Patent · US Expired

Photographic spectral sensitizing dye

US4940657A · kind A · utility

3Cited by
4References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 19, 1989
Grant dateJul 10, 1990
Priority date
Expiry dateJan 19, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C1/12
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Disclosed is a photographic spectral sensitizing dye represented by the following formula (I), (II) or (III): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.5 or R.sub.7 each represents an alkyl group, an aralkyl group or an alkenyl group, R.sub.4 and R.sub.6 each represents an alkyl group, aralkyl group, an alkenyl group or an aryl group, L.sub.1 -L.sub.22 each represents a methine group, Z.sub.1 -Z.sub.4 each represents a group of atoms necessary to form a 5- or 6-membered nitrogen-containing heterocyclic ring, X.sub.1.sup.- and X.sub.2.sup.- each represents an acid anion and l, m, n, p, q, r, s, t and u each represents an integer of 1 or 2. Silver halide photographic emulsion containing the above sensitizing dye is also disclosed.

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