JP2000264755A - Production of ceramic porous body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reducing a ceramic porous body the form of pores of which can be controlled by utilizing a form for supporting pores, which has never been found. SOLUTION: The ceramic porous body is produced by allowing a ceramic slurry containing air bubbles and a ceramic powder to gel to form a gel-like porous formed body and, after demolding, successively subjecting the gel-like porous formed body to drying, degreasing and firing. Or, the ceramic porous body is produced by mechanically introducing air bubbles into a ceramic slurry containing a ceramic powder to prepare a ceramic slurry containing air bubbles, then allowing the resultant ceramic slurry to gel to form a gel-like porous formed body and, after demolding, successively subjecting the gel-like porous formed body to drying, degreasing and firing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for producing a porous ceramic body having pores, and more particularly, to a technique for producing a porous ceramic body capable of controlling the form of pore distribution.

[0002]

2. Description of the Related Art Conventionally, various methods for producing a ceramic porous body have been known, and they can be roughly classified into the following four methods. The first method is a method in which a ceramic powder (on the order of μm) is incompletely fired to form a porous ceramic body having pores of the size of the powder. In this method, the firing is set at a low temperature and in a short time in a firing process for producing a dense body. According to this method, the pore diameter can be controlled by the powder size of the raw material, and the distribution or inclination of the pore diameter can be provided by using raw materials having different particle diameters. However, this method has the drawback that the pore size is about μm even if it is large, and that the strength is low due to incomplete sintering.

A second method is a method of mixing an organic substance with a ceramic raw material or a ceramic slurry and removing the organic substance in a degreasing and firing process. In this method, the porosity can be controlled by the amount of the organic substance contained, and the pore diameter can be controlled to some extent by the size of the organic substance, but it is difficult to control the pore diameter distribution. The third method is a method in which bubbles are contained in a ceramic slurry by a foaming agent, or bubbles are contained by reacting a metal such as slag or magnesium to generate a gas such as hydrogen or carbon dioxide. is there. In this method, a method has been proposed in which pores are aggregated to form inclined pores, and several tens of μm to 1000 μm are formed.
A degree of pore size gradient has been reported. The fourth method is a method in which a three-dimensional network structure is formed of an organic material (generally a urethane resin), and a ceramic slurry is impregnated with the organic material and fired to obtain a porous body.

[0004]

However, in these methods, the controllability of the form of pores, the formability, the strength of the obtained ceramic, and the like are not always sufficient. Therefore, the present invention utilizes an unconventional bubble holding form,
It is an object of the present invention to provide a method for manufacturing a porous ceramic body capable of controlling the pore morphology. Another object of the present invention is to provide a method for producing a porous ceramic body having a controlled pore distribution form.

[0005]

Means for Solving the Problems As means for solving the above problems, the present inventors have completed the following invention. That is, the present invention provides a method for forming a gel-like porous molded body by gelling a ceramic slurry containing ceramic powder having bubbles and drying, degreasing, and firing the demolded gel-like porous molded body. Provided is a method for producing a porous body. The present invention also provides a bubble-containing ceramic slurry by mechanically introducing bubbles into a ceramic slurry containing ceramic powder, and gelling the bubble-containing ceramic slurry to form a gel-like porous molded body. And
Drying, degreasing, and firing the demolded gel-like porous molded body,
Provided is a method for manufacturing a porous ceramic body. Further, in these methods, a method for producing a ceramic porous body, wherein the bubble-containing slurry contains a gelling agent. Also,
Provided is a method for producing a ceramic porous body, wherein the bubble-containing slurry contains a polymerizable monomer and a polymerization initiator. Further, in these methods, the present invention provides a method for producing a porous ceramic body, in which, in the step of forming the gel-like porous molded body, bubbles in the bubble-containing ceramic slurry are oriented by gravity and / or centrifugal force. The present invention also provides a method for producing a porous ceramic body, wherein the porous gel body is a porous gel body having inclined pores. Further, the present invention provides an average pore size of 0.1 μm or more and 100 μm
The present invention provides a porous body having pores smaller than m and pores having an average pore diameter of 100 μm or more and 3000 μm or less inside.

According to the method of the present invention, the bubbles in the cell-containing ceramic slurry are retained in the gel by gelation, and a gel-like porous molded body is obtained. By demolding, drying, degreasing, and sintering the gel-like porous compact holding the air bubbles, a ceramic porous body in which pores are distributed while being held by the gel-like porous compact is obtained.

