JP2786977B2 - Dielectric porcelain composition for low-temperature firing and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric ceramic composition for low-temperature firing and a method for producing the same, and more particularly to a low-temperature firing dielectric ceramic composition suitably used for manufacturing a dielectric resonator having an inner layer conductor such as a stripline type filter. The present invention relates to a high-frequency dielectric ceramic composition and a method for producing the same. Further, the present invention provides a dielectric resonator obtained by using such a dielectric ceramic composition or a dielectric filter composed of a plurality of the resonators, and further a dielectric resonator or a dielectric filter obtained by using the dielectric resonator. It relates to an advantageous manufacturing method.

[0002]

2. Description of the Related Art Today, coaxial dielectric filters using a high-permittivity porcelain composition are widely used in cellular phones, automobile telephones, and the like.
On the inner peripheral surface and outer peripheral surface of the cylindrical dielectric block, respectively, a plurality of coaxial resonators provided with an inner conductor and an outer conductor are coupled and configured, There is a limit to the miniaturization, and a strip line type of a triplate structure in which a conductor is provided inside a dielectric is being studied. In this stripline type filter, conductors are arranged in a predetermined pattern in a plate-shaped dielectric and provided integrally, and a structure in which a plurality of resonators are formed is employed. (Thickness) can be reduced, so that the size can be reduced.

[0003] To manufacture a dielectric filter having an inner layer conductor such as a stripline type filter, simultaneous firing of the inner layer conductor and the dielectric ceramic composition is required. Since the composition has a very high firing temperature, the composition is restricted by conductor materials that can be used as the inner layer conductor, and the composition has a low conduction resistance.
It was difficult to use g-based materials. For example, to use an Ag-Pd-based alloy or an Ag-Pt-based alloy as the inner layer conductor, the firing temperature of the dielectric ceramic composition is 1000 ° C.
In particular, in order to use Ag having a low conduction resistance alone, the firing temperature of the dielectric ceramic composition should be 90
It must be around 0 ° C. Therefore, there is a need for a dielectric ceramic composition that can be sintered at such a low firing temperature and has excellent high-frequency characteristics.

[0004] On the other hand, various types of dielectric porcelain compositions have been conventionally proposed.
A dielectric ceramic composition composed of an a-Ti-RE-Bi-based oxide (RE: rare earth metal) is a material having a high relative dielectric constant, a large unloaded Q, and a small temperature coefficient of resonance frequency. But its firing temperature is 1300
There is a problem in a high temperature range of 1 to 1400 ° C. For this reason, attempts have been made to lower the firing temperature by adding a Pb oxide or the like.

For example, in US Pat. No. 3,811,937, a calcined and ground product of barium oxide, titanium oxide and rare earth oxide is added to CdO—PbO—Bi ₂ O _3.
A composition comprising 8 to 30% by weight of a base glass has been disclosed.
The firing is performed at a temperature of about 1150C. Also, in Japanese Patent Application Laid-Open No. Sho 59-214105, Ba
For an O—TiO ₂ —Nd ₂ O ₃ based composition, PbO,
By mixing the powders of Bi ₂ O ₃ , SiO ₂ and ZnO,
Firing at a temperature between 1050 ° C and 1150 ° C has been shown. Further, Japanese Patent Application Laid-Open No. Sho 60-124306 discloses that BaTiO ₃ —Nd ₂ O ₃ —TiO ₂ —Bi ₂ O
Against ₃ based _{compositions, Pb 3 O 4, B 2} O 3, SiO
₂ , a dielectric porcelain composition comprising a predetermined amount of each of ZnO is disclosed.
It has been revealed that firing can be performed at a firing temperature of Furthermore, Japanese Patent Application Laid-Open No. 2-44609 discloses BaTiO
_{3, Nd 2 O 3, TiO} 2, Bi 2 O 3, and Pb ₃ O
The composition consisting of _{4, 2CaO · 3B 2 O 3} , S
iO _2, and the dielectric ceramic composition obtained by adding ZnO is shown, it is clear that sintered at a firing temperature of from 1,000 to 1,050 ° C..

However, even in the case of these conventional dielectric ceramic compositions which can be fired at a low temperature, the firing temperature is still as high as 1000 ° C. or higher, and Ag having a low conduction resistance is used.
A simple substance or an alloy material mainly composed of Ag cannot be used as the internal conductor. Therefore, Pd having a large conduction resistance
Is that only Ag-Pd-based alloys with an increased content of can be used. In addition, in these conventional dielectric ceramic compositions for low-temperature firing, a large amount of Pb oxide is added, and therefore there is a problem in handling the Pb oxide in view of the toxicity of the Pb oxide. Was. Thus, the firing temperature of the dielectric ceramic composition is set to 100
Some prior arts for reducing the temperature to around 0 ° C. are known. However, a technique for firing at a melting point of Ag of 962 ° C. or less, preferably 950 ° C. or less, and more preferably about 900 ° C. is still known. Not.

