JP2013079172A - Ceramic porous body and method for producing ceramic porous body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceramic porous body having uniform spherical pores formed in a spherical shape originated in air bubbles and to provide a method for producing ceramic porous body by which the ceramic porous body having uniform spherical pores can be produced.SOLUTION: The method for producing ceramic porous body produces a ceramic porous body having the spherical pores, which is composed of a calcium phosphate-based compound. The method includes: a first step of preparing slurry containing powders composed of the calcium phosphate-based compound, a water-soluble polymer compound and an alkylbenzene sulfonate surfactant; a second step of heating the slurry by high-frequency heating for gelation after foaming by stirring the slurry; and a third step of drying the gelated slurry and further sintering it.

Description

  The present invention relates to a ceramic porous body and a method for producing a ceramic porous body.

  In recent years, bone substitutes used for artificial bones, artificial teeth, bones, etc. in dentistry, surgery, etc. are non-toxic, have sufficient mechanical strength, and have high affinity with biological tissues and are easy to bind. More specifically, a ceramic porous body composed of a calcium phosphate compound is preferably used.

  As a method for producing a ceramic porous body (bone filling material) composed of such a calcium phosphate compound, for example, a raw material powder composed of a calcium phosphate compound and a pyrolytic substance are mixed and molded into a predetermined shape. In addition to the raw material powder and the pyrolytic substance, a foaming agent is further mixed in addition to the method of heating to remove the pyrolytic substance and sintering the raw material powder (see, for example, Patent Document 1). A method (for example, refer to Patent Document 2) of removing a pyrolyzed substance and sintering a raw material powder in a state where bubbles are generated by a foaming agent has been proposed.

  However, in these production methods, since the pyrolysis substance added to form pores does not always come into almost uniform contact, most of the formed pores often become independent pores, The variation in pore diameter of the formed pores is large. Furthermore, even if adjacent pores are in contact with each other and a communication hole in which the pores communicate with each other is formed, the cross-sectional area of the communication hole is small and the variation thereof is large.

  Therefore, even if the bone grafting material having such a structure is filled in a bone defect part or the like of a living body, it is difficult to uniformly enter osteoblasts and the like necessary for bone generation into the pores. There is a problem that reproduction cannot be realized.

Japanese Patent Laid-Open No. 60-21863 JP 2000-302567 A

  An object of the present invention is to provide a method for producing a ceramic porous body capable of producing a ceramic porous body having uniform spherical pores, and a ceramic porous body having uniform spherical pores.

Such an object is achieved by the present invention described in the following (1) to (6).
(1) A method for producing a porous ceramic body comprising a calcium phosphate compound and having spherical pores,
A first step of preparing a slurry comprising a powder composed of a calcium phosphate-based compound, a water-soluble polymer compound, and an alkylbenzene sulfonic acid-based surfactant;
A second step in which the slurry is foamed by stirring and then gelled by heating the slurry by high-frequency heating;
And a third step of drying and further sintering the gelled slurry.

  In this way, in the second step, the slurry is heated by high-frequency heating so that the slurry is uniformly gelled. Therefore, the ceramic porous body obtained in the third step has uniform spherical pores. Can be.

(2) The method for producing a porous ceramic body according to (1), wherein the water-soluble polymer compound is a cellulose derivative.
Thereby, gelatinization of a slurry can be performed more reliably.

  (3) The method for producing a ceramic porous body according to (1) or (2), wherein in the second step, the temperature at which the slurry is gelled is 80 ° C. or higher and 100 ° C. or lower.

  Thereby, the slurry can be surely gelled while preventing the water from boiling.

  (4) In the first step, after obtaining the dispersion containing the powder, the slurry is added with a paste containing the water-soluble polymer compound and the alkylbenzene sulfonic acid surfactant. The method for producing a ceramic porous body according to any one of the above (1) to (3), which is prepared by the method described above.

