Hi Sandra,
The 7–10 days refers to the shelf life of the cardboard box, and the 4–6 weeks to the shelf life of the plastic bottles :)
The toner itself lasts forever. I replaced a batch after 10 years because there were too many suspended particles in it, and then made the new one from the opened bottles. The diluted solution was stored in glass bottles with Teflon seals. However, I must also admit that towards the end I had very long toning times, which should be avoided, otherwise the image becomes dull, though that didn’t bother me too much once it was framed. If you only want to do partial toning – i.e. you don’t want to bleach the image completely so that you still have black shadows – you should dilute the bleach further; this will slow it down. Here’s another tip to read up
on on Wolfgang Moersch’s website
. Regards, Sven.