[0007]

The present invention has been made in view of the above circumstances, and has as its object to have a high relative dielectric constant, a large unloaded Q, and a high resonance frequency. 962 to give a dielectric ceramic with a small temperature coefficient
At a sintering temperature of less than or equal to
Sintering is possible at a sintering temperature of about ℃, and a large amount of Pb
An object of the present invention is to provide a dielectric ceramic composition for low-temperature firing that does not need to contain an oxide, and an advantageous method for producing the same.

In order to solve such a problem, the present inventors have made various studies and found that BaO-TiO _2-
Against RE ₂ O ₃ -Bi ₂ O ₃ based dielectric ceramic composition, by incorporating a small amount of a predetermined ZnO-B ₂ O ₃ -SiO ₂ based glass, while ensuring the excellent properties, They have found that the firing temperature can be advantageously reduced.

[0009]

That is, the present invention has been completed based on such findings, and the features thereof are as follows.
General formula: xBaO · yTiO ₂ · z [(1-a) RE ₂
O ₃ .aBi ₂ O ₃ ] (where, RE represents a rare earth metal), and x, y, z and a in the general formula are respectively the following formulas: 0.10 ≦ x ≦ 0.20,0.
60 ≦ y ≦ 0.75, 0.10 ≦ z ≦ 0.25, x + y
+ Z = 1, and a composition composed of barium oxide, titanium oxide, rare earth oxide, and bismuth oxide, satisfying 0 <a ≦ 0.3, as a main component, and 100 parts by weight of the main component composition With respect to the general formula: k (% by weight) Z
nO · m (% by weight) B ₂ O ₃ · n (% by weight) SiO ₂
(However, 30 ≦ k ≦ 85, 5 ≦ m ≦ 50, 2 ≦ n ≦ 4
0, k + m + n = 100)
-B ₂ O ₃ -SiO ₂ -based glass as a subcomponent
1 part by weight or more and (18-62.5a) parts by weight or less (when 0 <a ≦ 0.2) or 5.5 parts by weight or less (when 0.2 <a ≦ 0.3) In the proportion of
A dielectric ceramic composition for low-temperature firing characterized by being contained.

In the present invention, the general formula: xBa
O · yTiO ₂ · z _{[(1-a) RE 2 O} 3 · aBi 2
O ₃ ] (where, RE represents a rare earth metal), and x, y, z and a in the general formula are each represented by the following formula: 0.10 ≦ x ≦ 0.20,0 .60 ≦ y ≦
0.75, 0.10 ≦ z ≦ 0.25, x + y + z = 1,
And up to 2.5 parts by weight of aluminum oxide per 100 parts by weight of the composition comprising barium oxide, titanium oxide, rare earth oxide and bismuth oxide, which is configured to satisfy 0 <a ≦ 0.3. What is added,
The main component composition is represented by the following general formula: k (% by weight) ZnO · m (% by weight) B _{2 with} respect to 100 parts by weight of the main component composition
O ₃ · n (% by weight) SiO ₂ (however, 30 ≦ k ≦ 85,
0.1 wt parts or more of ZnO—B ₂ O ₃ —SiO ₂ based glass having a composition represented by 5 ≦ m ≦ 50, 2 ≦ n ≦ 40, k + m + n = 100 (18-6)
2.5a) by weight or less (provided that 0 <a ≦ 0.2)
Or a dielectric ceramic composition for low-temperature firing characterized in that it is contained in a proportion of not more than 5.5 parts by weight (provided that 0.2 <a ≦ 0.3). Therefore, the no-load Q can be further improved.

Further, in the present invention, the general formula: xB
aO · yTiO ₂ · z _{[(1-a) RE 2 O} 3 · aBi
₂ O ₃ ] (wherein RE represents a rare earth metal), and x, y, z and a in the general formula are represented by the following formulas: 0.10 ≦ x ≦ 0.20, 0.60 ≦ y ≦
0.75, 0.10 ≦ z ≦ 0.25, x + y + z = 1,
And up to 3 parts by weight of manganese oxide is added to 100 parts by weight of a composition comprising barium oxide, titanium oxide, rare earth oxide and bismuth oxide, which is configured to satisfy 0 <a ≦ 0.3. Is a main component composition, and 100 parts by weight of the main component composition is represented by a general formula: k (% by weight) ZnO · m (% by weight) B ₂ O ₃ .n
(% By weight) SiO ₂ (however, 30 ≦ k ≦ 85, 5 ≦ m ≦
50, 2 ≦ n ≦ 40, k + m + n = 100) ZnO—B ₂ O ₃ —SiO ₂ -based glass having a composition represented by the following formula:
4 parts by weight or less (provided that 0 <a ≦ 0.2) or
A low-temperature firing dielectric ceramic composition characterized in that it is contained at a ratio of 5 parts by weight or less (provided that 0.2 <a ≦ 0.3). Thus, simultaneous firing with a conductor can be advantageously achieved, and further, the unloaded Q can be further improved while maintaining a high relative dielectric constant, and the temperature coefficient of the resonance frequency can be reduced.

