Patent ID: 8440283

Claim:
An information recording medium comprising an information layer on a substrate, wherein said information layer has a metal layer, which is characterized in that: (1) said information layer has a concavo-convex portion formed on said substrate, (2) said metal layer essentially consists of Al, Si, and M (wherein M is at least one element selected from a group consisting of Cr and Ni), optical property of the metal layer can be changed by irradiating said metal layer with laser beam, to form an added mark, whereby reproducible information can be recorded by laser-beam irradiation, and an Al atom content is 20 atomic % or more and 94 atomic % or less and an Si atom content is 3 atomic % or more and 77 atomic % or less and an M atom content is 3 atomic % or more and 77 atomic % or less assuming that a total number of Al atoms, Si atoms and M atoms contained in said metal layer is 100 atomic %.