TW202036614A - Method for manufacturing inductor - Google Patents

Abstract

This method for manufacturing an inductor 1 comprises: a first step in which a wire 2 is positioned on one surface of a substrate in the thickness direction, the wire 2 having a cross section with a substantially circular shape and comprising a conductor 6 and an insulating layer 7 that covers the conductor 6; a second step in which a first magnetic sheet 51, containing first magnetic particles and a first binder 91 in which the first magnetic particles are dispersed, is positioned on one surface of a first release sheet 41 in the thickness direction so as to cover a major arc of the circumferential surface of the wire 2; and a fourth step in which a second magnetic sheet 52, containing second magnetic particles and a second binder 92 in which the second magnetic particles are dispersed, is used to cover one surface, in the thickness direction, of the first magnetic sheet 51 that covers the major arc of the circumferential surface of the wire 2 and the one surface of the first release sheet 41.

Description

Manufacturing method of inductor

The present invention relates to a method of manufacturing an inductor.

Previously, it has been known that inductors are mounted on electronic devices and the like and used as passive components such as voltage conversion components.

For example, an inductor is proposed that includes a rectangular parallelepiped chip main body made of a magnetic material and internal conductors such as copper embedded in the chip main body (see Patent Document 1).

In Patent Document 1, a plurality of layers of conductors containing conductive paste are laminated by printing to manufacture an inductor. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 10-144526

[The problem to be solved by the invention]

However, in recent years, higher inductance is required for inductors.

The present invention provides a manufacturing method capable of manufacturing an inductor with excellent inductance. [Technical means to solve the problem]

The present invention (1) includes a method for manufacturing an inductor, which includes: a first step of arranging wiring on a surface of a substrate in the thickness direction; the wiring includes a wire and an insulating layer covering the wire, and has a cross-sectional view Circular shape; the second step is to arrange the first magnetic sheet on a surface of the substrate in the thickness direction so as to cover an area exceeding 180° in the circumferential surface of the wiring, the first magnetic sheet Containing first magnetic particles, and a first binder for dispersing the first magnetic particles; and a fourth step of covering a surface of the first magnetic sheet in the thickness direction with a second magnetic sheet. 2 The magnetic sheet contains second magnetic particles including second anisotropic magnetic particles aligned in the plane direction, and a second binder for dispersing the second magnetic particles, and the first magnetic sheet covers the circumference The aforementioned area of the surface and the aforementioned one surface of the aforementioned substrate.

In this method, in the second step, the first magnetic sheet is arranged on one surface of the substrate in the thickness direction so that the first magnetic sheet is covered by the circumferential surface of the wiring in an area exceeding 180° when viewed in cross section, so that the first magnetic sheet can be densely arranged 1 Magnetic particles. As a result, an inductor with excellent inductance can be manufactured.

Furthermore, in the fourth step, the second magnetic sheet covers one surface of the first magnetic sheet in the thickness direction, so that the first magnetic particles and the second magnetic particles in the peripheral area of the wiring can be densely arranged. Therefore, an inductor with better inductance can be manufactured.

Therefore, according to this manufacturing method, the arrangement of the first magnetic particles and the second magnetic particles in the peripheral region can be dense, and an inductor with excellent inductance can be manufactured.

The present invention (2) includes the method for manufacturing an inductor as described in (1), wherein the first magnetic particles include first anisotropic magnetic particles, and the first anisotropic magnetic particles are contained in the first magnetic sheet Align in the surface direction.

According to this method, in the second step, the first magnetic sheet is arranged on one surface in the thickness direction of the substrate. In the first magnetic sheet, the first anisotropic magnetic particles are aligned along the thickness direction of the substrate. Therefore, it is possible to prevent the first anisotropic magnetic particles from aligning along the circumferential direction of the wire at the circumferential end edges of the above-mentioned area of the wire facing a surface in the thickness direction. Therefore, the DC superimposing characteristic of the inductor is excellent.

In addition, since the first magnetic sheet covers the area where the peripheral surface of the wiring exceeds 180°, at both ends of the area in the circumferential direction, the alignment direction of the first anisotropic magnetic particles can be changed from the circumferential direction of the wiring The first anisotropic magnetic particles are densely arranged along the direction of one surface of the substrate. As a result, an inductor with more excellent inductance can be manufactured.

Therefore, according to this method, an inductor with excellent inductance and DC superimposition characteristics can be manufactured.

The present invention (3) includes the method for manufacturing an inductor as described in (1) or (2), wherein the substrate is a release sheet, and the method for manufacturing the inductor further includes: a third step of removing the substrate And the fifth step, which is to cover the circumferential surface exposed from the other surface of the first magnetic sheet in the thickness direction of the third magnetic sheet, arranged in the thickness direction of the first magnetic sheet On the surface, the third magnetic sheet includes third magnetic particles and a third binder for dispersing the third magnetic particles.

In this method, since the third magnetic sheet is further arranged on the other surface of the first magnetic sheet in the thickness direction, the first magnetic particles and the second anisotropic magnetic particles in the peripheral area of the wiring can be densely arranged And the third magnetic particle. Therefore, an inductor with better inductance can be manufactured.

In particular, since the third magnetic sheet is covered on the circumferential surface exposed from the other surface in the thickness direction of the first magnetic sheet, it can be densely located in the area corresponding to the circumferential surface of the wiring exposed from the first magnetic sheet The third magnetic particles are arranged. As a result, an inductor with excellent inductance can be manufactured.

The present invention (4) includes the method for manufacturing an inductor as described in (3), wherein the third magnetic particles include third anisotropic magnetic particles, and the third anisotropic magnetic particles are contained in the third magnetic sheet Align in the surface direction.

According to this method, in the fifth step, the third anisotropic magnetic particles can be aligned in a region corresponding to the circumferential surface of the wiring exposed from the first magnetic sheet, and the third anisotropic magnetic particles can be densely arranged . As a result, an inductor with more excellent inductance can be manufactured.

The present invention (5) includes the method of manufacturing an inductor as described in (3) or (4), which implements the above-mentioned first step, the above-mentioned second step, and the above-mentioned third step in sequence, and then simultaneously performs the above-mentioned fourth step. Steps and Step 5 above.

In this method, since the fourth step and the fifth step are performed at the same time, the manufacturing time can be shortened compared with the method of sequentially performing the fourth step and the fifth step. Therefore, the inductor can be manufactured efficiently.

The present invention (6) includes the method for manufacturing an inductor as described in any one of (3) to (5), wherein the first adhesive in the second step and the third adhesive in the fifth step The agent contains a B-stage thermosetting component, and the inductor manufacturing method further includes a sixth step, which further makes the B-stage thermosetting components of the first adhesive and the third adhesive simultaneously C-stage化.

In this method, in the sixth step, the B-stage thermosetting components of the first adhesive and the third adhesive are simultaneously C-staged. Therefore, it is combined with the B-stage heat treatment of the first adhesive and the third adhesive. Compared with the method where the curable components are sequentially C-staged, the manufacturing time can be shortened. Therefore, the inductor can be manufactured efficiently.

The present invention (7) includes the method for manufacturing an inductor as described in (1) or (2), wherein the substrate is a third magnetic sheet, which includes third magnetic particles, and is used to combine the third magnetic particles The dispersed third adhesive, the third adhesive contains a cured product of a thermosetting component.

In this method, since the substrate is the third magnetic sheet, there is no need to perform the step of removing the substrate such as the release film. Therefore, the number of steps can be reduced, and the inductor can be easily manufactured.

The present invention (8) includes the method for manufacturing an inductor as described in (7), wherein the third magnet particles include third anisotropic magnet particles, and the third anisotropic magnet particles are contained in the third magnet sheet Align in the surface direction.

In this method, since the third magnetic particles include the third anisotropic magnetic particles oriented in the surface direction in the third magnetic sheet, the third anisotropic magnetic particles can face the third magnetic sheet along the wiring. Partial alignment. Therefore, an inductor with better inductance can be manufactured. [Effects of Invention]

The inductor manufacturing method of the present invention can manufacture an inductor with excellent inductance.

<The first embodiment> 1. Inductance The inductor obtained according to the first embodiment of the present invention will be described with reference to FIGS. 1A to 2B.

Furthermore, FIG. 1A shows the cross section after being shaded, and FIG. 1B is a cross-sectional view showing the alignment of the anisotropic magnetic particles in the magnetic layer. Furthermore, in the drawing of this project including FIG. 1B, in order to facilitate the understanding of the present invention, the shape and arrangement of the magnetic particles (including anisotropic magnetic particles) are exaggeratedly drawn.

As shown in FIGS. 1A to 1B, the inductor 1 has a shape extending in the plane direction. Specifically, the inductor 1 has one surface and the other surface facing in the thickness direction, and each of the one surface and the other surface has a direction included along the surface direction, and the wiring 2 (described below) transmits A flat shape in the direction of the current (corresponding to the depth direction of the paper) and the first direction orthogonal to the thickness direction.

The inductor 1 includes wiring 2 and a magnetic layer 3.

The wiring 2 has a substantially circular shape in cross-section. Specifically, the wiring 2 has a substantially circular shape when it is cut at a cross section (first direction cross section) orthogonal to the second direction (transmission direction) (the depth direction of the paper) that is the direction in which current is transmitted.

The wiring 2 is an electric wire covered with an insulating layer. Specifically, it includes a wire 6 and an insulating layer 7 covering the wire 6.

The wire 6 is a conductive wire having a shape extending long in the second direction. In addition, the lead wire 6 has a substantially circular cross-sectional shape that shares a central axis with the wiring 2.

Examples of the material of the lead wire 6 include metal conductors such as copper, silver, gold, aluminum, nickel, and alloys thereof, and preferably copper. The wire 6 may have a single-layer structure or a multiple-layer structure in which the surface of the core conductor (for example, copper) is plated (for example, nickel).

The radius R1 of the wire 6 is, for example, 25 μm or more, preferably 50 μm or more, and for example, 2000 μm or less, preferably 200 μm or less.

The insulating layer 7 protects the wire 6 from corrosion by chemicals or water, and prevents short circuit between the wire 6 and the magnetic layer 3. The insulating layer 7 covers the entire outer peripheral surface (circumferential surface) of the wire 6.

The insulating layer 7 has a substantially circular ring shape in cross-section that shares a central axis (center C) with the wiring 2.

As the material of the insulating layer 7, for example, polyvinyl formal, polyester, polyester imide, polyamide (including nylon), polyimide, polyimide imide, and polyurethane formic acid can be cited. Insulating resin such as ester. These materials may be used individually by 1 type, and may use 2 or more types together.

The insulating layer 7 may be composed of a single layer, or may be composed of multiple layers.

The thickness R2 of the insulating layer 7 is approximately uniform in the radial direction of the wiring 2 at any position in the circumferential direction, for example, 1 μm or more, preferably 3 μm or more, and for example, 100 μm or less, preferably 50 μm or less.

The ratio (R1/R2) of the radius R1 of the wire 6 to the thickness R2 of the insulating layer 7 is, for example, 1 or more, preferably 10 or more, for example, 500 or less, preferably 100 or less.

The radius R of the wiring 2 (= the radius R1 of the wire 6 + the thickness R2 of the insulating layer 7) is, for example, 25 μm or more, preferably 50 μm or more, and for example, 2000 μm or less, preferably 200 μm or less.

The magnetic layer 3 increases the inductance of the inductor 1. The magnetic layer 3 covers the entire outer peripheral surface (circumferential surface) of the wiring 2. The magnetic layer 3 forms the outer shape of the inductor 1. Specifically, the magnetic layer 3 has a rectangular shape extending in the plane direction (the first direction and the second direction). More specifically, the magnetic layer 3 has one surface and the other surface facing each other in the thickness direction, and each of the one surface and the other surface of the magnetic layer 3 forms one surface and the other surface of the inductor 1 respectively.

The magnetic layer 3 contains anisotropic magnetic particles 8 and a binder 9. Specifically, the material of the magnetic layer 3 is a magnetic composition containing anisotropic magnetic particles 8 and a binder 9. Preferably, the magnetic layer 3 is a cured product of a thermosetting resin composition (a composition containing anisotropic magnetic particles 8 and the following thermosetting components).

Examples of the magnetic material constituting the anisotropic magnetic particles 8 include soft magnets and hard magnets. From the viewpoint of inductance, it is preferable to use soft magnetic materials.

As the soft magnetic material, for example, a single metal body containing one metal element in a pure state, and for example, one or more metal elements (first metal element) and one or more metal elements (second metal element) and/or The eutectic (mixture) of non-metallic elements (carbon, nitrogen, silicon, phosphorus, etc.) is the alloy body. These can be used alone or in combination.

As the single metal body, for example, a metal element composed of only one type of metal element (first metal element) can be cited. As the first metal element, for example, iron (Fe), cobalt (Co), nickel (Ni), and other metal elements contained as the first metal element of the soft magnetic material are appropriately selected.

In addition, as a single metal body, for example, a form including a core containing only one metal element and a surface layer containing an inorganic substance and/or organic substance that modifies a part or all of the surface of the core, such as a form containing a first metal element The form of an organic metal compound or an inorganic metal compound after decomposition (for example, thermal decomposition). As the latter form, more specifically, iron powder (sometimes referred to as carbonyl iron powder) obtained by thermal decomposition of an organic iron compound (specifically, carbonyl iron) containing iron as the first metal element, and the like. Furthermore, the position of the layer containing the inorganic substance and/or the organic substance that modifies the part containing only one metal element is not limited to the surface as described above. Furthermore, the organometallic compound or inorganic metal compound that can obtain a single metal body is not particularly limited, and it can be appropriately selected from known or commonly used organometallic compounds or inorganic metal compounds that can obtain a single metal body for soft magnets.

Alloy system The eutectic of more than one metal element (first metal element) and more than one metal element (second metal element) and/or non-metal elements (carbon, nitrogen, silicon, phosphorus, etc.), as long as it is There are no particular restrictions on what can be used as an alloy body for soft magnetic materials.

The essential elements in the first metal element-based alloy body include, for example, iron (Fe), cobalt (Co), nickel (Ni), and the like. Furthermore, if the first metal element is Fe, the alloy system is set to Fe-based alloy; if the first metal element is Co, the alloy system is set to Co-based alloy; if the first metal element is Ni, the alloy system is set to Ni-based alloy.

