Howell said:A new type of Blu-Ray digital video disk made largely from paper has been developed by Sony and Toppan Printing in Japan. The two companies say such paper-based disks will be cheaper to make and less environmentally harmful.
...
The resulting prototype consists of 51 per cent paper but is still capable of storing up to 25 gigabytes of data. Regular DVDs have less than half this capacity.
Link Source