JPH0142601B2 - - Google Patents
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- Publication number
- JPH0142601B2 JPH0142601B2 JP58002520A JP252083A JPH0142601B2 JP H0142601 B2 JPH0142601 B2 JP H0142601B2 JP 58002520 A JP58002520 A JP 58002520A JP 252083 A JP252083 A JP 252083A JP H0142601 B2 JPH0142601 B2 JP H0142601B2
- Authority
- JP
- Japan
- Prior art keywords
- zinc oxide
- lead titanate
- particles
- mol
- added
- 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.)
- Expired
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- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 184
- 239000011787 zinc oxide Substances 0.000 claims description 89
- 239000002245 particle Substances 0.000 claims description 75
- NKZSPGSOXYXWQA-UHFFFAOYSA-N dioxido(oxo)titanium;lead(2+) Chemical compound [Pb+2].[O-][Ti]([O-])=O NKZSPGSOXYXWQA-UHFFFAOYSA-N 0.000 claims description 74
- 239000000203 mixture Substances 0.000 claims description 31
- 238000005245 sintering Methods 0.000 claims description 14
- 239000000843 powder Substances 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 6
- 229910000416 bismuth oxide Inorganic materials 0.000 claims description 5
- TYIXMATWDRGMPF-UHFFFAOYSA-N dibismuth;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Bi+3].[Bi+3] TYIXMATWDRGMPF-UHFFFAOYSA-N 0.000 claims description 5
- 239000007921 spray Substances 0.000 claims description 4
- 229910044991 metal oxide Inorganic materials 0.000 claims description 3
- 150000004706 metal oxides Chemical class 0.000 claims description 3
- 238000005469 granulation Methods 0.000 claims description 2
- 230000003179 granulation Effects 0.000 claims description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims 1
- 230000001590 oxidative effect Effects 0.000 claims 1
- 239000011701 zinc Substances 0.000 claims 1
- 239000013078 crystal Substances 0.000 description 26
- 238000010586 diagram Methods 0.000 description 12
- 230000000630 rising effect Effects 0.000 description 9
- 229910015902 Bi 2 O 3 Inorganic materials 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000001354 calcination Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 238000000465 moulding Methods 0.000 description 4
- 238000000354 decomposition reaction Methods 0.000 description 3
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 3
- 239000012798 spherical particle Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(II) oxide Inorganic materials [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 2
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- QPLDLSVMHZLSFG-UHFFFAOYSA-N CuO Inorganic materials [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 229910002637 Pr6O11 Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- ADCOVFLJGNWWNZ-UHFFFAOYSA-N antimony trioxide Inorganic materials O=[Sb]O[Sb]=O ADCOVFLJGNWWNZ-UHFFFAOYSA-N 0.000 description 1
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Inorganic materials [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 description 1
- -1 bismuth Chemical class 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum oxide Inorganic materials [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 description 1
- YEXPOXQUZXUXJW-UHFFFAOYSA-N lead(II) oxide Inorganic materials [Pb]=O YEXPOXQUZXUXJW-UHFFFAOYSA-N 0.000 description 1
- VASIZKWUTCETSD-UHFFFAOYSA-N manganese(II) oxide Inorganic materials [Mn]=O VASIZKWUTCETSD-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- KTUFCUMIWABKDW-UHFFFAOYSA-N oxo(oxolanthaniooxy)lanthanum Chemical compound O=[La]O[La]=O KTUFCUMIWABKDW-UHFFFAOYSA-N 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 229910000108 silver(I,III) oxide Inorganic materials 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- IATRAKWUXMZMIY-UHFFFAOYSA-N strontium oxide Inorganic materials [O-2].[Sr+2] IATRAKWUXMZMIY-UHFFFAOYSA-N 0.000 description 1
- YEAUATLBSVJFOY-UHFFFAOYSA-N tetraantimony hexaoxide Chemical compound O1[Sb](O2)O[Sb]3O[Sb]1O[Sb]2O3 YEAUATLBSVJFOY-UHFFFAOYSA-N 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Landscapes
- Thermistors And Varistors (AREA)
- Compositions Of Oxide Ceramics (AREA)
Description
【発明の詳細な説明】
本発明は酸化亜鉛を主成分とした低電圧用のバ
リスタおよびその製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a low voltage varistor containing zinc oxide as a main component and a method for manufacturing the same.
