Photographic elements containing improved yellow dye-forming couplers
US6130032A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1997 |
| Grant date | Oct 10, 2000 |
| Priority date | — |
| Expiry date | Sep 26, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/30541
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photographic element exhibiting improved yellow dye stability comprises a light sensitive silver halide emulsion layer having associated therewith a yellow dye forming coupler having the formula: wherein: PA1 R.sup.1 and R.sup.2 in the formula are independently selected alkyl, aryl, amino or heterocyclic groups, each free of hydrogen bonded to the atom linking the group to the rest of the coupler; PA1 R.sup.3 is a H or a substituent; PA1 X is C, S, or P, and n is 1 or 2; PA1 each Z is an independently selected substituent group substitutable to a phenyl ring provided that at least one such group is an electron withdrawing group and s is 1 to 3; PA1 each Y is an independently selected substituent group and r is 1 to 3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.