In the present invention, at the time of producing such a dielectric ceramic composition for low-temperature firing, at least a part of bismuth oxide as a constituent component of the raw material composition for providing the main component composition is used. the minus the while grinding by calcination, such excluded bismuth oxide, together with the auxiliary component serving ZnO-B ₂ O ₃ -SiO ₂ based glass,
The incorporation into the calcined and pulverized product is also a gist of the invention, and by manufacturing according to such a configuration, a remarkable decrease in the firing temperature can be promoted.

In producing such a low-temperature fired dielectric ceramic composition, a material obtained by removing at least a part of bismuth oxide as a constituent component from a raw material composition for providing the main component composition is heated to 1050 ° C. or more. After calcination at a temperature of the above, the obtained calcined product is finely pulverized so that the average particle size becomes 0.8 μm or less, and the removed bismuth oxide is converted into the above-mentioned auxiliary component ZnO—B ₂ O ₃ − If the dielectric porcelain composition is manufactured by mixing it with the calcined and pulverized material together with the SiO ₂ glass, the decrease in the firing temperature of the dielectric porcelain composition is remarkably promoted. An increase in the rate and an increase in the no-load Q can also be advantageously achieved.

Further, the present invention provides a dielectric resonator having a dielectric pattern and a conductor pattern formed in the dielectric ceramic by co-firing with the dielectric ceramic, or a dielectric filter comprising the resonator. In the above, the dielectric porcelain is obtained by sintering the dielectric porcelain composition as described above, in other words, the dielectric porcelain obtained by firing the dielectric porcelain composition according to any one of claims 1 to 3. On the other hand, a dielectric resonator or a dielectric filter comprising the resonator, characterized in that the conductor pattern is formed of Ag alone or an alloy material containing Ag as a main component. is there.

Further, the present invention provides a method for manufacturing a dielectric resonator having a dielectric ceramic and a conductor pattern provided in the dielectric ceramic or a dielectric filter comprising the resonator. 2. The method of claim 1, wherein
A molded body made of the dielectric ceramic composition according to any one of claims 3 to 3 or a calcined product thereof, wherein the conductor pattern is provided with a conductor layer formed of Ag alone or an alloy material containing Ag as a main component. The invention also provides a method for manufacturing a dielectric resonator or a dielectric filter comprising the resonator, wherein the dielectric resonator is provided and co-fired.

[0016]

In the dielectric ceramic composition, when the content of BaO, one of the main components, is less than 10 mol% (x <0.10), the relative dielectric constant of the obtained dielectric ceramic Is low, while 2
If it exceeds 0 mol% (x> 0.20), there arises a problem that the temperature coefficient of the resonance frequency becomes too large. When the content of TiO ₂ is less than 60 mol% (y <0.60), sintering becomes difficult and a dense sintered body cannot be obtained. On the other hand, when it exceeds 75 mol% (y> 0.7
5) There is a problem that the temperature coefficient of the resonance frequency becomes too large in the positive direction.

Further, regarding the total amount of RE ₂ O ₃ and Bi ₂ O ₃ , in other words, [(1-a) RE ₂ O ₃ .aBi
The value of the ₂ O _3], when the content of the sum is less than 10 mole% (z <0.10), the temperature coefficient of resonant frequency becomes too positive large, whereas, the 25 mole% If it exceeds (z> 0.25), there arises a problem that the sinterability is poor and the relative dielectric constant is reduced.

In the present invention, RE (rare earth metal) in RE ₂ O ₃ includes Nd, Sm, La, C
e, Pr, etc. Among them, Nd or Nd or Sm and / or La is preferably used in combination with Nd. N
When Sm and / or La are used in combination with d, the temperature coefficient of the resonance frequency can be controlled while maintaining a high relative permittivity and no-load Q. However, when such Sm and / or La are combined, the ratio of Sm or La to the entire RE is desirably 20 mol% or less, and if it exceeds that, the temperature coefficient of the resonance frequency becomes negative. Or, a problem of a large change occurs. In the case where Ce or Pr is used as RE, it is introduced after being converted into trivalent atoms.

