JPH07201530A - Method for manufacturing ceramic electronic component - Google Patents
Method for manufacturing ceramic electronic componentInfo
- Publication number
- JPH07201530A JPH07201530A JP5336379A JP33637993A JPH07201530A JP H07201530 A JPH07201530 A JP H07201530A JP 5336379 A JP5336379 A JP 5336379A JP 33637993 A JP33637993 A JP 33637993A JP H07201530 A JPH07201530 A JP H07201530A
- Authority
- JP
- Japan
- Prior art keywords
- varistor
- molded body
- ceramic
- molded
- firing
- 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
Links
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- Apparatuses And Processes For Manufacturing Resistors (AREA)
- Thermistors And Varistors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はセラミック電子部品の製
造方法に係り、具体的にはセラミック成形体の焼成方法
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ceramic electronic component, and more particularly to a method for firing a ceramic compact.
【０００２】[0002]
【従来の技術】例えば、電圧非直線抵抗体としてセラミ
ック原料から作られる酸化亜鉛バリスタは、ＺｎＯ（酸
化亜鉛）を主成分として、Ｂｉ2Ｏ3（酸化ビスマス）、
Ｓｂ2Ｏ3（酸化アンチモン）、Ａｌ2Ｏ3（酸化アルミニ
ウム）等の酸化物原料を混合した後に、有機バインダー
を添加して造粒し、続いてこれを板状のペレット（バリ
スタ成形体）に成形して焼成することにより製造され
る。2. Description of the Related Art For example, a zinc oxide varistor made of a ceramic material as a voltage non-linear resistor has ZnO (zinc oxide) as a main component and Bi 2 O 3 (bismuth oxide),
After mixing oxide raw materials such as Sb 2 O 3 (antimony oxide) and Al 2 O 3 (aluminum oxide), an organic binder is added and granulated, and subsequently, this is a plate-shaped pellet (varistor molded body). It is manufactured by molding and firing.
【０００３】以下に従来のセラミック電子部品の１つで
あるバリスタ素子の成形工程以降の製造方法について説
明する。A method of manufacturing a varistor element, which is one of conventional ceramic electronic components, after the molding step will be described below.
【０００４】図７は、従来の円板状のバリスタ成形体の
直径が１０mm以下の場合の成形工程以降の工程フローを
示すものである。まず、成形工程において円板状のバリ
スタ成形体を所定の厚みになるようにプレス成形し、次
に前述した成形体をランダムに焼成サヤにサヤ詰めする
サヤ詰め工程を経て、次の焼成工程で１２００〜１３０
０℃の温度で焼成してバリスタ焼結体を得、次の酸エッ
チング・面取り工程で焼結体の表面層状態を調整した
後、前記焼結体の両面に金属電極を形成する電極形成工
程とでバリスタ素子を製造している。FIG. 7 shows a process flow after the molding process when the diameter of the conventional disk-shaped varistor molded body is 10 mm or less. First, in a molding process, a disk-shaped varistor molded body is press-molded to have a predetermined thickness, and then the above-mentioned molded body is randomly packed in a firing sheath through a sheath filling step, and then in the next firing step. 1200-130
An electrode forming step of forming a varistor sintered body by firing at a temperature of 0 ° C., adjusting the surface layer state of the sintered body in the next acid etching / chamfering step, and then forming metal electrodes on both surfaces of the sintered body. And are producing varistor elements.
【０００５】図８は、従来の円板型のバリスタ成形体の
直径が１０mm以下の場合の焼成サヤ内のサヤ詰め状態を
示すものである。図８において、１はランダムに詰めら
れた多数個のバリスタ成形体であり、２はこれを収容す
る焼成サヤである。そしてこれを焼成する。FIG. 8 shows a packed state in the firing sheath when the diameter of the conventional disc type varistor molded body is 10 mm or less. In FIG. 8, 1 is a large number of varistor compacts that are randomly packed, and 2 is a firing sheath that accommodates them. And this is baked.
【０００６】しかしながら、図８に示す焼成方法では、
バリスタ成形体１の特に側面部が焼成サヤ２との接触部
分及びその近傍あるいは他のバリスタ成形体１との接触
部分とその近傍において、焼結体の焼結過程での粒成長
モードや組成が変化して、バリスタ特性が大きくばらつ
くことが判明した。However, in the firing method shown in FIG.
