JP3381939B2 - Ferrite sintered body, chip inductor parts, composite laminated parts and magnetic core - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ferrite sintered body used as various magnetic materials, a chip inductor using the sintered body as a magnetic material, a composite laminated component such as an LC composite component, and a magnetic core.

[0002]

2. Description of the Related Art Various ferrites are used as various magnetic core materials and composite laminated parts because of their excellent magnetic properties. The laminated LC composite component integrally includes a capacitor chip body formed by laminating a ceramic dielectric layer and an internal electrode layer, and an inductor chip body formed by laminating a ferrite magnetic layer and an internal conductor. It was done. Such composite laminated components are widely used in various electronic devices because of their small volume, high robustness and high reliability.

These components, for example, LC composite components, are usually formed by laminating the internal conductor paste, the magnetic layer paste, the dielectric layer paste and the internal electrode layer paste by a thick film technique and then firing them. It is manufactured by printing or transferring an external electrode paste on the surface of the obtained sintered body and then firing it. In this case, the magnetic material used for the magnetic layer is Ni because it can be fired at a low temperature.
-Cu-Zn type ferrite and Ni-Zn type ferrite are generally used.

Also, some attempts have been proposed to add glass to such ferrite to modify its characteristics. For example, Japanese Patent Laid-Open No. 2-288307 discloses Ni
-A laminated inductor is disclosed in which a self-resonant frequency is improved by using a magnetic material obtained by adding 20 to 30% by weight of borosilicate glass to ferrite.

Further, Japanese Patent Laid-Open No. 1-31823 discloses that
An inductor component and a method for manufacturing the same are disclosed, in which a mixture of metal magnetic powder and low melting point glass powder is pressure-molded. Further, in Japanese Patent Application Laid-Open No. 1-110708, a ferrite sintered body, a chip inductor and an LC in which borosilicate glass is added in an amount of 15 to 75% by weight in order to improve the sintered density and the mechanical strength, etc. Composite parts are disclosed.

In addition, a technique is known in which glass is added to ferrite to improve various properties (Japanese Patent Laid-Open No. 51-151331, US Pat. No. 454050).
No. 0, JP-A-58-135133, JP-A-58-135606 to 135609).

Various attempts have been made so far to add glass to ferrite to modify its characteristics, but it is necessary to sufficiently improve the characteristics of μi, L and Q in the magnetic core and the chip inductor. A glass compounding system that can be used has hitherto not been known.

Therefore, as a result of intensive investigations by the inventors of the present invention to find out a glass compounding system capable of sufficiently improving such characteristics, N was used as a magnetic material for a magnetic core or a chip inductor.
It has been found that the above characteristics can be improved by using i-Cu-Zn ferrite and adding a specific glass in a specific amount range.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to set the content of a specific glass in ferrite in a ferrite sintered body within a predetermined range to keep μi, L and Q at high values. is there.

[0010]

The above objects are achieved by the present invention described in (1) to (6) below. (1) A ferrite sintered body containing two or three kinds of Ni, Cu and Zn, wherein the ferrite material in the raw material stage contains B ₂ O ₃ in a range of 50 ppm or more and less than 1000 ppm, which is lower than the sintering temperature. It added after calcination at 80
A ferrite sintered body sintered at a temperature of 0 to 930 ° C. (2) A ferrite sintered body containing two or three kinds of Ni, Cu and Zn, wherein the ferrite material in the raw material stage contains SiO ₂ : 0.1 to 15% by weight, B ₂ O ₃ :
10-40% by weight, PbO: 0.1-40% by weight, Zn
O: 20 to 70 wt% and Al ₂ O _3: 0~6 wt%
Containing glass within the range of 250 to 4000 ppm,
800 ~ by adding after calcination at a temperature lower than the sintering temperature
A ferrite sintered body sintered at a temperature of 930 ° C. (3) the composition of the ferrite is Fe ₂ O _3: 40~52mo
l%, NiO: 0 to 50 mol%, CuO: 0 to 20 mol% and ZnO: 0 to 50 mol% (1) or (2)
Ferrite sintered body. (4) A chip inductor component having an inductor portion configured by laminating a ferrite magnetic layer and an internal conductor, wherein the ferrite magnetic layer is the above (1) to (3).
A chip inductor component, characterized in that the chip inductor component is composed of any one of the above ferrite sintered bodies. (5) A composite laminated component having at least a chip inductor portion formed by laminating a ferrite magnetic layer and an internal conductor, wherein the ferrite magnetic layer is the ferrite sintered body according to any one of (1) to (3) above. A composite laminated component characterized by being composed of a body. (6) A magnetic core comprising the ferrite sintered body according to any one of (1) to (3) above.

