Patent · US Expired

Direct positive silver halide elements

US4059450A · kind A · utility

4Cited by

6References

23Claims

0Family size

Assignee

Agfa-Gevaert NV · BE

Inventors

Willy Joseph Vanassche · Aartselaar, BE
Herman Alberik Pattyn · Kapellen, BE
Erik Moisar · Cologne, DE
Sieghart Klotzer · Cologne, DE

Key dates

Filing date	Nov 20, 1973
Grant date	Nov 22, 1977
Priority date	—
Expiry date	Nov 20, 1993

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S430/141
WIPO fieldOptics
WIPO sectorInstruments

Abstract

Direct positive silver halide emulsions are provided which contain fogged silver halide grains with a layered grain structure wherein the external shell of the silver halide grains comprise up to 20 mole % of silver iodide based on the silver halide of the shell. The emulsions show improved sensitivity and produce images of improved maximum density.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.