Process for forming contrasty image
US4237214A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1979 |
| Grant date | Dec 2, 1980 |
| Priority date | — |
| Expiry date | Jul 5, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/15
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A process for forming a very contrasty negative photographic image which comprises developing a photographic light-sensitive material comprising a support having thereon at least one layer of a negative image monodispersed silver halide photographic emulsion comprising substantially surface latent image type silver halide grains, wherein the average grain size of the silver halide grains is 0.7 micron or less, with the silver halide photographic emulsion containing a binder in an amount of 250 g or less per mol of silver halide, and at least one hydrographic colloid layer containing a compound represented by the following general formula (I): EQU R.sup.1 NHNHCOR.sup.2 (I) wherein R.sup.1 represents an aryl group and R.sup.2 represents a hydrogen atom, a phenyl group or an alkyl group having 1 to 3 carbon atoms, in the presence of a compound represented by the following general formula (II) or (III): ##STR1## wherein Z.sup.1 and Z.sup.2, which may be the same or different, each represents an atomic group necessary to complete a thiazole ring or a selenazole ring; R.sup.3 and R.sup.5 which may be the same or different, each represents an alkyl group which may be substituted or an alk…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.