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

In the ferrite sintered body of the present invention, B ₂ O ₃ is contained in the Ni—Cu—Zn type ferrite component in the raw material stage.
0 ppm or more and less than 1000 ppm, preferably 200 to 90
0 ppm, more preferably in the range of 400 to 800 ppm, or SiO ₂ : 0.1 to 15 wt%, preferably 3 to 12 wt%, B ₂ O ₃ : 10 to 4
0% by weight, preferably 20 to 35% by weight, PbO: 0.
1-40% by weight, preferably 3-20% by weight, ZnO:
20 to 70 wt%, preferably 45 to 65 wt% and Al ₂ O _3: 0~6 wt% of SiO ₂ -B ₂ O ₃ -Pb
O-ZnO-Al ₂ O ₃ based glass of 250-4000
It must be added in ppm, preferably in the range 1000-2000 ppm. Only when the content of these glass components is within the above range, a remarkable and critical improvement effect of the magnetic properties μi, L and Q is recognized.

In the present invention, the reason why the μi is improved by adding a predetermined amount of the specific glass is that liquid phase sintering is formed by the low melting point compound to improve the sinterability and the ferrite grains. It is considered to promote the growth from low temperature. On the other hand, the reason why the Q characteristic is improved is that the specific resistance of the ferrite sintered body is improved.
It is considered that this is because the eddy current loss during ferrite magnetic loss becomes smaller.

The ferrite used in the present invention is Ni-Cu-
Zn, Ni-Cu, Ni-Zn, and Cu-Zn are not particularly limited, and various compositions may be selected according to the purpose.
Fe ₂ O _3: 40~52mol%, particularly 45~50mol%, N
iO: 0 to 50 mol%, particularly 3 to 40 mol%, CuO: 0
20mol%, especially 5-15mol% and ZnO: 0-50mo
It is preferably within the composition range of 1%, especially 6 to 33 mol%.

If the content of Fe ₂ O ₃ is too large, α-Fe
The precipitation of ₂ O ₃ deteriorates the sinterability and lowers the specific resistance of the sintered body, which causes deterioration of μi and Q.
Not preferable. Further, in the composition of the high frequency composition region where the amount of NiO is large, the same phenomenon occurs when the amount of Fe ₂ O ₃ is too large.

In a laminated chip inductor using Ag for the internal conductor, the sintering temperature is set to about 850 to 920 ° C., so that if sufficient sinterability is not obtained, not only the magnetic properties but also the reliability are lacking, which is preferable. However, good sinterability is obtained in the above composition range. In this case, when the amount of CuO is larger than the appropriate amount range, the crystal structure of ferrite becomes non-uniform, which causes deterioration of μi and Q characteristics. Fe ₂ O ₃
When the amount and the amount of CuO are fixed, the applied frequency and magnetic characteristics of ferrite are determined by the amounts of NiO and ZnO. A composition having a large amount of ZnO and a small amount of NiO results in a high μi composition at a low frequency, while a composition having a small amount of ZnO and a large amount of NiO results in a low μi composition at a high frequency.
If the amount of ZnO exceeds the appropriate amount range, the Curie point of ferrite becomes 100 ° C. or less, which is not practically reliable, which is not preferable.