従来酸化亜鉛を主成分としこれにBi2O3、
MgO、Cr2O3、Fe2O3、Sb2O3、CoO、MnO、
NiOなどの電圧敏感性酸化物および電導性酸化物
を加えた組成を成形焼結してなる酸化亜鉛系バリ
スタはそのすぐれた非直線性のために広く用いら
れている。これらの酸化亜鉛系バリスタでは焼結
体厚さ１mmにおける立上り電圧をV1ｍＡ／mmと
し種々の立上り電圧のものが製造されているが、
この立上り電圧は焼結体中の酸化亜鉛を主成分と
する結晶粒の大きさによつて決まる。すなわち低
い立上り電圧を得るためには結晶粒を大きく成長
させることが必要であり、逆に高い立上り電圧を
得るためには結晶粒の成長を抑え、小さな結晶粒
から構成することが必要である。前記酸化亜鉛を
主成分としBi2O3、MgO、Cr2O3、Fe2O3、
Sb2O3、CoO、MnO、NiOなどを加えてなる酸化
亜鉛系バリスタでは結晶粒の大きさが15μｍ程度
であり、立上り電圧は組成により約80〜300Vで
ある。また前記組成からSb2O3を除いたものは結
晶粒の大きさが50μｍ程度、立上り電圧は20〜
40V程度となることも知られている。近年とくに
酸化亜鉛系バリスタの低電圧化の要求が強まり前
記結晶粒の大きなものを含む酸化亜鉛系バリスタ
を得ることが重要な課題となつてきた。この大き
な結晶粒を得る手段としてたとえば特公昭56−
11203号公報に提案された技術がある。これは酸
化亜鉛99.9〜99.5モル％とBaOまたはSrO0.1〜0.5
モル％を混合したのち仮焼し加水熱分解を行つて
70μｍ程度の結晶粒を得、該結晶粒を酸化亜鉛を
主成分とする粉末に0.1〜60重量％添加混合した
のち焼結してなるものである。しかしながらこの
ように加水熱分解によつて結晶粒を得るには前記
酸化亜鉛にBaOまたはSrOを調合しバインダを加
えて成形し、1300℃程度の高温で仮焼し粉砕した
のち加水熱分解しなければならず、工程数が非常
に多くなる欠点がある。また成形後の仮焼温度を
高くしないと大きな結晶粒が得られず、たとえば
結晶粒の大きさ70μｍのものを得るには1300℃程
度の高い仮焼温度を要し、温度管理ならびにこれ
にともなう焼結炉の材料の選択などの技術的、価
格的問題点もあつた。また特性的にもこの結晶粒
を得るための仮焼温度が高いと結晶粒自体の成長
が進んでしまうため活性度が小さくなり、かつこ
の結晶粒を酸化亜鉛を主成分とするものに加え混
合焼結して焼結体を得るときの焼結温度と前記仮
焼温度とが近くなるので結晶粒の成長は限界近く
なり、したがつて焼結体を得るときの焼結過程に
おいて結晶粒がほとんど成長せず焼結後も前記加
水熱分解により得た結晶粒とあまり変わらない大
きさのものしか得られないという欠点を有してい
た。 Conventionally, zinc oxide is the main component, and Bi 2 O 3 ,
MgO, Cr2O3 , Fe2O3 , Sb2O3 , CoO , MnO ,
Zinc oxide-based varistors, which are formed by molding and sintering a composition containing voltage-sensitive oxides such as NiO and conductive oxides, are widely used because of their excellent nonlinearity. These zinc oxide-based varistors have a rising voltage of V1mA/mm when the thickness of the sintered body is 1 mm, and various types of rising voltage are manufactured.
This rising voltage is determined by the size of crystal grains whose main component is zinc oxide in the sintered body. That is, in order to obtain a low rising voltage, it is necessary to grow large crystal grains, and conversely, in order to obtain a high rising voltage, it is necessary to suppress the growth of crystal grains and to construct the crystal grains from small crystal grains. The above-mentioned zinc oxide is the main component, and Bi 2 O 3 , MgO, Cr 2 O 3 , Fe 2 O 3 ,
In zinc oxide-based varistors made by adding Sb 2 O 3 , CoO, MnO, NiO, etc., the crystal grain size is about 15 μm, and the rise voltage is about 80 to 300 V depending on the composition. In addition, when Sb 2 O 3 is removed from the above composition, the crystal grain size is about 50 μm, and the rise voltage is 20 ~
It is also known that the voltage is around 40V. In recent years, there has been a particularly strong demand for lower voltages for zinc oxide-based varistors, and it has become an important issue to obtain zinc oxide-based varistors containing large crystal grains. As a means of obtaining such large crystal grains, for example,
There is a technique proposed in Publication No. 11203. This is zinc oxide 99.9-99.5 mol% and BaO or SrO 0.1-0.5
After mixing the mol%, calcining and hydrothermal decomposition are performed.
Crystal grains of approximately 70 μm are obtained, and the crystal grains are added and mixed in a powder containing zinc oxide in an amount of 0.1 to 60% by weight, and then sintered. However, in order to obtain crystal grains through hydrothermal decomposition, it is necessary to mix BaO or SrO with the zinc oxide, add a binder, shape it, calcinate it at a high temperature of about 1300°C, crush it, and then hydropyrolyze it. However, there is a drawback that the number of steps is extremely large. In addition, large crystal grains cannot be obtained unless the calcination temperature after molding is high; for example, to obtain crystal grains with a size of 70 μm, a high calcination temperature of about 1300°C is required, and temperature control and accompanying There were also technical and cost issues such as the selection of materials for the sintering furnace. Also, in terms of characteristics, if the calcination temperature to obtain these crystal grains is high, the growth of the crystal grains themselves will progress, resulting in a decrease in activity. Since the sintering temperature when sintering to obtain a sintered body and the above-mentioned calcination temperature are close to each other, the growth of crystal grains is close to its limit, and therefore, the crystal grains are It has the disadvantage that it hardly grows, and even after sintering, only crystal grains with a size not much different from those obtained by the hydrothermal decomposition can be obtained.
本発明は上記の点に鑑みてなされたもので、酸
化亜鉛とチタン酸鉛と造粒して得た粒子を、酸化
亜鉛を主成分としこれに少なくとも酸化ビスマス
を加えた粉粒中に添加混合して焼結することによ
り前記粒子を焼結体内部に分散して位置させ、こ
れを核として結晶粒の成長を図るもので、これに
よつて焼結体内部に大きな結晶粒を配しバリスタ
の低電圧化を図ることを目的としたものである。
以下本発明の詳細を実施例によつて説明する。 The present invention was made in view of the above-mentioned points, and particles obtained by granulating zinc oxide and lead titanate are added and mixed into powder particles containing zinc oxide as a main component and at least bismuth oxide added thereto. By sintering the particles, the particles are dispersed and located inside the sintered body, and the crystal grains are grown using these as nuclei. By this, large crystal grains are arranged inside the sintered body and the varistor is formed. The purpose of this is to reduce the voltage.
