US 12,243,571 B2
Magnetic recording medium having a core part level difference
Sogo Oikawa, Tokyo (JP)
Assigned to Sony Group Corporation, Tokyo (JP)
Appl. No. 18/284,215
Filed by Sony Group Corporation, Tokyo (JP)
PCT Filed Mar. 17, 2022, PCT No. PCT/JP2022/012167
§ 371(c)(1), (2) Date Sep. 26, 2023,
PCT Pub. No. WO2022/209935, PCT Pub. Date Oct. 6, 2022.
Claims priority of application No. 2021-061963 (JP), filed on Mar. 31, 2021.
Prior Publication US 2024/0371405 A1, Nov. 7, 2024
Int. Cl. G11B 5/78 (2006.01); G11B 5/008 (2006.01); G11B 5/706 (2006.01); G11B 23/107 (2006.01)
CPC G11B 5/78 (2013.01) [G11B 5/00813 (2013.01); G11B 5/70642 (2013.01); G11B 5/70678 (2013.01); G11B 23/107 (2013.01); G11B 2220/655 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A magnetic recording medium of a tape form, comprising:
a magnetic layer; and
an underlayer,
wherein a core part level difference Rk is 5.5 nm or less in a bearing curve generated on the basis of height data of a magnetic layer-side surface acquired using an atomic force microscope, and
wherein an average thickness of the underlayer is 1.50 μm or less.