Process for producing photographic images
US4271254A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1979 |
| Grant date | Jun 2, 1981 |
| Priority date | — |
| Expiry date | Dec 31, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/28
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A new method to produce photographic images is provided which comprises PA1 (a) imagewise exposing a photographic assembly which contains at least during the silver halide developing step, in order optionally a supercoat layer, at least one silver halide emulsion layer, a layer containing a modifiable image substance and a photobase, there being optionally one or more interlayers between each of said components PA1 (b) treating the exposed photographic assembly with an aqueous processing bath so as to provide in the silver halide emulsion layer or layers a solution or dispersion of an image substance modifying/silver halide developing compound (dymodev compound), thereby to develop the latent silver image in the silver halide emulsion(s), and PA1 (c) in the non-latent image areas allowing the dymodev compound to diffuse in a counter-imagewise manner from the silver halide emulsion layer(s) to the layer containing the modifiable image substance and there to modify reductively the image substance. Depending on the dymodev compound and modifiable image substance combination closen it is possible to obtain either a negative or a positive image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.