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“Vita Brevis, Ars Longa!” is a quote from the ancient Greek physician Hippocrates. It can be translated as “life is short, art is long”. If you have hopes that your artwork will outlive you (as I do) then the issue of permanence becomes important.

Art instruction in the second half of the 20^th century was accompanied by not only the diminution of basic painting and drawing instruction but also training in sound painting practices. The result has been a nightmare for conservators. While masterworks painted in the 1500s and 1600s remain in good condition, some pieces painted in the 1950’s and 1960s are falling apart.  Cracking, “cupping,” and paint loss can be seen in paintings that are only a few decades old. Why? And more importantly, what can we do to prevent this?

For a more in-depth discussion of this problem I refer you to the Natural Pigments blog http://www.naturalpigments.com/blog (The source for this photo.)

But here’s the quick and dirty.

An oil painting is a complex composite of materials that interact with each other over a long period of time. There are several components: the support, for example, stretched canvas; the ground, often an oil or acrylic primer; the paint itself; solvents like turpentine; mediums like Maroger or Liquin; and varnishes like Dammar. The problem is that each of these components expands and contracts at varying rates; cracking is the inevitable result.

The number one offender is the support. Stretched canvas is hygroscopic (readily absorbs and gives off moisture) and flexible; the paint film is not. Think of a layer of peanut brittle on Saran Wrap…Not the most archival arrangement! I’m starting to use rigid supports from Raymar (Claessens linen adhered to an aluminum substrate).

The number two offender is the pigment in most white paint. The old masters used white made with lead carbonate. Titanium is more brittle and zinc oxide is the worst of all. Unfortunately, most paint manufacturers add zinc to their white because it’s cheap and bright. Artists also worry about the toxicity of lead (wear gloves and don’t eat it).  I now use lead white. You can’t go by the name; you need to look at the pigments listed on the tube. Lead is PW1; zinc is PW4.

The other major offender is the medium. If resins are added to a medium they weaken the paint film, especially organic resins like Dammar, copal, or mastic. (They can be used in a final varnish.) I rarely use any medium, and if I do it’s one part linseed oil to three parts Gamsol to minimize any impact to the paint film.

May all our paintings “live long and prosper.”