JP6093941B2 - Compact core, electrical / electronic components and electrical / electronic equipment - Google Patents

Description

  The present invention relates to a dust core using soft magnetic powder, an electric / electronic component including the dust core, and an electric / electronic device on which the electric / electronic component is mounted.

  The dust core used as a component of electrical and electronic parts such as inductance elements, reactors, transformers and choke coils is compacted with a number of soft magnetic powders together with resin, etc., and the resulting compact is heat treated. Can be obtained. Patent Document 1 below discloses an example of a dust core.

JP 2012-212853 A

  The dust core obtained by the above manufacturing method is a composite of soft magnetic powder and a resin-based material, and the soft magnetic powder in the dust core is usually up to about 300 ° C. even in the air. If present, it is thermally stable. However, when the dust core is heated to such a temperature, the thermal deterioration of the resin-based material becomes obvious, and the magnetic properties of the dust core change.

As one of the scales for evaluating the thermal stability of such a dust core, a heating test that is allowed to stand in an atmosphere at 250 ° C. for 1000 hours (in this specification, a “heating test”, This means the heating test.) The rate of change of core loss when the powder core is performed can be mentioned. As used herein, the core loss Pc ₀ (unit: kW / ^{m 3)} of the dust core was measured before the heating test of the dust cores were measured and after the heating test core loss Pc ₁ (unit kW / ^{m 3)} Using the fact that the core loss change rate ΔPc (unit:%) defined by the following formula is small is referred to as “the powder core is excellent in heat resistance”.
ΔPc = (Pc ₁ −Pc ₀ ) / Pc ₀ × 100

  An object of the present invention is to provide a dust core excellent in heat resistance, an electric / electronic component including the dust core, and an electric / electronic device on which the electric / electronic component is mounted.

  As a result of investigations by the present inventors in order to solve the above problems, it has been found that a dust core in which a peak based on specific ions is measured when measured by TOF-SIMS is excellent in heat resistance.

The present invention completed based on the above knowledge, as one aspect, is a powder core comprising soft magnetic powder and an insulating resin-based material, and the resin providing the resin-based material contains an acrylic resin. When the powder core is measured by TOF-SIMS under the following conditions, the first ion consisting of at least one of the ions represented by C _n H _2n-1 O ₂ ⁻ (n = 11 to 20) A dust core characterized in that a peak based on it is measured is provided.
Irradiated ions: Bi ³⁺
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Irradiation mode: Bunching mode

C ₃ H ₃ O ₂ to be measured when measuring the dust core by TOF-SIMS under the above conditions ^- to the intensity of the peak based on, first the ratio of the intensity of the peak based on the first ion 1 The intensity ratio is preferably 0.03 or more.

  When the dust core is measured by TOF-SIMS under the above conditions, the maximum value of the peak based on the ions is the mass / u where the peak based on the first ion is the maximum value, and the mass / u At least one peak based on a second ion that is an ion other than the first ion is measured, and the intensity of the peak of the second ion It is preferable that the second intensity ratio, which is the ratio of the peak intensity of the first ions to the sum of the above, is 0.1 or more.

Another aspect of the present invention is a dust core comprising soft magnetic powder and an insulating resin material, wherein the resin providing the resin material contains an acrylic resin, and the dust core Is measured by TOF-SIMS under the following conditions, a peak based on the third ion represented by C ₅ H ₇ O ₃ ^— is measured.
Irradiated ions: Bi ³⁺
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Irradiation mode: Bunching mode

C ₃ H ₃ O ₂ that will be measured when measuring the dust core by TOF-SIMS under the above conditions ^- to the intensity of the peak based on the third is the ratio of the intensity of the peak based on the third ion The intensity ratio is preferably 0.05 or more.

Another aspect of the present invention is a dust core comprising soft magnetic powder and an insulating resin material, wherein the resin providing the resin material contains an acrylic resin, and the dust core Is measured by TOF-SIMS under the conditions below , a peak based on the fourth ion represented by C ₇ H ₁₁ O ₂ ^— is measured.

C ₃ H ₃ O ₂ to be measured when measuring the dust core by TOF-SIMS under the above conditions ^- to the intensity of the peak based on the ratio of the intensity of the peak based on the fourth ion fourth The intensity ratio is preferably 0.02 or more.

The powder core according to the present invention may further include at least one of the following characteristics.
The ratio of the peak intensity based on C ₂ HO ⁻ to the peak intensity based on C ₂ H ₃ O ₂ ⁻ measured when the dust core is measured by TOF-SIMS under the conditions described above. The fifth intensity ratio is 10 or less.
-The powder core contains P (phosphorus). When the powder core contains P, at least one of the first ion, the third ion, and the fourth ion may tend to be easily measured.
The soft magnetic powder has an amorphous part.
The soft magnetic powder is an Fe-based amorphous alloy, Ni is 0 atomic% to 10 atomic%, Sn is 0 atomic% to 3 atomic%, Cr is 0 atomic% to 6 atomic%, P contains 3.0 atomic% or more and 11 atomic% or less, C contains 1.0 atomic% or more and 10 atomic% or less, B contains 0 atomic% or more and 9 atomic% or less, and Si contains 0 atomic% or more and 6 atomic% or less. . When the Fe-based amorphous alloy contains P, at least one of the first ion, the third ion, and the fourth ion may tend to be easily measured.
This invention provides the manufacturing method of said powder core as another one aspect | mode. In the said manufacturing method , the said powder core is obtained by press-molding the composition containing the said soft-magnetic powder and resin, obtaining a molded object, and heating the obtained said molded object. The heating of the molded body preferably includes heating in an oxidizing atmosphere and subsequent heating in a non-oxidizing atmosphere. The composition may contain an inorganic component, and the inorganic component preferably contains P. When the inorganic component contains P, at least one of the first ion, the third ion, and the fourth ion may tend to be easily measured.

