Patent · US Expired

Direct-positive silver halide emulsions

US3957518A · kind A · utility

2Cited by

8References

16Claims

0Family size

Assignee

Agfa-Gevaert NV · BE

Inventors

Willy Joseph Vanassche · Aartselaar, BE
Herman Alberik Pattyn · Kapellen, BE
Yvon Renotte · Embourg, BE

Key dates

Filing date	Jul 9, 1973
Grant date	May 18, 1976
Priority date	—
Expiry date	Jul 9, 1993

Classification

Technology area (CPC G)Physics
CPC primaryG03C1/48515
WIPO fieldOptics
WIPO sectorInstruments

Abstract

Direct-positive silver halide emulsions comprising fogged silver halide grains and having adsorbed to the surface of said grains an electron-acceptor have improved stability and speed when subsequent to fogging of said grains and addition of the said electron-acceptor the pH of the emulsion is lowered, preferably below pH 6.

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