The details of the present invention will be explained below with reference to Examples.
実施例 １
酸化亜鉛粉末にチタン酸鉛粉末をそれぞれ
0.003％モル％、0.01モル％、0.03モル％、0.1モ
ル％、0.3モル％、1.0モル％、3.0モル％添加混合
して７種の酸化亜鉛＋チタン酸鉛の混合粉末を
得、これにバインダと水を加えて混合する。これ
をスプレードライヤに入れて造粒すると前記混合
粉末に加えた水が蒸発した球状粒子を得ることが
できる。この球状粒子はその粒径が約３〜200μ
ｍの大さを有するが、60〜120μｍの粒子がもつ
とも多く20μｍ程度の粒子は非常に少ない。前記
酸化亜鉛＋チタン酸鉛による７種の粒子を篩で選
別して平均粒径100μｍの酸化亜鉛＋チタン酸鉛
の粒子を得、これを酸化亜鉛94.5モル％＋MgO3
モル％＋Bi2O30.5モル％＋CoO1.0モル％＋
MnO0.5モル％＋NiO0.5モル％からなる主組成に
対しそれぞれ0.1重量％、0.3重量％、10重量％、
30重量％、60重量％添加混合し、これを成形した
のち1100〜1400℃の温度で１〜８時間焼結した焼
結体の立上り電圧を酸化亜鉛へのチタン酸鉛の添
加量との関連にについて表わしたのが第１図であ
り同じく非直線係数ａを表わしたのが第２図であ
る。いずれも曲線Ａは主組成に対する酸化亜鉛＋
チタン酸鉛粒子の添加量が0.1重量％の場合、同
じく曲線Ｂは0.3重量％、曲線Ｃは10重量％、曲
線Ｄは30重量％、曲線Ｅは60重量％の場合であ
る。また第３図には平均粒径100μｍの酸化亜鉛
＋チタン酸鉛粒子を用い、前記主組成に対するこ
の粒子の添加量と立上り電圧との関係を示す曲線
図、第４図はこの粒子の添加量と非直線係数との
関係を示す曲線図であるが、いずれも曲線Ｆは酸
化亜鉛＋チタン酸鉛粒子の酸化亜鉛に対するチタ
ン酸鉛の添加量が0.003モル％の場合、曲線Ｇは
0.01モル％、曲線Ｈは0.1モル％、曲線Ｉは1.0モ
ル％、曲線Ｊは3.0モル％の場合を示したもので
ある。さらに第５図には酸化亜鉛に対しチタン酸
鉛を0.1モル％添加した酸化亜鉛＋チタン酸鉛粒
子を前記主組成に対し10重量％添加したときの酸
化亜鉛＋チタン酸鉛粒子の大きさと立上り電圧と
の関係を示す曲線図であり、第６図は粒子の大き
さと非直線係数との関係を示す曲線図である。こ
の結果から明らかなように第１図の立上り電圧で
は酸化亜鉛に添加するチタン酸鉛の量は曲線Ａを
除き0.01モル％以上が良好であるが、第２図の非
直線係数では曲線Ｅを除きチタン酸鉛添加量1.0
モル％までは良好でありこれを越えると急激に低
下するという結果を示している。この第１図およ
び第２図の結果から酸化亜鉛に添加するチタン酸
鉛の量は0.01〜1.0モル％が良好であり、かつこ
の酸化亜鉛＋チタン酸鉛粒子を主組成に添加する
量は0.3〜30重量％が良好である。そして第３図
および第４図でも酸化亜鉛＋チタン酸鉛粒子中の
チタン酸鉛添加量による特性への影響は曲線Ｆが
第３図の立上り電圧特性が劣つており、また第４
図の曲線Ｊが非直線係数が劣つていることを示し
ている。そして第３図では主組成に対する酸化亜
鉛＋チタン酸鉛粒子の添加量では0.3重量％から
顕著な効果を示し、第４図では30重量％までは良
好だがこれを越えると急激に劣化することを示し
ている。したがつて主組成に対する酸化亜鉛＋チ
タン酸鉛粒子の添加量は0.3〜30重量％が良好で
あり、かつ前述のように曲線ＦおよびＪを除外し
た曲線Ｇ，Ｈ，Ｉが良好な結果を示していること
から酸化亜鉛に対するチタン酸鉛の添加量は0.01
〜1.0モル％である。したがつてこの範囲は第１
図および第２図と全く同一な結果を示している。Example 1 Adding lead titanate powder to zinc oxide powder
0.003% mol%, 0.01 mol%, 0.03 mol%, 0.1 mol%, 0.3 mol%, 1.0 mol%, and 3.0 mol% were added and mixed to obtain seven types of mixed powder of zinc oxide + lead titanate, and a binder was added to this. Add water and mix. When this is placed in a spray dryer and granulated, spherical particles in which the water added to the mixed powder has evaporated can be obtained. These spherical particles have a particle size of approximately 3 to 200μ.
It has a size of m, but there are many particles of 60 to 120 μm, and very few particles of about 20 μm. The seven types of particles of zinc oxide + lead titanate were sorted with a sieve to obtain particles of zinc oxide + lead titanate with an average particle size of 100 μm, which were then mixed with 94.5 mol% zinc oxide + MgO3.
