I recently got an email from Richard Monro, one of our members here and wanted to share it and discuss the medium with those of you that use it. I've just recently tried it on a few paintings and love the way it makes the paint handle, but I admit to not being as up on the safety of materials as I should be. Richard read this and wanted to give me his warning.
So - for those in the know - let's discuss this...
I have Richards permission to post his email:
Kim,
I'm inclined to go with what history teaches as we poor humans have an
unhappy tendency to not be able to stick around long enough to see
whether we are right or wrong in some of the painting decisions we make.
Ralph Mayer has written in his book The Painter's Craft: "History
teaches us that the wisest course is to adhere to the simple oil-paint
technique as much as possible, to use oleoresinous painting mediums with
restraint and to avoid complex jelly mediums" like megilp or Maroger's
medium.
And here are comments by Michael Skalka, Conservation Administrator
National Gallery of Art, Washington, DC
"Any medium mixed with a resin like damar makes it easily soluble. When
paintings in our collection have old, yellowed, damar varnish on them
and it needs to be removed, tests are conducted to see if the paint
below is sensitive to the solvent used. If the paint contains damar and
the surface is varnished with damar, conservators cannot remove all of
the varnish without removing some, if not all, of the original paint. In
those cases, the varnish cannot be fully cleaned and a layer of old
yellow varnish must remain.
I am pleased to see that painters test materials. It would be great if
only turpentine or mineral spirits removed yellowed damar.
Unfortunately, damar cross-links over time and requires stronger and
stronger solvents to remove them the longer they remain on a painting.
Again, the same solvents that will get damar to come off also attacks
paints that contain damar.
Yellowing and embrittlement are also a concern of conservators. Over
time paint lends itself to cracking as it oxidizes and ages. Damar
within a paint just tends to add to the fragility of the paint film.
You are right that Alkyds are fairy young by painting standards.
Materials scientists at the Smithsonian have done some fairly aggressive
testing with new and aged alkyd samples. They dry quickly, get quite
rigid, but then stabilize and do not grow more brittle over time. Oil
paint does. It is slow to become brittle but just keeps on getting more
brittle over time. So far, they seem to indicate that they are stable
over time. Many painters do have issues with alkyd mediums. I believe
that some formulations could be improved to decrease the browning that
occurs over time.
Our scientists are quite convinced that the physics of materials do not
get suspended because painters wish it so. The incorporation of
questionable materials like damar into paint retains its performance
characteristics. Damar continues to yellow, becomes brittle (more so
than oil paint) and becomes a nightmare to clean.
Our conservators know this to be the case as well through the experience
of caring for hundreds upon hundreds of paintings during their careers.
They know that Maroger and other mediums do not betray their bad
characteristics for a long time. (60 years is not enough time - oil
paint isn't even fully dry in 60 -80 years on a typical thickly painted
painting) Maroger (1884-1962) did not influence artists until the early
20th century so 19th century works are not affected by his practices.
However, recently, two conservators in a museum in New England examined
and studied the work of John Stuart Curry who was an avid fan of
Maroger. Many of his works have suffered through the use of the medium.
Granted, Curry was a zealot who followed Maroger's early and late
formulations. Curry's work that employed an early Maroger formula that
involved leaded oil, resin and in early versions incorporated water
based additives. These have suffered the most.
In summary, I caution painters about the use of resin in their painting
mediums because our conservators always speak of the difficulties in
cleaning and damage that is within the paint surface on works of art
that have been analyzed and found to contain damar. I believe that
getting paint to stay on canvas for a long time is no easy task. I
define a long time as 200 or more years. Lots of artists are not
concerned about longevity. For those who are, I just caution that many
of these mediums can, over a long period of time, be detrimental to the
painting. We have seen the bad practices of artists from the 18th
century, like Reynolds, presented in too many conservation research
papers to ignore the fact that experimenting with mediums and methods
can lead to disaster."
Sorry about the rant. The above is all a bit winded, but I also hope it
is helpful. These are my parting words on the subject. Each professional
must walk their own path and let history be the judge as to how well we
did. As always I remain an an admirer of your beautiful art.
Richard J. Monro
[email protected]
Hybrid Mode
