Slurry for manufacturing a ceramic porous body and a method for manufacturing a ceramic porous body using the same

Abstract

The present invention provides a slurry for manufacturing a ceramic porous body comprising ceramic powder, a binder, a foaming agent, cellulose fibers, and a solvent. The ceramic porous body, such as a bone graft material or scaffold manufactured according to the present invention, is characterized by being able to improve mechanical strength by increasing the stabilization of the homogeneous pore structure and shape due to the influence of the added binder and cellulose fibers, and having a porosity of 65% or more, making it mechanically processable.

Description

Technology Field

[0001] The present invention relates to a slurry for manufacturing a ceramic porous body and a method for manufacturing a ceramic porous body using the same. Specifically, it is a technology that improves the low mechanical strength and pore stability of wet porous bodies and dried porous bodies, which were problematic when directly foaming existing ceramic slurries, in a relatively simple manner. The ceramic porous body, such as a bone graft material or scaffold manufactured according to the present invention, is characterized by being able to improve mechanical strength by increasing the stabilization of the homogeneous pore structure and shape due to the influence of added cellulose fibers, and having a porosity of 65% or more, making it mechanically processable. Background Technology

[0003] Porous ceramics refer to solids in which pores of various sizes are distributed within lumps, granules, or particles, and are also called porous bodies, porous solids, or porous materials. Generally, the pore size of artificially manufactured porous ceramics ranges from approximately 1 μm to 10 mm, and their shapes vary, but these characteristics differ depending on the manufacturing method.

[0004] When classified by the geometric structure of the pores, these porous ceramics can be broadly divided into aggregate, sponge or foam, and honeycomb types.

[0005] Depending on the material, pore size, and shape of porous ceramics, they are used in various applications such as filtration or diffusion filters, media catalysts, sound absorbers, DPFs, heat exchangers, special heaters, bone graft materials, or scaffolds.

[0007] Traditional porous ceramics are manufactured by mixing a certain amount of flux material into ceramic particles with a particle size distribution controlled within a certain range, molding them, and then melting the flux through high-temperature treatment to aggregate the ceramic particles to produce a porous ceramic body, or by compression molding ceramic particles of a desired particle size and then partially sintering them at a temperature lower than the sintering temperature to obtain a porous body.

[0008] Pores are formed from micropores within the particles and macropores between the particles, and the size of the pores between the particles is related to the size of the raw material particles. These methods not only make it difficult to effectively control the pore size and distribution of the porous body, but also have the problem of making it difficult to increase the porosity to more than 50%.

[0009] In addition, sponge replication is used to manufacture sponge-type porous bodies. This method is a technique for manufacturing porous bodies by coating a polyurethane sponge with a ceramic slurry. It allows for obtaining porous bodies with desired pore size and distribution and high porosity. While this is advantageous for the deposition of initial bone cells and the delivery and growth of bone tissue when used as a bone graft material, it is not suitable for mass production, has low mechanical strength, and causes environmental pollution problems due to toxic gases generated during the thermal decomposition process of the polyurethane sponge.

[0010] Consequently, due to global environmental regulations, a new method for manufacturing porous bodies has become necessary compared to the aforementioned manufacturing method. Among various alternatives, direct foaming technology using a slurry is attracting significant attention as a method for manufacturing ceramic porous bodies with relatively large pores. There is a demand for a technology that can create a microstructure with stable, interconnected pores similar to natural bone at a low manufacturing cost while minimizing the use of binders or organic pore-forming agents. Prior art literature

[0012] Korean Patent Publication 10-2022-0051042 (2022.04.26.) The problem to be solved

[0013] One objective of the invention is to provide a slurry for manufacturing a ceramic porous body and a method for manufacturing a ceramic porous body using the same, which can solve the problem of low mechanical strength that was an issue in conventional direct foaming methods and the formation of stable and interconnected pores, and reduce manufacturing costs by simplifying the manufacturing process compared to existing methods.

