Marking photographs

I recently replied to a suggestion made by Ron Stark regarding
marking photographs.  Unfortunately, I misread the query to which
Mr. Stark was replying.  I offered an opinion (negative) about
affixing Scotch #850 tape to paper based photographs.  Actually, Mr.
Stark was suggesting its possible use on RC (resin coated)
photographs.  I suspect that RC papers are considerably less
susceptible to damage from tape than uncoated papers.

That being said, I still would caution that the adhesive is likely
an acrylic and may contain plasticizers as used with soft vinyl
sheeting.  According to the Paper Conservation Catalog, #810 Magic
Mending Tape, #811 Removable Magic Tape, #415 double sided adhesive,
and #924 Adhesive Transfer Tape all use acrylic adhesives and may
contain phthalate and phosphate plasticizers.  #815 tape does not
appear dissimilar, except for the Mylar carrier.  I would be afraid
that, if present, the plasticizers may migrate through the resin
coating as they do through vinyl.

Dan Clement
Paper Conservator
Ithaca, NY

                                  ***
                  Conservation DistList Instance 9:30
                Distributed: Friday, September 29, 1995
                        Message Id: cdl-9-30-004
                                  ***