JP2526702B2 - Dielectric porcelain composition - Google Patents
Dielectric porcelain compositionInfo
- Publication number
- JP2526702B2 JP2526702B2 JP2097315A JP9731590A JP2526702B2 JP 2526702 B2 JP2526702 B2 JP 2526702B2 JP 2097315 A JP2097315 A JP 2097315A JP 9731590 A JP9731590 A JP 9731590A JP 2526702 B2 JP2526702 B2 JP 2526702B2
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- dielectric
- low
- temperature
- dielectric constant
- weight
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Description
【発明の詳細な説明】 産業上の利用分野 本発明は、主にマイクロ波帯域と言われる領域におい
て使用される共振器等を構成する高周波用誘電体磁器組
成物に関する。TECHNICAL FIELD The present invention relates to a high frequency dielectric ceramic composition that constitutes a resonator or the like used mainly in a region called a microwave band.
従来の技術 近年、自動車電話、携帯電話、コードレス電話などの
無線通信機に使用される空中線共用器(デュプレクサ
ー)や電圧制御発振器等に使用される共振器、あるいは
CATV用チューナに使用されるフィルタ等に高周波用誘電
体磁器が多く用いられている。この様な共振器等におい
て高誘電率材料を使用することにより、高周波の波長を
真空中の の長さに短縮し、かかる周波数における1波長、1/2波
長、あるいは1/4波長のマイクロ波を高周波誘電体磁器
の中に閉じ込め、所定の作用効果が得られるように、小
形に構成したものが一般的に知られている。このような
高周波用誘電体磁器に要求される特性としては、 (1)誘電体中では電磁波の波長が に短縮され、同じ共振周波数ならば誘電率が大きい程小
形化できるため、可能な限り誘電率が大であること、 (2)高周波帯域での誘電損失が小さいこと、 (3)共振周波数の温度変化に対する変化率が少ないこ
と、すなわち誘電率の温度依存性が小さくかつ安定であ
ること、 の3特性が挙げられる。2. Description of the Related Art In recent years, antennas used in wireless communication devices such as car phones, mobile phones and cordless phones, duplexers, resonators used in voltage controlled oscillators, etc., or
High frequency dielectric porcelain is often used for filters used in CATV tuners. By using a high dielectric constant material in such a resonator, etc. The length was shortened to 1, and the microwave of 1 wavelength, 1/2 wavelength, or 1/4 wavelength at such frequency was confined in the high frequency dielectric porcelain, and it was constructed in a small size so as to obtain a predetermined effect. Things are generally known. The characteristics required for such a high frequency dielectric porcelain include: (1) the wavelength of the electromagnetic wave in the dielectric The dielectric constant can be made smaller as the dielectric constant increases, so that the dielectric constant is as large as possible. (2) Dielectric loss in the high frequency band is small. (3) Resonance frequency temperature There are three characteristics: the change rate with respect to the change is small, that is, the temperature dependence of the dielectric constant is small and stable.
また、マイクロ波帯域でも自動車電話、パーソナル無
線、コードレステレホン等に用いられる比較的低周波帯
域とされる1GHz程度の領域において適用する場合、波長
がかなり長くなるため、共振器等の小形化を図るために
は誘電体磁器組成物としては誘電率がかなり高いものを
必要とする。Also, in the microwave band, when applied in the region of about 1 GHz, which is a relatively low frequency band used for car phones, personal radios, cordless telephones, etc., the wavelength becomes considerably long, so the resonator etc. should be miniaturized. Therefore, the dielectric ceramic composition needs to have a considerably high dielectric constant.
従来、この種の誘電体磁器組成物としては、例えば、
BaO−Nd2O3−TiO2−Bi2O3系組成物、BaO−Nd2O3−TiO2
−PbO系組成物などが知られている。Conventionally, as this type of dielectric ceramic composition, for example,
BaO-Nd 2 O 3 -TiO 2 -Bi 2 O 3 based compositions, BaO-Nd 2 O 3 -TiO 2
-PbO-based compositions and the like are known.
発明が解決しようとする課題 しかしながら、これらの材料においても誘電率はεr
=70〜90程度であり、それ以上の高い誘電率のものを得
ようとすると、急激にQ値が劣化するか、あるいは温度
特性が劣化し、誘電率を上げ共振器等の小形化を図るに
は限度があった。However, even in these materials, the dielectric constant is εr.