The second metal element is an element (secondary component) contained in the alloy body and is compatible (eutectic) with the first metal element. For example, iron (Fe) (the first metal is other than Fe) (When the first metal element is an element other than Co), cobalt (Co) (when the first metal element is an element other than Co), nickel (Ni) (when the first metal element is an element other than Ni), chromium (Cr), aluminum (Al), silicon (Si), copper (Cu), silver (Ag), manganese (Mn), calcium (Ca), barium (Ba), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), molybdenum (Mo), tungsten (W), ruthenium (Ru), rhodium (Rh), zinc (Zn), gallium (Ga), indium (In), germanium (Ge), tin (Sn), lead (Pb), scandium (Sc), yttrium (Y), strontium (Sr) and various rare earth elements. These can be used individually or in combination of 2 or more types.

The non-metallic element is an element (secondary component) contained in the alloy body and is compatible (eutectic) with the first metal element. For example, boron (B), carbon (C), nitrogen (N), silicon (Si), phosphorus (P), sulfur (S), etc. These can be used individually or in combination of 2 or more types.

Fe-based alloys as an example of the alloy body include magnetic stainless steel (Fe-Cr-Al-Si alloy) (including electromagnetic stainless steel), iron-silicon aluminum alloy (Fe-Si-Al alloy) (including super iron-silicon aluminum alloy) ), Permalloy (Fe-Ni alloy), Fe-Ni-Mo alloy, Fe-Ni-Mo-Cu alloy, Fe-Ni-Co alloy, Fe-Cr alloy, Fe-Cr-Al alloy, Fe-Ni -Cr alloy, Fe-Ni-Cr-Si alloy, silicon copper (Fe-Cu-Si alloy), Fe-Si alloy, Fe-Si-B (-Cu-Nb) alloy, Fe-B-Si-Cr alloy , Fe-Si-Cr-Ni alloy, Fe-Si-Cr alloy, Fe-Si-Al-Ni-Cr alloy, Fe-Ni-Si-Co alloy, Fe-N alloy, Fe-C alloy, Fe-B Alloys, Fe-P alloys, ferrites (including stainless steel ferrites, Mn-Mg ferrites, Mn-Zn ferrites, Ni-Zn ferrites, Ni-Zn-Cu ferrites Ferrite, Cu-Zn ferrite, Cu-Mg-Zn ferrite and other soft ferrites, iron-cobalt alloy (Fe-Co alloy), Fe-Co-V alloy, Fe-based amorphous alloy, etc.

Examples of Co-based alloys of alloy bodies include Co-Ta-Zr and cobalt (Co)-based amorphous alloys.

As an example of an alloy body, Ni-based alloys include, for example, Ni-Cr alloys.

Among these soft magnets, from the standpoint of self-magnetic properties, alloy bodies are preferably cited, Fe-based alloys are more preferably cited, and iron-silicon aluminum alloys (Fe-Si-Al alloys) are more preferably cited. In addition, as the soft magnetic material, a single metal body is preferably used, a single metal body containing an iron element in a pure state is more preferably used, and an iron element or iron powder (carbonyl iron powder) is more preferably used.

As the shape of the anisotropic magnetic particles 8, from the viewpoint of anisotropy, for example, a flat shape (plate shape), needle shape, etc. can be cited. From the viewpoint of good relative permeability in the plane direction (two-dimensional), Preferably, it is flat.

The flatness (flatness) of the flat anisotropic magnetic particles 8 is, for example, 8 or more, preferably 15 or more, and for example, 500 or less, preferably 450 or less. The oblateness is calculated, for example, as the aspect ratio obtained by dividing the average particle diameter (average length) (described below) of the anisotropic magnetic particles 8 by the average thickness of the anisotropic magnetic particles 8.

The average particle diameter (average length) of the anisotropic magnetic particles 8 is, for example, 3.5 μm or more, preferably 10 μm or more, and for example, 200 μm or less, preferably 150 μm or less. If the anisotropic magnetic particles 8 are flat, the average thickness thereof is, for example, 0.1 μm or more, preferably 0.2 μm or more, and for example, 3.0 μm or less, preferably 2.5 μm or less.

The binder 9 disperses the anisotropic magnetic particles 8 in the magnetic layer 3. In addition, the adhesive 9 is dispersed in the magnetic layer 3 in a specific direction. Preferably, the adhesive 9 contains a cured product of a B-stage thermosetting component. In addition, the adhesive 9 will be described in detail in the description of the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53 in the following manufacturing method.

In the magnetic layer 3, the anisotropic magnetic particles 8 are aligned in the binder 9 and are uniformly arranged.

The magnetic layer 3 has a peripheral region 4 and an outer region 5 when viewed in cross-section (when the cross section is cut in the first direction).

The peripheral area 4 is the peripheral area of the wiring 2 and is located around the wiring 2 in contact with the entire outer peripheral surface (circumferential surface) of the wiring 2. The peripheral area 4 has a substantially circular ring shape in cross-section that shares a central axis with the wiring 2. More specifically, the peripheral region 4 is a region in the magnetic layer 3 that is located within a range from the center C of the wiring 2 to 1.5 times the radius R of the wiring 2. That is, the peripheral area 4 is an area located in a range from the outer periphery of the wiring 2 (the inner periphery of the peripheral area 4) to the radially outer side by a distance of 0.5 times the radius R of the wiring 2.

The peripheral area 4 includes a first area 11 and a second area 12.

Two first regions 11 are arranged in the peripheral region 4 at a distance from each other in the circumferential direction. Specifically, the first region 11 includes a third region 13 and a fourth region 14 arranged on the other side in the thickness direction at an interval from the third region 13.

The third region 13 covers at least the outer circumferential arc surface of the wiring 2 including one end edge E1 in the thickness direction, for example, at least the first semicircular arc including the one end edge E1 in the thickness direction of the cover wiring 2 (on one side of the thickness direction of the wiring 2) Part or all of a semicircular arc) surface 23 of the two ends E2 and E3 of the wiring 2 in the first direction. Preferably, the third region 13 covers a portion of the first semicircular arc surface 23 of the wiring 2, more specifically, when projected in the radial direction, it is included in a semicircular arc surface of the wiring 2. On the other hand, it does not It overlaps with the first direction end edges E2 and E3 of the wiring 2, and is arranged inside the first direction end edges E2 and E3.

Furthermore, one end edge E1 of the thickness direction of the wiring 2 is a first imaginary line L1 passing through the center C of the wiring 2 in the thickness direction and intersects the arc surface (first semicircular arc surface 23) of the wiring 2 in the thickness direction. The part.

In addition, both end edges E2 and E3 of the wiring 2 in the first direction are two portions where the third imaginary line L3 passing through the center C of the wiring 2 and the circumferential surface of the wiring 2 intersect along the first direction.

The fourth area 14 is arranged to face the third area 13 with the center C of the wiring 2 interposed therebetween. The fourth region 14 covers at least the outer circumferential arc surface of the wiring 2 including the other end edge E4 in the thickness direction, for example, the second semicircular arc of the covered wiring 2 including the other end edge E4 in the thickness direction (on the other side of the wiring 2 in the thickness direction) , A part of the other semi-circular arc) surface 24 connecting the two end edges E2 and E3 in the first direction. Specifically, when projected in the radial direction, the fourth region 14 is included in the second semicircular arc surface 24 of the wiring 2. On the other hand, it does not overlap with the both ends E2 and E3 of the wiring 2 in the first direction, and is arranged in The inner side of both ends E2 and E3 of the wiring 2 in the first direction.

The other end edge E4 of the thickness direction of the wiring 2 is a portion where the first imaginary line L1 passing through the center C of the wiring 2 and the second arc surface 24 intersect in the thickness direction.

The angle α1 of the central angle C1 of the third area 13 and the angle α2 of the central angle C2 of the fourth area 14 are appropriately set according to the application and purpose. The total angle (α1+α2) of the third area 13 is less than 360°, for example, preferably 270° or less, and for example, more than 180°, preferably 200° or more.

Specifically, the angle α1 of the central angle C1 of the third region 13 is, for example, 90° or more, preferably more than 90°, more preferably 120° or more, and for example, less than 180°, preferably 165° or less. Moreover, the angle α1 is preferably an obtuse angle.

The angle α2 of the central angle C2 of the fourth region 14 is, for example, 15° or more, and for example, 60° or less, preferably 45° or less. Moreover, the angle α2 is preferably an acute angle.

The angle α1 of the central angle C1 of the third area 13 is larger than the angle α2 of the central angle C2 of the fourth area 14, and the equal ratio (angle α1/angle α2) exceeds 1, preferably 1.5 or more, and is 3 or less, preferably 2 or less.

In the first region 11, the anisotropic magnetic particles 8 are aligned along the circumferential direction of the wiring 2.

In each of the third region 13 and the fourth region 14, the relative magnetic permeability of the anisotropic magnetic particles 8 is higher in the direction (for example, if the anisotropic magnetic particles 8 are flat, it is anisotropic magnetic The surface direction of the particles 8 is approximately the same as the circumferential direction. Specifically, the case where the angle between the surface direction of the anisotropic magnetic particle 8 and the tangent to the radially inner circumferential surface of the anisotropic magnetic particle 8 is 15° or less is defined as anisotropic magnetism The particles 8 are aligned in the circumferential direction.

The ratio of the number of anisotropic magnetic particles 8 aligned in the circumferential direction to the total number of anisotropic magnetic particles 8 contained in the first region 11 is, for example, more than 50%, preferably more than 70%, more preferably more than 80% . That is, the first region 11 may include, for example, less than 50%, preferably 30% or less, and more preferably 20% or less of anisotropic magnetic particles 8 that are not aligned in the circumferential direction.

The ratio of the area of the first area 11 (total area of the third area 13 and the fourth area 14) relative to the entire peripheral area 4 is, for example, 40% or more, preferably 50% or more, more preferably 60% or more, and for example It is 90% or less, preferably 80% or less.

The relative permeability in the circumferential direction of the first region 11 is, for example, 5 or more, preferably 10 or more, more preferably 30 or more, and for example, 500 or less. The relative magnetic permeability in the radial direction is, for example, 1 or more, preferably 5 or more, and for example, 100 or less, preferably 50 or less, and more preferably 25 or less. In addition, the ratio of relative permeability (circumferential direction/radial direction) of the circumferential direction to the radial direction is, for example, 2 or more, preferably 5 or more, and for example, 50 or less. If the relative permeability is in the above range, the inductance is excellent.

The relative permeability can be measured by, for example, an impedance analyzer (manufactured by Agilent, "4291B") using a magnetic material test fixture.

The second region 12 is a circumferential non-aligned region where the anisotropic magnetic particles 8 are not aligned along the circumferential direction of the wiring 2. In other words, in the second region 12, the anisotropic magnetic particles 8 are aligned or not aligned along a direction other than the circumferential direction of the wiring 2 (for example, the first direction or the radial direction).

Two second regions 12 are arranged in the peripheral region 4 at a distance from each other in the circumferential direction. Specifically, the second region 12 includes a fifth region 15 and a sixth region 16, which are arranged at intervals with a first virtual straight line L1 passing through one end edge E1 and the other end edge E2 of the wiring 2 in the thickness direction.

The fifth area 15 is arranged on one side in the first direction with respect to the first virtual straight line L1. The fifth area 15 is sandwiched between one end surface of the third area 13 in the circumferential direction and the other end surface of the fourth area 14 in the circumferential direction. Specifically, it is continuous between one end surface of the third area 13 in the circumferential direction and the fourth area 14 The other end face in the circumferential direction.

The sixth area 16 is disposed on the other side in the first direction opposite to the fifth area 15 at an interval. The sixth area 16 is arranged on the other side in the first direction with respect to the first virtual straight line L1, and is line-symmetrical with respect to the fifth area 15 with the first virtual straight line L1 as an axis. That is, the sixth region 16 is continuous with the other end surface in the circumferential direction of the third region 13 and one end surface in the circumferential direction of the fourth region 14.

Thereby, in the first area 11, the third area 13, the fifth area 15, the fourth area 14, and the sixth area 16 are sequentially arranged in the circumferential direction.

Furthermore, on the second virtual straight line L2 as an example of a virtual straight line connecting the center C3 of the first virtual arc A1, which is an example of a virtual arc, and the center C4 of the second virtual arc A2, which is an example of a virtual arc , There is no center C of the wiring 2, the above-mentioned first imaginary arc A1 connects the first end E5 as one end in the circumferential direction and the second end E6 as the other end in the circumferential direction in the fifth area 15. The above-mentioned second imaginary arc A2 connects the third end E7 as one end in the circumferential direction and the fourth end E8 as the other end in the circumferential direction in the sixth region 16.

In addition, the first end E5 is a portion located at the radial center portion of one end surface in the circumferential direction in the fifth region 15. The second end E6 is a portion located at the radial center portion of the other end surface in the circumferential direction in the fifth region 15. The third end E7 is a portion located at the radial center portion of one end surface in the circumferential direction in the sixth region 16. The fourth end E8 is a portion located at the radial center portion of the other end surface in the circumferential direction in the sixth region 16.

Specifically, the center C of the wiring 2 is arranged on the first direction side of the second virtual straight line L2 at intervals.

In detail, the center C of the wiring 2 is located on the thickness direction side at a distance of 0.2 times or more and 0.7 times the radius R of the wiring 2 compared to the second imaginary straight line L2. For the imaginary straight line L2, a distance of 0.3 times or more and 0.5 times or less of the radius R of the wiring 2 is located on one side in the thickness direction.

Moreover, the other end edge E4 of the thickness direction of the wiring 2 does not exist on the 2nd virtual straight line L2, Specifically, it is located on the other side of the thickness direction of the 2nd virtual straight line L2 with an interval.

Furthermore, in the second region 12 (each of the fifth region 15 and the sixth region 16), at least two types of anisotropic magnetic particles 8 having different alignment directions form an intersection (top) 20. For example, in the fifth area 15, the first particles 17 and the second particles 18 form at least two sides of a substantially triangle, thereby forming a first intersection (first top) 21, and the first particles 17 follow from the first 1 Anisotropic magnetic particles 8 oriented toward the second end E6 (the part contacting the fourth region 14) toward the second end E5 (the part contacting the fourth region 14) toward the radially outer side of the wiring 2. The two particles 18 are anisotropic magnetic particles 8 that are aligned in the first direction from the second end E6 toward the first end E5. Specifically, the first particles 17 and the second particles 18 and the third particles 19 form a substantially triangle (preferably an acute triangle), and the third particles 19 are located along the circumference in the area where the wiring 2 is closest in the fifth area Directionally aligned anisotropic magnetic particles 8.