The grain growth mode and composition in the sintering process of the sintered body are different in the portion where the side surface of the varistor compact 1 is in contact with the firing sheath 2 and its vicinity, or the contact portion with other varistor compact 1 and its vicinity. It was found that the varistor characteristics varied greatly due to changes.
【０００７】そこで従来では、一定のバリスタ特性を得
るため、粒径や組成が変化したバリスタ焼結体の表面層
を、酸によるエッチング処理を施すことで除去する方法
がとられていた。Therefore, conventionally, in order to obtain a certain varistor characteristic, a method of removing the surface layer of the varistor sintered body having a changed grain size and composition by etching with an acid has been used.
【０００８】[0008]
【発明が解決しようとする課題】しかしながら、上述し
た従来の製造方法では、焼結体の表面層を除去する酸エ
ッチング・面取り工程で、焼結体の表面層を十分に均一
な状態にすることが難しくまた、設備コストや工数が余
計にかかるという問題点を有していた。However, in the above-mentioned conventional manufacturing method, the surface layer of the sintered body is made sufficiently uniform in the acid etching / chamfering step of removing the surface layer of the sintered body. In addition, there is a problem that equipment cost and man-hours are extra.
【０００９】本発明は上述した従来の問題点を解決する
もので、特性の変動をカバーした状態でセラミック成形
体を焼成し、特性バラツキの少ない焼結体を得ることが
でき、さらには、焼結体の表面処理工程の設備コストと
工数を低減できるセラミック電子部品の製造方法を提供
することを目的とする。The present invention solves the above-mentioned conventional problems, and it is possible to obtain a sintered body having a small variation in characteristics by firing a ceramic molded body in a state of covering fluctuations in the characteristics. An object of the present invention is to provide a method for manufacturing a ceramic electronic component, which can reduce the equipment cost and the number of steps in the surface treatment step of a unit.
【００１０】[0010]
【課題を解決するための手段】この目的を達成するため
の本発明によるセラミック電子部品の製造方法は、円板
型あるいは角板型の板状の側面部に同材料で一体となる
成形体側面突起部を有するセラミック成形体を得る成形
工程と、前記成形体をランダムに焼成用サヤ内にサヤ詰
めするサヤ詰め工程と、前記セラミック成形体を焼成し
てセラミック焼結体を得る焼成工程と、前記セラミック
焼結体の突起部を取り除く工程と、前記の工程で処理さ
れたセラミック焼結体の両面に金属電極を形成する工程
からなるものである。In order to achieve this object, a method of manufacturing a ceramic electronic component according to the present invention is directed to a side surface of a molded body which is made of the same material and is integrated with a plate-shaped side surface portion of a disc type or a square plate type. A molding step of obtaining a ceramic molded body having a protrusion, a sheath filling step of randomly packing the molded body in a firing sheath, and a firing step of firing the ceramic molded body to obtain a ceramic sintered body, It comprises a step of removing the protrusions of the ceramic sintered body and a step of forming metal electrodes on both surfaces of the ceramic sintered body treated in the above step.
【００１１】[0011]
【作用】本発明によれば、セラミック成形体を焼成させ
る場合にこの成形体が接触する部分は、成形体の面部と
焼結後の特性に大きく影響を及ぼす側面部に限定され
る。そしてこの場合、焼成時にセラミック成形体の側面
部が接触するのは、予め形成した突起部に限られ、焼成
時の側面部の不均一な粒成長や組成変化は、この突起部
のみに発生することとなる。そしてこの突起部は、次の
工程で簡単な面取り処理を施すことで除去されること
で、焼結体の均一な側面状態が得られることとなり、特
性バラツキの少ない焼結体を得ることができる。According to the present invention, when the ceramic molded body is fired, the contact portion of the molded body is limited to the surface portion of the molded body and the side surface portion that greatly affects the characteristics after sintering. In this case, the side surface portion of the ceramic molded body contacts during firing is limited to the pre-formed projection portion, and uneven grain growth and composition change of the side surface portion during firing occur only in this projection portion. It will be. Then, this protrusion is removed by performing a simple chamfering treatment in the next step, so that a uniform side surface state of the sintered body can be obtained, and a sintered body with less characteristic variation can be obtained. .