By the way, the glass used in the present invention B ₂ O ₃ or SiO ₂ —B ₂ O ₃ —PbO—ZnO—
Regarding the effect of adding Al ₂ O ₃ -based glass, the following changes can be seen depending on the composition of ferrite. That is, ZnO
In the composition region near the applied frequency of 400 KHz where the amount of NiO is large and the amount of NiO is small, the μi is remarkably improved. Further, in the composition region near the applied frequency of 1 MHz, both μi and Q are remarkably improved. Furthermore, the amount of NiO is large and the amount of ZnO is small.
In the composition around ˜70 MHz, since the original μi is small, the improvement of the μiQ product is relatively small.

Next, in relation to the ferrite composition when only B ₂ O _{3 is} added, the μiQ product is greatly improved in the composition region where the amount of ZnO is large. Therefore, ZnO of ferrite is the main component in this glass composition. That μi
It will improve the Q product.

On the other hand, SiO ₂ --B ₂ O ₃ --PbO
The following tendencies are observed in relation to the ferrite composition when the —ZnO—Al ₂ O ₃ based glass is added alone.

That is, when the SiO ₂ component in this glass exceeds an appropriate amount, the sinterability of ferrite deteriorates, and
The Q product becomes smaller. Further, if the amount of PbO component in the glass exceeds an appropriate amount, in a laminated chip inductor using Ag as a conductor, it may cause direct current resistance of the conductor, Ag diffusion, and disconnection. Further, if the content of Al ₂ O ₃ in the glass exceeds an appropriate amount, the sinterability of ferrite deteriorates and the μiQ product becomes small.

From the above, a composite laminated component having at least a ferrite chip inductor component using a ferrite sintered body satisfying the conditions of the present invention has excellent performance and can have many uses as an electronic component. It is a thing.

[0027]

Specific Structure The specific structure of the present invention will be described in detail below. FIG. 1 shows a laminated LC composite component which is a preferred embodiment of the composite laminated component of the present invention.

An example of the LC composite component 1 of the present invention shown in FIG. 1 is a capacitor chip body 2 formed by laminating a ceramic dielectric layer 21 and an internal electrode layer 25, a ferrite magnetic layer 31 and an internal conductor 35. And an inductor chip body 3 formed by stacking and are integrated, and has an external electrode 51 on the surface.

The material of the ferrite magnetic layer 31 of the inductor chip body 3 is Ni-Cu-Zn system, Ni-Cu.
System, Ni-Zn system or Cu-Zn system ferrite is used. In addition, Co, Mn, etc. may be contained in an amount of about 5 wt% or less of the whole, and Ca, Si, Bi, V, P
b or the like may be contained in an amount of about 1 wt% or less.

In the present invention, the conductive material forming the internal conductor 35 needs to have a low resistivity in order to obtain a practical Q as an inductor. Therefore, a conductive material mainly containing Ag is used. preferable. At this time, it is preferable to use silver having a silver content of 90% by weight or more, particularly pure silver having a purity of 99.9% by weight or more. As described above, the specific resistance can be extremely reduced by using pure silver.

Inductor chip body 3 of LC composite component 1
May have a conventionally known structure, and the outer shape is usually a substantially rectangular parallelepiped shape. As shown in FIG. 1, the internal conductors 35 are usually arranged in a spiral shape in the magnetic layer 31 to form internal windings, and both ends of the internal conductors 35 are external electrodes 51,
It is connected to 51.

In such a case, the winding pattern of the inner conductor 35, that is, the shape of the closed magnetic circuit can be various patterns, and the number of turns thereof can be appropriately selected according to the application. Further, there is no limitation on the size of each part of the inductor chip body 3, and it may be appropriately selected according to the application.

The thickness of the inner conductor 35 is usually 5 to 3.
0 μm, winding pitch is usually 10 to 400 μm,
The number of turns is usually about 1.5 to 50.5 turns. The base thickness of the magnetic layer 31 is usually about 100 to 500 μm, and the magnetic layer thickness between the inner conductors 35 is usually 10 to 10 μm.
It is about 0 μm.

There are no particular restrictions on the ceramic dielectric layer 21 of the capacitor chip body 2, and various dielectric materials may be used. However, since the firing temperature is low, it is preferable to use a titanium oxide-based dielectric. In addition, a titanic acid-based composite oxide, a zirconic acid-based composite oxide, or a mixture thereof can also be used. Further, glass such as borosilicate glass may be contained in order to lower the firing temperature.