= 70 to 90, and if a dielectric constant higher than that is to be obtained, the Q value will suddenly deteriorate or the temperature characteristics will deteriorate, and the dielectric constant will be increased to reduce the size of the resonator. There was a limit.
また、誘電体グリーンシートに内部電極ペーストを印
刷してそれらを積層し、その後前記内部電極ペーストと
前記誘電体グリーンシートを同時焼結させ、この焼結体
に外部電極を形成した、いわゆる積層形の誘電体共振
器、フィルタとすることにより、内部導体形状を色々な
形状に設計し、前記焼結体の大きさを共振波長に比べて
大幅に小さくすることも考えられている。In addition, the internal electrode paste is printed on the dielectric green sheet to stack them, and then the internal electrode paste and the dielectric green sheet are co-sintered, and external electrodes are formed on this sintered body, a so-called laminated type. It is also considered that the dielectric resonator and the filter of (1) are used to design the shape of the inner conductor into various shapes, and the size of the sintered body is made significantly smaller than the resonance wavelength.
しかしマイクロ波帯域で使用される電極には低抵抗で
あることが要求されるため、この帯域における共振器等
では一般に電極としてAu、Ag、Cu、Al等の金属が使用さ
れており、同時焼結させるにはそれらの金属の融点より
も低い温度で焼結する組成物が必要になる。However, since electrodes used in the microwave band are required to have low resistance, metals such as Au, Ag, Cu, and Al are generally used as electrodes in resonators in this band, and co-firing The composition requires a composition that sinters at a temperature below the melting point of those metals.
しかしながら、従来の高周波用誘電体磁器は1300〜15
00℃で焼結されており、マイクロ波帯域で適しているA
u、Ag、Cu等の金属材料を内部電極材料として採用する
ことができないといった課題があった。However, the conventional high frequency dielectric porcelain is 1300-15
Sintered at 00 ℃, suitable for microwave band A
There is a problem that metallic materials such as u, Ag and Cu cannot be adopted as the internal electrode material.
本発明は上記した課題に鑑み発明されたものであっ
て、高周波用共振器等のより一層の小形化を可能とす
る、誘電率が高く、誘電損失が低く、誘電率の温度依存
性が小さくかつ安定で、従って製造される誘電体共振器
の共振周波数の温度依存性が小さく、しかもAu、Ag−Pd
等を内部電極材料として使用できる低温で焼結可能な誘
電体磁器組成物を提供することを目的としている。The present invention has been made in view of the above problems, and enables further miniaturization of high-frequency resonators, etc., high permittivity, low dielectric loss, and low temperature dependence of the permittivity. It is stable and therefore has a small temperature dependence of the resonance frequency of the manufactured dielectric resonator, and Au, Ag-Pd
It is an object of the present invention to provide a dielectric ceramic composition that can be used as an internal electrode material and that can be sintered at a low temperature.
課題を解決するための手段 本発明者は上記課題に対して、研究を重ねた結果、Ba
O、Nd2O3、Sm2O3、TiO2、PbO、Bi2O3からなる系にGe
O2、B2O3、ZnOを添加することによって、高誘電率で誘
電率の温度依存性の小さい、即ち共振周波数の温度依存
性が小さく、かつ、高Q値の特性を有し、しかも、Au、
Ag−Pdを内部導体として使用できる1000〜1050℃の低温
で焼結できる誘電体磁器組成物が得られることを知見
し、本発明を完成するに至った。Means for Solving the Problems As a result of repeated research on the above problems, the present inventor
In the system consisting of O, Nd 2 O 3 , Sm 2 O 3 , TiO 2 , PbO and Bi 2 O 3 , Ge
By adding O 2 , B 2 O 3 and ZnO, the dielectric constant is high and the temperature dependence of the dielectric constant is small, that is, the temperature dependence of the resonance frequency is small and the Q value is high. , Au,
The inventors have found that a dielectric ceramic composition capable of sintering Ag-Pd as an internal conductor at a low temperature of 1000 to 1050 ° C. can be obtained, and completed the present invention.