Moreover, in the sixth region 16, the first particles 17 and the second particles 18 form at least two sides of a substantially triangle, thereby forming a second intersection (second top) 22, and the first particles 17 follow from the first The anisotropic magnetic particles 8 oriented toward the fourth end E8 (the part contacting the third region 13) toward the third end E7 (the part contacting the fourth region 14) toward the radially outer side of the wiring 2. The two particles 18 are anisotropic magnetic particles 8 that are aligned in the first direction from the third end E7 to the fourth end E8. Specifically, the first particle 17 and the second particle 18 and the third particle 19 form a substantially triangle (preferably an acute triangle), and the third particle 19 is located along the circumference in the region where the wiring 2 is closest in the sixth region 16 Directionally aligned anisotropic magnetic particles 8.

When projecting in the first direction, the intersection 20 (each of the first intersection 21 and the second intersection 22) does not overlap the center C of the wiring 2. Specifically, when projecting in the first direction, the intersection portion 20 is arranged at an interval on the other side in the thickness direction from the center C of the wiring 2.

In addition, when projecting in the first direction, the crossing portion 20 is arranged on the thickness direction side of the other end edge E4 of the thickness direction of the wiring 2 at intervals.

In the second region 12 (each of the fifth region 15 and the sixth region 16), the relative magnetic permeability of the anisotropic magnetic particles 8 is higher in the direction (for example, in the case of flat anisotropic magnetic particles, it is The particle surface direction) does not coincide with the tangent to the circumferential surface centered on the center C of the wiring 2. More specifically, the case where the angle between the plane direction of the anisotropic magnetic particle 8 and the outer peripheral surface (circumferential surface) of the wiring 2 where the anisotropic magnetic particle 8 is located exceeds 15 degrees is defined as anisotropic magnetism The particles 8 are not aligned in the circumferential direction.

The ratio of the number of anisotropic magnetic particles 8 not aligned in the circumferential direction to the total number of anisotropic magnetic particles 8 contained in the second region 12 is, for example, more than 50%, preferably 70% or more, and for example, 95% Below, it is preferably 90% or less.

The second region 12 may include, for example, anisotropic magnetic particles 8 aligned in the circumferential direction. The ratio of the number of anisotropic magnetic particles 8 aligned in the circumferential direction to the total number of anisotropic magnetic particles 8 contained in the second region 12 is, for example, less than 50%, preferably 30% or less, and for example, 5 % Or more, preferably 10% or more.

Furthermore, when the anisotropic magnetic particles 8 aligned in the circumferential direction are included, it is preferable to arrange the anisotropic magnetic particles 8 aligned in the circumferential direction in the innermost area of the second area 12, that is, the wiring 2 Near the surface.

The area ratio of the second region 12 (total area of the fifth region 15 and the sixth region 16) relative to the entire peripheral region 4 is, for example, 10% or more, preferably 20% or more, and for example 60% or less, preferably 50% or less, more preferably 40% or less.

Furthermore, in the peripheral region 4, the filling rate (existence ratio) of the anisotropic magnetic particles 8 is, for example, 40% by volume or more, preferably 45% by volume or more, more preferably 50% by volume or more, and even more preferably 55% by volume % Or more, particularly preferably 60% by volume or more. If the filling rate of the anisotropic magnetic particles 8 in the peripheral region 4 is more than the above lower limit, the inductor 1 can obtain excellent inductance.

In addition, the filling rate of the anisotropic magnetic particles 8 in the peripheral region 4 is, for example, 95% by volume or less, preferably 90% by volume or less. If the filling rate of the anisotropic magnetic particles 8 is less than the above upper limit, the inductor 1 has excellent mechanical strength.

In particular, in each of the first region 11 and the second region 12, the filling rate of the anisotropic magnetic particles 8 is, for example, 40% by volume or more, preferably 45% by volume or more, and more preferably 50% by volume or more, Furthermore, it is preferably 55% by volume or more, particularly preferably 60% by volume or more, and for example, 95% by volume or less, and preferably 90% by volume or less.

Furthermore, the filling rate of the anisotropic magnetic particles 8 in the first region 11 and the filling rate of the anisotropic magnetic particles 8 in the second region 12 may be the same or different.

The filling rate of the anisotropic magnetic particles 8 can be calculated by actual specific gravity measurement, binarization of SEM pictures, and the like.

On the other hand, the abundance ratio of the binder 9 in the peripheral region 4 is, for example, the rest of the above-mentioned filling ratio of the anisotropic magnetic particles 8.

In addition, in the peripheral region 4, the formation of voids (voids, gaps) is suppressed as much as possible, and it is preferable that there are no voids between the wiring 2 and the magnetic layer 3. That is, the peripheral area 4 is preferably void-free.

The outer region 5 is the region of the magnetic layer 3 excluding the peripheral region 4. The outer area 5 is arranged on the outer side of the peripheral area 4 and continuous with the peripheral area 4.

In the outer region 5, the anisotropic magnetic particles 8 are aligned along the plane direction (especially the first direction).

In the outer region 5, the direction in which the relative magnetic permeability of the anisotropic magnetic particles 8 is relatively high (for example, in the case of flat anisotropic magnetic particles, the surface direction of the particles) is substantially the same as the first direction. More specifically, the case where the angle between the plane direction of the anisotropic magnetic particles 8 and the first direction is 15° or less is defined as the anisotropic magnetic particles 8 being aligned in the first direction.

In the outer region 5, the ratio of the number of anisotropic magnetic particles 8 aligned in the first direction to the total number of anisotropic magnetic particles 8 contained in the outer region 5 exceeds 50%, preferably 70% or more , More preferably more than 90%. That is, in the outer region 5, less than 50%, preferably 30% or less, and more preferably 10% or less of anisotropic magnetic particles 8 that are not aligned in the first direction may be included.

In addition, the filling rate of the anisotropic magnetic particles 8 in the outer region 5 may be the same as or different from the filling rate of the anisotropic magnetic particles 8 in the peripheral region 4.

In the outer region 5, the relative permeability in the first direction is, for example, 5 or more, preferably 10 or more, more preferably 30 or more, and for example, 500 or less. The relative permeability in the thickness direction is, for example, 1 or more, preferably 5 or more, and for example, 100 or less, preferably 50 or less, and more preferably 25 or less. In addition, the ratio of the relative permeability (first direction/thickness direction) of the first direction to the thickness direction is, for example, 2 or more, preferably 5 or more, and for example, 50 or less.

In the outer region 5, the filling rate of the anisotropic magnetic particles 8 is not particularly limited, for example, 40% by volume or more, preferably 45% by volume or more, more preferably 50% by volume or more, and even more preferably 55% by volume the above. It is particularly preferably 60% by volume or more, and for example, 95% by volume or less, and preferably 90% by volume or less.

The thickness of the magnetic layer 3 is, for example, 2 times or more of the radius R of the wiring 2, preferably 3 times or more, and for example 20 times or less. Specifically, the thickness of the magnetic layer 3 is, for example, 100 μm or more, preferably 200 μm or more, and for example, 2000 μm or less, preferably 1000 μm or less. Furthermore, the thickness of the magnetic layer 3 is the distance between one surface of the magnetic layer 3 and the other surface.

2. Manufacturing method of inductor The method of manufacturing the inductor 1 will be described with reference to FIGS. 2A to 3F.

The manufacturing method of the inductor 1 includes the first step to the sixth step. In the manufacturing method of the inductor 1, the first step, the second step, and the third step are sequentially performed, and then the fourth step, the fifth step, and the sixth step are simultaneously performed.

(Step 1) As shown in FIG. 2A, in the first step, first, the wiring 2 and the first release sheet 41 as a release film are prepared. The first release sheet 41 is an example of a substrate.

The first release sheet 41 has a substantially sheet shape extending in the surface direction. The material of the first release sheet 41 is appropriately selected according to its use and purpose. Specifically, for example, polyesters such as polyethylene terephthalate (PET), such as polymethylpentene, polypropylene, etc. And other polyolefins. In addition, one surface and/or the other surface of the first release sheet 41 in the thickness direction may be subjected to release treatment. The thickness of the first release sheet 41 is, for example, 1 μm or more, and for example, 1000 μm or less.

After that, in the first step, the wiring 2 and the first release sheet 41 are arranged on the flat plate press 42.

The plate pressing machine 42 includes a first plate 43 and a second plate 44 that can be pressurized in the thickness direction. In the flat plate press 42, the second plate 44 is opposingly arranged on one side in the thickness direction of the first plate 43 at an interval. In addition, the plate press 42 has a heat source not shown.

In addition, the plate press 42 is provided with a chamber, and the chamber is used to make the components arranged in the plate press 42 and supplied to the press in a vacuum state.

In the first step, first, the first release sheet 41 is placed on the first plate 43, and then the wiring 2 is placed on one surface of the first release sheet 41 in the thickness direction. Specifically, the other end edge E4 in the thickness direction of the wiring 2 is brought into contact with one surface of the first release sheet 41.

In addition, at this time, the first release sheet 41 and the first plate 43 are arranged in the cavity. All the components arranged in the subsequent steps are arranged in the chamber.

(Step 2) In the second step, first, as shown in FIG. 2A, the first magnetic sheet 51 is prepared. At the same time, a second release sheet 45 and a release buffer sheet 46 are prepared.

[First Magnetic Sheet] The first magnetic sheet 51 has a substantially sheet shape extending in the surface direction. Specifically, the first magnetic sheet 51 has one surface and the other surface facing each other in the thickness direction.

The first magnetic sheet 51 is a magnetic sheet for forming at least the second region 12, the third region 13 (a part or all of it), and a part of the outer region 5 in the magnetic layer 3.

Furthermore, the first magnetic sheet 5 is configured to be deformed (flowed) by the hot pressing in the second step (see FIG. 2B).

In addition, the first magnetic sheet 51 contains first anisotropic magnetic particles 81 and a first binder 91 as an example of the first magnetic particles. The first anisotropic magnetic particle 81 is the same as the anisotropic magnetic particle 8. Specifically, the first magnetic sheet 51 is formed into a substantially sheet shape from the first magnetic composition containing the first anisotropic magnetic particles 81 and the first binder 91.

In the first magnetic sheet 51, the first anisotropic magnetic particles 81 are uniformly dispersed by the first binder 91 so as to be aligned in the plane direction.

The first magnetic sheet 51 is a single sheet or a laminate of a plurality of sheets (laminated sheet), preferably a laminated sheet, more preferably a 2-layer sheet including an inner sheet 54 and an outer sheet 55 The inner sheet 54 is in contact with the wiring 2 during hot pressing, and the outer sheet 55 is arranged on one side in the thickness direction of the inner sheet.

The volume ratio of the first anisotropic magnetic particles 81 in the first magnetic composition (the first magnetic sheet 51) is, for example, 40% by volume or more, preferably 45% by volume or more, more preferably 50% by volume or more, and further It is preferably 55% by volume or more, particularly preferably 60% by volume or more, and for example, 95% by volume or less, preferably 90% by volume or less. If the volume ratio of the first anisotropic magnetic particles 81 is in the above range, the first anisotropic magnetic particles 81 can be densely arranged in the peripheral region 4. Thereby, an inductor 1 with excellent inductance can be obtained.

In addition, the volume ratio of the first anisotropic magnetic particles 81 in the first magnetic composition (first magnetic sheet 51) is also preferably 40% by volume or less, further 35% by volume or less, and 20% by volume or more. , And further more than 25% by volume. If the volume ratio of the first anisotropic magnetic particles 81 is in the above range, the existence of pores in the peripheral region 4 can be suppressed as much as possible. Therefore, in the peripheral region 4, the first anisotropic magnetic particles 81 and The second anisotropic magnetic particles 82 and the third anisotropic magnetic particles 83 (described below) are densely arranged together. As a result, an inductor 1 with excellent inductance can be obtained.

If the first magnetic sheet 51 is a two-layer laminated sheet of the inner sheet 54 and the outer sheet 55, the volume ratio of the anisotropic magnetic particles 8 of the outer sheet 55 is preferably higher than the volume of the inner sheet 54 ratio. In this way, the first magnetic sheet 51 can more flexibly follow the area of the circumferential surface of the wiring 2 that exceeds 180° when viewed in section (hereinafter referred to as a major arc).

Examples of the first adhesive 91 include thermoplastic components such as acrylic resins, and thermosetting components such as epoxy resin compositions. The acrylic resin includes, for example, a carboxyl group-containing acrylate copolymer. The epoxy resin composition contains, for example, an epoxy resin (for example, a cresol novolak type epoxy resin, etc.) as a main agent, a hardener for epoxy resin (for example, a phenol resin, etc.), and a hardening accelerator for epoxy resin ( For example, imidazole compounds, etc.).

As the first binder 91, a thermoplastic component and a thermosetting component may be used alone or in combination, and a thermoplastic component and a thermosetting component are preferably used in combination.

That is, it is preferable that the first adhesive 91 contains at least a thermosetting component. If the first binder 91 contains at least a thermosetting component, the first magnetic sheet 51 can be made into a B-stage with fluidity, and the first anisotropic magnetic particles 81 can be uniformly dispersed at a high mixing ratio. In the second step of hot pressing, the first magnetic sheet 51 can be flexibly deformed, and follows and covers the superior arc at the circumferential surface of the wiring 2.

Furthermore, a more detailed formulation of the first adhesive 91 (first magnetic composition) is described in Japanese Patent Laid-Open No. 2014-165363 and the like.

The volume ratio of the first binder 91 in the first magnetic composition (the first magnetic sheet 51) is the remainder of the volume ratio of the magnetic particles 48 described above.

In order to produce the first magnetic sheet 51, the first anisotropic magnetic particles 81 and the first binder 91 are prepared, and they are uniformly mixed to prepare a first magnetic composition. At this time, a solvent (organic solvent) is used as needed to prepare the varnish of the first magnetic composition. After that, a varnish is applied to a release film (not shown) and dried to produce the first magnetic sheet 51.

