Patent · US Expired

Photographic silver halide elements containing filter dyes

US4877721A · kind A · utility

11Cited by
11References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 23, 1988
Grant dateOct 31, 1989
Priority date
Expiry dateAug 23, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C1/832
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A methine oxonol dye having a bis-(2-pyrazolin-5-one nucleus) substituted with PA0 (a) acyl groups in the 3 and 3' position; PA0 (b) aryl groups in the 1 and 1' position; and PA0 (c) bearing from 4 to 6 acidic substituents, each of which are capable of forming a monovalent anion provided that at least two of such substituents are other than carboxyl, is disclosed for use as filter dyes in photographic elements.

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