即ち、本発明に係る誘電体磁器組成物は、組成式が xBaO・y{(Nd2O3)1−α(Sm2O3)α}・zTiO2・uPb
O・vBi2O3 ただし 0.090<x<0.160 0.130<y<0.160 0.650<z<0.700 0.045<u<0.080 0.005<v<0.045 x+y+z+u+v=1 0≦α<0.25 で示される主成分に対し、副成分として GeO2が1.0〜4.0重量% ZnOが0.75〜3.5重量%及び B2O3が0.75〜3.5重量% の割合で添加されていることを特徴としている。That is, the dielectric ceramic composition according to the present invention has a composition formula of xBaO · y {(Nd 2 O 3 ) 1-α (Sm 2 O 3 ) α } · zTiO 2 · uPb
O ・ vBi 2 O 3 However, 0.090 <x <0.160 0.130 <y <0.160 0.650 <z <0.700 0.045 <u <0.080 0.005 <v <0.045 x + y + z + u + v = 1 0 ≦ α <0.25 with respect to the main component As a characteristic feature, GeO 2 is added in an amount of 1.0 to 4.0% by weight, ZnO is added in an amount of 0.75 to 3.5% by weight, and B 2 O 3 is added in an amount of 0.75 to 3.5% by weight.
作用 本発明の誘電体磁器組成物の主成分は、REO(希土類
酸化物)−BaO−TiO2系にPbOとBi2O3を加えた組成で、
希土類酸化物としてNd2O3とSm2O3を用いている。そし
て、これに1000℃〜1050℃の低温焼結を可能とするた
め、副成分としてGeO2、ZnO、B2O3を添加している。Action The main component of the dielectric ceramic composition of the present invention is a composition obtained by adding PbO and Bi 2 O 3 to the REO (rare earth oxide) -BaO-TiO 2 system,
Nd 2 O 3 and Sm 2 O 3 are used as rare earth oxides. Then, GeO 2 , ZnO, and B 2 O 3 are added as subcomponents to enable low temperature sintering at 1000 ° C to 1050 ° C.
本発明においては、希土類酸化物としてNd2O3とSm2O3
の二種類を用いている。これは次の様な理由による。こ
の系において、誘電率、Q値が良好で、焼結温度の低い
組成点においては、共振周波数の温度係数τfを調整す
るために、希土類酸化物量(本発明においては、Nd2O3
とSm2O3のトータル量)を変化させると、他の特性が劣
化する。他方、Nd2O3、Sm2O3は両方とも共振周波数の温
度係数τfをマイナス側へ移行させる性質を有している
が、Sm2O3の方がその効果が大であり、両者の割合を考
慮することにより誘電率、Q値をあまり変化させずにτ
fを調整できるからである。従って、Nd2O3とSm2O3の割
合を変化させることにより、適正な範囲にτfが調整さ
れる。In the present invention, Nd 2 O 3 and Sm 2 O 3 are used as rare earth oxides.
Two types are used. This is due to the following reasons. In this system, at the composition point where the dielectric constant and Q value are good and the sintering temperature is low, in order to adjust the temperature coefficient τf of the resonance frequency, the amount of rare earth oxide (in the present invention, Nd 2 O 3
And the total amount of Sm 2 O 3 ) are changed, other characteristics deteriorate. On the other hand, both Nd 2 O 3 and S m2 O 3 have the property of shifting the temperature coefficient τf of the resonance frequency to the negative side, but Sm 2 O 3 has the greater effect and both By considering the ratio, τ
This is because f can be adjusted. Therefore, τf is adjusted to an appropriate range by changing the ratio of Nd 2 O 3 and Sm 2 O 3 .
各成分が上記範囲を逸脱した場合、1000℃〜1050℃の
低温での焼結が不可能になるか、あるいは可能な場合で
も誘電率εrが低かったり、あるいは共振周波数の温度
係数が、±20ppm/℃の範囲を出たり、あるいは、Q値
が、1500以下と低くなる。If each component deviates from the above range, it becomes impossible to sinter at a low temperature of 1000 ° C to 1050 ° C, or even if possible, the dielectric constant εr is low, or the temperature coefficient of the resonance frequency is ± 20ppm. It goes out of the range of / ° C or the Q value becomes as low as 1500 or less.
実施例及び比較例 (I)誘電体磁器の調整 高純度の炭酸バリウム(BaCO3)、酸化ネオジウム(N
d2O3)、酸化サマリウム(Sm2O3)、酸化チタン(Ti
O2)、酸化鉛(PbO)、酸化ビスマス(Bi2O3)酸化ゲル
マニウム(GeO2)、酸化亜鉛(ZnO)、無水ホウ酸(B2O
3)をそれぞれ第1表に示した比率で秤量した。Examples and Comparative Examples (I) Preparation of Dielectric Porcelain High-purity barium carbonate (BaCO 3 ), neodymium oxide (N
d 2 O 3 ), samarium oxide (Sm 2 O 3 ), titanium oxide (Ti
O 2 ), lead oxide (PbO), bismuth oxide (Bi 2 O 3 ), germanium oxide (GeO 2 ), zinc oxide (ZnO), boric anhydride (B 2 O)
3 ) were weighed in the ratios shown in Table 1, respectively.