  In this way, the dispersion and paste are prepared separately and then mixed to obtain a slurry, whereby the paste is uniformly dispersed with respect to the powder contained in the dispersion. Therefore, the ceramic porous body obtained in the third step can have more uniform spherical pores.

  (5) The method for producing a porous ceramic body according to (4), wherein the temperature of the paste is set to be 10 to 20 ° C. higher than the temperature of the dispersion when the slurry is prepared.

  Thereby, the ceramic porous body obtained in the third step has more uniform spherical pores.

(6) A ceramic porous body composed of a calcium phosphate compound and having spherical pores,
Its relative porosity is 50% or more,
The spherical porous body has an average pore diameter of 100 to 160 μm and a standard deviation of 40 μm or less.

  It can be said that a ceramic porous body having spherical pores having such an average pore diameter and standard deviation has uniform spherical pores.

  According to the method for producing a ceramic porous body of the present invention, ceramics having a relative porosity of 50% or more, an average pore diameter of spherical pores of 100 to 160 μm, and a standard deviation of 40 μm or less. A porous body can be produced.

  Further, if the ceramic porous body of the present invention, it can be said that the spherical pores forming a spherical shape is uniform. For example, when this ceramic porous body is applied to a bone grafting material, cells such as osteoblasts. Since the movement is performed smoothly, early bone regeneration can be realized.

It is a scanning micrograph in the ceramic porous body (sintered body of Example 1) of this invention. 3 is a scanning micrograph of a sintered body of Comparative Example 1.

  Hereinafter, the manufacturing method of the ceramic porous body of this invention and suitable embodiment of a ceramic porous body are described in detail.

First, the ceramic porous body of the present invention will be described.
FIG. 1 is a scanning micrograph of the ceramic porous body of the present invention.

  The ceramic porous body of the present invention is composed of a calcium phosphate-based compound and has spherical spherical pores, the relative porosity of which is 50% or more, and the spherical pores have an average pore diameter of 100. ˜160 μm, and its standard deviation is 40 μm or less.

  Such a ceramic porous body can be used for a carrier used for culturing cells and biological tissues, and an artificial biomaterial having biocompatibility suitable for bone filling.

  In particular, when applied to a bone grafting material for bone filling, in the present invention, the average pore diameter of the spherical pores is 100 to 160 μm, and the standard deviation thereof is 40 μm or less, and the spherical pores are uniform. It has become a thing. Therefore, generation | occurrence | production of the lump comprised with a calcium-phosphate type compound can be reduced, and the communicating hole formed when the said spherical pores communicate also becomes uniform. As a result, osteoblasts and the like necessary for bone generation can be uniformly infiltrated into the spherical pores, and as a result, uniform bone regeneration can be realized.

  The relative porosity of the ceramic porous body may be 50% or more, but is preferably 55% or more, and more preferably 60% or more. By setting the relative porosity within such a range, the spherical pores are reliably communicated with each other to form a communication hole, and as a result, a pore structure in which the communication holes are three-dimensionally connected is formed.

  The average pore diameter of the spherical pores may be 100 to 160 μm, preferably 120 to 150 μm, and more preferably 130 to 150 μm. Furthermore, the standard deviation may be 40 μm or less, but is preferably 35 μm or less, and more preferably 30 μm or less.

  In addition to the standard deviation described above, the degree of variation in the pore diameter of the spherical pores can be expressed by, for example, the half-value width of the pore diameter. In the present invention, the half-value width is preferably 110 μm or less. 100 μm or less is more preferable.

  By setting the average pore diameter, standard deviation, and full width at half maximum within such ranges, it can be said that the spherical pores are more uniform, and more uniform bone regeneration can be realized.

In the present specification, “relative porosity” represents a ratio (%) of pores in the ceramic porous body. For example, (1-W / D / V) × 100, where W is dry weight, V is volume, D is representative of the theoretical density (e.g., hydroxyapatite 3.16g / cm ^3, β-TCP is 3.07g / cm ^3). ] Can be obtained from the relational expression.

