High tabularity high chloride emulsions of exceptional stability
US5275930A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 27, 1992 |
| Grant date | Jan 4, 1994 |
| Priority date | — |
| Expiry date | Aug 27, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/43
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A chemically sensitized high chloride tabular grain emulsion is disclosed. The tabular grains have {100} major faces. Chemically sensitized silver halide epitaxial deposits containing less than 75 percent of the chloride ion concentration of the tabular grains and accounting for less than 20 mole percent of total silver are located at one or more of the corners of the tabular grains. The emulsions are prepared by first forming the host tabular grains, epitaxially depositing silver halide selected to contain less than 50 percent of the chloride ion concentration of the tabular grains, adsorbing a photographically useful compound to the surfaces of the silver halide epitaxial deposits, and chemically digesting the emulsion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.