Sensitivity increase from alkynylamineazole, sensitizing dye, and chalcogenazolium salt added before heat cycle
US5411854A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1993 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Dec 29, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/42
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention is accomplished by providing a combined process of chemical and spectral sensitization comprising providing a silver halide emulsion, adding a sulfur or gold chemical sensitizer, adding a finish modifier ##STR1## wherein X is --O--, --S--, --Se--, ##STR2## Y.sup.1 and Y.sup.2 individually represent hydrogen or an aromatic nucleus or together represent the atoms completing a fused aromatic nucleus; R is hydrogen or lower alkyl of from 1 to 5 carbon atoms; and R.sub.1 is a hydrogen or methyl, provided that Y.sup.1 and Y.sup.2 individually represent hydrogen or an aromatic nucleus when R.sub.1 is hydrogen, adding dye, and PA0 adding a hydrolyzable quaternized chalcogenazolium salt of a middle chalcogen, PA0 heating to a temperature sufficient to cause sensitization of said silver halide to take place, and cooling to recover the sensitized emulsion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.