Encapsulation at Fifty Years: Results from a Survey of United States Paper Collections

Abstract A survey of the document preservation technique referred to as encapsulation was conducted of United States institutions with catalogued archives and paper collections. The purpose of this survey was to inform: an estimation of the proportion and type of materials and documents encapsulated, the popularity of various methods and the materials used for encapsulation creation, and the condition of encapsulation materials and encapsulants in collections. The survey responses provided the first data pertaining to the state of encapsulation approximately fifty years after encapsulation for preservation was formally developed. Survey results suggest that: encapsulation is well-established and highly valued in the toolbox of preservation strategies yielded by conservators and collection managers; that most encapsulation construction materials used during the past fifty years evidence few deterioration problems such as yellowing or embrittlement; that it is not a frequent occurrence that conservation treatments like deacidification, washing or the introduction of pollution sorbents is common; and that there is general satisfaction with encapsulation as a preservation method for weakened paper, maps and posters, whether the encapsulation is used in an archival or exhibition environment. Several text responses from survey participants expressed that future research on polymeric material stability and permeability may alleviate some concerns regarding future use of encapsulation.