  In another aspect, the present invention provides an electric / electronic component including the dust core, the coil, and a connection terminal connected to each end of the coil, and at least a part of the dust core. Provides an electrical / electronic component arranged to be located in an induced magnetic field generated by the current when a current is passed through the coil via the connection terminal.

  As still another aspect of the present invention, there is provided an electric / electronic device in which the electric / electronic component is mounted, wherein the electric / electronic component is connected to a substrate by the connection terminal. Provide equipment.

  The dust core according to the above invention is excellent in heat resistance. Further, according to the present invention, there are provided an electric / electronic component having such a dust core and an electric / electronic device on which the electric / electronic component is mounted.

It is a perspective view which shows notionally the shape of the powder core which concerns on one Embodiment of this invention. It is a figure which shows the cross-sectional observation result of the powder core which concerns on one Embodiment of this invention. The figure which shows a part of spectrum (mass / u is 185 vicinity, 199 vicinity, and 213 vicinity) obtained by measuring by TOF-SIMS about each of the powder core manufactured by Example 1 and Comparative Examples 1-3. It is. It is a perspective view which shows notionally the shape of the toroidal core which is an electric / electronic component provided with the powder core which concerns on one Embodiment of this invention. It is a perspective view which shows a partial see-through | perspective view and shows the whole structure of the inductance element which is an electric / electronic component provided with the powder core which concerns on another one Embodiment of this invention. It is a partial front view which shows the state which mounted the inductance element shown in FIG. 5 on the mounting board | substrate. It is a figure which shows another part (mass / u is 115 vicinity and 127 vicinity) obtained by measuring by TOF-SIMS about each of the compacting core manufactured by Example 1 and Comparative Examples 1-3. is there.

Hereinafter, embodiments of the present invention will be described in detail.
1. 1. The dust core 1 according to one embodiment of the present invention shown in FIG. 1 is ring-shaped in appearance, and is based on soft magnetic powder M and an acrylic resin as shown in FIG. An insulating resin material R containing components is provided.

(1) Ions measured by TOF-SIMS The powder core 1 according to an embodiment of the present invention is measured by TOF-SIMS under the conditions described later, and first, third, and A peak based on at least one of the four ions is measured.

(1-1) dust core 1 according to an embodiment of the first ion present invention, the following condition (hereinafter, also referred to as "measurement condition 1".) As measured by TOF-SIMS _{in, C} n H _A peak based on a first ion composed of at least one kind of ions represented by _2n-1 O ₂ ⁻ (n = 11 to 20) is measured. The first ion may be one type or a plurality of types. The first ions are usually a plurality of types.
Irradiated ions: Bi ³⁺
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Irradiation mode: Bunching mode

  Here, the bunching mode is a mode in which the ion beam irradiated on the sample is pulsed and the pulse width (the time difference between the front and the back of the beam) is narrowed to increase the resolution.

FIG. 3 is a diagram showing a part of a spectrum obtained by measuring with TOF-SIMS for each of the powder cores 1 manufactured in Example 1 and Comparative Examples 1 to 3 described later. FIG. 3 shows peaks based on C ₁₁ H ₂₁ O ₂ ⁻ , C ₁₂ H ₂₃ O ₂ ⁻ , and C ₁₃ H ₂₅ O ₂ ⁻ belonging to the first ions.

  In this specification, when the first intensity ratio described later is 0.01 or less, it is determined that there is no peak based on the first ions because the peak of the first ions cannot be distinguished from the measurement noise.

By measuring the peak based on the first ions, a powder core having excellent heat resistance can be obtained. The reason is not clear. There is a possibility that a substance having a carbon-hydrogen bond and having more properties as a so-called organic substance exists as a resin material. The first ion may have a chemical structure represented by the following formula (1).
_{CH 3 - (CH 2) x} -CH 2 -COO - (1)
x is an integer from 8 to 17

Since the resin that provides the resin material R included in the dust core 1 according to the embodiment of the present invention includes an acrylic resin, when the dust core 1 is measured by TOF-SIMS, the maximum mass / u of the peak is 71. A peak of .02 is measured. The chemical formula assumed from mass / u of the maximum value of this peak is C ₃ H ₃ O ₂ ^— , and from this chemical formula, it is considered that the negative ion giving this peak corresponds to an acrylate ion. The ratio of the intensity of the peak based on the first ions (also referred to as “first intensity ratio” in this specification) to the intensity of this peak (also referred to as “first reference intensity” in this specification) is at least one. Is preferably 0.03 or more, more preferably 0.05 or more, and particularly preferably 0.10 or more. Further, the number of first ions having a first intensity ratio of 0.03 or more is preferably 2 or more, more preferably 3 or more, and particularly preferably 4 or more. The first ions having a first intensity ratio of 0.05 or more are preferably two or more, more preferably three or more, and particularly preferably four or more. It is preferable that there are two or more types of first ions having a first intensity ratio of 0.10 or more.

(1-2) 2nd ion When the powder core 1 which concerns on one Embodiment of this invention is measured by TOF-SIMS, the peak based on the 2nd ion demonstrated below may be measured. In this specification, the maximum ion mass / u of the peak based on the ion is 0.5 / smaller than the mass / u of the maximum value of the peak based on the first ion. It is located between mass / u and means an ion other than the first ion. A plurality of second ions may be defined for one type of first ion. In this case, a plurality of peaks are measured in the mass / u region.

