KR20150090839A - Electronic component and electronic apparatus - Google Patents

Abstract

The present invention relates to an electronic component and an electronic apparatus. The electronic component has a section made of a molded body containing powder and/or pellets having magnetism and insulating and the magnetic properties of the section of the molded body remain excellent even when the size of the electronic component is reduced. The electronic component has the section made of the molded body containing powder and/or pellets and a component based on a binder, wherein a distance between terminals is less than or equal to 4 mm. In the section made of the molded body, an air gap parameter (P1) defined by formula (1) below is 0.3-0.8 inclusive. P1 = Rv/(Rv + Rb) (1), where Rv (unit: volume%) is an air gap rate after the molding-process of the section made of the molded body and Rb (unit: volume%) is a volume rate of the element based on the binder after the molding-process of the section made of the molded body.

Description

[0001] ELECTRONIC COMPONENT AND ELECTRONIC APPARATUS [0002]

TECHNICAL FIELD The present invention relates to an electronic component having a portion formed of a molded product containing powdered particles having magnetic properties, and an electronic device in which the electronic component is mounted.

BACKGROUND ART [0002] Portable electronic devices are being rapidly replaced from a cellular phone to a smart phone having a small size and a high functionality. In such a multifunctional portable electronic device, it is very important to increase the usable time by lengthening the usable time by one charge. One of the means for solving this problem is to increase the number of power supply circuits provided in the electronic apparatus and to control the operation of the respective circuits in accordance with the operation of the individual apparatuses and units connected to the circuit (in a specific example, And when not used, the operation of the power supply circuit connected thereto can be terminated), thereby reducing the power consumption of the electronic apparatus. As the power supply circuit increases, a large number of inductance elements for noise suppression, rectification, and smoothing (see, for example, Patent Document 1) are required. For this reason, the number of inductance elements used in portable electronic devices tends to increase.

However, since the size of the portable electronic device is naturally limited, it is required to reduce the size of the inductance element whose number of use increases. Specifically, the core disposed between the two terminals of the inductance element is required to maintain insulation property so as not to conduct current in the core. The distance between the two terminals (in this specification, The inductance element may be downsized to such an extent that the distance between the two terminals is referred to as " inter-terminal distance ") of 4 mm or less.

Japanese Laid-Open Patent Publication No. 2006-13066

The core of the inductance element is usually composed of a molded body containing a powdered body having magnetism (in this specification, a portion made of the molded body in an electronic part is also referred to as a " molded body portion "). When the inductance element is miniaturized as described above, the magnetic flux density of the magnetic flux density of the magnetic flux density of the molded body is increased by forming the molded body portion (core) by using an alloy magnetic powder having a high saturation magnetic flux density so that the inductance element has an appropriate direct current superimposition characteristic. (Magnetic permeability) is preferably increased.

Generally, miniaturization of the inductance element is realized by increasing the switching frequency of the switching power supply. To do so, it is necessary to reduce the core loss of the inductance element. Likewise, when the inductance element is operated at a high frequency, it is also desirable to increase the resistivity of the molded body portion (core) of the inductance element that affects the core loss, thereby enhancing the insulation of the molded body portion (core). Further, considering that the inductance element is mounted using the high-density mounting technique, it is necessary to maintain the strength of the molded body portion (core) so that it can be provided for practical use.

From the viewpoint of suppressing the deterioration of the insulating property and the strength of the molded part (core), the insulating property and the binding property between the powdered particles disposed closest to each other in the molded part constituting the molded part (core) It is effective to raise by. However, from this point of view, when the amount of the binder when forming the raw material containing the powdery material is increased, deterioration of the core loss and lowering of the magnetic permeability of the obtained molded body portion (core) may occur.

The above problem is not limited to the inductance element, and it is feared that similar problems arise with miniaturization of other electronic parts having a part formed of a compact containing the magnetic material powder.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide an electronic component having a portion (molded body portion) formed of a molded body containing magnetic powder and having a small size, ) Characteristics of the electronic component.

One aspect of the present invention that is provided to solve the above problems is an electronic component having a portion composed of a powdered body having magnetic properties and a molded body containing a binder system component and having a distance between terminals of 4 mm or less, , And a void parameter (P1) defined by the following equation (i) is 0.3 or more and 0.8 or less.

P1 = Rv / (Rv + Rb) (i)

Here, Rv (unit: volume%) is a porosity after molding of the portion formed of the molded product, and Rb (unit: volume%) is a volume ratio of the binder component after the molding process .

When the porosity parameter P1 is in the above range, it is possible to have an appropriate amount of the binder system component in a region other than the region occupied by the powdery body having magnetism in the molded body portion, It is possible to obtain an electronic part having excellent magnetic characteristics without significantly hindering it.

The electronic component is a member made of the same material as that of the part made of a molded product containing magnetic powder and having a measurement electrode distance of 2 to 4 mm and a resistance value measured by applying a direct current voltage of 15 V Is preferably 10 k [Omega] m or more.

The electronic component may be an inductance element made of a core made of a compact containing the magnetic powder.

It is preferable that the specific magnetic permeability at a frequency of 100 kHz is 20 or more.

The core loss measured at a frequency of 100 kHz and a maximum magnetic flux density of 100 mT may be less than 1500 kW / m < 3 >, and the portion of the electronic component formed of the molded product may be measured at a frequency of 100 kHz and a maximum magnetic flux density of 50 mT. The loss may be less than 120 kW / m 3.

The part of the electronic component of the molded article may be formed by adjusting the void parameter (P1) by changing the content of the binder with respect to the raw material in molding the raw material containing the magnetic powder and the binder do. In this way, it is easy to adjust the air gap parameter P1.

