Silver halide photographic light-sensitive systems
US4925832A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1988 |
| Grant date | May 15, 1990 |
| Priority date | — |
| Expiry date | Oct 31, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/15
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A silver halide photographic light sensitive emulsion containing a hydrazine of the general formula EQU R.sup.3 -NR.sup.4 -NR.sup.5 -G-X (I) in which PA0 R.sup.3 represents an aryl group, PA0 one of R.sup.4 and R.sup.5 is a hydrogen and the other is selected from hydrogen, aryl sulphonyl and trifluoroacetyl, PA0 G represents carbonyl, sulphonyl, sulphoxy, phosphoryl or an N-substituted or unsubstituted imino group and X is a moiety such that at a pH in the range of 9.5 to 12.5 in the presence of an oxidized hydroquinone a cyclization reaction takes place cleaving the moiety -G-X from the remainder of the molecule and forming a cyclic structure comprising atoms of the moiety -G-X.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.