Mol% + Bi 2 O 3 0.5 mol% + CoO 1.0 mol% +
0.1% by weight, 0.3% by weight, 10% by weight, respectively, for the main composition consisting of 0.5 mol% MnO + 0.5 mol% NiO,
The relationship between the rise voltage of a sintered body obtained by adding 30% by weight and 60% by weight, molding it, and sintering it at a temperature of 1100 to 1400°C for 1 to 8 hours is related to the amount of lead titanate added to zinc oxide. FIG. 1 shows the nonlinear coefficient a, and FIG. 2 shows the nonlinear coefficient a. In both cases, curve A is zinc oxide +
When the amount of lead titanate particles added is 0.1% by weight, curve B is 0.3% by weight, curve C is 10% by weight, curve D is 30% by weight, and curve E is 60% by weight. Furthermore, Figure 3 is a curve diagram showing the relationship between the amount of these particles added to the main composition and the rise voltage using zinc oxide + lead titanate particles with an average particle size of 100 μm, and Figure 4 is a curve diagram showing the relationship between the amount of these particles added and the rise voltage. 2 is a curve diagram showing the relationship between
0.01 mol%, curve H is 0.1 mol%, curve I is 1.0 mol%, and curve J is 3.0 mol%. Furthermore, Figure 5 shows the size and rise of zinc oxide + lead titanate particles when 10% by weight of zinc oxide + lead titanate particles is added to the main composition, with 0.1 mol% of lead titanate added to zinc oxide. FIG. 6 is a curve diagram showing the relationship with voltage, and FIG. 6 is a curve diagram showing the relationship between particle size and nonlinear coefficient. As is clear from this result, for the rise voltage in Figure 1, the amount of lead titanate added to zinc oxide is good at 0.01 mol% or more, except for curve A, but for the nonlinear coefficient in Figure 2, curve E Excluding lead titanate addition amount 1.0
The results show that the content is good up to mol % and rapidly decreases beyond this range. From the results shown in Fig. 1 and Fig. 2, the amount of lead titanate added to zinc oxide is preferably 0.01 to 1.0 mol%, and the amount of zinc oxide + lead titanate particles added to the main composition is 0.3%. ~30% by weight is good. Also in Figures 3 and 4, the effect of the amount of lead titanate added in the zinc oxide + lead titanate particles on the characteristics is that curve F has inferior rise voltage characteristics in Figure 3, and
Curve J in the figure shows that the nonlinear coefficient is inferior. Figure 3 shows that the amount of zinc oxide + lead titanate particles added to the main composition shows a remarkable effect from 0.3% by weight, and Figure 4 shows that it is good up to 30% by weight, but deteriorates rapidly beyond this. It shows. Therefore, the amount of zinc oxide + lead titanate particles added to the main composition is preferably 0.3 to 30% by weight, and as mentioned above, curves G, H, and I excluding curves F and J give good results. As shown, the amount of lead titanate added to zinc oxide is 0.01
~1.0 mol%. Therefore, this range is the first
The results are exactly the same as those shown in Fig. 2 and Fig. 2.
さらに酸化亜鉛＋チタン酸鉛の粒子径と立上り
電圧および非直線係数との関係を第５図および第
６図に示す。なお試料は酸化亜鉛に添加するチタ
ン酸鉛量を0.1モル％とし上記実施例と同じ組成
からなる主組成に対し酸化亜鉛＋チタン酸鉛を10
重量％添加混合した粒子を用いたものである。第
５図および第６図において従来とあるのは主組成
に直接実施例と同じ量の酸化亜鉛とチタン酸鉛粉
末を添加し、これらを混合して1100〜1400℃の温
度で１〜８時間いつしよに焼結した場合を示し酸
化亜鉛＋チタン酸鉛の造粒工程を省いたものであ
る。これによればスプレードライヤで造粒した酸
化亜鉛＋チタン酸鉛粒子の平均粒径が10μｍでは
非直線係数が従来と変化なく、かつ立上り電圧
V1ｍＡ／mmの従来の39Vから29Vに低下し非常に
低電圧のバリスタを得られることは明白であり、
平均粒径が大となるにしたがつて立上り電圧は急
激な低下を示す。しかし非直線係数は従来30に対
し平均粒径100μｍを越えると急激に低下しはじ
め、200μｍでは22を示しこの値は十分使用でき
る値であるが、300μｍではさらに低下して10と
なり使用できない数値となる。以上のことから酸
化亜鉛＋チタン酸鉛を造粒したときの粒径は10〜
200μｍが適当な範囲と定めることができる。 Furthermore, the relationship between the particle diameter of zinc oxide + lead titanate, the rise voltage, and the nonlinear coefficient is shown in FIGS. 5 and 6. The sample was made by adding 0.1 mol% of lead titanate to zinc oxide, and the main composition was the same as that of the above example, but 10% of zinc oxide + lead titanate was used.
Particles added and mixed in weight percent are used. In Figures 5 and 6, the conventional method is to directly add the same amount of zinc oxide and lead titanate powder to the main composition as in the example, mix them and heat them at a temperature of 1100 to 1400°C for 1 to 8 hours. This shows the case of sintering as usual, and the granulation process of zinc oxide + lead titanate is omitted. According to this, when the average particle size of zinc oxide + lead titanate particles granulated with a spray dryer is 10 μm, the nonlinear coefficient remains unchanged from the conventional one, and the rise voltage
It is clear that V1mA/mm can be lowered from the conventional 39V to 29V, resulting in a very low voltage varistor.