Further, when RE ₂ O ₃ is replaced with Bi ₂ O ₃ , the relative dielectric constant is increased, and the temperature coefficient of the resonance frequency can be reduced. In particular, in order to obtain a sufficient substitution effect by Bi ₂ O ₃ , 5 mol% or more (a ≧
0.05) is desirable. However, BiO ₂
It reaches the substitution amount more than 15 to 20 mole percent of, and in the temperature coefficient begins to increase, also as the substitution amount of Bi ₂ O ₃ increases, since the unloaded Q decreases, Bi ₂ O
The substitution amount of ₃ is practically 30 mol% or less (a ≦ 0.3
0) is appropriate.

According to the present invention, a porcelain composition composed of barium oxide, titanium oxide, a rare earth oxide and bismuth oxide is used as a main component in the above ratio. On the other hand, as will be described later, a predetermined auxiliary component is mixed and contained. In addition, for such a main component porcelain composition, improvement of no-load Q and correction of temperature coefficient of resonance frequency are performed. For the purpose, aluminum oxide, iron oxide, manganese oxide, chromium oxide,
Addition of a metal oxide such as zinc oxide, tin oxide, or zirconium oxide may be performed at all. In particular, the addition of aluminum oxide to the main component porcelain composition is extremely effective in further improving the no-load Q. In addition, manganese oxide has a function of preventing the main component composition from being reduced, so that simultaneous sintering with a copper conductor or the like in nitrogen can be advantageously achieved. This has the effect of improving the load Q or reducing the temperature coefficient of the resonance frequency. In addition, this aluminum oxide or manganese oxide is 2.5 parts per 100 parts by weight of the composition composed of barium oxide, titanium oxide, rare earth oxide and bismuth oxide, respectively.
They will be added and contained in proportions of up to 3 parts by weight, preferably up to 2 parts by weight.

In addition, ZnO-B added as an auxiliary component to the main component porcelain composition according to the present invention.
_{The 2} O ₃ —SiO ₂ glass is composed of 30 to 85% by weight of zinc oxide (ZnO) and 5 to 50% by weight of boron oxide (B ₂
O ₃ ) and 2 to 40% by weight of silicon oxide (SiO ₂ ). That is, the contents of zinc oxide, boron oxide, and silicon oxide are k weight% and m weight%, respectively.
And n weight%, the following equation: 30 ≦ k ≦ 8
5,5 ≦ m ≦ 50,2 ≦ n ≦ 40, k + m + n = 100
It is necessary to satisfy. In particular, Z
By adding nO, B ₂ O ₃ , and SiO ₂ as glass, it is possible to effectively lower the sintering temperature, and among the components constituting such glass, S
The iO ₂ component is extremely important in producing glass, and not only facilitates vitrification, but also provides stable glass.

When the content (k) of ZnO is less than 30% by weight, there is a problem that vitrification becomes difficult. On the other hand, when the content exceeds 85% by weight, vitrification becomes difficult. In addition, there arises a problem that the firing temperature of the target dielectric ceramic composition becomes high. If the content (m) of B ₂ O ₃ is less than 5% by weight, vitrification becomes difficult, and the firing temperature of the dielectric ceramic composition becomes high. When it comes to
This causes a problem that the no-load Q becomes small. Furthermore, SiO ₂
When the content (n) exceeds 40% by weight, not only the vitrification becomes difficult, but also the problem that the firing temperature of the target dielectric ceramic composition becomes high is caused. Also,
By making this SiO ₂ one of the glass components, vitrification is facilitated, which can advantageously contribute to low-temperature firing of the dielectric ceramic composition, and further contributes to improvement of no-load Q. Can be done.

[0023] It should be noted that, according ZnO-B ₂ O ₃ -SiO ₂
The preferred composition range of the system glass, the content of ZnO (k) is 40 to 75 wt%, the content of B ₂ O ₃ (m) 10 to 40 wt%, the content of SiO ₂ (n) is 5 ~ 30
% By weight. In addition, the glass as such an auxiliary component may be allowed to contain impurities such as various metal oxides, but the content of such impurities is generally limited to a ratio of up to 10% by weight based on the glass. Should. Furthermore,
Used in the present invention ZnO-B ₂ O ₃ -SiO ₂
As the system glass, not only the whole is uniformly vitrified, but also if it is in a substantially glassy state, even if it is phase-separated, the raw material partially remains or is partially Even if it is crystallized,
It can be used as well.

The ZnO-B ₂ O having such a composition
_{The 3-} SiO ₂ -based glass is used as a sub-component in an amount of 0.1 parts by weight or more and (18-62.5a) parts by weight or less (where 0 <a ≦
0.2) or 5.5 parts by weight or less (however, 0.2
<A ≦ 0.3).
Thus, the firing temperature of the target dielectric ceramic composition is 1000
C. or lower, preferably around 900 ° C. On the other hand, when the content of the glass as such a sub-component is less than 0.1 part by weight, a sufficient effect of lowering the firing temperature due to the addition of such a sub-component cannot be obtained. When 0 <a ≦ 0.2, (1
8-62.5a) Exceeding parts by weight or 0.2 <a ≦
In the case of adding more than 5.5 parts by weight at 0.3, there is a problem that the unloaded Q of the obtained dielectric porcelain becomes too small to be practical.