As shown in FIG. 3, for the dust core 1 according to one embodiment of the present invention manufactured according to the example as well as the dust core manufactured according to the comparative example, when measured by TOF-SIMS, Peaks based on the second ions were measured. As shown in FIG. 3, there are clearly two peaks of the second ion corresponding to C ₁₁ H ₂₁ O ₂ ^— which is a kind of the first ion.

  In the dust core 1 according to an embodiment of the present invention, the second intensity ratio, which is the ratio of the peak intensity of the first ions, to the sum of the intensity of the peaks of the second ions is 0.1 or more. Preferably, it is 0.2 or more.

  The specific chemical structure of the second ion is not clear. As will be described next, the second ion may be a fragment of a compound formed by the acrylic resin binding to Fe, which is a constituent element of the soft magnetic powder. That is, the carboxyl group (—COOH) of the acrylic resin used as the binder undergoes a dehydration reaction with the hydroxyl group (—OH) bonded to Fe present on the surface of the soft magnetic powder, so that the acrylic resin becomes a soft magnetic powder. Chemically bonds to the surface. There is a possibility that a part of the acrylic resin chemically bonded to the surface of the soft magnetic powder is fragmented together with Fe to form second ions.

  The second ions can be measured by a dust core other than the dust core 1 according to the embodiment of the present invention. However, in such a dust core, the peak based on the first ions is a noise level. The intensity ratio never exceeds 0.1.

(1-3) Third Ion When the powder core 1 according to an embodiment of the present invention is measured by TOF-SIMS under the measurement condition 1, the third ion represented by C ₅ H ₇ O ₃ ^—. A peak based on is measured.

  In the present specification, when the third intensity ratio described later is 0.01 or less, the peak of the third ion cannot be distinguished from the measurement noise, so that it is determined that there is no peak based on the third ion.

By measuring the peak based on the third ions, a powder core having excellent heat resistance can be obtained. The reason is not clear. Although the specific chemical structure of the third ion (C ₅ H ₇ O ₃ ⁻ ) is not clear, it has a carboxyl ion ((COO) ⁻ ) and a carbonyl group (> C═O), others are hydrogen, methylene It may be composed of a group and a methyl group.

  In the dust core 1 according to one embodiment of the present invention, the ratio of the peak intensity based on the third ions to the first reference intensity (also referred to as “third intensity ratio” in this specification) is 0.10 or more. It is preferable that it is 0.15 or more, and it is especially preferable that it is 0.20 or more.

(1-4) dust core 1 according to an embodiment of the fourth ion present invention, as measured by TOF-SIMS in measuring conditions _{1, C 7 H 11 O 2} - in the fourth ion represented A peak based on is measured.

  In the present specification, when the fourth intensity ratio described later is 0.01 or less, the peak of the third ion cannot be distinguished from the measurement noise, so that it is determined that there is no peak based on the third ion.

By measuring a peak based on the fourth ion, a powder core having excellent heat resistance is obtained. The reason is not clear. Although the specific chemical structure of the fourth ion (C ₇ H ₁₁ O ₂ ⁻ ) is not clear, it may be a heptenoic acid ion having an ethylenically unsaturated bond at any of the 2nd to 6th positions.

  In the dust core 1 according to one embodiment of the present invention, the ratio of the peak intensity based on the fourth ions with respect to the first reference intensity (also referred to as “fourth intensity ratio” in this specification) is 0.02 or more. It is preferable that it is 0.04 or more, and it is especially preferable that it is 0.06 or more.

  In some cases, the dust core 1 according to an embodiment of the present invention preferably contains P (phosphorus). Although the reason is not clear, when the dust core 1 contains P (phosphorus), it becomes easy to measure at least one of the first ion, the third ion, and the fourth ion, and the heat resistance of the dust core 1 is increased. It becomes easy to improve. P (phosphorus) contained in the powder core 1 may affect the physical properties and composition of the resin material R and contribute to the generation of the ions. The method for containing P (phosphorus) in the powder core 1 is not limited. P (phosphorus) may be included in the soft magnetic powder M, or a phosphorus-containing substance such as phosphate glass may be used in the manufacturing process of the powder core 1. It is particularly preferable that the soft magnetic powder M contains P.

(1-5) 5th ion In the powder core 1 which concerns on one Embodiment of this invention in which the peak based on 1st ion is measured, it is considered that it was produced | generated when the acrylic resin was decomposed | disassembled in oxidizing atmosphere. _The peak of ions represented by ₂ HO ⁻ (also referred to as “fifth ion” in the present specification) (the maximum peak mass / u is 41.01) is also measured. However, the intensity of the fifth peak tends to be smaller than the intensity of the fifth ion peak measured in the dust core where the peak based on the first ions is not substantially measured. Therefore, the dust core 1 according to an embodiment of the present invention may be in a state in which decomposition due to oxidation or the like of the resin-based material does not proceed relatively.

  Specifically, when the dust core 1 according to one embodiment of the present invention is measured by TOF-SIMS, the ratio of the peak intensity based on the fifth ion to the first reference intensity (referred to as “ 5), ”is preferably 10 or less, more preferably 7 or less, and particularly preferably 5 or less.

(2) Soft magnetic powder The material which comprises the soft magnetic powder M with which the powder core 1 which concerns on one Embodiment of this invention is provided is not limited. Examples of such a material include a crystalline magnetic material and an amorphous magnetic material, and a material having a crystalline portion and an amorphous portion. The material constituting the soft magnetic powder M may be one type or a plurality of types. When the soft magnetic powder M is composed of a plurality of types of materials, the composition and blending ratio of each constituent material are not limited.