The thickness of the first magnetic sheet 51 (in the case of a laminated sheet, the total thickness) is appropriately set to maintain a shape that can cover at least one end E1 of the wiring 2 in the thickness direction of the outer region 5 by the second step of hot pressing . Specifically, the thickness of the first magnetic sheet 51 is, for example, 3 times or less of the radius R of the wiring 2, preferably 2 times or less, more preferably less than 2 times, more preferably 1.5 times or less, and particularly preferably 1.25 times or less, and, for example, 0.1 times or more, preferably 0.2 times or more.

(Second release sheet) The second release sheet 45 has the same configuration as the first release sheet 41, and from the above, the material is appropriately selected according to the application and purpose.

(Release buffer sheet) The release buffer sheet 46 is a release sheet that can separate the first magnetic sheet 51 from the second plate 44 after hot pressing (see FIG. 2C) in the second step described later. In addition, the release buffer sheet 46 is also a buffer sheet for the following purposes. During the hot pressing in the second step (refer to FIG. 2B), the pressure of the second plate 44 corresponds to the superiority of the circumferential surface of the wiring 2. The shape of the arc acts on the first magnetic sheet 51 in a dispersed manner to deform the first magnetic sheet 51 so that the first magnetic sheet 51 follows the superior arc of the circumferential surface of the wiring 2.

The release buffer sheet 46 has a sheet shape extending in the surface direction, and has one surface and the other surface in the thickness direction.

One surface of the release buffer sheet 46 may be in surface contact with the second plate 44 (described below) in the second step. One surface of the release buffer sheet 46 is a flat surface along the surface direction.

The other surface of the release buffer sheet 46 can be in contact with a surface in the thickness direction of the second release sheet 45 to deform the first magnetic sheet 51. The other surface of the release buffer sheet 46 is oppositely arranged on the other side in the thickness direction with an interval therebetween. The other surface of the release buffer sheet 46 is parallel to one surface and a flat surface along the surface direction.

The release cushion sheet 46 includes a first layer 47, a second layer 48, and a third layer 49 in this order on one side in the thickness direction.

(Level 1) The first layer 47 is a release layer (first release layer) for the first magnetic sheet 51. The first layer 47 is a thin film (film) having a shape extending along the surface direction. In addition, the first layer 47 covers the coating layer (shell layer) of the second layer 48 described later from the other side in the thickness direction. The other surface of the first layer 47 in the thickness direction may be appropriately peeled off.

The first layer 47 has the following physical properties: in the subsequent second step of hot pressing, it can follow one surface of the first magnetic sheet 51 through the second release sheet 45. On the other hand, its thickness is lower than that of the hot pressing. There is essentially no change before and after. In addition, the first layer 47 is a layer that can be stretched in the surface direction (specifically, the first direction) during hot pressing. Furthermore, the first layer 47 is harder than the second layer 48 described later at the hot pressing temperature (for example, 110° C.) in the second step.

As the material of the first layer 47, a non-heat-fluid material can be cited, and the non-heat-fluid material does not flow in at least the first direction by the hot pressing in the second step described below.

The non-heat-flowing material contains, for example, aromatic polyester such as polybutylene terephthalate (PBT), and, for example, polyolefin as main components.

(Level 2) The second layer 48 is an intermediate layer sandwiched between the first layer 47 and the third layer 49. The second layer 48 is a fluidized layer, which flows in the first direction and the thickness direction during the hot pressing in the first step, so that the first layer 47 follows one surface of the first magnetic sheet 51.

The second layer 48 is a softer layer that is softer than the first layer 47. Specifically, it can be deformed during the hot pressing in the second step. Specifically, the tensile storage modulus E'of the second layer 48 at 110° C. is lower than the tensile storage modulus E'of the first layer 47 at 110° C., for example.

As the material of the second layer 48, a heat-fluid material that flows in the first direction and the thickness direction by hot pressing in the second step described below can be cited. The heat flow material contains, for example, an olefin-(meth)acrylate copolymer (ethylene-methyl (meth)acrylate copolymer, etc.), an olefin-vinyl acetate copolymer, or the like as a main component.

(Level 3) The third layer 49 is a release layer (second release layer) for the second plate 44. The shape, physical properties, material, and thickness of the third layer 49 are the same as those of the first layer 47.

(Thickness of release buffer sheet) The thickness of the release buffer sheet 46 is, for example, 50 μm or more, and for example, 500 μm or less. The thickness of the first layer 47 and the third layer 49 is, for example, 5 μm or more and 50 μm or less, and the thickness of the second layer 48 is, for example, 30 μm or more and 300 μm or less. The ratio of the thickness of the second layer 48 to the thickness of the first layer 47 is, for example, 2 or more, preferably 5 or more, more preferably 7 or more, and for example, 15 or less.

For the release buffer sheet 46, commercially available products can be used, for example, release film OT series (manufactured by Sekisui Chemical Industry Co., Ltd.) such as release film OT-A and release film OT-E.

Then, the first release sheet 41, the wiring 2, the first magnetic sheet 51, the second release sheet 45, and the release buffer sheet 46 are clamped in this order by the flat plate press 42.

Then, the first release sheet 41, the second release sheet 45, and the release buffer sheet 46 are interposed by the flat plate press 42 to heat-press the wiring 2 and the first magnetic sheet 51.

For example, the second plate 44 is moved so as to approach the first plate 43, and the second plate 44 is pressed (pressurized) against the first magnetic sheet 51 through the isolation buffer sheet 46 and the second release sheet 45 .

At the same time, the first magnetic sheet 51 and the release buffer sheet 46 are heated by a heat source.

The pressurizing pressure is, for example, 0.1 MPa or more, preferably 0.3 MPa or more, and for example, 10 MPa or less, preferably 5 MPa or less.

Specifically, the heating temperature is, for example, 100°C or higher, preferably 105°C or higher, and, for example, 190°C or lower, preferably 150°C or lower.

The pressing time is, for example, 10 seconds or more, preferably 20 seconds or more, and for example, 1000 seconds or less, preferably 100 seconds or less.

In the second step, the chamber is closed by moving the second plate 44 relative to the first plate 43, and then the environment in the chamber is vacuumed. Then, the first plate 43 and the first release sheet 41. Wiring 2, the first magnetic sheet 51, the second release sheet 45, the release buffer sheet 46, and the second plate 44. The members adjacent to each other in the thickness direction are in contact with each other (close contact, close contact), and then , The second plate 44 moves further (the hot pressing starts).

Therefore, when projecting in the thickness direction, the overlapped portion 34 of the release cushion sheet 46 overlapping the wiring 2 is narrowed in the thickness direction by the first semicircular arc surface 23 and the second plate 44 of the wiring 2. Squeeze (clamp).

On the other hand, when projecting in the thickness direction, the non-overlapping portion 35 of the release cushion sheet 46 that does not overlap with the wiring 2 will not be subjected to the aforementioned pinching pressure.

Then, the hot-fluid material in the overlapping portion 34 of the second layer 48 flows (extrudes) (deforms) (specifically, plastic deformation) toward the non-overlapping portion 35. Therefore, in the non-overlapping portion 35, the flow pressure based on the flow (extrusion) of the hot flowing material from the aforementioned overlapping portion 34 increases. The flow pressure of the non-overlapping part 35 acts on both sides of the thickness direction.

Among the flow pressures, the flow pressure acting on the other side of the thickness direction extrudes (presses down) the first layer 47 of the non-overlapping portion 35 toward the other side of the thickness direction, and interposes the first layer 47 to push the first magnetic sheet The extruded part 38 of the material 51 facing the non-overlapping part 35 in the thickness direction is extruded (pressed) toward the other side in the thickness direction.

Thereafter, the extrusion (pressing) of the extruded portion 38 based on the above-mentioned flow pressure continues until the extruded portion 38 wraps the both ends E3 and E4 of the wiring 2 in the first direction, and then covers (contacts) the wiring 2 To the second arc surface 24 (except for the other end edge E4 in the thickness direction).

Then, as the extruded portion 38 contacts the second arc surface 24, as shown in FIG. 2B, the second region 12 is formed.

After hot pressing, the other surface of the release buffer sheet 46 has, for example, a shape corresponding to the first semicircular arc surface 23 of the wiring 2.

The second release sheet 45 follows the other surface of the release buffer sheet 46, and specifically follows the first layer 47.

Furthermore, the first magnetic sheet 51 after hot pressing is, for example, B-stage. Specifically, the thermosetting component contained in the first adhesive 91 of the first magnetic sheet 51 is a B-stage.

Thereby, the first magnetic sheet 51 after hot pressing has a shape including at least the second region 12 described above. That is, as shown in the enlarged view of FIG. 2B, in the second region 12, the anisotropic magnetic particles 8 are not aligned along the circumferential direction of the wiring 2.

In addition, the first magnetic sheet 51 has a raised portion 25 and a flat portion 26.

The raised portion 25 covers the outer peripheral surface of the wiring 2 (except for the other end edge E4 in the thickness direction), and has a cross-sectional curved shape similar to (or similar to) the first semicircular arc surface 23. The raised portion 25 has a shape in which the center in the first direction protrudes (swells) toward one side in the thickness direction. The raised portion 25 has a second top portion 27.

The flat portion 26 has a substantially flat plate shape extending from both ends of the raised portion 25 in the first direction toward both outer sides in the first direction, respectively.

Thereby, the first magnetic sheet 51 is arranged on one surface of the first release sheet 41 in the thickness direction in a manner of covering the superior arc of the circumferential surface of the wiring 2.

The superior arc of the circumferential surface of the wiring 2 is the arc from the first semicircular arc surface 23 and each of its ends in the circumferential direction along the circumferential direction to the other end edge E4 in the thickness direction, but does not reach the other end edge E4 in the thickness direction Surface (part of the circumferential surface).

The thickness of the first magnetic sheet 51 after hot pressing is set so as to ensure the shape of the raised portion 25 and the flat portion 26 described above. Specifically, the ratio of the thickness at the second top portion 27 of the first magnetic sheet 51 to the radius R of the wiring 2 is, for example, 0.01 or more, preferably 0.03 or more, and for example, 8 or less, preferably 2 or less. The ratio of the thickness of the flat portion 26 to the radius R of the wiring 2 is, for example, 0.05 or more, preferably 0.2 or more, and for example, less than 5, preferably 1.5 or less.

Specifically, the thickness at the second top portion 27 of the first magnetic sheet 51 is, for example, 1 μm or more, preferably 5 μm or more, and for example, 200 μm or less, preferably 100 μm or less. In addition, the thickness of the flat portion 26 is, for example, 25 μm or more, preferably 50 μm or more, and for example, 200 μm or less, preferably 150 μm or less.

(Step 3) In the third step, first, the pressurization of the flat plate press 42 shown in FIG. 2B is released, and then the first release sheet 41, wiring 2, first magnetic sheet 51, and The second release sheet 45 and the release buffer sheet 46.

Then, as shown in FIG. 2C, the first release sheet 41 is peeled from the other surface of the first magnetic sheet 51 and the other end edge E4 of the wiring 2 in the thickness direction.

In addition, the second release sheet 45 and the release buffer sheet 46 are peeled from one surface of the first magnetic sheet 51.

(Step 4, Step 5, and Step 6) As shown in FIG. 3E, the fourth step, the fifth step, and the sixth step are simultaneously performed.

In the fourth step, one surface of the first magnetic sheet 51 in the thickness direction is covered by the second magnetic sheet 52. In the fifth step, the other surface of the first magnetic sheet 51 in the thickness direction is covered by the third magnetic sheet 53. In the sixth step, the thermosetting component C of the first adhesive 91 (see FIG. 2A), the second adhesive 92 (see FIG. 3D), and the third adhesive 93 (see FIG. 3D) are staged.

As shown in FIG. 3D, in the fourth step and the fifth step, first, the second magnetic sheet 52 and the third magnetic sheet 53 are prepared.

Each of the second magnetic sheet 52 and the third magnetic sheet 53 may have the same structure as the first magnetic sheet 51.

Furthermore, the second magnetic sheet 52 contains second anisotropic magnetic particles 82 and a second binder 92. In the second binder 92, for example, the second anisotropic magnetic particles 82 are aligned in the plane direction. The thermosetting component contained in the second adhesive 92 is in the B stage, so the second magnetic sheet 52 is in the B stage. In addition, if the second magnetic sheet 52 is a laminate (laminated sheet), the abundance ratio of the second anisotropic magnetic particles 82 in each sheet is the same or different, and preferably the same. In addition, the abundance ratio of the second anisotropic magnetic particles 82 in the second magnetic sheet 52 may be the same as or different from the abundance ratio of the first anisotropic magnetic particles 81.

When the existence ratio of the second anisotropic magnetic particles 82 is different from the existence ratio of the first anisotropic magnetic particles 81, and the existence ratio of the first anisotropic magnetic particles 81 is 40% by volume or less, the second The existence ratio of the anisotropic magnetic particles 82 is set to be higher than the existence ratio of the first anisotropic magnetic particles 81. Specifically, the ratio of the existence ratio of the second anisotropic magnetic particles 82 in the second magnetic sheet 52 to the existence ratio of the first anisotropic magnetic particles 81 in the first magnetic sheet 51 (the second magnetic sheet The abundance ratio of the second anisotropic magnetic particles 82 in the material 52/the abundance ratio of the first anisotropic magnetic particles 81 in the first magnetic sheet 51) is, for example, 1.1 or more, preferably 1.2 or more, more preferably 1.5 or more, and for example 3 or less, preferably 2.5 or less. In this case, specifically, the abundance ratio of the second anisotropic magnetic particles 82 in the second magnetic sheet 52 is, for example, 45% by volume or more, preferably 50% by volume or more, more preferably 55% by volume or more , More preferably 60% by volume or more, and for example, 95% by volume or less, more preferably 90% by volume or less.

If the above-mentioned ratio and/or the existence ratio of the second anisotropic magnetic particles 82 are within the above-mentioned range, the existence of voids between the second magnetic sheet 52 and the first magnetic sheet 51 can be suppressed as much as possible. Therefore, the first anisotropic magnetic particles 81 and the second anisotropic magnetic particles 82 can be densely arranged in the peripheral region 4. As a result, an inductor 1 with excellent inductance can be obtained.