【００１２】[0012]
【実施例】以下本発明の一実施例に係るセラミック電子
部品の製造方法について、図面を参照しながら説明す
る。図１は本発明の実施例におけるセラミック電子部品
としてバリスタ素子を例とした製造工程フローを示すも
のである。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a ceramic electronic component according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a manufacturing process flow in which a varistor element is taken as an example of a ceramic electronic component in an embodiment of the present invention.
【００１３】まず、主原料であるＺｎＯ（酸化亜鉛）
と、Ｂｉ2Ｏ3（酸化ビスマス）、Ｓｂ 2Ｏ3（酸化アンチ
モン）、Ａｌ2Ｏ3（酸化アルミニウム）等の酸化物成分
から構成される原料粉抹をボールミル等で十分に粉砕、
混合した後、これに有機バインダーを添加して、スプレ
ードライヤーによる造粒を実施し、酸化亜鉛バリスタ用
の造粒粉を作製する。次に、造粒された原料をプレス成
形して、バリスタ成形体を作製する。First, the main raw material ZnO (zinc oxide)
And Bi2O3(Bismuth oxide), Sb 2O3(Anti-oxidation
Mon), Al2O3Oxide component such as (aluminum oxide)
Sufficiently crush the raw material powder consisting of
After mixing, add organic binder to it and spray
-Perform granulation with a dryer, for zinc oxide varistor
The granulated powder of is prepared. Next, press the granulated raw material
Shape to make a varistor compact.
【００１４】図２は、このバリスタ成形体を成形する金
型のモデルの断面図である。図２において３は成形金
型、４は成形される造粒粉を示す。そしてこの成形金型
３を使用して作製されたバリスタ成形体は、図３、図４
に示すように成形体本体５と、成形体側面突起部６とで
形成され、本実施例では、成形体本体５の直径が８mm、
成形体突起部６の高さが０．５mm、そして成形体本体５
の肉厚が１．２５mmとなるように円板型の成形体を作製
した。FIG. 2 is a sectional view of a model of a mold for molding this varistor molded body. In FIG. 2, 3 is a molding die, and 4 is a granulated powder to be molded. The varistor molded body produced by using this molding die 3 is shown in FIGS.
As shown in FIG. 4, the molded body 5 and the molded body side surface projections 6 are formed. In this embodiment, the molded body 5 has a diameter of 8 mm,
The height of the molded body projection 6 is 0.5 mm, and the molded body 5
A disk-shaped molded body was produced so that the thickness of the product was 1.25 mm.
【００１５】次に、上記のように製作された複数のバリ
スタ成形体７を、従来例と同様に図５に示すようにし
て、焼成サヤ８にランダムにサヤ詰めする。このとき、
各々のバリスタ成形体７は、図５に示すように、面部７
ａ及び成形体側面突起部６が焼成サヤ８及び他のバリス
タ成形体７と接触するが、成形体本体５の側面部には成
形体側面突起部６があるため、このような接触はない。Next, the plurality of varistor molded bodies 7 manufactured as described above are randomly packed in the firing sheath 8 as shown in FIG. 5 similarly to the conventional example. At this time,
Each varistor molded body 7 has a surface portion 7 as shown in FIG.
Although a and the molded body side surface protruding portion 6 come into contact with the firing sheath 8 and the other varistor molded body 7, such contact does not occur because the molded body side surface protruding portion 6 has the molded body side surface protruding portion 6.
【００１６】次にこのようにサヤ詰めされたバリスタ成
形体７を約１２５０℃の温度で６０〜１２０分間焼成し
て、バリスタ焼結体を得る。続いて、このバリスタ焼結
体に簡単な面取り処理を施すことで、焼結体側面の突起
部を除去した後、この焼結体の両面にＡｇ（銀）ペース
トを焼付けて電極を形成し、所望の特性を有するバリス
タ素子を得た。Next, the varistor molded body 7 thus packed in a sheath is fired at a temperature of about 1250 ° C. for 60 to 120 minutes to obtain a varistor sintered body. Subsequently, the varistor sintered body is subjected to a simple chamfering treatment to remove the protrusions on the side surfaces of the sintered body, and then an Ag (silver) paste is baked on both surfaces of this sintered body to form electrodes, A varistor element having desired characteristics was obtained.
【００１７】本実施例により得られたバリスタ素子の特
性と、従来の方法により製作されたバリスタ素子の特性
を（表１）に比較して示している。The characteristics of the varistor element obtained in this embodiment and the characteristics of the varistor element manufactured by the conventional method are shown in comparison with each other (Table 1).
