JPS5849969B2 - Sankabutsuyudenzairiyouno Seizouhouhou - Google Patents

Sankabutsuyudenzairiyouno Seizouhouhou

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Publication number
JPS5849969B2
JPS5849969B2 JP49119967A JP11996774A JPS5849969B2 JP S5849969 B2 JPS5849969 B2 JP S5849969B2 JP 49119967 A JP49119967 A JP 49119967A JP 11996774 A JP11996774 A JP 11996774A JP S5849969 B2 JPS5849969 B2 JP S5849969B2
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Japan
Prior art keywords
temperature
composition
sintering
hot press
pressure
Prior art date
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Expired
Application number
JP49119967A
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Japanese (ja)
Other versions
JPS5145799A (en
Inventor
秀男 高見沢
正則 鈴木
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NEC Corp
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Nippon Electric Co Ltd
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Priority to JP49119967A priority Critical patent/JPS5849969B2/en
Publication of JPS5145799A publication Critical patent/JPS5145799A/ja
Publication of JPS5849969B2 publication Critical patent/JPS5849969B2/en
Expired legal-status Critical Current

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Description

【発明の詳細な説明】 本発明はS rO* CaO+ BaOr Nb2O5
の成分で構成され誘電率温度係数の小さい酸化物誘電材
料の製造方法に関するものである。
DETAILED DESCRIPTION OF THE INVENTION The present invention provides S rO* CaO+ BaOr Nb2O5
The present invention relates to a method for manufacturing an oxide dielectric material having a small dielectric constant temperature coefficient.

本発明の目的は誘電率εが太き(、誘電体損失(tan
δ)が小さく、かつ誘電率温度係数(以下εT−にと記
す)は請求範囲の所望の組成に選択することで正または
負の温度変化を示すマイクロ波誘電材料およびコンデン
サ材料に適した組成物を提供することである。
The purpose of the present invention is to increase the dielectric constant ε (and dielectric loss (tan)).
δ) is small and the dielectric constant temperature coefficient (hereinafter referred to as εT-) is suitable for microwave dielectric materials and capacitor materials that exhibit positive or negative temperature changes by selecting the desired composition within the claimed range. The goal is to provide the following.

マイクロ波領域において誘電材料は従来からマイクロ波
回路のインピーダンスの整合、誘電体共振器等に応用さ
れている。
In the microwave region, dielectric materials have been conventionally applied to impedance matching of microwave circuits, dielectric resonators, etc.

特に近来通信網の増加に伴い使用周波数領域も低域ある
いは準ミリ波、ミリ波領域と広がりマイクロ波IC化の
要請と共にその技術が進歩し、発振器の周波数の安定化
、遅延時間の制御フィルタ、およびマイクロ波回路用I
C基板等に高誘電率、低損失の誘電材料を使った小型化
の検討が積極的に進められている。
In particular, with the recent increase in the number of communication networks, the frequency range used has expanded to the low range, sub-millimeter wave, and millimeter wave ranges, and the technology has advanced along with the demand for microwave ICs, stabilizing the oscillator frequency, delay time control filters, and I for microwave circuits
The use of dielectric materials with high permittivity and low loss for C substrates and other materials is actively being considered for miniaturization.

従来の一般的な誘電材料としてはBa0−TIO2系の
ものが知られている。
Ba0-TIO2-based materials are known as conventional general dielectric materials.

それらの材料のεT−には負で大きい値を示し、正のε
The εT− of those materials shows a large negative value, and the positive εT−
.

、には得られない。またアルiす焼結体やMgTiO3
+ CaTiO3系等は正のεT、には得られるがεが
低い欠点がある。
, cannot be obtained. Also, aluminum sintered bodies and MgTiO3
+ CaTiO3 type etc. can obtain positive εT, but have the disadvantage of low ε.

本発明はこれらの欠点を除いたものであり、新たに5r
O−CaO−BaO−Nb205で構成される( 1−
a )(2(Sr1−xCax)O−yNb205〕a
(2(Ca1−wBaw)0−zNb205 〕で示す
組成物をホットプレスの方法で合成することにより優れ
たマイクロ波優電材料、コンデンサ材料を提供するもの
であることを見い出したものである。
The present invention eliminates these drawbacks and newly provides 5r
Composed of O-CaO-BaO-Nb205 (1-
a)(2(Sr1-xCax)O-yNb205]a
It has been discovered that by synthesizing the composition represented by (2(Ca1-wBaw)0-zNb205) by a hot pressing method, an excellent microwave euelectric material and capacitor material can be provided.