As the average particle size increases, the rise voltage shows a rapid decrease. However, the nonlinear coefficient starts to decrease rapidly compared to the conventional 30 when the average particle size exceeds 100 μm, and at 200 μm it reaches 22, which is a sufficiently usable value, but at 300 μm it decreases further to 10, which is an unusable value. Become. From the above, when zinc oxide + lead titanate is granulated, the particle size is 10~
200 μm can be determined as an appropriate range.
この結果から酸化亜鉛粉末に対し0.01〜1.0モ
ル％のチタン酸鉛を添加して造粒し平均粒径10〜
200μｍの酸化亜鉛＋チタン酸鉛粒子を得、これ
を酸化亜鉛＋MgO＋Bi2O3＋CoO＋MnO＋NiO
からなる主組成に対し0.3〜30重量％添加して混
合粒子とし、ともに焼結することによつて立上り
電圧や非直線係数などの特性の優れた低電圧用バ
リスタを得ることができる。 Based on this result, we added 0.01 to 1.0 mol% of lead titanate to zinc oxide powder and granulated it with an average particle size of 10 to 10.
200 μm zinc oxide + lead titanate particles were obtained, and these were mixed into zinc oxide + MgO + Bi 2 O 3 + CoO + MnO + NiO.
By adding 0.3 to 30% by weight to the main composition consisting of 0.3 to 30% by weight to form mixed particles and sintering them together, a low voltage varistor with excellent characteristics such as rise voltage and nonlinear coefficient can be obtained.
実施例 ２
前記実施例１では主組成として酸化亜鉛＋
MgO＋Bi2O3＋CoO＋MnO＋NiOからなるもの
を使用した場合について述べたが、この実施例２
ではこれにSb2O3およびCr2O3を加えて主組成と
した場合について述べる。Sb2O3やCr2O3は酸化
亜鉛の結晶粒成長を助長させるビスマスなどの低
融点金属やこれらの酸化物の中へ早期に拡散する
ので酸化亜鉛の粒成長を阻害する性質を有してい
る。したがつてSb2O3やCr2O3を含む酸化亜鉛を
主成分とするバリスタでは酸化亜鉛の結晶粒成長
が望めず結晶が小さくなるので比較的高電圧用に
用いられ低電圧用には不適とされているものであ
る。まず酸化亜鉛粉末にチタン酸鉛粉末をそれぞ
れ0.003モル％、0.01モル％、0.03モル％、0.1モ
ル％、0.3モル％、3.0モル％添加混合してスプレ
ードライヤで造粒し７種の酸化亜鉛＋チタン酸鉛
粒子を得、以下実施例１と同様にして平均粒径
100μｍの酸化亜鉛＋チタン酸鉛の球状粒子を得
た。この粒子を酸化亜鉛94モル％＋MgO3モル％
＋Bi2O30.5モル％＋CoO1.0モル％＋MnO0.5モル
％＋NiO0.5モル％＋Sb2O30.3モル％＋Cr2O30.2
モル％からなる主組成に対し、0.1重量％、0.3重
量％、10重量％、30重量％、60重量％をそれぞれ
添加混合してこれを成形したのち1100〜1400℃の
温度で１〜８時間焼結したときの立上り電圧を酸
化亜鉛へのチタン酸鉛の添加量との関連において
第７図、同じく非直線係数を第８図に示した。い
ずれも曲線Ｋは主組成に対する酸化亜鉛＋チタン
酸鉛粒子の添加量が0.1重量％の場合、曲線Ｌは
0.3重量％、曲線Ｍは10重量％、曲線Ｎは30重量
％、曲線Ｏは60重量％の場合を示す。また第９図
には平均粒径100μｍの酸化亜鉛＋チタン酸鉛粒
子を用い前記主組成に対するこの粒子の添加量と
立上り電圧との関係を示す曲線図を、そして第１
０図にはこの粒子の添加量と非直線係数との関係
を示す曲線図を示した。なお曲線Ｐは酸化亜鉛＋
チタン酸鉛粒子の酸化亜鉛に対するチタン酸鉛の
添加量が0.003モル％の場合、曲線Ｑは0.01モル
％、曲線Ｒは0.1モル％、曲線Ｓは1.0モル％、曲
線Ｔは3.0モル％の場合を示したものである。そ
して第１１図には酸化亜鉛に対しチタン酸鉛を
0.1モル％添加した酸化亜鉛＋チタン酸鉛粒子を
主組成に対し10重量％添加したときの酸化亜鉛＋
チタン酸鉛粒子の大きさと立上り電圧との関係を
示す曲線図であり、第１２図は粒子の大きさと非
直線係数との関係を示す曲線図である。なおそれ
ぞれの焼結は1100〜1400℃の温度で１〜８時間行
つた。Example 2 In Example 1, the main composition was zinc oxide +
Although we have described the case where MgO + Bi 2 O 3 + CoO + MnO + NiO is used, this Example 2
Now, we will discuss the case where Sb 2 O 3 and Cr 2 O 3 are added to this as the main composition. Sb 2 O 3 and Cr 2 O 3 have the property of inhibiting the grain growth of zinc oxide because they quickly diffuse into low melting point metals such as bismuth, which promote grain growth of zinc oxide, and these oxides. ing. Therefore, in varistors whose main component is zinc oxide containing Sb 2 O 3 or Cr 2 O 3 , crystal grain growth of zinc oxide cannot be expected and the crystals become small, so they are used for relatively high voltage applications and are not used for low voltage applications. It is considered inappropriate. First, 0.003 mol%, 0.01 mol%, 0.03 mol%, 0.1 mol%, 0.3 mol%, and 3.0 mol% of lead titanate powder were added and mixed to zinc oxide powder and granulated with a spray dryer. Lead titanate particles were obtained, and the average particle size was determined in the same manner as in Example 1.
