JPH05262569A - Firing of formed ceramic material containing oxide having high vapor pressure - Google Patents
Firing of formed ceramic material containing oxide having high vapor pressureInfo
- Publication number
- JPH05262569A JPH05262569A JP4060140A JP6014092A JPH05262569A JP H05262569 A JPH05262569 A JP H05262569A JP 4060140 A JP4060140 A JP 4060140A JP 6014092 A JP6014092 A JP 6014092A JP H05262569 A JPH05262569 A JP H05262569A
- Authority
- JP
- Japan
- Prior art keywords
- firing
- vapor pressure
- high vapor
- sheet
- molded body
- 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.)
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- Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
- Ceramic Capacitors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は高蒸気圧酸化物を含むセ
ラミック成形体の焼成方法に係り、特に、チップ型積層
セラミックコンデンサ等の製造にあたり、高蒸気圧酸化
物を含む製品用のセラミック成形体を耐火物製容器内に
装入して焼成する際、焼成雰囲気を好適に制御して含有
される高蒸気圧酸化物の揮散による焼成損失を防止する
ことにより、所望組成の製品を確実に得ることを可能と
する方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for firing a ceramic formed body containing a high vapor pressure oxide, and more particularly to a ceramic formed for a product containing a high vapor pressure oxide in manufacturing a chip type multilayer ceramic capacitor or the like. When the body is charged into a refractory container and fired, the firing atmosphere is appropriately controlled to prevent firing loss due to volatilization of the high vapor pressure oxide contained, thereby ensuring a product of the desired composition. It relates to a method that makes it possible to obtain.
【０００２】[0002]
【従来の技術】積層セラミックコンデンサを製造するに
は、例えば、誘電体グリーンシートに内部電極を印刷し
た後、所定のサイズに打抜いてこの打抜きシートを積み
重ね、圧着後、各チップのサイズに合わせて切断する。
次いで、切断済みの生チップをセラミック製焼成台の上
に載せ、１０００〜１４００℃の温度で焼成する。焼成
後のチップは、両端部に内部電極接続用端子電極を設
け、更に、はんだ耐熱性向上のために電気めっきが施さ
れる。2. Description of the Related Art To manufacture a monolithic ceramic capacitor, for example, an internal electrode is printed on a dielectric green sheet, punched to a predetermined size, the punched sheets are stacked, pressure-bonded, and then adjusted to the size of each chip. And disconnect.
Next, the cut raw chips are placed on a ceramic baking table and baked at a temperature of 1000 to 1400 ° C. The baked chip is provided with internal electrode connection terminal electrodes at both ends, and is further electroplated to improve solder heat resistance.
【０００３】従来、上記生チップの焼成にあたり、該生
チップが揮発性の高蒸気圧酸化物を含むものである場合
には、焼成時の焼成雰囲気を均一に保つために、生チッ
プを載置した焼成台は、これを多段に重ねて、セラミッ
ク製の匣鉢内に装入し、密閉した状態で焼成が行なわれ
ている。Conventionally, when firing the above-mentioned raw chips, when the raw chips contain a volatile high vapor pressure oxide, the raw chips are placed on the firing to keep the firing atmosphere uniform during firing. The table is stacked in multiple stages, placed in a ceramic bowl, and fired in a sealed state.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、セラミ
ック製匣鉢内で密閉した状態で焼成を行なった場合にお
いても、高蒸気圧酸化物の揮散を確実に防止することは
できず、このため、 高蒸気圧酸化物の揮散により、目的とする組成の焼成
品が得られない。However, even when firing is performed in a ceramic container in a sealed state, it is not possible to reliably prevent the vaporization of high vapor pressure oxides, and therefore, Due to the vaporization of vapor pressure oxide, a fired product having the intended composition cannot be obtained.
【０００５】匣鉢内の位置、即ち、多段に積み重ねた
焼成台の上下位置、により焼成にムラがあり、得られる
焼成品の組成が異なる。[0005] Firing varies depending on the position inside the bowl, that is, the vertical position of the firing tables stacked in multiple stages, and the composition of the obtained fired product differs.
【０００６】などの不具合があり、目的とする電気特性
のものを得ることが難しく、しかも製品特性のバラツキ
が大きいという欠点があった。However, there are drawbacks such that it is difficult to obtain desired electrical characteristics and the product characteristics vary greatly.
