RE: Question About Effects of Heat/Sunlight on CDs/CDRs

["Moorman, Jon" <jonmoorman@xxxxxxxxxxxxx>]

I live in Georgia (US) and haven't had any problems with keeping CDs or
CDRs in my car for extended periods.  You do, and this may seem obvious,
you do need to keep them out of direct sunlight.  I've had friends that
have melted CD cases and my wife has even warped a cassette box, so
direct sun no matter where (geographically) you are is bad.

CDs (silvers) and CD-Rs are quite different physically and I believe
that CDRs are more susceptible to heat.  CDs actually have peaks and
valleys that are read by the CD reader.  Think a mouthful of teeth with
a couple missing.  The gaps do not reflect light back to the CD reader.
CDRs emulate this by using dye.  Instead of peaks and valleys, there are
dark and light areas.  The dark areas imitate the "gaps" by absorbing
the light of the CD reader.  "Burning" your CDR heats up the dye into
the required pattern.  CDR dye is meant to be "burned" once.  This is in
contrast to CDRW dye which is designed for multiple burns and is likely
more susceptible to heat.

All that said, I think it would be unlikely that CDRs would lose their
data/music by heat until the surface physically (perhaps not visibly)
warped.  However, exposure to sunlight could (possibly) cause the dye to
fade quicker than it ought to.  When you get down to this level of
looking at the physical CDR, you can also see where having a long term
dye (TY, Fuji, etc.) as opposed to a short term dye, is preferable.

The short of this: don't leave your CDs or CDRs in the sun and never put
them in the oven! :)  Your choice of CDR is also critical.

Hope this helps,
-jon