Spherical particles of zinc oxide + lead titanate with a diameter of 100 μm were obtained. These particles are 94 mol% zinc oxide + 3 mol% MgO
+Bi 2 O 3 0.5 mol% + CoO 1.0 mol% + MnO 0.5 mol% + NiO 0.5 mol% + Sb 2 O 3 0.3 mol% + Cr 2 O 3 0.2
To the main composition consisting of mol%, 0.1% by weight, 0.3% by weight, 10% by weight, 30% by weight, and 60% by weight are added and mixed, and then molded and then heated at a temperature of 1100 to 1400°C for 1 to 8 hours. The rise voltage upon sintering is shown in FIG. 7 in relation to the amount of lead titanate added to zinc oxide, and the nonlinear coefficient is shown in FIG. 8. In both cases, curve K shows that when the amount of zinc oxide + lead titanate particles added to the main composition is 0.1% by weight, curve L shows that
0.3% by weight, curve M shows 10% by weight, curve N shows 30% by weight, and curve O shows 60% by weight. Further, FIG. 9 shows a curve diagram showing the relationship between the amount of these particles added to the main composition and the rise voltage using zinc oxide + lead titanate particles with an average particle size of 100 μm, and
Figure 0 shows a curve diagram showing the relationship between the amount of particles added and the nonlinear coefficient. Curve P is zinc oxide +
When the amount of lead titanate added to the zinc oxide in the lead titanate particles is 0.003 mol%, curve Q is 0.01 mol%, curve R is 0.1 mol%, curve S is 1.0 mol%, and curve T is 3.0 mol%. This is what is shown. Figure 11 shows lead titanate compared to zinc oxide.
Zinc oxide with 0.1 mol% added + zinc oxide + lead titanate particles added with 10% by weight based on the main composition
FIG. 12 is a curve diagram showing the relationship between the size of lead titanate particles and the rising voltage, and FIG. 12 is a curve diagram showing the relationship between the particle size and the nonlinear coefficient. Note that each sintering was performed at a temperature of 1100 to 1400°C for 1 to 8 hours.
これらの結果から明らかなように第７図および
第８図に示した立上り電圧と非直線係数は実施例
１の第１図・第２図より顕著ではないが、曲線Ｋ
およびＯを除き酸化亜鉛に添加するチタン酸鉛の
混合量が0.01〜1.0モル％の範囲で良好である。
したがつて第７図および第８図の結果から酸化亜
鉛に添加するチタン酸鉛の量は0.01〜1.0モル％
で、かつこの酸化亜鉛＋チタン酸鉛粒子を主組成
に添加する量は0.3〜30重量％の範囲が良好であ
る。この範囲が特性上良好な結果を示すことは第
９図および第１０図からも確認できる。そして実
施例１と同様、酸化亜鉛＋チタン酸鉛粒子の大き
さと立上り電圧および非直線係数との関係を第１
１図および第１２図に示す。試料は酸化亜鉛に添
加するチタン酸鉛量を0.1モル％とし主組成に対
し酸化亜鉛＋チタン酸鉛粒子を10重量％添加した
ものを用いた。図において従来とあるのは主組成
に直接該実施例と同じ量の酸化亜鉛とチタン酸鉛
粉末を添加混合して焼結した場合を示したもので
ある。この結果立上り電圧および非直線係数とも
絶対値は大きいものの実施例１と同様の特性傾向
を示しており、酸化亜鉛＋チタン酸鉛粒子の平均
粒径が10〜200μｍが適当な範囲とすることがで
きる。 As is clear from these results, the rising voltage and nonlinear coefficient shown in FIGS. 7 and 8 are not as remarkable as those in FIGS. 1 and 2 of Example 1, but the curve K
The mixed amount of lead titanate added to zinc oxide excluding O and O is preferably in the range of 0.01 to 1.0 mol%.
Therefore, from the results shown in Figures 7 and 8, the amount of lead titanate added to zinc oxide is 0.01 to 1.0 mol%.
And the amount of zinc oxide + lead titanate particles added to the main composition is preferably in the range of 0.3 to 30% by weight. It can be confirmed from FIGS. 9 and 10 that this range shows good results in terms of characteristics. As in Example 1, the relationship between the size of the zinc oxide + lead titanate particles, the rising voltage, and the nonlinear coefficient was determined as follows.
1 and 12. The sample used was one in which the amount of lead titanate added to zinc oxide was 0.1 mol%, and 10% by weight of zinc oxide + lead titanate particles was added to the main composition. In the figure, "conventional" indicates the case where zinc oxide and lead titanate powder were added and mixed directly to the main composition in the same amounts as in the embodiment and sintered. As a result, although the absolute values of both the rise voltage and the nonlinear coefficient are large, they show the same tendency of characteristics as in Example 1, and the average particle size of the zinc oxide + lead titanate particles should be in an appropriate range of 10 to 200 μm. can.