The surface of the molded part of the electronic part after the molding is observed with a secondary electron microscope at an observation magnification of 3,000 times at an accelerating voltage of 1.5 kV and the powder determination ratio of the observed image is 15% . It can be approximated that the above determination ratio has a proportional relationship with the pore parameter P1.

It is preferable that the above-mentioned powder having a magnetic property contained in a portion formed of the molded article of the electronic component has a particle size distribution represented by the following formula (ii).

(D ₉₀ - D ₁₀ ) / D ₅₀ ? 2.0 (ii)

Here, D ₁₀ , D ₅₀ and D ₉₀ are respectively the particle diameter (unit: μm) corresponding to 10% by volume of the integrated value in the particle size distribution of the powder particles measured using the laser diffraction scattering particle size distribution measuring apparatus, (Unit: 占 퐉) corresponding to the cumulative value of 50 volume% and the particle diameter (unit: 占 퐉) corresponding to the cumulative value of 90 volume%.

When the above relationship is satisfied, contact between the fine particles having magnetism is not likely to occur, and the insulating property tends to be improved.

Another aspect of the present invention is an electronic device in which the electronic component is mounted. As described above, even if the electronic component according to the present invention is small in size, the mechanical characteristics and the insulating property of the molded product part are not degraded well. Therefore, the problem such as breakage does not occur well, and the problem of insulation breakdown does not occur well. Therefore, even when the electronic device mounted with the electronic component according to the present invention is miniaturized, defects derived from the electronic component do not occur well and the operation stability is excellent.

In the electronic part related to the present invention, since the pore parameter P1 of the molded part is controlled in an appropriate range, the molded part is excellent in insulating property and the magnetic property And the pressure ring strength can be kept strong enough for practical use.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view partially showing an entire configuration of an inductance element according to an embodiment of the present invention. FIG.
Fig. 2 is a partial front view showing a state in which the inductance element shown in Fig. 1 is mounted on a mounting substrate. Fig.
3 is a graph showing the relationship between the specific resistance and the porosity based on the results of this embodiment.
4 is a graph showing the relationship between the specific permeability and the porosity based on the results of this embodiment.
5 is a graph showing the relationship between the core loss and the porosity based on the results of this embodiment.
6 is a graph showing the relationship between the pressing strength and the porosity based on the results of this embodiment.
7 is a graph showing the relationship between the relative resistivity and the pore parameter P1 based on the results of this embodiment.
Fig. 8 is a graph showing the relationship between the specific permeability and the pore parameter P1, based on the results of this embodiment.
9 is a graph showing the relationship between the relative position of the core loss and the air gap parameter P1 based on the results of this embodiment.
10 is a graph showing the relationship between the pressing strength and the pore parameter P1 based on the results of this embodiment.
11 is a graph showing the particle size distribution (integrated value) of the powder (soft magnetic powder) having magnetic properties according to the present embodiment.
12 is a graph showing the relationship between the determination ratio of the magnetic powdered powder (soft magnetic powder) and the gap parameter P1 based on the results of this embodiment.

Hereinafter, with respect to the embodiment of the present invention, the case where the electronic component is the inductance element shown in Figs. 1 and 2 will be described as a specific example.

1. Inductance element

Fig. 1 is a perspective view partially showing the overall configuration of an inductance element 1 according to an embodiment of the present invention. Fig. In Fig. 1, the lower surface (mounting surface) of the inductance element 1 is shown in an upward posture. Fig. 2 is a partial front view showing a state in which the inductance element 1 shown in Fig. 1 is mounted on the mounting substrate 10. Fig.

The inductance element 1 shown in Fig. 1 includes a pressure powder core 3, an air core coil 2 as a coil embedded in the press powder core 3, And a pair of terminal portions 4 that are electrically connected to the base 2.

The air-core coil 2 is formed by spirally winding an insulated conductor wire. The air core coil 2 has a winding section 2a and lead end portions 2b and 2b drawn out from the winding section 2a. The number of windings of the air-core coil 2 is appropriately set in accordance with the required inductance.

1, a housing recess 30 for accommodating a part of the terminal portion 4 is formed in the mounting surface 3a of the compaction core 3 with respect to the mounting board. The accommodating concave portion 30 is formed on both sides of the mounting surface 3a and is formed so as to be released toward the side surfaces 3b and 3c of the compaction core 3. A part of the terminal portion 4 protruding from the side surfaces 3b and 3c of the compaction core 3 is bent toward the mounting surface 3a and housed inside the accommodating concave portion 30. [

The terminal portion 4 is formed of a thin Cu-base substrate. The terminal portion 4 is exposed on the outer surface of the compaction core 3 and a connecting end portion 40 buried in the compaction core 3 and electrically connected to the lead end portions 2b and 2b of the air core coil 2 And a first curved portion 42a and a second curved portion 42b that are formed in order from the sides 3b and 3c of the compaction core 3 to the mounting surface 3a. The connecting end portion 40 is a welded portion welded to the air-core coil 2. The first curved portion 42a and the second curved portion 42b are solder joint portions that are soldered to the mounting substrate 10. [ The solder joint portion is a portion of the terminal portion 4 exposed from the pressurized core 3 and means at least a surface facing the outside of the compaction core 3.

The connection end portion 40 of the terminal portion 4 and the lead-out end portion 2b of the air-core coil 2 are joined by resistance welding.

As shown in Fig. 2, the inductance element 1 is mounted on the mounting substrate 10. Fig.

On the surface of the mounting substrate 10, a conductor pattern which conducts with an external circuit is formed. A part of the conductor pattern forms a pair of land portions 11 for mounting the inductance element 1 thereon.

