Are you talking about what we call Van Dyke Brown? (Every "kallitype"
formula I'm familiar with uses an oxalate.)
> Incidentally, colour, pinks and greens, can be introduced into the brown
> kallitype by very slight variations in the processing.
Greens? How?!
> Not
> finding the colour of kallitypes sensitised with ferric oxalate and developed
> with the classic recipes, particularly pleasing, I substituted silver nitrate
> for the potassium chlorplatinate in the classic process. The results were really
>
I thought those two were the same......
> Given the need to avoid the use of strong acids, even in very weak solutions, as
> clearing agents; and the need for impractical amounts of weaker acids, eg citric
What's wrong with very weak HCL? Can't you give it weak alkaline rinse
afterwards if necessary? Anyway, EDTA worked well here, cleared kallitype
handily.
Judy