Polypropylene

I have understood that of the three plastics that are safe for use with
paper--one of them is polypropylene.  I purchased (for personal use)
some of these pocket sheets at Office Depot; the brand called them
"Poly-Vu" but when I looked for a material type, it said "polypropylene
type." Can anyone shed some light on this?  Are they safe, or just
another mincing of words?

Dean DeBolt, University of West Florida

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                   Conservation DistList Instance 7:8
                  Distributed: Tuesday, June 29, 1993
                        Message Id: cdl-7-8-005
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