5i−Ca−NbとCa−Ba−Nb系の組成物は単独
、かつ普通焼成でも良好な特性を有する。
The 5i-Ca-Nb and Ca-Ba-Nb compositions have good properties when used alone or when fired normally.

例えば2(Sr、−xCax)O−yNb205および
2(Ca1xBax)0−yNb205の化学式でx、
yの値をそれぞれx=0.4 、 y=1.0とした組
成物の特性はCa−Ba−Nbのそれぞれεは43.8
および59.7 。
For example, in the chemical formulas 2(Sr, -xCax)O-yNb205 and 2(Ca1xBax)0-yNb205, x,
The properties of the composition with y values of x = 0.4 and y = 1.0 are as follows: ε of Ca-Ba-Nb is 43.8.
and 59.7.

tanδはそれぞれ3X10− およびlXl0”ある
tan δ are 3×10− and 1×10″, respectively.

またε。、には正であり、後者は負である。これを5r
−Ca−NbとCa −B a−(’J、、b系の組成
物のε。
Also ε. , is positive, and the latter is negative. 5r of this
-Ca-Nb and Ca-B a-('J, ε of the b-based compositions.

、KがO近傍になるように比率で組合せた組成物をつく
り焼成した場合に加算効果によりε。
, ε due to the additive effect when a composition is made and fired in such a ratio that K is close to O.

、にはO附近の値を示すであろうと考えられる。, is considered to have a value around O.

しかし普通焼結では加算効果はない。However, ordinary sintering has no additive effect.

これは5r−Ca−Nb とCa −B a−N bの
相が混在せず、固相反応を行ない別の相になるためであ
ることを見い出した。
It has been found that this is because the 5r-Ca-Nb and Ca-Ba-Nb phases do not coexist and undergo a solid phase reaction to become separate phases.

そこで各種の粉末製作法、焼結法を用いて試作した材料
について物性的評価した結果5r−Ca−Nb および
Ca−Ba−Nb各々の成分が各々独立に存在した混和
セラミックを得るためにホットプレス方法を用いること
が最も優れておりこの場合には加算効果が認められ所望
のものを得ることができることを見い出した。
Therefore, as a result of physical evaluation of materials prototyped using various powder manufacturing methods and sintering methods, hot pressing was performed to obtain a mixed ceramic in which 5r-Ca-Nb and Ca-Ba-Nb components existed independently. It has been found that it is best to use this method, and in this case, an additive effect is observed and the desired result can be obtained.

ホットプレス焼結の場合、普通焼結に比し低い温度、短
い時間で物理的に焼成されるため混相セラ□ツクをつ(
り得ることが可能である。
In the case of hot press sintering, it is physically fired at a lower temperature and in a shorter time than normal sintering, so it is difficult to use a multiphase ceramic.
It is possible to obtain

ココで本発明は(1−α)l:2(5rl−xCax)
0・yNb205 :) clc 2 (Ca1−wB
aw)O−zNb205 )であられされる化学式にお
いてそれぞれα、X。
Here, the present invention is (1-α)l:2(5rl-xCax)
0・yNb205 :) clc 2 (Ca1-wB
aw)O-zNb205), α and X, respectively.

y、w、zの値がO,<a< 1.0 、 O<x<、
1.0 。
The values of y, w, and z are O,<a<1.0, O<x<,
1.0.

0、5 <y<2.0 、 O<w<2.0を満足する
組成範囲内で温度1ooo〜1400℃圧力は10〜1
000 Kg/crAの各条件でホットプレスし製造す
ることを特徴とするものである。
Within the composition range that satisfies 0, 5 < y < 2.0, O < w < 2.0, the temperature is 1 ooo to 1400°C and the pressure is 10 to 1
It is characterized by being manufactured by hot pressing under various conditions of 000 Kg/crA.

本発明にかかる材料はS r O* Ca O* B
a O5Nb20.の原料を各組成に応じて秤量しボー
ルミルにて混合後1000℃−4hrで仮焼し圧縮成形
後1000〜140 ooc、 10〜1000KVc
rtiで1時間空気中でホットプレスを行なって得られ
たものである。
The material according to the present invention is S r O* Ca O* B
a O5Nb20. The raw materials are weighed according to each composition, mixed in a ball mill, calcined at 1000℃ for 4 hours, and then compression molded at 1000 to 140 ooc, 10 to 1000 KVc.
It was obtained by hot pressing in air for 1 hour at RTI.

その後εの常温測定および温度係数測定をXバンドの周
波数で誘電体共振器法で測定した。
Thereafter, ε was measured at room temperature and the temperature coefficient was measured using a dielectric resonator method at an X-band frequency.

