Magnetic tape and magnetic recording device

摘要

An aspect of the present invention relates to a magnetic tape comprising a magnetic layer containing a hexagonal ferrite magnetic powder and a binder on a nonmagnetic support, wherein a standard deviation σHk of a magnetic anisotropy constant Hk of the magnetic layer is equal to or less than 30%, and a magnetic interaction ΔM as calculated by equation (1) below falls within a range of −0.20≦ΔM≦−0.03: ΔM=(Id(H)+2Ir(H)−Ir(∞))/Ir(∞) . . . (1) wherein Id(H) denotes a residual magnetization measured with DC demagnetization, Ir(H) denotes a residual magnetization measured with AC demagnetization, and Ir(∞) denotes a residual magnetization measured at an applied magnetic field of 796 kA/m.

主权项

1. A magnetic tape comprising a magnetic layer containing a hexagonal ferrite magnetic powder and a binder on a nonmagnetic support, wherein:
the hexagonal ferrite magnetic powder has an average plate ratio ranging from 2.5 to 5.0, a switching field distribution SFD ranging from 0.1 to 1.2, and an average plate diameter ranging from 10 to 50 nm, the standard deviation σHk of the magnetic anisotropy constant Hk of the magnetic layer is equal to or less than 30%, and the magnetic interaction ΔM as calculated by equation (1) below falls within a range of −0.20≦ΔM≦−0.03:
ΔM=(Id(H)+2Ir(H)−Ir(∞))/Ir(∞)  (1) wherein Id(H) denotes a residual magnetization measured with DC demagnetization, Ir(H) denotes a residual magnetization measured with AC demagnetization, and Ir(∞) denotes a residual magnetization measured at an applied magnetic field of 796 kA/m (10 kOe).