Abstract: A color photographic recording material with a reflective support which contains a spectrally sensitized silver halide emulsion containing at least one sensitizer for the spectral region B in a layer free from color coupler adjacent at least one dye-producing silver halide emulsion layer sensitized for the spectral region A, the sensitivity of the spectrally sensitized silver halide emulsion of the layer free from color coupler being lower by 0.6 to 2.5 log H units than the sensitivity of the sensitized silver halide emulsion of the dye-producing silver halide emulsion layer, is distinguished by an extended gradation range in the region of the maximum densities and, hence, by distinctly improved fine detail resolution at high densities.

Abstract: 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.

Abstract: A gradation-variable BW paper comprising only one silver halide emulsion layer, in which re-sensitization is avoided, is obtained with a mixture of at least two photosensitive silver halide emulsions, of which one has its absorption maximum in the range from 480 to 580 while the other has its absorption maximum below 480 nm, providing the emulsion which has its absorption maximum below 480 nm contains a compound corresponding to the following formula ##STR1## in which X represents the remaining members of an optionally benzo- or naphtho-condensed heterocycle optionally containing further substituents.

Abstract: A gradation variable black-and-white paper containing only one light sensitive silver halide emulsion layer in which transfer of sensitization is prevented may be obtained by sensitization with at least one compound corresponding to the following formula ##STR1## in which at least one of the groups R.sub.1, R.sub.5 or R.sub.6 is halogen.

Abstract: Propane or butane sultones are prepared by the thermal decomposition of the corresponding aryl sulfoalkyl ethers wherein the alkyl part has three or four carbons between the sulfo group and the ether oxygen. When a tertiary amine is present, the final product is the corresponding sulfoalkyl quaternary salt of the tertiary amine.

Abstract: Photographic recording materials which contain a developer substance or a precursor thereof produce better results if in addition they contain a sulphite, a disulphite or a compound capable of releasing sulphite in the photographic material.

Abstract: Compounds corresponding to the following formula(MS--Het--(Ar).sub.m --NR.sup.1 --CO) .sub.n R.sup.2which are contained in a color-photographic recording material in a silver-free layer between a layer containing colloidal silver and a silver halide emulsion layer, improve the storage stability of the material.

Abstract: 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.

Abstract: Quaternary sulfoalkyl or sulfoalkenyl salts of tertiary amine bases are prepared by reacting the tertiary amine bases at elevated temperatures with a hydroxy alkane sulfonic acid or a hydroxyalkene sulphonic acid.

Abstract: Tertiary amines may be quaternized by heating them with a sulfoalkylating agent of this invention to a temperature of from 100.degree. to 250.degree. C. The sulfoalkylating agents which are believed to be hydroxy alkane sulfonic acid sulfoalkyl esters are free from sultone and are prepared by heating a hydroxy alkane sulfonic acid of propane or butane or the corresponding sultone to a temperature in the region of from 80.degree. to 180.degree. C. in the presence of water in an amount of 1 to 4 moles per mole of hydroxy alkane sulfonic acid or alkane sultone.

Abstract: Sulfoalkylating agents free from sultones may be obtained by heating hydroxy alkane sulfonic acids of propane or butane or the corresponding sultones having 5 or 6 ring members with up to four times the molar quantity of water to a temperature in the region of from 80.degree. to 180.degree. C. The sulfoalkylating agents are believed to be the "dimeric esters" of the hydroxy alkane sulfonic acids.

Abstract: Sulphoalkyl and sulphoalkenyl quaternary salts of heterocyclic nitrogen compounds are prepared by reacting heterocyclic compounds containing a tertiary ring nitrogen atom at an elevated temperature with an O-sulphoalkyl or O-sulphoalkenylisourea compound.

Abstract: A photographic material having a light-sensitive silver salt emulsion layer which layer contains a silver salt developer of the chroman series having the formula defined below.

Abstract: Heat developable light-sensitive photographic material having a layer which contains a light-sensitive combination of a silver compound substantially insensitive to light, a reducing agent for that silver compound and a polymethine sensitizer. The exposed material is heated so that the silver compound in the exposed areas is reduced and a visible silver image is formed.