JPH0383875A - Production of porous ceramic structure - Google Patents
Production of porous ceramic structureInfo
- Publication number
- JPH0383875A JPH0383875A JP21911989A JP21911989A JPH0383875A JP H0383875 A JPH0383875 A JP H0383875A JP 21911989 A JP21911989 A JP 21911989A JP 21911989 A JP21911989 A JP 21911989A JP H0383875 A JPH0383875 A JP H0383875A
- Authority
- JP
- Japan
- Prior art keywords
- slurry
- ceramic
- porous
- foam
- ceramic slurry
- 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
- 239000000919 ceramic Substances 0.000 title claims abstract description 42
- 238000004519 manufacturing process Methods 0.000 title claims description 11
- 239000002002 slurry Substances 0.000 claims abstract description 34
- 239000006260 foam Substances 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims description 23
- 238000001035 drying Methods 0.000 claims description 9
- 238000010304 firing Methods 0.000 claims description 6
- 238000005470 impregnation Methods 0.000 claims description 4
- 239000011148 porous material Substances 0.000 abstract description 8
- 239000000463 material Substances 0.000 abstract description 2
- 238000001354 calcination Methods 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 7
- 210000004027 cell Anatomy 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 229920005830 Polyurethane Foam Polymers 0.000 description 2
- 238000005119 centrifugation Methods 0.000 description 2
- 239000012700 ceramic precursor Substances 0.000 description 2
- 230000008034 disappearance Effects 0.000 description 2
- 239000011496 polyurethane foam Substances 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 210000000497 foam cell Anatomy 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
Landscapes
- Filtering Materials (AREA)
- Compositions Of Oxide Ceramics (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、目詰まり（孔閉塞）のない微細通気孔が均質
に分布した高強度の多孔質セラ壽ソクス構造体の製造方
法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a high-strength porous ceramics structure in which fine air pores without clogging (pore clogging) are uniformly distributed.
［従来の技術］
多孔質のセラミックス構造体は、耐熱性、化学的安定性
などに優れているため、溶融金属用フィルター、通気性
断熱材、触媒担体、パーティキュレート捕集材といった
多様な用途分野で実用されている。[Prior art] Porous ceramic structures have excellent heat resistance and chemical stability, so they can be used in a variety of fields such as molten metal filters, breathable insulation materials, catalyst supports, and particulate collection materials. It is put into practical use.
この多孔Ｉセラミックス構造体については従来から多種
の製造技術が提案されているが、工程的に最も簡便な手
段は、三次元網目構造を備える有機質多孔体の骨格面に
セラミックススラリーを付着させたのち、乾燥、焼成す
る方法である。しかし、前記の方法を実施する場合には
、セラミックススラリーの付着条件によって組織に目詰
まりを生じたり、強度特性の不足を招いたりすることが
多い、したがって、製造面の課題として、組織に目詰ま
りのない均質な微細通気孔を形成すること、高い骨格強
度を付与できること、工程回数を減少し低コストで製品
化できること、等が挙げられている。Various manufacturing techniques have been proposed for this porous I-ceramic structure, but the simplest method in terms of process is to attach a ceramic slurry to the skeletal surface of an organic porous body with a three-dimensional network structure. , drying and firing. However, when implementing the above method, clogging of the structure or lack of strength properties often occurs depending on the adhesion conditions of the ceramic slurry. It is possible to form homogeneous microscopic vents without any pores, to be able to impart high skeletal strength, to reduce the number of steps and to be able to commercialize the product at low cost.
このうち、目詰まりを抑制するための手段としては、１
回の操作により付着するセラミックススラリーの量を少
なくして、付着から乾燥までの工程を反復する方法が提
案されている（特開昭５９−３０５９号公報）、ところ
が、この方法を用いて十分な骨格強度を得るためには少
なくとも４回の操作を繰返す必要があり、工程が長期化
する問題点がある。Among these, as a means to suppress clogging, 1.
A method has been proposed in which the amount of ceramic slurry deposited is reduced in each operation and the process from deposition to drying is repeated (Japanese Patent Application Laid-open No. 59-3059). In order to obtain skeletal strength, it is necessary to repeat the operation at least four times, which poses the problem of prolonging the process.
