Patent · US Expired

Process for producing silver halide photographic material

US5130212A · kind A · utility

1Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 19, 1990
Grant dateJul 14, 1992
Priority date
Expiry dateJul 19, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C1/34
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A process for producing a silver halide photographic material that has at least one silver halide emulsion layer on a support, in which process at least 10 mg of a calcium salt per mole of silver halide is added during the period from the completion of physical ripening a silver halide emulsion to the completion of its chemical ripening together with at least one compound represented by the following general formula (I) and at least one compound represented by the following general formula (II): ##STR1## where R.sub.1 is a hydrogen atom or an alkyl group; R.sub.2 and R.sub.3 which may be the same or different are each a substituted or unsubstituted alkyl group; A.sub.1 -A.sub.6 are each a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom or a phenyl group, provided that adjacent atoms or groups may combine to form a ring; X is an anion; and n is 0 or 1, provided that n =0 when an intramolecular salt is formed; ##STR2## wherein Z.sub.1 is the group of non-metallic atoms necessary to form a 5- or 6-membered hetero ring; Q is the group of non-metallic atoms necessary to form a 5-membered nitrogenous hetero ring; R.sub.4 is an alkyl group of a substituted alkyl group; and …

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