以下実施例にもとづいて詳細に説明する。実施例 1 (1−a)〔2(Sr1−xCax)O−yNb205
〕a〔2(Ca1−wBaw)O−ZNb205の化
学式でa:o、2 、 x=0.4 + y””1.0
* w=0.4 + z −1,0なる組成式をもつ
粉末についてホットプレス条件を温度11000〜14
00℃圧力O〜11000IL/c4と変えたときの各
特性の一部を第1表に示す。
A detailed explanation will be given below based on examples. Example 1 (1-a) [2(Sr1-xCax)O-yNb205
]a[2(Ca1-wBaw)O-ZNb205 chemical formula: a:o, 2, x=0.4 + y""1.0
*The hot press conditions for the powder with the composition formula w = 0.4 + z -1,0 were set at a temperature of 11,000 to 14
Table 1 shows some of the characteristics when changing the pressure from 00° C. to 11,000 IL/c4.

この表の中でホットプレスを用いない通常の方法で焼結
した材料の特性が便宜的に圧力0として付記されている
In this table, the properties of materials sintered by a normal method that does not use hot pressing are added as 0 pressure for convenience.

第1表に示すごとく、上記組成において普通焼結した場
合1400℃以上の温度範囲でないと充分な焼結体を得
ることはできない。
As shown in Table 1, when the above composition is normally sintered, a sufficient sintered body cannot be obtained unless the temperature range is 1400° C. or higher.

また1400℃で焼結したものはε=55と大きいが、
tanδ。
Also, the one sintered at 1400℃ has a large ε=55,
tanδ.

εT−にも大きくなり好ましくない。It also increases εT-, which is not preferable.

ホットプレス温度が1200℃のときは圧力が300
Kg/ca以上1250℃のときは100 Kg/ca
、以上、1300℃以上のときは50に7/crAで顕
著な効果がある。
When the hot press temperature is 1200℃, the pressure is 300℃
Kg/ca or more 100 Kg/ca when temperature is 1250℃
, above, when the temperature is 1300°C or higher, there is a remarkable effect of 50 to 7/crA.

本実施例と同様な種々の実験から適切な条件を用いるこ
とが圧力10〜1000 KglcrAの場合、普通焼
結に比べ50℃〜200℃低い温度でεの大きなかつt
anδ、εT−K の小さい良好な焼結体を得た。
From various experiments similar to those in this example, it is found that when the pressure is 10 to 1000 KglcrA, ε is large and t is 50 to 200 degrees lower than normal sintering.
A good sintered body with small an δ and εT−K was obtained.

また同様な実験から温度が1000℃以下では実用的な
限界圧力までホットプレス圧力を上げても充分な焼結体
は得られなかった。
Further, similar experiments have shown that when the temperature is below 1000°C, a sufficient sintered body could not be obtained even if the hot press pressure was increased to the practical limit pressure.

また、1400℃以上ではtanδI’T、K が大き
くなり、′かつホットプレス型の寿命も短くなり不経済
である。
Moreover, at 1400° C. or higher, tan δI'T,K increases, and the life of the hot press mold becomes short, making it uneconomical.

加圧力は10Kg/crA以下ではこの種の材料で実用
的な焼結温度限界と考えられる1 500℃以上の温度
でも充分なホットプレス効果は得られず、また1 00
0 Kg/ctA以上になると温度によってはホットプ
レス型の寿命は著しく短縮し高温ホットプレス同様不経
済で好ましくない。
If the pressing force is less than 10 kg/crA, this is considered to be the practical sintering temperature limit for this type of material. Even at temperatures of 1,500°C or more, a sufficient hot press effect cannot be obtained, and 1,000
If the temperature exceeds 0 Kg/ctA, the life of the hot press mold will be significantly shortened depending on the temperature, which is uneconomical and undesirable like a high temperature hot press.

実施例 2 (1−α)〔2(Sr1−XCaX)O−yNb205
〕αCCaw−18aw)0−zNb205〕の化学式
で組成比x−0,4+ y=1.0 、 w=o、4
+ z=1.Q、αの値O〜1.0とホットプレス条件
温度12000C〜1350℃、圧力0〜200Kq/
crAと変えた場合の各々材料特性の一部を第2表に示
す。
Example 2 (1-α) [2(Sr1-XCaX)O-yNb205
[αCCaw-18aw)0-zNb205] and the composition ratio x-0,4+ y=1.0, w=o,4
+z=1. Q, α value O ~ 1.0 and hot press conditions temperature 12000C ~ 1350C, pressure 0 ~ 200Kq/
Table 2 shows some of the material properties when crA is changed.

