Method of effecting high contrast development of an image-wise exposed photographic silver halide emulsion layer material
US4756990A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1986 |
| Grant date | Jul 12, 1988 |
| Priority date | — |
| Expiry date | Mar 24, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C5/305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of effecting high contrast development of an image-wise exposed photographic silver halide emulsion layer material wherein the developing proceeds in an aqueous medium having a pH of 10 to 12 and containing: PA0 (a) PA1 (i) hydroquinone or a substituted hydroquinone, PA1 (ii) an auxiliary developing agent having a developing activity of such degree as to give when utilized in the Standard Development Test defined in the specification a relative development rate (f.sub.x) in the range of about 1-2 PA0 (b) free sulphite ions in an amount of at least 5 grams per liter of the medium, PA0 (c) an organic anti-fogging agent, and PA0 (d) a polymer containing a plurality of alkylene oxide units having a molecular weight of at least about 1500.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.