Photographic color developer compositions
US4482626A · kind A · utility
36Cited by
4References
30Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1984 |
| Grant date | Nov 13, 1984 |
| Priority date | — |
| Expiry date | Mar 30, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/39208
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Photographic color developer compositions containing a primary aromatic amino color developing agent and an hydroxylamine are stabilized by incorporating therein certain polyamino stabilizing agents, such as N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid. Decomposition of the hydroxylamine, in the presence of heavy metals such as iron which act to catalyze the decomposition, and resultant formation of ammonia is effectively prevented by the presence in the developer composition of such stabilizing agents. Undesirable precipitate formation is also effectively avoided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.