| PATENT CLAIMS |
Method for prepg a light-sensitive AgX photographic emulsion comprising performing > 3 distinct precipitation steps in an aq medium into a reaction vessel, followed by desalting by means of flocculation & washing or by means of
ultrafiltration, said emulsion comprising gelatin having a methionine content < 800 ppm as a colloidally stabilizing binder & {100} tabular AgX grains contg > 50 mole % of AgCl, wherein > 60% by number of all grains is provided by said tabular grains, & wherein said tabular grains exhibit an av aspect ratio > 2, an av thickness < 0.25 micro.m with a variation coefficient < 0.25, & an av equiv. circular crystal diam > 0.3 micro.m with a variation coefficient < 0.2; said 3 distinct precipitation steps being a nucleation step & 2 growth steps, said method being further characterized by introducing after ending the nucleation step one or more crystal dislocation(s) onto nuclei formed in the said nucleation step in order to provide anisotropic growth of the said nuclei into {100} tabular grains, wherein in the said nucleation step from 5-15% of the total available amount of AgNO3 is provided & wherein Ag ions & halide ions are introduced in order to get cubic nuclei rich in AgCl having an edge of < 0.25 micro.m, wherein introducing said crystal dislocation(s) is performed within a time ripening step after the nucleation step in order to get a number of dislocation lines of < 5, in one & the same crystallographic plane, & wherein said physical ripening step between introducing said dislocation(s) & growing the nuclei having said dislocation(s) in a first growth step proceeds within a time interval from 2 to 10 min
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