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Hi John:

If that's true about Kodak, really interesting because iron sourced to an Irish plant may be 
chemically different (at least as far as impurities and additives) from iron sourced to Audio 
Devices plants, which I think were in NJ or maybe NY. 3M made most or all US-sold tape in Minnesota, 
I think, with iron mines plentiful locally.

With 8mm film, are you sure there's no iron in the film emulsion, no iron in the film dyes, no iron 
whatsoever? What about other rusty metals?

I forgot to mention one other thing. I've handled quite a few Irish acetate tape reels over the 
years. I think all or most of the acetate stuff was original Orradio, pre-Ampex ownership. This 
would have been made in Alabama, again probably using a different source of iron from other US tape 
manufacturers. In my experience, Irish tapes rarely go vinegar. I can only think of one  case, and 
it was a reel I recovered from a very damp environment. Other Irish tapes from the same place 
haven't gone vinegar, but their boxes weren't warped and damp, so I suspect this tape had been 
wetter longer than the other tapes.

Finally, one more Scotch 111 datapoint. I have two Capitol mass-duped 2-track tapes. Both are likely 
on Scotch 111 because they are on Scotch-branded reels and the tape is light brown like 111. They 
both are circa 1956-57. The Steinberg-Pittsburgh reel was owned by my parents and always stored at 
ambient room northeastern US conditions. No vinegar, no warpage and surprisingly little 
print-through. The other tape, Stokowski, probably spent most of its life in the mid-Atlantic 
region, probably at ambient room conditions, until I got it a few years ago. It's as shrunk/warped 
and vinegar as a Kodak tape. Both tape boxes are equally clean, indicating to me that the vinegar 
tape was never directly exposed to water or a box-warping dampness. Go figure!

I'm thinking that there's more to acetate and vinegar syndrome than we know and thus hard/fast rules 
don't apply.

-- Tom Fine

----- Original Message ----- 
From: "John Schroth" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, March 01, 2015 7:14 PM
Subject: Re: [ARSCLIST] Distressing data point for upcoming ARSC tape playback workshop


> There might be something to iron/cellulose reaction.
>
> Keep in mind though, vinegar syndrome can start without iron/cellulose contacting each other (at 
> least in motion picture film). Prime example: I received on two separate occasions and from two 
> separate individuals Super 8mm motion picture films from Hawaii. No mag stripe. All short 50' 
> lengths on plastic reels, shot in the 1970's. This is quite young for film. Both collections were 
> stored in a basements of a house that were not air conditioned and pulled out from time to time to 
> run in a projector. Otherwise the films were all stored in ziplock bags, and then by one of the 
> owners also in Tupperware totes. The films would be exposed to the humid air then placed back in 
> airtight containers. They had some of the worst examples of vinegar syndrome I have ever seen. 
> Once job I turned down there was no way to rescue the film. The other took a ton of patience (and 
> vapors so strong it made your heads spin). So it is not an iron oxide contact with acetate that 
> alone begins VS, though it may speed up or begin the process earlier. The main reason for VS is 
> hydrolysis reacting to acetate.
>
> FWIW I just got off the phone with one of my buddies who was a film emulsion engineer at Kodak. To 
> the best of his recollection he believes Kodak made their own acetate based audiotape and the main 
> manufacturing plant was out of Ireland.
>
> Regards,
>
> John Schroth
>
> On 3/1/2015 6:21 PM, Tom Fine wrote:
>> Here's an idea that may need research -- what if what I'm calling "drying out" of acetate-backed 
>> tape IS vinegar syndrome, just with no vinegar smell? What if different iron oxide formulations 
>> cause the mechanism to happen in different ways to different degrees, but it's all related to 
>> iron/cellulose reactions?
>>
>> -- Tom Fine
>>
>> ----- Original Message ----- From: "John Schroth" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Sunday, March 01, 2015 5:55 PM
>> Subject: Re: [ARSCLIST] Distressing data point for upcoming ARSC tape playback workshop
>>
>>
>>> Hello Nigel:
>>>
>>> Interestingly enough, at an AMIA conference several years prior, there was an outfit - I cannot 
>>> remember where they were from, who claimed to have a new chemical process that could not only 
>>> halt vinegar syndrome but could reverse its effects on motion picture film. Everyone seemed very 
>>> excited about the announcement, but the group would not release any more information. They have 
>>> been quiet since.
>>>
>>> Regards,
>>>
>>> John Schroth
>>>
>>> On 3/1/2015 5:14 PM, Nigel Champion wrote:
>>>> 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
>>>
>>>
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