Recording characteristics of electroless-plated conirep films with an in-plane anisotropic initial layer

Two kinds of electroless-plated CoNiReP media were fabricated using the underlayers of electroless-plated NiP and NiMoP films. Namely, the perpendicular anisotropic CoNiReP film with an in-plane anisotropic initial layer (Hc(//)=50 Oe) plated onto the almost nonmagnetic electroless NiMoP underlayer and the perpendicular anisotropic CoNiReP film plated onto the nonmagnetic NiP underlayer. These media were evaluated as flexible disks combined with a Sendust ring head. A high reproduced voltage was obtained in the CoNiReP/NiMoP double layer media compared to that in the CoNiReP/NiP double layer media. Also, recording up to a very high density of 300 kFRPI was achieved. Thus, the medium with a quasi-soft magnetic in-plane anisotropic initial layer is suggested to be preferred to the higher density recording media combined with a ring head.