Corrosion Resistance of Next Generation Magnetic Disk (1)

― Corrosion Resistance Improvement Technology of Magnetic Disk by Pre-treatment ―

Abstract

The fabrication of the corrosion-resistant film on the disk by the pretreatment process using benzotriazole (BTA) solution was for the purpose of corrosion resistant improvement of patterned media. The most suitable pretreatment condition that corrosion resistance was improved is 30-minute dipping to a borate solution containing 1.0% BTA added 3% hydrogen peroxide 3%. By using this pretreatment, the corrosion resistance of the Co alloy in the neutral environment was improved more than 20 times. When hydrogen peroxide was not coexist, the degree of corrosion-resistant improvement was small. The corrosion resistance of the record and the layers which constitute a hard disk conducted pretreatment is maintained in 65℃ and 90% RH condition. A nitrogen group derived from BTA giving corrosion resistance is introduced into the disk surface which prepared pretreatment process. The reason that the BTA layer formation promotes by hydrogen peroxide addition was explained by in the HSAB principle.