Direct positive silver halide emulsion and color diffusion transfer light-sensitive material therewith
US5420004A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 1993 |
| Grant date | May 30, 1995 |
| Priority date | — |
| Expiry date | Aug 10, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C8/08
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An internal latent image type positive silver halide emulsion has improved sensitivity reduction in low illuminance exposures. A color diffusion transfer light-sensitive material incorporates the emulsion and has reduced sensitivity reduction. The internal latent image type positive silver halide emulsion is prepared using a polymer having a repetitive unit derived from an ethylenically unsaturated monomer having at least one thioether structure on a side chain as a deflocculating agent to form silver halide grains and subjecting the grain surfaces to a chemical sensitization in the presence of a polymer having a repetitive unit represented by the following Formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom or a substituted or unsubstituted alkyl group and Q represents a group selected from the group consisting of groups represented by the following Formula (1) to Formula (4): ##STR2## wherein q represents an integer of 2 to 4; ##STR3## wherein R.sup.2 and R.sup.3 each independently represents a hydrogen atom or a substituted or unsubstituted alkyl group; ##STR4## wherein Z.sup.1 represents a group of atoms necessary to form a substituted or unsubstituted lactam ring,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.