  In addition, in this specification, “spherical pores” are, as shown in FIG. 1, spherical pores formed from bubbles, polymer spherical beads, and the like in a ceramic porous body. The pore diameter can be obtained, for example, by acquiring an image at a predetermined thickness using a micro CT apparatus or the like and measuring the image based on the image. And the average pore diameter, standard deviation, and half value width can be calculated | required from the measured pore diameter of each spherical pore.

  In addition, the image analysis for calculating | requiring the pore diameter of a spherical pore is performed by measuring a pore diameter as an equivalent circle diameter from a SEM image, for example.

  Further, in such a ceramic porous body, adjacent spherical pores communicate with each other to form a communication hole (see FIG. 1). The average particle diameter of the communication hole is 50 μm or more. Preferably, it is 50 μm or more and 150 μm or less. By setting the average particle diameter of the communication holes within such a range, while maintaining the strength required as a ceramic porous body, movement of precursor cells involved in bone formation between the spherical pores via the communication holes, Since the invasion of the nutritional vascular system is performed smoothly, early bone regeneration can be realized.

  Moreover, this ceramic porous body is comprised with the aggregate | assembly of the spherical secondary particle which consists of a granulated body of the primary particle comprised with a calcium-phosphate type compound. For this reason, the spherical pores are configured to have pores formed on the surface by the gaps between the spherical secondary particles. In the ceramic porous body having such a configuration, the pores preferably have a diameter of 20 μm or less, and more preferably 10 μm or less. By setting the pore diameter within such a range, it is possible to reliably maintain the bone regeneration ability required for a ceramic porous body artificial bone.

  When such a ceramic porous body is used as the above-mentioned bone grafting material, a granular material is often used. For example, the ceramic porous body may have a shape such as a cube, a rectangular parallelepiped, a cylinder, and a stick.

  Such a ceramic porous body is composed of a calcium phosphate compound having excellent biocompatibility.

  Examples of calcium phosphate compounds include apatites such as hydroxyapatite (HAP), fluorine apatite, and carbonate apatite, dicalcium phosphate, tricalcium phosphate (TCP), tetracalcium phosphate, and octacalcium phosphate. These can be used alone or in combination of two or more. Of these calcium phosphate compounds, those having a Ca / P ratio of 1.0 to 2.0 are preferred, and those having a Ca / P ratio of 1.5 to 2.0 are more preferred.

  The ceramic porous body of the present invention as described above can be manufactured by the following method for manufacturing a ceramic porous body of the present invention.

  The method for producing a ceramic porous body according to the present invention comprises preparing a slurry containing the spherical secondary particle powder composed of a calcium phosphate compound, a water-soluble polymer compound, and an alkylbenzene sulfonic acid surfactant. Step 1, the second step of foaming the slurry by stirring, and then gelling the slurry by heating by high-frequency heating, and drying and further sintering the gelled slurry And a third step. Hereinafter, these steps will be sequentially described.

  [A] First, a slurry containing a powder composed of a calcium phosphate compound, a water-soluble polymer compound, and an alkylbenzene sulfonic acid surfactant is prepared.

  The slurry is not particularly limited as long as it contains the powder, a water-soluble polymer compound, and an alkylbenzene sulfonic acid surfactant, and further, a preparation method for preparing the slurry. Similarly, there is no particular limitation, but a paste containing a water-soluble polymer compound and an alkylbenzene sulfonic acid surfactant is added to a dispersion (slurry) containing a powder composed of a calcium phosphate compound. Is preferred. This makes it possible to uniformly disperse the paste (binder that forms a paste) in the dispersion (powder).

Hereinafter, the case where slurry is prepared by such a method will be described as an example.
[A-1] First, a dispersion (slurry) containing powder composed of a calcium phosphate compound is prepared.

  Although it does not specifically limit as this powder, The secondary particle | grains with an average particle diameter of 0.5-80 micrometers consisting of primary particles with an average particle diameter of 100 nm or less are used preferably.

