Patent · US Expired

Process for the chemical sensitization of silver halide photographic emulsions

US5169751A · kind A · utility

3Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 15, 1991
Grant dateDec 8, 1992
Priority date
Expiry dateJan 15, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C2001/091
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The invention relates to a novel process for the chemical sensitization of silver halide photographic emulsions. The process according to the invention comprises adding as additional sensitizing agents a 40-260 .mu. moles/mole of a cyclic polyether containing 1 nitrogen and 5 oxygen atoms, or 2 nitrogen and 4 oxygen atoms, or 3 nitrogen and 3 oxygen atoms, or 4 nitrogen and 2 oxygen atoms as well as 12 carbon atoms and/or their complexes formed with gold and/or palladium and optionally 40-260 .mu. moles/mole of silver halide) of gold (I) or gold (III) sulfide to the sulfur-sensitized emulsion, and employing the cyclic polyether in relation to the noble metal salt in a molar ratio of 0.5:1-5:1 for the complex formation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.