上記出発原料をボールミルにて一昼夜湿式混合した後
乾燥させた。The above starting materials were wet mixed for one day in a ball mill and then dried.
上記混合物を900℃程度の温度で約2時間仮焼した。The above mixture was calcined at a temperature of about 900 ° C. for about 2 hours.
仮焼した混合物をボールミルにて一昼夜湿式粉砕した
後乾燥させた。The calcined mixture was wet-ground for one day in a ball mill and then dried.
上記乾燥粉末に約1重量%のバインダを添加して整粒
した。About 1% by weight of a binder was added to the above dry powder to adjust the size.
約1000kg/cm2の圧力で成形し、975〜1350℃で約2時
間空気中にて焼成した。It was molded at a pressure of about 1000 kg / cm 2 and baked at 975 to 1350 ° C. for about 2 hours in the air.
(II)特性の測定 得られた誘電体磁器を誘電体円柱共振器法により、共
振周波数3.0〜4.0GHzにおいて誘電率、Q値及び共振周
波数の温度係数について測定した。(II) Measurement of characteristics The obtained dielectric porcelain was measured for dielectric constant, Q value and temperature coefficient of resonance frequency at a resonance frequency of 3.0 to 4.0 GHz by a dielectric cylinder resonator method.
結果を第1表に示す。 The results are shown in Table 1.
以下実施例のものと比較例のものとを比べ、本発明に
係る組成範囲外での比較例における問題点を述べる。 The problems in the comparative example outside the composition range according to the present invention will be described below by comparing the example and the comparative example.
x>0.160の場合:No.9の様に焼結温度が高くなる。When x> 0.160: The sintering temperature becomes high like No. 9.
x<0.090の場合:No.8の様にQ値が低くなる。When x <0.090: Q value becomes low as No.8.
y>0.160の場合:No.10の様に焼結温度が高くなる。When y> 0.160: The sintering temperature becomes high as in No. 10.
y<0.130の場合:No.9の様にQ値が低くなる。When y <0.130: Q value becomes low as No.9.
z>0.700の場合:No.11の様にQ値が低くなる。When z> 0.700: The Q value decreases as in No. 11.
z<0.650の場合:No.12の様にQ値が低くなる。When z <0.650: Q value becomes low like No.12.
u>0.080の場合:No.12の様にQ値が低くなる。When u> 0.080: Q value becomes low as No.12.
u<0.045の場合:No.13の様にQ値が低くなる。When u <0.045: The Q value becomes low as in No. 13.
v>0.045の場合:No.13の様にQ値が低くなる。When v> 0.045: The Q value becomes low like No.13.
v<0.005の場合:No.14の様に焼結温度が高くなる。When v <0.005: The sintering temperature becomes high like No.14.
α>0.25の場合:No.5の様にτfが負側に大となる。When α> 0.25: τf becomes large on the negative side as in No.5.
GeO2>4.0重量%の場合:No.21の様に焼結温度が高くな
る。When GeO 2 > 4.0% by weight: The sintering temperature becomes high like No. 21.
GeO2<1.0重量%の場合:No.23の様にQ値が低くなる。When GeO 2 <1.0% by weight: Q value becomes low as No.23.
ZnO>3.5重量%の場合:No.22の様にQ値が低くなる。When ZnO> 3.5% by weight: Q value becomes low as No.22.
ZnO<0.75重量%の場合:No.23の様にQ値が低くなる。When ZnO <0.75% by weight: Q value is low as in No. 23.
B2O3>3.5重量%の場合:No.23の様にQ値が低くなる。When B 2 O 3 > 3.5% by weight: Q value becomes low as No.23.
B2O3<0.75重量%の場合:No.22、No.24の様に焼結温度
が高くなる。When B 2 O 3 <0.75% by weight: The sintering temperature becomes high like No.22 and No.24.
このように比較例のものでは上記のような問題点が残
る。As described above, the above-mentioned problems remain in the comparative example.
一方、本発明に係る組成の範囲内のものであるNo.1,
2,3,4,6,7,15,16,17,18,19,20については、誘電率がε
r=69.3〜75.6と高く、Q値もf・Q=1691〜2836と高
く、また共振周波数の温度係数τfもτf=−16.5〜+
6.3ppm/℃と安定で、しかも975〜1050℃の低温で焼結で
き、本発明の目的が達成されている。On the other hand, No. 1, which is within the composition range according to the present invention.