The dielectric porcelain composition according to the present invention is different from the aforementioned main component porcelain composition in the Z
Although nO-B ₂ O ₃ -SiO ₂ based glass is manufactured by allowed formulated as a secondary component, serving according subcomponent Z
nO-B ₂ O ₃ prior to the formulation of -SiO ₂ based glass,
The above-mentioned main component porcelain composition is prepared by calcining and pulverizing the raw material composition giving the composition. Then, at the time of calcination, 900 ° C
When the above calcination temperature is employed, a decrease in the calcination temperature of the dielectric ceramic composition, an increase in the relative dielectric constant, and an increase in the no-load Q accompanying the increase in the calcination temperature are recognized. In particular, 1050 ° C
At the above calcination temperature, the effect is remarkable,
In the present invention, calcination is preferably performed at a temperature of 1050 ° C. or more. However, if the calcination temperature is 1350
If the temperature exceeds ℃, the calcined product will be hardened significantly after calcination, causing a problem in handling. Therefore, a calcination temperature of preferably 1200 to 1300 ° C is advantageously employed.

When the calcined material obtained by calcining in this way is pulverized, the lower the average particle size of the pulverized material, the more the reduction in the firing temperature of the dielectric ceramic composition is promoted, and It is possible to increase the permittivity and the unloaded Q. Therefore, in the present invention, 0.8
The calcined product is pulverized so as to have an average particle size of not more than μm. However, when the average particle diameter of the calcined and pulverized product is smaller than 0.1 μm, the moldability of the obtained dielectric porcelain composition is reduced, for example, since it becomes difficult to form a tape by a normal doctor blade method or the like, It is desirable to control the average particle size of the calcined and pulverized product to about 0.1 to 0.8 μm. In addition, the particle diameter of such a fine pulverized product is generally measured by using a laser diffraction scattering method.

Further, when producing the dielectric ceramic composition according to the present invention, at least a part of bismuth oxide constituting the main component composition is replaced with ZnO-B _{2 as a} subcomponent.
It can be added later together with the O ₃ —SiO ₂ glass. That is, the raw material composition for providing the main component composition as described above, except for removing at least a part of the bismuth oxide as a constituent component, is calcined and pulverized, while the bismuth oxide thus removed is replaced with a sub-component. Barrel ZnO-B ₂
It is incorporated into the calcined and pulverized product together with the O ₃ —SiO ₂ -based glass, whereby the firing temperature of the obtained dielectric ceramic composition can be effectively reduced. Then, as the post-addition ratio of the bismuth oxide increases, the lowering of the firing temperature is promoted. However, when the post-addition ratio of the bismuth oxide exceeds 50% by weight, the no-load Q
From the viewpoint that the decrease in the amount of the bismuth oxide is caused, it is desirable that the post-addition ratio of bismuth oxide is 50% by weight or less. That is, 50% of bismuth oxide constituting the main component composition is used.
In amounts up to% by weight, they are added later.

[0028]

EXAMPLES Hereinafter, some examples of the present invention will be described to clarify the present invention more specifically. However, the present invention does not impose any restrictions due to the description of such examples. Needless to say, it is not what we receive. In addition, various changes, modifications, improvements, and the like can be made to the present invention based on the knowledge of those skilled in the art without departing from the spirit of the present invention, in addition to the examples described below. Should be understood.

Example 1 Using high-purity barium carbonate, titanium oxide, neodymium oxide, samarium oxide, lanthanum oxide and bismuth oxide,
These components were weighed so as to give various x, y, z, RE, and a values shown in Tables 1 and 2 below, and the remaining raw materials except for a predetermined portion of bismuth oxide added later were used. Into a polyethylene pot were charged with alumina cobblestone, pure water was added, and the mixture was wet-mixed. And
After the obtained mixture was taken out of the pot and dried, it was placed in an alumina crucible and calcined at various temperatures of 900 to 1270 ° C. for 4 hours in an air atmosphere. Next, the calcined product was crushed, again put together with zirconia cobblestone into a polyethylene pot, and the average particle diameter measured using a laser diffraction scattering method was 0.4 to 1.0.
Pulverization was carried out until the particle size reached μm to obtain various calcined and pulverized products.

