A single-sided ablative write-once optical disk is usable without a protective cartridge. The disk includes the conventional radiation-transparent polycarbonate substrate that has one surface serving as the disk outer face and an opposite surface that supports the fluorinated hydrocarbon subbing layer...http://www.google.com.au/patents/US5510164?utm_source=gb-gplus-sharePatent US5510164 - Single-sided ablative worm optical disk with multilayer protective coating