１回の操作だけで目的とする多孔質セラミックスを製造
する手段としては、特定された比率で圧縮した有機質多
孔体にセラミックススラリーを充填したのち、圧縮体を
当初の体積に復元させて乾燥、焼成する方法が特開昭６
３−１５６０８４号公報に開示されている。しかし、１
回充填で付着量を多くすると孔閉塞を起すうえに、この
方法では有機質成分が分解消失した後の孔にセラミック
ス成分が充填されないため、組織強度が高まらない難点
がある。As a means of manufacturing the desired porous ceramics in just one operation, after filling a ceramic slurry into an organic porous body compressed at a specified ratio, the compressed body is restored to its original volume, dried, and fired. The method to do this is JP-A-6
It is disclosed in Japanese Patent No. 3-156084. However, 1
If the amount of adhesion is increased by repeated filling, it will cause pore clogging, and in this method, the pores are not filled with ceramic components after the organic components have decomposed and disappeared, so there is a problem that the tissue strength cannot be increased.
このように、従来技術では、上述した製造面の課題要求
を全面的に満足する方法は未だに開発されていない。As described above, in the prior art, a method that completely satisfies the above-mentioned manufacturing issues has not yet been developed.
本発明の目的は、目詰まりのない均質な微細通気孔を分
布しながら優れた骨格強度を備える高性能の多孔質セラ
ミックス構造体を少ない工程により製造する方法を提供
するところにある。An object of the present invention is to provide a method for manufacturing a high-performance porous ceramic structure having excellent skeletal strength while uniformly distributing fine air pores without clogging, using a small number of steps.
上記の目的を達成するための本発明による多孔質セラミ
ックス構造体の製造方法は、有機質多孔発泡体にセラく
ツクススラリ−を含浸し、余剰スラリーを除去したのち
、乾燥、仮焼成する第１工程、仮焼成体にセラミックス
スラリーを再含浸し、余剰スラリーを除去したのち、乾
燥、焼成する第２工程からなることを構成上の特徴とす
るものである。A method for manufacturing a porous ceramic structure according to the present invention to achieve the above object includes a first step of impregnating an organic porous foam with a ceramic slurry, removing excess slurry, drying and pre-firing; The structure is characterized by a second step of re-impregnating the pre-fired body with ceramic slurry, removing excess slurry, and then drying and firing.
本発明に供する有機質多孔発泡体としては、例えばポリ
ウレタンフォームのような４００〜５００″Ｃで分解揮
散する性質の樹脂発泡体が使用される。As the organic porous foam used in the present invention, for example, a resin foam such as polyurethane foam that decomposes and volatilizes at 400 to 500''C is used.
セラミックススラリーには、３１０！、Ａｌｔｏｓなど
の酸化物系、ＳｉＣ、８４Ｃのような炭化物系、ＢＮ。310 for ceramic slurry! , oxide type such as Altos, carbide type such as SiC, 84C, BN.
Ｓｉ３Ｎ４などの窒化物系等、各種のセラ逅ツクス微粉
末を水あるいは有機溶媒に分散懸濁させたものが適用さ
れる。この際、必要に応じ常用の界面活性剤、分散剤な
どを併用する。スラリーの粘度は１０〜１００ポイズの
範囲に設定することが好適で、１０ポイズ未満の粘度で
はセラミックス含有量が低過ぎ、また１００ポイズを越
えると含浸が円滑に進まなくなる。Various ceramic fine powders such as nitrides such as Si3N4 are dispersed and suspended in water or an organic solvent. At this time, commonly used surfactants, dispersants, etc. are used in combination, if necessary. The viscosity of the slurry is preferably set in the range of 10 to 100 poise; if the viscosity is less than 10 poise, the ceramic content will be too low, and if it exceeds 100 poise, impregnation will not proceed smoothly.
