Digital BW, The Print

>   So, does anyone know what all these various sprays and coatings
>   that are proposed here will do to print longevity ?

Here is what one authority said:

Ross Merrill, Chief of Conservation at the National Gallery of Art,
Washington D.C. (USA), in a 1997 speech regarding pastel conservation said
as follows regarding fixatives:

"Today there are a number of alternatives. Krylon Acrylic Varnish B72 is
used by conservators. This product will remain unchanged for 400 years, but
does have a tendency to saturate the surface. Grumbacher B77 varnish or
"tough film" is the same as B72, but will not saturate. Krylon workable
fixative and Sennelier fixative are both good products. One should stay away
from Grumbacher's "blue label" fixative."
See <http://www.bmi.net/knapp/iapsmerrill.html>

Rohm & Haas's Acryloid/Paraloid B72 formula is widely accepted as archival,
if for no other reason than it has been around for a long time.  Although
Krylon's B72 is not available any more (probably since Sherwin & Williams
bought the company and decided not to pay royalties), some of the Krylon
products may be very close to it.

Grumbacher "Tuffilm" is widely available at art stores and not too
expensive.  Lascaux Fixativ is the real B72 but is rare and expensive.
Krylon is the cheapest of the bunch, from what I can see.

In my fade tests, a light acrylic coating has had no significant effect.  If
applied heavily, I find the dynamic range of the print to be shortened.

We can never be sure what interactions may occur over the long haul, but my
feelings are that a light spray may be a good idea for physically protecting
the pigments somewhat from abrasion.

Paul
http://www.PaulRoark.com