Title:
MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING/PLAYBACK DEVICE AND MAGNETIC RECORDING MEDIUM CARTRIDGE
Document Type and Number:
Japanese Patent JP2021034107
Kind Code:
A
Abstract:
To provide a magnetic recording medium capable of exerting a favorable travelling performance when in use.SOLUTION: This magnetic recording medium is a tape-shaped magnetic recording medium and comprises a substrate, an underlayer provided on the substrate, and a magnetic layer provided on the underlayer. Recesses with a depth of 20% or more of the average thickness of the magnetic layer are formed in the surface of the magnetic layer at the ratio of 20 or more and 200 or less per 1600 μm2. A logarithmic decrement in the surface of the magnetic layer, obtained by a pendulum viscoelasticity test at a temperature of 10°C or higher and 45°C or lower is 0.025 or more and 0.040 or less. Difference between a maximum value of the logarithmic decrement and a minimum value of the logarithmic decrement is 0 or more and 0.020 or less. The squareness ratio in the vertical direction is 65% or more. Average thickness of the magnetic layer is 80 nm or less. The average thickness of the magnetic recording medium is 5.6 μm or less.SELECTED DRAWING: Figure 1
Inventors:
YAMAGA MINORU
Application Number:
JP2019227536A
Publication Date:
March 01, 2021
Filing Date:
December 17, 2019
Export Citation:
Assignee:
SONY CORP
International Classes:
G11B5/70; G11B5/706; G11B5/71; G11B5/73; G11B5/738; G11B5/78; G11B15/43
Domestic Patent References:
| JP2017228333A | 2017-12-28 | |||
| JP2017228328A | 2017-12-28 | |||
| JP2009087468A | 2009-04-23 | |||
| JP2004273070A | 2004-09-30 | |||
| JP2019003712A | 2019-01-10 | |||
| JP2006065953A | 2006-03-09 | |||
| JP2007273036A | 2007-10-18 | |||
| JP2006099919A | 2006-04-13 | |||
| JP2004005891A | 2004-01-08 |
Attorney, Agent or Firm:
Patent Business Corporation Tsubasa International Patent Office