Prithy, why are you stockpiling B&W developer till eternity?  Taking a slow
capsule to Mars and the Beyond?  The world ends next week so eternity will be
up toot-sweet?

The raw materials for B&W chemistry will be available as long as
civilization lasts and longer: some potash, some limestone, some
sulfur, salt, oak galls, rose hips and a jug of wine and away you go.
Actually just coffee and salt will do: develop in coffee overnight, fix in
salt water for a month or so.

To pull yourself up by the chemical bootstraps after civilization has
crashed the first steps are:

http://www.psigate.ac.uk/newsite/reference/plambeck/chem1/p01261.htm
http://www.psigate.ac.uk/newsite/reference/plambeck/chem1/p01262.htm

Which come from the really amazing site:

http://www.psigate.ac.uk/newsite/

"PSIgate is a free service that offers access to high quality
Web resources in the physical sciences; there are currently
10489 resources in astronomy, chemistry, earth sciences,
materials sciences, physics, and science history and policy [More]"

On more serious notes:

FWIW Ethol's cans do not last to eternity - five years, maybe.  One month once.

Kodak cans have lasted lots longer, though of course, some didn't, and they
aren't.

HC-110 is good for maybe 15 years.  Rodinal for 50?  PMK, if the components
are stored separately in sealed containers, 100 - 200 years: it's the
pyrogallol that's the unstable one.

The longest lived solution will be no solution: store dry powdered chemical
components in small sealed glass containers.  

Will you be using this developer during your, er, journey?

If you aren't: Open each jar, cover the opening with Parafilm and screw the
top back on.  If it is not in a glass jar then put it into a glass jar:
Wide mouth Boston rounds with Poly lined caps.

If you are: divide the chemicals before storing in hermetically sealed
containers.  Make sure the chemicals have no moisture in them - drive it
out with heat or with a desiccant.  For packaging: remember those old
injection vials made entirely from blown glass -- the nurse filed a groove
in the neck and snapped the top off -- Well do that on a larger scale,
a dose of Metol, HQ, Ascorbic acid ... in each vial.  One used to be
able to buy the vial 'blanks' that only needed a bit of work with a propane
torch to seal them.

    The answer will cost you 4 sheets of that precious Ektalure !

    Actually I'd throw T-Max and Ilford's DDX developers in as
well. Very good and stable stuff.

    Lastly, if I _really_ wanted something to last the next 50
years, I'd package dry chems for D-23 in FoodSaver (Nylon) bags. Mylar
would be even better I think.

Regards,

  John S. Douglas, Photographer -  http://www.darkroompro.com
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