この表中でホットプレスを用いない通常の方法で焼結し
た材料の特性が便宜的に圧力0として併記しである。
In this table, the properties of materials sintered by a normal method that does not use hot pressing are also shown as 0 pressure for convenience.

第2表に、αの値を0.2〜0.6、温度12000C
−1350℃、加圧力200 Kg/crtt、の各条
件でホットプレスした場合の結果を表示しであるがこの
表から明らかなように普通焼結に比べαの値が変っても
、εは大差ないがtanδ、εT−K は小さく各組成
範囲でホットプレスト焼結の効果が認められる。
Table 2 shows the value of α from 0.2 to 0.6 and the temperature of 12000C.
The results are shown for hot pressing under the following conditions: -1350°C and a pressure of 200 Kg/crtt.As is clear from this table, even if the value of α changes compared to normal sintering, there is a large difference in ε. However, tan δ and εT−K are small, and the effect of hot presintering is recognized in each composition range.

なお同様な実験を0ζα<:0.2゜0.6<α<1.
00組組成囲でも行ない良好な結果が得られた。
A similar experiment was conducted with 0ζα<:0.2°0.6<α<1.
Good results were obtained even when the composition was within the range of 00 sets.

従ってホットプレス焼結を行なう場合、Oくα<1.0
の組成範囲でtanδ、εT、にの小さい焼結体を得る
ことができる。
Therefore, when performing hot press sintering, O α < 1.0
A sintered body with small tan δ and εT can be obtained within the composition range.

実施例 3 最終的な材料が巨視的に見て(1−α)(2(S’r。Example 3 Macroscopically, the final material is (1-α)(2(S’r).

CaX)O−yNb205〕α〔2(CaヶwBaw)
0・ZNb205〕の化学式においてx = 0.4
+ y=1.0 +w””0.4 、 z=1.0 、
(X=0.2なる組成物の場合についてホットプレス
前の粉末の混合方法を変えたときの実施例を示す。
CaX)O-yNb205]α[2(CagawBaw)
In the chemical formula of [0・ZNb205], x = 0.4
+y=1.0 +w””0.4, z=1.0,
(An example will be shown in which the method of mixing the powder before hot pressing was changed for the case of a composition where X=0.2.

いま簡単のために上記化学式第1項を係数(1−α)も
含めてA、第2項*を係数αも含めてBと表わす。
For the sake of simplicity, the first term of the above chemical formula is expressed as A, including the coefficient (1-α), and the second term *, including the coefficient α, is expressed as B.

(a)上述の組成となるようにSrO,Ca0sBaO
sNb205を(通常の方法)、(b)A、B各々を秤
量、別々にポール□ル混合、仮焼した後にA、Bを一緒
にしてらいかい機で混合、(c)A、B各々を別々に秤
量、混合、仮焼、加圧成形、焼結、粉砕等をした後にA
、Bを一緒にしてらいかい機で混合した。
(a) SrO, Ca0sBaO so as to have the above composition.
sNb205 (normal method), (b) Weigh each of A and B, mix them separately in a pole, and after calcining, mix A and B together in a sieve machine. (c) Each of A and B. After separately weighing, mixing, calcination, pressure forming, sintering, crushing, etc.
, B were combined and mixed in a rice paddle machine.

これら3種を温度12500〜1350℃、加圧力20
0〜400 Kg/crj、の条件でホットプレスによ
る焼結をし、その結果の一部を第3表に示す。
These three types were heated at a temperature of 12,500 to 1,350°C and a pressure of 20
Sintering was performed by hot press under the conditions of 0 to 400 Kg/crj, and some of the results are shown in Table 3.

本表中に通常に焼結したものを圧力Oとして表わしてい
る。
In this table, normally sintered products are expressed as pressure O.

第3表に示すごとく、混合方法をそれぞれ(aXb)(
c)と変えた場合でも普通焼結に比しホットプレス焼結
したものはいずれもtanδ、εr−&ま小さく各特性
とも良好でホットプレス焼結の著しい効果が認められる
As shown in Table 3, the mixing methods are (aXb) (
Even when the method is changed to (c), the tan δ, εr− & M of the hot press sintered products are smaller than that of the normal sintering, and each property is good, and the remarkable effect of the hot press sintering is recognized.