The thickness of the second magnetic sheet 52 (in the case of a laminated sheet, the total thickness) is, for example, 0.5 times or more of the radius R of the wiring 2, preferably 1 time or more, more preferably 1.5 times or more, and for example, 5 times Below, it is preferably 3 times or less.

The third magnetic sheet 53 contains third anisotropic magnetic particles 83 and a third binder 93 as an example of the third magnetic particles. For example, in the third binder 93, the third anisotropic magnetic particles 83 are on the surface. Alignment in the direction. The thermosetting component contained in the third adhesive 93 is in the B stage, so the third magnetic sheet 53 is in the B stage. In addition, if the third magnetic sheet 53 is a laminate (laminated sheet), the abundance ratios of each sheet and the third anisotropic magnetic particles 83 are the same or different, and preferably the same. In addition, the abundance ratio of the third anisotropic magnetic particles 83 in the third magnetic sheet 53 may be the same as or different from the abundance ratio of the first anisotropic magnetic particles 81.

When the existence ratio of the third anisotropic magnetic particles 83 is different from the existence ratio of the first anisotropic magnetic particles 81, and the existence ratio of the first anisotropic magnetic particles 81 is 40% by volume or less, the third anisotropic magnetic particles The existence ratio of the anisotropic magnetic particles 83 is set to be higher than the existence ratio of the first anisotropic magnetic particles 81. Specifically, the ratio of the existence ratio of the third anisotropic magnetic particles 83 in the third magnetic sheet 53 to the existence ratio of the first anisotropic magnetic particles 81 in the first magnetic sheet 51 (the third magnetic sheet The ratio of the existence of the third isotropic magnetic particles 83 in the material 53/the ratio of the existence of the first anisotropic magnetic particles 81 in the first magnetic sheet 51) is, for example, 1.1 or more, preferably 1.2 or more, more preferably 1.5 or more, and for example 2.5 or less, preferably 2 or less. In this case, specifically, the abundance ratio of the third anisotropic magnetic particles 83 in the third magnetic sheet 53 is, for example, 40% by volume or more, preferably 45% by volume or more, more preferably 50% by volume or more , More preferably 55% by volume or more, particularly preferably 60% by volume or more, and for example, 95% by volume or less, preferably 90% by volume or less.

If the above-mentioned ratio and/or the abundance ratio of the third anisotropic magnetic particles 83 are within the above-mentioned range, the existence of voids between the third magnetic sheet 53 and the first magnetic sheet 51 can be suppressed as much as possible. As a result, The first anisotropic magnetic particles 81 and the third anisotropic magnetic particles 83 are densely arranged in the peripheral region 4. Therefore, an inductor 1 with excellent inductance can be obtained.

The thickness of the third magnetic sheet 53 (in the case of a laminated sheet, the total thickness) is, for example, 0.5 times or more of the radius R of the wiring 2, preferably 1 time or more, and for example, 5 times or less, preferably 3 times the following.

Subsequently, the second magnetic sheet 52 and the third magnetic sheet 53 are arranged on the flat plate press 42. Specifically, between the first plate 43 and the second plate 44, the first release sheet 41, the third magnetic sheet 53, the wiring 2 and the first magnetic sheet 51 are arranged in this order toward one side in the thickness direction. The second magnetic sheet 52 and the second release sheet 45.

Furthermore, the first release sheet 41 and/or the second release sheet 45 can reuse the first release sheet 41 and/or the second release sheet 45 removed in the third step, and The other first release sheet 41 and/or the second release sheet 45 may be prepared and arranged.

Furthermore, in the hot pressing of the fourth step and the fifth step, the release buffer sheet 46 used in the second step is not placed on the flat press 42.

Subsequently, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, and the second magnetic sheet 52 are hot-pressed by a flat press. The conditions of hot pressing are the same as those in the second step.

The other surface of the second magnetic sheet 52 follows the shape of the raised portion 25 of the first magnetic sheet 51 by hot pressing. However, one surface of the second magnetic sheet 52 maintains its flat shape.

That is, the second magnetic sheet 52 covers one surface of the first magnetic sheet 51 in the thickness direction, and the first magnetic sheet 51 covers the superior arc of the circumferential surface of the wiring 2 and one surface of the first release sheet 41 (implementation Step 4).

In addition, the other surface of the third magnetic sheet 53 maintains its flat shape by hot pressing.

On the other hand, on one surface of the third magnetic sheet 53, the facing portion 28 facing the other end edge E4 in the thickness direction of the wiring 2 slightly moves (retreats, descends, sinks) to the other side in the thickness direction. That is, on one surface of the third magnetic sheet 53, the facing portion 28 moves outward in the first direction, and is in the thickness direction relative to the second flat portion 29 parallel to the surface of the first release sheet 41. One side is slightly concave.

The other surface of the first magnetic sheet 51 is in close contact with the second flat portion 29 of one surface of the third magnetic sheet 53, and the other end edge E4 of the wiring 2 in the thickness direction is slightly moved toward one side in the thickness direction.

That is, the third magnetic sheet 53 is arranged on the first magnetic sheet 51 so as to cover the circumferential surface of the wiring 2 (including the arc surface of the other end edge E4 in the thickness direction) exposed from the other surface of the first magnetic sheet 51 in the thickness direction. The other surface in the thickness direction of the magnetic sheet 51 (the fifth step is performed).

Thereby, when projecting in the thickness direction, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, and the second magnetic sheet are sequentially arranged toward the thickness direction side in the portion overlapping the wiring 2 52. In addition, when projecting in the thickness direction, the third magnetic sheet 53, the first magnetic sheet 51, and the second magnetic sheet 52 are sequentially arranged toward the thickness direction side in the portion that does not overlap the wiring 2.

By the above-mentioned hot pressing, the sixth step is performed simultaneously with the fourth step and the fifth step.

The conditions of the hot pressing are selected so that the thermosetting properties of the first adhesive 91, the second adhesive 92, and the third adhesive 93 can be C-staged.

In this sixth step, the first adhesive 91 in the first magnetic sheet 51, the second adhesive 92 in the second magnetic sheet 52, and the third adhesive 93 in the third magnetic sheet 53 are The above-mentioned hot pressing is C-staged.

Therefore, the adhesive 9 contains a cured product of a B-stage thermosetting component (C-stage product).

Furthermore, by the C-stageization of the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53, the boundary between the first magnetic sheet 51 and the second magnetic sheet 52, and the first magnetic sheet The boundary between the sheet 51 and the third magnetic sheet 53 disappears, and one magnetic layer 3 including the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53 is formed (see FIG. 1A). However, the above boundary is described in FIG. 3F in order to clearly show the arrangement of the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53.

3. Purpose Inductor 1 is a part of an electronic machine, that is, a part used to make an electronic machine, and does not include electronic components (chips, capacitors, etc.) or mounting substrates for mounting electronic components, but is circulated as a single part. Devices used in industry.

The inductor 1 is mounted (assembled) in an electronic device or the like, for example. Although not shown, the electronic equipment includes a mounting substrate and electronic components (chips, capacitors, etc.) mounted on the mounting substrate. In addition, the inductor 1 is mounted on a mounting substrate via connecting members such as solder, is electrically connected to other electronic devices, and functions as a passive element such as a coil.

Furthermore, in this method, as shown in FIG. 2B, in the second step, the first magnetic sheet 51 is arranged on one surface of the first release sheet 41 in the thickness direction in a manner to cover the superior arc of the wiring 2, and Therefore, the anisotropic magnetic particles 8 can be aligned along the circumferential direction of the wiring 2 in the first magnetic sheet 51 covering the region corresponding to the superior arc of the wiring 2. Therefore, the obtained inductor 1 is excellent in inductance.

In the second step, the first magnetic sheet 51 is arranged on one surface of the first release sheet 41 in the thickness direction. Therefore, in the first magnetic sheet 51, the first anisotropic magnetic particles 81 are along The thickness direction of the first release sheet 41 has a surface alignment. Therefore, it is possible to suppress the first anisotropic magnetic field in the circumferential end edges in the area facing the thickness direction of the first release sheet 41 and corresponding to the superior arc of the wiring 2, that is, the second area 12 The particles 81 are aligned along the circumferential direction of the wiring 2, and therefore, the inductor 1 has excellent DC superimposition characteristics.

In addition, since the first magnetic sheet 51 covers the superior arc of the circumferential surface of the wiring 2, at both ends of the superior arc in the circumferential direction, the alignment direction of the first anisotropic magnetic particles 81 can be made from the circumferential direction of the wiring 2. The change is along the direction of one surface of the first release sheet 41 and the first anisotropic magnetic particles 81 are densely arranged. As a result, an inductor 1 with excellent inductance can be manufactured.

Furthermore, as shown in FIG. 3F, in the fourth step, the second magnetic sheet 52 covers one surface of the first magnetic sheet 51 in the thickness direction, so that the peripheral region 4 of the wiring 2 can include the first anisotropy The anisotropic magnetic particles 8 of the magnetic particles 81 and the second anisotropic magnetic particles 82 are densely arranged. Therefore, an inductor 1 with more excellent inductance can be manufactured.

Therefore, according to this manufacturing method, the anisotropic magnetic particles 8 in the peripheral region 4 can be densely arranged, so that the inductor 1 having excellent inductance and excellent DC superimposition characteristics can be manufactured.

Furthermore, in this method, as shown in FIG. 3F, the third magnetic sheet 53 is further arranged on the other surface of the first magnetic sheet 51 in the thickness direction, so that the peripheral region 4 of the wiring 2 can include the first The anisotropic magnetic particles 81, the second anisotropic magnetic particles, and the third anisotropic magnetic particles 83 are densely arranged. Therefore, an inductor 1 with more excellent inductance can be manufactured.

In particular, since the third magnetic sheet 53 covers the circumferential surface exposed from the other surface of the first magnetic sheet 51 in the thickness direction, it can be located in the area corresponding to the circumferential surface of the wiring 2 exposed from the first magnetic sheet 51 Among them, the third anisotropic magnetic particles 83 are densely arranged. As a result, an inductor 1 with excellent inductance can be manufactured.

In addition, in this method, the fourth step and the fifth step are simultaneously performed, and therefore, the manufacturing time can be shortened compared with the method of sequentially performing the fourth step and the fifth step (refer to the following modification example). Therefore, the inductor 1 can be manufactured efficiently.

In this method, in the sixth step, the B-stage thermosetting components of the first adhesive 91 and the third adhesive 93 are simultaneously C-staged, so that the first adhesive 91 and the third adhesive are sequentially The B-stage thermosetting component of 93 can shorten the manufacturing time compared to the C-stage method (refer to the following modification example) (refer to the following modification example). Therefore, the inductor can be manufactured efficiently.

<Variations of the first embodiment> In the modified example, the same reference numerals are attached to the same members and steps as in the first embodiment, and detailed descriptions thereof are omitted. In addition, the modified example exhibits the same functions and effects as the first embodiment except for special descriptions. Furthermore, the first embodiment and its modification examples can be appropriately combined.

In the first embodiment, the fourth step and the fifth step are implemented simultaneously with the sixth step. However, steps 4 and 5 can be implemented, and then step 6 can be implemented.

In the first embodiment, the fourth step and the fifth step are implemented simultaneously. However, the fourth step and the fifth step can also be performed in sequence. Specifically, in this modified example, as shown in FIGS. 4A to 6H, the first step, the second step, the fourth step, the third step, the fifth step, and the sixth step are sequentially performed.

As shown in FIG. 4A, in the first step, the wiring 2 is arranged on one surface of the first release sheet 41 in the thickness direction.

Subsequently, as shown in FIG. 4B, in the second step, the first release sheet 41, the wiring 2, the first magnetic sheet 51, the second release sheet 45, and the release sheet are clamped by the flat plate press 42 The buffer sheet 46, and subsequently, the wiring 2 and the first magnetic sheet 51 are heat-pressed by the flat press 42 through the first release sheet 41, the second release sheet 45, and the release buffer sheet 46 . Thereby, the first magnetic sheet 51 is arranged on one surface of the first release sheet 41 in the thickness direction in a manner to cover the superior arc of the circumferential surface of the wiring 2.

Subsequently, as shown in FIG. 5D, the fourth step is implemented. Specifically, first, the pressurization of the flat plate press 42 shown in FIG. 4B is released, and then, as shown in FIG. 4C, the first release sheet 41, the wiring 2, and the first magnetic sheet 51 are arranged on In the state of the flat plate press 42, the second release sheet 45 and the release buffer sheet 46 are taken out from the flat press 42.

After that, in the fourth step, the second magnetic sheet 52 and the second release sheet 45 are separately arranged on one side in the thickness direction of the first magnetic sheet 51.

Then, as shown in FIG. 5D, the second magnetic sheet 52 is heat-pressed using a flat press 42. Thereby, the second magnetic sheet 52 covers one surface of the first magnetic sheet 51.

As shown in Fig. 6G, the third step is implemented. Specifically, first, the pressurization of the flat plate press 42 shown in FIG. 5D is released, and the first release sheet 41, wiring 2, first magnetic sheet 51, and second magnetic sheet are taken out from the flat press 42 The material 52 and the second release sheet 45.

In the third step, then, as shown in FIG. 5E, the first release sheet 41 is peeled from the other surface of the first magnetic sheet 51 and the other end edge E4 of the wiring 2 in the thickness direction.

Subsequently, as shown in FIG. 5F, the fifth step is implemented.

Specifically, in the fifth step, the first release sheet 41, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, the second magnetic sheet 52, and the second release sheet 45 It is arranged in the plate press 42.

In the fifth step, as shown in FIG. 6G, the third magnetic sheet 53 is hot-pressed by a flat press 42. Thereby, the third magnetic sheet 53 is arranged on the other surface of the first magnetic sheet 51 in the B stage so as to cover the other end edge E4 in the thickness direction of the wiring 2. At this time, the other end edge E4 in the thickness direction of the wiring 2 sinks into the opposing portion.

Perform the sixth step after the fifth step or simultaneously with the fifth step. Specifically, the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53 are C-staged, and the C-stage magnetic layer 3 is formed. Thereby, the inductor 1 provided with the magnetic layer 3 of the wiring 2 and the covering wiring 2 is obtained.

