Lamination

I am a conservation fellow on the Artwork Project, National Museum
of Natural History, National Anthropological Archives.  My
associate, Claire Grundy, and I are investigating conservation and
preservation options for the NAA Collection's laminated artwork.

When our research began, we assumed that the objects were laminated
with cellulose acetate, the common sheet plastic used in document
lamination.  However, Fourier Transform Infrared (FTIR) analysis at
the National Archives (NARA) has shown that the majority of the
objects are in fact *not* laminated with cellulose acetate, but a
laminate that appears to be a derivative of regenerated cellulose
(Cellophane), and also a possible match to another laminate in
NARA's FTIR library known as "Thermal X" or "Thermol X." Analysis
with solid phase micro extraction (SPME) and gas chromatography/
mass spectroscopy (GC/MS) show the predominant plasticizer in the
mystery laminate to be diethyl phthalate, a plasticizer commonly
used in cellulose acetate.

The only information we have at this time on Thermal/Thermol X is
the company's name (manufacturer? distributor?) and address that was
in NARA's sheet plastic files, handwritten on a piece of paper:

    Murray Bros. Co.
    756 N. Main Street
    Brockton, MA

If anyone in the conservation community has any information on this
particular laminate, or information on Cellophane used as a laminate
in a preservation context, we would greatly appreciate it.

Tara D. Kennedy
Post Graduate Fellow, Paper Conservation
National Museum of Natural History
National Anthropological Archives



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                  Conservation DistList Instance 14:39
                 Distributed: Monday, January 22, 2001
                       Message Id: cdl-14-39-020
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