The comment was that old tapes absorb moisture into the oxide, which
makes things sticky and causes the oxide to stick to the wrong spots
and flake off the tape. The solution is to set the tape in a fruit
dryer at modest heat (150 F or so) for a while.
Presumably a desiccator, vacuum or otherwise, could serve too.
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This has been discussed here in the past.
Some tape formulations (for me, late 70's BASF, Memorex is the worst)
absorb mosture and the polymers in the binder decompose into lighter
molecules which migrate to the surface.
A temporary solution is to bake the tapes. 150 F sounds somewhat high
though.
There are dangers to doing this, though, depending on the condition
of the tape. You can dry out and glue adjacent layers of tape together
if you aren't careful.
There are also things you can do with custom tape transports to minimize
sticking when attempting to recover poorly preserved tape.