> Hello.
>
> I am reading the catalog from Artcrafr Chemicals Inc. The have listed Gum
> Arabic - solid, and something called Gum Sandorac.
>
> What is Gum Sandorac? If it is something different from gum arabic, what is
> the use of this stuff when it comes to gum printing?
Per, you raise an interesting question, because none of my books mention
"gum sandorac," as listed in the Artcraft catalog, rather "sandarac,"
which I assume is same thing. I haven't heard of it for gum printing,
though, and think it unlikely.
For a while Mike Jacobson of ArtCraft was on this list, but if he doesn't
reply, maybe someone else will. Meanwhile here's what Ralph Mayer's "The
Artists's Handbook of Materials & Techniques" says under the heading
"Sandorac" jseigel@panix.com (which is a familiar gum from early artists' processes):
"Sandarac is a resin from the Calitris quadrivalis or Alerce tree grown in
N. Africa... was widely employed for protective & decorative coatings as
well as artists' mediums...but has for many years been replaced by other
resins. It is quite hard and extrmely brittle... soluble in alcohol and
the stronger solvents, and partially soluble in turpentine, mineral spirit
and benzol...may also be dissolved in oil to make cooked varnishes....
Some investigators suspect that sandarac is the amber mentioned in
.. medieval recipes. For many years it has had little or no
industrial significance as compared with the natural and synthetic
products which have replaced it....etc."
The "cooked" might be it ... some film varnishes may still be
made by cooking various resins.... My Dicks' encyclopedia which the
gremlins have misplaced has lots of such formulas...
cheers,
Judy
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