Digital BW, The Print

There is an excellent and reasonable current summary of information related
to paper preservation at:

http://www.clir.org/pubs/reports/pub95/contents.html

The article is called, "Preservation Science Survey --
An Overview of Recent Developments in Research on the Conservation of
Selected Analog Library and Archival Materials" written is December 2000 and
published in cooperation with the European Commission on Preservation and
Access.  Chapter 2 is devoted to paper.

One interesting note seems to say that even "acid free" paper will not stay
that way long. The article notes, in part:

"Formation of acids"

"While it is well known that papers become more acid with age, it is
generally assumed that this declining pH does not significantly contribute
to the degradation of paper. It is often presumed that only the acids
introduced in the manufacture of paper and those absorbed from the
environment are responsible for the deterioration of paper. In this context,
the term "acid-free," which in effect equates neutral and alkaline papers,
is often used to imply permanence. However, the spontaneous formation of
acids in cellulose during aging cannot be overlooked as a cause of paper
degradation."

...

"[N]eutral papers cannot remain acid-free for long. Weak acids formed in the
degradation of cellulose and hemicelluloses have generally been considered
not to pose as significant a threat as do stronger acids introduced from
acidic alum-rosin size or those formed by absorption of oxides of nitrogen
and sulfur from the environment. However, the present findings suggest that
these weak acids accumulate at a sufficiently high rate to contribute
significantly to the increasing acidity in paper as it ages. Alkaline papers
showed appreciably higher [Is this a typo?-PR] rates of accumulation than
did other papers, since the acids formed are immediately neutralized and
cannot enter into other reactions or dissipate. It was also shown that these
weak acids attach themselves strongly enough to paper, probably by hydrogen
bonding, that they are not easily dislodged from the paper matrix, even upon
airing. Because of this tenacity and because they catalyze their own
formation, these acids present a constantly escalating source of damage that
can be dealt with only through deacidification."

Paul
http://www.PaulRoark.com