  And this dispersion liquid (slurry) is obtained by disperse | distributing this powder to water etc., for example.

  [A-2] Next, a paste (binder that forms a paste) containing a water-soluble polymer compound and an alkylbenzene sulfonic acid surfactant is prepared.

  For example, the paste can be made into a paste by adding a predetermined amount of an alkylbenzene sulfonic acid surfactant to a water-soluble polymer compound.

  In addition, when the viscosity of this paste is high, you may make it adjust the viscosity by adding solvents, such as water.

  The water-soluble polymer compound is such that the water-soluble or water-dispersed solution is gelled by applying means such as heating. Here, the water-soluble or aqueous dispersion may be any of an aqueous solution, a colloidal solution, an emulsion and a suspension.

  Examples of such water-soluble polymer compounds include cellulose derivatives such as methylcellulose, polysaccharides such as curdlan, synthetic polymers such as polyvinyl alcohol, polyacrylic acid, polyacrylamide, and polyvinylpyrrolidone. Derivatives are preferred. Thereby, gelatinization of a slurry can be performed more reliably.

  In addition, the alkylbenzene sulfonic acid-based surfactant is added to suppress or prevent disappearance of the generated bubbles while generating finer bubbles when the slurry is stirred in the next step [B]. It is what is done.

  Furthermore, in the present invention, an alkylbenzene sulfonic acid surfactant is used as the surfactant. By using such a surfactant, this is constituted when a sintered body is obtained in the post-process [C]. The calcium phosphate compound to be introduced may have a sulfate group introduced therein. Therefore, cell activity of osteoblasts and the like increases during bone generation, and as a result, bone regeneration in the bone grafting material can be performed earlier. Furthermore, in the next step [B], when the slurry is heated by high-frequency heating, since the impedance of the slurry is lowered, the slurry can be heated with high efficiency.

  The alkylbenzene sulfonic acid surfactant is not particularly limited, and examples thereof include alkylbenzene sulfonic acid EDT.

  [A-3] Next, the paste prepared in [A-2] is added to the dispersion prepared in [A-1] to obtain a slurry (dispersion with the paste added).

  Thus, separately preparing the dispersion and paste, and then mixing them, without causing bubbles or powder lump in the slurry obtained by mixing them, The paste (binder that forms a paste) can be uniformly dispersed in the dispersion (powder). Therefore, the sintered body (ceramic porous body) obtained in the post-process [C] has uniform spherical pores, that is, surely has the average pore diameter and standard deviation of the spherical pores as described above. be able to.

  In this case, it is preferable to add the paste several times to the dispersion in a predetermined amount.

  The temperature of the paste (paste-like binder) is preferably set higher than the temperature of the dispersion, and specifically, it is preferably set higher by about 10 to 20 ° C. More specifically, the temperature of the dispersion is preferably about 10 to 30 ° C. Moreover, it is preferable that the temperature of a paste is about 30-40 degreeC. Here, in the present invention, since it is necessary to set the relative porosity of the obtained ceramic porous body as high as 50% or more, a paste containing a high concentration water-soluble polymer compound is added. Therefore, depending on the type of the water-soluble polymer compound, if the paste is added to the dispersion at a normal temperature, the paste has a high viscosity, and thus it may be difficult to uniformly mix the paste in the dispersion. is there.

  Therefore, by setting the temperature of the paste higher than the temperature of the dispersion liquid as described above, the viscosity of the paste can be reduced, and thus the paste can be mixed more uniformly in the dispersion liquid. As a result, the sintered body obtained in the post-process [C] has the average pore diameter and standard deviation of the spherical pores as described above more reliably.

