High bromide emulsions containing a restricted high iodide epitaxial phase on (111) major faces of tabular grains beneath surface silver halide
US5698387A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 1996 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Aug 30, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/03
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photographic emulsion is disclosed comprised of a dispersing medium and radiation-sensitive grains with greater than 50 percent of total grain projected area being accounted for by tabular grains comprised of (1) a tabular host portion containing greater than 50 mole percent bromide, based on silver, and having spaced parallel {111} major faces, (2) a first epitaxial phase containing greater than 90 mole percent iodide, based on silver, accounting for less than 60 percent of total silver and overlying from 15 to 90 percent of the major faces, and (3) surface silver halide of a face centered cubic crystal lattice structure overlying at least a portion of the first epitaxial phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.