Do you own a work of art on paper that was framed more than 30 years ago? Then it was most likely not framed archivally, for much of the expertise that we have today was simply not available at that time. Even if your work on paper has been framed more recently, then you still cannot be sure that the framing was done properly unless you know that it was handled by a reputable framer who uses only archival methods.
Just what is archival framing and why is it crucial for works of art on paper?
Watercolors, prints, drawings, photographs, rare documents, collages—all are usually works on paper and all need to be properly framed to ensure their longevity for generations to come.
Archival framing refers to materials and methods that promote the long-term health of an artwork on display by controlling environmental threats to its well-being, such as humidity, temperature, light, dust, etc. All materials used in archival framing must be conservation grade and the techniques employed completely reversible, leaving no trace when the artwork is removed from the framing package.
These are the top issues to be aware of when assessing archival framing of your works of art on paper:
Works on paper need to be secured to a backboard for framing using the most reversible and least invasive method possible. Archival hinging is often the preferred method. Hinges should be made of acid-free Japanese paper and applied with non-acidic and reversible methyl cellulose or rice starch paste. Hinges are applied to the top edge of the artwork, so that the paper can expand and contract as it responds to fluctuating temperature and humidity levels. Two main types of hinges are used in archival framing: the t-hinge and the folded hinge. The t-hinge has a “tab” that extends beyond the edge of the paper. Another strip of acid-free paper is then placed on top of the tab and is attached to the support material. An overmat that covers the edges of the paper must be used to conceal this type of hinge. The folded hinge is more discreet, because it is applied entirely under the edge of the paper. Here, a small strip of acid-free paper is folded in half to form a sort of “tent.” One half of that “tent” adheres to the back of the artwork and the other to the mounting board. This method works well when an artwork is floated, that is, when the entire paper is visible.
In some cases, there are other archival ways to secure an artwork to its backing. One is filmoplast—an archival quality, self-adhesive tape that is used when the moisture of an adhesive such as rice starch paste might cause distortions in the paper. Filmoplast can be used when a “float” is desired.
Acid-free photo corners are another simple, effective way to safely attach a work on paper that is structurally stable and relatively lightweight. Rag paper and Mylar mounting strips are very effective in mounting larger, heavier works on paper, or works that have an irregular or fragile structure. While they have the same “tent” shape as folded hinges, they are much stiffer and function somewhat differently: only the strip itself is attached to the support board, and the artwork is cradled in the moisture and acid-free environment within the “tent.” Photo corners and mounting strips are especially advantageous for fragile photography media, because these hinging methods attach the work securely without applying any adhesives to the paper.
Mounting is not the same as hinging and generally refers to attaching the artwork to a support using some sort of adhesive over the entire verso of the paper. This method is in most cases not a reversible or an archival method and is not advisable. Linen and most pressure-sensitive tape —even those advertised as “archival”—are also not recommended, because they are not easily reversible and can damage an artwork.
Acidic materials create big problems for works of art on paper. Acid-free, 100% cotton ragboard, buffered with calcium carbonate should always be used for top and bottom mats. The medium of some photographs, however, is sensitive to calcium carbonate and therefore in these cases matting should be non-buffered. Silk, linen, or French paper mats can be used, but they should be made using acid-free materials over ragboard and backed with an additional two-ply ragboard barrier. It is most important that either a rag mat or fillets provide a space between the art and the glazing. Humidity can cause damage to the surface of the art if the paper is in direct contact with the glazing. A layer of foamcore, taped or covered with a dust cover, will protect the back mat and guard against infiltration of impurities.
Paintings are traditionally varnished for protection and do not need glass, but some type of glazing should be used when framing any work on paper to protect the fragile surface. To avoid damage from light, UV filtering glazing products are recommended whenever a work on paper is exposed to strong light. Sunlight is the most damaging, followed by halogen lighting, while incandescent lighting causes the least damage. Watercolor, brown ink, some pens, and markers are very light-sensitive mediums and should be framed with UV protection when exposed to any light. Pastel and charcoal drawings should be framed using glass or a plexiglass that has anti-static properties. It is also recommended that UV glazing be replaced every 15 years or so.
Are you not sure who framed your work on paper or when? Check for the following warning signs and consult a reputable framer or paper conservator:
● A brown, cardboard-colored bevel on the mat is usually evidence that the mat is not acid-free; the acidity could be causing a discoloration known as “mat burn” to develop on your artwork.
● Faded or discolored matting usually indicates the presence of acidity.
● An overall brown discoloration on the artwork can mean that light damage has occurred. This may also indicate a permanent fading of the pigments that cannot be corrected.
● Brown stains on the artwork may result from the use of improper acidic tapes or damaging adhesives on the verso.
● Scattered brown spots can be caused by foxing or mold due to contact with an acidic cardboard backing and excessive humidity.
● If there is no mat and the artwork is fit directly against the glass, then humidity may cause the surface of the art to develop irregularities and the artwork can even become adhered to the glazing.
● If there is no label indicating a UV filtering product, then you can assume it has not been used.
Do you have questions about an existing frame or mat for your work of art on paper? Do you need a new frame for a valuable watercolor, print, drawing, or photograph? Lowy’s master conservators and framers are here to help—please contact us.