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Conserving Contemporary Art… And Your Favorite Mix-Tape

This light artwork involves a lot of electronic toy dogs suspended from plastic bags. This complex installation was made by Francisco Rocha.

I spent most of today learning about what museum scientists and conservators are doing to keep contemporary art in tip-top shape. (This whole week I’m at ICOM-CC, the huge art conservation science conference currently taking place in Lisbon.)

These folks who are developing life-extension treatments for some pretty quirky art and artifacts. I’m talking about gigantic chandeliers made from hundreds of illuminated plastic bags suspended from the ceiling, each bag containing a little electronic toy dog that barks and moves its legs. Gotta love it.

Or they’re working on sculptures made from random objects covered in aluminum paint that are now degrading beneath the metal veneer. Or Nazi typewriters found at bombed Gestapo headquarters. Continue reading →

Banking On A Bunker To Save Britain’s Film

Cellulose nitrate degradation that the BFI aims to avoid with their new archive. Credit: BFI

If I had to marry an inanimate object, I would not choose the Berlin Wall as Eija-Riitta has, but I might be tempted by a bunker, possibly the Boros bunker, whose dark history has been reclaimed by great art.

So you can imagine that I was super interested in a recent Guardian

article about a new archive for the British Film Institute, which will be located on top of the site of an old nuclear bunker.

The BFI is facing what’s already a become a major problem for many who possess collections of early cinema: How do you keep 450,000 cans of film from breaking down, particularly when the film is made of cellulose nitrate, a plastic not known for its longevity?

When cellulose nitrate breaks down, it causes the release of nitric acid, which can accelerate degradation in nearby film. Eventually all the degradation results in a gooey or powdery mess where there was once a fantastic film.

The BFI’s spokesperson Brian Robinson told me that in the new archive, fragile film will be kept at -5 C, which is “down a notch” from the previous temperature (3-4 C) that the film was stored at. According to studies done at the BFI, Robinson says that the cellulose nitrate degradation will “be arrested.”

I can’t imagine that it’s ever possible to completely

arrest degradation, but I’m guessing the drop in temperature seriously decreases the rate of chemical breakdown.

Finally, Robinson says the new £12 million facility will be well-ventilated, which I presume will suck away any amount of nitric acid that has managed to percolate off the valuable film.

The PEG In Sweden’s Vasa Warship

The Vasa Warship, stuffed with PEG. Credit: Peter Isotalo.

The vessel took four years to build and was armed with the highest tech weaponry available in 17th-century Sweden, but the four-story, top-heavy Vasa warship sunk before it managed to sail a nautical mile out of Stockholm’s harbor. That was 1628.

When the ship was pulled out of the water 333 years later in 1961, archeologists found all sorts of well-preserved goodies on board, as well as a hull in excellent shape. The wood had mostly managed to avoid two major evils: Degradation via wood worms (probably because the ship had sunk when it was still brand new) and degradation via microbes (the quirky bacteria that could survive in Stockholm’s particularly polluted harbor weren’t much interested in snacking on wood).

Letting the boat dry out would have been a death sentence for the gigantic artifact, since water-logged wood tends to shrink and warp as the water evaporates away, explains Martin Nordvig Mortensen, a researcher at the National Museum of Denmark, who is studying the degradation of the Vasa’s wood. (The vessel is located in Stockholm at the Vasa Museum).

Instead of letting the boat dry out, conservators sprayed the Vasa with a polymer called polyethylene glycol (PEG) until the ship was entirely saturated. (This took 17 years of spraying!) Since PEG doesn’t evaporate away upon drying, the wood is thus stabilized against warping. (Incidentally PEG has a curious spectrum of other applications, such as in theater smoke, toothpaste, antifreeze and personal lubricant.)
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Plastics Denial Syndrome

Dutch artist Madeleine Berkhemer uses stockings in her art, which are made of nylon and spandex. Photo Courtesy of Berkhemer.

Sometime during the 1960s, artists en masse began using plastics to make art–a trend that continues today.

The problem is that many plastic polymers have a shelf life of just a decade or so, after which they begin to crumble or crack. Consider an old rubber band or a plastic bottle left out in the sun.

And just as bisphenol A leaches out of baby bottles and into the surrounding liquid, many of the components of plastic-based art seep out of the work, causing all sorts of unpleasant consequences (details below).

