High contrast photographic materials
US5068167A · kind A · utility
3Cited by
6References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 29, 1988 |
| Grant date | Nov 26, 1991 |
| Priority date | — |
| Expiry date | Mar 29, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/08
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Pepper fog may be reduced in high contrast photographic materials comprising silver halide emulsion in association with a hydrazine by the presence of at least 0.001 mole per mole of silver halide of a water-soluble bromide and/or water-soluble chloride. Suitable water-soluble bromides and chlorides are alkali metal bromides and chlorides which are advantageously added to the silver halide emulsion after physical ripening and washing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.