[0015] The problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art from the description below. means of solving the problem

[0017] According to a first aspect for achieving the above objective, the present invention provides a slurry for manufacturing a ceramic porous body comprising ceramic powder, an organic binder, a foaming agent, cellulose fibers, and a solvent.

[0018] Preferably, the ceramic powder may be characterized by comprising at least one of hydroxyapatite (HA), β-tricalcium phosphate (β-TCP), alumina, zirconia, or dental porcelain.

[0019] Preferably, the organic binder may be characterized by comprising at least one of starch, dextrin, wax, paraffin, methylcellulose (MC) or carboxymethylcellulose (CMC), lignosulfonate, polyacrylic acid (PA), polyvinyl alcohol (PVA), and polyethylene glycol (PEG).

[0020] Preferably, the foaming agent may be characterized by comprising at least one of propyl gallate, butyl gallate, hexyl amine, butyric acid, valeric acid, lauryl betaine, or coco-betaine.

[0021] Preferably, the length of the cellulose fiber may be characterized as being 10 to 100,000 nm.

[0022] Preferably, the slurry for manufacturing the ceramic porous body may be characterized by comprising 30 to 70 parts by weight of a solvent for every 100 parts by weight of the total amount of the ceramic powder, binder, foaming agent powder, and cellulose fiber combined.

[0023] Preferably, the solvent may be characterized as being distilled water.

[0025] According to a second aspect for achieving the above objective, the present invention provides a method for manufacturing a ceramic porous body comprising: a step of mixing a binder aqueous solution prepared by mixing a binder and distilled water with ceramic powder; a step of adding a foaming agent to the slurry; a step of preparing a slurry for manufacturing a ceramic porous body by mixing cellulose fibers into the slurry for manufacturing a ceramic porous body; a foaming step of forming uniform pores by stirring the slurry for manufacturing a ceramic porous body; a molding step of pouring the slurry for manufacturing a ceramic porous body into a mold to form a desired shape and a drying step of drying to have stable pores; and a sintering step of imparting mechanical strength to the dried porous body.

[0027] Preferably, the drying step may be characterized by proceeding slowly at room temperature. Effects of the invention

[0029] The slurry for manufacturing a ceramic porous body according to the present invention and the method for manufacturing a ceramic porous body using the same can solve the problem of low mechanical strength that was an issue in conventional direct foaming methods and the formation of stable and interconnected pores, and by simplifying the manufacturing process compared to conventional methods, it is possible to reduce manufacturing costs and manufacture a ceramic porous body with homogeneous pore shape and size. Brief explanation of the drawing

[0031] FIG. 1 is a diagram showing the flow of a method for manufacturing a porous body by direct foaming as an embodiment of the present invention. Figure 2 is a photograph showing the surface change of the HA porous body during the manufacturing process and the amount of μm cellulose fiber added as an example of the present invention. Figure 3 is a diagram showing the amount of μm cellulose fibers added and the changes in pore size and distribution of the cross-section of the HA porous body during the manufacturing process as an embodiment of the present invention. Figure 4 is a diagram showing the pore structure of a cross-section of a porous body after sintering according to the amount of μm cellulose fiber added as an embodiment of the present invention. FIG. 5 shows the change in compressive strength of a sintered porous body according to the amount of binder added at a constant P / L ratio (=0.4) as an embodiment of the present invention (sintering temperature 1200 This is a drawing showing the sintering time (2 hours). FIG. 6 is a diagram showing pore formation and changes in porous body shape according to the amount of binder added at a constant P / L ratio (=0.4) as an embodiment of the present invention. FIG. 7 is a diagram showing the change in pore shape of a sintered porous body (1200°C, 2 hours) according to the stirring speed when preparing a slurry with a constant amount of binder (0.4 wt%), foaming agent (0.4 wt%), and P / L ratio (=0.4) to HA powder as an embodiment of the present invention. Specific details for implementing the invention

[0032] The foregoing and additional aspects are embodied through embodiments described with reference to the attached drawings. It is understood that the components of each embodiment may be combined in various ways within the embodiment or with components of other embodiments, unless otherwise stated or contradicted. Based on the principle that the inventor can appropriately define the concepts of terms to best describe his invention, the terms used in this specification and claims shall be interpreted in a meaning and concept consistent with the description or proposed technical idea.

