A very valid point, but my concerns about DVDs extend past the layer 
corrosion. I (and others, I believe) are most concerned about the 
stability and thoroughness of the bonding between the two halves.

I am concerned about:
(1) Long-term stability of the bond and its aging characteristics
(2) Mechanical stresses on the bond as induced by storage cases, disc 
printers, and other devices
(3) Thermal and humidity cycling effects on the bond

This is, of course, in addition to the normal concerns about dye and 
reflective layer stability.



At 11:42 AM 4/26/2006, Jerome Hartke wrote:
>Good points as applicable to CD discs where the metal layer may be protected
>by only a few micrometer thick protective layer. I am not sure that the gold
>vs. silver issue is as significant for DVD where the information layer,
>including metal, is sandwiched between two 0.6 mm thick half discs that
>isolate it from harmful chemicals. Of course, the bonding layer must extend
>fully to the rim.
>Media Sciences, Inc.

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