Ilford IF-15 Potassium Alum Acid Hardener-Fixer
This hardening fixer is intended for use with films and plates.
Sodium thiosulphate (hypo), cryst . . . 320g
Sodium Silphite, anhyd . . . 30g
Boric Acid, cryst . . . 10g
Acetic Acid, glacial . . . 18cc
Potassium Alum, cryst . . . 25g
Water to make . . . 1 litre
Dissolve the hypo in 500cc of hot (52C or 125F) water. Upon cooling, add the sulphite.
Dissolve the boric acid, acetic acid and alum in 150cc of hot (52C or...