  In the dispersion (slurry) to which the paste has been added, the powder is 100 parts by weight, the water-soluble polymer compound is 1 to 10 parts by weight, and the alkylbenzene sulfonic acid surfactant is 1 to 10 parts by weight. Is preferred. If the added amount of the powder is too small, it may take more time than necessary for the drying time, and if it is too much, the viscosity of the slurry becomes too high and it may be difficult to generate foam. is there. Further, if the amount of the water-soluble polymer compound added is less than 1 part by weight, gelation is difficult, and if it is more than 10 parts by weight, the viscosity of the slurry is too high and foaming is difficult. Furthermore, if the addition amount of the alkylbenzene sulfonic acid surfactant is less than 1 part by weight, foaming is difficult, and even if it exceeds 10 parts by weight, no improvement in the effect can be obtained.

  [B] Next, the obtained slurry (dispersion to which the paste has been added) is foamed by stirring, and then the slurry is gelled by heating with high frequency heating (second step).

  [B-1] First, the slurry obtained in the step [A] is foamed by stirring.

When the slurry is stirred, the slurry entrains air and foams due to this.
The stirring force for stirring the slurry at this time is not particularly limited, but is preferably 50 W / L or more. When the stirring force is less than 50 W / L, foaming may be insufficient depending on the type of powder and its content, and a ceramic porous body having a desired porosity may not be obtained.

  The stirring force can be obtained by [maximum output of stirrer (W) / amount of aqueous solution (L)] × (actual rotational speed / maximum rotational speed). Further, the output of the stirrer increases in order to maintain the rotational speed when the viscosity of the slurry becomes high, but when foaming to a high porosity, the slurry viscosity does not substantially change from the viscosity at the time of preparation. Therefore, the effect of viscosity is virtually negligible.

  As an apparatus that can obtain such a stirring force, for example, an impeller homogenizer may be mentioned. The impeller type homogenizer is originally designed so that foaming does not occur. However, when the stirring condition is 50 W / L or more, significant foaming is possible. Further, it is preferable to use a stirring device having a structure in which the stirring blade is formed in a disk shape, unevenness on the saw blade is provided on the outer periphery of the disk, and a baffle plate is provided on the inner wall of the stirring container.

Examples of the impeller homogenizer having such a structure include PH91, PA92, HF93, FH94P, PD96, and HM10 manufactured by SMT. Furthermore, in order to further promote the foaming, an inert gas such as air, nitrogen, or argon may be injected into the slurry being stirred.
The stirring time depends on the stirring force, but is generally set to about 1 to 30 minutes.

  Further, in order to make the bubbles fine and uniform and stabilize, foaming is preferably performed at a relatively low temperature, specifically, preferably about 0 to 25 ° C., more preferably about 5 to 20 ° C. Set to liquid temperature.

  [B-2] Next, the foamed slurry is gelled by heating by high-frequency heating.

  Thus, the present invention is characterized in that high-frequency heating is used as a heating method for gelling the foamed slurry.

  Here, the high frequency heating means that a dielectric loss is generated in the constituent material contained in the slurry by applying a high frequency to the foamed slurry, thereby generating heat.

  According to such high-frequency heating, accurate heating temperature control can be easily performed, and heating can be performed almost uniformly from the surface of the slurry to the inside thereof. For this reason, the gelation of the slurry is similarly performed almost uniformly from the surface of the slurry to the inside thereof, resulting in variations in the bubble diameter due to different times required for gelation. Can be accurately suppressed or prevented. Therefore, the bubbles contained in the gelled slurry have a uniform bubble diameter from the surface of the slurry to the inside thereof.

  Further, in the present invention, since an alkylbenzene sulfonic acid surfactant is used as the surfactant, the impedance of the slurry can be reduced, so that the slurry can be heated with high efficiency.

  Specifically, this gelation is performed by heating a slurry sufficiently foamed by stirring, for example, by high-frequency heating, preferably 80 ° C. or higher and 100 ° C. or lower, more preferably 80 ° C. or higher and 90 ° C. or lower. By doing so, it is performed by the action of a water-soluble polymer compound such as methylcellulose. Depending on the type of the water-soluble polymer compound and the like, if the heating temperature is less than the lower limit, gelation may be insufficient, and if the heating temperature exceeds the upper limit, moisture will boil and the formed pores The structure may be destroyed.