[0007]

Embodiments of the present invention will be described below in detail. The method for producing a porous ceramic body of the present invention is characterized in that a porous ceramic slurry is solidified to obtain a water-retentive porous molded body. (Preparation of Cell-Containing Ceramic Slurry) To prepare cell-containing ceramic slurry, first, it is preferable to prepare a slurry having no bubbles (hereinafter simply referred to as ceramic slurry). The ceramic slurry contains ceramic particles. The ceramic component of the ceramic powder for preparing the slurry is not particularly limited in type, and may be a known oxide-based or non-oxide-based ceramic or a combination of two or more types of viscous minerals. Can be used. Preferably, it is in the form of powder or powder. Examples of the oxide-based ceramics include alumina-based, mullite-based, and zirconia-based ceramics, and examples of the non-oxide-based ceramics include silicon carbide-based, silicon nitride-based, aluminum nitride-based, boron nitride-based, and graphite-based ceramics. Can be mentioned. An oxide ceramic is preferred, and an alumina is particularly preferred. The average particle size is not particularly limited, but is preferably 0.1 μm or more and less than 10 μm.
This is because when a ceramic having an average particle diameter in this range is used, the strength of a sintered body obtained by sintering can easily be 25 Mpa or more. The average particle size is more preferably
It is 0.1 μm or more and 5 μm or less. More preferably,
0.1 μm or more and 1 μm or less, most preferably,
It is 0.1 μm or more and 0.6 μm or less.

In the ceramic slurry, the medium in which the ceramic particles are suspended is not particularly limited, and water, an organic solvent, a mixed solvent thereof or the like can be used.
It is preferable to use an appropriate dispersing agent in order to uniformly include the ceramic powder in the ceramic slurry. As the dispersant, conventionally known various dispersants can be selected and used in consideration of the ceramic component and other components. Typically, an ammonium polycarboxylate dispersant (anionic dispersant) can be used.

The ceramic slurry further contains a gelling material capable of gelling the slurry to form a porous body holding water or a solvent in a molding step of injecting the slurry into a mold. I have. Examples of such a material for gelation include a usual gelling agent and a polymerizable material comprising a monomer and a polymerization initiator. If a gelling agent is used, the slurry will be gelled by temperature control, pH control, or the like. Examples of the gelling agent include gelatin, agarose, agar, sodium alginate and the like.

When a polymerizable material is used, the slurry is gelled by polymerization of the monomer (mainly radical polymerization). Examples of the monomer of the polymerizable material include a monomer having one functional group or two or more functional groups. Specific examples include monomers having one or more vinyl groups, allyl groups, and the like. When the slurry is composed of water or an aqueous solvent, it is preferable to use a mono- or bifunctional polymerizable monomer. Also,
When the slurry is composed of an organic solvent, the slurry is preferably a bifunctional polymerizable monomer. In particular, when the slurry is prepared using water as a solvent, preferably, at least one monofunctional acrylamide and at least one bifunctional acrylamide are used in combination. When the slurry is prepared with an organic solvent, preferably, at least two kinds of bifunctional acrylic acid are used in combination.

When a polymerizable material is used, the rate of polymerization varies depending on the type and amount of the polymerization initiator. The polymerization initiator is usually inactive at room temperature in many cases, but it is not always necessary to use the polymerization initiator simultaneously with the monomer material to prepare a ceramic slurry. If necessary, it is added separately from the monomer. As the polymerization initiator, conventionally known various polymerization agents can be used. Which polymerization initiator is used is selected depending on the type of the monomer and how the gelation is performed. 1
When a functional group monomer or a bifunctional group monomer is used, it is preferably ammonium persulfate or potassium persulfide. When a functional monomer having two or more functional groups is used, preferably, an organic peroxide, a hydrogen peroxide compound, or an azo or diazo compound is used. Specifically, it is benzoyl peroxide.

It is preferable to add such a gelling material to the ceramic slurry before introducing the bubbles. This is because if the gelling material is further added after the bubbles are once introduced into the slurry, the bubbles may disappear or decrease.