Specifically, as the titanium oxide-based material, NiO, CuO, Mn ₃ O ₄ , Al ₂ O ₃ and Mg may be used if necessary.
O, SiO _{2 and the} like, particularly TiO _{2 and the} like containing CuO, and BaTiO ₃ and SrTiO ₃ as titanic acid-based composite oxides.
₃ , CaTiO ₃ , MgTiO ₃ and mixtures of these,
Zirconic acid-based composite oxides include BaZrO ₃ , Sr.
Examples thereof include ZrO ₃ , CaZrO ₃ , MgZrO _3, and mixtures thereof.

In the present invention, the conductive material forming the internal electrode layer 25 is not particularly limited, and Ag, Pt, Pd, Au,
Cu, Ni, Ag-Pd alloy, etc.
It may be selected from alloys containing more than one kind, but especially A
g, Ag alloys such as Ag-Pd alloys, and the like are preferable.

Capacitor chip body 2 of LC composite component 1
May have a conventionally known structure, and the outer shape is usually a substantially rectangular parallelepiped shape. Then, as shown in FIG. 1, one end of the internal electrode layer 25 is connected to the external electrode 51.

The size of each part of the capacitor chip body 2 is not particularly limited and may be appropriately selected according to the application. The number of stacked dielectric layers 21 may be determined according to the purpose, but is usually about 1 to 100. The thickness of each dielectric layer 21 is usually about 20 to 150 μm, and the thickness of each internal electrode layer 25 is usually 5 to 3 μm.
It is about 0 μm.

There is no particular limitation on the conductive material forming the external electrode 51 of the LC composite component 1 of the present invention.
It may be selected from alloys containing at least one of t, Pd, Au, Cu, Ni, Ag—Pd alloy, and the like.
Particularly, Ag alloys such as Ag and Ag-Pd alloys are suitable. The shape and size of the external electrode 51 are not particularly limited and may be appropriately determined according to the purpose and application, but the thickness is usually about 100 to 2500 μm.

The size of the LC composite component 1 of the present invention is not particularly limited and may be appropriately selected according to the purpose and application, but is usually (1.6 to 10.0 mm) × (0.8 to 15). .0
mm) × (1.0 to 5.0 mm). The composite laminated component of the present invention is not limited to the above-described LC composite component, and may be various other composite laminated components as long as it partially has the above-described configuration.

The composite laminated component such as the LC composite component 1 of the present invention can be manufactured by a usual printing method or a sheet method using a paste.

The ferrite magnetic layer paste is prepared as follows.

First, a raw material powder of ferrite, for example, Ni
Various powders of O, ZnO, CuO, Fe ₂ O _{3 and the} like are wet-mixed in a predetermined amount by a ball mill or the like. The thus wet-mixed product is usually dried by a spray dryer and then calcined. A predetermined amount of B ₂ O ₃ or SiO ₂ —B ₂ O ₃ —PbO—ZnO—Al ₂ O ₃ type glass was added to the obtained calcined material, and this was usually ball milled to a powder particle size of 0. Wet-pulverize to a particle size of about 0.01 to 0.5 μm and dry with a spray dryer.

The obtained ferrite powder is kneaded with a binder such as ethyl cellulose and a solvent such as terpineol and butyl carbitol to form a paste. B ₂ O
_{If 3} or glass is added before calcination, its components are likely to evaporate, so it is added after calcination.

There is no particular limitation on the structure of the ceramic dielectric layer paste, and various dielectric materials or raw material powders that become a dielectric by firing are selected according to the composition of the ferrite dielectric layer as described above, and various binders and It may be prepared by kneading with a solvent.

As the raw material powder, it is usually sufficient to use an oxide constituting a titanium oxide-based or titanic acid-based composite oxide, and Ti, B or the like depending on the composition of the corresponding oxide dielectric.
Oxides such as a, Sr, Ca and Zr may be used. Further, as these, compounds which become oxides upon firing, such as carbonates, sulfates, nitrates, oxalates, and organometallic compounds may be used.

