| 摘要 |
PROBLEM TO BE SOLVED: To obtain, at low cost, an excellent optical recording medium similar to that obtained by using gold as a light-reflecting layer by forming a thin film of an Ag-Cu alloy of specific composition on a transparent substrate, heating it up to specific temp. in an oxidizing atmosphere, and allowing it to color into golden color. SOLUTION: A light-absorbing layer 20, containing organic pigment such as phthalocyanine type pigment, is formed on a transparent substrate 10 of polycarbonate, etc. Subsequently, a thin Ag-Cu alloy film is formed by a D.C. magnetron sputtering method by using, as a target, an Ag-Cu alloy having a composition which consists of 20-90 pts.wt. Ag and 10-80 pts.wt. Cu and in which the total amount of Ag and Cu is regulated to >=70 pts.wt. After heating treatment is applied to it up to 70-150 deg.C in an oxidizing atmosphere such as air to color it into golden color and form a light- reflecting layer 30 composed of a thin metallic film, a protective layer 40 of acrylic ultraviolet-setting resin, etc., is further formed on it in succession. By this method, the optical recording medium excellent in design characteristic and reliability, similar to that in the case were gold is used as a light-reflecting layer, can be obtained at a low cost. |
