Patent ID: 7601412

Claim:
An information recording medium comprising: a substrate including a first material on a surface thereof, a second material formed as recording marks on a first area of surface of the first material, and a third material formed as spaces on a second area of the surface of the first material and at least having a surface curvature or a surface energy which is different from a surface curvature or a surface energy of the second material, wherein the second material and the third material possess at least different chemical or physical characteristics, and at least the surface energy or the surface curvature of the third material is greater than the surface energy or the surface curvature of the second material, the third material is a metal material and a relation between an average thickness of a sum of the second material and the third material Dt and a minimum size of the recording marks Sm satisfies formula (1) and formula (2) or formula (3) and formula (4): Dt*10/ Z ≦Sm Formula (1) Z<4 Formula (2) Dt*10/4≦Sm Formula (3) Z>4 Formula (4) where Z is a ratio of the third material surface energy to the second material surface energy, and an area formed of the third material contains less than 20 percent of the second material allowing the second material or the third material to melt so that recording or read can be performed.