On a replica substrate 1a, a reflection layer 11, a first dielectric layer 12 made of ZnS-SiO₂, a recording layer 13 made of a phase change type recording material, and a second dielectric layer 14 made of ZnS-SiO₂ are successively formed. In addition, a reaction protection layer 15 made of Si₃N₄ or SiO₂ is formed on the second dielectric layer 14. As a result, an information signal portion 1c is composed. A light transmissivity sheet is formed through an adhesive layer so that the light transmissivity sheet coats an information signal portion 1c. As a result, a light transmission layer is composed. When the reaction protection layer 15 is not formed, a reaction protection resin layer made of an ultraviolet ray setting resin is formed so that the reaction protection resin layer coats the information signal portion 1c.