  [C] Next, the gelled and foamed slurry is dried and further sintered (third step).

  [C-1] First, the dried slurry (green block) is obtained by drying the gelled slurry.

  In addition, drying of the gelatinized slurry is performed by holding at a high temperature (for example, 80 ° C. or more and less than 100 ° C.) such that moisture does not boil.

  In addition, the gelled slurry (gel) shrinks almost isotropically upon drying, and the bubbles do not change, and therefore have fine and uniform spherical spherical pores (macropores) without causing cracks or the like. It becomes a dry body (green block) with high strength.

  [C-2] Next, the dried body (green block) is sintered to obtain a sintered body (ceramic porous body of the present invention).

  The conditions for sintering the green block are, for example, sintering at a temperature of 1000 to 1250 ° C. for 2 to 10 hours. If the sintering temperature is less than 1000 ° C., a ceramic porous body having sufficient strength cannot be obtained, and if it exceeds 1250 ° C., when hydroxyapatite is used as the calcium phosphate compound, hydroxyapatite is tricalcium phosphate. And decompose into calcium oxide. The sintering time is appropriately set according to the sintering temperature.

  When β-TCP is to be obtained as the calcium phosphate compound, the temperature for sintering the green block is set within a range of 1000 to 1150 ° C. This reliably prevents the transition from β-TCP to α-TCP.

  Prior to this step [C-2], a processing step for processing the dried body and / or a degreasing step for degreasing the dried body may be performed.

  In the processing step, the water-soluble polymer compound contained in the green block acts as a binder and thus has mechanical strength that can be handled. Therefore, cutting can be performed with the dried body without pre-baking.

  Moreover, a degreasing process can be performed by heating a green block at 300-900 degreeC, for example. Thereby, the water-soluble polymer compound and the alkylbenzene sulfonic acid surfactant can be reliably removed from the green block.

  In addition, when performing a degreasing process and a sintering process collectively, what is necessary is just to make it heat up gradually until it reaches sintering temperature. For example, the temperature is raised from room temperature to about 600 ° C. at a temperature raising rate of about 10 to 100 ° C./hour, and then raised to the sintering temperature at a temperature raising rate of about 50 to 200 ° C./hour and held at this temperature. Can be done.

  The method for producing a ceramic porous body and the ceramic porous body of the present invention have been described above, but the present invention is not limited to this.

  For example, in the method for producing a ceramic porous body according to the present invention, for any purpose, the previous step of step [A], between steps [A] and [B], between steps [B] and [C]. An intermediate step that exists or a post-step of step [C] may be added.

  Furthermore, the ceramic porous body of the present invention is not only applied to artificial biomaterials, but also used as, for example, a liquid chromatography filler, catalyst carrier, various electric / electronic materials, nuclear reactor materials, ceramic heating elements, and the like. You can also.

Next, specific examples of the present invention will be described.
1. Production of porous ceramic body (Example 1)
<1> First, a slurry containing 100 parts by weight of secondary particles (average particle size: 25 μm) composed of granules of primary particles (average particle size: 100 nm) with a Ca / P ratio of 1.67 was prepared and homogenizer. ("SM92", "PA92").

  <2> Next, 3.4 parts of methylcellulose powder was added to an aqueous solution in which 1.4 parts of alkylbenzene sulfonic acid surfactant (alkylbenzene sulfonic acid EDT) was added to 27 parts of pure water, and stirred deaerator (Sinky) , “Awatori Nertaro ARE-250”) to prepare a paste-like binder.

  <3> Next, by adding the paste-like binder prepared in the step <2> to the slurry prepared in the step <1>, a slurry to which the paste-like binder was added was obtained. In this case, the temperatures of the slurry and the paste-like binder were 20 ° C. and 35 ° C., respectively.

<4> Next, foaming was performed after the paste-like binder was completely dispersed.
<5> Next, the obtained bubble-containing slurry was heated by high-frequency heating to be gelled at 85 ° C. In addition, the high frequency heating was performed by heating up to 85 degreeC with the temperature increase rate of 6.0 degreeC / min using the high frequency heating apparatus (made by Fuji radio industry).