【０００７】本発明は上記従来の問題点を解決し、高蒸
気圧酸化物を含む製品用のセラミック成形体を耐火物製
容器内に装入し、該容器を密閉した状態にて加熱して焼
成する方法において、高蒸気圧酸化物の揮散を防止し
て、目的組成の焼成品を容易かつ効率的に得ることがで
きる高蒸気圧酸化物を含むセラミック成形体の焼成方法
を提供することを目的とする。The present invention solves the above-mentioned conventional problems, and a ceramic molded product for a product containing a high vapor pressure oxide is placed in a refractory container, and the container is heated in a sealed state. In a firing method, it is possible to provide a method for firing a ceramic molded body containing a high vapor pressure oxide, which can prevent the vaporization of a high vapor pressure oxide and easily and efficiently obtain a fired product having a target composition. To aim.
【０００８】[0008]
【課題を解決するための手段】請求項１の高蒸気圧酸化
物を含むセラミック成形体の焼成方法は、高蒸気圧酸化
物を含む製品用のセラミック成形体を耐火物製容器内に
装入し、該容器を密閉した状態にて加熱して焼成する方
法において、該容器内に該高蒸気圧酸化物又は該高蒸気
圧酸化物を含む材料よりなる雰囲気制御用成形体を入れ
ておいて焼成を行なうことを特徴とする。According to a first aspect of the present invention, there is provided a method for firing a ceramic molded body containing a high vapor pressure oxide, wherein a ceramic molded body for a product containing a high vapor pressure oxide is charged into a refractory container. Then, in the method of heating and firing the container in a sealed state, an atmosphere control molded body made of the high vapor pressure oxide or a material containing the high vapor pressure oxide is placed in the container. It is characterized by performing firing.
【０００９】請求項２の高蒸気圧酸化物を含むセラミッ
ク成形体の焼成方法は、請求項１の方法において、前記
雰囲気制御用成形体は、シート状成形体であって、該容
器内に敷かれており、該シート状の雰囲気制御用成形体
の上に高融点酸化物のシートが置かれ、該シートの上に
前記製品用のセラミック成形体が載置されて焼成が行な
われることを特徴とする。According to a second aspect of the present invention, there is provided a method for firing a ceramic molded body containing a high vapor pressure oxide according to the first aspect, wherein the atmosphere controlling molded body is a sheet-shaped molded body. A high-melting-point oxide sheet is placed on the sheet-shaped atmosphere control molded article, and the ceramic molded article for the product is placed on the sheet and fired. And
【００１０】以下に図面を参照して、本発明の高蒸気圧
酸化物を含むセラミック成形体の焼成方法を詳細に説明
する。A method for firing a ceramic compact containing a high vapor pressure oxide of the present invention will be described in detail below with reference to the drawings.
【００１１】図１は本発明の高蒸気圧酸化物を含むセラ
ミック成形体の焼成方法の一実施方法を示す、一部を切
り欠いた斜視図である。FIG. 1 is a partially cutaway perspective view showing one embodiment of a method for firing a ceramic molded body containing a high vapor pressure oxide of the present invention.
【００１２】本実施例の方法では、雰囲気制御用成形体
１としてシート状の成形体を用い、このシート状の雰囲
気制御用成形体を、焼成台２の台板２Ａ上に敷き、更
に、この雰囲気制御用成形体１の上に高融点酸化物のシ
ート３を置き、このシート３の上に製品用のセラミック
成形体（本実施例では生チップ）４を多数整列して載置
している。In the method of this embodiment, a sheet-shaped molded body is used as the atmosphere-controlled molded body 1, and this sheet-shaped molded body for atmosphere control is laid on the base plate 2A of the firing table 2 and further A high-melting-point oxide sheet 3 is placed on the atmosphere control molded body 1, and a large number of product ceramic molded bodies (raw chips in this embodiment) 4 are arranged on the sheet 3. ..
【００１３】焼成に際しては、セラミック成形体４を載
置した焼成台２を、図示しない台板を介してコンベア上
に載置された焼成匣鉢に詰め、上蓋をして密閉状態とし
た後、コンベアにより焼成炉に搬送して、例えば１〜２
時間、大気圧下、１０００〜１４００℃の温度で焼成を
行なう。When firing, the firing table 2 on which the ceramic molded body 4 is placed is packed into a firing bowl placed on a conveyor via a base plate (not shown), and the lid is closed to make it hermetically sealed. It is conveyed to a firing furnace by a conveyor and, for example, 1-2
Baking is performed at a temperature of 1000 to 1400 ° C. for an hour and at atmospheric pressure.