As shown in Fig. 2, in the inductance element 1, the mounting surface 10a of the mounting surface 3a faces the first bending portion 42a and the first bending portion 42a, The second bending portion 42b is bonded to the land portion 11 of the mounting board 10 by the solder layer 12. [

In the soldering process, after the solder paste is applied to the land portion 11 in the printing process, the inductance element 1 is mounted so that the second curved portion 42b faces the land portion 11, The solder is melted. 1 and 2, the second curved portion 42b faces the land portion 11 of the mounting substrate 10 and the first curved portion 42a faces the side face 3b of the inductance element 1 The solder layer 12 on the fillet is fixed to the land portion 11 and the solder layer 12 on both surfaces of the second bending portion 42b as the solder joint portion and the first bending portion 42a So that it is fixed.

In the inductance element 1 shown in Figs. 1 and 2, the portions corresponding to the terminals arranged opposite to each other are two first curved portions 42a. The inter-terminal distance in the inductance element 1 shown in Figs. 1 and 2 is the distance between the two first curved portions 42a. This corresponds to the distance between the side face 3b and the side face 3c of the compaction core 3. That is, in the inductance element 1 shown in Figs. 1 and 2, the inter-terminal distance is determined according to the shape of the compaction core 3.

2. Molded part

The inductance element 1 according to one embodiment of the present invention includes a portion (molded body portion) formed of a molded body containing a powder having magnetic properties. In the inductance element 1 shown in Fig. 1, the compaction core 3 corresponds to a molded part.

The composition of the magnetic powder-containing powder contained in the molded part (compact powder core 3) is not limited. As a specific example of such a powder, there can be mentioned a soft magnetic powder containing a soft magnetic material. Specific examples of the soft magnetic powder include soft magnetic alloy powder such as Fe-based amorphous alloy powder, Fe-Ni-based alloy powder, Fe-Si-based alloy powder and pure iron powder (high purity iron powder), oxide soft magnetic powder such as ferrite, . The Fe-PCB-Si amorphous alloy, which is a kind of Fe-based amorphous alloy, is represented by Fe _100-abcxyzt Ni _a Sn _b Cr _c P _x C _y B _z Si _t , where 0 at% ≤ a ≤ 10 0 at% ≤ b ≤ 3 at%, 0 at% ≤ c ≤ 6 at%, 3.0 at% ≤ x ≤ 10.8 at%, 2.0 at% ≤ y ≤ 9.8 at%, 0 at% ≤ z ≤ 8.0 at%, 0 at% ≦ t ≦ 5.0 at%.

The powdered material having magnetism may be composed only of a magnetic material, or may be a mixture of a magnetic material and materials other than the material. As a specific example of such a case, granulated powder obtained by assembling a powder made of an alloy-based magnetic material with a resin-based material can be mentioned.

The particle size of the powder having magnetic properties is not limited. Basically, the smaller the particle diameter of the magnetic powder, the higher the formability tends to be. However, if the particle size becomes too small, the problem of coagulation tends to be presently present, and a problem concerning chemical stability, such as oxidation, Or more. Therefore, the powder having magnetic properties preferably has an average particle diameter of 1 to 100 m, more preferably 2 to 50 m, more preferably 3 to 25 m, Particularly preferred. In the present specification, the " average particle diameter " of the powdered particle means a particle diameter (median diameter D ₅₀ ) corresponding to an integrated value of 50% by volume in the particle size distribution of the powdery particles measured using a laser diffraction scattering type particle size distribution measurement apparatus, .

The manufacturing method for forming the molded body portion (compacted core 3) is not limited. The raw material for forming the molded part (compacted cored core 3) (the " raw material " in this specification means raw material for forming the compacted part (compacted core 3)) contains the binder , And the fine particles having magnetic properties in proximity to each other may be bound to each other by a component derived from this binder or binder (in the present specification, these may be collectively referred to as " binder-based component "

Specific examples of the binder include organic materials such as epoxy resin, silicone resin, silicone rubber, phenol resin, urea resin, melamine resin, PVA (polyvinyl alcohol) and acrylic resin, ₂ O-SiO ₂ ), oxide glass powder (Na ₂ OB ₂ O ₃ -SiO ₂ , PbO-B ₂ O ₃ -SiO ₂ , PbO-BaO-SiO ₂ , Na ₂ OB ₂ O ₃ -ZnO, CaO- SiO ₂ , Al ₂ O _3, B ₂ O ₃ -SiO ₂ , B ₂ O ₃ -SiO ₂ ), glassy materials (SiO ₂ , Al ₂ O ₃ , ZrO ₂ , TiO _2, etc. produced by the sol- And the like), and the like. The binder may be a mixture of an organic material and an inorganic material. The binder may be composed of one kind of material or may be a mixture of a plurality of materials.

When the raw material contains a binder, the content thereof is not limited. And the molded body portion (compacted core 3) may be properly set so as to have desired characteristics.

The raw material may contain zinc stearate, aluminum stearate or the like as a lubricant for the purpose of adjusting the fluidity of the magnetic powder. When the raw material contains a lubricant, its content is not limited. And the molded body portion (compacted core 3) may be properly set so as to have desired characteristics.

3. Porosity

The molded part (compacted cored core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention may preferably have a porosity of 5 vol% or more and 30 vol% or less as defined below.

In the present specification, the porosity (unit:%) means the percentage of the volume of the void portion defined as the portion in which the solid material does not exist in the molded body portion (compacted core 3) with respect to the volume of the entire molded body portion . The solid material constituting the compacted part (compacted cored core 3) contains powdered particles having magnetism. When the raw material contains a component other than the powder having a magnetic property such as the binder, the binder component is also included in the solid material.

