Magnetic tape having servo pattern and characterized magnetic layer, and magnetic tape device

Patent metadata

Field	Value
Publication number	US-10891982-B2
Application number	US-202016848331-A
Country	US
Kind code	B2
Filing date	Apr 14, 2020
Priority date	Mar 23, 2018
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

The magnetic tape includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which a magnetic tape total thickness is equal to or smaller than 5.30 μm, the magnetic layer has a servo pattern, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, and an isoelectric point of a surface zeta potential of the magnetic layer is equal to or greater than 5.5.

First claim

What is claimed is:

1. A magnetic tape comprising:
a non-magnetic support; and
a magnetic layer including a ferromagnetic powder on the non-magnetic support,
wherein a thickness of the non-magnetic support is 3.00 to 4.50 μm,
the magnetic layer has a servo pattern,
a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, and
an isoelectric point of a surface zeta potential of the magnetic layer is equal to or greater than 5.5.

2. The magnetic tape according to claim 1 ,
wherein the isoelectric point is 5.5 to 7.0.

3. The magnetic tape according to claim 1 ,
wherein the magnetic layer includes a binding agent including an acidic group.

4. The magnetic tape according to claim 3 ,
wherein the acidic group includes at least one kind of acidic group selected from the group consisting of a sulfonic acid group and a salt thereof.

5. The magnetic tape according to claim 1 ,
wherein the center line average surface roughness Ra measured regarding the surface of the magnetic layer is 1.2 nm to 1.8 nm.

6. The magnetic tape according to claim 1 , further comprising:
a non-magnetic layer including a non-magnetic powder between the non-magnetic support and the magnetic layer.

7. The magnetic tape according to claim 1 , further comprising:
a back coating layer including a non-magnetic powder on a surface of the non-magnetic support opposite to a surface provided with the magnetic layer.

8. A magnetic tape device comprising:
the magnetic tape according to claim 1 ;
a magnetic head; and
a servo head.

Assignees

• Fujifilm Corp

Inventors

• Kasada Norihito

Classifications

• G11B5/70

  on a base layer · CPC title

• G11B5/706 Primary

  characterised by the composition of the magnetic material · CPC title

• G11B5/735

  characterised by the back layer {(magnetic recording media substrates G11B5/739)} · CPC title

• G11B5/702 Primary

  characterised by the bonding agent · CPC title

• G11B5/78

  Tape carriers · CPC title