Patent ID: 9394204
Filing Date: 2016-07-19
CPC Classification: C04B,H01F,H01Q,Y10T

Claim Text:
1. A method of preparing molded ferrite sheet having opposing surfaces and a thickness in a range of 30 μm to 430 μm, comprising subjecting at least one surface to roughening said surface, wherein at least one surface of said opposing surfaces having the following surface roughness characteristics (a) to (c): (a) a center line average roughness is in the range of 170 nm to 800 nm, (b) a maximum height is in a range of 3 μm to 10 μm, and (c) an area occupancy rate of cross-sectional area taken along a horizontal plane at a depth of 50% of the maximum height in a square of side 100 μm is in a range of 10 to 80%, comprising preparing said molded ferrite sheet by applying a coating of a ferrite-dispersed coating liquid to a support and drying the applied coating, wherein the ferrite has been obtained by a mixture of 100 parts by weight of a ferrite powder having a cumulative 50% volume diameter of 0.1 to 1.0 μm and 5 to 40 parts by weight of a ferrite powder having a cumulative 50% volume diameter of 3 to 10 μm so that the surface roughness characteristics (a) to (c) are imparted to a surface of the dried coating in contact with said support.