Various additives such as a known lubricant and a surfactant can be added to the ceramic slurry.
Surfactants facilitate the introduction of air bubbles. Examples of the surfactant include alkylbenzenesulfonic acid and higher alkyl amino acids. Specifically, dodecylbenzene sulfonic acid, polyoxyethylene sorbitan monolaurate, polyoxyethylene monooleate, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, and the like. Further, a thickener, a sizing agent and the like can be added. Examples of the thickener and the sizing agent include methylcellulose, polyvinyl alcohol, saccharose, molasses, xanthan gum and the like. Thickeners, sizing agents, and the like are suitable for stably holding the introduced bubbles.
Further, a ceramic fiber material or metal or ceramic chip material for imparting properties such as strength to the obtained ceramic porous body can be added. Further, a trace amount of an inorganic compound which promotes sintering of the porous ceramic body can be added.

When bubbles are introduced by adding a foaming agent, the foaming agent is added. As the foaming agent, a protein-based foaming agent, a surfactant-based foaming agent, or the like can be used.

(Introduction of air bubbles into ceramic slurry,
Preparation of Bubble-Containing Ceramic Slurry) Various methods can be adopted for introducing bubbles into the ceramic slurry to obtain a bubble-containing ceramic slurry. When bubbles are generated by a chemical reaction or the like, foaming conditions of a predetermined foaming agent (foaming agent) can be given. Also, a gas can be introduced into the slurry from the outside by stirring the slurry, blowing gas into the slurry, or the like. The method of introducing bubbles from the outside is preferable in terms of simplicity and the fact that impurities are not contained in the slurry. The introduced gas is preferably retained in the slurry as bubbles by a surfactant or the like. The amount of bubbles introduced and the diameter of bubbles introduced in the bubble introduction step can be adjusted by the type and amount of the surfactant, or the temperature and concentration of the slurry.

When a polymerizable material is used as the gelling material in the bubble introducing step, it is preferable to add a polymerization initiator or a polymerization initiator and a polymerization catalyst.
This is because it is convenient to transfer the slurry to the solidification step once the introduced bubbles are held in the slurry as it is. If a polymerization catalyst is added, the time of the gelation step can be adjusted by the gelation temperature and the amount added. Usually, when a polymerization catalyst is added, gelation (polymerization) is started immediately at around room temperature. Therefore, the use and type of the polymerization catalyst are selected in consideration of the bubble introduction method, the bubble introduction amount, and the like. As the polymerization catalyst, for example, N, N,
N ', N'-tetramethylenediamine and the like can be mentioned.

(Molding step) The thus prepared bubble-containing ceramic slurry is poured into a mold and gelled to form a gel-like porous molded body. Various molding methods can be used as the molding method. It is also applicable to extrusion molding. The gelation in this step means that the resin is self-cured substantially without desolvation.
In other words, solidification molding is performed in a state where water or an organic solvent used as a medium of the slurry is held. Therefore, a mold that does not allow solvent or water to permeate is used as the mold. When a gelling agent is used, gelation is performed by temperature control and / or pH control (adjusted during or before the bubble introduction step). Conditions for gelation (temperature, pH, etc.)
Depends on the type of gelling agent, gel concentration, ionic strength in slurry, ceramic content, and the like. The temperature and pH are set in consideration of these parameters, and the gel time is also set.

In the case of gelation using a polymerizable material, the type of monomer, the type of polymerization initiator, the type of solvent,
Further, the temperature for polymerization is set in consideration of the presence or absence of a polymerization catalyst. In the case of aqueous slurry, usually 20 ° C
Or more, preferably 25 ° C. or more and 80 ° C. or less. More preferably, it is 25 ° C. or more and 35 ° C. or less. In the case of an organic solvent-based slurry, the temperature is usually 100 ° C or higher, preferably 100 ° C or higher and 120 ° C or lower. The time for gelling is also set in consideration of various parameters as in the case of the temperature. In the case of an aqueous slurry, usually 1
The time is 0 minutes or more, and preferably about 20 minutes or more and several hours or less. More preferably, it is 1 hour or more and 4 hours or less. In the case of an organic solvent-based slurry, it is usually at least 5 minutes, preferably about 5 to 30 minutes.

(Control of pore diameter, pore distribution, etc.) When the slurry is gelled, bubbles existing in the slurry are also stored in the gel. As a result, the gel-like body becomes porous, and a gel-like porous molded body is obtained. Until the gelation is completed, in the bubble-containing ceramic slurry, movement of bubbles, decomposition and aggregation of bubbles occur. By utilizing this, it is possible to control the bubble diameter and pore distribution in the gelation step. First, as described above, the pore diameter is controlled by the type and the amount of the surfactant used when introducing bubbles by, for example, mechanical energy at the time of introducing bubbles as described above. If the surfactant used is cationic, the pore size tends to decrease, and if the amount of the surfactant increases, the pore size tends to increase. Second, the slurry temperature and the gelation time in the gelling step are adjusted. As the slurry temperature increases, the pore size tends to increase, and as the gelation time increases, the pore size tends to increase.