The method of deriving the porosity is not limited. The porosity may be derived based on the composition of the compacted part (compacted cored core 3) and the measurement result of the shape of the compacted body. Alternatively, the porosity may be derived on the basis of the result of observing the surface of the compacted body (compacted cored core 3), the wavefront, the cross section, and the like.

(Porosity core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention can be improved by adjusting the porosity to 5 volume% or more and 30 volume% or less The reason why there is such a case is unclear. The higher the porosity is, the higher the magnetic properties such as the magnetic permeability and the core loss in the molded body portion (compacted core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention tend to be improved (Internal stress caused by pressurization at the time of molding and internal stress caused by magnetostriction) generated in the powder compact having magnetic properties in the molded body portion can be reduced There is a possibility that In addition, when the porosity is high, the insulating property of the compacted part (compacted cored core 3) tends to be lowered.

The porosity of the molded part (compacted cored core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention is preferably 10 vol% or more and 28 vol% or less, more preferably 12 vol% or more and 27 vol% , And particularly preferably from 15 vol% to 26 vol%. If the porosity is excessively high, the mechanical strength of the compacted part (compacted cored core 3) may tend to decrease.

4. Pore parameters (P1)

In the present specification, the "pore parameter (P1)" is defined by the following formula (1). The pore parameter P1 is a parameter indicating how much void portion exists in a region other than the region occupied by the molded body portion after molding, that is, the region occupied by the powdered body having magnetism in the molded product.

P1 = Rv / (Rv + Rb) (1)

Here, Rv (unit: volume%) represents the porosity (of the molded product) after the forming process in the molded part (green compact core 3) of the electronic component (inductance element 1) according to one embodiment of the present invention to be. Rb (unit: volume%) is the ratio of the binder component (of the molded product) after molding to the molded part (compacted core 3) in the electronic component (inductance element 1) according to the embodiment of the present invention (Hereinafter, this volume ratio is also referred to as " binder content "). Even when a heat treatment such as a variation in the composition of the binder system component is performed on the molded part (molded product) after the molding process, the void parameter (Rb) calculated using the binder content Rb in the pre- It is possible to define the characteristics of the electronic component (inductance element 1) and the molded body portion (compacted core 3) according to the embodiment of the present invention. In addition, the molded part (compacted cored core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention does not need to be subjected to a special heat treatment for the molded product after the molding process.

The method of obtaining the binder content is not limited. When the composition of the compacted part (compacted cored core 3) is clear, the content of the binder can be obtained from the information based on the composition and the measurement result of the volume. Even if the composition of the molded body portion (compacted core 3) is not clear, the binder system component is removed from the molded body portion (compacted core 3) by means such as heating, and based on the mass change at that time It is possible to obtain the binder content.

In the electronic component (inductance element 1) according to the embodiment of the present invention, the pore parameter P1 based on the above definition is 0.3 or more and 0.8 or less. The porosity parameter P1 is not less than 0.3, it is possible to improve the magnetic properties and insulation of the molded body portion (compacted core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention. From the viewpoint of more stably improving the magnetic properties and insulating properties of the molded body portion (compacted core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention, the pore parameter P1 is 0.45 or more There are cases where it is preferable, and the case of 0.5 or more is more preferable, the case of 0.55 or more is more preferable, and the case of being 0.6 or more is particularly preferable. The porosity parameter P1 is 0.8 or less and it is possible to suppress the remarkable deterioration of the mechanical properties and insulation of the molded part (compacted powder core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention have. From the viewpoint of appropriately ensuring the mechanical characteristics (strength) of the molded body portion (compacted core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention, the pore parameter P1 is preferably 0.75 or less There is a case where it is preferable that it is 0.7 or less.

The pore parameter P1 of the compacted body portion (compacted core 3) can be approximated to have a proportional relationship with the powdery determination ratio calculated based on the surface observation of the molded body portion (compacted cored core 3). When the void parameter P1 is increased, the possibility that the binder system component exists in a region other than the region occupied by the powdered magnetic material in the molded body portion (compacted core 3) is reduced. Therefore, it is considered that the powder having magnetic properties is likely to be exposed, and the probability that the powdered material having magnetism is observed when the molded body portion (compacted powder core 3) is observed on the surface is increased.

5. Magnetic properties

The electronic component according to an embodiment of the present invention may be an inductance element. In the case where the electronic component according to the embodiment of the present invention is an inductance element (a specific example is the inductance element 1), the core (specifically, the pressor core 3) provided in the inductance element has a frequency of 100 kHz Permeability of 20 or more. It is also preferable that the core loss measured at a frequency of 100 kHz and a maximum magnetic flux density of 100 mT is 1500 kW / m 3 or less. Alternatively, the core loss measured under the conditions of 100 kHz and the maximum magnetic flux density of 50 mT is preferably 120 kW / m 3 or less. Since the core has such a magnetic characteristic, the electronic part according to the embodiment of the present invention can effectively function as an inductance element. From the viewpoint of enabling the electronic part according to the embodiment of the present invention to function more effectively as the inductance element, the core of the inductance element preferably has a relative permeability of 22 or more at a frequency of 100 MHz, Or more. From the same viewpoint, the core loss of the core of the inductance element measured at a frequency of 100 kHz and a maximum magnetic flux density of 100 mT is preferably 1500 kW / m 3 or less, and particularly preferably 800 kW / m 3 or less. Alternatively, the core included in the inductance element preferably has a core loss of 100 kW / m 3 or less and a specific resistance of 90 kW / m 3 or less as measured at a frequency of 100 kHz and a maximum magnetic flux density of 50 mT.

