RE: [AV Media Matters] Print-through

[Graham Newton <gn@audio-restoration.com>]

Stuart Rohre wrote:

>From my own Quantegy source, Jay Zacharias of the (former) Chicago office,
>that baked a lot of tape---it was always considered a one time deal, you
>must be prepared to copy the tape to other media before 30 days or so.

I had also talked at length with Jay a few months ago, and his comments
confirmed the declining "bakeability" of the sticky tapes.  It is not just a
"one time" process, but clearly the best transfer will likely be from the
first bake job, with probable declining performance thereafter.

>We baked a 1972 tape some months back and have stored it sealed with
>dissicant to see if that arbitrary limit can be exceeded, but we always
>copy after bake.

The sealing with a desiccant makes good sense, although we should know which
has the lower threshold of absorption... the desiccant or the offending
binder... and it better be the desiccant!

I believe calcium oxide is commonly used for a desiccant... where have you
found a suitable package of desiccant to seal with tapes?
What do you seal them in and how do you do the seal?  Sources? Prices?

>Those with historical audio/video/other archives should store as cool and dry
>as possible, and hope for better chemistry.

This is probably the best and safest approach at this time.

... Graham Newton

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