Paints' Mysteries Challenge Protectors of Modern Art

LOS ANGELES - In a sprawling, white-on-white lab here that looks like a set from Stanley Kubrick's "2001: A Space Odyssey," a British scientist named Thomas Learner recently lifted the top from a small box of slides, the kind that usually contain microscopic samples of bacteria or chemicals.

But this was a different kind of lab, and the slides were coated with dozens of shades of dried acrylic paint, at once as ordinary as house paint and as precious as rare isotopes. This is because the acrylics had been taken from the Santa Monica studio of Sam Francis, the abstract painter, who died in 1994 and who, like many artists of his generation, had largely abandoned the oils that had been the medium of painting for at least five centuries. Instead, he turned to their modern successors: acrylics, enamels, alkyds and many other substances that are more synthetic than organic.

The new paints, which began to emerge in the 1930s and made their way into many studios by the 1950s, allowed artists to do things they couldn't do with oil. Morris Louis used thinned acrylic to stain, rather than coat, canvases, creating an ethereal effect. Jackson Pollock used gloss enamel because it poured and dripped the way he wanted. Bridget Riley and Frank Stella both used ordinary house paints, Mr. Stella because they "had the nice dead kind of color" that he wanted, right out of the can.

But while conservators have inherited generations' worth of knowledge about oil paints, they know comparatively little about synthetics and how to protect the masterpieces created by using them, many of which are rapidly approaching the half-century mark.

Acrylics, for example, can leave surfaces softer than oil paints do, and so dust and dirt stick to them more easily. The surfaces can also be breeding grounds for mold. How should they be cleaned? Or transported? What should the temperature and humidity be in the museums where they are displayed? And what can institutions do - besides panic or weep - if real problems arise, if a deep red on a Mark Rothko painting slowly becomes a pale blue, for example, or if cracks appear in a Pollock easily worth tens of millions of dollars? (These two crises have arisen in recent years.)

In 2002 the Getty Conservation Institute here, working with the Tate in London and the National Gallery of Art in Washington, began an ambitious project called Modern Paints to answer such questions. It is only one part of a much larger undertaking for conservators of modern art, who now must deal with painting, sculpture and installation materials as strange and fragile as latex, old cathode ray tubes, whale-bone dust, fluorescent tubes, preserved sheep and at least one shaggy, taxidermied angora goat.

Dr. Learner, a conservation scientist who recently moved from the Tate to the Getty, said he began focusing on paints many years ago, partly because he believed that progress could be made relatively quickly and that the results would benefit so many museums, where paintings make up the majority of modern collections.

When he began his research in the early 1990s, he said, "It was quite a lonely time in this field." But now many conservators and scientists are involved. The Getty is in the forefront, not only because it is one of the wealthiest arts institutions in the world, with a mandate to help the entire field of conservation, but also because it does not have its own collection of modern paintings, and so does not need to focus more narrowly on its own problems.

Over the last few years, in its labs perched high in the hills of Brentwood, the Getty has brought complex technology costing millions of dollars to bear on modern paints, building up a database of thousands of kinds of pigments, solvents, chemical binders and other substances. In the process it has helped cast light not only on better ways to clean, care for and transport modern paintings, but also on the ways that artists - some, like Morris Louis, highly reclusive - worked.

On a recent tour of the lab, Dr. Learner and Michael Schilling, another Getty conservation scientist, showed off some of its machinery. This includes an infrared spectroscope that has been used to figure out the chemical fingerprints of things as varied as asteroids and illegal drugs; a device called a microfadeometer, which trains an intense beam of light - 8 million lumens per square meter, compared with about 120,000 for a cloudless day with the sun at high noon - on a tiny area of a painting to see how it fades; a hulking Atlas Ci4000 Xenon Weather-Ometer, which simulates the effects of decades of sunlight and heat in just months; and a scanning electron microscope costing more than a million dollars.

As just one reminder of the kind of lab this was, a cardboard storage box sitting on one table was emblazoned with the hand-lettered warning: "Beware!! Works of Art Below."

That morning, one Getty scientist was at work on a project that demonstrated the residual benefits of the research. A conservator trying to salvage a defaced urban mural by an artist named Peter Quezada in the Highland Park area of the city had asked the Getty to help her identify the paints used in the graffiti, so she could remove them more carefully. A chip of the graffiti no bigger than a bread crumb was examined with a spectrometer, which found that it was, in fact, two kinds of paint, each needing to be treated differently.

Nearby, almost as if by design, sat vintage paints taken from the studio of another artist famous for his murals, Jacob Lawrence. The colors - Chinese orange, olive green, golden yellow - rested on a lab table in half-squeezed tubes, waiting to be examined. And in a corner of the room behind them, another scientist subjected another kind of artist paint, a titanium white made by Golden Artist Colors in upstate New York, to a thermal analysis, in which a sample is heated in a small furnace to 1,100 degrees Celsius to "unzip the polymer chain," as the scientist, Eric Hagan, said.

Dr. Learner and Dr. Schilling, friendly, forthright scientists who throw around terms that would strike fear into the hearts of most painters and conservators - "fugitive pigments," "embrittlement," "tackiness," "yellowing" - say that their initial findings show that many modern paints, especially acrylics, are more stable in some ways than oils. But many questions remain. And paint companies, which should know more about their products than anyone else, are often not much help because they tend to guard their industrial secrets.

"The worst people to try to get information out of are the industrial manufacturers," Dr. Learner said. But even companies that specialize in paints for artists, he said, often require scientists to sign secrecy agreements if information is provided about how their paints are made.

"This is a bit of an issue," he said, breaking into a laugh, "because as a scientist you just might want to be able to tell people what you've discovered in your research."