公开(公告)号：US20170117075A1

公开(公告)日：2017-04-27

申请号：US15312288

申请日：2015-05-21

Applicant: TODA KOGYO CORP.

Inventor： Yoji OKANO ,  Makoto SADAI ,  Shingo HONDA ,  Mitsunori KURUMADA ,  Akihiro YOSHIDA ,  Kazuyoshi KAWATO

IPC: H01F1/34 ,  C04B35/26 ,  H05K9/00

Abstract: The present invention relates to a ferrite sintered plate having a composition comprising 47 to 50 mol % of Fe2O3, 7 to 26 mol % of NiO, 13 to 36 mol % of ZnO, 7 to 12 mol % of CuO and 0 to 1.5 mol % of CoO, as calculated in terms of the respective oxides, in which the ferrite sintered plate has a volume resistivity of 1×108 to 1×1012·cm and a thickness of 10 to 60 μm; and a ferrite sintered sheet comprising the ferrite sintered plate on a surface of which a groove or grooves are formed, and an adhesive layer and/or a protective layer formed on the ferrite sintered plate, in which the ferrite sintered sheet has a magnetic permeability at 500 kHz a real part of which is 120 to 800 and an imaginary part of which is 0 to 30, and a product (μm) of the real part of the magnetic permeability at 500 kHz of the ferrite sintered sheet and a thickness of the ferrite sintered plate is 5000 to 48000. The ferrite sintered plate and the ferrite sintered sheet according to the present invention have a high volume resistivity as well as a large μ′ value and a small μ″ value of a magnetic permeability thereof, and therefore can be suitably used as a shielding plate in a digitizer system.