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Hi John

Further to your re-plasticisation technique, a German and Austrian collaboration researched re-plasticisation  of acetate tape with the results presented at ILKAR.  These comments subsequently appeared in the Summer 2011 ARSC Newsletter 126 (http://www.arsc-audio.org/newsletter/nslr126.pdf)

"Nadja Wallaszkovits (Phonogrammarchiv, Austrian Academy of Sciences, Vienna) gave a paper that belied its title `Digitisation of Highly Degraded Acetate Tapes - A Treatment Report ́. Fortunately, there was nothing about digitisation! The paper gave a detailed discussion of one extreme example of plasticiser loss in acetate tapes, described how plasticiser loss and vinegar syndrome were two independent phenomena, and showed the result of a novel re-plastification process for all acetate materials that
is being patented. No details were given, but the patent application will be published soon. Replastification was contemplated also for old films, but (in my view) probably the thickness will require very long processing times." 

Has anything come of this research?

Best wishes
Nigel


-----Original Message-----
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of John Schroth
Sent: Monday, 2 March 2015 10:34 a.m.
To: [log in to unmask]
Subject: Re: [ARSCLIST] Distressing data point for upcoming ARSC tape playback workshop

Hi Tom:


Kodak has known about VS for many many years. Early tins from the 1940's and possibly earlier have a small relief in the inside film lid that is disk shaped. Inside the relief was 3-4" diameter disk of thin paperboard with a metal mesh grill covering it to hold the paperboard in place but allow the chemical put on the paperboard to slowly dissipate into the film can. The chemical was a solution mostly containing camphor. It is well-documented that camphor helps to slow the beginnings of VS. I have used camphor to slowly re plasticize very dry and brittle motion picture acetate base film that had VS. Quite possibly the same could be done for audiotape in the same condition? I got this recipe from someone at LOC. 
You place a small amount of natural camphor, 2-3 pieces about half the size of a sugar cube each, in the bottom of a metal film tin. (camphor and be easily found at Indian grocery stores - they use camphor for special ceremonies) With some small wood blocks (or portions of a pencil
- no paint on the pencil and no eraser because the camphor will eat paint and eraser) you suspend the film on the reel above the camphor. 
Close the lid and seal it. The camphor is dissolved into the film. It takes many many many months (my latest project has been almost two
years) but the film which was once so brittle, it would easily break when bent, is now more pliable and depending on how much shrinkage has occurred. Sometimes you can work with the film enough to scan it. Again it would be interesting to test this with audiotape in the same condition.

My quick fix recipe for cupped and curling acetate audiotape is to increase the tension settings on my ATR reel to reel deck and add several additional guideposts on each side to keep the tape from curling over itself on it's way to and from the head block. It isn't pretty but it has worked for the few times I needed to make a transfer where the tape is curling so much, it would not make it from the reel to the first tape guide without curling over on itself.

Regards,

John Schroth