Photographic reversal process prebleach concentrate and method of use
US5837432A · kind A · utility
2Cited by
8References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1996 |
| Grant date | Nov 17, 1998 |
| Priority date | — |
| Expiry date | Jun 27, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/40
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A conditioning or bleach accelerating solution is prepared by diluting a concentrate up to 25 times. The concentrate contains a formaldehyde bisulfite precursor salt at from 200 to 600 g/l, sulfite ions at 0 to 200 g/l, a bleach accelerating agent at from 1.5 to 25 g/l, and a metal ion chelating agent present at up to 60 g/l. The concentrate is free of sodium ions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.