Determination of silver in a photographic solution
US6405138B1 · kind B1 · utility
0Cited by
10References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1998 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Dec 17, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are provided in which silver ions are removed from a photographic fixer solution in a simple and efficient manner. The electrical conductivity of the solution is measured, which is effectively that of the fixer (thiosulphate). The electrical potential of the solution is measured between two electrodes immersed therein. A predetermined algorithm is applied to the two values to determine the silver ion concentration. If this is above a predetermined level, a silver recovery unit is activated. The measurements allow this unit to operate more efficiently than hithertobefore.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.