RESIN DISK SUBSTRATE FOR INFORMATION CARRIER

摘要

PROBLEM TO BE SOLVED: To provide an information carrier resin disk substrate, in which the surface of the resin is modified to avoid the damages such as a crack and a plastic deformation, and to provide its manufacturing method, a disk shaped information carrier and a resin surface hardening method. SOLUTION: A hardened layer 2a is formed by supplying carbon ions to the surface of a disk substrate 2 made of amorphous polyolefin and a magnetic layer 3 and a protective layer 4 are provided on the layer 2a to form a magnetic disk 1. Thus, the substrate 2 receives no damage even though a head 5 contacts with the disk 1 during recording and reproducing due to a minute gap d between the disk 1 and the head 5.