Protecting Paper
March 2008
Watercolors, prints and photographs are among the most popular collecting categories in the United States, if not the world. Prices range widely, but works on paper are very approachable at the lower end and are, from a cost perspective, easy entry categories, in the jargon of the art world. They are easy to buy and easy to enjoy, but need special care to prevent damage from the quotidian hazards of light, humidity and acid. They are more vulnerable than works on canvas or panel, and are most frequently and beneficially framed under glass. A good framer and a good paper conservator should be in your address book. Following is some expert advice on how to properly maintain your works on paper.FRAMING PROTECTS. Protect your art on paper by framing it under light-filtering UV (ultraviolet) protective glass, which is available at any good framing shop. Some collectors opt for the lighter weight of UV-resistant clear acrylic, which can take a blow without shattering (good if you live in an earthquake zone) and will offer more protection in a fire than glass, which will heat-shatter quickly and expose the art. However, glass should always be used to frame pastels or charcoals because the build-up of electrostatic charges in acrylic will eventually disturb the powdery mediums, which don’t bind well to paper.
Mat boards, by providing separation, prevent the artwork from adhering to the protective front glass or acrylic, which can happen in very humid environments. The sealed back is a barrier against pipe-bearing or outside walls that convey moisture and transmit temperature changes. "To prevent the frame itself from resting directly on the wall, especially an outside wall, buy spacers at a hardware store or—a trick I suggest to my clients—slice a wine cork into quarter-inch discs and attach one to each back corner with Elmer’s glue," says Martina Yamin, a New York–based conservator of works on paper. Whenever possible, hang works on paper on interior walls.
ACID CONTROL. Ordinary paper contains acid that will eventually cause discoloration and brittleness. Art on paper should always be mounted on and matted with acid-free backing paper or four-ply museum board (which is acid-free cotton rag). "Because glues will likely damage the paper," says Yamin, "the preferred adhesive for attaching the art to the backing is archival hinging tape or archival paper hinges, which are made of Japanese paper with soft edges. These are attached with wheat starch paste, which creates a strong bond." David Chandler, chief conservator of works of art on paper at the Chicago Conservation Center, reports that conservators cook—literally—and strain this paste several times to make it very fine, smooth and malleable. It provides high adhesion yet is removable. For collectors who want nothing attached to their art, the alternative is Mylar photo corners, which are acid-neutral and won’t discolor.
TEMPERATURE AND HUMIDITY. Recommended guidelines suggest maintaining room temperature between 68 and 70 degrees Fahrenheit (up to 75 degrees is tolerable), and humidity in the range of 40 to 50 percent (up to 55 is acceptable, but is still less than ideal) to help deter mold, mildew and foxing—those stubborn, unattractive rust-like spots. Consider using dehumidifiers in damp environments and humidifiers in drier settings, alternating seasonally if necessary.
For these reasons, do not hang art over a fireplace, a heating or cooling unit, or in bathrooms or kitchens. If your art should be soaked by a storm, immediately blot off moisture with a paper or cloth towel. Carefully disassemble the frame and move the art to a space that is light and air-conditioned or that has fan-circulated air. Then get it to a professional conservator as quickly as possible.
The important thing is consistency. "Because paper reacts greatly to changes in both temperature and humidity, aim for as little fluctuation as possible," says Chandler. "Photographs are perhaps the most susceptible to humidity changes. They can warp and even shift position in the frame under the most dramatic circumstances."LIMIT LIGHT. UV rays in both natural and electric light cause fading and sometimes cracking, so UV-protective glass is essential. Los Angeles paper conservator Robert Aitchison points out that "in a room with bright, light walls, even artwork only indirectly lighted by the sun can be damaged by ultraviolet light bouncing off walls. UV glazing begins to lose its effectiveness after 7 to 10 years, so keep track of its age and reglaze when necessary." Katja Zigerlig, collections underwriting manager at AIG, suggests, "Check the placement of your artworks throughout the year. A wall without sunlight in the summer may be in direct light in the winter."
Although it is not always possible, it’s prudent to hang your art in windowless areas or rooms only dimly lit by indirect sunlight. Consider using UV-filtering film for your windows, especially if your home has a lot of exterior glass.
"Artificial light can be destructive," says Vivian L. Ebersman, director of art expertise at AXA Art Insurance Corporation. "Don’t illuminate a work on paper with a picture light attached to the frame, as both the light and the heat of the bulb are harmful." Beware of halogen lamps, which emit high levels of ultraviolet light; if used, they should be fitted with a UV filter. Recessed lighting is good. If it’s feasible, rotate artworks in and out of storage every few months to limit the cumulative effects of light exposure, as many museums do.
STORAGE. Even if they’re not hanging on the wall, works on paper require care. Store unframed artwork horizontally, separated by acid-free paper. Erica Hartman, writing for the Chubb Collectors Newsletter, suggests storing the works in clear Mylar envelopes or in acid-free folders placed in acid-free (pH neutral) storage boxes. Never store artwork in the places where people usually store things, such as garages, basements and attics, unless the space is climate-controlled. In short, apply the same care and caution as with a framed piece.
This may sound like a daunting list of dos and don’ts, but most of these prescriptions and proscriptions come down to common sense and moderation. Los Angeles paper conservator Mark Watters reminds us that "optimal care of works on paper is really a matter of variables and degrees, and we can’t always control all the factors. But the more you can, the safer you are." High-quality paper, controlled temperature and moisture, the reduction of acid and ultraviolet light, the help of a good framer and conservator—each step will help preserve your art.
Roberta Maneker, an Art&Antiques New York correspondent for more than 10 years, has held executive positions at Christie’s and Phillips de Pury&Company.
AIG Private Client Group
aigpcg.com
Aitchison & Watters Inc., Los Angeles
323.957.1700
AXA Art Insurance Corporation
212.415.8414
Chubb Personal Insurance
chubbcollectors.com
Martina Yamin, New York
212.532.6957
Museum Conservation Institute, Smithsonian Institution, Washington, DC
301.238.1240 si.edu/mci
The Chicago Conservation Center
800.250.6919 chicagoconservation.com