Thinking about the future
In conservation we need to consider future environments and situations that the objects will be exposed to, and therefore employ preventive treatment measures to ensure preservation.
Different stages of the protective backing.
A preventive conservation action undertaken for the side wings is the application of a protective backing .This is necessary for several reasons. One of them is to protect the side wings from mechanical stress and climate influences. The backing also creates a short term buffering of climate changes and decreases diffusion flow through the painting structure. Furthermore, it functions as a stabilizing support for the deformed and relaxed canvas, and reduces vibrations in the canvas during exposure on stage, during transport or handling. Finally, it is necessary to protect the back of the canvas from dirt, dust and insects.
The materials used have various properties and can be mounted in many different ways. For every object there is a different perfect backing system, so for each side wing the proportions were slightly altered to create a well-fitting support.
There are important criteria that all the backing materials applied to the strainers must have. They should allow for water vapor diffusion flow and be hygroscopic to create buffering during climate changes. They should also be pH-neutral and chemically stable, have good aging properties and be removable.
The materials chosen for the backing include polyester wadding, a hygroscopic material for buffering rapid humidity changes. Velcro ribbons attached to the to the reverse of the wadding support it, and polyester sailcloth applied on top of the wadding prevent the bending and creeping of the wadding over time. The chemically stable sailcloth is also a good dust and dirt protector. It is mounted under tension to apply even mechanical support for the wadding.
Since the sailcloth is white, shiny and semi-transparent, an outer layer of canvas is attached over it. This way there is no light reflection that could influence the aesthetical appearance of the sceneries.
The number of stainless steel screws and staples used to fasten the backing are kept to a minimum so as to preserve the original strainer bars and to allow for the backing to be easily removed.