Re: where do you keep your slides?

[P3D Gregory J. Wageman <gjw@xxxxxxxxxx>]

Jim Crowell writes:

>Good to know!  How does the transfer happen?

OOOH!  I know!  I know!  ;-)

Non-archival plastics outgas their plasticizers.  "Plasticizers" are the
chemicals (usually solvents) in some plastics that make them soft.  As the
plasticizers are lost, the plastics become hard and often brittle.

The solvents deposit out on whatever is stored on, near or in them.
Outgassing of plasticizers in automobiles is what A) gives them that
so-called "new car smell" B) creates much of that hazy film that
keeps reappearing on the inside of your car's windows and C) is why
vinyl seats crack and harden over time.  Vinyl isn't stable.

Stable plastics include polyethylene and mylar (acetate).

	-Greg, who is married to a trained Museum conservationist person.


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