JPH03278402A - Voltage non-linear ceramic composite and manufacture thereof - Google Patents

Voltage non-linear ceramic composite and manufacture thereof

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Publication number
JPH03278402A
JPH03278402A JP2076770A JP7677090A JPH03278402A JP H03278402 A JPH03278402 A JP H03278402A JP 2076770 A JP2076770 A JP 2076770A JP 7677090 A JP7677090 A JP 7677090A JP H03278402 A JPH03278402 A JP H03278402A
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JP
Japan
Prior art keywords
voltage
heated
nonlinear
zinc oxide
composition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2076770A
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Japanese (ja)
Other versions
JPH0648642B2 (en
Inventor
Noriyuki Kozu
典之 神津
Masaru Masuyama
増山 勝
Fumio Ishida
文男 石田
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Taiyo Yuden Co Ltd
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Taiyo Yuden Co Ltd
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Priority to JP2076770A priority Critical patent/JPH0648642B2/en
Publication of JPH03278402A publication Critical patent/JPH03278402A/en
Publication of JPH0648642B2 publication Critical patent/JPH0648642B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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  • Thermistors And Varistors (AREA)

Abstract

PURPOSE:To lower varistor voltage by firing a composite containing a metal oxide mainly composed of zinc oxide. CONSTITUTION:A composite mainly composed of zinc oxide and having an oxide of one kind or more of metals selected from Bi, Sb, Mn, Co, Ni, Cr, Mg, Al, Si as an auxiliary component is heated in a reducing atmosphere to 1100 to 1300 deg.C to be made semiconductive, and heated in an oxidizing atmosphere to 600 750 deg.C to oxidize the surface. In this way, varistor voltage can be lowered.

Description

【発明の詳細な説明】 [産業上の利用分野] 本発明は電圧非直線磁器組成物(非直線的な電圧−電流
特性を有し、電圧非直線抵抗体(バリスタ)の素体を形
成する磁器組成物)、特に酸化亜鉛を主成分とする電圧
非直線磁器組成物に関するものである。
[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a voltage nonlinear ceramic composition (having nonlinear voltage-current characteristics and forming an element body of a voltage nonlinear resistor (varistor). porcelain compositions), particularly voltage nonlinear porcelain compositions containing zinc oxide as a main component.

[従来の技術] 酸化亜鉛を主成分とする電圧非直線磁器組成物としては
、ZnO粉末に、例えばBi、Sb等の各種金属酸化物
粉末を添加して混合し、これらを例えばディスク形状に
成形した後、酸化性雰囲気中において1200℃程度の
温度で焼結したものが知られている。
[Prior Art] A voltage non-linear ceramic composition containing zinc oxide as a main component is prepared by adding and mixing various metal oxide powders such as Bi and Sb to ZnO powder, and forming the mixture into, for example, a disk shape. After that, it is known that the material is sintered at a temperature of about 1200° C. in an oxidizing atmosphere.

この例の電圧非直線磁器組成物では、焼結によって、電
圧非直線磁器組成物中にZnOからなる半導体粒子と、
この半導体粒子の粒界に形成されたBi2O3等の金属
酸化物の粒界相と、Z、nx Sbz 04等からなる
スピネル相とが形成される。
In the voltage nonlinear ceramic composition of this example, semiconductor particles made of ZnO are added to the voltage nonlinear ceramic composition by sintering.
A grain boundary phase of metal oxide such as Bi2O3 formed at the grain boundaries of the semiconductor particles and a spinel phase consisting of Z, nx Sbz 04, etc. are formed.

電圧非直線磁器組成物の非直線的な電圧−電流特性は、
このZnOからなる半導体粒子と81203等の金属酸
化物の粒界相との界面によって生ずるものである。
The nonlinear voltage-current characteristics of the voltage nonlinear porcelain composition are
This is caused by the interface between the semiconductor particles made of ZnO and the grain boundary phase of metal oxide such as 81203.

ところで、電圧非直線磁器組成物の非直線的な電圧−電
流特性は、バリスタ電圧Vと非直線係数aで評価される
By the way, the nonlinear voltage-current characteristics of the voltage nonlinear ceramic composition are evaluated by the varistor voltage V and the nonlinear coefficient a.

ここで、バリスタ電圧■は、電気抵抗が急激に減少する
ようになる電圧であり、非直線係数αは電圧非直線磁器
組成物中を流れる電流Iの電圧Vに対する変化を次式で
近似したときに得られる数値である。
Here, the varistor voltage ■ is the voltage at which the electrical resistance suddenly decreases, and the nonlinear coefficient α is when the change in the current I flowing through the voltage nonlinear ceramic composition with respect to the voltage V is approximated by the following equation. This is the numerical value obtained.

