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Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469
Dear David:
Regarding the EPA, Whale oil, etc.  In 1970 the EPA was created by  
Congress.  In 1972 the Marine Mammal Protection Act banned hunting of  
whales and this was supplemented in 1982 when the UN also passed an  
international whale hunting ban as whales were in danger of  
extinction.  Whale oil is a good mechanical lubricant and is used in  
oiling precision mechanisms such as watches and clocks, but it was  
never used as a binder lubricant in tape manufacture.  Chemical  
Engineering has synthesized whale oil so as to reduce the demand for  
natural whale oil.  There may be an after market lubricant based on  
either natural or synthetic whale oil which some use in attempting to  
"re-lubricate" a tape that has squealing problems.  It is a very  
limited band aide short term remedy which is not approved by chemists  
as safe.
In 1976 the Toxic Substances Act banned the use of Polychlorinated  
Biphenyl chemicals or PCB's.  PCBs were used as a liquid coolant in big
AC power transformers used by the electric utility companies.  PCBs  
were used in transformers, some motors, and some capacitors.  PCBs  
were never used in tape manufacture.  There was a major environmental  
disaster in the 1970s when companies dumped large quantities of PCBs  
into the Hudson River and the James River, creating a poisoned water  
environment that will take centuries to remedy.  Chlorine, and most of  
its compounds are dangerous poisons, thus they are banned unless one  
gets a waiver and/or an EPA license which can only be had by instituting
strict material use and disposal controls that met EPA chemical safety  
standards.
PVC, Polyvinyl Chloride, was used in Europe for some time by BASF and  
AGFA in the manufacture of their base films.  Ampex used a PVC binder,  
but only in their 600 series of tapes.  There is a major chemical  
problem with PVC.  Any loose radical Chlorine atoms can readily  
combine with moisture to form Hydrochloric Acid, or HCL.  When this  
happens, the HCL will attack the head core materials and the tape head  
gaps, which drastically shortens head life and causes major problems  
in the head gap area.  So for both environmental problems of handling  
Chlorine, and its bad habit of generating HCL and eating tape heads,  
PVC was dropped from tape manufacture, decades ago, with the exception  
of its continued use for decades in the Ampex 600 series tape binder  
chemistry.
The seeds of the disaster that have lead to Sticky Shed Syndrome arise  
in tape maker chemical changes of the 1970s, is an important and  
interesting story.  I do not believe that the government had anything  
to do with these tape chemical changes.  They were done by tape makers  
for various reasons unrelated to government regulation.
Hope this helps.
Charles Richardson
On Apr 5, 2008, at 6:25 PM, David Lennick wrote:
I will stand corrected if that's the case, but that was what I heard  
at the time.
dl
Tom Fine wrote:
Hi David:
Are you sure the whale oil story is true. I was told it is  
mythology and that the real story is that certain solvents couldn't  
be used in the manufacturing process anymore.
-- Tom Fine
----- Original Message ----- From: "David Lennick" <dlennick@xxxxxxxxxxxx 
>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Saturday, April 05, 2008 12:04 PM
Subject: Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469
"Environmental law changes forced most tape manufactures to change  
the
formula of their binder in the early 70's."
Read: They used to use whale oil, then they went to synthetic.