Photographic materials and processes comprising oxoindolizine and oxoindolizinium compounds
US4368247A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 1981 |
| Grant date | Jan 11, 1983 |
| Priority date | — |
| Expiry date | Jun 29, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/73
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Oxoindolizine and oxoindolizinium dyes are useful in photographic materials and processes as image dyes. These dyes are formed in unexposed areas of photographic materials, especially photothermographic materials, by the reaction of a photosensitive cyclopropenone with a pyridine compound. Oxoindolizine and oxoindolizinium dyes are alternatively formed by (1) reaction of a photosensitive cyclopropenone with a pyridine compound and (2) reaction of the resulting product with a color forming coupler. The photographic material is imagewise exposed and then heated to a processing temperature to form a dye image. Alternatively, the oxoindolizine and oxoindolizinium dyes are produced by imbibing at least one of the reactants into the photographic material comprising a photosensitive cyclopropenone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.