Re: [ARSCLIST] Rezerex presentation AES NYC 4/12(was Re: Baking tapes and hig...

[Mwcpc6@xxxxxxx]

In a message dated 4/13/2005 2:35:00 PM Eastern Standard Time,
lists@xxxxxxxxxxxxx writes:
For this we need more data.
I have actually seen sticky shed on non-backcoated tape, but it is rare.  If
it occurs on non-backcoated tape, the backcoat cannot be the only cause- but
why is it so rare on non-backcoated tape?  The answer could be that the
manufacturers changed the binder chemistry at around the same time they
started back coating the tape.  Another, possible, answer is that something
in the backcoat could be acting as a catalyst to increase binder breakdown
in the recording layer.
******************

I too am sure I have non-back coated tape with sticky shed, discovered after
spooling non-back coated tape from mixed reels so I could use the "good" tape.
 However this tape had been in close proximity to the back coating of the
other tape on the reel for an extended period of time.

Also I heard back in the 70s from a tape manufacturer (not Ampex or 3M) that
the binder for their back coating was the same as for the oxide layer.
Removing the back coating would remove a significant amount of the culprit binder.
Meanwhile the extensive handling of the tape by Richardson's method could have
the same effect as baking on the rest.

There are a lot of variables involved.

Mike Csontos