As these raw material powders, those having an average particle diameter of about 0.1 to 5 μm are usually used.

If necessary, various glasses may be contained.

If necessary, various glasses or oxides may be contained as a sintering aid or the like.

The internal conductor paste, the internal electrode layer paste, and the external electrode paste are each of the above-mentioned various conductive metals, alloys, or various oxides, organometallic compounds, and resinates that become the above-mentioned conductive material after firing. Etc. and the above-mentioned various binders and solvents are kneaded to prepare.

The content of the binder and the solvent in each of the above-mentioned pastes is not particularly limited, and the usual content, for example,
The binder may be about 1 to 5 wt% and the solvent may be about 10 to 50 wt%. In addition, each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators and the like, if necessary. The total content of these is
It is preferably 10 wt% or less.

In manufacturing the LC composite component 1, for example, first, a magnetic layer paste and an internal conductor paste are laminated and printed on a substrate such as PET.

A green sheet is formed by using the magnetic layer paste or the dielectric layer paste, the internal conductor paste and the internal electrode layer paste are printed on the green sheet, and these are laminated to form a green chip. You may form. In this case, the dielectric layer adjacent to the magnetic layer may be directly printed.

Next, the external electrode paste is printed or transferred onto the green chip, and the magnetic layer paste, the internal conductor paste, the dielectric layer paste, the internal electrode layer paste and the external electrode paste are simultaneously fired.

Alternatively, the chip body may be fired first, and then the external electrode paste may be printed and fired.

The firing temperature is 800 to 930 ° C., especially 85.
The temperature is preferably 0 to 900 ° C. The firing time is preferably 0.05 to 5 hours, particularly 0.1 to 3 hours. The firing is performed with PO ₂ = 1 to 100%.

The baking temperature for baking the external electrodes is usually about 500 to 700 ° C., and the baking time is usually 10
It is about 3 minutes to 3 hours, and firing is usually performed in air.

In the present invention, it is preferable to perform the heat treatment during and after firing in an atmosphere containing oxygen in excess of the air.

By heat-treating in an oxygen-excess atmosphere, a substance such as a metal such as Cu or Zn or an oxide having a low resistance such as Cu ₂ O or Zn ₂ O or a substance that has been deposited is converted into CuO, It can be deposited in the form of an oxide such as ZnO having a high resistance and causing no actual damage. Therefore, the circuit resistance of the component is further improved.

The heat treatment is preferably performed during the final firing and after the final firing.

For example, when the firing of the chip body and the firing for firing the external electrode are performed simultaneously, when performing the firing for firing the external electrode after firing of the chip body at the time of this firing and after this firing, It is preferable to perform a predetermined heat treatment when the external electrode is baked or after the external electrode is baked. When the firing is performed twice as in the latter case, heat treatment may be further performed when firing the chip body or after firing the chip body.

The oxygen partial pressure ratio in the heat treatment atmosphere is 20 to 1
00%, more preferably 50 to 100%, particularly preferably 100%. Below the above range, Cu, Z
The ability to suppress the precipitation of n, Cu ₂ O, ZnO, etc. decreases.

Since such heat treatment in an oxygen-excess atmosphere is usually performed at the same time as firing or external electrode baking, various conditions such as heat treatment temperature and holding time are similar to those of the baking conditions and external electrode baking conditions. However, when the heat treatment alone is performed, the heat treatment temperature is 550 to 900 ° C.
Especially, 650 to 800 ° C., holding time 0.5 to 2 hours,
It is particularly preferable to set the time to 1 to 1.5 hours.

The composite laminated parts other than the LC composite part may be manufactured as described above.

The composite laminated component of the present invention such as the LC composite component manufactured in this manner is mounted on a printed circuit board or the like by soldering the external electrodes and used for various electronic devices. .

[0066]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to specific examples of the present invention.