【００１４】これにより、焼成中に雰囲気制御用成形体
１に含有される高蒸気圧酸化物が揮散し、焼成雰囲気が
当該高蒸気圧酸化物の高濃度雰囲気となるため、製品用
のセラミック成形体４からの高蒸気圧酸化物の揮散が有
効に防止される。As a result, the high vapor pressure oxide contained in the atmosphere control molded body 1 is volatilized during firing, and the firing atmosphere becomes a high concentration atmosphere of the high vapor pressure oxide, so that ceramic molding for products is performed. Volatilization of the high vapor pressure oxide from the body 4 is effectively prevented.
【００１５】また、セラミック成形体４は高融点酸化物
のシート３上に載置しており、焼成台２や雰囲気制御用
成形体１と接触しないため、これらとの反応が起こるこ
とはない。Further, since the ceramic molded body 4 is placed on the high melting point oxide sheet 3 and does not come into contact with the firing table 2 or the atmosphere controlling molded body 1, a reaction with these does not occur.
【００１６】本発明において、雰囲気制御用成形体は、
焼成するセラミック成形体に含有される高蒸気圧酸化物
又は高蒸気圧酸化物を含む材料よりなるものであって、
通常の場合、焼成するセラミック成形体と同組成のセラ
ミックグリーンシートが用いられる。In the present invention, the atmosphere control molded body is
A material comprising a high vapor pressure oxide or a high vapor pressure oxide contained in a ceramic molded body to be fired,
Usually, a ceramic green sheet having the same composition as the ceramic molded body to be fired is used.
【００１７】一方、高融点酸化物のシートとしては、焼
成するセラミック成形体と焼成台又は雰囲気制御用成形
体との反応を防止し得る熱的、化学的に安定なものであ
れば良く、通常の場合、Ａｌ2 Ｏ3 、ＺｒＯ、ＭｇＯ等
の１種又は２種以上を主成分とするセラミックグリーン
シートが用いられる。On the other hand, the sheet of high-melting-point oxide may be any sheet that is thermally and chemically stable so as to prevent the reaction between the ceramic molded body to be fired and the firing table or the atmosphere control molded body. In this case, a ceramic green sheet containing one or more of Al 2 O 3 , ZrO, MgO and the like as a main component is used.
【００１８】これら雰囲気制御用成形体のシートの厚さ
や高融点酸化物のシートの厚さには特に制限はなく、取
り扱い性等の面から十分な強度を確保し得る程度であれ
ば良い。通常の場合、雰囲気制御用成形体のシートと高
融点酸化物のシートとは、これをラミネートして一体化
して使用される。There is no particular limitation on the thickness of the atmosphere control molded body sheet or the high melting point oxide sheet, as long as sufficient strength can be secured from the viewpoint of handleability and the like. Usually, the atmosphere control molded body sheet and the high melting point oxide sheet are used by laminating and integrating them.
【００１９】なお、図示の例は本発明の一実施例であっ
て、本発明はその要旨を超えない限り、何ら図示の方法
に限定されるものではない。The illustrated example is an embodiment of the present invention, and the present invention is not limited to the illustrated method as long as the gist thereof is not exceeded.
【００２０】例えば、雰囲気制御用成形体の形状はシー
ト状に限られず、厚さの厚い板状であっても良い。ま
た、任意の塊状のものを、製品用のセラミック成形体と
共に焼成容器内に装入しても良い。更に、高融点酸化物
のシートも厚さの厚い板状であっても良く、また、雰囲
気制御用成形体や焼成台と製品用のセラミック成形体と
の反応が起こり難い場合であれば、高融点酸化物の板体
は用いなくても良い。For example, the shape of the atmosphere control molded body is not limited to the sheet shape, and may be a thick plate shape. Further, an arbitrary lump may be placed in the firing container together with the ceramic molded body for the product. Further, the high-melting-point oxide sheet may be in the form of a thick plate, and if the reaction between the atmosphere control molded body or the firing table and the ceramic molded body for the product is difficult to occur, The plate of melting point oxide may not be used.
【００２１】本発明において、焼成される高蒸気圧酸化
物を含む製品用のセラミック成形体としては、例えば、
鉛系、リチウム系等が挙げられる。In the present invention, examples of the ceramic molded body for the product containing the high vapor pressure oxide to be fired include:
Lead-based, lithium-based, etc. may be mentioned.