Furthermore, the short lifespan of plastic art is at odds with the fact that most museums want to buy art that lasts centuries or at least decades… not years.

Yet in the 1970s, 80s and early 90s, just as plastic sculptures and designer furniture were pouring in to museum and gallery collections, staff conservators were collectively sticking their heads in the sand about the inherent vulnerability of these objects… I mean, even though plastics have short lifespans, there are ways to extend them. But conservators weren’t acknowledging that plastics were problematic.

It’s come to be known as “the plastics denial syndrome” and thankfully it’s now over, says Yvonne Shashoua, a conservation scientist at the National Museum of Denmark, in Copenhagen. Shashoua features heavily in an article I just wrote about how plastics are a serious problem child for museum staff and what can be done to improve some pretty impressive bad behavior.

Yvonne Shashoua cares for a 1970s crash test dummy that is literally weeping plasticizer. Photo Courtesy of Shashoua.

Case in point: the phthalate plasticizer added to make PVC (polyvinyl chloride) maleable has a tendency to leach out, so much so that small pools of the plasticizer collect in and around the art. These plasticizer puddles are not precisely aesthetically pleasing, they attract dust and actually the loss of the plasticizer destabilizes the plastic making it vulnerable to cracking.

Then there’s this more nepharious example: Acidic gases percolate away from plastic objects made of cellulose acetate and then corrode nearby metals and textiles. For this reason conservators call cellulose acetate “the malignant plastic.”

Cases like these forced conservators to take the degradation of plastics seriously. Check out the longer article to find out what museum staff are now doing to keep plastic art and artifacts alive and as well-behaved as possible.

Two-Faced Microbes: Dirty Fungi And Cleaning Bacteria

King Tut's tomb with brown spot stains. © The J. Paul Getty Trust, 2001

Microbes can be an ugly pain-in-the-butt for artifacts.

Even if the bacteria and fungi growing on heritage buildings, frescoes, space suits and archival documents can be killed, they often leave behind some rather unpleasant stains that are really hard to clean off the sensitive surfaces of artifacts. That’s the situation in King Tut’s tomb, for example, where fungi have left behind dark brown spots on the beautifully painted walls.

Today the Harvard Gazette wrote about this issue: At the request of Egyptian heritage officials, researchers at the Getty Conservation Institute swabbed the walls of King Tut’s tomb, and sent samples of the brown muck to Ralph Mitchell, a Harvard microbiologist who specializes in cultural heritage science. Getty chemists figured out that the dark spots are actually melanin–the same pigment that builds up in your skin when you get a tan–while Mitchell’s team figured out that the fungi are dead and probably won’t be producing any more browny spots. Mitchell thinks that the fungi initially grew because the tomb was sealed before the paintings inside were dry, suggesting that the teenage king was buried in a hurry. The still-wet surface thus provided tempting real-estate for melanin-producing fungi.

Cyanobacteria growing on the Luca Signorelli frescoes in Italy's St. Brizio Chapel caused a rosy discoloration. Credit: Wikimedia Commons.

It turns out that melanin-producing fungi have also stained marble in Italian cathedrals after an ill-advised attempt to protect the marble using acrylic polymers. The acrylic on the marble attracted the staining microbes who found the plastic to be a tasty meal. But microbes will also grow on buildings, art and artifacts that haven’t received unwise “protection.” For example, orangey carotenoid pigments are often left behind by bacteria on stone buildings, Mitchell says, and frescoes have been stained rosy red due to the phycoerythrin pigments produced by cyanobacteria.

The question remains: How does one remove these unfortunate discolorations? Continue reading →

Diagnosing The Devil Inside

Using the new non-invasive technology on a plastic statue (left), the researchers were able to show that it is composed of nylon (blue) and cellulose acetate (red). Credit: Anal. Chem.

Similar to a disease, chemical degradation often advances quietly in art and artifacts, without any external warning signals. That is, until a breaking point occurs, and museum staff are suddenly faced with a faded painting or a cracked sculpture.

Like doctors who want to diagnose patients at the early stages of their illness, when treatments are more likely to work, museum conservators also want to assess the health of cultural artifacts at the initial stages of degradation, and they want to do so non-invasively–that is, without taking a blood sample.

Now Matija Strlic at UCL has just published an article about a new diagnostic tool that can visualize the internal degradation of artifacts before the damage is apparent to the naked eye.

Continue reading →