Date: Sun, 14 Apr 2002 02:43:48 -0400
From: Ted White <tedwhite at compusnet.com>
To: WSFA members <WSFAlist at keithlynch.net>
Subject: [WSFA] Re: CDs, CD-Rs, and CD-RWs
Reply-To: WSFA members <WSFAlist at keithlynch.net>

ronkean at juno.com wrote:

> [...]
>
> I have heard a report that CDs have been attacked by fungus in tropical
> environments, with the fungus getting between the aluminum foil and the
> plastic disk.

Ah yes, "CD rot."  This "urban myth" has been around since at least 1985, and
is about as likely as the notion of applying green magic marker to the
*edges* of a CD "so it will track better."

In reality the "aluminum foil" exists to supply an opaque and reflective
background.  Conventional CDs are impressed with millions of pits which have
two basic depths, providing two different levels of reflectivity.  These pits
are impressed on the *label* side and then overlaid with a layer of aluminum,
over which the label is printed.   Thus the label side is the most vulnerable
to scratches and gouges -- which will take out data.   The "playing" side is
protected by the thickness of the plastic disc, and any scratches can be
buffed out.

--Ted White