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<DIV><FONT size=3>Walter,</FONT></DIV>
<DIV><FONT size=3>I worked with a sizable collection of two-inch that straddled the non-backcoated (3M's 849 and 399) and backcoated (400) tape stocks. The white crystalline deposits were common on the backcoated stocks and non-existent on the non-backcoated stuff. I suspect it was part of a program to create stocks that were more supple and less prone to flaking off the base.</FONT></DIV>
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<DIV><FONT size=3>Unless you've heard from a materials chemist, I'm leary of unilaterally declaring it "plasticizer". I tend to think of it more generically as a binder hydrolysis by-product. This fits with the similar experience on the audio side of the appearance of new back-coated tape stocks being linked to sticky-shed.</FONT></DIV>
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<DIV><FONT size=3>Steve Greene<BR>Audiovisual Archivist<BR>Nixon Presidential Library and Museum<BR>(301) 837-1772</FONT><BR><BR>>>> walterforsberg@gmail.com 3/17/2010 11:15:02 AM >>><BR></DIV>
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<DIV>Hello Quad Groupers-</DIV>
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<DIV>I'm looking for info / documentation / personal experiences any of you may have had with white plasticizer, offering itself up from the winds/packs of 2" and 1" videotape. </DIV>
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<DIV>Specifically, are there any trends or commonly believed reasons for this stuff appearing? (Eg. specific stocks, a particular environmental storage condition, or manufacturer's container / reel materials.)</DIV>
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<DIV>I'd also be happy to receive a quoted forward of past discussions on this topic, as I'm a relative newbie to the list. </DIV>
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<DIV>Happiest shamrocks & thanks in advance,</DIV>
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<DIV>Walter Forsberg</DIV>
<DIV>NYU-MIAP</DIV>
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