Perpendicular Recording Media by Means of Anodic Oxidation

Details of method are given for measurements of perpendicular magnetic alumite discs obtained by anaid of anodization with the additional new process named "pore widening" which was effective tocontrol the coersive force. the electro-deposited fine iron needles in single crystallineThe perpendicular orientation of magnetization was confirmed. The magnetic recordingrigid discs indicated satisfactor results as perpendicular recording medium. Therecording characteristics of 3.k and 5.25 inch rigid discs were evaluated. A recording densityD <50> of 50 KBPI was attained for the disc with a media thickness 1.5 <micrn>m. the environmentaltest under an atomsphere of 40 - C90% r.h. over 1000hr affirmed the stability of the alumite disc with 250a SiO2 overcoat. theproposed perpendicular media by anodic oxidation method show a high potential for practical use因为它的mass productivity。

Details of method are given for measurements of perpendicular magnetic alumite discs obtained by an aid of anodization with the additional new process named "pore widening" which was effective to control the coersive force. The electro-deposited fine iron needles were in single crystalline state. The perpendicular orientation of magnetization was confirmed. The magnetic recording characteristics of rigid discs indicated satisfactor results as perpendicular recording medium. The recording characteristics of 3.k and 5.25 inch rigid discs were evaluated. A recording density D_<50> of 50 KBPI was attained for the disc with a media thickness 1.5 <micrn>m. The environmental test under an atomsphere of 40 ゜C, 90% R.H. over 1000 hr affirmed the stability of the alumite disc with 250A SiO2 overcoat. The proposed perpendicular media by anodic oxidation method show a high potential for practical use because of its mass productivity.