Removal of secondary support (lining)

Very often, the primary support layer of an image lined with another support layer, usually of greater thickness and structural strength. Over time, the lining can cause issues to the primary support layer, due to the different aging process of the two supports or because of transference of corrosive products from the secondary paper or paperboard. For these reasons, the original layer of the work must be detached from the lining support. In cases where the material of the work is not water soluble but the adhesive used for the lining was water-soluble the process is easier, and can be accomplished through the controlled application of moisture and possibly some mechanical assistance.