On the other hand, high-purity zinc oxide, boron oxide, and silicon oxide were used, and these were made of ZnO: 65% by weight, B ₂ O
₃ : 25% by weight and SiO ₂ : 10% by weight were weighed, put into a polyethylene pot together with alumina boulders, and dry mixed. Then, the obtained mixture is melted in a chamotte crucible,
Quenched in water and vitrified. The obtained glass was put into an alumina pot together with alumina boulders, and pulverized in ethanol until the average particle diameter became 4 μm to obtain a glass represented by composition: G.

Next, the various calcined and pulverized products thus obtained, bismuth oxide to be added later, and a predetermined amount of glass having the composition: G (the amounts shown in Tables 1 and 2) were added together with the alumina cobblestone. The mixture was put into a polyethylene pot, pure water was added, and the mixture was wet-mixed. At that time, P
1% by weight of VA was added. After drying the resulting mixture,
Aperture: Granulated through a 355 μm sieve. Note that the Bi ₂ O ₃ after the addition amount in Table 1 and Table 2, Bi ₂ O
₃ shows the ratio of the post-addition amount to the total use amount, and the glass addition amount shows the ratio of the total amount of the calcined and ground product and the post-addition amount of Bi ₂ O ₃ to 100 parts by weight.

The granulated powder thus obtained was molded at a surface pressure of 1 t / cm ² by using a press molding machine,
A disk-shaped test piece having a size of φ × 15 mm ^t was obtained. Then, the obtained test piece is heated at 900 ° C. in air.
By sintering at a temperature of 2 hours, various dielectric ceramic samples were produced. Furthermore, polishing the sample obtained by this firing to the size of the disc-shaped diameter of 16 mm × 8 mm ^t, respectively, to measure the dielectric properties. The relative permittivity (εr) and the no-load Q are measured by a parallel conductor plate type dielectric resonator method, and the temperature coefficient of resonance frequency (τf)
Was measured in the range of −25 ° C. to 75 ° C. The measurement frequency was 2 to 4 GHz. The obtained results are shown in Tables 1 and 2.

[0033]

[Table 1]

[0034]

[Table 2]

Example 2 High purity barium carbonate, titanium oxide, neodymium oxide, samarium oxide and bismuth oxide were prepared by adding x, y, z and a in the general formula indicating the composition of the main component composition to 0.14.
5, 0.675, 0.180, and 0.20, and RE = 0.90Nd + 0.10Sm, and the remaining raw materials except for 5% by weight of bismuth oxide were used. By calcining at a temperature of 1170 ° C. and pulverizing in the same manner as in Example 1, a calcined and pulverized product having an average particle diameter of 0.6 μm was obtained.

On the other hand, zinc oxide, boron oxide and silicon oxide were weighed so as to have the weight ratios shown in Table 3 below, vitrified in the same manner as in Example 1, and further pulverized to reduce the average particle diameter. Various glass powders of 4 μm were obtained.

[0037]

[Table 3]

Next, the obtained various glass powders are
Each of the calcined and pulverized materials was blended with bismuth oxide (5% by weight) of the post-addition, and the sample was press-molded in the same manner as in Example 1;
Fired in air for hours. The amounts of the various glass powders shown in Table 4 indicate the ratio of the total amount of the calcined and pulverized material and the post-added bismuth oxide to 100 parts by weight.

With respect to the various fired samples thus obtained, their dielectric properties were measured in the same manner as in Example 1. The results are shown in Table 4 below. In each case, the firing temperature was as low as 900 ° C. Regardless of the temperature, each of the obtained dielectric ceramics (sintered bodies) had a high relative dielectric constant, a large unloaded Q, and a small temperature coefficient of the resonance frequency.

[0040]

[Table 4]

Embodiment 3 In the embodiment 1, no. The calcined and pulverized product obtained as No. 12 was used, and the bismuth oxide post-addition (25% by weight)
And the composition in Example 2: ZnO—B _{2 of} G
O ₃ -SiO ₂ based glass powder, polyvinyl butyral,
The plasticizer and the deflocculant were put together with zirconia cobblestone into an alumina pot, and a mixed solution of toluene and isopropyl alcohol was further added and wet-mixed.

Then, the mixture was defoamed and formed into a green tape having a thickness of 250 μm by a doctor blade method. Then, a conductive pattern of a 900 MHz band three-stage bandpass filter was printed on the obtained green tape using a printing Ag paste. Next, twelve green tapes were heated at a temperature of 100 so as to sandwich the green tape on which the conductor pattern was printed.
The layers were laminated under the conditions of a temperature of 100 ° C. and a pressure of 100 kgf / cm ² . Then, after cutting the laminate, 900 ° C. in air.
By baking at a temperature of 2 hours, a strip line type filter was produced. Using the network analyzer to measure the filter characteristics of the stripline filter thus obtained, the center frequency:
930 MHz, insertion loss: 2.8 dB.

