Eisboch wrote:
"JimH" wrote in message
oups.com...



Same here. I have never had a CD that I burnt fail yet, although I do
have to clean them once in a while after being handled a lot.

What theoretically is supposed to happen to the data burnt onto CD's
over time?



I don't know. The original music CD was simply a polycarbonate disk coated
with aluminum (done in a vacuum process called "sputtering" and then
protected with an overcoat of lacquer done in a spin process.

A CD-R differs in the respect that there is an additional layer of some type
of organic dye that reacts to the laser when writing data. I suspect that
it is the stability of the dye that has been exposed to the beam that
determines storage life.

I looked around the 'net and there are all kinds of opinions on storage life
ranging from a few years to over 100 years. Heat and humidity appears to be
the determining factors, other than physical abuse or damage.

Eisboch




I've had a number of them deteriorate in 5-7 years, many of them were
really cheap blanks I used to backup my audio CD's and left in my car,
so in addition to being cheap they endured temperature extremes. They
weren't visually damaged but skipped more and more until they wouldn't
play. I've had other CD-Rs more than 10 years old still fine.