Patent ID: 7445852

Claim:
A magnetic substrate comprising a heat resistant resin and/or a precursor thereof applied on at least a part of a side or on at least a part of both sides of an amorphous metal ribbon represented by the general formula: (Co (1−c) Fe c ) 100−a−b X a Y b wherein X represents at least one species of element selected from the group consisting of Si, B, C and Ge, Y represents at least one species of element selected from the group consisting of Zr, Nb, Ti, Hf, Ta, W, Cr, Mo, V, Ni, P, Al, Pt, Rh, Ru, Sn, Sb, Cu, Mn and rare earth elements, c, a and b respectively satisfy 0≦c≦1.0, 10<a≦35 and 0≦b≦30, and a and b are represented in terms of atomic %; and the heat resistant resin comprises a resin that satisfies the following characteristics: (1) the weight loss rate owing to the thermal decomposition in a thermal history of 2 hr in a nitrogen atmosphere at 350° C. is 1% by weight or less; (2) the tensile strength after a thermal history of 2 hr in a nitrogen atmosphere at 350° C. is 30 MPa or more; (3) the glass transition temperature is from 120° C. to 250° C. (4) the temperature at which the melt viscosity is 1,000 Pa·s or less is not lower than 250° C. and not higher than 400° C.; and (5) the heat of fusion owning to crystals in the resin, which has been cooled from 400° C. to 120° C. at a rate of 0.5° C./min is 10 J/g or less.