The pore distribution can be controlled by the concentration of the slurry. That is, if the slurry concentration is relatively high,
For example, when it exceeds 80% by weight, a region where small-diameter pores are distributed tends to be formed in the upper layer portion. Preferably, it is at least 85% by weight. On the other hand, when the slurry concentration is relatively low, for example, 80% by weight or less,
There is a tendency that a region in which small diameter pores are distributed can be formed in the lower part. In this case, the content is preferably 60% by weight or more. That is, in the lower part, the pore diameter becomes smaller due to the decomposition and shrinkage of the bubbles due to the pressure of the slurry, and in the upper part, the pore diameter becomes larger due to the coalescence and expansion of the bubbles. In the lower part, the bubbles rise, so that the matrix part becomes large and dense, and in the upper part, the amount of pores becomes large. Such control of the pore diameter and pore distribution is caused by the action of gravity or the like when the bubble-containing ceramic slurry is poured into a molding die and allowed to stand. It is also possible.

In the molding step utilizing gelation, unlike the slip casting method, there is no orientation of the ceramic powder as a raw material, and the ceramic powder is uniformly dispersed and held, thereby obtaining a uniform matrix. Therefore, a uniform matrix can be obtained without the orientation of the raw material powder.
Further, in the method of the present invention, by controlling the gelling temperature and the gelling time, it is possible to control the formation of bubbles in a state where the raw material particles are uniformly held without being oriented. Further, since the gelation time and the gelation temperature can be easily controlled, the degree of freedom in controlling the bubbles is high. Further, since the solidification is performed while holding the medium component, a molded body having a smooth surface and reduced cracks and roughness can be obtained. In addition, because the matrix is supported by the gelling agent or the polymer, the molded body has higher strength than the conventional cast molded body,
It is convenient for handling in the process up to sintering, and hardly causes breakage. In addition, using the present gelation step means that there is no orientation, good moldability,
Since the strength of the gel-like molded body is high, it is convenient to obtain a large-sized or a porous body having a complicated shape.

After obtaining the gel-like porous molded body in a desired form in this way, it is removed from the mold, dried, degreased, and fired. In the method of the present invention, since a water-impermeable mold is used, the mold is easily released and, since it is a gel, the molded body is not easily damaged during the mold release. Drying is performed so that water and a solvent contained in the gel-like porous molded body are evaporated. The drying conditions (temperature, humidity, time, etc.) are appropriately adjusted depending on the type of the solvent used for preparing the slurry and the components (gelling agent or polymer) constituting the skeleton of the gel-like porous molded article. In particular, in the method of the present invention, in the drying step,
It is preferable that the pores do not move or decompose or aggregate due to drying. That is, it is preferable that the drying step is performed while holding the pores in the molded body. By drying in this manner, the orientation of the ceramic particles present in the matrix is preserved at the time of gelation. In the case of a molded article from an aqueous slurry, usually 20
° C or higher, preferably 25 ° C or higher and 80 ° C or lower, more preferably 25 ° C or higher and 40 ° C or lower. Also, it is usually one hour or more. Preferably, it is at least 8 hours, more preferably at least 24 hours. Also, in particular,
While controlling the humidity (relative humidity) so as to gradually decrease, the temperature is 20 ° C. or more and 30 ° C. or less, preferably about 25 ° C.
Then, it takes about 24 to 200 hours to dry,
More preferred. Relative humidity, 95% RH to 60% R.
It is preferred to reduce to H. In addition, it is preferable to decrease at 5% RH / day. Such drying, in particular,
Suitable for drying molded articles using water as a medium. For example, using water as a medium and methacrylamide as a monomer
In the case of a gel-like porous molded body prepared from a slurry using N, N'-methylenebisacrylamide, at 25 ° C., the humidity was reduced from 95% to 60% RH at a rate of 5% / day to about 1%.
Dried over a week. In the case of a molded body from an organic solvent-based slurry, the temperature is usually 40 ° C. or higher, preferably 110 ° C. or more.
° C or higher.

