Invention Grant
- Patent Title: Magnetic tape having characterized magnetic layer
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Application No.: US15900230Application Date: 2018-02-20
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Publication No.: US10431250B2Publication Date: 2019-10-01
- Inventor: Toshio Tada , Norihito Kasada
- Applicant: FUJIFILM Corporation
- Applicant Address: JP Tokyo
- Assignee: FUJIFILM Corporation
- Current Assignee: FUJIFILM Corporation
- Current Assignee Address: JP Tokyo
- Agency: Sughrue Mion, PLLC
- Priority: JP2017-029510 20170220
- Main IPC: G11B5/71
- IPC: G11B5/71 ; G11B5/712 ; G11B5/706 ; G11B5/008 ; G11B5/70

Abstract:
A magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support. The center line average surface roughness Ra measured regarding the surface of the magnetic layer is less than or equal to 1.8 nm. The logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is less than or equal to 0.050, and ΔSFD in a longitudinal direction of the magnetic tape calculated by Expression 1: ΔSFD=SFD25° C.−SFD−190° C. is greater than or equal to 0.35. In Expression 1, the SFD25° C. is the switching field distribution SFD measured in a longitudinal direction of the magnetic tape at a temperature of 25° C., and the SFD−190° C. is the switching field distribution SFD measured in a longitudinal direction of the magnetic tape at a temperature of −190° C.
Public/Granted literature
- US20180240493A1 MAGNETIC TAPE Public/Granted day:2018-08-23
Information query
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