Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus

Patent metadata

Field	Value
Publication number	US-2020251139-A1
Application number	US-202016777201-A
Country	US
Kind code	A1
Filing date	Jan 30, 2020
Priority date	Jan 31, 2019
Publication date	Aug 6, 2020
Grant date	—

Abstract

The magnetic tape include a non-magnetic support and a magnetic layer including ferromagnetic powder and a binding agent, in which the magnetic layer has a timing-based servo pattern, an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference (L 99.9 −L 0.1 ) between a value L 99.9 of a cumulative distribution function of 99.9% and a value L 0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and an isoelectric point of a surface zeta potential of the magnetic layer is 5.5 or more.

First claim

What is claimed is:

1 . A magnetic tape comprising:
a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent, wherein the magnetic layer has a timing-based servo pattern, wherein an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference L 99.9 −L 0.1 between a value L 99.9 of a cumulative distribution function of 99.9% and a value L 0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and wherein an isoelectric point of a surface zeta potential of the magnetic layer is 5.5 or more.

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

3 . The magnetic tape according to claim 1 ,
wherein the binding agent is a binding agent containing an acidic group.

4 . The magnetic tape according to claim 3 ,
wherein the acidic group includes at least one type 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 timing-based servo pattern is a linear servo pattern which continuously extends from one side of the magnetic tape in a width direction to the other side thereof and is inclined at an angle α with respect to the width direction, and wherein the ideal shape is a linear shape extending in a direction of the angle α.

6 . The magnetic tape according to claim 1 ,
wherein the difference L 99.9 −L 0.1 is 100 nm or more and 180 nm or less.

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

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

9 . A magnetic tape cartridge comprising:
the magnetic tape according to claim 1 .

10 . The magnetic tape cartridge according to claim 9 ,
wherein the isoelectric point is 5.5 or more and 7.0 or less.

11 . The magnetic tape cartridge according to claim 9 ,
wherein the binding agent is a binding agent containing an acidic group.

12 . The magnetic tape cartridge according to claim 11 ,
wherein the acidic group includes at least one type of acidic group selected from the group consisting of a sulfonic acid group and a salt thereof.

13 . The magnetic tape cartridge according to claim 9 ,
wherein the timing-based servo pattern is a linear servo pattern which continuously extends from one side of the magnetic tape in a width direction to the other side thereof and is inclined at an angle α with respect to the width direction, and wherein the ideal shape is a linear shape extending in a direction of the angle α.

14 . The magnetic tape cartridge according to claim 9 ,
wherein the difference L 99.9 −L 0.1 is 100 nm or more and 180 nm or less.

15 . A magnetic tape apparatus comprising:
a magnetic tape; a reading element unit; and an extraction unit, wherein the magnetic tape is the magnetic tape according to claim 1 , wherein the reading element unit includes a plurality of reading elements each of which reads data from a specific track region including a reading target track in a track region included in the magnetic tape, and wherein the extraction unit performs a waveform equalization process with respect to each reading result for each reading element, to extract, from the reading result, data derived from the reading target track.

16 . The magnetic tape apparatus according to claim 15 ,
wherein the isoelectric point is 5.5 or more and 7.0 or less.

17 . The magnetic tape apparatus according to claim 15 ,
wherein the binding agent is a binding agent containing an acidic group.

18 . The magnetic tape apparatus according to claim 17 ,
wherein the acidic group includes at least one type of acidic group selected from the group consisting of a sulfonic acid group and a salt thereof.

19 . The magnetic tape apparatus according to claim 15 ,
wherein the timing-based servo pattern is a linear servo pattern which continuously extends from one side of the magnetic tape in a width direction to the other side thereof and is inclined at an angle α with respect to the width direction, and wherein the ideal shape is a linear shape extending in a direction of the angle α.

20 . The magnetic tape apparatus according to claim 15 ,
wherein the difference L 99.9 −L 0.1 is 100 nm or more and 180 nm or less.

Assignees

• Fujifilm Corp

Inventors

• Kasada Norihito
• Ozawa Eiki
• Musha Atsushi

Classifications

• G11B5/584

  for track following on tapes · CPC title

• G11B5/733

  characterised by the addition of non-magnetic particles {(base layers having a non-magnetic layer under a soft magnetic layer G11B5/736; magnetic recording media substrates G11B5/739)} · CPC title

• G11B5/702 Primary

  characterised by the bonding agent · CPC title

• G11B5/70678

  Ferrites · CPC title

• G11B5/735

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