Rapid Test for Ferricyanide Bleach Exhaustion

L. E. Varden, E. G. Seary

Ferricyanide-type bleach solutions for removing silver in certain monopack color processes become relatively inefficient upon the accumulation of but a few per cent of ferrocyanide ion. A method is given for the rapid determination of the state of exhaustion of such bleach solutions, based on colorimetric estimation of the ferrocyanide concentration. The method is sufficiently reliable for processing control, and equipment common to motion picture laboratories is adaptable.

Print ISSN
Published
1946-12
Content type
Original Research
DOI
10.5594/J12744