Examples 1 to 4, Comparative Examples 1, _{2, 3, 3} ', 4 and 4'Final composition of Fe ₂ O ₃ : 49.4 mol%, NiO: 1
6.3 mol%, CuO: 8.7 mol% and ZnO: 2
The raw materials were mixed so as to be 5.6 mol%. The raw materials are mixed by wet mixing using a ball mill, and then,
The wet mixture is dried with a spray drier,
It was calcined at 00 ° C. Add 0 to 50 B ₂ O ₃ to this calcined material
It was added in the range of 00 ppm, wet-milled with a ball mill and then dried with a spray dryer to prepare a powder having a final average particle size of 0.1 to 0.3 μm.

The obtained powder was molded into a toroidal shape. This molded product was baked in air at a firing temperature of 870 ° C for 2 hours.
The toroidal core was produced by firing for a time. The toroidal core has an outer diameter of 11.1 mm, an inner diameter of 5.1 mm, a thickness of 2.4 mm, a winding number of 20 turns, and a wire diameter of 0.35 mm.

Further, with respect to 100 parts by weight of the above powder, 3.84 parts by weight of ethyl cellulose and 78 of terpineol
A part by weight was added, and the mixture was kneaded with a triple roll to obtain a magnetic material layer paste.

Next, an internal conductor paste was prepared by adding 2.5 parts by weight of ethyl cellulose and 40 parts by weight of terpineol to 100 parts by weight of Ag having an average particle size of 0.8 μm and kneading with a three-roll mill. .

The magnetic layer paste and the internal conductor paste thus produced were printed and laminated, and various laminated and laminated types having different B ₂ O ₃ contents as shown in Table 1 were formed by the printing and laminating method. A chip inductor was manufactured.

In this case, the firing temperature was 870 ° C., the firing time was 2 hours, and the firing atmosphere was the atmosphere.

The dimensions of the obtained laminated chip inductor were 4.5 mm × 3.2 mm × 1.1 mm, and the number of turns was 9.5 turns.

Regarding these multilayer chip inductors and toroidal cores, μ was measured under the condition that the measurement frequency was 1 MHz.
i, L (μH) and Q were determined. The results obtained are shown in Table 1.
Shown in.

[0075]

[Table 1]

As can be seen from the results shown in Table 1, B ₂ O
_When the addition amount of ₃ is within the range of 50 to less than 1000 ppm, the L of the multilayer chip inductor is compared with the case of no addition.
Both the Q product and the μiQ product of the toroidal core are improved by about 25% or more. Especially, the addition amount of B ₂ O ₃ is 200 to 9
00, especially at 400 to 800 ppm, the μiQ product of the toroidal core is about 135% compared to the case without addition, and the LQ product of the multilayer chip inductor is about 35% compared to the case without addition. It has improved to over 75%.

Examples 7 to 13 and Comparative Examples 5 to 7 Fe ₂ O ₃ : 49.4 mol% and NiO: 1 in the final composition.
6.3 mol%, CuO: 8.7 mol% and ZnO: 2
The raw materials were mixed so as to be 5.6 mol%. The raw materials are mixed by wet mixing using a ball mill, and then,
The wet mixture is dried with a spray drier,
It was calcined at 00 ° C. On this calcined material, SiO ₂ : 10% by weight, B ₂ O ₃ : 25% by weight, PbO: 5% by weight, Zn
O: 59.5 wt% and Al ₂ O ₃ : 0.5 wt% glass (hereinafter, glass I) having a composition of 0 to 5000.
Add in the range of ppm, wet pulverize with a ball mill and dry with a spray dryer to obtain a final average particle size of 0.1.
A powder of ˜0.3 μm was prepared.

The obtained powder was molded into the above-mentioned toroidal shape. This molded product is baked in the air at a firing temperature of 870 ° C.
Then, it was baked for 2 hours to prepare a toroidal core. The toroidal core has an outer diameter of 11.1 mm, an inner diameter of 5.1 mm, a thickness of 2.4 mm, a winding number of 20 turns, and a wire diameter of 0.35 mm.

Also, with respect to 100 parts by weight of the above powder, 3.84 parts by weight of ethyl cellulose and 78 of terpineol
A part by weight was added, and the mixture was kneaded with a triple roll to obtain a magnetic material layer paste.

