Core/shell direct positive silver halide emulsion with silver halide solvent removal
US5424168A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1994 |
| Grant date | Jun 13, 1995 |
| Priority date | — |
| Expiry date | Aug 8, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/43
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
There are disclosed an internal latent image type direct positive light-sensitive emulsions having improved spectral sensitization performance, and chemical sensitization performance, and color diffusion transfer photographic film units in which said emulsions are used. The emulsions are prepared by subjecting a silver halide grain, which forms an internal nucleus, to chemical sensitization, in the presence of an organic silver halide solvent, and adding a solid adsorbing agent, before finishing the formation of an outer shell silver halide phase, to remove a part or all of the silver halide solvent, wherein the emulsions may further contain a tabular silver halide grain having an average grain diameter of at least 0.3 .mu.m and a ratio of an average grain diameter to an average grain thickness of 2 or more, based on 50% or more of the total silver halide grains.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.