I have been digitizing old family negatives, mostly 35mm from the 1970s-1990s and I'm trying to remove as much dust as possible.
I would like to be able to wash the negatives in water – of all the methods I've tried (various alcohols, blowers, wipes), this does by far the best job of removing dust embedded in the emulsion – but I've read that water washing will destabilize the dyes, and it should be followed by washing in a stabilizer containing formalin.
As I understand it, the formaldehyde in formalin locks in the gelatin around the blobs of dye in older colour films, and also has antifungal/antibiotic properties, preventing damage from mould growth.
One recommended product, Kodak Flexicolor Stabilizer III, doesn't seem to be sold any more. Does anyone know of a substitute that would do the same thing?