  The crystalline magnetic material satisfies that it is crystalline (a general X-ray diffraction measurement can obtain a diffraction spectrum having a clear peak that can identify the type of material) and a soft magnetic material. As long as the specific type is not limited. Specific examples of crystalline magnetic materials include Fe-Si-Cr alloys, Fe-Ni alloys, Fe-Co alloys, Fe-V alloys, Fe-Al alloys, Fe-Si alloys, Fe-Si. -Al-based alloys, carbonyl iron and pure iron are mentioned. In order to facilitate measurement of at least one of the first ion, the third ion, and the fourth ion, it is particularly preferable that these crystalline magnetic materials contain P.

  The amorphous magnetic material is amorphous (a diffraction spectrum having a clear peak that can identify the type of material cannot be obtained by general X-ray diffraction measurement), and is a soft magnetic material. As long as the above is satisfied, the specific type is not limited. Specific examples of the amorphous magnetic material include Fe—P—C—B—Si alloys, Fe—Si—B alloys, Fe—PC—C alloys, and Co—Fe—Si—B alloys. . In order to facilitate measurement of at least one of the first ion, the third ion, and the fourth ion, it is particularly preferable that these amorphous magnetic materials contain P.

More specific examples of amorphous magnetic material, composition _formula, shown in _{Fe 100at% -a-b-c} -x-y-z-t Ni a Sn b Cr c P x C y B z Si t 0 at% ≦ a ≦ 10 at%, 0 at% ≦ b ≦ 3 at%, 0 at% ≦ c ≦ 6 at%, 6.8 at% ≦ x ≦ 10.8 at%, 2.2 at% ≦ y ≦ 9.8 at%, Examples include Fe-based amorphous alloys in which 0 at% ≦ z ≦ 4.2 at% and 0 at% ≦ t ≦ 7 at%. In the above composition formula, Ni, Sn, Cr, B, and Si are optional added elements.

  A preferable addition amount range of each element of the Fe-based amorphous alloy is as follows. The addition amount a of Ni is preferably 0 at% or more and 6 at% or less, and more preferably 0 at% or more and 4 at% or less. The addition amount b of Sn is preferably 0 at% or more and 2 at% or less, and more preferably 1 at% or more and 2 at% or less. The addition amount c of Cr is preferably 0 at% or more and 2 at% or less, and more preferably 1 at% or more and 2 at% or less. The addition amount x of P is preferably set to 8.8 at% or more so that at least one of the first ion, the third ion, and the fourth ion can be easily measured. The addition amount y of C is preferably 5.8 at% or more and 8.8 at% or less. The addition amount z of B is preferably 0 at% or more and 3 at% or less, and more preferably 0 at% or more and 2 at% or less. The addition amount t of Si is preferably 0 at% or more and 6 at% or less, and more preferably 0 at% or more and 2 at% or less.

  The material having a crystalline part and an amorphous part may be a mixture of a crystalline magnetic material and an amorphous magnetic material, or a material having an amorphous phase and a crystalline phase. Also good. An example of the latter material is an Fe-based alloy in which a crystalline daughter phase is dispersed and precipitated in an amorphous matrix by containing an element that promotes crystal precipitation such as Nb, Cu, and Si. Is done.

  The shape of the soft magnetic powder M contained in the powder core 1 according to the embodiment of the present invention is not limited. The shape of the soft magnetic powder M may be spherical or non-spherical. In the case of a non-spherical shape, it may be a shape having a shape anisotropy such as a flat shape, a scale shape, an oval sphere, a droplet shape, a needle shape, or an indefinite shape having no special shape anisotropy. There may be.

  The shape of the soft magnetic powder M may be the shape obtained in the stage of producing the soft magnetic powder M (the atomizing method is given as a specific example), or the produced soft magnetic powder M is subjected to secondary processing. A shape obtained by performing flattening with an attritor or the like is given as a specific example. Examples of the former shape include a spherical shape, an oval shape, a droplet shape, and a needle shape. Examples of the latter shape include a flat shape and a scale shape.

  The particle diameter of the soft magnetic powder M contained in the powder core 1 according to the embodiment of the present invention is not limited. If this particle size is defined by the average particle size D50 (particle size when the volume cumulative value in the volume distribution of the particle size of the soft magnetic powder M measured by the laser diffraction scattering method is 50%), it is usually from 1 μm. The range is 20 μm. From the viewpoint of enhancing the handleability and the viewpoint of increasing the packing density of the soft magnetic powder M in the dust core 1, the average particle diameter D50 of the soft magnetic powder M is preferably 2 μm or more and 15 μm or less, and 3 μm or more and 10 μm or less. More preferably, it is more preferably 4 μm or more and 7 μm or less.

  The content of the soft magnetic powder M in the powder core 1 according to the embodiment of the present invention is not limited. Depending on the application, it is appropriately set in consideration of the composition of the resin-based material, the manufacturing process, and the like.

(3) Resin-type material The resin-type material R with which the powder core 1 which concerns on one Embodiment of this invention is provided is insulating, Comprising: Resin which provides the said material contains acrylic resin. In this specification, “resin-based material R” is a resin and / or a resin-based component (a component in which at least a part of the resin is changed in composition, and a (part) thermal decomposition product of the resin is a specific example. In the resin-based material R according to this embodiment, the resin that provides the resin-based material R includes an acrylic resin.

