Digital BW, The Print

bjornaagedk wrote:
>
> Hi everyone!
>
> Do someone know if Epson's Archival Matte paper is 100% acid
> free?

This debate has raged on several forums, and I'm not sure we have a good
answer to the more difficult question of whether EAM can be expected to last
for long enough to be considered "archival" -- whatever that means.

(I've never seen Epson admit that they changed the name due to concerns
about pigments on EAM not being "archival."  The concern I've seen from
Epson related only to the dye-based inks not being particularly long-lasting
on EAM, and, this I believe, has nothing to due with acid in the paper.  The
EAM surface is optimized for pigments, not dyes.  On the other hand, I
strongly suspect that Epson really changed the name to avoid having to
substantiate the representation that EAM was "archival.")

At any rate, I have used one of the acid-testing pens on a number of papers.
EAM does appear to have some acid in its base.

So, it is not "acid free."

But whether enough acid in the paper to do significant, long-term damage may
be a much more difficult question. I believe EAM is made of wood pulp that
has had the lignin removed.  So, it is lignin free, and lignin is apparently
the source of most of the acid in modern wood-pulp papers.  (The older pulp
processing apparently used acid, but I beleive such processes are no longer
used for good, wood-pulp paper.)

Cotton is the purest natural source of cellulose.  So, it is the starting
material that is traditionally preferred for archival paper.  However,
whether modern, lignin-free wood-pulp can make equally-pure or pure enough
cellulose is unclear to me.  I assume that cellulose is the same chemical no
matter whether it is from trees or cotton.

I might add that the acid-testing pen appears to be easily fooled by cheap
buffering.  As such, cheap newspaper that yellows and deteriorates quickly
tests out with the pen as more acid-free than my fiber-based,
archivally-processed silver prints.

The fiber-based silver prints are probably not buffered, because such would
be inconsistent with the acid stop bath we use.  (It might be fun to see how
much a buffered paper sizzles in an acid stop bath.)  I've also read that
Epson does not buffer EAM because buffering was not consistent with the
maximizing image permanence -- which was (along with affordability, no
doubt) a primary goal of EAM.

I use EAM without much concern for the question of whether it is acid free
or not.  My conclusion is that image permanence is the more important issue,
and EAM is hard to beat on that score.  Of the papers I've tested, only
Eclipse did arguably better -- but it's blacks were not as good.  I also use
EAM because I like a smooth matte paper, and it produces about the best
images I've seen.  When these attributes are added to the fact that EAM is
just plain cheap, it's hard to find a better value.

If I found that someone was willing to pay big bucks for my prints, but only
if they were on a more "acid free" paper, I'd gladly print on Eclipse.  To
date, no one has raised the issue (or offered big bucks for the prints,
unfortunately).  So, I continue to use EAM.

Paul
http://www.PaulRoark.com