Photographic products with photosensitive layers of same spectral sensitivity and different speed
US4003744A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 2, 1974 |
| Grant date | Jan 18, 1977 |
| Priority date | — |
| Expiry date | Aug 2, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C8/08
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention relates to photography and, more particularly, to diffusion transfer process photographic film units which comprise a photosensitive element adapted to provide, by diffusion transfer photographic processing, selective dye image recordation of incident actinic radiation as a function of the point-to-point degree of photosensitive element exposure, which film unit includes a plurality of photosensitive units each exhibiting a predetermined gamma of substantially the same value and within a range of 1.1 to 1.7 and at least one of the units includes, in contiguous relationship, a first silver halide photosensitive layer comprising a particulate dispersion of photosensitive silver halide crystals, preferably silver iodobromide, iodochloride and/or iodochlorobromide crystals, possessing a first gamma and a second silver halide photosensitive layer possessing a second gamma having disposed therein dye developer which is diffusible during processing as a function of the point-to-point degree of silver halide layer exposure to incident actinic radiation. The value of the first said gamma differs from that of said second gamma by at least about 0.25, said gammas, taken …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.