Patent · US Expired

Photographic element containing an azopyrazolone masking coupler exhibiting improved keeping

US5591569A · kind A · utility

1Cited by
5References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 5, 1995
Grant dateJan 7, 1997
Priority date
Expiry dateOct 5, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C2200/06
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

This invention provides a photographic process and element where the element comprises a support bearing a light-sensitive photographic silver halide layer containing (1) a bicyclic azole coupler, (2) an azopyrazolone masking coupler, and (3) an aromatic electron-rich compound having ring substituents for which the sum of the individual Hammett sigma-para values is more negative than -0.80.

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