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Re: [ARSCLIST] Mould &tape
Hi Will; Sorry about your problems. In order to prevent this, one
needs to know the basics of chemistry/biology and take the right
steps to stop it. Generally, any organic material in the presence of
moisture is a candidate for mold and fungus problems. Mold and fungus
are primitive organic biological life forms which feed upon organic
materials in a weakened or near terminal state. Mold and fungus acts
as a scavenger or a 'funeral undertaker' in completing the organic
life cycle of living substances. In magnetic tape, all its
chemicals, with the exception of the inorganic magnetic particles and
perhaps some lubricants, can be attacked by mold and fungus. Thus the
base film, the binder chemicals, and the carbon black back coating
substances are open to this attack. Ordinary air usually has some
free mold and fungus spores in it. When these spores can land, find a
suitable home and growth situation, they will reproduce explosively,
doing the damage you mention. Being living predatory parasitic
organisms, they must have food for their life and reproduction cycle.
Thus they then eat away at tapes and other tasty organic materials.
Some mold and fungus has a powerful appetite and it "Pigs Out" rapidly
on its prey while other forms "take it slow." There are various
remedies, some safe and some not. One does need to take precautions
to stop the outbreak or spread of mold or fungus and also to prevent
personal injury and health problems. There are parties who know how
to do this safely.
As to attacking tape heads, etc, no, the mold and fungus does not
attack them directly because these items are inorganic materials.
However, mold and fungus have a physical structure similar to that of
a sponge and thus can carry and/or retain other chemicals that will
attack the heads. The additional moisture in the fungus can directly
oxidize the metal parts,. If the moisture combines with other tape
chemicals, then alcohol, carboxyl acid or hydrochloric acid can be
generated which will attack the heads. Cross contamination from the
tape, to the tape machine parts, and then to more tapes is certainly a
possibility. It does happen in some cases. However, a very thorough
effective cleaning can usually prevent this.
You are also correct that in general, the tape problems are getting
worse. The reasons are multiple and interactive. There are some
problems in the manufacture of tape, with the carbon black back
coating being one of the worst chemical mistakes of all time. It is a
moisture sponge and a seed bed for the growth of mold and fungus. In
my laboratory work and published chemical paper, there is direct
visual microscopic evidence why this is the case. Shown are high 800X
magnification pictures of the mold and fungus attacking the carbon
black. Tapes which do not have the carbon coating are generally much
more resistant to the deterioration problems. When the carbon black is
completely removed from both tape surfaces, the mold and fungus it
contains is removed and disposed of. The restored tape recovers
superbly to a nearly new condition. So far there has not been a
recurrence of mold and fungus attacks with properly restored tapes.
Do take note of the real fact that tapes have extraordinary positive
chemical capabilities. If handled right they will be cured of their
problems, come back to normal use, and be highly archival with superb
sonic performance. The tapes can last for the ages, provided they are
not subjected to ruinous abused by ill considered destructive
remedies. Human mistreatment of one kind or another is
the major source for causing and failing to permanently fix the tape
problems. Treat a tape respectfully with clear headed, complete,
correct, and comprehensive chemical understanding and it will return
the favor many times over.
It is remarkable that with 30 years of major tape problems, endless
complaints from customers, dispositive laboratory evidence, that
tapes continue to be made with the awful carbon black coating. This
repeated error just guarantees more future tape problems of the very
same kind will come to pass year after year. Many parties opine that
a tape is inherently inferior if it does not have carbon black coating
on it. Analytic Chemists know better. However, tape makers are
pressured by the market to add the carbon coating to the tapes, in
complete disregard of the chemical analysis not to do so.
Other problems arise from handling and storage issues. Many quick
fix remediation methods make matters much worse, not better, because
of the many inherent damaging magnetic and chemical consequences.
Even so, typical tape problems can be corrected if there is the
willingness and ability to do strict chemical science and use new
restoration methods with exacting precision. However, If the current
entrenched erroneous beliefs and practices continue unabated, the
future is grim and dim not only for tape but many other media, etc,
The increasing negative trend towards tape disaster is not forced upon
us by inexorable fate. It is largely brought on by human failure to do
and then follow the high level sophisticated chemical science the
matter requires for solution.
Best Wishes, Charlie Richardson
On Jul 21, 2008, at 9:31 AM, Prentice, Will wrote:
The following quote is taken from the website of an audio transfer
business in the southwest of Scotland (http://www.preciousvoices.co.uk/
)
"[Mould on tapes is] caused by storing tapes in damp or humid places
during warm moist Summers and its destroying tapes as never before.
Its
as infectious to other tapes as measles is to children and if it gets
onto the recording heads of tape players it destroys them too, as well
as infecting every other tape played on that machine. So its not
surprising that there isn't a professional audio restorer in the World
that will handle mouldy tapes. From a rare phenomena seven years ago
its
now affecting almost ten per cent of all the old audio and video tapes
seen by specialist audio restorers."
Does this reflect anyone else's experience?
Will
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