この実施例２では酸化亜鉛粉末に対し0.01〜
1.0モル％のチタン酸鉛を添加して造粒し平均粒
径10〜200μｍの酸化亜鉛＋チタン酸鉛粒子を得、
これを酸化亜鉛＋MgO＋Bi2O3＋CoO＋MnO＋
NiO＋Sb2O3＋Cr2O3からなる主組成に対し0.3〜
30重量％添加混合し、これをいつしよに焼結する
ことによつて立上り電圧や非直線係数特性の優れ
たバリスタを得ることができる。したがつて酸化
亜鉛の結晶粒成長を阻害するSb2O3やCr2O3を含
む主組成に酸化亜鉛＋チタン酸鉛粒子を添加した
場合でも結晶粒は成長するので低電圧化できる効
果を有する。 In this Example 2, 0.01~
Add 1.0 mol% lead titanate and granulate to obtain zinc oxide + lead titanate particles with an average particle size of 10 to 200 μm,
This is zinc oxide + MgO + Bi 2 O 3 + CoO + MnO +
0.3 to main composition consisting of NiO + Sb 2 O 3 + Cr 2 O 3
By adding and mixing 30% by weight and sintering this at the same time, a varistor with excellent rise voltage and nonlinear coefficient characteristics can be obtained. Therefore, even if zinc oxide + lead titanate particles are added to the main composition, which contains Sb 2 O 3 and Cr 2 O 3 , which inhibit the growth of zinc oxide crystal grains, the crystal grains will grow, so the effect of lowering the voltage can be achieved. have
以上述べたように本発明によればあらかじめ酸
化亜鉛＋チタン酸鉛粉末を造粒したのちこれを酸
化亜鉛を主とする主組成に添加混合−成形し焼結
してバリスタを得るもので、このバリスタは結晶
粒径が大きいので非直線係数を低下させずに立上
り電圧を低下させる特性を有し低電圧用に適する
ものである。なお実施例１および実施例２で酸化
亜鉛粉末に対するチタン酸鉛粉末の混合比が0.01
〜1.0モル％、主組成に添加する酸化亜鉛＋チタ
ン酸鉛粒子量が0.3〜30重量％の範囲が良好であ
る旨述べたが、焼結したバリスタ中に含まれるチ
タン酸鉛量はPbTiO3の形に換算して0.00003〜
0.3モル％となる。また実施例では主組成として
酸化亜鉛、酸化ビスマスにほかMgO、CoO、
MnO、NiO、Sb2O3、Cr2O3を添加した場合につ
いて述べたが、その他の金属酸化物たとえば
SiO2、CuO、Al2O3、BaO、CaO、SrO、PbO、
SnO2、Ag2O、TiO2、ZrO2、La2O3、Pr6O11、
Fe2O3、B2O3などを添加してもよく、空気中高温
で酸化物になるものならばこれらに限るものでは
ない。しかし本発明は主組成としての酸化亜鉛と
酸化ビスマスとに酸化亜鉛＋チタン酸鉛粒子を加
えた焼結体からなるものでバリスタの低電圧化の
効果を得ることができるものであつて、前記
MgO、CoOなどの金属酸化物はバリスタとして
の特性を向上させる効果は有するが本発明の要旨
たる低電圧化という観点からは必須要件ではな
い。 As described above, according to the present invention, a varistor is obtained by first granulating zinc oxide + lead titanate powder, then adding it to a main composition mainly consisting of zinc oxide, mixing, molding, and sintering. Since the varistor has a large crystal grain size, it has the characteristic of reducing the rising voltage without reducing the nonlinear coefficient, and is suitable for low voltage applications. In Example 1 and Example 2, the mixing ratio of lead titanate powder to zinc oxide powder was 0.01.
~1.0 mol%, and the amount of zinc oxide + lead titanate particles added to the main composition is said to be in the range of 0.3 to 30% by weight, but the amount of lead titanate contained in the sintered varistor is PbTiO 3 Convert to the form of 0.00003~
It becomes 0.3 mol%. In addition to zinc oxide, bismuth oxide, MgO, CoO,
The case where MnO, NiO, Sb 2 O 3 and Cr 2 O 3 are added has been described, but other metal oxides such as
SiO2 , CuO, Al2O3 , BaO, CaO, SrO , PbO,
SnO2 , Ag2O , TiO2 , ZrO2 , La2O3 , Pr6O11 ,
Fe 2 O 3 , B 2 O 3 and the like may be added, but are not limited to these as long as they become oxides at high temperatures in air. However, the present invention is made of a sintered body in which zinc oxide and lead titanate particles are added to zinc oxide and bismuth oxide as the main components, and it is possible to obtain the effect of lowering the voltage of the varistor.
Although metal oxides such as MgO and CoO have the effect of improving the characteristics of a varistor, they are not essential from the viewpoint of lowering the voltage, which is the gist of the present invention.
