a little more on sufite papers


jewelia (jewelia@erols.com)
Sun, 21 Feb 1999 13:53:54 -0800


i was sort of diggin' around for some stuff on ethanol for someone--didn't
find that but came across one of my paper books and looked up sulphite
process--here is a little more detail that might be of interest to a few of
you and jewelia's own thoughts about archival qualities of sulphite paper:

from Papermaking: The History and Technique of an Ancient Craft by Dard
Hunter:

"Benjamin C. Tilghman (in collaboration with his brother Richard), who also
at Manayunk, near Philadelphia, made a suitable wood pulp for paper.
Tilghman was the orinator of the sulphite method, an acid process. He began
his experiments somewhat accidentally in Paris in 1857. Tilghman's
procedure embodied the application of sulphurous acid to wood to effect the
dissolution of the intercellular matter, leaving a fibre sufficiently strong
to felt properly in sheet form....Tilghman then began experimenting and
found that a solution of suphurous acid, kept at a high temperature and
pressure, dissolved the intercellular matter of wood, but the fibres left
were red-colored and had to be bleached. Analysis showed that the
sulphorous acid had been partly converted into sulphuric acid, and it seemed
probable that the red colour came from the secondary action of the latter.
The constant pressure of an excess of sulphite of lime would prevent the
existence of the sulphuric acid, as it would immediately combine with the
lime and drive out the weaker sulphurous acid, precipitating neutral
sulphite of lime. Further research confirmed this idea, and pulp was
obtained which was pronounced by experts to be suitable for papermaking."

the story ends with the usual note--the inventor failed to commercialize his
invention loosing must of himself in the effort and earning himself a
frustrating retirement....aughh the creative life of genius!

btw: the book i quoted from was written in 1943 the first time around and is
still in print---every papermaker has one i suspect--it is not a how to sort
of book but a background book that deals with the history and practice of
papermaking from a fine art perspective--so its about good art type papers
and goes little into commercial processes. Dard Hunter died not to long ago
but is one of the principals credited with bringing papermaking back into
the fine arts--so his book is sort of a bible and he is now i guess a
papermakin' saint--so lite candles while you read it--what's better it is a
Dover Publication--bless their hearts you get about 600 pages of stuff for
about $12.00 if you're lookin for something different to read...

if archival is a great concern for you: my own guess about archival
qualities of sulphite is that --as i think it was Judy mentioned--they may
not store as raw materials forever without turning a bit--but i would
suspect the better ones would do just fine if you took care in how they were
stored. however, most of the processes we use are going to really flush
these papers out--afterall Pt prints have been cleared for a long time by
nearly scalding them the same way with acids--how it lasts depends on how
well the residue is rinsed out--i would think that most of the chemicals
these processes use and all the washing and immersion will pretty much take
care of that sort of concern--particularly if you use EDTA to clear (that is
if the paper can deal with edta--some cotton papers can't do that--depends
on what holds em together so they can withstand wetting)

what does this mean--well that once its a print and given that it was
processed with proper care and respect--makes darkroom work sound like
working in a morgue?--i don't think there is a lot to worry about
myself--but that's just me thinking--i think? i would of course be
interested in research of conservators on this account myself but wouldn't
regard any result whether good or bad as definitive--i mean they have been
notoriously wrong in their interpretations even as of late--buffered perhaps
being a huge mistake and btw some sulphite papers are buffered too so watch
out---there are too many makers, too many brands, types of sulphite papers,
varieties of processes, sources of cellulose, and each batch is different --
before it even gets to us and how we each work -- so i think the answer
ultimately is that it puts a lot more back in our lap and leaves the world a
little more of a mysterious place which leaves some hope for art and a
creative life.

and for that special person interested in making the world a better
place...I'm still lookin' for ethanol stuff...

regards,
jewelia margueritta cameroon
a psuedo paper-mache princess--now there's an art-persona i can think about?



This archive was generated by hypermail 2.0b3 on Sat Nov 06 1999 - 10:06:53