I think there is no Chrome(VI) left in the processed gum print, since you wash out the sensitizer and the hardening is done by means of Chrome(VI) being photoreduced to Chrome(III). Chrome(VI) in the wash water is another issue, but I don't know exactly how to reduce Chrome(VI) to Chrome(III) because I use very little (2-3 ml 5% for each layer) and flush with plenty of water. (Makes max. 0.04-0.06g Chrome(VI) in 2-3 liters of water when it goes into the city's sewer system, not taking into account the water that gets added when flushing thru the WC. This is an extremely unsignificant amnt.)
Last edited by Loris Medici; 03-23-2014 at 08:33 PM. Click to view previous post history.
Reason: Adjusted the amnt. of Chrome(VI)