An optical recording medium having a scratch-off material layer includes a transparent substrate, a reflective layer formed on the transparent substrate, a protective layer formed on the reflective layer, information formed on a surface of the protective layer, and at least one opaque scratch-off material...http://www.google.fr/patents/US6901043?utm_source=gb-gplus-shareBrevet US6901043 - Scratch-off material layer applied on optical recording media
Scratch-off material layer applied on optical recording media
