From: Katharine Thayer (kthayer@pacifier.com)
Date: 07/25/01-02:49:19 AM Z
Katharine Thayer wrote:
I recommend against Alizarin Crimson, because even in its modern [Ed
note: "modern" here used loosely since the synthetic version of the
pigment was formulated in 1826] formulation it gets the lowest lightfast
rating from every manufacturer,
including (last I checked) W&N.
Judy Seigel wrote:
>
> Oh my.. well...
>
> Some of this discussion about colors for gum seps has been -- um, how to
> say this tactfully, well, tactlessly -- *useless,* in fact less than
> useless, because just naming a "pigment" without the manufacturer's name
> attached is about like saying "red." Worse actually -- "red" doesn't claim
> specificity, and "alizarin crimson" does.
Hi all,
Sorry this is so long after the fact, but I'm trying to whittle my inbox
down to size and came across the above which requires a response because
it's such an important issue for gum printers working in color:
My use of the term Alizarin Crimson was exactly specific, referring to a
specific pigment which goes by the commonly-accepted name of Alizarin
Crimson, the scientific name of dihydroxyanthraquinone, and the color
index number PR83. (Some sources use the designation PR83:1 to
distinguish the synthetic form from the natural form, others do not,
but it doesn't really matter because neither the synthetic nor the
natural version of the pigment is lightfast. Some sources call the
natural form Rose Madder Alizarin, others call both forms Alizarin
Crimson. They are chemically the same material.) The pigment is rated
Lightfast IV by the ASTM, meaning very poor, and it doesn't matter what
lightfastness rating the manufacturer puts on it, anyone using this
pigment is taking a risk with the permanence of their work..
Here's some manufacturers whose paint labeled Alizarin Crimson is made
from the fugitive pigment PR83, Alizarin Crimson (I won't bother naming
all the paints with names like lake and madder and carmine and etc that
use this pigment except to say don't buy paints with names like that
unless you're sure of the pigment. Alizarin crimson isn't the only
fugitive red pigment, by the way, but it's the one I'm most concerned
about because so many people seem unaware that it's a problem):
Some Paints Made From PR83 Alizarin Crimson pigment:
Daniel Smith Alizarin Crimson
Rowney Alizarin Crimson
Winsor & Newton Alizarin Crimson.
M. Graham & Co Alizarin Crimson
Utrecht Alizarin Crimson
Rembrandt Alizarin Crimson
Old Holland Alizarin Crimson Lake extra
Schmincke Alizarin Crimson
Sennelier Alizarin Crimson
Grumbacher Alizarin Crimson
Hunts Alizarin Crimson
Maimeri Alizarin Crimson
Permalba Alizarin Crimson
The only paints labeled Alizarin Crimson I can find that don't use PR83
are:
DaVinci Alizarin Crimson
American Journey Alizarin Crimson (American Journey?)
Shiva Alizarin Crimson Hue
These three paints are made from PV19 Quinacridone Violet.
Gum printers looking for a substitute for Alizarin Crimson have several
other pigments, most notably the pigment PV19 which comes in two forms:
quinacridone rose and quinacridone violet, and goes by various paint
names. For example, Linel carries a Permanent Carmine, a Thalo Crimson,
and a Ruby Red that are all made from PV19. Other PV19 possibilities
among many are permanent rose by Winsor & Newton or Rowney, quinacridone
rose by Daniel Smith or M. Graham, and various quinacridone reds.
Winsor & Newton have a Permanent Alizarin Crimson and a Permanent
Carmine made from the pigment quinacridone pyrrolidine, no color index
assigned yet, which is considered lightfast by experts I trust, although
it hasn't been rated by ASTM. The permanent carmine is made from the
pure pigment; the permanent alizarin crimson has PR206 (sometimes called
quinacridone burnt orange, sometimes called quinacridone maroon) added.
I understand that Holbein also has something called Permanent Alizarin
Crimson, but I haven't been able to find the pigment for that.
How can you find out what pigment is in the paint you buy? The brands I
buy carry the color index number and the scientific name of the pigment
on the tube. If you prefer a brand that doesn't do that (in my opinion
they all should) you should still be able to get a chart from the
manufacturer that gives the specific pigment(s) contained in any tube of
paint. Several manufacturers carry such charts online.
Katharine Thayer
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