Process for cleaning a photographic process device
US5198141A · kind A · utility
6Cited by
2References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1991 |
| Grant date | Mar 30, 1993 |
| Priority date | — |
| Expiry date | Nov 20, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C11/005
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Photographic processing devices such as stainless steel racks and tanks are cleaned to remove contaminants such as silver by contacting the devices with a cleaning solution comprising water, a mineral acid such as nitric acid, a soluble cerium (IV) salt such as ceric ammonium nitrate, and acetic acid. The cleaning solutions have a pH no greater than 1. The acetic acid inhibits the formation of a brown stain on in the stainless steel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.