Selenium Toner Shelf Life

I just found a bottle of Kodak Rapid selenium toner in a back corner of my darkroom shelves. I had forgotten it was there. From the store tag on the bottle, I know this is at least 10 years old. It's never been opened.

Does anyone know if this selenium toner might still be good?

Bill

It should be perfectly OK, I've kept undiluted selenium toner for at least 5 years without problem.

And how long should a mixed bottle (diluted) last on the shelf? Will it discolour when exhausted?

hmm...while we're on the topic, how long does print-flattening solution keep?

Ka said:

And how long should a mixed bottle (diluted) last on the shelf? Will it discolour when exhausted?

Click to expand...

It keeps as long as it is clear. It usually dies when the pH goes up to far and the selenium precipitates out off solution. For better keeping you can add a small amount Kodalk or borax. It will work slower this way. I started with 10g Kodalk/L and got a *very* slow toner that kept forever. I now add just 1g/L as a small pH-plus depot and I am no longer troubled with my toner dying after 3 or 4 sessions. Another trick to make selenium work faster is to add 1ml/L of Kodak brown toner. This will not or at least not visibly alter print tone but the selenium becomes much faster working as I found out when I did some experiments with homebrew combination-toners.

best

Stefan

Cheers, Stefan... that's some useful info for me. And I actually have borax. Super.
ka