6. Shape, electrical characteristics

An electronic component according to an embodiment of the present invention has a terminal-to-terminal distance of 4 mm or less. As the distance between the terminals decreases, the DC resistance (insulation resistance) of the molded body portion located between the terminals tends to decrease. If this resistance value is lowered, there is a high possibility that it affects the characteristics required for the electronic component. For example, when the electronic component is an inductance element, the DC resistance (insulation resistance) of the molded part (core) is lowered, thereby making it difficult to achieve the functions required for the inductance element such as noise suppression, rectification, . However, in the electronic component (inductance element 1) according to the embodiment of the present invention, when the void parameter P1 of the molded part (core 3) falls within the above-mentioned range, (Core 3) is excellent. Therefore, the electronic component (inductance element 1) according to the embodiment of the present invention can appropriately fulfill required functions even when the size is small.

The inter-terminal distance of the electronic component (inductance element 1) according to the embodiment of the present invention may be 3 mm or less, or 2 mm or less. The lower limit of the terminal-to-terminal distance of the electronic component (inductance element 1) according to the embodiment of the present invention is not limited. The distance between the terminals is preferably 100 占 퐉 or more, more preferably 500 占 퐉 or more, and particularly preferably 1 mm or more.

In the present specification, the specific resistance of the molded body portion is calculated on the basis of a resistance value measured by applying a DC voltage of 15 V to a member made of the same material as that of the molded body portion with a distance between measuring electrodes of 2 to 4 mm Value (unit: k [Omega] m or M [Omega] m). Since the electronic component is usually driven at about several volts to about 10 volts, about 15 volts is suitable as an applied voltage for evaluating the insulation property.

The resistivity of the molded body portion (compacted core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention is preferably 10 k? M or more, more preferably 15 k? M or more, K? M or more.

The resistivity of the molded part (compacted powder core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention is determined by the particle size of the powdered powder having magnetic properties contained in the molded part (compacted powder core 3) Can be changed by adjusting the distribution. For example, in the case of having the particle size distribution represented by the following formula (2), the resistivity can be increased. It is considered that the smaller the P2 represented by the following formula (2) is, the narrower the distribution width of the particle diameter with respect to the average particle diameter, and the lower the degree of contact between the powder particles having magnetic properties.

_{P2 = (D 90 - D 10} ) / D 50 ≤ 2.0 (2)

Here, D ₁₀ , D ₅₀ and D ₉₀ are respectively the particle diameters corresponding to the integrated value (cumulative frequency) of 10% by volume in the particle size distribution of the powder particles measured using the laser diffraction scattering particle size distribution measuring apparatus (Unit: mu m), a particle diameter (unit: mu m, that is, an average particle diameter) corresponding to an integrated value of 50 vol% and a particle diameter (unit: mu m) corresponding to an integrated value of 90 volume%.

From the viewpoint of enhancing the resistivity, P2 represented by the above formula (2) is preferably 1.7 or less, more preferably 1.5 or less, particularly preferably 1.3 or less. As P2 is lowered, the resistivity may be remarkably increased. Specifically, it may be about 1 GΩ · m or more.

7. Control method of machine characteristics

The method of controlling the porosity and the pore parameter P1 of the molded body portion (compacted core 3) of the electronic component (inductance element 1) according to the embodiment of the present invention is not limited. The porosity or the pore parameter P1 can be controlled by changing the manufacturing process of the molded body portion (compacted core 3).

Hereinafter, a case where the compacted body portion (compacted powder core 3) is produced by a manufacturing method including a step of press-molding a raw material containing a magnetic powder and a binder is taken as a specific example, (3)) or the air gap parameter (P1) through the manufacturing process will be described.

As one of the above control methods, there can be mentioned a method of changing the composition of the binder contained in the raw material and the content of the binder in the raw material. By varying these, the porosity and the pore parameter P1 of the molded part (compacted cored core 3) can be changed by influencing the content and properties of the binder-based component of the molded product obtained from the raw material. According to this method, by increasing the content of the binder in the raw material, it is possible to lower the porosity and the pore parameter (P1). However, the specific numerical values of the porosity and the pore parameter P1 and the degree of the change vary depending on the kind of the binder and other factors.

As another control method of the above-described control method, after the raw material is pressure-formed, the removal of the binder-based component, that is, a part of the binder-based component is performed to remove the porosity of the compacted part (compacted cored core 3) Change. According to this method, when the porosity is increased, the content of the binder system component in the molded body portion (compacted core 3) is relatively reduced, and the void parameter P1 is increased.

Examples of the removal treatment include a heat treatment, a dissolution treatment, and a decomposition treatment by irradiation of an energy ray.

In the case of carrying out the removal treatment by the heat treatment, the thermal properties of the binder (specific examples include thermoplastic, thermosetting, and composite properties obtained by mixing materials of these properties), and the decomposition temperature of the binder And the like are suitably set. The conditions (heating temperature, heating time, etc.) of the heat treatment are not limited as long as the removal of the binder component is possible. When the molded product is subjected to heat treatment to obtain a molded part (compacted cored core 3) for the purpose of alleviating the stress of the magnetic powder contained in the molded product obtained by press molding the raw material, From the viewpoint of increasing the production efficiency, it is preferable that the heat treatment, which is a kind of the removal treatment, is performed by performing the heat treatment. In the case where the removing treatment is carried out by the heat treatment, the binder system component contained in the molded body portion (compacted core 3) may contain a heated residue of the binder.

As a specific example of the case where the removal treatment is performed by the dissolution treatment, the molded product may be brought into contact with a liquid capable of dissolving the binder system component. Examples of the contact method include immersion and spraying.