  The acrylic resin only needs to contain a structural unit based on at least one of acrylic acid and a derivative thereof, and may be a homopolymer or a copolymer. Examples of acrylic acid derivatives include acrylic acid esters, methacrylic acid and esters thereof, and acrylamide. When the acrylic resin is a copolymer, the copolymer may contain a constitutional unit other than the constitutional unit based on at least one of acrylic acid and its derivative, and the type of compound that gives the constitutional unit Is not limited. Specific examples of such compounds include olefins such as ethylene and vinyl esters such as vinyl acetate. The acrylic resin may have a crosslinked structure. The crosslinking agent in that case is not limited, and examples thereof include polyisocyanate compounds.

  The resin that provides the resin material may contain a resin other than the acrylic resin. Examples of such resins include silicone resins, epoxy resins, phenol resins, urea resins, melamine resins, and the like.

  As shown in FIG. 2, the resin-based material R is located between the adjacent soft magnetic powders M and M in the dust core 1 to fix and insulate the soft magnetic powders M and M. This contributes to maintaining the shape and insulation of the core 1. In general, when the dust core is subjected to a heating test, there is a concern that the above-described fixing function and / or insulating function of the resin-based material may be deteriorated. However, the dust core 1 according to one embodiment of the present invention is As described above, since the resin-based material R in which at least one of the first ion, the third ion, and the fourth ion is measured when measured by TOF-SIMS, the magnetic characteristics are not easily lowered after the heating test.

(4) Manufacturing method of dust core The manufacturing method of the dust core 1 which concerns on one Embodiment of this invention is not limited. If an example of this manufacturing method is given, the powder core 1 can be obtained by press-molding the composition containing soft-magnetic powder and resin, and heating the obtained molded object.

  In this production method, the pressurizing condition and heating condition are appropriately set according to the mechanical and magnetic properties required for the dust core, the composition of the composition, and the like. As an example of the heating conditions, heating in an oxidizing atmosphere and heating in a non-oxidizing atmosphere can be given. As described above, since the dust core 1 according to an embodiment of the present invention includes the resin material R containing a component based on an acrylic resin, the composition to be pressure-molded is an acrylic resin. Containing.

  When the dust core 1 is measured by TOF-SIMS, it is easy to obtain the resin material R in which at least one of the first ion, the third ion, and the fourth ion is measured from a composition containing an acrylic resin. Thus, the heating condition preferably includes heating in an oxidizing atmosphere, and the temperature is preferably 300 ° C. or higher and 400 ° C. or lower, and more preferably 355 ° C. or higher and 400 ° C. or lower. Furthermore, it is particularly preferable that the temperature is 360 ° C. or higher and 400 ° C. or lower. In addition, from the viewpoint of more stably relieving the strain applied to the soft magnetic powder M by pressure molding, it is preferable to perform heating at 400 ° C. or higher. In this case, the powder core 1 is made of the resin material R Is preferably heated in a non-oxidizing atmosphere. Therefore, when heating in an oxidizing atmosphere and heating in a non-oxidizing atmosphere are performed, heating is performed at 300 ° C. or higher and 400 ° C. or lower in an oxidizing atmosphere, and then heating is performed at 400 ° C. or higher in a non-oxidizing atmosphere. It is preferable.

  The above composition to be pressure-molded may contain components other than the soft magnetic powder and the resin. Examples of such components include inorganic components such as glass and lubricants such as metal soaps. By including a component (for example, phosphate glass) containing P (phosphorus) in the composition, when the powder core 1 is measured by TOF-SIMS, at least one of the first ion, the third ion, and the fourth ion is present. It may be easy to measure. The method for preparing the composition is not limited. The material constituting the composition may be obtained simply by kneading, or the slurry containing the material constituting the composition may be dried and pulverized to form a granulated powder.

2. Electrical / Electronic Component An electrical / electronic component according to an embodiment of the present invention includes a dust core 1 according to an embodiment of the present invention, a coil, and a connection terminal connected to each end of the coil. . Here, at least a part of the dust core 1 is disposed so as to be located in an induced magnetic field generated by the current when a current is passed through the coil via the connection terminal.

  An example of such an electric / electronic component is the toroidal core 10 shown in FIG. The toroidal core 10 includes a coil 2a formed by winding a covered conductive wire 2 around a ring-shaped dust core 1. The ends 2d and 2e of the coil 2a can be defined in the portion of the conductive wire located between the coil 2a formed of the wound covered conductive wire 2 and the ends 2b and 2c of the covered conductive wire 2. As described above, in the electrical / electronic component according to the present embodiment, the member constituting the coil and the member constituting the connection terminal may be composed of the same member.

  An electric / electronic component according to an embodiment of the present invention includes a dust core having a shape different from that of the dust core 1 according to the embodiment of the present invention. A specific example of such an electric / electronic component is an inductance element 20 shown in FIG. FIG. 5 is a perspective view showing a part of the entire configuration of the inductance element 20 according to the embodiment of the present invention. In FIG. 5, the lower surface (mounting surface) of the inductance element 20 is shown in an upward posture. FIG. 6 is a partial front view showing a state in which the inductance element 20 shown in FIG. 5 is mounted on the mounting substrate 10.

  An inductance element 20 shown in FIG. 5 includes a dust core 3, an air core coil 5 as a coil embedded in the dust core 3, and a connection terminal electrically connected to the air core coil 5 by welding. And a pair of terminal portions 4.