For 2,3,4,6,7,15,16,17,18,19,20, the permittivity is ε
r = 69.3 to 75.6, high Q value f · Q = 1691 to 2836, and resonance frequency temperature coefficient τf τf = -16.5 to +
It is stable at 6.3 ppm / ° C. and can be sintered at a low temperature of 975 to 1050 ° C., thus achieving the object of the present invention.
発明の効果 以上の説明により明らかなように、本発明に係る誘電
体磁器組成物にあっては、BaO、Nd2O3Sm2O3、TiO2、Pb
O、Bi2O3を主成分とし、副成分としてGeO2、ZnO、B2O3
が所定量添加されており、誘電率及びQ値が高く、しか
も共振周波数の温度依存性が小さく、さらにはAu、Ag−
Pdを内部電極として使用できる、低温で焼結可能な誘電
体磁器組成物を得ることができる。Effects of the Invention As is apparent from the above description, in the dielectric ceramic composition according to the present invention, BaO, Nd 2 O 3 Sm 2 O 3 , TiO 2 , Pb
O, Bi 2 O 3 as main components, and GeO 2 , ZnO, B 2 O 3 as secondary components
Is added in a predetermined amount, the dielectric constant and Q value are high, the temperature dependence of the resonance frequency is low, and Au, Ag-
It is possible to obtain a dielectric ceramic composition which can be used as an internal electrode and which can be sintered at a low temperature.
従って、高周波用共振器、フィルタ等の大幅な小形化
が可能になり、その有用性は極めて大きい。Therefore, the size of the high-frequency resonator, the filter, etc. can be greatly reduced, and the usefulness thereof is extremely large.
Claims (1)
O・vBi2O3 ただし 0.090<x<0.160 0.130<y<0.160 0.650<z<0.700 0.045<u<0.080 0.005<v<0.045 x+y+z+u+v=1 0≦α<0.25 で示される主成分に対し、副成分として GeO2が1.0〜4.0重量% ZnOが0.75〜3.5重量%及び B2O3が0.75〜3.5重量% の割合で添加されていることを特徴とする誘電体磁器組
成物。1. A composition formula of xBaO · y {(Nd 2 O 3 ) 1-α (Sm 2 O 3 ) α } · zTiO 2 · uPb
O ・ vBi 2 O 3 However, 0.090 <x <0.160 0.130 <y <0.160 0.650 <z <0.700 0.045 <u <0.080 0.005 <v <0.045 x + y + z + u + v = 1 0 ≦ α <0.25 with respect to the main component GeO 2 is added in an amount of 1.0 to 4.0% by weight, ZnO is added in an amount of 0.75 to 3.5% by weight, and B 2 O 3 is added in an amount of 0.75 to 3.5% by weight.
Priority Applications (1)
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JP2097315A JP2526702B2 (en) | 1990-04-11 | 1990-04-11 | Dielectric porcelain composition |
Applications Claiming Priority (1)
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JP2097315A JP2526702B2 (en) | 1990-04-11 | 1990-04-11 | Dielectric porcelain composition |
Publications (2)
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JPH03295855A JPH03295855A (en) | 1991-12-26 |
JP2526702B2 true JP2526702B2 (en) | 1996-08-21 |
Family
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Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5264403A (en) * | 1991-09-27 | 1993-11-23 | Ngk Insulators, Ltd. | Dielectric ceramic composition containing ZnO-B2 O3 -SiO2 glass |
US5479140A (en) * | 1991-09-27 | 1995-12-26 | Ngk Insulators, Ltd. | Dielectric ceramic composition containing ZnO-B2 O3 -SiO2 glass, method of preparing the same, and resonator and filter using the dielectric ceramic composition |
JP2613722B2 (en) * | 1991-09-27 | 1997-05-28 | 日本碍子株式会社 | Method for producing dielectric ceramic composition for low-temperature firing |
JPH05334914A (en) * | 1992-05-29 | 1993-12-17 | Sumitomo Metal Ind Ltd | Dielectric porcelain composition |
JP2858073B2 (en) * | 1992-12-28 | 1999-02-17 | ティーディーケイ株式会社 | Multilayer ceramic parts |
EP1036777B1 (en) | 1999-03-16 | 2003-06-04 | TDK Corporation | Composition of dielectric ceramics and producing method therefor |
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JPH03295855A (en) | 1991-12-26 |
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