RE: [AV Media Matters] acetate tape binder-lets evaluate its acid ity level.

[e.ha.zwaneveld@nfb.ca]

Greetings,

Jim Wheeler stated:

>I have several tapes from 1953 that are playable with a lubricant and they
>have had a vinegar smell for several years.  The smell of vinegar indicates
>that a chemical process is ocurring but it appears that it is not as fast as
>we have been told.
>Jim

Comment:
It is not news to read that triacetate tape appears to degrade at a
slower pace than magnetic sound film, of which there is a much
greater mass. It actually degrades at a rate twice that of motion
picture film elements of the same format, the iron oxide in magnetic
sound film is considered to be an accelerator.

It would be interesting to see what the acidity level is of this
1953 tape. If you would be willing to sample it, I will send you two
different kinds of Acid-Detection strips. And I will share the
results on this listserve. That way we can start to quantify this
phenomenon of triacetate tape degradation.

Best regards,

Ed H. Zwaneveld
Technological Research and Development
National Film Board of Canada
March 1, 2001