上記の他(1−α)(2(Sr1−Xcax)0−yN
b20.〕α〔2(Ca、−WBaW)0・ZN′b2
05〕の化学式でα””0.2 X + y+ w*
Zの値をそれぞれ0:<x<1.0 、0.5<y<2
.0 、 O<w<1.0 。
In addition to the above (1-α) (2(Sr1-Xcax)0-yN
b20. ]α[2(Ca, -WBaW)0・ZN'b2
05], α””0.2 X + y+ w*
The value of Z is 0:<x<1.0, 0.5<y<2, respectively.
.. 0, O<w<1.0.

0、5 <、 z <、2.0と変えた組成について実
験した場合でもホットプレス焼結は普通焼結に比しta
nδ。
Even when experimenting with different compositions such as 0, 5 <, z <, 2.0, hot press sintering has ta lower than normal sintering.
nδ.

εT、にの各特性は小さく良好な結果が得られた。Good results were obtained with each characteristic of εT being small.

このように実施例1〜3および他のいずれの組成範囲で
もホットプレス条件を各組成に応じ温度1000℃〜1
400℃、加圧力10−Cq/cttiの範囲内で選択
し焼結を行なうことでtanδ、εの温度変化のより小
さい誘電体を得るのに著しい効果が認められ有用な焼結
手段であることが明らかである。
In this way, in Examples 1 to 3 and any other composition range, the hot press conditions were adjusted to a temperature of 1,000°C to 1,000°C depending on each composition.
By performing sintering at a temperature of 400°C and a pressure of 10-Cq/ctti, a significant effect is observed in obtaining a dielectric material with smaller temperature changes in tan δ and ε, and it is a useful sintering method. is clear.

これらの方法で得られた材料はマイクロ波準ミリ波等の
領域においてεが大きくεT−Kが小さいマイクロ波誘
電材料として極めて有用な材料であることが明白である
It is clear that the materials obtained by these methods are extremely useful as microwave dielectric materials with large ε and small εT-K in the microwave, quasi-millimeter wave, and other regions.

なお本材料は低周波領域でもtanδが小さくεの温度
係数が小さい磁器コンンサとして優れた材料である。
Note that this material has a small tan δ and a small temperature coefficient of ε even in the low frequency range, making it an excellent material for use as a ceramic capacitor.

本発明の方法による材料は詳細に説明したように単一の
化学式で表わされるものではないが、本説明中では便宜
的に一つの化学式で組成を示しており、これによって本
発明の内容を左右するものではない。
Although the material produced by the method of the present invention is not represented by a single chemical formula as explained in detail, in this explanation, the composition is shown by a single chemical formula for convenience, and this will affect the content of the present invention. It's not something you do.

Claims (1)

【特許請求の範囲】 1 (1−α)[2(Srl−xCax)O−yNb
20.lα[2(Ca1−wBaw)0−zNb205
〕で表わされる化学式においてα、X、y1w、zの
値がそれぞれOくαζ1.0.0≦x<1.0 、0.
5 <y<2.0 。 O<w<1.0 、0.5≦z <−2,Oの組成範囲
からなる誘電体粉末を温度10000〜1400℃、加
圧力10〜1000 Kg/c4の条件範囲でホットプ
レスすることを特徴とする酸化物誘電材料の製造方法。
[Claims] 1 (1-α)[2(Srl-xCax)O-yNb
20. lα[2(Ca1-wBaw)0-zNb205
] In the chemical formula represented by α,
5<y<2.0. A dielectric powder having a composition range of O<w<1.0, 0.5≦z<-2, O is hot-pressed at a temperature of 10,000 to 1,400°C and a pressing force of 10 to 1,000 Kg/c4. A method for producing a featured oxide dielectric material.
JP49119967A 1974-10-17 1974-10-17 Sankabutsuyudenzairiyouno Seizouhouhou Expired JPS5849969B2 (en)

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JP49119967A JPS5849969B2 (en) 1974-10-17 1974-10-17 Sankabutsuyudenzairiyouno Seizouhouhou

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JP49119967A JPS5849969B2 (en) 1974-10-17 1974-10-17 Sankabutsuyudenzairiyouno Seizouhouhou

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JPS5145799A JPS5145799A (en) 1976-04-19
JPS5849969B2 true JPS5849969B2 (en) 1983-11-08

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54124300A (en) * 1978-03-20 1979-09-27 Nec Corp Dielectric material of oxide
JPS6135582A (en) * 1984-07-27 1986-02-20 Kyocera Corp Dielectric ceramic composite
JPH02196427A (en) * 1989-01-25 1990-08-03 Nec Corp Vapor growth method of metal oxide film
JP6249004B2 (en) * 2015-10-06 2017-12-20 Tdk株式会社 Dielectric composition and electronic component

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