Example 4 High-purity barium carbonate, titanium oxide, neodymium oxide and bismuth oxide were converted to x, y, z and a in the above general formula.
Are weighed to be 0.155, 0.670, 0.175 and 0.05, respectively, and in the same manner as in Example 1,
By calcining at a temperature of 1270 ° C. and pulverizing, a calcined and pulverized product having an average particle diameter of 0.6 μm was obtained.

Next, 100 parts of the obtained calcined and pulverized
Composition prepared in Example 2 based on parts by weight: I
Were mixed in various proportions shown in Table 5 below, and a molded sample was press-molded in the same manner as in Example 1 and then fired.

The various fired samples thus obtained were measured for dielectric properties in the same manner as in Example 1, and the results are shown in Table 5 below.

[0046]

[Table 5]

Example 5 High-purity barium carbonate, titanium oxide, neodymium oxide and bismuth oxide were converted to x, y, z and a in the above general formula.
Are 0.155, 0.670, 0.175 and 0.05, respectively. Further, 100 parts by weight of the total amount of the weighed components are mixed at various ratios shown in Table 6 below. Aluminum oxide (Al ₂ O ₃ ) was externally added, calcined at a temperature of 1270 ° C. in the same manner as in Example 1, and pulverized to obtain an average particle diameter of 0.6 μm.
m of various calcined and pulverized products were obtained.

Then, 100 parts of the obtained calcined and pulverized
Composition prepared in Example 2 based on parts by weight: I
Example 1 was mixed with 5 parts by weight of the glass powder of Example 1.
The molded sample was press-molded in the same manner as described above, and then fired.

The dielectric properties of the various fired samples thus obtained were measured in the same manner as in Example 1, and the results are shown in Table 6 below.

[0050]

[Table 6]

Example 6 High-purity barium carbonate, titanium oxide, neodymium oxide, samarium oxide, lanthanum oxide and bismuth oxide were prepared in such a manner that x, y, z and a in the above-mentioned general formulas were as shown in Table 7 below. Manganese oxide (MnO) in various proportions shown in Table 7 below was added to 100 parts by weight of the total amount of the weighed components in the same manner as in Example 1. Calcined at a temperature of 1270 ° C,
By crushing, a calcined crushed product having an average particle size of 0.6 μm was obtained.

Next, 100 parts of the obtained calcined and pulverized
Composition prepared in Example 2 based on parts by weight: I
Alternatively, the glass powder of G was blended at various ratios shown in Table 7 below, and a molded sample was press-molded in the same manner as in Example 1 and then fired.

The dielectric properties of the various fired samples thus obtained were measured in the same manner as in Example 1, and the results are shown in Table 7 below.

[0054]

[Table 7]

[0055]

As is apparent from the above description, the dielectric porcelain composition according to the present invention comprises barium oxide (BaO),
Titanium oxide (TiO ₂ ), rare earth oxide (RE ₂ O
₃ ) Bismuth oxide (Bi ₂ O ₃ ) as a main component, each of which is contained in a specific amount, and ZnO—B ₂ O having a specific composition as a subcomponent.
_By containing a predetermined amount of 3-SiO ₂ glass, sintering can be performed at a firing temperature of 962 ° C. (the melting point of Ag) or lower, preferably at a firing temperature of around 900 ° C., A dielectric filter such as a stripline filter having an inner conductor made of Ag alone or an alloy material containing Ag as a main component having low conduction resistance can be advantageously manufactured, and the obtained dielectric porcelain is , High relative dielectric constant, large unloaded Q, and small temperature coefficient of resonance frequency.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-278417 (JP, A) JP-A-3-290358 (JP, A) JP-A-60-124306 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) C04B 35/46 H01B 3/02 H01B 3/12

Claims (7)

