Magnetic and recording characteristics of a Co-Cr/Ni-Fe double-layered tape medium for perpendicular magnetic recording were investigated. The Co-Cr/Ni-Fe tape medium was prepared by the Facing Targets Sputtering (FTS) system on 10-μm-thick polyimide film. The requirements of the Co-Cr/Ni-Fe tape medium for use in a VTR system, such as softness and μ
i of the Ni-Fe layer, were examined. In order to improve the μ
i of a Co-Cr/Ni-Fe tape medium, which is decreased by magnetic interaction between the Ni-Fe layer and the Co-Cr recording layer, a 0.03-μm-thick Co
67Cr
33 interlayer with a small
Ms of 51 emu/cc was prepared. Recording and reproducing experiments using a helical-scan VTR machine were carried out on the Co-Cr/Ni-Fe tape medium. Reproduced output of 115 nV
o-p/(μm・T・m/s) at a low linear density and a CN ratio at 61 kFRPI of 51.4 dB (R. B. W. = 10 kHz) were obtained by using a TRF head with a 0.2-μm-thick main pole.
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