Re: [ARSCLIST] Cleaning moldy video tape

["Richard L. Hess" <arclists@xxxxxxxxxxxxxxx>]

At 07:12 PM 7/10/2006, steven c wrote:
> Am I reading
> your post correctly in thinking that the "binder matrix" (which,
> I assume, is the magnetic coating applied to the plastic tape)

The binder matrix is a variety of polyester polyurethanes or 
polyether polyurethanes that contain the gamma Fe2O3 or CrO2 
particles and also has lubricant mixed in with it. The ester-type 
lubricants are widely used and they are not unrelated to vegetable 
and animal oils. Perhaps it is the lubricant that initially attracts 
the fungus plus the ability of the binder matrix to act as a sponge 
not only for the lubricant but for water as well.


> Then, again...that conjures of visions of mouldy 45's or LP's...not
> to mention mouldy Corvettes...(t-i-c, BTW)

While I think mold (I think the Cdn Oxford prefers this spelling) can 
grow on 45's and LP's, I'm not sure the same type of spongy matrix 
exists in the pressed vinyl as compared to the polymerized matrix of 
the binder/oxide coating on the tape. Remember, the binder is 
polymerizing on demand, so to speak, as it is being applied to the base film.

I've been having some fun chemistry lessons <smile/sigh>.

Cheers,

Richard


Richard L. Hess                   email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada       (905) 713 6733     1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.