| 摘要 |
PURPOSE:To lower the friction resistance between a head slider and an optical disk surface at the time when the optical disk begins to rotate by forming the ruggedness of the prescribed center line average height measured by a prescribed method on the surface. CONSTITUTION:The optical disk 1 is formed by successively laminating a transparent substrate 2, a recording layer 3 formed thereon and a layer 4 contg. spherical particles. The ruggedness having 0.01 to 2mum, more preferably 0.03 to 1.0mum center line average height measured by a method described in JIS B0601 is formed on the surface of the layer 4. This layer 4 is formed of a coated film forming material contg. 0.1 to 20wt.% spherical particles with which, for example, the average particle diameter D is expressed by L/2mum<D<=(L +4)mum (where L is the film thickness of the layer) and in which >=75% of the spherical particles are the spherical particles of D(1+ or -0.2)mum. Inorg. spherical particles consisting of silica, alumina, etc., or spherical particles consisting of synthetic resins, such as polyester resin and polystyrene resins, are usable for the spherical particles. |
