公开(公告)号：US20230081800A1

公开(公告)日：2023-03-16

申请号：US18054809

申请日：2022-11-11

Applicant: FUJIFILM Corporation

Inventor： Atsushi MOROOKA

IPC: G11B5/66 ,  G11B5/706 ,  G11B5/714

Abstract: The magnetic recording medium has an arithmetic average roughness Ra of a surface of a magnetic layer is 2.2 nm or less, a fluorine concentration A obtained by X-ray photoelectron spectroscopy performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees being 5 atom % or more and 50 atom % or less, and B, which is calculated by Equation 1 from an integrated intensity Ftotal of fragments derived from a fluorine-containing compound obtained for an entire region in a thickness direction of a cross section of the magnetic layer by line profile analysis of TOF-SIMS and an integrated intensity Fupper of fragments derived from a fluorine compound obtained for a region from the surface of the magnetic layer to an intermediate thickness in the thickness direction of the cross section, being 60% or more and 95% or less, Equation 1:B=(Fupper/Ftotal)×100.

公开(公告)号：US20180096700A1

公开(公告)日：2018-04-05

申请号：US15716622

申请日：2017-09-27

Applicant: FUJIFILM Corporation

Inventor： Atsushi MOROOKA ,  Toshio TADA

IPC: G11B5/008 ,  G11B5/706

CPC classification number: G11B5/00813 ,  G11B5/70 ,  G11B5/70678 ,  G11B5/78

Abstract: Provided is a magnetic tape in which a vertical direction squareness ratio and/or a longitudinal direction squareness ratio obtained by measurement performed by sweeping an external magnetic field in the magnetic tape in a predetermined range by a vibrating sample magnetometer is 0.70 to 1.00, and A calculated by Expression 1 is equal to or smaller than 5.0%. In Expression 1, n represents the number of measurement points measured at magnetic field strength of −40 kA/m to 40 kA/m during the sweeping and is 52, Mr(Hex) represents a magnetization quantity measured at magnetic field strength Hex, and μ represents an arithmetical mean of Mr(Hex) obtained by measurement performed in the range of the magnetic field strength during the sweeping. A = 100 × 1 n - 1  ∑ Hex = - 40  kA / m ∼ 40   kA / m   ( Mr  ( Hex ) - μ ) 2 / μ Expression   1