Hi Kate, paintings conservator Andrea Chevalier sent the following response:
Thin Mylar or Dartek would be fine. If the paint is thick and has a lot of impasto then Dartek would be better as it is softer than any thin Mylar. Any other packing layers could then be used against the mural. This assumes that there are no areas of flaking, detaching, etc. Those condition issues would have to be addressed before packing.
Please feel free to write again with any follow-up questions,
Rebecca
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Rebecca Smyrl
Connecting to Collections Care Monitor
Assistant Conservator for Special Collections
UNC Chapel Hill Libraries
Chapel Hill NC
(919) 962-4250
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