After that, as shown in FIG. 6H, the inductor 1 is taken out from the plate pressing machine 42.

Among the modified examples and the first embodiment, the first embodiment is preferable. In the first embodiment, since the fourth step and the fifth step are performed at the same time, the number of manufacturing steps can be reduced, and the inductor 1 can be easily manufactured.

In the second step of the first embodiment, as shown in FIG. 2B, the second release sheet 45 is placed on the flat plate press 42, but the second release sheet 45 may not be placed and hot pressing may be performed.

In the second magnetic sheet 52, the second anisotropic magnetic particles 82 are aligned in the plane direction, but the second anisotropic magnetic particles 82 may not be aligned in the plane direction.

<The second embodiment> In the second embodiment, the same reference numerals are attached to the same members and steps as in the first embodiment and its modifications, and detailed descriptions thereof are omitted. In addition, the second embodiment can exhibit the same effects as those of the first embodiment and its modifications except for special descriptions. Furthermore, it is possible to appropriately combine the first embodiment, the second embodiment, and modification examples thereof.

In the first embodiment shown in FIGS. 1A to 1B, when projecting in the thickness direction, the intersection 20 is arranged at intervals on the thickness direction side of the other end edge E4 of the wiring 2 in the thickness direction, for example, as shown in FIG. As shown in 7A to 7B, it may overlap with the other end edge E4 of the wiring 2 in the thickness direction.

As shown in FIGS. 7A to 7B, the fourth area 14 of the inductor 1 of the second embodiment is narrower than the fourth area 14 of the inductor 1 of the first embodiment. Specifically, the angle α2 of the central angle C2 of the fourth region 14 is less than 15° and exceeds 0°.

Next, a method of manufacturing the inductor 1 will be described with reference to FIGS. 8A to 9F.

The method of manufacturing the inductor 1 includes the first to sixth steps. In the manufacturing method of the inductor 1, the first step, the second step, and the third step are sequentially performed, and then the fourth step and the fifth step are simultaneously performed. In addition, the sixth step is performed in batches, and specifically, it is divided into the hot pressing in the second step and the hot pressing in the fourth and fifth steps.

(Step 1) As shown in FIG. 8A, in the first step, the wiring 2 is arranged on one surface of the first release sheet 41 in the thickness direction.

(Part of Step 2 and Step 6) Subsequently, as shown in FIG. 8B, the first release sheet 41, the wiring 2, the first magnetic sheet 51, the second release sheet 45, and the release buffer sheet are sequentially clamped by the flat press 42 46. Then, the first magnetic sheet 51 is hot-pressed by the flat plate press 42. Thereby, the first magnetic sheet 51 is arranged on one surface of the first release sheet 41 in the thickness direction in a manner of covering the superior arc of the circumferential surface of the wiring 2.

After the second step or at the same time as the second step, the first magnetic sheet 51 is heated by the heat source of the flat plate press 42 to make the first magnetic sheet 51 C-staged (part of the sixth step is performed).

(Step 3) In the third step, first, the pressurization of the flat plate press 42 shown in FIG. 8B is released, and then, as shown in FIG. 8C, the first release sheet 41, wiring 2, and second 1 magnetic sheet 51, second release sheet 45, and release buffer sheet 46.

Then, the first release sheet 41 is peeled from the other surface of the first magnetic sheet 51 and the other end edge E4 of the wiring 2 in the thickness direction.

In addition, the second release sheet 45 and the release buffer sheet 46 are peeled from one surface of the first magnetic sheet 51.

(Step 4, Step 5, and the rest of Step 6) As shown in Fig. 9E, the fourth step and the fifth step are performed simultaneously.

As shown in FIG. 9D, in the fourth step and the fifth step, first, the first release sheet 41, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, and the The second magnetic sheet 52 and the second release sheet 45. In addition, the first magnetic sheet 51 and the third magnetic sheet 53 are both B-stage.

Subsequently, as shown in FIG. 9E, the first magnetic sheet 51 and the third magnetic sheet 53 are pressurized by the flat plate press 42.

Thereby, the second magnetic sheet 52 covers one surface of the first magnetic sheet 51 in the thickness direction.

The third magnetic sheet 53 is arranged on the other surface of the first magnetic sheet 51 in the thickness direction so as to cover the other end edge E4 in the thickness direction of the wiring 2. At this time, the movement of the other surface of the relatively hard first magnetic sheet 51 in the C stage is suppressed, and the other end E4 in the thickness direction of the wiring 2 is suppressed from sinking into the opposing portion 28 of the third magnetic sheet 53 . That is, one surface of the third magnetic sheet 53 can be maintained flat.

After that, the second magnetic sheet 52 and the third magnetic sheet 53 are heated by the heat source of the flat plate press 42, so that the second magnetic sheet 52 and the third magnetic sheet 53 are C-staged (implementation 6 The rest of the steps).

Thereby, the inductor 1 provided with the wiring 2 and the magnetic layer 3 is obtained.

As shown in FIG. 9F, the inductor 1 is taken out from the plate pressing machine 42.

Among the first embodiment and the second embodiment, the first embodiment is preferable. According to the first embodiment, in the sixth step, the B-stage thermosetting components of the first adhesive 91 and the third adhesive 93 are simultaneously C-staged, so that it is compatible with the first adhesive 91 and the third adhesive 93 Compared with the second embodiment where the B-stage thermosetting components are sequentially converted into C-stage, the manufacturing time can be shortened. Therefore, the inductor 1 can be easily manufactured.

<Variations of the second embodiment> In the modified example, the same reference numerals are attached to the same members and steps as in the second embodiment, and detailed descriptions thereof are omitted. In addition, the modified example exhibits the same functions and effects as the second embodiment except for special descriptions. Furthermore, the second embodiment and its modification examples can be appropriately combined.

In the second embodiment, the fourth step, the fifth step, and the rest of the sixth step are simultaneously implemented. However, steps 4 and 5 can be implemented, and then the rest of step 6 can be implemented.

In the second embodiment, the fourth step and the fifth step are simultaneously implemented. However, the fourth step and the fifth step can also be performed in sequence.

In this modified example, as shown in FIGS. 10A to 12H, the first step, the second step, the fourth step, the third step, and the fifth step are sequentially performed. In addition, the sixth step is implemented in batches.

As shown in FIG. 10A, in the first step, the wiring 2 is arranged on one surface of the first release sheet 41 in the thickness direction.

As shown in FIG. 10B, the second step is subsequently implemented, and the first magnetic sheet 51 is C-staged. That is, part of the sixth step is implemented. Specifically, the first release sheet 41, the wiring 2, the first magnetic sheet 51, the second release sheet 45, and the release buffer sheet 46 are sandwiched in this order by the flat plate press 42. Subsequently, the wiring 2 and the first magnetic sheet 51 are heat-pressed by the flat plate press 42 through the first release sheet 41, the second release sheet 45, and the release buffer sheet 46. In addition, the first magnetic sheet 51 is C-staged by the heat source of the plate press 42 (part of the sixth step is performed).

As shown in Fig. 11D, the fourth step is subsequently implemented. Specifically, first, the pressurization of the flat plate press 42 shown in FIG. 10B is released, and then, as shown in FIG. 10C, the first release sheet 41, the wiring 2, and the first magnetic sheet 51 are arranged on In the state of the flat plate press 42, the second release sheet 45 and the release buffer sheet 46 are taken out from the flat press 42.

After that, in the fourth step, the second magnetic sheet 52 and the second release sheet 45 are separately arranged on one side in the thickness direction of the first magnetic sheet 51.

As shown in FIG. 11D, next, the second magnetic sheet 52 is heat-pressed using a flat plate press 42. Thereby, the second magnetic sheet 52 covers one surface of the first magnetic sheet 51.

As shown in FIG. 11F, the third step is then implemented.

In the third step, specifically, first, the pressurization of the plate press 42 shown in FIG. 11D is released, and the first release sheet 41, wiring 2, and first magnetic sheet are taken out from the plate press 42 51. The second magnetic sheet 52 and the second release sheet 45.

In the third step, then, as shown in FIG. 11E, the first release sheet 41 is peeled from the other surface of the first magnetic sheet 51 and the other end edge E4 of the wiring 2 in the thickness direction.

As shown in Figure 12G, the fifth step is then implemented.

As shown in FIG. 11F, in the fifth step, first, specifically, the first release sheet 41, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, and the second magnetic sheet 52 And the second release sheet 45 are arranged on the flat plate press 42.

In the fifth step, as shown in FIG. 12G, the third magnetic sheet 53 is hot-pressed by a flat plate press 42. Thereby, the third magnetic sheet 53 is arranged on the other surface of the first magnetic sheet 51 of the C stage so as to cover the other end edge E4 of the thickness direction of the wiring 2.

After step 5 or at the same time as step 5, perform the rest of step 6. Specifically, the second magnetic sheet 52 and the third magnetic sheet 53 are C-staged by the heat source of the plate press 42 to form the third magnetic sheet 53, the first magnetic sheet 51, and the second magnetic sheet. 2 The magnetic layer 3 of the magnetic sheet 52. Thereby, the inductor 1 provided with the magnetic layer 3 of the wiring 2 and the covering wiring 2 is obtained.

As shown in FIG. 12H, after that, the inductor 1 is taken out from the plate pressing machine 42.

Furthermore, in the above-mentioned modification, simultaneously with the second step of arranging the first magnetic sheet 51 for the wiring 2 shown in FIG. 10B, the first magnetic sheet 51 is C-staged, but the first magnetic sheet 51 is not particularly limited as long as the other surface of the first magnetic sheet 51 is placed before the fifth step (see FIG. 5G) of the third magnetic sheet 53 (refer to FIG. 5G). The fourth step of disposing the second magnetic sheet 52 shown in 11D is carried out together.

In addition, the first magnetic sheet 51 and the second magnetic sheet 52 can be simultaneously C-staged. The second magnetic sheet 52 is arranged on one surface of the first magnetic sheet 51 of the B-stage, and thereafter, the first magnetic sheet 51 and the second magnetic sheet 52 are simultaneously C-staged. In addition, the second magnetic sheet 52 may be C-staged, and then the third magnetic sheet 53 may be arranged on the other surface of the first magnetic sheet 51, and then C-staged.

Furthermore, the third magnetic sheet 53 may be arranged on the other surface of the first magnetic sheet 51, and thereafter, the second magnetic sheet 52 may be arranged on one surface of the first magnetic sheet 51. In this case, the third magnetic sheet 53 and the second magnetic sheet 52 may be simultaneously C-staged, and the third magnetic sheet 53 may be C-staged, and then the second magnetic sheet 52 may be C-staged.

In addition, as shown in FIG. 13A, in the first step, the wiring 2 is arranged on a surface in the thickness direction of the third magnetic sheet 53 (an example of the substrate) of the C stage, instead of being arranged on the first release sheet材41.

Specifically, first, the third magnetic sheet 53 of the C-stage is produced and arranged on one surface of the first release sheet 41 in the thickness direction. The third adhesive 93 in the third magnetic sheet 53 contains a cured product of a B-stage thermosetting component.

Then, the first release sheet 41, the C-stage third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, the second release sheet 45, and the release buffer are clamped by the flat plate press 42 Sheet 46.

As shown in Fig. 13B, the second step is performed. In this second step, the first release sheet 41, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, and the second release sheet 45 are sequentially clamped by the flat plate press 42 And release buffer sheet 46.

Then, the first release sheet 41, the second release sheet 45, and the release buffer sheet 46 are separated from the third magnetic sheet 53, the wiring 2 and the first magnetic sheet 51 by the flat plate press 42 Perform hot pressing. Thereby, the first magnetic sheet 51 is arranged on one surface of the third magnetic sheet 53 in the thickness direction of the C-stage in a manner of covering the superior arc of the circumferential surface of the wiring 2.

Subsequently, in the fourth step, first, the pressurization of the flat plate press 42 shown in FIG. 13B is released, and then, as shown in FIG. 13C, the first release sheet 41, the third magnetic sheet 53, and In a state where the wiring 2 and the first magnetic sheet 51 are arranged in the flat plate press 42, the second release sheet 45 and the release buffer sheet 46 are taken out from the flat plate press 42.

Subsequently, in the subsequent fourth step, the second magnetic sheet 52 and the second release sheet 45 are separately arranged on one side in the thickness direction of the first magnetic sheet 51. The first release sheet 41, the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51, the second magnetic sheet 52, and the second release sheet 45 are clamped by the flat plate press 42.

Thereafter, as shown in FIG. 14D, the second magnetic sheet 52 is pressurized by the flat press 42.

After that, the second magnetic sheet 52 and the first magnetic sheet 51 are C-staged. Thereby, the magnetic layer 3 including the third magnetic sheet 53, the first magnetic sheet 51, and the second magnetic sheet 52 is formed.

Thereafter, as shown in FIG. 14E, inductor 1 is obtained.

In the above modification, the first magnetic sheet 51 and the second magnetic sheet 52 are C-staged at the same time, but for example, the second magnetic sheet 52 may be C-staged after the first magnetic sheet 51 is C-staged. Be C-staged.

＜Other variation examples＞ In this modified example, the same reference numerals are attached to the same members and steps as in the first and second embodiments, and detailed descriptions thereof are omitted. In addition, unless otherwise specified, the modified example can exhibit the same effects as the first and second embodiments. Furthermore, the first and second embodiments and their modified examples can be appropriately combined.

As shown in FIG. 15A, in the first step, the wiring 2 can be arranged on one surface of the first release sheet 41 through the pressure sensitive adhesive layer 61.

The pressure-sensitive adhesive layer 61 extends in the second direction and is formed in a thin sheet shape. The ratio of the length of the pressure-sensitive adhesive layer 61 in the first direction to the radius R of the wiring 2 is, for example, 0.5 or less and 0.25 or less.

As shown in FIG. 15B, in the second step, the first magnetic sheet 51 covers the superior arc of the circumferential surface of the wiring 2 by filling the pressure-sensitive adhesive layer 61 on both sides in the first direction.

As shown in FIG. 15C, the inductor 1 may not have the pressure-sensitive adhesive layer 61 remaining between the third magnetic sheet 53 and the other end edge E4 in the thickness direction, or, although it is not shown in the figure, it may be removed after the second step.压接层61。 Pressure bonding layer 61.