I=KVa (但し、■は電圧非直線磁器組成物中を流れる電流、■
は印加電圧、Kは定数) そして、酸化亜鉛を主成分とする電圧非直線磁器組成物
は、非直線係数αが50程度と大きいので、異常高電圧
(サージ)に対する応答性の点で特に優れている。
I=KVa (where ■ is the current flowing through the voltage nonlinear ceramic composition, ■
(applied voltage, K is constant) Voltage nonlinear ceramic compositions containing zinc oxide as a main component have a large nonlinear coefficient α of about 50, so they are particularly excellent in response to abnormally high voltages (surges). ing.

また、この酸化亜鉛を主成分とする電圧非直線磁器組成
物は、原料のZnOが安いので、安く製造することがで
きるものである。
Moreover, this voltage nonlinear ceramic composition containing zinc oxide as a main component can be manufactured at low cost because the raw material ZnO is cheap.

[発明が解決しようとする課題] しかし、この酸化亜鉛を主成分とする従来の電圧非直線
磁器組成物は、バリスタ電圧Vが200V程度と高いの
で、各種小型モータのような低電圧を使用する電気機器
から発生するノイズ除去用としては使用できなかった。
[Problem to be solved by the invention] However, since the conventional voltage non-linear porcelain composition containing zinc oxide as a main component has a high varistor voltage V of about 200 V, it is difficult to use a low voltage such as in various small motors. It could not be used to remove noise generated from electrical equipment.

本発明は、コストの安いZnO系の材料を使用して、バ
リスタ電圧の低い電圧非直線磁器組成物を得ることを目
的とするものである。
The present invention aims to obtain a voltage nonlinear ceramic composition with a low varistor voltage by using an inexpensive ZnO-based material.

[課題を解決するための手段] 本発明に係る電圧非直線磁器組成物は、酸化亜鉛を主成
分とし、副成分として少なくとも1種以上の金属酸化物
を含有する組成物を焼成してなる焼結体であって、この
焼結体は、還元されて半導体の状態にある半導体部と、
この半導体部の上に所定の厚さで層状に被覆形成された
酸化層とからなる。
[Means for Solving the Problems] The voltage nonlinear porcelain composition according to the present invention is produced by firing a composition containing zinc oxide as a main component and at least one metal oxide as a subcomponent. A solid body, the sintered body includes a semiconductor part that has been reduced and is in a semiconductor state,
An oxide layer is formed to cover the semiconductor portion in a layered manner with a predetermined thickness.

ここで、副成分としては、Bi、Sb、Mn。Here, the subcomponents include Bi, Sb, and Mn.

Co、Ni、Cr、Mg、AlおよびSiから選択され
た1種または2種以上の金属の酸化物を挙げることがで
きる。
Examples include oxides of one or more metals selected from Co, Ni, Cr, Mg, Al, and Si.

この電圧非直線磁器組成物は、酸化亜鉛を主成分とし、
副成分として少なくとも1種以上の金属酸化物を含有す
る上記組成物を所定形状に成型した後、還元性雰囲気中
において加熱して半導体化させ、次に酸化性雰囲気中に
おいて加熱して表面を酸化させることにより製造するこ
とができる。
This voltage nonlinear porcelain composition has zinc oxide as a main component,
After the composition containing at least one metal oxide as a subcomponent is molded into a predetermined shape, it is heated in a reducing atmosphere to convert it into a semiconductor, and then heated in an oxidizing atmosphere to oxidize the surface. It can be manufactured by

ここで、還元性雰囲気中における加熱温度としては、1
100〜1300℃の範囲が好ましい。
Here, the heating temperature in the reducing atmosphere is 1
The temperature range is preferably from 100 to 1300°C.

加熱温度が1100℃未満では焼結が不充分になり、1
300℃を越えるとBigotのような低融点の副成分
が抜け、特性に悪影響を及ぼすが、1100〜1300
℃の範囲ではこのようなことがないからである。
If the heating temperature is less than 1100°C, sintering will be insufficient, and 1
If the temperature exceeds 300℃, low melting point subcomponents such as Bigot will come out, which will have a negative effect on the properties, but
This is because this does not occur in the temperature range of ℃.

