Novel photosensitive elements and method of stabilizing said elements
US4302525A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1980 |
| Grant date | Nov 24, 1981 |
| Priority date | — |
| Expiry date | Feb 15, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C8/02
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Photosensitive silver halide emulsions for use in diffusion transfer processes are stabilized without adversely affecting spectral sensitization by the following steps: (a) spectrally sensitizing the silver halide grains; (b) lowering the pH of the emulsion from a first pH of the emulsion subsequent to chemical ripening to a pH of about 5.5 to 4.0 and/or increasing the Br ion/Ag ratio to at least 5 mg Br ion/gAg and, subsequent to steps (a) and (b), (c) adding 5-80 mg/gAg to said emulsion of a stabilizer selected from the group consisting of an hydroxy triazaindene, an amino triazaindene, an hydroxy tetrazaindene, an amino tetrazaindene, an hydroxy pentazaindene and an amino pentazaindene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.