Next, an internal conductor paste was prepared by adding 2.5 parts by weight of ethyl cellulose and 40 parts by weight of terpineol to 100 parts by weight of Ag having an average particle size of 0.8 μm and kneading with a three-roll mill. .

The magnetic layer paste and the internal conductor paste thus produced were printed and laminated, and various laminated and laminated chip inductors having different glass I contents as shown in Table 2 were formed by the printed and laminated method. Was manufactured.

In this case, the firing temperature was 870 ° C., the firing time was 2 hours, and the firing atmosphere was the atmosphere.

The dimensions of the obtained laminated chip inductor were 4.5 mm × 3.2 mm × 1.1 mm, and the number of turns was 9.5 turns.

Regarding these multilayer chip inductors and toroidal cores, μ was measured under the condition that the measurement frequency was 1 MHz.
i, L (μH) and Q were determined. Table 2 shows the obtained results.
Shown in.

[0085]

[Table 2]

As can be seen from the results shown in Table 2, when the amount of the glass I added is in the range of 250 to 4000 ppm, the LQ of the multilayer chip inductor is higher than that in the case of no addition.
The product and the μiQ product of the toroidal core are both improved by about 25% or more. Especially, in the toroidal core, the amount of glass added has improved to about 140% or more in the range of 1500 to 2000 ppm, and for multilayer chip inductors, the amount of glass added has improved to about 76% or more in the range of 1000 to 1500 ppm. is doing.

Examples 14 to 17 and Comparative Examples 8 to 11 Fe ₂ O ₃ : 49.4 mol% in final composition, NiO: 1
6.3 mol%, CuO: 8.7 mol% and ZnO: 2
The raw materials were mixed so as to be 5.6 mol%. The raw materials are mixed by wet mixing using a ball mill, and then,
The wet mixture is dried with a spray drier,
It was calcined at 00 ° C. The various glasses shown in Table 3 were added to this calcined material in the range of 2000 ppm, wet pulverized with a ball mill and dried with a spray drier to obtain a powder having a final average particle diameter of 0.1 to 0.3 μm. It was made.

The compositions of comparative glasses X to XIV and glasses II to V of the present invention are shown in Table 3 below.

[0089]

[Table 3]

The obtained powder was molded into the above-mentioned toroidal shape. This molded product is baked in the air at a firing temperature of 870 ° C.
Then, it was baked for 2 hours to prepare a toroidal core. The toroidal core has an outer diameter of 11.1 mm, an inner diameter of 5.1 mm, a thickness of 2.4 mm, a winding number of 20 turns, and a wire diameter of 0.35 mm.

The shrinkage factor, sintered density and μi and Q characteristics of this toroidal core were measured under the condition of a measurement frequency of 1 MHz. The results obtained are shown in Table 4.

[0092]

[Table 4]

As can be seen from the results shown in Table 4, SiO
When _{2 -B 2 O 3 -PbO-ZnO} -Al 2 Composition of O ₃ based glass is within the scope of the present invention, .mu.i toroidal core
The Q product is improved to about 137% or more compared to the case of no addition. On the other hand, when the composition of the glass deviates from the range of the present invention, μi and Q are low because the density of the ferrite sintered body is low, and the μiQ product is smaller than that in the case where no glass is added. It's getting worse.

Examples 18 to 20 Raw materials were mixed by mixing the raw materials so that the final composition was as shown in Table 5. These raw materials were mixed by wet mixing using a ball mill, and then the wet mixture was dried by a spray dryer and calcined at 700 ° C. To this calcined material, the same glass I as that used in Example 8 was added in the range of 2000 ppm, this was wet pulverized with a ball mill and then dried with a spray dryer, and the final average particle diameter was 0.1 to 0. A 3 μm powder was prepared.

The obtained powder was molded into the above-mentioned toroidal shape. This molded product is baked in the air at a firing temperature of 870 ° C.
Then, it was baked for 2 hours to prepare a toroidal core. The toroidal core has an outer diameter of 11.1 mm, an inner diameter of 5.1 mm, a thickness of 2.4 mm, a winding number of 20 turns, and a wire diameter of 0.35 mm.

