Magnetic tape having characterized magnetic layer and magnetic recording and reproducing device
AssigneeFUJIFILM Corporation
InventorsNorihito Kasada, Eiki Ozawa
Life of this patent
Estimating the term…
Abstract
Provided are a magnetic tape, in which a magnetic layer includes a ferromagnetic powder, a binding agent, and an oxide abrasive, ΔSFD in a longitudinal direction of the magnetic tape calculated by Expression 1, ΔSFD=SFD25° C.−SFD−190° C., is equal to or smaller than 0.50, a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050, and an average particle diameter of the oxide abrasive obtained from a secondary ion image obtained by irradiating the surface of the magnetic layer with a focused ion beam is 0.04 μm to 0.08 μm, and a magnetic recording and reproducing device including this magnetic tape.
Claims15
A magnetic tape comprising:
- a non-magnetic support;
- and
- a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support,
- wherein ΔSFD in a longitudinal direction of the magnetic tape calculated by Expression 1 is equal to or smaller than 0.50,
- ΔSFD=SFD25° C.−SFD−190° C. Expression 1,
- in Expression 1, the SFD25° C. is a switching field distribution SFD measured in the longitudinal direction of the magnetic tape at a temperature of 25° C., and the SFD−190° C. is a switching field distribution SFD measured in the longitudinal direction of the magnetic tape at a temperature of −190° C.,
- the magnetic layer includes an oxide abrasive,
- a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050, and
- an average particle diameter of the oxide abrasive obtained from a secondary ion image obtained by irradiating the surface of the magnetic layer with a focused ion beam is 0.04 μm to 0.08 μm.
A magnetic recording and reproducing device comprising:
- a magnetic tape;
- and
- a magnetic head,
- wherein the magnetic tape is a magnetic tape comprising:
- a non-magnetic support;
- and
- a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support,
- wherein ΔSFD in a longitudinal direction of the magnetic tape calculated by Expression 1 is equal to or smaller than 0.50,
- ΔSFD=SFD25° C.−SFD−190° C. Expression 1,
- in Expression 1, the SFD25° C. is a switching field distribution SFD measured in the longitudinal direction of the magnetic tape at a temperature of 25° C., and the SFD−190° C. is a switching field distribution SFD measured in the longitudinal direction of the magnetic tape at a temperature of −190° C.,
- the magnetic layer includes an oxide abrasive,
- a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050, and
- an average particle diameter of the oxide abrasive obtained from a secondary ion image obtained by irradiating the surface of the magnetic layer with a focused ion beam is 0.04 μm to 0.08 μm.
Dependencies are inferred from the claim text.