Good Morning Jacey,
There is a good chance the paper you are describing is heavy weight glassine. It is popular for interleaving because of it's smooth and slippery surface. While I have seen it labelled 'acid free' it does not last long, and is not recommended for long term storage. You can test the paper for acidity using an Abby pH pen, but I err on the side of replacing the mystery paper.
The decision to use something waxy-like makes me wonder if they were worried about smudging--- are any of the materials friable or easily smudge-able such as pencil architectural drawings? For the materials you describe ( posters, copies....) Elizabeth is pointing you in the right direction with mylar (polyester film) and buffered paper (Permalife Bond) for interleaving. Polyester encapsulations are great for handling large items. I would add large map folders fitted to the size of the drawers to keep things from getting inadvertently shuffled, and to give the extra support needed for handling. If you do have large pencil drawings, don't use polyester film, but rather keep them in individual paper folders that keep them from slipping and then group them so that anyone fishing in a drawer for something else is not disturbing them.
Good luck!
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Michele Phillips
Paper Conservator
Original Message:
Sent: 04-19-2016 08:22 AM
From: Jacquelyn Bonavia
Subject: Oversize Flat File Storage
Hello!
I recently began an inventory of our flat file storage cabinets. Each item (maps, posters, large photo copies, etc.) are stored between layers of a wax-paper-like material. This storage system was put in place before I began working at this museum. Does anybody have any idea what this material could be and if it is safe for the objects or should be replaced?
Thanks!
Jacey
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[Jacey] [B]
[Collections Assistant]
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