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40 desIGnInG WItH PoLYMeRs
elements39 Issue 2|2012
The world’s museums house priceless works of art.
New PLEXIGLAS® Optical HC put these exhibits in the
best possible light, permanently protecting them from
damage and depreciation.
YeaR afteR YeaR, millions of people flock to museums to marvel
at the artifacts of past cultures or the works of contemporary
artists: Drawings and paintings, sculptures and documents,
historical garments, consumer items, and weapons. Few of these
visitors are aware, though, that the professional protection
of the exhibits is just as vital as their presentation. Indeed,
Evonik is making a major contribution here. The company’s new
PLEXIGLAS® Optical HC, with its abrasion-resistant coating,
protects priceless exhibits against mechanical or chemical damage,
prevents them from yellowing, presents them without any
color distortion, and makes it possible to individually design display
cabinets, boxes, protective panels, and transport packaging.
One of the greatest challenges in exhibiting paintings, documents,
and art treasures is in achieving the optimal lighting. Ideally,
structures, colors, and details should be seen undistorted,
but the UV radiation in natural light often damages historical
material. This causes sketches, watercolors, and garments to lose
their original colors, pages of books to turn yellow and thin out,
and canvases and other materials to become brittle.
no color distortion
Protective measures
for treasures
This is why PLEXIGLAS® contains an integrated chemical UV
filter that filters out damaging high-energy radiation. At the same
time the material, with a transmission of 92 percent, is highly
transparent in the visible region of the spectrum, allowing
a clear and sharp view of the details and the structures of the
exhibits with colors remaining true: The polymer avoids color
distortion such as caused by, for example, the greenish tinge of
float glass.
A large number of archives and museums have already discovered
this amazing plastic for themselves. The U.S. National
Archive transported seminal U.S. historical documents in cus-
tom-made PLEXIGLAS® display cases throughout the country
for a traveling exhibition. The DeBeers Diamond Museum in
Johannesburg, South Africa, displays historical documents in
non-reflecting PLEXIGLAS®. In the Landtag (parliament) of the
German state of Hesse, sketches by the architect Georg Moller
were exhibited behind PLEXIGLAS® to mark the 150th anniversary
of his death. The slight curve of the glazing showed off the
sketches to best advantage.
But transmission and UV absorption are not the only requirements
for the professional protection of museum treasures. Visitors
leave behind their tracks: Fingerprints, sweat, and abrasion
due to zippers or handbags.
This is why the new PLEXIGLAS® Optical HC is equipped
with a special surface coating, ensuring excellent resistance to
mechanical impact and cleaning chemicals. This protects display
cases and picture glazing against distracting chips and scratches,
and the surface quality remains unchanged even with heavy
wear. A comparison with uncoated acrylic shows that the coating
increases abrasion resistance by a factor of ten, and more
than doubles the hardness.
well protected against chemical attack
Fingerprints and mechanical impact are unavoidable when
visitors come close to exhibits. Targeted chemical attacks on
artworks are risks of an entirely different dimension—but
PLEXIGLAS® Optical HC offers effective protection even against
these. Thanks to its surface coating, the material is resistant not
only to abrasion but also to chemicals. This makes it easier for
galleries and museums to meet their generally very stringent
security requirements.
But protecting artworks does not begin in the museum or
gallery. The art market is booming, and touring exhibitions give