Humidity and Magnetic Media Was: Re: floppy media failure - test-drb@ccmp.vtda.org

10 Apr 2007

Hey All,

On 10/04/07, Philip Pemberton <classiccmp at philpem.me.uk> wrote:
...
  Al Kossow wrote:
  The failure mode I've seen is oxide/binder
coming off, clogging the head
 and
 carving little concentric rings in the media :-( 
 If it's a case of the binder absorbing moisture and losing grip, it might be
 an idea to try baking the discs for a bit to dry out the binder. The only
 problem is, if you get the disc too hot (the words 'Curie temperature' spring
 to mind) then the data's toast... 
I am in the process of reading a couple of papers[1] on the effects of
humidity on magnetic recording tape - primarily tape that has a
ployester urethane binder. Turns out that the problem is the binder
undergoing hydrolysis. The process is reversable but seems to take a
while - several weeks at least in low humidity conditions.

[...]

[1]
Kinetics of the humid aging of magnetic recording tape
Bertram, H.; Cuddihy, E.
Magnetics, IEEE Transactions on
Volume 18,  Issue 5,  Date: Sep 1982,  Pages:  993 - 999

Aging of magnetic recording tape
Cuddihy, E.
Magnetics, IEEE Transactions on
Volume 16,  Issue 4,  Date: Jul 1980,  Pages:  558 - 568

Simon

-- 
------------------------------------------------------------------------
"Well, an engineer is not concerned with the truth; that is left to
philosophers and theologians: the prime concern of an engineer is
the utility of the final product."
Lectures on the Electrical Properties of Materials, L.Solymar, D.Walsh