MAGNETIC TAPE AND MAGNETIC RECORDING AND REPRODUCING DEVICE
First Claim
1. 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 Δ
SFD in a longitudinal direction of the magnetic tape calculated by Expression 1 is equal to or smaller than 0.50,
Δ
SFD=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, andan 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 μ
m to 0.08 μ
m.
1 Assignment
0 Petitions
Accused Products
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.
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Citations
15 Claims
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1. 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 Δ
SFD in a longitudinal direction of the magnetic tape calculated by Expression 1 is equal to or smaller than 0.50,
Δ
SFD=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 μ
m to 0.08 μ
m. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. 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 Δ
SFD in a longitudinal direction of the magnetic tape calculated by Expression 1 is equal to or smaller than 0.50,
Δ
SFD=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 μ
m to 0.08 μ
m. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15)
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Specification