JPWO2019146558A1 - Porous molded body - Google Patents

Abstract

Provided is a porous molded body made of a hydrophilic material and closely arranged with regularity regardless of the pores. The porous molded body (10) has voids inside, and a plurality of openings (12a) are formed on the surface (10S). The opening (12a) of the porous molded body (10) has voids exposed on the surface (10S). The porous molded body (10) has voids opened on the surface (10S). A plurality of spherical pores are connected inside the molded body (10), and these pores form a void.

Description

The present invention relates to a porous molded product.

As the porous molded body, a film-shaped porous molded body (hereinafter referred to as a porous film) having a honeycomb structure by regularly forming a plurality of minute pores along the film surface is known. There is. The porous film having this honeycomb structure is produced by a dew condensation method (also called a Breath Figure method). In the dew condensation method, a cast film is formed by casting a solution containing a hydrophobic material for forming a film, and after dew condensation is formed on the cast film, the solvent and water droplets are evaporated to form a film. Is a method of manufacturing. The porous film obtained by this dew condensation method is formed in a state in which a large number of extremely small pores are regularly arranged using water droplets as a template. Therefore, for example, a culture carrier (cells) for culturing cells. It is useful in the medical field such as culture medium), anti-adhesion material, or filtration filter.

Further, Patent Document 1 describes a porous film in which the diameter of the formed pores is larger than that of the porous film produced by the above-mentioned dew condensation method and is made of a hydrophilic material. The porous film of Patent Document 1 is manufactured from an emulsion. Patent Document 2 also describes a porous film produced from an emulsion and made of a hydrophilic material.

Further, Patent Document 3 describes an inverted opal structure containing cellulose. The structure of Patent Document 3 is a thin film, and is produced by impregnating a colloidal crystal obtained from silica particles having a particle size of 200 nm to 500 nm with a solution containing cellulose. Since this structure is obtained by using a colloidal crystal as a template, the diameter of the pores of the obtained structure is about the same as the diameter of the colloidal crystal.

International Publication No. 2017/104610 Japanese Unexamined Patent Publication No. 56-61437 Japanese Unexamined Patent Publication No. 2009-268836

The porous film produced by the dew condensation method is limited to hydrophobic materials because of the production method in which water droplets are used as a mold as described above. The molded body that can be formed by the dew condensation method is a thin film called a film. Further, although the methods of Patent Documents 1 to 3 can obtain a porous molded product from a hydrophilic material, the obtained porous molded product is limited to a thin material called a film. The porous film of Patent Document 2 has a high porosity (ratio of the volume occupied by the pores), but the arrangement of the pores is not orderly, and it cannot be said that there is regularity. In this respect, if the porous molded body is a three-dimensional three-dimensional object thicker than the film and the pores are closely arranged with regularity regardless of the portion, the use of the porous molded body will be expanded.

Therefore, an object of the present invention is to provide a porous molded product made of a hydrophilic material and closely arranged with regularity regardless of the pores.

In order to solve the above problems, the porous molded product of the present invention is made of a hydrophilic material and has voids that open on the surface. This void is formed by communicating with each other a plurality of spherical pores arranged in a close-packed structure.

The diameter of the pore portion is preferably in the range of 1 μm or more and 1 mm or less.

The openings are preferably arranged regularly on the surface. Further, it is preferable that the openings have the same diameter.

The close-packed structure is preferably a hexagonal close-packed structure and / or a cubic close-packed structure.

The volume fraction of the voids with respect to the entire porous molded product is preferably 74% or more.

The length between the centers of the holes in contact with each other is preferably smaller than the diameter of the holes.

The size distribution of the plurality of spherical pores is preferably 5% or less.

The hydrophilic material is preferably biocompatible. The hydrophilic material is preferably selected from collagen, polyglycolic acid, chitosan and hydroxyapatite and derivatives or mixtures of collagen, polyglycolic acid, chitosan and hydroxyapatite. Further, the hydrophilic material preferably has biodegradability.

According to the present invention, there is provided a porous molded product made of a hydrophilic material and closely arranged with regularity regardless of the pores.

It is a perspective view of the porous molded article of 1st Embodiment of this invention. It is a schematic plan view which shows a part of the surface of the porous molded article of this invention. It is a schematic cross-sectional view which shows a part of the cross section of the porous molded article of this invention. It is explanatory drawing which shows typically the structure of the hole part. It is explanatory drawing which shows typically the relationship of the hole part which touches. It is an image which image | photographed the perforated molded article in 1st Embodiment by a digital camera. It is an image taken by the optical microscope of the porous molded body in 1st Embodiment. It is an X-ray CT image of the porous molded article in the first embodiment. It is a flow figure explaining the process of manufacturing the porous molded article of this invention. It is explanatory drawing of the molding material adjustment process. It is explanatory drawing of the three-dimensional process and the continuous phase removal process. It is explanatory drawing of the curing process. It is explanatory drawing of the dispersed phase removal process and the cleaning process. It is a schematic plan view which shows a part of the surface of the porous molded article in 2nd Embodiment of this invention. It is explanatory drawing of the end face of the porous molded body in 3rd Embodiment of this invention.