The shrinkage rate, sintered density and μi and Q characteristics of this toroidal core were determined. The measurement frequency is
The frequency was selected so that the μiQ product was the largest in each ferrite composition. The obtained results are shown in Table 6.

[0097]

[Table 5]

[0098]

[Table 6]

As can be seen from the results shown in Table 6, there is a suitable range for the ferrite composition, and Fe ₂ O ₃ : 40-5
2 mol%, NiO: 0-50 mol%, CuO: 0-20 mol%
And ZnO: within the composition range of 0 to 50 mol%, the μiQ product of the toroidal core is about 70 compared with the case of no addition.
It has improved to over%.

[0100]

The ferrite sintered body of the present invention is made of Ni-C.
u-Zn system, Ni-Cu system, Ni-Zn system, Cu-Zn
B ₂ O ₃ or SiO _{2 with a} specific composition ratio
By the addition of _{-B 2 O 3 -PbO-ZnO-} Al 2 O 3 based glass in an amount within the predetermined range, the case of using this magnetic core and multilayer chip inductor, .mu.i, inductance L and Q The composite laminated component which is held at a high value and therefore has at least such a ceramic inductor component has excellent performance and is useful for various electronic devices.

[Brief description of drawings]

FIG. 1 is a LC showing a preferred embodiment of a composite laminated component of the present invention.
It is sectional drawing which shows a composite component.

[Explanation of symbols]

1 LC composite parts 2 Capacitor chip body 21 Ceramic Dielectric Layer 25 internal electrodes 3 Inductor chip body 31 Ferrite magnetic layer 35 Inner conductor 51 External electrode

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C04B 35/30 H01F 17/00 D H01F 17/00 41/02 D 41/02 C04B 35/26 J (56) Reference JP-A-2-256204 (JP, A) JP-A-2-241008 (JP, A) JP-A-63-297239 (JP, A) JP-A-61-242928 (JP, A) JP-A-64-45771 (JP , A) JP-A-1-308844 (JP, A) JP-A-3-6803 (JP, A) JP-A-3-233908 (JP, A) JP-A-2-241007 (JP, A) JP-A 1-203241 (JP, A) Dutch Patent Publication No. 7014697 (58) Fields investigated (Int.Cl. ⁷ , DB name) H01F 1/34 C01G 49/00 C04B 35/26-35/40

Claims (6)

(57) [Claims] 1. A ferrite sintered body containing two or three kinds of Ni, Cu and Zn, wherein B ₂ O ₃ is contained in the ferrite material in the raw material stage within a range of 50 ppm or more and less than 1000 ppm, which is lower than the sintering temperature. A ferrite sintered body which is added after calcination at a low temperature and sintered at a temperature of 800 to 930 ° C. 2. A ferrite sintered body containing two or three kinds of Ni, Cu and Zn, wherein the ferrite material in the raw material stage contains SiO ₂ : 0.1 to 15 wt%, B ₂
O _3: 10 to 40 wt%, PbO: 0.1 to 40 wt%, ZnO: 20 to 70 wt% and Al ₂ O _3: 0~
A ferrite sintered body obtained by adding glass containing 6% by weight in the range of 250 to 4000 ppm after calcination at a temperature lower than the sintering temperature and sintering at a temperature of 800 to 930 ° C. 3. The composition of ferrite is Fe ₂ O ₃ : 40 to.
52 mol%, NiO: 0-50 mol%, CuO: 0-20 mo
l% and ZnO: 0 to 50 mol%.
Ferrite sintered body. 4. A chip inductor component having an inductor portion formed by laminating a ferrite magnetic layer and an internal conductor, wherein the ferrite magnetic layer is formed of the ferrite sintered body according to any one of claims 1 to 3. Chip inductor parts characterized by being 5. A composite laminated component having at least a chip inductor portion formed by laminating a ferrite magnetic layer and an internal conductor, wherein the ferrite magnetic layer is the ferrite sintered body according to any one of claims 1 to 3. A composite laminated component characterized by being composed of 6. A magnetic core comprising the ferrite sintered body according to any one of claims 1 to 3.