また、酸化性雰囲気中における加熱温度としては600
〜750℃の範囲が好ましい。加熱温度が600℃未満
ではバリスタ電圧■が低くなり過ぎたり、非直線係数α
が小さくなり過ぎ、また750℃を越えるとバリスタ電
圧■が高くなり過ぎるが、600〜750℃の範囲では
バリスタ電圧Vや非直線係数αが適当な値になるからで
ある。
In addition, the heating temperature in an oxidizing atmosphere is 600°C.
A range of 750°C is preferred. If the heating temperature is less than 600℃, the varistor voltage ■ may become too low or the nonlinear coefficient α
This is because if the temperature becomes too small and the temperature exceeds 750°C, the varistor voltage (2) becomes too high, but in the range of 600 to 750°C, the varistor voltage V and the nonlinear coefficient α become appropriate values.

また、この電圧非直線磁器組成物は、酸化亜鉛を主成分
とし、副成分として少なくとも1種以上の金属酸化物を
含有する上記組成物を所定形状に成型した後、酸化性雰
囲気中において加熱して酸化させ、次に還元性雰囲気中
において加熱して還元させ、次に酸化性雰囲気中におい
て加熱して表面を再酸化させることによっても製造する
ことができる。
In addition, this voltage nonlinear porcelain composition is produced by molding the composition containing zinc oxide as a main component and at least one metal oxide as a subcomponent into a predetermined shape, and then heating it in an oxidizing atmosphere. It can also be produced by heating in a reducing atmosphere to reduce the surface, and then heating in an oxidizing atmosphere to reoxidize the surface.

ここで、先の酸化性雰囲気中における加熱温度としては
、1100〜1300℃の範囲が好ましい。加熱温度が
1100℃未満では焼結が不充分になり、1300℃を
越えるとB i z O3のような低融点の副成分が抜
け、特性に悪影響を及ぼすが、1.100〜1300℃
の範囲ではこのようなことがないからである。
Here, the heating temperature in the oxidizing atmosphere is preferably in the range of 1100 to 1300°C. If the heating temperature is less than 1,100°C, sintering will be insufficient, and if it exceeds 1,300°C, low melting point subcomponents such as B iz O3 will come out, which will have a negative effect on the properties.
This is because this does not occur within the range of .

また、還元性雰囲気中における加熱温度としては700
〜1100℃の範囲が好ましい。加熱温度が700℃未
満では還元が不充分で、完全にバリスタ特性を除くこと
ができず、1100℃を越えると粒子成長が進み初期の
特性が悪くなるが、700〜1100℃の範囲ではこの
ようなことがないからである。
In addition, the heating temperature in a reducing atmosphere is 700°C.
A range of 1100°C to 1100°C is preferred. If the heating temperature is less than 700℃, the reduction will be insufficient and the varistor characteristics cannot be completely removed, and if the heating temperature exceeds 1100℃, particle growth will progress and the initial characteristics will deteriorate, but in the range of 700 to 1100℃ This is because there is no such thing.

更に、後の酸化性雰囲気中における加熱温度としては6
00〜750℃の範囲が好ましい。加熱温度が600℃
未満ではバリスタ電圧■が低くなり過ぎたり、非直線係
数αが小さくなり過ぎ、また750℃を越えるとバリス
タ電圧■が高くなり過ぎるが、600〜750℃の範囲
ではバリスタ電圧■や非直線係数αが適当な値になるか
らである。
Furthermore, the heating temperature in the oxidizing atmosphere was 6.
The temperature range is preferably from 00 to 750°C. Heating temperature is 600℃
Below 750°C, the varistor voltage ■ becomes too low and the nonlinear coefficient α becomes too small, and when it exceeds 750°C, the varistor voltage ■ becomes too high, but in the range of 600 to 750°C, the varistor voltage This is because it becomes an appropriate value.

[実施例] 実験1 ZnO粉末にBi、Sb、Mn、Co、Ni。[Example] Experiment 1 Bi, Sb, Mn, Co, and Ni in ZnO powder.

Cr、Mg、AlまたはSiから選択された元素の酸化
物を、第1表の試料No3,15.27に示す割合で添
加し、これらを充分に混合した後、720℃で2時間仮
焼した。
An oxide of an element selected from Cr, Mg, Al, or Si was added in the proportion shown in Sample No. 3, 15.27 in Table 1, and after thoroughly mixing these, the mixture was calcined at 720°C for 2 hours. .