Next, in order to remove organic components from the dried product, heating is performed at a higher temperature. The temperature and time for degreasing are adjusted according to the amount and type of organic components used.
For example, methacrylamide as a material for gelation
In the case of a gel-like porous molded body prepared from a slurry using N, N-methylenebisacrylamide, it was degreased at 700 ° C. for 2 days.

After degreasing, a firing step is performed. Conditions for firing are set in consideration of the type of ceramic material used and the like. In particular, when a ceramic powder having an average particle diameter of submicron (0.1 μm to 0.6 μm) is used, the matrix can be densified by sintering at a high temperature.

Through such steps, the ceramic porous body of the present invention can be obtained. Since the ceramic porous body of the present invention has undergone the gel forming step, it has a uniform and non-oriented matrix and has pores. Since the pore diameter, porosity, and pore distribution can be adjusted by controlling the gelling step and the like, the porous body can have a uniform matrix while having a non-uniform pore diameter and pore distribution.

Since the gel-like porous molded article obtained by the method of the present invention is not oriented, the shrinkage during firing also occurs isotropically. As a result, the dimensional accuracy is improved, and there is no crack or the like. Also, the raw material in the molded body is uniform without orientation, that the molded body is easy to release,
Also, since the strength of the molded body is sufficient, the molded body is hardly damaged or distorted, and the sintered body is hardly defective. As a result, the manufacturing method is such that high strength can be obtained. Further, according to the present method, a sintered body having a smooth surface can be obtained. In addition, since a sintered body faithful to the shape of the molded body can be obtained, it is easy to obtain a large-sized or complicated shaped sintered body.

The obtained porous body has a porosity of 50
% Or more and 90% or less. Preferably, 60% or more and 80
% Or less. In addition, in the step of gelation from the slurry, when movement, decomposition, aggregation, etc. occur in the pores, a region where small pores are distributed (small diameter region) and a region where large pores are distributed (large diameter). Region) is formed. In particular, a small diameter region is easily formed on one surface layer side, and a large diameter region is easily formed on the inner side. The small diameter region is easily formed in a range from 1 μm to several μm from the surface of the ceramic porous body. In particular, a small-diameter region is easily formed in a range up to 1 μm. The small pores referred to herein are pores having a size of 0.1 μm or more and less than 100 μm, preferably 10 μm or more and 50 μm or less. Large pores having a diameter of several hundreds μm or more and several thousand μm or less are distributed inside the small diameter region. In such a large diameter region, the pore size gradually increases from the small diameter region, and the boundary with the small diameter region may be unclear. A diameter region may be formed in some cases. The pore diameter of the pores in the large diameter region is preferably 20
It is at least 0 μm, more preferably at least 300 μm.

In particular, in the present invention, a porous body having a clear boundary between the small diameter region and the large diameter region is easily obtained. In such a porous body, pores of 0.1 μm or more and less than 100 μm exist in a range of 1 μm from one surface, and on the inner side therefrom,
Pores of 100 μm or more and 3000 μm or less exist. Preferably, it is 200 μ or more, more preferably 30 μm or more.
There are pores of 0 μm or more. The porosity of such a porous body is 50% or more and 90% or less, and the porosity in a range of 1 μm from one surface is 20% or more and 70% or less.
It is as follows. Preferably, it is 40% or more and 60% or less. In this porous body, the fluid permeability differs between the small diameter region side and the large diameter region side, and a gas filter, a dust collection filter,
It is suitable for various filters such as filters for water treatment. In addition, the provision of the small-diameter region and the large-diameter region provides excellent heat resistance and conductivity, and is suitable for use at high temperatures. From the above, the porous body of the present invention having the small diameter region and the large diameter region is particularly suitable for a dust collection filter, a gas filter, and a water treatment filter used at a high temperature.

Further, in the small diameter region, the porosity is small, and the matrix portion is larger than the pore portion. For this reason, the porous body is denser than the large diameter region, and has a higher strength in the surface layer on the small diameter region side. For this reason, it is effective in preventing generation of cracks when severe stress is applied in high-temperature dust collection.

[0030]

According to the method for producing a porous ceramic body of the present invention, it is possible to provide a method for producing a porous body having good moldability and easy pore control. Further, according to the ceramic porous body of the present invention, it is possible to provide a ceramic porous body in which a small-diameter region exists on the surface layer side, a large-diameter region exists therein, and the small-diameter region is dense.