有機質多孔発泡体にセラミックススラリーを含浸するに
は、セラミックススラリー中に有機質多孔発泡体を浸漬
する方法が用いられ、含浸後の成形棒は遠心分離、通風
など適宜な手段によって余剰スラリーを除去したのち、
乾燥する。ついで、４００〜ｓｏｏ ’ｃの温度で仮焼
成して有機質多孔発泡体をＩ或する有機成分を分解揮散
させて除去する。To impregnate an organic porous foam with a ceramic slurry, a method is used in which the porous organic foam is immersed in a ceramic slurry, and after the impregnated molded rod is centrifuged or ventilated, excess slurry is removed by appropriate means. ,
dry. Then, the organic porous foam is calcined at a temperature of 400 to 400°C to decompose and volatilize certain organic components and remove them.
上記の第１工程で、有機質多孔発泡体のセル構造に沿っ
た微細通気孔と有機成分の消失跡が空洞化した脆弱な多
孔混在組織の未焼結セラミックス体が形成される。In the first step described above, an unsintered ceramic body having a fragile porous mixed structure in which fine air holes along the cell structure of the organic porous foam and traces of organic component disappearance are hollowed out is formed.
本発明の第２工程は、第１工程で得られた未焼結多孔セ
ラくツクス体にセラミックススラリーを再含浸し、同様
にして余剰スラリーを除去したのち、乾燥、焼成するプ
ロセスからなる。The second step of the present invention consists of re-impregnating the unsintered porous ceramic body obtained in the first step with ceramic slurry, removing excess slurry in the same manner, and then drying and firing.
再含浸にあたっては、セラミックススラリーが通気孔を
閉塞することなしに有機質多孔発泡体の消失跡に円滑か
つ十分に浸透する条件を選定することが重要で、このた
めにはセラミックススラリーの粘度を２〜２０ポイズの
範囲まで低下させ、浸漬処理を低圧下の環境でおこなう
ことが効果的である。When re-impregnating, it is important to select conditions that will allow the ceramic slurry to smoothly and sufficiently penetrate into the areas where the organic porous foam has disappeared without clogging the ventilation holes. It is effective to lower the pressure to a range of 20 poise and perform the immersion treatment in a low pressure environment.
最終的な焼成は、セラミックス成分が焼結する１０００
°Ｃ以上の温度域でおこなって、本発明の多孔質セラミ
ックス構造体を得る。The final firing is 1000 ml, where the ceramic components are sintered.
The porous ceramic structure of the present invention is obtained by carrying out the process in a temperature range of .degree. C. or higher.
本発明のプロセスによれば、第１工程の段階で有機質多
孔発泡体のセル構造に沿った微細通気孔と有機成分の消
失跡が空洞化した混在多孔組織のセラミックス前駆体が
形成される。この多孔セラミックス前駆体は前記空洞部
分を含む極めて脆弱な組織体であり、かつ発泡体セル構
造の空隙を形成している三角形の各頂点がとがっている
ため、セル構造が頂点付近で破壊されやすい。According to the process of the present invention, in the first step, a ceramic precursor having a mixed porous structure in which fine air holes along the cell structure of the organic porous foam and traces of organic component disappearance are hollowed out is formed. This porous ceramic precursor is an extremely fragile structure including the hollow portion, and each vertex of the triangle forming the void of the foam cell structure is sharp, so the cell structure is easily destroyed near the vertex. .
このような理由から、１回の含浸、加熱、焼結処理を施
したのみでは強度的に不充分な個所がでてくる。したが
って、均一な強度を有する多孔質構造体を得るために、
セル構造の内部から補強を施すことが必要となってくる
。For these reasons, there will be areas where the strength is insufficient even if the impregnation, heating, and sintering treatments are performed only once. Therefore, in order to obtain a porous structure with uniform strength,
It becomes necessary to provide reinforcement from within the cell structure.
第２工程はこの要請を満すためにおこなわれるプロセス
で、この工程の付加により空洞部分の微細気孔に目詰り
を生じることなく、セル構造の強度が均一な多孔質組織
の形成が可能になる。The second step is a process carried out to meet this requirement, and the addition of this step makes it possible to form a porous structure with uniform cell structure strength without clogging the micropores in the cavity. .
