Nondiffusible 6-arylazo-3-pyridinol
US4358404A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 1981 |
| Grant date | Nov 9, 1982 |
| Priority date | — |
| Expiry date | Feb 23, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/159
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Nondiffusible compounds are described having a releasable 6-arylazo-3-pyridinol magenta dye moiety or precursor thereof having the formula ##STR1## wherein: (a) R represents hydroxy or amino; PA0 (b) R.sup.1 represents hydrogen, a hydrolyzable moiety or CAR; PA0 (c) G represents carboxy; a hydrolyzable ester or a sulfamoyl group; PA0 (d) CAR represents a ballasted carrier moiety capable of releasing the diffusible 6-arylazo-3-pyridinol dye moiety or precursor thereof under alkaline conditions; and PA0 (e) n is 0, 1 or 2, with the proviso that when n is 0, then R.sup.1 is CAR; and wherein the phenyl ring is not substituted with a nitro group. These magenta dye-releasing compounds are used in photographic elements and diffusion transfer assemblages. The magenta dye moiety or precursor thereof is released as a function of development of a silver halide emulsion. The dye moiety then diffuses to an image-receiving layer where it forms a highly stable, metal-complexed dye transfer image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.