Process of forming super high-contrast negative images and silver halide photographic material and developer being used therefor
US5766833A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1997 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Jul 8, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2200/40
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image-forming process developing a previously image-exposed silver halide photographic material with an alkaline developer containing a reductone compound as a main developing agent in the presence of a 1,2,5-thiadiazole compound and/or a 2,1,3-benzothiadiazole compound, and the silver halide photographic material and the photographic developer being used for the process are disclosed. In this case, the 1,2,5-thuiadiazole compound and/or the 2,1,3-benzothiadiazole may be contained in the silver halide photographic material and/or the alkaline developer. Super high-contrast images for photomechanical process having a gamma of higher than 15 and having no pepper and less fog can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.