以下、本発明の実施例を比較例と対比して説明する。 Examples of the present invention will be described below in comparison with comparative examples.
実施例
（１）第１工程
平均粒子径５０μ−以下のＳｔＣ＠粉末を水に分散懸濁
させて、粘度８０ポイズのスラリーを作成した。このセ
ラミックススラリーに軟質ポリウレタンフォーム〔ブリ
ジストン側製、エバーライトスコツト＃４〕を浸漬して
引上げ、余剰のスラリーを遠心分離により除去したのち
、８０°Ｃの温度で乾燥した。Example (1) First Step StC@ powder having an average particle diameter of 50 μm or less was dispersed and suspended in water to create a slurry with a viscosity of 80 poise. A flexible polyurethane foam (manufactured by Bridgestone, Everlite Scotto #4) was immersed in this ceramic slurry, pulled up, excess slurry was removed by centrifugation, and then dried at a temperature of 80°C.
乾燥後の成形棒を、大気中、４００ ’Ｃの温度で仮焼
成してポリウレタン成分を分解揮散させて消去した。The dried molded rod was calcined in the air at a temperature of 400'C to decompose and volatilize the polyurethane component.
（２）第２工程
第１工程の同一のＳｉＣ＠粉末を水に分散懸濁させて粘
度１５ポイズのスラリーを作製した。このスラリーをオ
ートクレーブに移して第１工程で仮焼成した成形棒を再
び浸漬し、系内を真空引きしながら２０分間含浸処理し
た。余剰のスラリーを遠心分離により除去し、８０°Ｃ
で乾燥した。(2) Second step The same SiC@ powder as in the first step was dispersed and suspended in water to prepare a slurry with a viscosity of 15 poise. This slurry was transferred to an autoclave, and the molded rod pre-baked in the first step was immersed again, and impregnated for 20 minutes while the inside of the system was evacuated. Remove excess slurry by centrifugation and heat at 80°C.
It was dried.
乾燥後の成形棒を２１００°Ｃの温度で焼成し、ＳｔＣ
成分を完全に焼結して強固な骨格を形成した。After drying, the formed rod is fired at a temperature of 2100°C and StC
The components were completely sintered to form a strong skeleton.
比較例１
ＳｔＣをセラミックス成分とする粘度５００ポイズのス
ラリーを用い、実施例の第１工程と同様な操作で含浸し
た。乾燥後、２１００°Ｃの温度で焼成処理を施して、
実施例と同レベルの嵩比重をもつ多孔質セラミックス構
造体を作成した。Comparative Example 1 Using a slurry containing StC as a ceramic component and having a viscosity of 500 poise, impregnation was carried out in the same manner as in the first step of the example. After drying, it is fired at a temperature of 2100°C,
A porous ceramic structure having the same bulk specific gravity as the example was created.
比較例２
ＳｉＣをセラミックス成分とする粘度５０ポイズのスラ
リーを用いて実施例の浸漬から乾燥までの操作を６回繰
返し、最終的に２１００°Ｃの温度で焼成して多孔質セ
ラミックス構造体を形成した。Comparative Example 2 Using a slurry with a viscosity of 50 poise containing SiC as a ceramic component, the operations from dipping to drying in the example were repeated six times, and finally fired at a temperature of 2100°C to form a porous ceramic structure. did.
上記の実施例、比較例１および２で作成した多孔質セラ
ミックス戒形体の各種特性と工程所要時間を対比して下
表に示した。The table below shows a comparison of various characteristics and process times of the porous ceramic shaped bodies produced in the above Examples and Comparative Examples 1 and 2.
（表注）（ＩＨｃ−当たりの目詰まり数。(Table note) (Number of clogs per IHc.
（２）実施例を１とした場合の指数。(2) Index when Example is set as 1.
上表の結果から、比較例１は目詰まりが多く発生すると
共に骨格強度が極端に低く、比較例２は優れた特性性状
を示したが工程時間が実施例の３倍必要であった。実施
例は特性性状および工程所要時間を含めた相対評価で、
比較例２より優っていることが認められる。From the results shown in the above table, Comparative Example 1 caused a lot of clogging and had extremely low skeleton strength, while Comparative Example 2 showed excellent properties, but required three times the process time as the Example. Examples are relative evaluations including characteristics and process time,
It is recognized that it is superior to Comparative Example 2.