図面はいずれも本発明および参考例、従来例の
特性を示す曲線図で第１図は酸化亜鉛に対するチ
タン酸鉛の添加量と立上り電圧の関係、第２図は
同じくチタン酸鉛の添加量と非直線係数との関
係、第３図は主組成に対する酸化亜鉛＋チタン酸
鉛粒子の添加量と立上り電圧との関係、第４図は
同じく酸化亜鉛＋チタン酸鉛粒子の添加量と非直
線係数との関係、第５図は酸化亜鉛＋チタン酸鉛
粒子の平均粒径と立上り電圧との関係、第６図は
同じく酸化亜鉛＋チタン酸鉛粒子の平均粒径と非
直線係数との関係、第７図〜第１２図は他の実施
例による特性を示す曲線図であり第７図は酸化亜
鉛に対するチタン酸鉛の添加量と立上り電圧の関
係、第８図は同じくチタン酸鉛の添加量と非直線
係数との関係、第９図は主組成に対する酸化亜鉛
＋チタン酸鉛粒子の添加量と立上り電圧との関
係、第１０図は同じく酸化亜鉛＋チタン酸鉛粒子
の添加量と非直線係数との関係、第１１図は酸化
亜鉛＋チタン酸鉛粒子の平均粒径と立上り電圧と
の関係、第１２図は同じく酸化亜鉛＋チタン酸鉛
粒子の平均粒径と非直線係数ととの関係を示す曲
線図である。
The drawings are curve diagrams showing the characteristics of the present invention, reference examples, and conventional examples. Figure 1 shows the relationship between the amount of lead titanate added to zinc oxide and the rise voltage, and Figure 2 shows the relationship between the amount of lead titanate added and the rise voltage. The relationship with the nonlinear coefficient, Figure 3 shows the relationship between the amount of zinc oxide + lead titanate particles added to the main composition and the rise voltage, and Figure 4 shows the relationship between the amount of zinc oxide + lead titanate particles added and the nonlinear coefficient. Figure 5 shows the relationship between the average particle diameter of zinc oxide + lead titanate particles and the rise voltage, and Figure 6 shows the relationship between the average particle diameter of zinc oxide + lead titanate particles and the nonlinear coefficient. Figures 7 to 12 are curve diagrams showing the characteristics according to other examples. Figure 7 is the relationship between the amount of lead titanate added to zinc oxide and the rise voltage, and Figure 8 is the amount of lead titanate added to zinc oxide. Figure 9 shows the relationship between the amount of zinc oxide + lead titanate particles added to the main composition and the rise voltage, and Figure 10 shows the relationship between the amount of zinc oxide + lead titanate particles added and the nonlinear coefficient. Figure 11 shows the relationship between the average particle diameter of zinc oxide + lead titanate particles and the rise voltage, and Figure 12 shows the relationship between the average particle diameter of zinc oxide + lead titanate particles and the nonlinear coefficient. It is a curve diagram showing a relationship.
Claims (1)
ビスマスとチタン酸鉛を含む数種類の金属酸化物
を添加混合して成形、焼結した焼結体からなるバ
リスタにおいて、前記チタン酸鉛の添加量が
PbTiO3の形に換算して0.00003〜0.3モル％であ
ることを特徴とするバリスタ。 ２ 酸化亜鉛粉末とチタン酸鉛粉末とを混合した
のち造粒し酸化亜鉛＋チタン酸鉛粒子を得る工程
と、該粒子を平均粒径により選別する工程と、該
工程で選別した粒子を少なくとも酸化亜鉛と酸化
ビスマスを含む主組成に添加混合して混合粒子を
得る工程と、該工程ののち混合粒子を成形焼結す
る工程とを具備したことを特徴とするバリスタの
製造方法。 ３ 造粒をスプレードライヤで行うことを特徴と
する特許請求の範囲第２項記載のバリスタの製造
方法。 ４ 酸化亜鉛に添加するチタン酸鉛の混合量が
0.01〜1.0モル％であることを特徴とする特許請
求の範囲第２項または第３項記載のバリスタの製
造方法。 ５ 酸化亜鉛＋チタン酸鉛粒子の平均粒径が10〜
200μｍであることを特徴とする特許請求の範囲
第２項〜第４項のいずれかに記載のバリスタの製
造方法。 ６ 主組成に添加混合する酸化亜鉛＋チタン酸鉛
粒子の添加量が0.3〜30重量％であることを特徴
とする特許請求の範囲第２項〜第５項のいずれか
に記載のバリスタの製造方法。[Scope of Claims] 1. A varistor consisting of a sintered body made of zinc oxide as a main component and mixed with several kinds of metal oxides including at least bismuth oxide and lead titanate, molded and sintered, wherein the titanate The amount of lead added
A varistor characterized in that the content is 0.00003 to 0.3 mol% in terms of PbTiO 3 form. 2 A step of mixing zinc oxide powder and lead titanate powder and then granulating them to obtain zinc oxide + lead titanate particles, a step of sorting the particles according to their average particle size, and a step of at least oxidizing the particles sorted in this step. A method for manufacturing a varistor, comprising the steps of: obtaining mixed particles by adding and mixing zinc and bismuth oxide to a main composition; and, after the step, forming and sintering the mixed particles. 3. The method for manufacturing a varistor according to claim 2, wherein the granulation is performed using a spray dryer. 4 The amount of lead titanate added to zinc oxide is
The method for producing a varistor according to claim 2 or 3, wherein the content is 0.01 to 1.0 mol%. 5 Average particle size of zinc oxide + lead titanate particles is 10~
The method for manufacturing a varistor according to any one of claims 2 to 4, wherein the thickness is 200 μm. 6. Production of a varistor according to any one of claims 2 to 5, characterized in that the amount of zinc oxide + lead titanate particles added to the main composition is 0.3 to 30% by weight. Method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58002520A JPS59205706A (en) | 1983-01-10 | 1983-01-10 | Varistor and method of producing same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58002520A JPS59205706A (en) | 1983-01-10 | 1983-01-10 | Varistor and method of producing same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59205706A JPS59205706A (en) | 1984-11-21 |
| JPH0142601B2 true JPH0142601B2 (en) | 1989-09-13 |
Family
ID=11531645
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58002520A Granted JPS59205706A (en) | 1983-01-10 | 1983-01-10 | Varistor and method of producing same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59205706A (en) |
-
1983
- 1983-01-10 JP JP58002520A patent/JPS59205706A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59205706A (en) | 1984-11-21 |
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