【００２２】[0022]
【作用】本発明の方法によれば、高蒸気圧酸化物を含む
雰囲気制御用成形体を、製品用のセラミック成形体と共
に密閉容器内に装入して焼成を行なうため、焼成雰囲気
は、この雰囲気制御用成形体から揮散する高蒸気圧酸化
物により、高蒸気圧酸化物を高濃度で含有する雰囲気と
なる。このため、製品用のセラミック成形体からの高蒸
気圧酸化物の揮散は防止され、目的組成及び目的特性を
有し、かつ、バラツキのない製品を得ることが可能とな
る。According to the method of the present invention, the atmosphere control molded body containing the high vapor pressure oxide is charged into the closed container together with the ceramic molded body for the product and fired. The high vapor pressure oxide volatilized from the atmosphere control molded body provides an atmosphere containing a high concentration of high vapor pressure oxide. Therefore, volatilization of the high vapor pressure oxide from the ceramic molded product is prevented, and it is possible to obtain a product having a target composition and properties and having no variation.
【００２３】請求項２の方法によれば、製品用セラミッ
ク成形体と雰囲気制御用成形体や焼成治具等との反応を
確実に防止して、より良好な製品を得ることが可能とな
る。According to the method of claim 2, it is possible to surely prevent the reaction between the product ceramic molded product and the atmosphere control molded product, the firing jig, etc., and to obtain a better product.
【００２４】[0024]
【実施例】以下に実施例及び比較例を挙げて、本発明を
より具体的に説明する。EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples.
【００２５】実施例１ 図１に示す方法により、鉛ペロブスカイト系のセラミッ
ク誘電体からなる生チップの焼成を行なった。即ち、Ａ
ｌ2 Ｏ3 を主成分とするグリーンシートと上記生チップ
と同組成の鉛ペロブスカイト系のセラミックグリーンシ
ートとをラミネートして得られた焼成用シート（縦８０
ｍｍ，横１００ｍｍ，厚さ２５０μｍ）を焼成台（縦９
０ｍｍ，横１０５ｍｍ，厚さ５ｍｍ，脚部の長さ９ｍ
ｍ）の台板上に敷き、生チップをこの焼成用シートの上
に約７００個載せた。Example 1 A raw chip made of a lead perovskite ceramic dielectric was fired by the method shown in FIG. That is, A
A firing sheet obtained by laminating a green sheet containing l 2 O 3 as a main component and a lead perovskite-based ceramic green sheet having the same composition as that of the green chip (vertical 80
mm, width 100 mm, thickness 250 μm)
0mm, width 105mm, thickness 5mm, leg length 9m
m) was laid on the base plate, and about 700 fresh chips were placed on the baking sheet.
【００２６】このようにして焼成用シートを介して生チ
ップを載せた焼成台を、複数個、一辺の長さが１４０ｍ
ｍの匣鉢内に積み重ね、焼成炉にて、大気圧下、１１０
０℃で２時間焼成した。In this way, a plurality of firing tables on which raw chips are placed via the firing sheet, each side having a length of 140 m
It is piled up in a m bowl and heated in a firing furnace at atmospheric pressure for 110
It was calcined at 0 ° C. for 2 hours.
【００２７】比較例１ 実施例１において、焼成用シートを用いなかったこと以
外は同様にして生チップの焼成を行なった。Comparative Example 1 Raw chips were baked in the same manner as in Example 1 except that the baking sheet was not used.
【００２８】考察 実施例１及び比較例１において、焼成により得られたチ
ップを各々１０００個採取し、顕微鏡でチップ表面の色
ムラ発生の有無を観察した。その結果、比較例１では、
焼成台内部と周辺部で焼成ムラが３〜４割程度発生した
のに対し、実施例１では、焼成ムラの発生がなかった。
なお、比較例１で得られた焼成ムラ発生チップの電気特
性を測定したところ、容量劣化が生じていた。このこと
から、本発明に係る焼成用シートが有効に機能してお
り、本発明の方法によれば、高特性の製品を歩留り良く
得ることができることが明らかである。 Discussion In each of Example 1 and Comparative Example 1, 1000 chips obtained by firing were sampled, and the presence or absence of color unevenness on the chip surface was observed with a microscope. As a result, in Comparative Example 1,
About 30 to 40% of the firing unevenness occurred inside and on the periphery of the firing table, but in Example 1, the firing unevenness did not occur.
In addition, when the electrical characteristics of the firing unevenness generation chip obtained in Comparative Example 1 were measured, capacity deterioration occurred. From this, it is clear that the baking sheet according to the present invention is effectively functioning, and that the method of the present invention makes it possible to obtain a product having high characteristics with high yield.
