Patent ID: 6846583

Claim:
A magnetic recording medium comprising: a substrate; and a magnetic recording layer which is formed on the substrate and composed of an ordered alloy; wherein the ordered alloy has an L1 0 type crystalline structure containing at least one transition metal element of Co and Fe and at least one noble metal element of Pt and Pd, and further contains B, wherein an atomic ratio between the transition metal element and the noble metal element satisfies the following relationship: 0.45≦transition metal element)/(transition metal element+noble metal element)≦0.55, and wherein the magnetic recording layer is composed of magnetic crystal grains and a crystal grain boundary to surround the magnetic crystal grains, and a relationship of C 1 >C 2 is satisfied provided that C 1 represents a concentration of the transition metal element in the magnetic crystal grains and C 2 represents a concentration of the transition metal element in the crystal grain boundary.