Tabular grain emulsions exhibiting relatively constant high sensitivities
US5709988A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 1995 |
| Grant date | Jan 20, 1998 |
| Priority date | — |
| Expiry date | Mar 7, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2001/03558
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Radiation-sensitive emulsions are disclosed comprised of high bromide tabular grains containing a peripheral band of increased iodide concentration. The tabular grains exhibit an average equivalent circular diameter of at least 2.0 .mu.m and are of a face centered cubic crystal lattice structure of the rock salt type. The tabular grains include central and peripheral regions extending between their major faces. The peripheral region is up to 0.2 .mu.m in width and contains an iodide concentration at least 2 mole percent higher than that of the central region measured at a location adjacent the peripheral region. Dislocations are present in the peripheral region to increase sensitivity and are minimized in the central region to maintain relatively constant sensitivities when pressure is applied locally.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.