  The air-core coil 5 is formed by spirally winding a conductive wire with an insulating coating. The air-core coil 5 includes a winding part 5a and lead-out end parts 5b and 5b drawn from the winding part 5a. The number of turns of the air-core coil 5 is appropriately set according to the required inductance.

  As shown in FIG. 5, in the dust core 3, an accommodation recess 30 for accommodating a part of the terminal portion 4 is formed on the mounting surface 3 a for the mounting substrate. The storage recesses 30 are formed on both sides of the mounting surface 3 a and are formed to be released toward the side surfaces 3 b and 3 c of the powder core 3. Part of the terminal portion 4 protruding from the side surfaces 3 b and 3 c of the powder core 3 is bent toward the mounting surface 3 a and stored in the storage recess 30.

  The terminal portion 4 is formed of a thin plate-like Cu base material. The terminal part 4 is exposed on the outer surface of the dust core 3 and the connection end part 40 embedded in the dust core 3 and electrically connected to the lead-out ends 5b, 5b of the air-core coil 5. The powder core 3 includes a first bent portion 42a and a second bent portion 42b that are bent in order from the side surfaces 3b and 3c to the mounting surface 3a. The connection end 40 is a welded portion that is welded to the air-core coil 5. The first bent portion 42 a and the second bent portion 42 b are solder joint portions that are soldered to the mounting substrate 100. The solder joint portion is a portion of the terminal portion 4 that is exposed from the dust core 3 and means a surface that faces at least the outside of the dust core 3.

  The connection end portion 40 of the terminal portion 4 and the extraction end portion 5b of the air-core coil 5 are joined by resistance welding.

As shown in FIG. 6, the inductance element 20 is mounted on the mounting substrate 100.
A conductor pattern that is electrically connected to an external circuit is formed on the surface of the mounting substrate 100, and a pair of land portions 110 for mounting the inductance element 20 is formed by a part of the conductor pattern.

  As shown in FIG. 6, in the inductance element 20, the mounting surface 3 a is directed to the mounting substrate 100 side, and the first bent portion 42 a and the second bent portion 42 b that are exposed to the outside from the dust core 3 are mounted. The solder layer 120 is bonded to the land portion 110 of the substrate 100.

  In the soldering process, after the paste-like solder is applied to the land part 110 in the printing process, the inductance element 20 is mounted so that the second bent part 42b faces the land part 110, and the solder is applied in the heating process. Melt. As shown in FIGS. 5 and 6, the second bent portion 42 b faces the land portion 110 of the mounting substrate 100, and the first bent portion 42 a is exposed on the side surfaces 3 b and 3 c of the inductance element 20. The solder layer 120 is fixed to the land portion 110 and is sufficiently spread and fixed to the surfaces of both the second bent portion 42b and the first bent portion 42a which are solder joint portions.

  Examples of electric / electronic components other than the toroidal core 10 and the inductance element 20 described above include a reactor and a transformer.

3. Electrical / Electronic Device An electrical / electronic device according to an embodiment of the present invention is mounted with an electrical / electronic component including the dust core according to the embodiment of the present invention. Examples of such electric / electronic devices include a power supply device including a power switching circuit, a voltage raising / lowering circuit, and a smoothing circuit, a small portable communication device, and the like.

  When such an electric / electronic device is used in a vehicle, it is strongly required to have excellent operational stability even when placed in a high temperature environment for a long period of time. In order to meet these demands, it is necessary that each of the electric and electronic components incorporated in the electric and electronic equipment has excellent operational stability even when placed in a high temperature environment for a long period of time. Since the electric / electronic component according to an embodiment of the present invention includes the dust core having excellent heat resistance as described above, the electric / electronic device on which the component is mounted can be easily applied to in-vehicle use. .

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, according to the present invention, it is possible to determine whether or not the dust core is excellent in heat resistance by measuring with TOF-SIMS. Further, by measuring with TOF-SIMS, it can be determined whether or not the dust core contains P (phosphorus) in each of the magnetic powder and the resin-based material.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

Example 1
Using a water atomization method, non-obtained obtained by weighing to a composition of Fe _{74.43 at%} Cr _{1.96 at%} P _{9.04 at%} C _{2.16 at%} B _{7.54 at%} Si _{4.87 at%} A crystalline soft magnetic powder was prepared as a soft magnetic powder. The particle size distribution of the obtained soft magnetic powder was measured by volume distribution using “Microtrack particle size distribution measuring device MT3300EX” manufactured by Nikkiso Co., Ltd. As a result, the average particle diameter (D50), which is 50% in the volume distribution, was 10.6 μm.

  100 parts by mass of the above soft magnetic powder, 1.7 parts by mass of an acrylic resin, 0.6 parts by mass of an inorganic component made of phosphate glass, and 0.3 parts by mass of a lubricant made of zinc stearate are mixed. To obtain a slurry.

  The obtained slurry was pulverized after drying, and fine powder of 300 μm or less and coarse powder of 850 μm or more were removed using a sieve having an opening of 300 μm and a sieve of 850 μm to obtain granulated powder.

  The obtained granulated powder was filled in a mold and subjected to pressure molding at a surface pressure of 1.8 GPa to obtain a molded body having a ring shape. The obtained molded body was heated in the atmosphere (oxidizing atmosphere) at 360 ° C. for 10 hours and then heat-treated in a nitrogen atmosphere (non-oxidizing atmosphere) at 470 ° C. for 1 hour to obtain an outer diameter of 20 mm × A dust core having a ring shape with an inner diameter of 12 mm and a thickness of 7 mm was obtained.

(Comparative Example 1)
Except that the phosphate glass was not blended during the preparation of the slurry, the same operation as in Example 1 was performed to obtain a dust core.

