G PHYSICS
G11 INFORMATION STORAGE
G11B INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
G11B5/00 Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
G11B5/62 Record carriers characterised by the selection of the material
G11B5/68 comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
G11B5/712 characterised by the surface treatment or coating of magnetic particles