Plastics expert witness Dr. George Pasternack has this to say on coatings for web form plastic films:
The rapid cure speed of UV curable coatings has enabled manufacturers of CDs and DVDs to maximize manufacturing line speed (~ 3 to 4 seconds per unit). Two different types of UV materials are used in the manufacture of CDs. First, a UV abrasion resistant clear coat is spin coated onto the metal reflective layer. The protected metallized surface is then screen printed with a UV curable ink. In the case of DVDs, a UV curable adhesive is used to bind the protective polycarbonate layer to the metallized polycarbonate layer. The viscosity of the CD clear coat varies between 10 to 100 cps at 25o C, and the viscosity of DVD adhesives is less than 1,000 cps at 25o C.
For more see http://mysite.verizon.net/mb.pasternack/