【００１８】[0018]
【表１】 [Table 1]
【００１９】この（表１）から明らかなように、本実施
例で製作されたバリスタ素子のバリスタ電圧のバラツキ
を示した変動係数は、従来のものと比べ向上しており、
その他のバリスタ特性も良好に得られることが確認され
た。As is clear from (Table 1), the coefficient of variation showing the variation in the varistor voltage of the varistor element manufactured in this example is improved as compared with the conventional one.
It was confirmed that other varistor characteristics were also obtained satisfactorily.
【００２０】以上のように本実施例によれば、バリスタ
成形体７をランダムに焼成サヤ８に詰めて焼成を実施し
た場合に、このバリスタ成形体７が焼成サヤ８の内部で
不規則に焼成サヤ８の内壁や他のバリスタ成形体７と接
触することによって発生する焼結過程での粒成長モード
の変化や、Ｂｉ2Ｏ3，Ｓｂ2Ｏ3等の飛散成分の含有率が
変化して、バリスタ電圧やサージ電流耐量等のバリスタ
特性が部分的に低下する欠点を、バリスタ成形体７の側
面部に設けた成形体側面突起部６に集中させ、次工程の
簡単な面取り処理で、これを除去することで、効果的に
バリスタ特性の安定化を図ることができる。As described above, according to this embodiment, when the varistor molded body 7 is randomly packed in the firing sheath 8 and fired, the varistor molded body 7 is irregularly fired inside the firing sheath 8. Changes in the grain growth mode in the sintering process caused by contact with the inner wall of the sheath 8 and other varistor compacts 7 and changes in the content of scattered components such as Bi 2 O 3 , Sb 2 O 3 , The defect that the varistor characteristics such as the varistor voltage and the surge current resistance are partially deteriorated is concentrated on the molded body side surface protruding portion 6 provided on the side surface portion of the varistor molded body 7, and the By removing the, it is possible to effectively stabilize the varistor characteristics.
【００２１】尚、上記実施例は種々の変更が可能であ
る。実施例において、バリスタ成形体７の成形体側面突
起部６の形状は、種々の変更が可能であり、例えば、図
６（ａ），（ｂ）に示すように成形体側面突起部６の形
を断面三角形状やＴ字状に変形させても良い。また、本
発明は組成中に飛散し易い金属酸化物成分を含み、焼結
過程において粒成長を制御することが要求されるバリス
タ素子の製造に有効であるが、他の同様のセラミック電
子部品の製造に適用しても効果がある。また、成形体の
突起部の幅は、成形体本体の肉厚部の厚みによって、コ
ントロールされることは言うまでもない。The above embodiment can be modified in various ways. In the embodiment, the shape of the molded body side surface protruding portion 6 of the varistor molded body 7 can be variously changed. For example, as shown in FIGS. 6A and 6B, the shape of the molded body side surface protruding portion 6 can be changed. May be modified to have a triangular cross section or a T shape. Further, the present invention is effective in the production of a varistor element which contains a metal oxide component which easily scatters in the composition and which is required to control the grain growth in the sintering process. It is also effective when applied to manufacturing. Needless to say, the width of the protrusion of the molded body is controlled by the thickness of the thick portion of the molded body.
【００２２】さらに、焼成サヤ８に上記実施例ではラン
ダムに詰める例を示したが、縦詰めあるいは横詰めとし
て整列してサヤ詰めしてもよいことは言うまでもない。Further, in the above-mentioned embodiment, an example in which the firing sheath 8 is packed at random is shown, but it goes without saying that it may be arranged as vertically packed or horizontally packed and packed in the sheath.
【００２３】[0023]
【発明の効果】以上のように本発明は、円板型あるいは
角板型の板状の側面部に突起部を有したセラミック成形
体を作製し、これをランダムにサヤ詰めされた状態で焼
成し、次にこれによって得られた焼結体の突起部を除去
することで、特性バラツキの少ない焼結体を得ることが
でき、尚且つ、焼成後の焼結体の表面処理工程での設備
コストと工数を低減できるセラミック電子部品の製造方
法を提供できるものである。INDUSTRIAL APPLICABILITY As described above, according to the present invention, a disk-shaped or rectangular-plate-shaped plate-shaped ceramic molded body having protrusions on its side surface is manufactured, and the ceramic molded body is fired in a randomly packed sheath. Then, by removing the protrusions of the sintered body obtained by this, it is possible to obtain a sintered body with less variation in characteristics, and the equipment for the surface treatment step of the sintered body after firing. It is possible to provide a method for manufacturing a ceramic electronic component that can reduce costs and man-hours.
