Just curious...why would you put a piece of that packing tape (ulta-sticky) on your CD?
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Compact Discs are normally 12 cm in diameter and 1.2 mm thick. Pits are formed in the polycarbonate disk layer by an injection molding process. This is then referred to as the data layer. A thin layer (50-100 nm) of metal (aluminum - most cases, gold or silver) covers the pits to act as the reflective layer. Following metal deposition, a thin plastic layer (10-30 microns) is spin-coated on over the metal. This can be a nitrocellulose layer suitable for air-drying, or an acrylic plastic that is cured in UV and acts as the protective layer. Finally, a label or logo may be silk-screened on the top. Notice that the pits are far closer to the protective/silk-screened side of the disk (~ 20 microns) than they are to the read-side of the disk (~1.1 mm). Thus, it is easier to permanently damage a disk by scratching the top -- than the bottom! That is why a scratch on the label side can be [email protected] near fatal to the life of that cd.
I agree with the above posters about getting the cd replaced.
Good luck and be careful with that packing tape.
There is a laquering/varnishing process that coats the metalized layer with about 30 microns of plastic to protect the information surface. And, not all CDs have a label e.g. 100th Window by Massive Attack. The foil layer is made by evaporation deposition (not really sprayed) onto the surface that was pressed with the information so as to make it reflective. The fact that this protective layer came off so easily with the label means a manufacturing defect.
At the very least Cdc deserves a replcement.