Conservation Framing Techniques
How to Care for your Watercolors: Part Two
Q: I want to go to a do-it-yourself frame store to save money framing our new watercolor. Is there any need to have a professional framer do the work at several times the price?
Considering that you may have spent several thousand dollars on your watercolor, you need to take steps to protect your investment. Framing in accordance with museum standards, or "conservation framing", helps reduce the effects of atmospheric exposure on works on paper. Specifically, air pollution can contain high levels of sulfur dioxide which combines with oxygen and moisture to form sulfuric acid which decomposes paper. A professional framer pays careful attention to the frame, the glazing, the mat or spacer, the mounting and the backing.
|Conservation Framing Method
A mat is a buffer, separating the artwork from the glazing. Since paper expands and contracts in reaction to humidity and temperature, the mat allows for this movement. It also prevents mold from forming between the artwork and the glazing. The mat board should be 100 percent rag and acid-free, preferably four-ply which has good resistance against aging and the growth of fungi (mildew) which causes a condition called foxing. Cheaper board will cause mat burn, which can render the work nearly worthless; it can also be a host for parasites which then attack the artwork.
This artwork should be attached to the mat with 100 percent acid-free hinges, adhered with a water-based paste (the best hinges are made from Japanese tissue paper and are applied with cooked, gluten-free wheat starch paste). Pressure sensitive adhesives should not be used, even those that are labeled archival. Gummed linen tape should also be avoided except when necessary to hold large heavy prints. Picture-mounting corners, made of acid-free paper or polyester (Mylar), can also be used so that no adhesive comes in contact with the art. Sometimes the mat is further separated from the glazing with the use of a spacer, which may be hidden in the rabbit of the frame or may be visible as gold leaf or a decorative color surrounding the artwork.
An acid-free board is fitted to the back of the mat and a sheet of paper, also acid-free, is attached to the back of the frame, forming a seal. Wooden backings found on nineteenth-century frames contain acids and resins that stain and decompose artwork; they should be removed. Some conservators recommend sealing the artwork with impermeable material, such as Mylar, to help minimize the effects of pollutants and relative humidity. This material also protects against dust, one of the major carriers of micro-organisms. Dust allowed to accumulate penetrates the paper and cannot be removed by erasers or washing.
Now that you have paid heed to conservation guidelines, pick out the most handsome frame you can afford to set off your watercolor – nothing looks worse than an inexpensive frame! A professional has the experience to guide you in selecting an aesthetically pleasing mat and frame.