As a concrete example of the removal treatment by decomposition treatment by irradiation of an energy ray, irradiation of a molded product with a microwave, an ultraviolet ray, an X-ray, an electron beam, a laser or the like is exemplified. Infrared irradiation may have substantially the same effect as the heat treatment described above.

As another example of the above control method, there can be mentioned a method of changing the porosity or the pore parameter P1 of the compacted part (compacted cored core 3) by changing the production conditions of the compacted body constituting the compacted body part. Concretely, examples of the conditions include pressurizing conditions (pressing force, pressing time and the like), heating conditions (heating temperature, heating time, etc.) when heat treatment is additionally performed.

In controlling the porosity or the pore parameter P1 of the molded body portion (compacted core 3), the above method may be used alone, or a plurality of methods (including methods other than the above methods) may be combined.

8. Electronic parts

An electronic apparatus according to an embodiment of the present invention is one in which an electronic component (inductance element 1) according to an embodiment of the present invention is mounted. The electronic parts (inductance element 1) according to the embodiment of the present invention do not deteriorate in mechanical properties and insulation properties of the molded part (compacted powder core 3) even if the size is small, , Problems such as breakage do not occur well when manufacturing them as electronic parts, when they are mounted on electronic devices, and when they are used as electronic devices, and the problem of insulation breakdown does not occur well. Therefore, the electronic apparatus mounted with the electronic component according to the present invention mounts the electronic component with the small size, so that it is possible to downsize and lighten the electronic apparatus. In addition, even when the device is miniaturized and lightened as such, defects derived from electronic parts are not generated well, and operation stability is excellent.

The above-described embodiments are described for the purpose of facilitating understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design modifications and equivalents falling within the technical scope of the present invention.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to these Examples and the like.

Example 1

(Example 1-1)

The amorphous soft magnetic powder was weighed so as to have 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%} using a water _atomization method 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 apparatus MT3300EX" manufactured by Nikkiso Co., Ltd. As a result, the average particle diameter (D50) was 10.6 mu m.

100 parts by mass of the above soft magnetic powder, 2 parts by mass of a binder containing a resin-based material containing a novolac epoxy resin, and 0.3 part by mass of a lubricant of zinc stearate were mixed in water as a solvent to obtain a slurry as a raw material for the core .

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

The granulated powder obtained by the above method was charged into a mold and subjected to pressure molding under the condition that the mold temperature was 150 캜 and the surface pressure was 25 MPa for 35 minutes. After depressurization, the molded article was maintained at 150 캜 for 5 hours to obtain a molded product.

The obtained molded product was placed in a furnace in a nitrogen gas flow atmosphere and the furnace temperature was heated from room temperature (23 DEG C) to 372 DEG C at a heating rate of 40 DEG C / min. Thereafter, heat treatment was performed to cool it to room temperature in the furnace. Thus, an annular core having an outer diameter of 20 mm, an inner diameter of 12 mm, and a thickness of 4 mm was obtained.

(Examples 1-2 to 1-5)

The same manufacturing method as in Example 1-1, but the production method in which the blending amount of the binder in the slurry preparation of Example 1-1 was changed as follows, And a porosity and a pore parameter (P1) were different from that of the core.

Example 1-2: 3 parts by mass

Example 1-3: 4 parts by mass

Example 1-4: 5 parts by mass

Example 1-5: 6 parts by mass

The porosity (Rv) (unit:%) of each of the cores prepared in the examples was calculated from the volume (V) of the core, the density (rho 1) and the mass (m1) of the soft magnetic powder, And the density (rho 2) and the mass (m < 2 >) of the binder system component.

Rv = {1 - (m1 /? 1 + m2 /? 2) / V} 100

In the above calculations, it was assumed that the lubricant was entirely volatilized during the heat treatment.

The volume content (Rb) (unit:%) of the binder system component was calculated on the basis of the following equation for the core produced in Example 1, similarly to the above porosity (Rv).

Rb = (m2 / rho2) / Vx100

The void parameter (P1) was calculated on the basis of the following equation using the volume ratio (Rb) and the void ratio (Rv) occupied by the binder system component.

P1 = Rv / (Rv + Rb)

The pore parameter P1 indicates the ratio of the void portion to the portion other than the region occupied by the soft magnetic powder in the core which is the molded body portion after the molding process.

Example 2

(Example 2-1)

100 parts by mass of the soft magnetic powder prepared in the same manner as in Example 1, 2 parts by mass of a binder containing a resin material containing an acrylic resin as a thermoplastic resin and a phenolic resin as a thermosetting resin, and 0.3 parts by mass of a lubricant of zinc stearate Was mixed with water as a solvent to obtain a slurry as a raw material of the core.

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

The granulated powder obtained by the above method was filled in a metal mold and subjected to pressure molding under conditions of a mold temperature of 23 캜 and a surface pressure of 1.5 가, thereby obtaining a molded product.

The obtained molded product was placed in a furnace in an atmosphere of nitrogen gas flow and the furnace temperature was heated from room temperature (23 캜) to 372 캜 at a temperature raising rate of 40 캜 / min, maintained at this temperature for 60 minutes, Heat treatment was performed so as to cool to room temperature. Thus, an annular core having an outer diameter of 20 mm, an inner diameter of 12 mm, and a thickness of 2 mm was obtained. The obtained core contained a heated residue of the binder as a binder system component.

(Examples 2-2 to 2-13)

The same manufacturing method as in Example 2-1, but by carrying out the production method in which at least one of changing the content of the binder in the slurry as the raw material, changing the composition of the binder, and changing the molding surface pressure, 2, a core having a porosity different from that of the core prepared in Example 2-1 was produced.

Hereinafter, the points of change in the production conditions in the respective Examples are summarized.