次に、この仮焼して得られたものを充分に粉砕し、この
粉砕したものを金型で成型して、外径12.25mm、
内径7.75mmのリング状の成形体を複数個製造した
Next, the calcined material was thoroughly ground, and the ground material was molded into a mold with an outer diameter of 12.25 mm.
A plurality of ring-shaped molded bodies having an inner diameter of 7.75 mm were manufactured.

次に、このリング状の成形体をH,2,0%十N298
%の還元性雰囲気中において、1150℃で2時間焼成
し、その後、空気中において650℃で酸化焼成した。
Next, this ring-shaped molded body was made of H, 2.0% and N298.
% reducing atmosphere at 1150°C for 2 hours, and then oxidation firing at 650°C in air.

次に、この酸化焼成したものに銀電極を各々焼き付けて
バリスタを形成し、25℃におけるバリスタ電圧V、。
Next, silver electrodes are baked on each of the oxidized and fired products to form a varistor, and the varistor voltage is V at 25°C.

、と、非直線係数aを求めた。, and the nonlinear coefficient a was calculated.

結果は第1表に示す通りとなった。The results were as shown in Table 1.

実験2 次に、添加成分を第1表の試料No37,38゜39に
示すようにしたこと、および成形体を酸化性雰囲気中に
おいて加熱温度1150℃で1回だけ加熱して酸化焼成
したこと以外は実!1i1と同様にして従来例としての
バリスタを形成し、25℃におけるバリスタ電圧V l
o+aAと、非直線係数aを求めた。
Experiment 2 Next, except that the additive components were as shown in Sample Nos. 37 and 38°39 in Table 1, and the molded body was heated only once at a heating temperature of 1150°C in an oxidizing atmosphere and oxidized and fired. Fruit! A varistor as a conventional example was formed in the same manner as 1i1, and the varistor voltage V l at 25°C was
o+aA and the nonlinear coefficient a were determined.

結果は第1表に示す通りとなった。The results were as shown in Table 1.

※ × ※ 実験1によれば、バリスタ電圧■1゜、Aは5〜35V
となった。これは実験2の結果、すなわち従来例と比較
して大巾に低下していることがわかる。
* × * According to experiment 1, varistor voltage ■1°, A is 5 to 35V
It became. It can be seen that this is a large decrease compared to the results of Experiment 2, that is, the conventional example.

実験1のバリスタ電圧■1゜□が、実験2のバリスタ電
圧V to□よりも大幅に低くなったのは、実験2で得
られた電圧非直線磁器組成物がBL槽構造なっているの
に対して、実験1で得られた電圧非直線磁器組成物が表
面再酸化型の構造になっているためと考えられる。
The reason why the varistor voltage ■1゜□ in Experiment 1 was significantly lower than the varistor voltage V to □ in Experiment 2 is because the voltage nonlinear porcelain composition obtained in Experiment 2 had a BL tank structure. On the other hand, this is considered to be because the voltage nonlinear ceramic composition obtained in Experiment 1 has a surface reoxidation type structure.

実験3 次に、第2表の試料No1〜6.13〜18゜25〜3
0に示す組成の成形体を空気中において550〜800
℃の範囲で酸化焼成した以外は実験1と同様にして、2
5℃におけるバリスタ電圧■1゜、Aと、非直線係数α
を求めた。
Experiment 3 Next, sample No. 1-6.13-18°25-3 in Table 2
550 to 800 in air.
Experiment 2 was carried out in the same manner as in Experiment 1 except that the oxidation firing was carried out in the range of °C.
Varistor voltage at 5°C■1°, A, and nonlinear coefficient α
I asked for

結果は第2表に示す通りとなった。The results were as shown in Table 2.

※ ※ X ※ ※ ※ 実験3の結果から、空気中における酸化焼成において、
加熱温度が550℃では、バリスタ電圧V 1osAが
0.1〜0.5V程度、非直線係数αも1程度となって
、満足できる電気的特性のものは得られなかった。
※ ※ X ※ ※ ※ From the results of Experiment 3, in oxidation firing in air,
When the heating temperature was 550° C., the varistor voltage V 1osA was about 0.1 to 0.5 V and the nonlinear coefficient α was about 1, so that satisfactory electrical characteristics could not be obtained.

また、空気中における酸化焼成において、加熱温度が8
00℃では、バリスタ電圧V IOmAが300V付近
と高くなり過ぎ、満足できる電気的特性のものは得られ
なかった。
In addition, in oxidation firing in air, the heating temperature is 8.
At 00° C., the varistor voltage V IOmA was too high, around 300 V, and satisfactory electrical characteristics could not be obtained.

