Magnetic recording medium

Abstract

Abstract PURPOSE:To improve running stability and the wear resistance of a back coat layer by providing the back coat layer contg. zirconia powder on the rear of a substrate having a magnetic layer on the front surface. CONSTITUTION:The zirconia powder is incorporated into the back coat layer. The zirconia powder to be used is an extremely hard polishing agent having 8 Mohs hardness and has preferably the average particle size within a 0.05-1.0mum range. The zirconia powder is used in a 0.3-70wt% range by the total weight of the binder component in the back coat layer. The back coat layer is usually formed by mixing and dispersing the zirconia powder together with the binder component, org. solvent and other additives, etc. to prepare the coating compd. for the back coat layer, coating such compd. on the rear surface of the substrate of a polyester film, etc. on the front surface of which the magnetic layer is preliminarily formed and drying the coating. The decrease of the SN ratio is thereby lessened and the magnetic recording medium having the excellent durability and running stability is obtd.

Inventors

• 👤 Akira Morioka
• 👤 章 森岡
• 👤 Takeshi Matsuura
• 👤 松浦　武志
• 👤 Yoshiyuki Takahira
• 👤 高平　義之

Bibliographic Details