  <6> Next, the obtained gel was dried by holding at 85 ° C. using a hot air dryer (manufactured by Trio Science), thereby obtaining a green block (block before sintering).

  <7> Next, after processing the green block into a shape of 14 mm × 14 mm × 14 mm, the green block is sintered in the atmosphere at 1200 ° C. for 4 hours, thereby being formed of hydroxyapatite (HAp). A sintered body of 10 mm × 10 mm was obtained.

(Comparative Example 1)
In the step <5>, the heating of the bubble-containing slurry is hot air heating using a hot air dryer (manufactured by Trio Science) instead of high-frequency heating, and the inside of the bubble-containing slurry is heated to 85 ° C., In the same manner as in Example 1, a sintered body of Comparative Example 1 composed of HAp was obtained.

(Comparative Example 2)
In the step <2>, a fatty acid alkanolamide surfactant (N, N-dimethyldodecylamine oxide) is used instead of the alkylbenzene sulfonic acid surfactant, and the heating is increased by high frequency heating in the step <5>. A sintered body of Comparative Example 2 composed of HAp was obtained in the same manner as in Example 1 except that the temperature rate was 3.5 ° C./min.

2. Evaluation 2-2. Evaluation of pore distribution in ceramic porous body The cut surfaces in the sintered bodies of Example 1 and Comparative Examples 1 and 2 were imaged by SEM, and the obtained images were subjected to image analysis to obtain the average pore diameter and standard deviation of spherical pores. The full width at half maximum and the average pore diameter and standard deviation of the communicating holes were determined, respectively.

  In addition, the image analysis is performed by measuring the pore diameter of each spherical pore as well as the pore diameter of the communication hole by measuring on Photoshop as the equivalent circle diameter based on the image result taken by SEM, and based on the result, The average pore diameter, standard deviation and half width of each spherical pore, and the average pore diameter and standard deviation of each communicating hole were determined.

The results are shown in Table 1.
For Example 1 and Comparative Example 1, SEM photographs used for image analysis are shown for reference (see FIGS. 1 and 2).

  As is clear from Table 1, in the sintered body of Example 1 composed of HAp, the average pore diameter of the spherical pores is 100 to 160 μm, and the standard deviation is 40 μm or less. This resulted in increased porosity uniformity.

  On the other hand, in the sintered bodies of Comparative Examples 1 and 2, both the average pore diameter and the standard deviation were outside the above ranges, and the uniformity of the spherical pores was low.

Claims (6)

A method for producing a ceramic porous body comprising a calcium phosphate compound and having spherical pores,
A first step of preparing a slurry comprising a powder composed of a calcium phosphate-based compound, a water-soluble polymer compound, and an alkylbenzene sulfonic acid-based surfactant;
A second step in which the slurry is foamed by stirring and then gelled by heating the slurry by high-frequency heating;
And a third step of drying and further sintering the gelled slurry.   The method for producing a porous ceramic body according to claim 1, wherein the water-soluble polymer compound is a cellulose derivative.   3. The method for producing a porous ceramic body according to claim 1, wherein in the second step, the temperature at which the slurry is gelled is 80 ° C. or higher and 100 ° C. or lower.   In the first step, the slurry is prepared by adding a paste containing the water-soluble polymer compound and the alkylbenzene sulfonic acid surfactant after obtaining a dispersion containing the powder. The method for producing a ceramic porous body according to any one of claims 1 to 3.   5. The method for producing a ceramic porous body according to claim 4, wherein the temperature of the paste is set to be 10 to 20 ° C. higher than the temperature of the dispersion when the slurry is prepared. A ceramic porous body composed of a calcium phosphate compound and having spherical pores,
Its relative porosity is 50% or more,
The spherical porous body has an average pore diameter of 100 to 160 μm and a standard deviation of 40 μm or less.

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