Digital BW, The Print

Is there evidence that gelatin "encapsulation" of the print is not
consistent with extended longevity?  The reason I ask is that, since I am
also a traditional "Carbon" printer, I wonder if there is something to be
learned from those techniques which have resulted in well preserved prints
from at least the late 1800's.  One feature is that receiving paper (paper
to receive the transferred pigment image which is a suspension of pigment in
gelatin) is floated (basically immersed) in a gelatin suspension.  After
receiving the image, this "sandwich" is made permanent by soaking in
formalin solution.  I have left out a lot.  This, I believe, cross links the
protein molecules of the gelatin.  These images are about as permanent
(including the 3 & 4 color ones) that have been made.  As a pathologist I
can attest to the preserving effect of formalin.  A word to the wise -- it's
a possible carcinogen, but that concern has probably been overblown.  Any
tests been done on digital prints?  Any thoughts?  J Vee
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