(57) [Claims] 1. A general formula: xBaO.yTiO ₂ .z
[(1-a) RE ₂ O ₃ · aBi ₂ O ₃ ] (provided that RE
Represents a rare earth metal), and x, y, z and a in the general formula each represent the following formula: 0.10 ≦ x
≦ 0.20, 0.60 ≦ y ≦ 0.75, 0.10 ≦ z ≦
A composition comprising barium oxide, titanium oxide, rare earth oxide and bismuth oxide, which is constituted so as to satisfy 0.25, x + y + z = 1, and 0 <a ≦ 0.3, as a main component, and the main component composition To 100 parts by weight of the following formula: k (% by weight) ZnO · m (% by weight) B ₂ O ₃ .n
(% By weight) SiO ₂ (however, 30 ≦ k ≦ 85, 5 ≦ m ≦
50, 2 ≦ n ≦ 40, k + m + n = 100) ZnO—B ₂ O ₃ —SiO ₂ -based glass having a composition represented by the following formula:
4 parts by weight or less (provided that 0 <a ≦ 0.2) or
A dielectric ceramic composition for low-temperature firing, wherein the dielectric ceramic composition is contained in a proportion of 5 parts by weight or less (provided that 0.2 <a ≦ 0.3). 2. General formula: xBaO.yTiO ₂ .z
[(1-a) RE ₂ O ₃ · aBi ₂ O ₃ ] (provided that RE
Represents a rare earth metal), and x, y, z and a in the general formula each represent the following formula: 0.10 ≦ x
≦ 0.20, 0.60 ≦ y ≦ 0.75, 0.10 ≦ z ≦
100 of a composition comprising barium oxide, titanium oxide, rare earth oxide and bismuth oxide, which is configured to satisfy 0.25, x + y + z = 1, and 0 <a ≦ 0.3.
A composition obtained by adding up to 2.5 parts by weight of aluminum oxide with respect to parts by weight is defined as a main component composition, and 100 parts by weight of the main component composition has a general formula: k (% by weight) ZnO · m (% by weight) B ₂ O ₃ · n (% by weight) Si
O ₂ (however, 30 ≦ k ≦ 85, 5 ≦ m ≦ 50, 2 ≦ n ≦
40, k + m + n = 100)
The O-B ₂ O ₃ -SiO ₂ based glass, as a sub-component,
0.1 parts by weight or more and (18-62.5a) parts by weight or less (when 0 <a ≦ 0.2) or 5.5 parts by weight or less (however, 0.2 <a ≦ 0.3 (Low), the dielectric ceramic composition for low-temperature firing. 3. General formula: xBaO.yTiO ₂ .z
[(1-a) RE ₂ O ₃ · aBi ₂ O ₃ ] (provided that RE
Represents a rare earth metal), and x, y, z and a in the general formula each represent the following formula: 0.10 ≦ x
≦ 0.20, 0.60 ≦ y ≦ 0.75, 0.10 ≦ z ≦
100 of a composition comprising barium oxide, titanium oxide, rare earth oxide and bismuth oxide, which is configured to satisfy 0.25, x + y + z = 1, and 0 <a ≦ 0.3.
A composition obtained by adding up to 3 parts by weight of manganese oxide with respect to parts by weight is defined as a main component composition.
· M (% by weight) B ₂ O ₃ · n (% by weight) SiO ₂ (30 ≦ k ≦ 85, 5 ≦ m ≦ 50, 2 ≦ n ≦ 40, k
+ M + n = 100) ZnO—B _{2 having} a composition represented by
The O ₃ -SiO ₂ based glass, as a secondary component, 0.1 part by weight or more, (18-62.5A) parts by weight (where 0 <
a ≦ 0.2) or 5.5 parts by weight or less (however,
0.2 <a ≦ 0.3). A dielectric ceramic composition for low-temperature firing. 4. The method of producing a dielectric ceramic composition for low-temperature firing according to claim 1, wherein a bismuth oxide serving as a constituent component of the dielectric ceramic composition for providing a main component composition is prepared from the raw material composition. the minus at least a part, while ground by calcination, such excluded bismuth oxide, together with the auxiliary component serving ZnO-B ₂ O ₃ -SiO ₂ based glass and allowed formulated provisional sintered pulverized product A method for producing a dielectric porcelain composition for low-temperature firing, characterized in that: 5. The method of producing a dielectric ceramic composition for low-temperature firing according to claim 1, wherein a bismuth oxide, which is a constituent component of the dielectric ceramic composition for providing a main component composition, is prepared. Excluding at least a part, 10
After calcining at a temperature of 50 ° C. or higher, the obtained calcined material is finely pulverized so that the average particle size is 0.8 μm or less.
The removed bismuth oxide is converted to ZnO as the sub-component.
-B with ₂ O ₃ -SiO ₂ -based glass, preparation of low temperature fired dielectric ceramic composition characterized in that allowed to blend in the temporary baking pulverized product. 6. A dielectric resonator having a dielectric porcelain and a conductor pattern formed in said dielectric porcelain by co-firing with said dielectric porcelain, or a dielectric filter comprising said resonator. 2. The body porcelain according to claim 1,
A dielectric ceramic composition obtained by firing the dielectric ceramic composition according to any one of claims 3 to 3, while the conductive pattern is formed of Ag alone or an alloy material containing Ag as a main component. A dielectric resonator or a dielectric filter comprising the resonator. 7. When manufacturing a dielectric resonator having a dielectric ceramic and a conductor pattern provided in the dielectric ceramic or a dielectric filter including the resonator, providing the dielectric ceramic. A molded body made of the dielectric ceramic composition according to any one of claims 1 to 3, or a calcined product thereof, which is formed of Ag alone or an alloy material containing Ag as a main component to give the conductor pattern. A method for manufacturing a dielectric resonator or a dielectric filter comprising said resonator, wherein a conductor layer is provided and co-fired.