Time capsule

Judith Murphy <jamurphy [at] unm__edu> had some suggestions about time
capsules, I have to comment on this, or at least clarify some terms.

>    ... I would probably give this item
>    a static sensitive bag overwrap, but it depends on the above.
>    Our Marvelseal type bags would be better barrier-wise, and we'd
>    need to determine how much desiccant/silica gel to use inside.
>    Of course, it would be vacuum-packed unless it's very fragile.
>...
>3.  Rubber tire.  We prepared the Michelin time capsule, and each of
>    their slices was given a vacuum pack inside a Marvelseal bag.
>    Rubber does best in the absence of oxygen.

I agree with Judith Murphy's suggestions for using foil or ceramic
barrier envelopes, but I would be very cautious about using a static
dissipative bag for long term storage. I would want to be certain
that the plastics and chemicals to dissipate that static would be
very stable. I would suggest using some more effective products.

EMI's Static Intercept film is included as the inner layer of their
Polyproof 2000 foil film. This film provides a static dissipative
layer (as well as a scavenger and "sink" for corrosive gasses), and
two foil barrier layers. It was especially designed for long term
storage of very sensitive electronic parts in dangerous
environments.

Mitsubishi's RP oxygen scavenger and desiccant would remove and hold
oxygen, corrosive gases and moisture.

I often point out to brides that vacuum packaging is best for bacon
and coffee, and do not think that any precious artefacts would
benefit from long term storage under pressure. (Although paper
archives can be reduced to almost half their volume in low pressure
vacuum packages!)

Information on these products may be found on our web site
<URL:http://www.gowncare.com/~keepsafe>

Jerry Shiner
Keepsafe Systems &
Forever Yours Bridal Gown Preservation
Toronto, Ontario

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                  Conservation DistList Instance 13:19
                 Distributed: Friday, September 3, 1999
                       Message Id: cdl-13-19-003
                                  ***