[0033] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete, and to ensure that the spirit of the present invention is sufficiently conveyed to those skilled in the art. Throughout the specification, identical reference numerals indicate identical components, and components marked with identical or similar symbols perform identical or similar functions, so their description may be omitted. For components with reference numerals for which description has been omitted, reference may be made to the descriptions previously given for components with identical or similar symbols.

[0035] According to a first aspect for achieving the above objective, the present invention provides a slurry for manufacturing a ceramic porous body comprising ceramic powder, a binder, a foaming agent, cellulose fibers, and a solvent.

[0036] Stable pores can be formed by including the above foaming agent.

[0037] The basic structure of a ceramic porous body manufactured by including the above ceramic powder can be formed.

[0038] The shape and stabilization of the pores of the ceramic porous body manufactured by including the above cellulose fibers can be enhanced.

[0041] Preferably, the ceramic powder may be characterized by comprising at least one of hydroxyapatite (HA), β-tricalcium phosphate (β-TCP), alumina, zirconia, or dental porcelain.

[0042] The ceramic powder above can be used to manufacture bone graft materials or scaffolds requiring excellent biocompatibility by including at least one of hydroxyapatite (HA) or β-tricalcium phosphate (β-TCP), which are calcium phosphate-based minerals.

[0043] The above ceramic powder can be used to manufacture artificial teeth or artificial joints requiring mechanical strength and wear resistance by including at least one of alumina, zirconia, or dental porcelain.

[0045] Preferably, the organic binder may be characterized by comprising at least one of starch, dextrin, wax, paraffin, methylcellulose (MC) or carboxymethylcellulose (CMC), lignosulfonate, polyacrylic acid (PA), polyvinyl alcohol (PVA) or polyethylene glycol (PEG).

[0046] In the present invention, a binder solution was prepared and used by mixing 0.1 to 1.0 parts by weight of CMC among the organic binders with 100 parts by weight of distilled water in the step of preparing the aqueous binder solution. This trace amount of binder serves to aggregate the ceramic powder, thereby improving the excellent pore structure and the mechanical stability of the wet porous body by capturing the gas generated during foaming. The amount of CMC added is preferably 0.3 to 0.7%, and most preferably 0.4%, relative to the weight of the ceramic powder, which can be most effective.

[0047] If the amount of CMC added is lower than 0.3%, the binder effect is reduced, resulting in low drying strength and cracking, and if it is higher than 0.7%, it may lead to a decrease in strength after sintering.

[0048] To make the slurry for manufacturing the ceramic porous body, the mixing ratio of the ceramic powder and the prepared aqueous binder solution may be characterized by comprising 30 to 70 parts by weight of solvent per 100 parts by weight of ceramic.

[0049] Preferably, the foaming agent may be characterized by comprising at least one of propyl gallate, butyl gallate, hexyl amine, butyric acid, valeric acid, lauryl betaine, or coco-betaine.

[0050] Any foaming agent may be used as the foaming agent above, but in the present invention, cocobetaine was used as the foaming agent. The amount of cocobetaine foaming agent added is preferably 0.01 to 0.2 parts by weight per 100 parts by weight of binder solution, and most preferably 0.03 to 0.08 parts by weight was most effective. If the amount of foaming agent added is less than 0.01 parts by weight, only some of the ceramic particles become hydrophobic, resulting in poor pore formation; if it exceeds 0.2 parts by weight, a large amount of foaming agent that does not adhere to the ceramic particles exists, which may prevent the formation of a porous body.