Examples 2-2 to 2-4: The content of the binder in Example 2-1 was changed.

Examples 2-5 to 2-7: The binder composition was changed for each of Examples 2-2 to 2-4.

Example 2-8: The molding surface pressure of Example 2-1 was changed.

Examples 2-9 and 2-10: The content of the binders of Examples 2-8 was changed.

Examples 2-11 to 2-15: For each of Examples 2-8, the composition of the binder was changed (Example 2-14 was the same condition as Example 2-8).

Examples 2-16 to 2-19: The thermoplastic resin species contained in the binder were changed for each of Examples 2-12 to 2-15.

Example 2-20: The binder was changed to a binder made of a thermoplastic resin of the kind used in Examples 2-16 to 2-19.

(Example 3-1)

100 parts by mass of a soft magnetic powder composed of an amorphous soft magnetic powder prepared so as to have an average particle size of 5 to 6 占 퐉 as in Example 1, 70 parts by mass of an acrylic resin as a thermoplastic resin and 30 parts by mass of a phenolic resin as a thermosetting resin , 2 parts by mass of a binder containing a resin-based material and 0.3 parts by mass of a lubricant composed of zinc stearate were mixed with water as a solvent to obtain a slurry as a raw material for the core.

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

The granules obtained by the above method were filled in a mold and subjected to pressure molding under the conditions of a mold temperature of 23 캜 and a surface pressure of 1 가, thereby obtaining a molded product. In this embodiment, the pore parameter P1 of the molded product (core before heat treatment) was calculated as the molded article after molding.

The obtained molded product was placed in a furnace in an atmosphere of a nitrogen gas stream and the furnace temperature was heated from room temperature (23 DEG C) to 372 DEG C at a heating rate of 40 DEG C / min, maintained at this temperature for 17 minutes, Heat treatment was performed so as to cool to room temperature. Thus, an annular core having an outer diameter of 20 mm, an inner diameter of 12.7 mm, and a thickness of 3 mm was obtained. The binder-based component of the obtained core contained heated residue of the binder.

(Examples 3-2 to 3-5)

The same manufacturing method as in Example 3-1 was carried out but the production method of changing the binder content in the slurry as the raw material was carried out so that the porosity and the porosity of the core prepared in Example 3-1 The cores with different pore parameters (P1) were prepared.

(Test Example 1) Derivation of specific resistance

The resistivity (unit: k [Omega] m or M [Omega] m) was calculated on the basis of the resistance value measured by applying a direct current voltage of 15 V to the thickness direction (2 to 4 mm) of the core produced by the example. The calculation results are shown in Tables 1 to 3. Fig. 3 shows the relationship between the specific resistance and porosity obtained from Table 1. Fig. 7 shows the relationship between the relative values (the relative value of the resistivity) and the pore parameter P1 obtained by normalizing the values of the other resistances of the present embodiment by the maximum values of the resistivity obtained in the respective embodiments.

(Test Example 2) Measurement of magnetic properties

The non-magnetic permeability (unit: dimensionless) at a frequency of 100 kHz was measured using an impedance analyzer ("4192A" manufactured by HP Corporation) for the core manufactured by the example, and measured by a BH analyzer (Unit: kW / m < 3 >) under the conditions of a frequency of 100 kHz, a maximum magnetic flux density of 100 mT (Examples 1 and 2) or 50 mT (Example 3). The results of these measurements are shown in Tables 1 to 3. The relation between the specific permeability and porosity obtained from the measurement results of Table 1 is shown in Fig. 4, and the relationship between the core loss and porosity obtained from the measurement results of Table 1 is shown in Fig. The relation between the specific permeability and the pore parameter (P1) obtained from the measurement results of Table 1 and Table 3 is shown in Fig. For Examples 1 and 3, the relationship between the relative value (the relative value of the core loss) obtained by normalizing the values of the other core losses of this embodiment and the pore parameter P1 by the maximum values of the core losses obtained in the respective Examples is shown in Fig. 9 Respectively.

(Test Example 3) Measurement of the pressing strength

The cores produced in Examples 1 and 3 were measured by a test method according to JIS Z 2507: 2000 to determine the pressing strength (unit: N / mm 2). Table 1 shows the obtained pressing strength. The relationship between the pressing strength and the porosity shown in Table 1 is shown in Fig. Fig. 10 shows the relationship between the pressing strength and the pore parameter P1 shown in Tables 1 and 3.

[Table 1]

[Table 2]

[Table 3]

(Test Example 4) Particle size distribution of soft magnetic powder

The soft magnetic powder composed of the amorphous soft magnetic powder and the soft magnetic powder used in Example 3 were produced in the same manner as the amorphous soft magnetic powder used in Example 1, And the particle size distribution was measured by volume distribution using a measuring device MT3300EX. Fig. 11 shows the relationship between the cumulative frequency (integrated value) and the grain size of the soft magnetic powder in each example. Table 4 shows D ₁₀ , D ₅₀ and D ₉₀ obtained from these measurements and P2 calculated based on the above formula (2).

[Table 4]

(Test Example 5) Observation of core surface and measurement of powder determination rate

The surfaces of the cores prepared in Examples 1 and 3 were observed with a secondary electron microscope at an accelerating voltage of 1.5 kV at a magnification of 3,000 times in a state after the forming process (a state before heat treatment for Example 3) Respectively. An image processing software ("XG Vision Editor (4.2.0041)" manufactured by KEYENCE CORPORATION) that obtains the area ratio of the powder in the image as a determination rate (unit:%) by performing the outline detection of the powder is automatically analyzed Mode. As a result of plotting the relationship between the obtained result (determination ratio) and the pore parameter P1, it was possible to approximate it in a proportional relationship, and its proportional coefficient was 54 (FIG. 12).

