulfolanyl pyrazolones, which dyes can be easily decolorized and washed out on treatment of the photographic material in photographic processing.

Growing community of inventors

Leverkusen, Germany

Franz Moll