The records which require repair and rehabilitation can be classified into two categories: those records which are received in a dilapidated condition and require minor repairing and those which might have been spoilt due to exposure to un-favourable climatic conditions and are brittle and fragile requiring major repair and need immediate attention. National Archives of India has a wide range of repair techniques and the type of repair can be chosen as per the condition of the records.Some of the restorative aspect of conservation includes tissue repairing, full pasting, lamination, docketing and binding etc.
The nature or restorative conservation which is used to restore a document depend on the physical condition of the record and all the above mentioned process which are being carried out in National Archives of India follow high standard of quality and the preservative materials used to undertake these process are chosen as per archival specifications prescribed for each and every material.
Conservation Research Laboratory
The Department has Conservation Research Laboratory which was set up in 1941. Since its inception, it is engaged in research and development work like developing indigenous technique for restoration, quality check of all the materials by examining physical and chemical properties of all preservative and storage materials. The Laboratory is equipped with latest models of Paper Testing Machines viz. Tensile Tester, Folding Endurance Tester and Bursting Endurance Tester etc., to facilitate examination of various kinds of preservative material. A unique process of repairing and rejuvenating documents with the help of cellulose acetate foil and tissue paper which is known the world over as Solvent or Hand Lamination process has been invented by the Department. The Laboratory has been successful in formalizing a process for rejuvenating palm leaves that have gone dry and cracking because of age or loss of flexibility. Another very significant achievement has been fabrication of a portable thermostatically controller airtight vault which is a multifunctional chamber and could be used for sterilization, vapour phase de-acidification and drying of documents, books and other material.