The invention relates to the field of the protection of security documents such as for example banknotes and identity documents against counterfeit and illegal reproduction. In particular, the present invention provides processes for optical effect layers (OEL) exhibiting two or more nested indicia using a magnetic assembly comprising i) a soft magnetic plate (x31) comprising a) one or more voids (V) and b) one or more indentations (I) and/or one or more protrusions (P), and ii) one or more dipole magnets (x32).

The invention relates to the field of the protection of security documents such as for example banknotes and identity documents against counterfeit and illegal reproduction. In particular, the present invention provides processes for optical effect layers (OEL) exhibiting two or more nested indicia using a magnetic assembly comprising i) a soft magnetic plate (x31) comprising a) one or more voids (V) and b) one or more indentations (I) and/or one or more protrusions (P), and ii) one or more dipole magnets (x32).

There is provided a method for producing metal foils, capable of easily crystalizing amorphous soft magnetic material of a plurality of metal foils into nano-crystal soft magnetic material by uniformly heating the metal foils. A laminate obtained by laminating the metal foils made of amorphous soft magnetic material is held by a holding member such that adjacent metal foils can be separated from each other in a laminated direction of the laminate. By conveying either the holding member or magnets in a direction perpendicular to the laminated direction as a conveying direction such that the holding member and the magnets come close to each other, the adjacent metal foils are separated from each other with a magnetic force of the magnets. The separated metal foils are heated to crystalize the amorphous soft magnetic material of the metal foils into nano-crystal soft magnetic material. The same magnetic pole of the magnets aligns in the laminated direction.

There is provided a method for producing metal foils, capable of easily crystalizing amorphous soft magnetic material of a plurality of metal foils into nano-crystal soft magnetic material by uniformly heating the metal foils. A laminate obtained by laminating the metal foils made of amorphous soft magnetic material is held by a holding member such that adjacent metal foils can be separated from each other in a laminated direction of the laminate. By conveying either the holding member or magnets in a direction perpendicular to the laminated direction as a conveying direction such that the holding member and the magnets come close to each other, the adjacent metal foils are separated from each other with a magnetic force of the magnets. The separated metal foils are heated to crystalize the amorphous soft magnetic material of the metal foils into nano-crystal soft magnetic material. The same magnetic pole of the magnets aligns in the laminated direction.

A soft magnetic alloy or the like combining high saturated magnetic flux density, low coercive force and high magnetic permeability μ′ having the composition formula (Fe.sub.(1−(α+β))X1.sub.αX2.sub.β).sub.(1−(a+b+c+d+e))B.sub.aSi.sub.bC.sub.cCu.sub.dM.sub.e. X1 is one more elements selected from the group consisting of Co and Ni, X2 is one or more elements selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Bi, N, O and rare earth elements, and M is one or more elements selected from the group consisting of Nb, Hf, Zr, Ta, Ti, Mo, W and V. 0.140<a≤0.240, 0≤b≤0.030, 0<c<0.080, 0<d≤0.020, 0≤e≤0.030, α≥0, β≥0, and 0≤α+β≤0.50 are satisfied.

A soft magnetic alloy or the like combining high saturated magnetic flux density, low coercive force and high magnetic permeability μ′ having the composition formula (Fe.sub.(1−(α+β))X1.sub.αX2.sub.β).sub.(1−(a+b+c+d+e))B.sub.aSi.sub.bC.sub.cCu.sub.dM.sub.e. X1 is one more elements selected from the group consisting of Co and Ni, X2 is one or more elements selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Bi, N, O and rare earth elements, and M is one or more elements selected from the group consisting of Nb, Hf, Zr, Ta, Ti, Mo, W and V. 0.140<a≤0.240, 0≤b≤0.030, 0<c<0.080, 0<d≤0.020, 0≤e≤0.030, α≥0, β≥0, and 0≤α+β≤0.50 are satisfied.

To obtain a magnetic core having an improved withstand voltage property while maintaining a high relative magnetic permeability, and the like. The magnetic core contains large particles observed as soft magnetic particles having a Heywood diameter of 5 μm or more and 25 μm or less and small particles observed as soft magnetic particles having a Heywood diameter of 0.5 μm or more and less than 5 μm in a cross section. C1<C2 is satisfied in which an average circularity of the small particles close to the large particles is C1 and an average circularity of all small particles observed in the cross section including small particles not close to the large particles is C2. The small particles close to the large particles are defined as small particles whose distance from centroids of the small particles to a surface of the large particles is 3 μm or less.

To obtain a magnetic core having an improved withstand voltage property while maintaining a high relative magnetic permeability, and the like. The magnetic core contains large particles observed as soft magnetic particles having a Heywood diameter of 5 μm or more and 25 μm or less and small particles observed as soft magnetic particles having a Heywood diameter of 0.5 μm or more and less than 5 μm in a cross section. C1<C2 is satisfied in which an average circularity of the small particles close to the large particles is C1 and an average circularity of all small particles observed in the cross section including small particles not close to the large particles is C2. The small particles close to the large particles are defined as small particles whose distance from centroids of the small particles to a surface of the large particles is 3 μm or less.

A manufacturing method for an electronic component includes preparing a first composite magnetic section provided with a first composite magnetic layer and at least one marker layer disposed on the first composite magnetic layer; and preparing a second composite magnetic section provided with a second composite magnetic layer and at least one coil formed by winding a conductive wire and buried in the second composite magnetic layer with part of the coil being exposed. The manufacturing method further includes obtaining a multilayer body by disposing the first composite magnetic section so that a surface on the opposite side of the first composite magnetic section to a surface where the marker layer is disposed opposes a surface of the second composite magnetic section; and obtaining a molded body having a marker area formed with non-conductive particles pressed into the first composite magnetic layer.

A manufacturing method for an electronic component includes preparing a first composite magnetic section provided with a first composite magnetic layer and at least one marker layer disposed on the first composite magnetic layer; and preparing a second composite magnetic section provided with a second composite magnetic layer and at least one coil formed by winding a conductive wire and buried in the second composite magnetic layer with part of the coil being exposed. The manufacturing method further includes obtaining a multilayer body by disposing the first composite magnetic section so that a surface on the opposite side of the first composite magnetic section to a surface where the marker layer is disposed opposes a surface of the second composite magnetic section; and obtaining a molded body having a marker area formed with non-conductive particles pressed into the first composite magnetic layer.