[0031]

The present invention will be specifically described below with reference to examples. In the present example, alumina powder (average particle size: 0.6 μm) was used as the ceramic powder. Distilled water 10
0 g of methacrylamide 2 which is a monofunctional monomer
0 g and 2 g of N, N'-methylenebisacrylamide as a bifunctional monomer were dissolved, and 2.7 g of Serna D305 (manufactured by Chukyo Oil & Fats Co., Ltd.) as an ammonium polycarboxylate dispersant was added. , Alumina powder 500
g was added and mixed in a wet ball mill for 48 hours in a thermostatic water bath.

The operation was carried out under a nitrogen atmosphere. At room temperature, 0.2 g of ammonium persulfate as a polymerization initiator, 0.3 g of N, N, N ', N'-tetramethyleneethylenediamine as a catalyst, and Newrex R (Nippon Oil & Fats Co., Ltd.) as a surfactant were added to this mixture at room temperature. Was added to obtain a ceramic slurry. In this slurry, methacrylamide was 3.2 wt%, N, N'-
Methylenebismethacrylamide 0.32 wt%, dispersant 0.54 wt%, polymerization initiator 0.03 wt%,
0.06 wt% of catalyst, 0.07 wt% of surfactant,
The slurry concentration was 50 v / v% (80 wt%).

A stirring rod having a stirring blade at the lower end was penetrated into the slurry in the container, and the stirring rod was rotated at 3000 rpm for 5 minutes. Due to this stirring, bubbles were contained in the slurry. Then, this slurry was poured into a cylindrical mold (made of Teflon, diameter 30 mm, height 60 mm) and gelled at 25 ° C. for 2 hours. During the gelation process, the bubbles were defoamed or decomposed and aggregated to form many small bubbles in the lower layer and large bubbles in the upper layer. Thereafter, the molded body was released from the molding die. The demolded molded article had a wet and smooth surface, and had sufficient strength and flexibility for easy handling.

The following was operated in a normal air atmosphere.
Then, the molded body is heated at 25 ° C. from 95% RH to 60%.
% RH was reduced by 5% RH per day and dried for 8 days. Then, after degreasing at 700 ° C for 2 days, 15
It was baked at 50 ° C. for 2 hours.

The pore distribution of the obtained porous body was observed from its fracture surface. As a result, a large number of pores having a pore diameter of 1 μm or more and less than 100 μm exist in a range of 1 μm from the surface, and 10 μm from the inside to the surface on the opposite side.
There were many pores of 0 μm or more and 3000 μm or less. The pores were spherical, mainly continuous pores.
When the porosity was measured from the product dimensions and mass,
7%. The obtained porous body had a smooth surface and no defects were observed. Further, it was a sintered body maintaining the form of the molded body. When the strength was measured by a three-point bending test, it was 27 Mpa.

Continued on the front page (72) Inventor Takehisa Fukui 1-172-6, Akinaricho, Obu-shi, Aichi Prefecture (72) Inventor Satoshi Ohara 1-10 Wakakusacho, Obu-shi, Aichi Prefecture Nagata Mansion A-204 (72) Inventor Abe Hiroya 1-288-1 Higashishinmachi, Obu City, Aichi Prefecture

Claims (7)

[Claims] 1. A foamed ceramic slurry containing bubbles and ceramic powder is gelled to form a gel-like porous molded body, and the demolded gel-like porous molded body is dried, degreased, and fired. A method for manufacturing a porous ceramic body. 2. A bubble-containing ceramic slurry is prepared by mechanically introducing bubbles into a ceramic slurry containing ceramic powder, and the bubble-containing ceramic slurry is gelled to form a gel-like porous molded body. And drying, degreasing, and firing the demolded gel-like porous molded body. 3. The foamed ceramic slurry contains:
3. The method for producing a porous ceramic body according to claim 1, further comprising a gelling agent. 4. The foamed ceramic slurry contains:
3. The method for producing a porous ceramic body according to claim 1, wherein the method comprises a polymerizable monomer and a polymerization initiator. 5. The method for producing a ceramic porous body according to claim 1, wherein, in the step of forming the gel-like porous molded body, the bubbles in the bubble-containing ceramic slurry are oriented by gravity and / or centrifugal force. 6. The method for producing a ceramic porous body according to claim 1, wherein the gel-like porous molded body is a gel-like porous molded body in which pores are inclined and oriented. 7. An average pore diameter of 0.1 μm in a range of 1 μm from the surface.
A porous ceramic body having pores having a diameter of 100 μm or more and less than 100 μm, and pores having an average pore diameter of 100 μm or more and 3000 μm or less.