LARGE-CAPACITY-MEMORY DISK

摘要

LARGE-CAPACITY-MEMORY DISK In a large capacity memory disk of the type in which data are read out by an optical system, the invention provides a large capacity memory disk characterized in that a methyl methacrylate copolymer consisting of 99 to 20 percent by weight methyl methacrylate and 1 to 80 percent by weight of a monomer copolymerizable with methyl methacrylate is used as the disk substrate.