PRODUCTION OF MAGNETIC DISK SUBSTRATE MADE OF TITANIUM

• Main Authors: SUENAGA HIROYOSHI, OMURA MASAKI, MORITA KENJI, OKANO YOKO, SAKIYAMA TOSHIO
• Format: Patent
• Language: English
• Published: 08.01.1993
• Subjects: APPARATUS THEREFOR; CHEMISTRY; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; METALLURGY; PHYSICS; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS

PURPOSE:To extremely improve a CSS characteristic and to impart magnetic anisotropy to a magnetic film by subjecting the entire surface of a titanium surface to concentrical texturing, then to an anodic oxidation treatment. CONSTITUTION:The titanium plate is subjected to the fine texturing along the circumferential direction over its entire surface. The groove depth of the texturing is specified to >=0.03mum and the number of the grooves per 1mm is specified to >=75 pieces and <=400 pieces. The surface of the titanium plate is subjected to an anodic oxidation treatment. The anodic oxidation treatment voltage is specified to 10 to 30V and the current density at the end of the oxidation to <=5X10<-4>A/mm . The anodized layer (titanium oxide layer) is formed on the surface of the front material in this way and while the effect of the texturing to impart the magnetical anisotropy is maintained, the sufficient surface hardness is imparted and the CSS characteristic is extremely improved even if the floating quantity is 0.075mum. The medium which can make high- density recording is thus obtd.