On Sat, 24 Mar 2012 15:36:06 +1100, Rod Speed wrote:

The Natural Philosopher wrote
dennis@home wrote
The Natural Philosopher wrote

And the lacquer is a spun coated thermosetting *plastic* resin.

ITYM its usually UV setting and its really not a plastic layer at all,
its just thick enough to level the disk for the printing.

Only you dennis would print on the data side of a DVD...sigh..

All the stamped CDs do.

For commercial discs, I think the data is engraved into the transparent
plastic disc; the reflective surface is then pressed onto this (and
carries no information on its own), then a lacquer layer goes down to
protect the reverse side of the reflective surface, then finally artwork
is printed on top of that. The laser shines through the transparent disc,
with the beam disrupted by the engraving.

There isn't really a "data side" as such because it ends up in the middle
of the sandwich:

Screen-printed artwork / text
Lacquer
Reflective surface
Engraved data (on top surface of transparent disc)
Transparent disc
[laser shines from this side]

I'm not sure how this process differs when it comes to home-writable
media, however; presumably there's a layer of magic between the
transparent disc and the reflective surface (and bugger knows how
rewritable works! :-)

cheers

Jules