Digital BW, The Print

Cathy,

I think these are important issues that would benefit all of us if we could
get more expert advice on it.  Unfortunately, getting that expert advice is
hard to do.  So, I really don't think we're beating a dead horse here.  The
advantages of EAM are such that most of the people in the Piezo exchange
group that I was a member of used it.

It may be that different papers are best for different purposes.  I am
considering Museo for prints that are copies of old photos and are likely to
be mostly in dark storage. (I've done some work for the local museum, among
others, in coping old photos for preservation purposes.  So it's a serious
issue for me.)  However, I don't see an easy or certain answer, and for
display purposes, I have yet to find a better paper than EAM.

You wrote:

>... I have enough doubt about EAM paper not to get
>near it for selling archivally sound prints.

Here, I think we may need to distinguish between light fastness and very
long term dark storage.  Some use the term "archival" as referring just to
dark storage.  In the popular usage of the term, however, most think of it
as light fastness or longevity in display conditions.

Also, if an inkset has significant dye content (and Piezo appears to) the
appropriate paper may be different than for a more pure pigment inkset
(which I think MIS is).  EAM is clearly intended for pigments, not dyes.

>...tested EAM with both the Light Impressions and Lineco paper pH
>testing pens.
>Both indicated that there was a neutral or basic coating on the
>front. ...
>Tearing the paper I checked the core and it tests acid with both pens.

These are the same results I get and appear to be agreed upon.

>...it might have been manufactured as
>an acid free and lignin free paper with no added pH buffers. These
>would test slightly acid, pH = 6.0, after exposure to the atmosphere
>...
>However, there is obviously no alkaline reserve in the paper. It does
>not meet ASTM or ISO standards for permanent document paper and would
>not qualify for purchase by any U.S. Federal government agency, ...

Again, there doesn't seem to be much disagreement here.  Does the best
fiber-based enlarging paper meet these standards?  Maybe the standards for
"document paper" are simply inapplicable to other types of paper, where
buffering may have been found to be detrimental to its intended uses.

Lignin is apparently the source/reserve of acid in cheap wood-fiber paper
that most are concerned with.  As it breaks down, it makes an acid that
attacks the cellulose fibers, as I understand the issue.  Thus, a cheap,
lignin-containing paper that has some buffering in it might test "acid free"
with a pen when new, but as it gets old the lignin could pour out acid that
might overwhelm the buffering.  So, being "lignin free" appears to be
important.

> Is it going to last as long as a buffered paper? No way.

This is where the question is.  What I am saying is that the little test
pens we use are no up to the job of answering the question of long term
storage.

The member of the preservationist organization that I spoke with had no
knowledge of inkjet papers.  They were concerned with the bond papers that
most organizations use routinely.  The ISO standards are also aimed at these
types of paper that are used for documents, not inkjet paper.  For the
regular bond paper, buffering is the accepted method of trying to get them
to last longer.  It's just the cheapest way to deal with the acid.

However, it's no guarantee either.  Newsprint is even buffered and doesn't
last long at all.  And fiber-based enlarging paper is very long lasting and
does not test out as clearly acid free.  (I suspect that the processing of
the paper would make buffering useless.  It might be a good show to see what
would happen when a buffered paper hit the acid stop bath.)

It seems that Epson has found that buffering (which is very cheap) is
detrimental to the inkjet print.  It may actually be one of the reasons EAM
is so good when it comes to light fastness.  And, fading continues to be the
primary problem with prints that are intended for display.  (I think color
shifting is probably not a separate phenomena.  When I look at the results
of both, they seem to follow similar patterns.)

Also, the expert preservationist I spoke to said that some old acidic papers
have lasted.  It appears that there are sizings that can be put in the paper
that stop the destructive action of the acid on the cellulose fibers.

Unfortunately, Epson, probably to avoid sharing its R&D results with
competitors, is not giving us very satisfying answers.

At any rate, this issue is not going away.  My point is simply that the acid
pens don't answer the questions.  There appears to be a lot more to the
issue than whether a paper is slightly acidic or buffered.

To restate my current view, it may be that we should use different papers
for different intended uses.  For light fastness (display life) EAM may be
the best, for very long term dark storage, a very high quality, "acid free"
paper might be better.

Sadly, however, merely being "acid free" as indicated by the test pens
doesn't give us enough information on this second issue.  Newsprint tests
out as "acid free" (alkaline) and is the worst.  Cheap buffering can fool
the pens and not do the job.

Paul
http://www.PaulRoark.com