以上のとおり、本発明に従えば第１工程および第２工程
からなる簡易な２段階プロセスにより、均質な微細通気
孔が分布する骨格強度の高い多孔質セラミックス構造体
を得ることができる。したがって、耐熱・耐食性が要求
される各種フィルター、担体、断熱材などを比較的安価
に量産することが可能となる。As described above, according to the present invention, a porous ceramic structure with high skeletal strength in which fine pores are uniformly distributed can be obtained by a simple two-step process consisting of a first step and a second step. Therefore, it becomes possible to mass-produce various filters, carriers, heat insulating materials, etc. that require heat resistance and corrosion resistance at relatively low cost.
Claims (1)
、余剰スラリーを除去したのち、乾燥、仮焼成する第１
工程、仮焼成体にセラミックススラリーを再含浸し、余
剰スラリーを除去したのち、乾燥、焼成する第２工程か
らなることを特徴とする多孔質セラミックス構造体の製
造方法。 ２、第１工程で含浸するセラミックススラリーの粘度を
１０〜１００ポイズとし、第２工程で再含浸するセラミ
ックススラリーの粘度を２〜２０ポイズに設定する請求
項１記載の多孔質セラミックス構造体の製造方法。 ３、第２工程の再含浸を低圧下でおこなう請求項１記載
の多孔質セラミックス構造体の製造方法。[Claims] 1. A first step in which an organic porous foam is impregnated with ceramic slurry, excess slurry is removed, and then dried and pre-fired.
1. A method for producing a porous ceramic structure, comprising a second step of re-impregnating the pre-fired body with ceramic slurry, removing excess slurry, drying and firing. 2. Manufacturing the porous ceramic structure according to claim 1, wherein the viscosity of the ceramic slurry impregnated in the first step is set to 10 to 100 poise, and the viscosity of the ceramic slurry impregnated again in the second step is set to 2 to 20 poise. Method. 3. The method for manufacturing a porous ceramic structure according to claim 1, wherein the re-impregnation in the second step is performed under low pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21911989A JP2603139B2 (en) | 1989-08-24 | 1989-08-24 | Method for manufacturing porous ceramic structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21911989A JP2603139B2 (en) | 1989-08-24 | 1989-08-24 | Method for manufacturing porous ceramic structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0383875A true JPH0383875A (en) | 1991-04-09 |
| JP2603139B2 JP2603139B2 (en) | 1997-04-23 |
Family
ID=16730544
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21911989A Expired - Lifetime JP2603139B2 (en) | 1989-08-24 | 1989-08-24 | Method for manufacturing porous ceramic structure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2603139B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0580593A (en) * | 1991-09-18 | 1993-04-02 | Iwatsu Electric Co Ltd | Engraving machine |
| KR20030086149A (en) * | 2002-05-03 | 2003-11-07 | 최덕환 | Packing box |
| CN112295312A (en) * | 2019-07-25 | 2021-02-02 | 江苏正迈过滤技术有限公司 | Production method of medical filter element |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2766389B1 (en) * | 1997-07-25 | 1999-09-03 | Pechiney Recherche | SILICON CARBIDE FOAM WITH HIGH SPECIFIC SURFACE AND IMPROVED MECHANICAL CHARACTERISTICS |
| TW424154B (en) | 1998-10-30 | 2001-03-01 | Teijin Ltd | Phase film and optical device using same |
-
1989
- 1989-08-24 JP JP21911989A patent/JP2603139B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0580593A (en) * | 1991-09-18 | 1993-04-02 | Iwatsu Electric Co Ltd | Engraving machine |
| KR20030086149A (en) * | 2002-05-03 | 2003-11-07 | 최덕환 | Packing box |
| CN112295312A (en) * | 2019-07-25 | 2021-02-02 | 江苏正迈过滤技术有限公司 | Production method of medical filter element |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2603139B2 (en) | 1997-04-23 |
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