Patent ID: 8157929

Claim:
A magnetic shielding material for shielding geomagnetism, comprising, by mass, 70.0 to 85.0% of Ni, 1.0 to 6.0% of Cu, 2.0 to 10.0% of Mo and 0.2 to 2.0% of Mn, and the balance being essentially Fe, the magnetic shielding material having a relative magnetic permeability (μr) of 40,000 or more under a magnetic field of 0.05 A/m, a relative magnetic permeability of 112,500 or more under a magnetic field of 0.4 A/m, and a squareness ratio Br/B 0.8 of 0.80 or less, the squareness ratio being a ratio of a residual magnetic flux density (Br) to a maximum magnetic flux density (B 0.8 ) on a DC hysteresis curve under a maximum magnetic field of 0.8 A/m, and wherein the magnetic shielding material is produced by cold rolling where a total reduction of the cold rolling is not less than 60% and no annealing is performed between passes of the cold rolling.