(Comparative Example 2)
Except having changed the kind of soft-magnetic powder into the Fe-Si-B-Cr type | system | group amorphous (average particle diameter (D50): 50micrometer), operation similar to Example 1 was performed and the dust core was obtained. Further, this Fe—Si—B—Cr-based amorphous alloy had no addition of P.

(Comparative Example 3)
Except that the phosphate glass was not blended during the preparation of the slurry, the same operation as in Comparative Example 2 was performed to obtain a dust core.

(Test Example 1) Measurement by TOF-SIMS The measurement by TOF-SIMS was performed for each of the dust cores produced by the examples and comparative examples. The measurement apparatus and measurement conditions were as follows.
Measuring device: TOF-SIMS5 (manufactured by ION-TOF)
Irradiation ion: Bi ³⁺ (Liquid metal ion source: Bi)
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Measurement mode: Bunching mode (High current bunching mode)

  Negative ions having a mass / u in the range of 20 to 250 were measured.

Specific measurement items were as follows. The peak intensity was obtained by fitting assuming that each peak has a normal distribution.
Measurement of presence / absence of peak and peak intensity (first reference intensity) based on acrylate ion (C ₃ H ₃ O ₂ ⁻ ) Measurement of presence / absence of peak and peak intensity based on first ion Peak based on second ion・ Measurement of presence and peak intensity based on third ion ・ Measurement of presence and peak intensity based on fourth ion ・ Measurement of presence and peak intensity based on fifth ion Measurement A portion of the resulting spectrum is shown in FIGS.

  As a result of the measurement, the peak based on the acrylate ion was measured for any powder core. Therefore, the first intensity ratio, the second intensity ratio, the third intensity ratio, the fourth intensity ratio, and the fifth intensity ratio were obtained from the measurement results. These results are shown in Table 1 together with the chemical formula of each ion assumed from the value of mass / u.

  The meanings of numerical values in each column in Table 1 are as follows.

In the column “mass / u of maximum value of peak”, the maximum value of mass / u of each peak is shown. The negative ion in which the assumed chemical formula is C ₃ H ₃ O ₂ ^— (the maximum peak mass / u is 71.01) is shown in the row of Example 1 and Comparative Examples 1 to 3 above. The measured value (count number) of the peak intensity based on the above, that is, the first reference intensity is shown.

  The first intensity ratio is shown in the first ion row. As described above, the first intensity ratio is the ratio of the intensity of the peak based on the first ions to the first reference intensity. When the first intensity ratio was 0.01 or less, it was judged that there was no peak based on the first ions because the peak based on the first ions could not be distinguished from the measurement noise.

  The second intensity ratio is shown in the second ion row. As described above, the second intensity ratio is the ratio of the peak intensity of the first ions to the sum of the intensity of the peaks of the second ions. When the second intensity ratio is less than 0.05, the peak based on the first ions cannot be distinguished from the measurement noise, so “<0.05” is displayed.

  The third intensity ratio is shown in the third ion row. As described above, the third intensity ratio is the ratio of the intensity of the peak based on the third ions to the first reference intensity. When the third intensity ratio was 0.01 or less, the peak based on the third ion could not be distinguished from the measurement noise, so that it was determined that there was no peak based on the third ion.

  The fourth intensity ratio is shown in the fourth ion row. As described above, the fourth intensity ratio is the ratio of the intensity of the peak based on the fourth ion to the first reference intensity. When the fourth intensity ratio was 0.01 or less, the peak based on the fourth ion could not be distinguished from the measurement noise, so it was determined that there was no peak based on the fourth ion.

  The fifth ion ratio is shown in the fifth ion row. As described above, the fifth intensity ratio is the ratio of the intensity of the peak based on the fifth ion to the first reference intensity.

(Test Example 2) Evaluation of heat resistance Copper wire winding was applied to a dust core having a ring shape produced according to Examples and Comparative Examples, and a BH analyzer ("SY-8217" manufactured by Iwasaki Tsushinki Co., Ltd.) was used. The core loss Pc ₀ (unit: kW / m ³ ) was measured under the conditions of a frequency of 100 kHz and a maximum magnetic flux density of 100 mT.

A heating test was performed on the dust core around which the copper wire was wound, which was left in an atmosphere of 250 ° C. for 1000 hours. After the heating test, the core loss Pc ₁ (unit: kW / m ³ ) was measured under the above conditions. Based on the following formula, the core loss change rate ΔPc (unit:%) was calculated.
ΔPc = (Pc ₁ −Pc ₀ ) / Pc ₀ × 100

  Table 2 shows the measurement result of the core loss and the change rate of the core loss.

  As shown in Table 2, the dust core according to Example 1 in which the first ion, the third ion, and the fourth ion were measured has a small core loss change rate ΔPc and is excellent in heat resistance. In contrast, the dust cores according to Comparative Examples 1 to 3 in which none of the 1 ion, the 3rd ion, and the 4th ion were measured have a large core loss change rate ΔPc and are inferior in heat resistance.

  Thus, the ΔPc of the dust core of Example 1 is small because of the presence of the first ions, the third ions, and the fourth ions, the soft magnetic powder in the dust core generated by heating. This is considered to be because the stress generated in the film was relaxed appropriately, and the strain in the soft magnetic powder became difficult to accumulate. Moreover, although the reason is not certain, the generation of the first ion, the third ion, and the fourth ion in the resin-based material during the heat treatment in the atmosphere is promoted by P existing in the soft magnetic powder or the phosphate glass. Inferred.

