Method of forming negative dot images
US4385108A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1980 |
| Grant date | May 24, 1983 |
| Priority date | — |
| Expiry date | Jun 23, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C5/305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of forming negative dot images which comprises imagewise exposing through a contact screen a silver halide photographilic light-sensitive material of substantially the surface latent image type containing in a silver halide emulsion layer or another hydrophilic colloidal layer PA1 (a) a hydroquinone developing agent, and PA1 (b) a compound represented by the formula, R.sup.1 NHNHCOR.sub.2, wherein R.sup.1 is an aryl group which may be substituted, and R.sup.2 is a hydrogen atom, an alkyl group which may be substituted, or an aryl group which may be substituted, and thereafter processing the thus exposed light-sensitive material with an activator aqueous solution having a pH of 11.5 or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.