従って、空気中における酸化焼成において、加熱温度は
600〜750℃の範囲が好ましい。
Therefore, in the oxidation firing in air, the heating temperature is preferably in the range of 600 to 750°C.

実験4 第3表の試料No7〜12.19〜24.31〜36に
示す組成の成形体を先に酸化性雰囲気中において115
0℃で加熱して酸化焼成した以外は実験lと同様にして
電圧非直線磁器組成物を形成し、この電圧非直線磁器組
成物の25℃におけるバリスタ電圧と非直線係数aを求
めた。
Experiment 4 Sample Nos. 7 to 12.19 to 24.31 to 36 in Table 3 were first placed in an oxidizing atmosphere at 115%
A voltage nonlinear porcelain composition was formed in the same manner as in Experiment 1 except that it was heated at 0°C and oxidized and fired, and the varistor voltage and nonlinearity coefficient a at 25°C of this voltage nonlinear porcelain composition were determined.

結果は第3表に示す通りとなった。The results were as shown in Table 3.

※ ※ ※ × × ※ 上記の結果は、実験1および実験3とほぼ同等になって
おり、成形体を還元焼成させる前にあらかじめ酸化させ
ておいても同様の結果が得られることがわかる。
* * * × × * The above results are almost the same as Experiments 1 and 3, and it can be seen that similar results can be obtained even if the compact is oxidized in advance before reduction firing.

[発明の効果] 本発明によれば、コストの安い酸化亜鉛系の材料を使用
して、バリスタ電圧の低い電圧非直線磁器組成物を得る
ことができるという効果がある。
[Effects of the Invention] According to the present invention, there is an effect that a voltage nonlinear ceramic composition with a low varistor voltage can be obtained using an inexpensive zinc oxide-based material.

Claims (3)

【特許請求の範囲】[Claims] 1.酸化亜鉛を主成分とし、副成分として少なくとも1
種以上の金属酸化物を含有する組成物を焼成してなる焼
結体であって、この焼結体は、還元されて半導体の状態
にある半導体部と、この半導体部の上に所定の厚さで被
覆形成された酸化層とからなる電圧非直線磁器組成物。
1. Contains zinc oxide as a main component and at least 1 as a subcomponent
This sintered body is formed by firing a composition containing at least one metal oxide, and this sintered body includes a semiconductor portion that has been reduced to a semiconductor state, and a predetermined thickness formed on the semiconductor portion. A voltage non-linear porcelain composition comprising an oxide layer coated with an oxidized layer.
2.酸化亜鉛を主成分とし、副成分として少なくとも1
種以上の金属酸化物を含有する組成物を、還元性雰囲気
中において加熱して半導体化させ、次に酸化性雰囲気中
において加熱して表面を酸化させることを特徴とする電
圧非直線磁器組成物の製造方法。
2. Contains zinc oxide as a main component and at least 1 as a subcomponent
A voltage nonlinear ceramic composition characterized in that a composition containing one or more metal oxides is heated in a reducing atmosphere to convert it into a semiconductor, and then heated in an oxidizing atmosphere to oxidize the surface. manufacturing method.
3.酸化亜鉛を主成分とし、副成分として少なくとも1
種以上の金属酸化物を含有する組成物を、酸化性雰囲気
中において加熱して酸化させ、次に、還元性雰囲気中に
おいて加熱して半導体化させ、次に酸化性雰囲気中にお
いて加熱して表面を再酸化させることを特徴とする電圧
非直線磁器組成物の製造方法。
3. Contains zinc oxide as a main component and at least 1 as a subcomponent
A composition containing one or more metal oxides is heated in an oxidizing atmosphere to oxidize it, then heated in a reducing atmosphere to convert it into a semiconductor, and then heated in an oxidizing atmosphere to form a surface. A method for producing a voltage nonlinear porcelain composition, characterized by reoxidizing the composition.
JP2076770A 1990-03-28 1990-03-28 Voltage nonlinear porcelain composition and method for producing the same Expired - Fee Related JPH0648642B2 (en)

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Publication Number Publication Date
JPH03278402A true JPH03278402A (en) 1991-12-10
JPH0648642B2 JPH0648642B2 (en) 1994-06-22

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011216877A (en) * 2010-03-17 2011-10-27 Panasonic Corp Laminated varistor and manufacturing method of the same

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011216877A (en) * 2010-03-17 2011-10-27 Panasonic Corp Laminated varistor and manufacturing method of the same

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JPH0648642B2 (en) 1994-06-22

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