[0051] Preferably, the length of the cellulose fiber may be characterized as being 10 to 100,000 nm.

[0052] The length of the above cellulose fibers is 10 to 100,000 nm (100 μm), and it is possible to add 0.1 to 4.0 parts by weight per 100 parts by weight of ceramic powder. However, it was most effective at 0.2 to 0.4 parts by weight. While the thinner or longer the cellulose fibers are, the more effective the same amount of fibers are added, fiber dispersion is very important because clumping occurs when the fibers are thin or long. In particular, the same problem occurs when an excessive amount of fibers is added. Well-dispersed cellulose fibers act as a bridging agent in the wet or dry porous body during foaming or drying of the slurry, increasing resistance to cracking and improving the stability of the porous body structure or pores. Finally, they volatilize during sintering and no longer remain within the porous body.

[0054] The above slurry for manufacturing the ceramic porous body is a mixture in which a solvent (L) is added to a solid powder (P) comprising a ceramic powder, a binder, a foaming agent powder, and cellulose fibers. The P / L ratio varies depending on the type of ceramic powder, but here, it is acceptable to calculate only the weight of the ceramic powder for the solid powder. The mixing ratio (P / L) of the powder and the binder aqueous solution was preferably 30 to 70 parts by weight of distilled water per 100 parts by weight of the powder, and 40 parts by weight was most suitable. If the amount of distilled water is less than 30 parts by weight, the ceramic powder and cellulose fibers may not be dispersed, and if it is greater than 70 parts by weight, it may be difficult to produce the shape of the ceramic porous body.

[0056] Hereinafter, the present invention for achieving the above objective will be described in other aspects. In the description of other aspects of the present invention below, any parts that overlap with the description according to the first aspect of the present invention may be deemed to be omitted even if they are not described.

[0057] According to a second aspect for achieving the above objective, the present invention provides a method for manufacturing a ceramic porous body comprising: a mixing step of mixing a binder aqueous solution prepared by mixing a binder and distilled water with ceramic powder; an addition step of mixing a foaming agent into the mixed slurry; a step of preparing a slurry for manufacturing a ceramic porous body by mixing cellulose fibers into the slurry; a foaming step of stirring the slurry for manufacturing a ceramic porous body to form uniform pores; a molding step of pouring the foamed slurry into a mold to form a desired shape; a drying step to ensure that the molded porous body has stable pores; and a sintering step to impart mechanical strength to the dried porous body.

[0058] FIG. 1 is a diagram showing the flow of a method for manufacturing a porous body by direct foaming as an embodiment of the present invention. As shown in the flowchart of the present invention, the process for manufacturing a ceramic porous body by direct foaming can be broadly divided into two stages: a ceramic slurry manufacturing stage and a ceramic porous body manufacturing stage, and each stage can be subdivided into four stages.

[0061] Preferably, the foaming step and the molding step may be characterized by forming a desired pore size and a desired porous body shape at room temperature.

[0062] The foaming step described above involves introducing air into a slurry containing added cellulose at room temperature using a stirrer to foam into pores of a desired size; this step is the foaming step that forms the pores. The introduced air is hydrophobic and separates from water, and ceramic particles that exhibit hydrophobicity due to surface treatment adhere to the area around the air bubbles, consequently forming a layer of ceramic particles on the outside of the air bubbles. The pattern of air injection varies depending on the stirring speed and time during pore formation, which allows for easy control of the pore size, shape, and distribution.

[0063] In the present invention, 500 to 700 rpm, preferably 570 to 620 rpm, is effective for forming pores of approximately 200 to 350 microns in size. For forming pores with a size of 350 to 550 μm, 500 to 700 RPM, preferably 630 to 680 rpm, is effective. The stirring time was appropriate for 2 to 10 minutes, but was preferably 4 to 6 minutes, and was most preferably 5 minutes.

[0065] In other words, when carried out under the above-mentioned optimized foaming conditions, it was possible to obtain a ceramic porous body having stability of pore shape and desired size and distribution.

