Conservation: works of art on paper
Watercolours, prints and drawings are all works of art on paper. Although they look quite different, and are made with different media, it is wise to treat them the same - as fragile, sensitive and easily damaged.
Always handle unframed paper items with clean, dry hands and carry them on a support. Never carry them dangling by one corner.
It is easy to damage a painted, drawn or printed image. Therefore, store your unframed works in smooth paper folders, preferably of acid-free paper or a paper such as neutral glassine. If possible, store them flat. Rolling and unrolling will damage brittle papers and delicate images.
Plastic folders such as polyester (Mylar) should not be used for storage as a build-up of static can cause a flaky or chalky medium to transfer to the plastic. This is certain to occur with unfixed charcoal and pastel drawings, which are best framed or stored alone in a drawer. Nothing should be allowed to touch the surface of such items. Avoid fixing pastels with hair spray or artist's fixatives, which can alter their appearance.
When conservation framing an art work on paper, the item should be sandwiched in a mat consisting of a mount-board window and a backing board. Both boards should be 4-ply (or heavier), acid-free, buffered, conservation mount board. Chipboard, masonite or any other timber sheeting must not be used behind the artwork. As it is important that artwork does not touch the glazing, ensure that a window mount separates them.
The artwork should be hinged to the backing board with gummed paper or paper tabs with a water-soluble adhesive. The tabs are attached to the top of the back of the artwork. Adhesive tapes, heat-set tissues or contact cements are not acceptable in conservation framing.
Glazing can be acrylic (Perspex or Plexiglas) or glass. Acrylic is lighter and won't break as easily as glass. We recommend using ultraviolet-absorbing Perspex 9 or Plexiglas 201, if possible. However, as acrylic develops static, it can damage pastels and other powdery media.
The frame should ideally have a deep rebate behind to allow air movement. Make sure the hanging method is strong enough to support the frame's weight. If you deal with a framer who offers conservation framing, expect him or her to satisfy the above criteria.
When displaying art on paper, never hang it where it catches direct sunlight or bright light. Light can fade coloured papers and coloured media, and can cause darkening of white papers. Take into account the special sensitivities of each item: a felt-tip pen drawing on butcher's paper would be very sensitive to light, a charcoal sketch on good-quality watercolour paper is much less so.
It is important to allow good air circulation behind a framed work to avoid a build-up of damp. It is dangerous to hang works above heaters or fireplaces where rapid changes in temperature occur. This can lead to cycles of drying out and condensation within the sealed frame.
Paper Conservators at the Australian War Memorial contributed the information. If you need more information, ring the Conservation Section on (02) 6243 4418 and ask for a Paper Conservator.