Agfa-gevaert Ag

Agfa-gevaert Aktiengesellshcaft

Bayer Aktiengesellschaft

Hans Hlschlager

Heinrich Odenwalder

Reinhart Matejec

Gunter Helling

Erich Wolff

Wolfgang Himmelmann

Gunther Schenk

Manfred Becker

Werner Berthold

Hans-Ulrich Borst

Hubertus Psaar

Karl-Wilhelm Schranz

Hans Langen

Immo Boie

Anita Von Konig

Hans Vetter

Manfred Beck

Friedrich-Wilhelm Kunitz

Johannes Sobel

Lothar Rosenhahn

Manfred Peters

Wilhelm Saleck

Paul Marx

Fritz Nittel

Helmut Kampfer

Thomas Stetzer

Kaspar Wingender

Lothar Endres

Edith Weyde

Dirk Hubner

Thomas Kaluschke

Friedhelm Sommer

Hans-Joachim Schumann

Armin Voigt

Gunther Mahlberg

Helmut Mader

Bernhard Morcher

Karl-Wilhem Schranz

Jurgen Heinecke

Emulsions having an improved sensitivity/grain ratio are obtained when a silver halide emulsion containing up to 20 mol % of AgI is prepared by the precipitation of a silver halide emulsion A containing up to 100 mol % of AgI and the addition of a silver halide emulsion B which contains up to 40 mol % of AgI, has an average grain size of at most 0.25 .mu.m and is always more soluble in aqueous gelatine solution than emulsion A either due to its grain size or due to its iodide content, this being carried out in the presence of at least two compounds selected from imidazole, histidine (.alpha.-amino-.beta.-imidazolyl-(5)-propionic acid) and other monocyclic, 5- or 6-membered heterocyclic compounds which have at least one ring nitrogen atom, are free from SH groups and form sparingly soluble silver salts in weak acid to neutral aqueous solutions, which salts redissolve at pH&gt;9 when ammonia is added, one of the at least two compounds being imidazole or histidine and at least one other compound being a compound other than imidazole or histidine.

Process for the preparation of silver halide emulsions

A photographic recording material on a transparent support having at least one light-sensitive silver halide emulsion layer and optionally conventional interlayers and protective layers, characterized in that the photographic recording material contains, in at least one of the above-mentioned layers, a compound corresponding to formula I, II or III ##STR1## wherein R.sub.1 denotes an unsubstituted or substituted alkyl group, an unsubstituted or substituted aryl group or an unsubstituted or substituted heterocyclic group,

Photographic recording material

A color photographic recording material containing, on a layer support, at least one blue sensitive silver halide emulsion layer and a yellow coupler associated therewith, at least one green sensitive silver halide emulsion layer and a magenta coupler associated therewith and at least one red sensitive silver halide emulsion layer and a cyan coupler associated therewith also contains, in a layer which is not sensitive to light, a compound corresponding to formula I (stabilizer) ##STR1## wherein R.sup.1 denotes H or a group which can be split off under alkaline development conditions;

Color photographic recording material for the production of color images

Light sensitive color photographic silver halide material containing at least one light sensitive silver halide layer with which a conventional diffusion fast color coupler is associated and optionally other layers, both light sensitive and light insensitive, in which material the one or more than one light sensitive silver halide layer contains, at a concentration of 10.sup.-3 to 10 mmol/mol of silver halide, a compound corresponding to the following formula

Color photographic material

A photosensitive silver halide material comprising a support and at least one photosensitive silver halide emulsion layer, of which the emulsion contains an effective quantity of at least one compound from each of at least two classes A, B, C and D defined hereinafter:

Silver halide recording material

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.

A silver image produced by imagewise exposure, development and fixing of a photographic material containing at least one silver halide emulsion layer is stabilized by being subjected after fixing to treatment by a stabilizing bath containing a compound corresponding to general formula I

Process for stabilizing photographic silver images

A color photographic silver halide material of the negative type, in which at least one silver halide emulsion layer contains as compound corresponding to the following formula

Improved photographic recording materials contain silver halide grains having at least two zones differing in their halide composition and, as stabilizer, a compound corresponding to the formula ##STR1##

Photographic recording material and process for the production of

Water soluble sulphates of a heteroaromatic bis- or poly-sulphone are suitable for use as hardeners for proteinaceous binders, in particular in photographic layers.

Hardeners for proteins, a layer of binder hardened therewith and a

Process for the production of color images by the color photographic dye diffusion process in which development is brought about by heat and water. The combination of antifoggants added to the light-sensitive material, in particular the combination of compounds of formulae I and II, produces a marked improvement in storage stability and constancy of sensitivity with good D.sub.min /D.sub.max ratios. ##STR1## R.sup.1 denotes hydrogen, alkyl with up to 6 carbon atoms, hydroxy, halogen, alkoxy or substituents which together form a condensed benzene ring, and in formula II below: ##STR2## R.sup.2 denotes a group which can be split off in the process of development of the material and

Color photographic heat development process

Remarkably high interimage and Eberhard effects are obtained when yellow DIR couplers corresponding to formuls I are added to multilayered color photographic recording materials, in particular to the green-sensitive or red-sensitive layers. These couplers can improve the sharpness and color reproduction. ##STR1## R.sup.1 denoted alkyl or aryl, R.sup.2 denotes alkyl with up to 18 carbon atoms,

Color photographic recording material containing a yellow DIR coupler

Photographically produced black-and-white images (silver images) are stabilized against subsequent destruction of the silver image, in particular against the occurrence of so-called microspot defects, by treatment of the finished silver image with an aqueous after-treatment bath containing an amino-1,2,4-triazole.

Stabilization of a photographically produced silver image using an

A color photographic recording material developable by heat treatment and comprising at least one binder layer, which contains photosensitive silver halide, optionally a substantially non-photosensitive silver salt and a color providing compound (dye releaser), can be improved in regard to the Dmin/max relation and in regard to sensitivity by addition of a compound corresponding to formula I

Color photographic recording material developable by heat treatment

For electronic image recording in one or more colors a photographic recording material comprising in at least one layer photo-sensitive silver halide and a compound capable of luminescence is image-wise exposed and developed to produce a latent luminescence image. The image information contained in the latent luminescence image is scanned photoselectively by a luminescence spectroscopic process and is recoded electronically in the form of monochromatic luminescence signals. The process provides images in one or more colors and is highly sensitive. Recording materials of extremely low silver application can be used.

Growing community of inventors

Bergisch Gladbach, Germany

Hans Hlschlager