【００２９】[0029]
【発明の効果】以上詳述した通り、本発明の方法によれ
ば、高蒸気圧酸化物を含むセラミック成形体の焼成にあ
たり、焼成中の高蒸気圧酸化物の揮散による組成変化を
防止して、所期目的の組成及び所望の特性を有する製品
を、製品間のバラツキなく、高い歩留りにて容易かつ効
率的に得ることができる。請求項２の方法によれば、よ
り一層高特性な製品を確実に得ることができる。As described in detail above, according to the method of the present invention, when firing a ceramic molded body containing a high vapor pressure oxide, composition change due to volatilization of the high vapor pressure oxide during firing is prevented. A product having a desired composition and desired properties can be easily and efficiently obtained with a high yield without variations among products. According to the method of claim 2, it is possible to surely obtain a product having higher characteristics.
【００３０】[0030]
【図１】本発明の高蒸気圧酸化物を含むセラミック成形
体の焼成方法の一実施方法を示す一部切り欠き斜視図で
ある。FIG. 1 is a partially cutaway perspective view showing a method of firing a ceramic molded body containing a high vapor pressure oxide of the present invention.
１ 雰囲気制御用成形体 ２ 焼成台 ３ 高融点酸化物の板体 ４ セラミック成形体 1 atmosphere control molded body 2 firing table 3 high melting point oxide plate body 4 ceramic molded body
Claims (2)
ク成形体を耐火物製容器内に装入し、該容器を密閉した
状態にて加熱して焼成する方法において、 該容器内に該高蒸気圧酸化物又は該高蒸気圧酸化物を含
む材料よりなる雰囲気制御用成形体を入れておいて焼成
を行なうことを特徴とする高蒸気圧酸化物を含むセラミ
ック成形体の焼成方法。1. A method of charging a ceramic molded body for a product containing a high vapor pressure oxide into a refractory container and heating and firing the container in a sealed state, wherein A method for firing a ceramic formed body containing a high vapor pressure oxide, characterized in that an atmosphere control formed body made of a high vapor pressure oxide or a material containing the high vapor pressure oxide is placed and fired.
セラミック成形体の焼成方法において、前記雰囲気制御
用成形体は、シート状成形体であって、該容器内に敷か
れており、該シート状の雰囲気制御用成形体の上に高融
点酸化物のシートが置かれ、該シートの上に前記製品用
のセラミック成形体が載置されて焼成が行なわれること
を特徴とする高蒸気圧酸化物を含むセラミック成形体の
焼成方法。2. The method for firing a ceramic molded body containing a high vapor pressure oxide according to claim 1, wherein the atmosphere control molded body is a sheet-shaped molded body and is laid in the container. A high-melting-point oxide sheet is placed on the sheet-shaped atmosphere control molded article, and the ceramic molded article for the product is placed on the sheet and fired. A method for firing a ceramic compact containing a vapor pressure oxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4060140A JP3000781B2 (en) | 1992-03-17 | 1992-03-17 | Method of firing ceramic compact containing high vapor pressure oxide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4060140A JP3000781B2 (en) | 1992-03-17 | 1992-03-17 | Method of firing ceramic compact containing high vapor pressure oxide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05262569A true JPH05262569A (en) | 1993-10-12 |
| JP3000781B2 JP3000781B2 (en) | 2000-01-17 |
Family
ID=13133540
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4060140A Expired - Lifetime JP3000781B2 (en) | 1992-03-17 | 1992-03-17 | Method of firing ceramic compact containing high vapor pressure oxide |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3000781B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006273643A (en) * | 2005-03-29 | 2006-10-12 | Kyocera Corp | Sintered compact, wiring board and method for producing the same |
| JP2011037673A (en) * | 2009-08-12 | 2011-02-24 | Murata Mfg Co Ltd | Dielectric ceramic, method for manufacturing the same, and multilayer ceramic capacitor |
-
1992
- 1992-03-17 JP JP4060140A patent/JP3000781B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006273643A (en) * | 2005-03-29 | 2006-10-12 | Kyocera Corp | Sintered compact, wiring board and method for producing the same |
| JP2011037673A (en) * | 2009-08-12 | 2011-02-24 | Murata Mfg Co Ltd | Dielectric ceramic, method for manufacturing the same, and multilayer ceramic capacitor |
| US8390985B2 (en) | 2009-08-12 | 2013-03-05 | Murata Manufacturing Co., Ltd. | Dielectric ceramic and method for producing dielectric ceramic and laminated ceramic capacitor |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3000781B2 (en) | 2000-01-17 |
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