Moreover, as shown in FIG. 16A, in the first step, the wiring 2 may be arranged on one side of the first release sheet 41 with a gap 62 separated therefrom. For example, by interposing spacers (not shown) between both ends of the wiring 2 in the second direction and the first release sheet 41, both sides in the second direction are stretched and the wiring 2 is secured A gap 62 between the other end edge E4 in the thickness direction and one surface of the wiring 2.

As shown in FIG. 16B, in the hot pressing in the second step, the first magnetic sheet 51 is filled in the gap 62 to cover the entire circumference of the wiring 2.

Thereafter, as shown in FIG. 16C, one surface of the first magnetic sheet 51 is covered with the second magnetic sheet 52.

After that, for example, heating and pressure are simultaneously applied to make the first adhesive 91 of the first magnetic sheet 51 and the second adhesive 92 of the second magnetic sheet 52 C-stage.

Thereby, the magnetic layer 3 including the first magnetic sheet 51 and the second magnetic sheet 52 is formed.

In this method, the third magnetic sheet 53 may not be arranged, and the other end edge E4 of the wiring 2 in the thickness direction may be covered with the magnetic layer 3. Therefore, the number of steps can be reduced.

Furthermore, as shown by the imaginary line in FIG. 16C, the third magnetic sheet 53 may be further arranged on the other surface of the second magnetic sheet 52 as needed.

Alternatively, as shown in FIG. 2A, in the first step, the wiring 2 is brought into contact with one of the surfaces of the first release sheet 41, as shown by the imaginary line arrow in FIG. 6B, and then the addition in the second step is adjusted The pressing conditions are such that the first magnetic composition forming the first magnetic sheet 51 is immersed in the other side of the wiring 2 in the thickness direction so as to cover the other end edge E4 of the wiring 2 in the thickness direction. In this modified example, the aforementioned spacer is not required, and therefore, the inductor 1 can be easily manufactured.

In the first embodiment and the second embodiment, the first anisotropic magnetic particles 81 are cited as an example of the first magnetic particles. However, for example, the first magnetic particles may not have anisotropy and, for example, have isotropy. . Examples of the shape of such first isotropic magnetic particles include a substantially spherical shape. Examples of the first isotropic magnetic particles having a substantially spherical shape include iron particles having a substantially spherical shape. The average particle diameter of the first isotropic magnetic particles is, for example, 0.1 μm or more, preferably 0.5 μm or more, and for example, 200 μm or less, preferably 150 μm or less.

In addition, as shown in FIG. 2A of the first embodiment, FIG. 4A of its modification, and FIG. 8A of the second embodiment and FIG. 10A and FIG. 13A of its modification, the first anisotropic magnetic particles 81 are in the first magnetic The sheet 51 is aligned in the surface direction, but it is not limited to this, and may not be aligned in the surface direction in the first magnetic sheet 51.

In the first embodiment and the second embodiment, the third anisotropic magnetic particle 83 is cited as an example of the third magnetic particle. For example, the third magnetic particle may not have anisotropy, but may have isotropy, for example. As the shape of such third isotropic magnetic particles, for example, a substantially spherical shape can be cited. As the third isotropic magnetic particles having a substantially spherical shape, for example, iron particles having a substantially spherical shape can be cited. The average particle diameter of the third isotropic magnetic particles is, for example, 0.1 μm or more, preferably 0.5 μm or more, and for example, 200 μm or less, preferably 150 μm or less.

In addition, as shown in Fig. 3D of the first embodiment, Fig. 5F of the modification, Fig. 9D of the second embodiment, Fig. 11F and Fig. 13C of the modification, the third anisotropic magnetic particle 83 is in the third magnetic The sheet 53 is aligned in the surface direction, but it is not limited to this, and may not be aligned in the surface direction in the third magnetic sheet 53.

As shown in FIGS. 1B and 7B, in the first embodiment and the second embodiment, the anisotropic magnetic particles 8 are aligned along the circumferential direction of the wiring 2 at least in the first region 11, but it is not limited to this. It may not be aligned along the circumferential direction of the wiring 2.

In addition, the ratio (filling rate) of the magnetic particles (the first magnetic particle, the second anisotropic magnetic particle 82, and the third magnetic particle) in the magnetic layer 3 is not limited to the above. For example, as the distance from the wiring 2 increases, it may increase or decrease. Go low. In order to manufacture the inductor 1 in which the ratio of the magnetic particles in the magnetic layer 3 increases as the distance from the wiring 2 becomes higher, for example, the ratio of the second anisotropic magnetic particles 82 in the second magnetic sheet 52 is set to be higher than The existence ratio of magnetic particles in the first magnetic sheet 51.

Furthermore, as described above, in the variation example where the filling rate of the magnetic particles in the magnetic layer 3 becomes higher or lower as the distance from the wiring 2 is increased, the magnetic layer 3 may be a plurality of layers. In this case, one of the plurality of magnetic sheets can be used to cover the outer peripheral surface of the wiring 2 to pressurize the wiring 2, and then use the remaining magnetic sheets to pressurize it. Or alternatively, the wiring 2 may be pressurized with a plurality of magnetic sheets at a time (unified). For example, the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53 of one embodiment can be used to pressurize the wiring 2 at a time. Specifically, the first step shown in FIG. 13A, the second step shown in FIG. 13B, and the fourth step shown in FIG. 13C can be performed simultaneously. [Example]

Examples and comparative examples are shown below to explain the present invention more specifically. In addition, the present invention is not limited by any Examples and Comparative Examples. In addition, specific numerical values such as blending ratios (content ratios), physical property values, and parameters used in the following descriptions can be substituted for the blending ratios (content ratios) corresponding to them described in the above-mentioned "modes for implementing the invention" The upper limit (defined as the value of "below" or "not reached") or lower limit (defined as the value of "above" or "exceeding") corresponding to the corresponding records of physical property values and parameters.

Example 1 ＜Production example of inductor based on the first embodiment＞ In Example 1, the inductor 1 was manufactured based on the first embodiment. Specifically, as shown in FIGS. 2A to 3F, the first step, the second step, and the third step are sequentially performed, and then the fourth step, the fifth step, and the sixth step are simultaneously performed.

(Step 1) The wiring 2 and the first release sheet 41 are prepared.

Specifically, wiring 2 with a radius R of 110 μm is prepared. The radius R1 of the wire 6 is 100 μm, and the thickness R2 of the insulating layer 7 is 10 μm.

Separately, a first release sheet 41 containing PET with a thickness of 50 μm was prepared.

Then, as shown in FIG. 2A, the wiring 2 is arranged on one surface of the first release sheet 41 in the thickness direction.

(Step 2) The first magnetic sheet 51, the second release sheet 45, and the release buffer sheet 46 are prepared.

Specifically, a first magnetic sheet 51 composed of a laminated sheet of the inner sheet 54 and the outer sheet 55 is prepared as a B-stage sheet, and the ratio of the anisotropic magnetic particles 8 of the inner sheet 54 is 50 by volume %, the ratio of the anisotropic magnetic particles 8 of the outer sheet 55 is 60% by volume. The formulations of the inner sheet 54 and the outer sheet 55 are as described in Table 1.

In addition, as the second release sheet 45, a release film (manufactured by Mitsui Chemicals Tohcello Co., Ltd.) containing TPX (registered trademark) is prepared.

In addition, a release cushion sheet 46 obtained by laminating two release films OT-A110 (manufactured by Sekisui Chemical Industry Co., Ltd.) is prepared.

The thickness of the release buffer sheet 46 (total thickness of the release film OT-A110) is 110 μm, with a first layer 47 with a thickness of 15 μm, a second layer 48 with a thickness T2 of 80 μm, and a thickness of 15 μm The third layer 49. The tensile storage modulus E'of the first layer 47 and the third layer 49 at 110°C is 190 MPa, and the material contains polybutylene terephthalate as the main component. The tensile storage modulus E'of the second layer 48 at 110°C is 5.6 MPa, and its material contains ethylene-methyl methacrylate copolymer as the main component.

Subsequently, the first release sheet 41, the wiring 2, the first magnetic sheet 51, the second release sheet 45, and the release buffer sheet 46 are clamped in this order by the flat plate press 42.

As shown in FIG. 2B, next, the wiring 2 and the first magnetic sheet 51 are hot-pressed by a flat plate press 42 under a pressing pressure of 2 MPa, a pressing condition of 110° C. and 60 seconds.

FIG. 17A shows an SEM photograph of the cross section of the wiring 2 and the first magnetic sheet 51 after the second step.

(Step 3) In the third step, first, the pressurization of the flat plate press 42 shown in FIG. 2B is released, and then, as shown in FIG. 2C, the first release sheet 41, wiring 2, and second 1 magnetic sheet 51, second release sheet 45, and release buffer sheet 46. Then, the first release sheet 41 is peeled from the other surface of the first magnetic sheet 51 and the other end edge E4 of the wiring 2 in the thickness direction. In addition, the second release sheet 45 and the release buffer sheet 46 are peeled from one surface of the first magnetic sheet 51.

(Step 4, Step 5, and Step 6) The second magnetic sheet 52 and the third magnetic sheet 53 are prepared.

Specifically, prepare 5 sheets with the same formula as the outer sheet 55 in the first magnetic sheet 51 (the ratio of the anisotropic magnetic particles 8 is 60% by volume), and prepare laminated sheets made of them The second magnetic sheet 52 constituted as a B-stage sheet.

In addition, prepare 4 sheets of the same formulation as the outer sheet 55 in the first magnetic sheet 51 (the ratio of the anisotropic magnetic particles 8 is 60% by volume), and 1 sheet and the first magnetic sheet 51 The inner sheet 54 has the same formula (the ratio of anisotropic magnetic particles 8 is 50% by volume), which is laminated, and the third magnetic sheet 53 composed of the laminated sheets of the same is prepared as a B-stage sheet .

As shown in FIG. 3D, subsequently, between the first plate 43 and the second plate 44, the first release sheet 41, the third magnetic sheet 53, the wiring 2, and the first magnetic sheet are sequentially arranged toward the thickness direction side. The sheet 51, the second magnetic sheet 52, and the second release sheet 45 (PET film).

As shown in FIG. 3E, then, under the pressurizing conditions of 2 MPa, 170° C. and 900 seconds, the flat plate press 42 pairs the third magnetic sheet 53, the wiring 2, the first magnetic sheet 51 and The second magnetic sheet 52 is hot-pressed. Thereby, the thermosetting component C in the first adhesive 91, the second adhesive 92, and the third adhesive 93 is staged.

Thereby, the circumferential surface of the wiring 2 is covered by the magnetic layer 3 including the first magnetic sheet 51, the second magnetic sheet 52, and the third magnetic sheet 53 of the C-stage, and the manufacturing shown in FIGS. 1A to 1B Inductor 1.

After that, as shown in FIG. 3F, the inductor 1 is taken out from the plate pressing machine 42.

The SEM photograph of the cross section of the inductor 1 is shown in FIG. 17B.

Example 2 <Production example of inductor based on the variation of the first embodiment> In Example 2, the inductor 1 was manufactured based on the modification of the first embodiment shown in FIGS. 4A to 6H. Specifically, except that the first step, the second step, the fourth step, the third step, the fifth step, and the sixth step are sequentially performed, the processing is performed in the same manner as in the first embodiment.

The inductor 1 is shown in FIGS. 7A to 7B, and the SEM photograph of its cross-section is shown in FIG. 18.

Example 3 ~ Example 5 According to Table 1, except for changing the formula of the first magnetic sheet 51, the treatment was performed in the same manner as in Example 1, and the inductor 1 was manufactured.

Comparative example 1 On one side in the thickness direction of the first plate 43, a first release sheet 41 containing PET with a thickness of 50 μm, a third magnetic sheet 53 of the C-stage, the first adhesive layer of the B-stage, and the examples are sequentially arranged 1 The same wiring 2, the second adhesive layer of the B stage, the second magnetic sheet 52 of the C stage, the second release sheet 45 containing TPX, the two release films OT-A110 (manufactured by Sekisui Chemical Industry Co., Ltd.) ) The release cushion sheet 46 obtained by the lamination is sandwiched between the first plate 43 and the second plate 44 with a layered body composed of these.

In addition, both the first adhesive layer and the second adhesive layer are B-stage sheets that do not include the anisotropic magnetic particles 8 but include thermosetting resin. The thickness of the first adhesive layer and the second adhesive layer are 2 μm, respectively.

The formulations of the second magnetic sheet 52 of the C-stage and the third magnetic sheet 53 of the C-stage are as described in Table 1, and both are fully hardened hardened bodies.

Subsequently, the laminated body was hot-pressed by the flat-plate press 42 under a pressing pressure of 2 MPa at 170° C. and 900 seconds to manufacture the inductor 1.

The SEM photograph of the cross section of the inductor 1 of Comparative Example 1 is shown in FIG. 19.

As can be seen from FIG. 19, voids are formed between the second circular arc surface 24 of the wiring 2 and the end edges E2 and E3 in the first direction and the first magnetic sheet 51 (magnetic layer 3).

Comparative example 2 On one side of the first plate 43 in the thickness direction, a first release sheet 41 containing PET with a thickness of 50 μm, a third magnetic sheet 53 of C-stage, a first pressure-sensitive adhesive layer, and Example 1 are sequentially arranged The same wiring 2, the second pressure-sensitive adhesive layer, the second magnetic sheet 52 of the C-stage, the second release sheet 45 containing TPX, the two release films OT-A110 (manufactured by Sekisui Chemical Industry Co., Ltd.) are laminated The obtained release buffer sheet 46 is sandwiched between the first plate 43 and the second plate 44 with a laminate including it.

Furthermore, both the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer do not include anisotropic magnetic particles 8 but a pressure-sensitive adhesive tape (adhesive tape) containing an acrylic pressure-sensitive adhesive (adhesive). The thickness of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer are 5 μm, respectively.

The formulations of the second magnetic sheet 52 of the C-stage and the third magnetic sheet 53 of the C-stage are as described in Table 1, and both are fully hardened hardened bodies.

Subsequently, the laminated body was hot-pressed by the plate press 42 under the press conditions of a press pressure of 2 MPa, 110° C. and 60 seconds to manufacture the inductor 1.