【図１】本発明の一実施例におけるセラミック電子部品
の製造方法を示した工程図FIG. 1 is a process diagram showing a method for manufacturing a ceramic electronic component according to an embodiment of the present invention.
【図２】同実施例における成形体の成形金型を示す断面
図FIG. 2 is a cross-sectional view showing a molding die of a molded body in the example.
【図３】同成形工程により得た成形体の底面図FIG. 3 is a bottom view of a molded body obtained by the molding process.
【図４】同成形体の断面図FIG. 4 is a sectional view of the molded body.
【図５】同成形体の焼成サヤへのサヤ詰めを示す要部の
断面図FIG. 5 is a cross-sectional view of the main part showing the filling of the molded body into the firing sheath.
【図６】（ａ）同成形体の他の例を示す要部の断面図 （ｂ）同じく成形体のさらに他の例を示す要部の断面図FIG. 6 (a) is a sectional view of a main part showing another example of the molded body, and (b) is a sectional view of a main part showing still another example of the molded body.
【図７】従来例のセラミック電子部品の製造方法を示す
要部の工程図FIG. 7 is a process diagram of a main part showing a method for manufacturing a ceramic electronic component of a conventional example.
【図８】同従来の成形体のサヤ詰めを示す要部の断面図FIG. 8 is a cross-sectional view of a main part showing a conventional filling of a molded body with a sheath.
【符号の説明】 ３ 成形金型 ４ 造粒粉 ５ 成形体本体 ６ 成形体側面突起部 ７ バリスタ成形体 ８ 焼成サヤ[Explanation of symbols] 3 molding die 4 granulated powder 5 molded body main body 6 molded body side projection 7 varistor molded body 8 firing sheath
Claims (2)
同材料で一体型となる成形体側面突起部を有するセラミ
ック成形体を得る成形工程と、前記成形体をランダムに
焼成用サヤ内にサヤ詰めするサヤ詰め工程と、前記セラ
ミック成形体を焼成してセラミック焼結体を得る焼成工
程と、前記セラミック焼結体の突起部を取り除く工程
と、前記の工程で処理されたセラミック焼結体の両面に
金属電極を形成する工程とからなるセラミック電子部品
の製造方法。1. A molding step for obtaining a ceramic molded body having a disk-shaped or rectangular plate-shaped plate-shaped side surface portion and a molded body side surface protruding portion that is an integral type of the same material, and for randomly firing the molded body. Saya filling step of filling the inside of the sheath, firing step of firing the ceramic molded body to obtain a ceramic sintered body, step of removing the protruding portion of the ceramic sintered body, and ceramic processed in the above step A method of manufacturing a ceramic electronic component, comprising the steps of forming metal electrodes on both surfaces of a sintered body.
詰めに整列してサヤ詰めした請求項第１記載のセラミッ
ク電子部品の製造方法。2. The method for producing a ceramic electronic component according to claim 1, wherein the ceramic molded bodies are vertically packed or horizontally packed and sheathed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5336379A JP3057989B2 (en) | 1993-12-28 | 1993-12-28 | Manufacturing method of ceramic electronic components |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5336379A JP3057989B2 (en) | 1993-12-28 | 1993-12-28 | Manufacturing method of ceramic electronic components |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07201530A true JPH07201530A (en) | 1995-08-04 |
| JP3057989B2 JP3057989B2 (en) | 2000-07-04 |
Family
ID=18298535
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5336379A Expired - Fee Related JP3057989B2 (en) | 1993-12-28 | 1993-12-28 | Manufacturing method of ceramic electronic components |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3057989B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011132081A (en) * | 2009-12-25 | 2011-07-07 | Nichicon Corp | Method for producing positive temperature coefficient thermistor, and sintered compact of positive temperature coefficient thermistor |
-
1993
- 1993-12-28 JP JP5336379A patent/JP3057989B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011132081A (en) * | 2009-12-25 | 2011-07-07 | Nichicon Corp | Method for producing positive temperature coefficient thermistor, and sintered compact of positive temperature coefficient thermistor |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3057989B2 (en) | 2000-07-04 |
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