From Example 1, the following findings were obtained.

It is possible to control electrical, magnetic and mechanical properties of the core by varying porosity (Table 1 and Figures 3 to 6).

By setting the porosity to 30% or less, the specific resistance of the core can be made 10 k? M or more (Table 1 and Fig. 3).

By setting the porosity to 5% or more, the specific permeability of the core can be 20 or more (Table 1 and Fig. 4).

When the pore parameter P1 is small, that is, when the ratio of the void portion in the region other than the soft magnetic powder of the core is small, the pressing strength is strengthened and the resistivity is improved, but the core loss and the specific permeability are deteriorated , It is effective to adjust these pore parameters P1 to balance them.

From Example 2, the following findings were obtained.

The electrical and magnetic properties of the core can be controlled by adjusting the porosity by varying various factors in the manufacturing process (Table 2).

From Examples 1 and 3, the following findings were obtained.

It is possible to control the electrical, magnetic and mechanical properties of the core by varying the pore parameter Pl (Table 3 and Figures 7 to 10).

By setting the pore parameter P1 to 0.3 or more, the specific permeability of the core can be made to be 20 or more (Table 3 and Fig. 8).

By setting the pore parameter P1 to 0.8 or less, more preferably 0.75 or less, the pressing strength of the core can be made 7 MPa or more. More preferably, by setting the pore parameter P1 to 0.7 or less, the pressing strength of the core can be 15 MPa or more (Table 3 and Fig. 10).

By setting the pore parameter P1 to 0.3 or more, the specific resistance and core loss can be reduced. The pore parameter P1 is 0.45 or more, preferably 0.5 or more, more preferably 0.55 or more, If it is set to 0.6 or more, it is possible to lower the resistivity and the core loss more stably (Table 3 and Figs. 7 and 9). There is a possibility that the threshold value of whether or not the specific resistance and core loss in the pore parameter P1 are reduced is influenced by the composition of the binder system component contained in the core.

The following findings were also obtained.

By changing the particle size distribution of the soft magnetic powder, the value of the resistivity can be changed (Tables 1, 3, 4 and 11). Specifically, by using the soft magnetic powder having a relatively narrow particle size distribution width, the value of the resistivity can be remarkably increased.

The powder determination ratio obtained by observing the surface of the core after the shaping of the core and detecting the outline of the powder is proportional to the pore parameter P1 (FIG. 12). Therefore, when the powder determination ratio is in the range of 15% to 50% based on the range of 0.3 to 0.8 which is a preferable range of the pore parameter P1, it is possible to obtain a core having excellent electrical characteristics, It is possible.

The electronic component of the present invention is preferable as an inductance element used in a power supply circuit such as a cellular phone, a smart phone, and a notebook PC.

1: inductance element
2: Coils of common core (coil)
3:
4: Terminal portion
10: mounting board
12: solder layer
40: connection end (welded portion)
42a: first curved portion (solder joint portion)
42b: second bending portion (solder joint portion)

Claims (10)

1. An electronic component having a portion composed of a powdered body having magnetism and a molded body containing a binder system component and having a terminal-to-terminal distance of 4 mm or less,
Wherein a void parameter (P1) defined by the following formula (1) in a portion formed of said molded product is 0.3 or more and 0.8 or less.
P1 = Rv / (Rv + Rb) (1)
Here, Rv (unit: volume%) is a porosity after molding of the portion formed of the molded product, and Rb (unit: volume%) is a volume ratio of the binder component after the molding process . The method according to claim 1,
The distance between the measuring electrodes is set to 2 to 4 mm and a direct current voltage of 15 V is applied to the member made of the same material as the portion made of the molded body containing the magnetic powder having the magnetic property, Wherein the specific resistance is 10 k [Omega] m or more. 3. The method according to claim 1 or 2,
Wherein the electronic component is an inductance element having a core made of a molded body containing the powdered body having magnetic properties as a core. The method of claim 3,
Wherein a portion of the molded body has a relative permeability of 20 or more when the frequency is 100 kHz. The method of claim 3,
Wherein a portion of the molded body has a core loss of 1500 kW / m 3 or less as measured at a frequency of 100 kHz and a maximum magnetic flux density of 100 mT. The method of claim 3,
Wherein a portion of the molded body has a core loss of 120 kW / m 3 or less as measured at a frequency of 100 kHz and a maximum magnetic flux density of 50 mT. The method according to claim 1,
Wherein the part of the molded product is obtained by molding the raw material containing the magnetic powder and the binder by changing the content of the binder with respect to the raw material so that the gap parameter (P1) . The method according to claim 1,
Wherein the surface of the portion of the molded body which has been subjected to the molding process is observed with a secondary electron microscope at an observation magnification of 3,000 times at an accelerating voltage of 1.5 kV to obtain a powder judging ratio of an observed image of 15% . The method according to claim 1,
Wherein the magnetic powder having the magnetic property contained in the portion made of the molded product has a particle size distribution represented by the following formula (2).
(D ₉₀ - D ₁₀ ) / D ₅₀ ? 2.0 (2)
Here, D ₁₀ , D ₅₀ and D ₉₀ are respectively the particle diameter (unit: μm) corresponding to 10% by volume of the integrated value in the particle size distribution of the powder particles measured using the laser diffraction scattering particle size distribution measuring apparatus, (Unit: 占 퐉) corresponding to the cumulative value of 50 volume% and the particle diameter (unit: 占 퐉) corresponding to the cumulative value of 90 volume%. An electronic device in which the electronic component according to claim 1 is mounted.

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