  The dust core of the present invention is suitable as a power supply device including a power supply switching circuit, a voltage raising / lowering circuit, a smoothing circuit, and the like, particularly as a power supply device for in-vehicle use, a small portable communication device, and the like.

DESCRIPTION OF SYMBOLS 1 ... Powder core M ... Soft magnetic powder R ... Resin-type material 10 ... Toroidal core 2 ... Coated conductive wire 2a ... Coil 2b, 2c ... End part 2d of coated conductive wire 2, 2e ... End part 20 of coil 2a ... Inductance Element 3... Powder core 3 a. Mounting surface 3 b, 3 c of powder core 3. Side surface 4 of powder core 3. Terminal portion 5. Air core coil 5 a ... Winding portion 5 b of air core coil 5. The lead-out end 30 ... the storage recess 40 ... the connection end 42a ... the first bent portion 42b ... the second bent portion 100 ... the mounting substrate 110 ... the land portion 120 ... the solder layer

Claims (17)

A dust core comprising soft magnetic powder and an insulating resin material,
The resin that gives the resin material contains an acrylic resin,
When the dust core is measured by TOF-SIMS under the following conditions, it is based on a first ion composed of at least one of the ions represented by C _n H _2n-1 O ₂ ⁻ (n = 11 to 20). A dust core characterized in that a peak is measured.
Irradiated ions: Bi ³⁺
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Irradiation mode: Bunching mode C ₃ H ₃ O ₂ to be measured when measuring the dust core by TOF-SIMS under the conditions as described in claim 1 ^- with respect to the intensity of the peak based on, of the intensity of the peak based on the first ion The dust core according to claim 1, wherein the first strength ratio as a ratio is 0.03 or more.   When measuring the said powder core by TOF-SIMS on the conditions described in Claim 1, the mass / u of the maximum value of the peak based on the ion is the mass of the maximum value of the peak based on the first ion. At least one peak based on a second ion that is an ion other than the first ion is located between / u and mass / u smaller than the mass / u by 0.5. The dust core according to claim 1, wherein a second intensity ratio, which is a ratio of the peak intensity of the first ions to the sum of the intensity of the peaks of the second ions, is 0.1 or more. A dust core comprising soft magnetic powder and an insulating resin material,
The resin that gives the resin material contains an acrylic resin,
Wherein the dust core as measured by TOF-SIMS under the following conditions, C ₅ H ₇ O ₃ ^- dust core that peaks based on the third ion is characterized in that it is determined to be represented by.
Irradiated ions: Bi ³⁺
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Irradiation mode: Bunching mode C ₃ H ₃ O ₂ that will be measured when measuring the dust core by TOF-SIMS under the conditions as described in claim 4 ^- with respect to the intensity of the peak based on, of the intensity of the peak based on the third ion The powder core according to claim 4, wherein the third strength ratio, which is the ratio, is 0.05 or more. A dust core comprising soft magnetic powder and an insulating resin material,
The resin that gives the resin material contains an acrylic resin,
Wherein the dust core as measured by TOF-SIMS under the following _conditions, C _{7 H} 11 _{O 2} ^- dust core that peaks based on the fourth ion is characterized in that it is determined to be represented by.
Irradiated ions: Bi ³⁺
Acceleration voltage: 25 keV
Irradiation current: 0.3 pA
Irradiation mode: Bunching mode C ₃ H ₃ O ₂ to be measured when measuring the dust core by TOF-SIMS under the conditions as described in claim 6 ^- to the intensity of the peak based on, of the intensity of the peak based on the fourth ion The dust core according to claim 6, wherein the fourth strength ratio, which is the ratio, is 0.02 or more. Based on C ₂ HO ⁻ against the intensity of the peak based on C ₂ H ₃ O ₂ ⁻ measured when the dust core is measured by TOF-SIMS under the conditions described in claim 1, 4 or 6 The dust core according to any one of claims 1 to 7, wherein a fifth intensity ratio, which is a ratio of peak intensities, is 10 or less.   The dust core according to any one of claims 1 to 8, comprising P.   The powder core according to any one of claims 1 to 9, wherein the soft magnetic powder has an amorphous part. The soft magnetic powder is an Fe-based amorphous alloy, Ni is 0 atomic% to 10 atomic%, Sn is 0 atomic% to 3 atomic%, Cr is 0 atomic% to 6 atomic%, P 3.0 atomic% to 11 atomic%, C 1.0 atomic% to 10 atomic%, B 0 atomic% to 9 atomic%, and Si 0 atomic% to 6 atomic%, The powder core according to any one of claims 1 to 10. It is a manufacturing method of the compacting core according to any one of claims 1 to 11,
A compact core comprising: a compact core obtained by pressing the composition containing the soft magnetic powder and the resin to obtain a compact, and heating the resulting compact . Manufacturing method . The method for manufacturing a powder core according to claim 12, wherein the heating of the compact includes heating in an oxidizing atmosphere and subsequent heating in a non-oxidizing atmosphere. The method for producing a powder core according to claim 12 or 13, wherein the composition contains an inorganic component. The method for producing a powder core according to claim 14, wherein the inorganic component contains P. An electrical / electronic component comprising a dust core, a coil, and a connection terminal connected to each end of the coil according to any one of claims 1 to 11 , wherein at least a part of the dust core is An electric / electronic component arranged so as to be located in an induced magnetic field generated by the current when a current is passed through the coil via the connection terminal. 17. An electric / electronic device in which the electric / electronic component according to claim 16 is mounted, wherein the electric / electronic component is connected to a substrate by the connection terminal.