DVD Demystified

Disc and Data Details
Figure 5.3
Dual-layer
construction
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on each substrate, separated by a very thin, transparent adhesive film. The
second method, developed by 3M (now Imation), puts one layer on a substrate
and then adds a second layer to the same substrate using a photopolymer
(2P) material.
A dual-layer disc can be made in two different ways (Figure 5.3):
1. One layer on each side
a. Stamp the outer data layer into the first substrate.
b. Add a semireflective coating.
c. Stamp the inner layer “upside down” on the second substrate.
d. Add fully reflective coating.
e. Flip the second substrate over and glue with transparent adhesive
to the first.