Longevity of DVD-R and CD-R (Was MagTapes)

[Philip Pemberton]

In message <6.1.2.0.2.20050314145210.0227d3f8 at popmail.ucsd.edu>
          "Eric F." <elf at ucsd.edu> wrote:

> Curious though ... why do the edges get attacked first?  Are the disks 
> slapped together in some sort of fashion such that there exists a potential
> breach at the edges?

Think about it - there's a 1" plastic hub in the center, followed by a ridge,
then the data layer. On the outside of the disc there is no plastic hub/ridge
to protect it - maybe 1/16" of "unused" dye, then the data itself.

Also, a lot of the Taiwanese media manufacturers (read: CMC and crew) skimp
on the amount of adhesive and enamel coat they use to seal the discs. That
basically means you end up with a disc that will at best fail early, or at
worst delaminate completely. I had a CMC-made "unbranded" blank that
delaminated in a 24x CD-ROM drive, taking the drive on a one-way trip to
silicon heaven. Truly awful discs.

Later.
-- 
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