[0069] Preferably, the molding and drying steps may be characterized by first pouring the foamed slurry into a mold to form a desired shape, and then slowly drying it at room temperature to create a stable porous body.

[0070] In the above molding step, the foamed slurry is poured into a mold; prior to pouring, it is necessary to verify that the slurry possesses the desired pore size and porosity. The slurry poured into the mold is placed in a dryer and 40 It was dried slowly for 2 to 4 days. To prevent cracking or collapse of the porous body during drying, it should be dried slowly and uniformly as much as possible; for this purpose, it was dried with the lid covered. The longer the drying time, the better to ensure safety from the risk of cracking, but 3 days or more was effective. Drying shrinkage was significantly reduced when a binder was used. This phenomenon is because the binder acts to firmly hold the ceramic powders together when forming the wet porous body.

[0071] Preferably, the sintering step may be characterized by heating the dried porous body to a sintering temperature according to a heating schedule to impart mechanical strength.

[0072] In the sintering step, to prevent cracking or collapse of the dried porous body due to the rapid volatilization of the binder, foaming agent, and cellulose fibers during heating, the temperature is gradually increased from room temperature to 700°C at a rate of 1°C per minute, then increased at a rate of 5°C per minute, maintained at the sintering temperature for 1 hour, and then slowly cooled in the furnace. Here, the sintering temperature is 1000 to 1500°C depending on the ceramic material. It is preferable that, in the case of HA, it is preferably 1100 to 1300 , most preferably 1200 It is effective, and the sintering time is 1200 It is preferable to sinter for 1 to 4 hours, and more preferably, sintering for 2 hours is most effective. The bone graft material or scaffold produced by this manufacturing process is characterized by a relatively homogeneous pore structure and shape, a porosity of 65% or more, and significantly improved mechanical strength (>10 MPa).

[0074] The present invention will be explained in more detail below through examples. However, the present invention should not be interpreted restrictively by the following examples.

[0076] Example 1 - Preparation of a slurry for manufacturing a ceramic porous body

[0077] The process for manufacturing a slurry for a ceramic porous body is as follows. Here, the slurry for manufacturing a ceramic porous body may be characterized by comprising 30 to 70 parts by weight of an aqueous binder solution per 100 parts by weight of ceramic powder (HA).

[0078] (1) A binder solution preparation step in which an organic binder and distilled water are mixed to prepare a binder solution; a binder solution was prepared and used by mixing 0.1 to 1.0 parts by weight of CMC among the organic binders with 100 parts by weight of distilled water. The amount of CMC added can be 0.1 to 1.0% with respect to the weight of the ceramic powder, but is most effective when it is preferably 0.3 to 0.7%, and most preferably 0.4%. If the amount of CMC added is lower than 0.3%, cracks occur during drying, and if it is higher than 0.7%, it results in a decrease in compressive strength.

[0079] (2) A step of preparing a ceramic slurry by mixing HA ceramic powder into the above aqueous solution; it is preferable to include 30 to 70 parts by weight of binder aqueous solution for every 100 parts by weight of HA ceramic powder, but 40 parts by weight is most effective.

[0080] (3) A step of preparing a ceramic slurry with added foaming agent by adding a foaming agent to the above HA slurry; preferably, the amount of cocobetaine as the foaming agent is 0.01 to 0.2 parts by weight per 100 parts by weight of the binder aqueous solution, and most preferably 0.03 to 0.08 parts by weight was most effective. When the amount of foaming agent added is less than 0.01 parts by weight, only some of the ceramic particles become hydrophobic, resulting in poor pore formation, and when it exceeds 0.2 parts by weight, a large amount of foaming agent that does not adhere to the ceramic particles exists, so the formation of a porous body is not achieved.

