Quote Originally Posted by tkamiya View Post
Fuji Ag Guard is basically a same product as AGFA Sistan. To use, dilute it according to the instructions and soak your print AFTER COMPLETE WASH for a minute or two and squeegee the excess, then let dry. It is supposed to actively protect silver in the emulsion. I have the AGFA version of the product but rarely use it.

Interestingly enough, when used with FB paper, it prevents paper from curling so much.
Chemically, Ag Guard is very different from Sistan - the active ingredient in Ag Guard is 2-(amidinothio)ethanesulfonic acid, while Sistan is potassium thiocyanate in a wetting agent.

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