I have tried using this solution on some platinum/palladium prints. Used
after the final wash & dry, the print brightener can be used to achieve a
cooler,neutral print tone. Sprint claims that this treatment will result
in normal UV light to be reflected as visible white light. This makes the
paper look much whiter, and is also said to inhibit UV light from reaching
the print.
After using print brightener the paper (Arches Platine) has a very white
(almost bluish-white character) like a "Super White" mat board. Sprint
says that they use the same chemical used by some manufacturers of
silver-based photo paper to get brighter whites. This solution is far
more effective than any developer or sensitizer change for getting cooler
print tones. A print of nearly pure palladium (I haven't tried
palladium-only yet) looks very much like a pure platinum print after
treatment.
These are only preliminary results - I still need to contact the company
to press them on the possible consequences of the solution on the
archivalness of a print.
In the end I chose not to use the solution because I like the warm tones
I get without it. However, it's good to have the choice.
David Fokos