Just Say “No” to Lamination

Lamination is a topic of discussion that comes up now and again.  So, as my first post on the MAS blog, I’ll go over the nitty gritty of it.

Lamination is encasing a piece of paper in heat sealed, protective plastic. While it is a seemingly a simple solution to many preservation issues, it is actually poised to create more problems in the long term. 

Firstly, the plastic historically used to laminate has been cellulose acetate[1].  Conservators know this as a troublesome plastic.  It becomes unstable overtime, creates acids, and starts to smell like vinegar.  This does no favours to your acid sensitive materials that are now trapped within it.  The acids produced slowly break down the structure of your artifact; weakening and causing them to become brittle. Discolouration of your paper also occurs[2].  Newer formulations of lamination plastics do not do this, however, you are still left with the adhesive that is used between the two layers of plastic; this is also acidic[3].

Lamination done badly.             

In addition to an already lose-lose situation, you have the addition of heat that is used to seal the paper in-between to two pieces of plastic. The heat could burn your paper, smear ink, or melt components of the artifact[4]. The heat and the adhesive binds the plastic to the paper; this is nearly irreversible without the assistance of a trained paper conservator.

Lamination will not slow down or stop the deterioration of your paper artifact; it may actually do the opposite. The addition of heat contributes to the rate at which chemical reactions occur; you may be increasing the speed at which your object breaks down. If there are already clear signs that your object is deteriorating, you are also now enclosing it in a place with no ventilation or avenues for harmful gasses to escape, creating a microclimate.

Ever notice that a laminated surface is really shiny? What if you decide that you want to digitize your collection? It may be really hard to scan or photograph a very shiny surface. 

This photo from a museum is an example of scanning through lamination.

The agreed upon alternative to lamination is encapsulation.  Though not appropriate for everything, such as charcoal drawings and some photographs, this method is quite helpful.  I will talk about encapsulation in a post next month.

Finally, keep in mind the golden rule in museum conservation: don’t do something you can’t undo.

Questions? Comments? Feel free to leave something behind below this post. Or contact me through email: [email protected] or 306-780-9266

References and Further Information:

[1] Grace Dobush, NARA’s Secret History of Lamination, http://www.familytreemagazine.com/article/nara-lamination-history (December 2010)

[2] Mary-Lynn Ritzenthaler, Preserving Archives & Manuscripts 2nd ED (Chicago: The Society of American Archivists, 2010).

[3] ADAH Government Records Division, The Dangers of Heat-seal Lamination, http://www.archives.alabama.gov/officials/conservlamin02.html (February 2002).

[4] Marit Muson (eds),Guidelines for the Care of Works on Paper with Cellulose Acetate Lamination, http://anthropology.si.edu/conservation/lamination/