Removing tape from negatives

I am looking for an appropriate and safe way to remove tape and the
sticky residue left behind on negative images that were used in
printing a publication.  The negative images are on a type of thick
mylar (I believe) and are masked with the red tape typically used in
printing publications.

Has anyone used successfully, or unsuccessfully, either of the
following products?

    Un-du Sticker and Tape Remover

        I've investigated web sites that advertise this and
        according to several different sources Un-du passed the
        P.A.T. at the Rochester Institute of Technology and was
        found to be acid free by Duke University.

    PEC-12

        Light Impressions carries this "archival photographic
        emulsion cleaner" and I believe it has been tested by the
        IPI and blessed.

Is either one recommended or is there a better product available of
which I am unaware?

Mary McKay
Lead Processing and Photographs Archivist
Richard B. Russell Library for Political Research and Studies
Main Library, University of Georgia Libraries
Athens, GA 30602-1641
706-542-0627
Fax: 706-542-4144


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                  Conservation DistList Instance 15:54
                 Distributed: Tuesday, February 5, 2002
                       Message Id: cdl-15-54-034
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