[0081] (4) A manufacturing step of mixing cellulose fibers into the ceramic slurry to create a slurry (suspension) for manufacturing a ceramic porous body; the length of the cellulose fibers is 10 to 100,000 nm (100 μm), and it is possible to add 1.0 to 4.0 parts by weight per 100 parts by weight of ceramic powder. The thinner or longer the cellulose fibers are, the more effective the addition of the same amount of fibers is; however, as the fibers become thinner or longer, clumping occurs, so the dispersion of the fibers is very important. Well-dispersed cellulose fibers act as a bridging agent in the wet or dry porous body during foaming or drying of the slurry, increasing resistance to cracking and improving the stability of the porous body structure or pores. Finally, they volatilize upon sintering and no longer remain in the porous body.

[0083] Example 2 - Preparation of a ceramic porous body

[0084] The process of manufacturing a ceramic porous body using the above-mentioned slurry for manufacturing a ceramic porous body is as follows.

[0085] (1) A foaming step in which a slurry for manufacturing the ceramic porous body is stirred to form uniform pores; a foaming step in which air is introduced into the slurry using a stirrer at room temperature to foam the slurry containing cellulose to form pores of a desired size. In the present invention, 500 to 700 RPM, preferably 570 to 620 RPM, is effective for forming pores of approximately 200 to 350 microns in size. 500 to 700 RPM, preferably 630 to 680 RPM, is effective for forming pores of 350 to 550 μm in size. The stirring time was appropriate for 2 to 10 minutes, but was preferably 4 to 6 minutes, and 5 minutes was most preferable. That is, when carried out under the above optimized foaming conditions, a ceramic porous body having stability of pore shape and a desired size and distribution could be obtained.

[0086] (2) A molding step of pouring the above-mentioned slurry for manufacturing a ceramic porous body into a mold to form a desired shape, and a drying step of drying the molded porous body to have stable pores; after pouring the slurry having the desired pore size and porosity into the mold in the above step, the mold is placed in a dryer and 40 It was dried slowly for 2 to 4 days. To prevent cracking or collapse of the porous body during drying, it must be dried slowly and uniformly as much as possible; for this purpose, it is dried with the lid covered.

[0087] (3) A sintering step for sintering the dried porous body to impart mechanical strength; to prevent cracking or collapse of the porous body due to rapid volatilization of the binder, foaming agent, and cellulose fibers during heating, the dried porous body is gradually heated from room temperature to 700 degrees at a rate of 1 degree per minute, then heated at a rate of 5 degrees per minute, maintained at the sintering temperature for 1 hour, and then slowly cooled in the furnace. Here, in the case of HA, preferably 1100 to 1300 , most preferably 1200 It is effective, and the sintering time is 1200 It is preferable to sinter for 1 to 4 hours, and more preferably, sintering for 2 hours is most effective. The bone graft material or scaffold produced by this manufacturing process is characterized by a relatively homogeneous pore structure and shape, a porosity of 65% or more, and significantly improved mechanical strength (>10 MPa).

[0089] Description of experimental examples and drawings

[0090] Figure 2 is an optical microscope diagram showing the surface changes of a porous HA body in stages during the manufacturing process and the amount of μm cellulose fibers added as an embodiment of the present invention. The top horizontal photographs in Figure 2 show the case where foaming was performed using a slurry mixed with only a binder (0.4 wt%) and a foaming agent (0.06 wt%) to HA powder without cellulose fibers, serving as a control group. When the amount of cellulose fibers in this control group was increased to 0.2, 0.4, and 0.6 wt%, the porosity increased due to the stabilization of the pores in the foamed porous body, making it possible to manufacture a porous body having pores of a desired size.

[0091] Figure 3 is an electron microscope diagram showing the changes in pore size and distribution of the cross-section of the HA porous body in stages during the manufacturing process and the amount of μm cellulose fiber added as an embodiment of the present invention. When 0.2 wt% of cellulose fiber was added to the mixture addition conditions of this comparison group, the pore size and porosity increased due to pore stabilization in the porous body at all foamed stages (wet state, dry state, sintered state), but when the amount was increased to 0.4 and 0.6 wt%, the pore stabilization actually decreased, resulting in a decrease in pore size or inconsistency.