A void is formed between the second circular arc surface 24 of the wiring 2 and the first direction end edges E2 and E3 and the first magnetic sheet 51 (magnetic layer 3).

＜Filling rate＞ According to the binarization of the cross-sectional view of the SEM photograph, the filling rate of the anisotropic magnetic particles 8 in the peripheral region 4 of the inductor 1 is calculated. Specifically, in the SEM photograph, white is identified as the anisotropic magnetic particle 8, and black is identified as the binder 9. Then, the anisotropic magnetic particle is obtained from the ratio of the cross-sectional area of the white in the first region 11 8 fill rate (existence ratio).

The results are shown in Table 1.

＜Inductance＞ The two ends of the wire 6 in the transmission direction are exposed from the insulating layer 7 and the magnetic layer 3 to form two exposed parts, and the exposed parts are connected to an impedance analyzer (manufactured by Agilent: 4294A), and the inductance is calculated based on the following reference Evaluate the inductance of inductor 1. ◎: The inductance is 110 H or more ○: The inductance is above 90 H, but less than 110 H △: The inductance is above 60 H, but less than 90 H ×: The inductance is less than 60 H The results are shown in Table 1.

[Table 1] Table 1 Magnetic composition Example 1 / Example 2 Example 3 Example 4 Example 5 Comparative example 1 Comparative example 2 The first magnetic sheet The first magnetic sheet The first magnetic sheet The first magnetic sheet 2nd magnetic sheet / 3rd magnetic sheet 2nd magnetic sheet / 3rd magnetic sheet 2-layer sheet of stage B 2-layer sheet of stage B 2-layer sheet of stage B 2-layer sheet of stage B B-stage adhesive sheet and C-stage magnetic sheet Pressure sensitive adhesive tape and C-stage magnetic sheet Inner sheet Outer sheet Single sheet Single sheet Single sheet Inner sheet * ¹ Outer sheet* ² Inner sheet * ³ Outer sheet* ² volume% volume% volume% volume% volume% volume% volume% volume% volume% Magnetic particles Flat soft magnetic particles Fe-Si-Al alloy (average particle size 40 μm) 50 60 50 40 30 0 60 0 60 Thermoplastic component Acrylate copolymer containing carboxyl group Tessan resin SG-70L manufactured by Nagase ChemteX 23.7 18.8 23.7 28.5 33.5 48.6 18.8 - 18.8 Thermosetting component (epoxy resin composition) Cresol novolac epoxy resin (main agent) KI-3000-4 epoxy equivalent of 199 g/eq manufactured by Nippon Steel & Sumikin Chemical Company 12.2 9.7 12.2 14.7 17.2 25.1 9.7 9.7 Phenolic resin (hardener) MEH-7851SS manufactured by Minghe Chemical Company 12.4 9.8 12.4 15.0 17.6 25.5 9.8 9.8 Imidazole compound (hardening accelerator) 2PHZ-PW manufactured by Shikoku Chemical Industry Co., Ltd. 0.4 0.3 0.4 0.5 0.6 0.8 0.3 0.3 The filling rate of anisotropic magnetic particles in the surrounding area (vol%) 57 55 53 58 34 18 Whether there are pores no no no no Have Have Evaluation (inductance) ◎ ◎ 〇 〇 △ X *1: B-stage adhesive sheet *2: C-stage magnetic sheet *3: pressure sensitive adhesive tape

In addition, the above-mentioned invention is provided as an exemplary embodiment of this invention, but this is only an illustration, and should not be interpreted restrictively. Variations of the present invention clear to those skilled in the art are included in the scope of the following patent applications. [Industrial availability]

The inductor is mounted on, for example, electronic equipment.

1: Inductor 2: Wiring 3: Magnetic layer 4: Surrounding area 5: Outer area 6: Wire 7: Insulation layer 8: Anisotropic magnetic particles 9: Adhesive 11: Zone 1 12: Zone 2 13: Zone 3 14: Zone 4 15: Zone 5 16: Zone 6 17: The first particle 18: The second particle 19: The third particle 20: Intersection (top) 21: 1st intersection (1st top) 22: 2nd intersection (2nd top) 23: The first semicircular arc surface 24: The second semicircular arc surface 25: Uplift 26: flat part 27: Top 2 28: Opposite Department 29: 2nd flat part 34: Overlap 35: non-overlapping part 38: Squeezed part 41: The first release sheet 42: Flat press 43: first board 44: second board 45: The second release sheet 46: Release buffer sheet 47: Level 1 48: Layer 2 49: Layer 3 51: The first magnetic sheet 52: The second magnetic sheet 53: The third magnetic sheet 54: Inside sheet 55: Outer sheet 61: Pressure sensitive adhesive layer 62: gap 81: The first anisotropic magnetic particle (an example of the first magnetic particle) 82: The second anisotropic magnetic particle (an example of the second magnetic particle) 83: The third anisotropic magnetic particle (an example of the third magnetic particle) 91: The first adhesive 92: The second adhesive 93: third adhesive A1: The first imaginary arc A2: The second imaginary arc C: The center of wiring C1: Center angle (zone 3) C2: Center angle (zone 4) C3: Center of the first imaginary arc C4: The center of the second imaginary arc E1: End edge E2: End edge E3: End edge E4: End edge E5: End 1 E6: end 2 E7: End 3 E8: End 4 L1: The first imaginary line L2: The second imaginary line L3: 3rd imaginary line R1: radius R2: thickness α1: The angle of the center angle (the third area) α2: The angle of the center angle (the 4th area)

1A to 1B are cross-sectional views of an inductor obtained according to the first embodiment of the present invention, FIG. 1A is a cross-sectional view of the cross-section shaded, and FIG. 1B is a cross-sectional view showing the alignment of anisotropic magnetic particles in the magnetic layer. 2A to 2C are diagrams illustrating the steps of the method of manufacturing the inductor of the first embodiment. FIG. 2A shows the first step of arranging the wiring on the first release sheet, and FIG. 2B shows the first step of covering the wiring with the first magnetic sheet. The second step, FIG. 2C shows the third step of removing the first release sheet. Figures 3D to 3F are diagrams illustrating steps of the method of manufacturing the inductor of the first embodiment following Figure 2C. Figure 3D shows the steps of arranging the second magnetic sheet and the third magnetic sheet, and Figure 3E shows the use of the second magnetic sheet. The fourth step of covering one surface of the first magnetic sheet with a magnetic sheet, and the fifth step of covering the other surface of the first magnetic sheet of stage B with a third magnetic sheet. Figure 3F shows the step of taking out the inductor . 4A ~ 4C is a step diagram illustrating the manufacturing method of a modification of the first embodiment, FIG. 4A shows the first step of disposing the wiring on the first release sheet, and FIG. 4B shows the first step of covering the wiring with the first magnetic sheet The second step, FIG. 4C shows the step of arranging the second magnetic sheet. Figures 5D to 5F are step diagrams illustrating the manufacturing method of the modification of the first embodiment following Figure 4C. Figure 5D shows the fourth step of covering one surface of the first magnetic sheet with the second magnetic sheet. 5E shows the third step of removing the first release sheet, and FIG. 5F shows the step of arranging the third magnetic sheet. FIGS. 6G to 6H are steps diagrams illustrating the manufacturing method of the modification of the first embodiment following FIG. 5F. FIG. 6G shows the third magnetic sheet covering the other surface of the first magnetic sheet of stage B. 5 steps, Figure 6H shows the steps to take out the inductor. 7A to 7B are cross-sectional views of an inductor obtained according to the second embodiment of the present invention, FIG. 7A is a cross-sectional view of the cross-section shaded, and FIG. 7B is a cross-sectional view of the alignment of anisotropic magnetic particles in the magnetic layer. 8A to 8C are diagrams illustrating the steps of the method of manufacturing the inductor of the second embodiment. FIG. 8A shows the first step of arranging the wiring on the first release sheet, and FIG. 8B shows the first step of covering the wiring with the first magnetic sheet. The second step, Fig. 8C shows the third step of removing the first release sheet. 9D to 9F are subsequent to FIG. 8C, illustrating the steps of the method of manufacturing the inductor of the second embodiment, FIG. 9D shows the steps of disposing the second magnetic sheet and the third magnetic sheet, and FIG. 9E shows the use of the second magnetic sheet. The fourth step of covering one surface of the first magnetic sheet with a magnetic sheet, and the fifth step of covering the other surface of the first magnetic sheet of stage C with a third magnetic sheet. Fig. 9F shows the step of taking out the inductor . 10A to 10C are diagrams illustrating the steps of the manufacturing method of the modification of the second embodiment. FIG. 10A shows the first step of arranging wiring on the first release sheet, and FIG. 10B shows the first step of covering the wiring with the first magnetic sheet. The second step, Fig. 10C shows the step of arranging the second magnetic sheet. 11D to 11F are diagrams illustrating steps of the manufacturing method of a modification of the second embodiment following FIG. 10C. FIG. 11D shows the fourth step of covering one surface of the first magnetic sheet with the second magnetic sheet. 11E shows the third step of removing the first release sheet, and FIG. 11F shows the step of arranging the third magnetic sheet. Figures 12G to 12H are step diagrams illustrating the manufacturing method of the modification of the second embodiment following Figure 11F. Figure 12G shows the third magnetic sheet covering the other surface of the first magnetic sheet of the C stage 5 steps, Figure 12H shows the steps to take out the inductor. Figures 13A to 13C are process diagrams illustrating the manufacturing method of another modification of the second embodiment. Figure 13A shows the third magnetic sheet arrangement step in the C stage, and Figure 13B shows the coating with the first magnetic sheet The process of wiring and one surface of the third magnetic sheet. FIG. 13C shows the process of arranging the second magnetic sheet. 14D-14E is a step diagram illustrating the manufacturing method of another modification of the second embodiment following FIG. 13C. FIG. 14D shows the step of covering the first magnetic sheet with the second magnetic sheet, and FIG. 14E shows the removal Inductor steps. 15A to 15C are cross-sectional views of variations of the manufacturing method of the inductor. FIG. 15A shows the step of arranging wiring on one surface of the first release sheet through the pressure sensitive adhesive layer, and FIG. 15B shows the use of the first magnetic sheet Fig. 15C shows the step of obtaining an inductor in the area of the circumferential surface of the material-covered wiring that exceeds 180° when viewed in cross-section and the surface of the first magnetic sheet. 16A to 16C are cross-sectional views of a variation of the manufacturing method of the inductor. FIG. 16A shows the step of arranging the wiring and the first release sheet at intervals, and FIG. 16B shows the circumference of the wiring covered with the first magnetic sheet Fig. 16C shows the step of obtaining an inductor. 17A-17B are the image processing diagrams of the SEM photos of Example 1, FIG. 17A is the SEM photos after the second step, and FIG. 17B is the SEM photos of the inductor. 18 is an image processing diagram of an SEM photograph of the inductor of Example 2. FIG. 19 is an image processing diagram of the SEM photograph of the inductor of Comparative Example 1. FIG.

2: Wiring

5: Outer area

6: Wire

7: Insulation layer

8: Anisotropic magnetic particles

9: Adhesive

12: Zone 2

13: Zone 3

15: Zone 5

16: Zone 6

20: Intersection (top)

21: 1st intersection (1st top)

23: The first semicircular arc surface

24: The second semicircular arc surface

25: Uplift

26: flat part

27: Top 2

34: Overlap

35: non-overlapping part

38: Squeezed part

41: The first release sheet

42: Flat press

43: first board

44: second board

45: The second release sheet

46: Release buffer sheet

47: Level 1

48: Layer 2

49: Layer 3

51: The first magnetic sheet

54: Inside sheet

55: Outer sheet

81: The first anisotropic magnetic particle (an example of the first magnetic particle)

91: The first adhesive

E1: End edge

E2: End edge

E3: End edge

E4: End edge

Claims (8)

A method for manufacturing an inductor, which is characterized by having: The first step is to arrange wiring on a surface of the substrate in the thickness direction. The wiring is provided with wires and an insulating layer covering the wires, and has a substantially circular shape in cross-section; The second step is to arrange the first magnetic sheet on one surface of the substrate in the thickness direction so as to cover an area exceeding 180° in the circumferential surface of the wiring, and the first magnetic sheet includes the first Magnetic particles, and a first binder for dispersing the first magnetic particles; and The fourth step is to coat one surface of the first magnetic sheet in the thickness direction with a second magnetic sheet, and the second magnetic sheet contains a second magnetic material including second anisotropic magnetic particles aligned in the surface direction. Particles, and a second adhesive for dispersing the second magnetic particles, and the first magnetic sheet covers the area of the circumferential surface and the one surface of the substrate. The method for manufacturing an inductor according to claim 1, wherein the first magnetic particles include first anisotropic magnetic particles, and the first anisotropic magnetic particles are aligned in a plane direction in the first magnetic sheet. Such as the manufacturing method of the inductor of claim 1 or 2, where The above-mentioned substrate is a release sheet, The manufacturing method of the inductor further includes: The third step is to remove the above-mentioned substrate; and The fifth step is to arrange the third magnetic sheet on the other surface of the first magnetic sheet in the thickness direction so as to cover the circumferential surface exposed from the other surface of the first magnetic sheet in the thickness direction. The third magnetic sheet includes third magnetic particles and a third binder for dispersing the third magnetic particles. The method for manufacturing an inductor according to claim 3, wherein the third magnetic particles include third anisotropic magnetic particles, and the third anisotropic magnetic particles are aligned in a plane direction in the third magnetic sheet. For example, the manufacturing method of the inductor of claim 3, which sequentially implements the first step, the second step, and the third step, and then the fourth step and the fifth step are simultaneously performed. The method for manufacturing an inductor according to claim 3, wherein the first adhesive in the second step and the third adhesive in the fifth step contain a B-stage thermosetting component, The manufacturing method of the inductor further includes a sixth step that further converts the B-stage thermosetting components of the first adhesive and the third adhesive into C-stages at the same time. The method for manufacturing an inductor according to claim 1 or 2, wherein the substrate is a third magnetic sheet, which includes third magnetic particles and a third adhesive for dispersing the third magnetic particles, The third adhesive contains a cured product of a thermosetting component. The method for manufacturing an inductor according to claim 7, wherein the third magnet particles include third anisotropic magnet particles, and the third anisotropic magnet particles are aligned in a plane direction in the third magnet sheet.

Images