[0092] Figure 4 is a scanning electron microscope image showing the pore structure of a cross-section of a porous body after sintering according to the amount of μm cellulose fiber added as an embodiment of the present invention. The porous body sintered in this comparison group exhibited relatively small pores and a low porosity. When 0.2 wt% of cellulose fiber was added, the pore size and porosity increased due to the stabilization of the foamed pores; however, when the amount was increased to 0.6 wt%, the stabilization of the pores decreased, resulting in the collapse of some pores.

[0094] FIG. 5 shows the change in compressive strength of a sintered porous body according to the amount of binder added to a slurry with a P / L ratio (=0.4) in which a foaming agent (0.06 wt%) was added to HA powder not of the present invention (sintering temperature 1200 This is a drawing showing the sintering time (2 hours). Referring to Fig. 5, cracks occurred during drying when the amount of CMC added to the binder was lower than 0.3%, and a decrease in compressive strength occurred when it was higher than 0.7%. Within the range of 0.3 to 0.7, a compressive strength of about 7 MPa or higher was obtained, but it was confirmed that adding 0.4 wt% is most desirable.

[0096] FIG. 6 is a diagram showing the pore formation and shape change of a dried porous body according to the amount of blowing agent added to a slurry with a constant amount of binder (0.4 wt%) and a P / L ratio (=0.4) in HA powder as an embodiment of the present invention. Referring to FIG. 6, it was preferable that the amount of blowing agent cocobetaine added was 0.01 to 0.2 parts by weight per 100 parts by weight of the binder solution. When the blowing agent content was added outside the above range, the results obtained showed that when it was less than 0.01 wt%, only some of the HA particles became hydrophobic, resulting in poor pore formation, and when it exceeded 0.2 wt%, a large amount of blowing agent that did not adhere to the HA particles existed, so it was confirmed that the formation of the porous body could not be achieved.

[0098] FIG. 7 is a diagram showing the change in pore shape of a sintered porous body (1200°C, 2 hours) according to the stirring speed when preparing a slurry with a constant amount of binder (0.4 wt%), foaming agent (0.4 wt%), and P / L ratio (=0.4) to HA powder as an embodiment of the present invention. Referring to FIG. 7, the change in pore shape was investigated by keeping the stirring time constant at 5 minutes and increasing the stirring speed (rpm). It can be confirmed that as the stirring speed is increased, the amount of air introduced increases, and the size of the generated pores increases.

[0100] Although the present invention has been described above with reference to embodiments with reference to the accompanying drawings, it is not limited thereto and should be interpreted to encompass various variations that can be obviously derived from them by those skilled in the art. The claims are intended to encompass such variations.

Claims

Claim 1 delete Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete Claim 8 A method for manufacturing a ceramic porous body, comprising: a binder aqueous solution preparation step of preparing a binder aqueous solution by mixing carboxymethylcellulose (CMC) as a binder with distilled water; a ceramic powder mixing step of mixing hydroxyapatite (HA) as a ceramic powder into the aqueous solution; a foaming agent powder mixing step of mixing cocobetaine as a foaming agent powder into the ceramic slurry; a ceramic porous body manufacturing slurry preparation step of preparing a ceramic porous body manufacturing slurry by mixing cellulose fibers into the ceramic porous body manufacturing slurry; a foaming step of forming uniform pores by stirring the ceramic porous body manufacturing slurry at 500 to 700 rpm; a molding step of pouring the ceramic porous body manufacturing slurry into a mold to form a desired shape; a drying step of drying the molded porous body to have stable pores; and a sintering step of sintering the dried porous body to impart mechanical strength. Claim 9 A method for manufacturing a ceramic porous body according to claim 8, characterized in that the drying step is carried out at room temperature.

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