[First Embodiment]
FIG. 1 shows a porous molded product (hereinafter, also referred to as a molded product) 10 which is an example of the present invention. The porous molded body 10 is formed in a cylindrical body, that is, a columnar shape having a circular cross section, and the bottom surface 10B has a diameter D10 of 10 mm and a height H10 of 10 mm. However, the shape and size are not limited to this example, and the smallest dimension among the dimensions in the three orthogonal directions may exceed 1 mm. The porous molded body 10 has a void 12 inside thereof, and a plurality of openings 12a are formed on the surface 10S. In the opening 12a, the void 12 is exposed on the surface 10S. That is, the molded body 10 has a void 12 opened on the surface 10S. In FIG. 1, only a part of a large number of openings 12a is drawn in order to avoid complication of the drawing.

As shown in FIG. 2, a plurality of spherical pores 13 are connected inside the molded body 10, and these pores 13 form a gap 12. Each pore portion 13 is a virtually partitioned conceptual space portion, and each pore portion 13 and the void 12 are defined by a hydrophilic material. That is, the molded body 10 is formed of a hydrophilic material, and in the voids 12, a plurality of spherical pores 13 communicate with each other by a communication port 12b formed in a partition wall 14 between the pores 13. It is formed by being there. The voids 12 are formed by communicating a plurality of spherical pores 13 arranged in a close-packed structure with each other. As shown in FIG. 2, the void 12 is open to the surface 10S. Reference numeral 12a is attached to the opening formed by the void 12 on the surface 10S. The voids are formed by communicating spherical pores 13 arranged in a close-packed structure with each other and opening to the surface 10S to form an opening 12a. Pore portions 13 having substantially the same size are arranged in a close-packed structure both on the surface 10S and inside the molded body 10.

For example, when the molded body 10 is viewed from a direction perpendicular to the surface 10S, a state in which six peripheral pore portions 13 are arranged at each apex of a hexagon centered on an arbitrary one pore portion 13. Each of the pores 13 is densely arranged. As a result, the molded body 10 has a honeycomb structure having a honeycomb shape. In addition, in this specification, a "honeycomb structure" means not only a two-dimensional array but also a three-dimensional space filling structure. Further, there are also a plurality of pores 13 having a honeycomb structure in the depth direction of the paper surface of FIG. 2 of the plurality of pores 13 forming the surface 10S. Therefore, as shown in FIG. 2, in the opening 12a, the partition wall 14 between the pores 13 in the depth direction of the paper surface of FIG. 2 is confirmed. Therefore, the openings 12a are regularly arranged, and the communication ports 12b communicating with the other holes 13 in contact with the holes 13 are regularly arranged in the openings 12a. Therefore, on the surface of the molded body 10, a surface having the same diameter of the opening 12a is formed, and on the molded body 10, the diameter of the opening 12a of the surface 10S is substantially the same. Since the molded body 10 is a cylindrical body, each of the side surface and the bottom surface of the molded body 10 can be said to be surfaces, but on each surface of the molded body 10, the openings 12a are regularly arranged and the diameter of the openings 12a. Is almost the same on each side. In the molded product of the present invention, the entire outer surface of the molded product can be referred to as a "surface" regardless of the shape of the molded product. Therefore, for example, even when the surface of the molded product is a curved surface, the openings 12a are regularly arranged on the surface, and the diameters of the openings 12a are substantially the same.

Although the plurality of pores 13 are spherical, they are arranged in a close-packed structure as described above, so that the true sphere is not a strict cubic shape but a slightly distorted spherical shape. Therefore, the vacant portion 13 in contact has a center-to-center distance D2 (FIG. 5) between the vacant portion 13 and another vacant portion 13 in contact with the vacant portion 13 rather than the diameter D1 of the vacant portion 13 (see FIG. 5). See) is small. As a result, the communication port 12b is formed, and the gap 12 in which the pores 13 communicate with each other is formed. Depending on the type of hydrophilic material, the pores 13 can be deformed. The ratio of the diameter D1 of the hole portion 13 to the center-to-center distance D2 can be changed depending on the manufacturing conditions. As shown in FIGS. 2 and 3, the plurality of pore portions 13 communicate with all the pore portions 13 in contact with each other, and the partition wall 14 forms the communication port 12b. Therefore, the void 12 penetrates the molded body 10. Further, as shown in FIG. 3, the molded body 10 has a cross section 10c having the same diameter of the openings 12b. In this way, since the pores 13 communicate with each other and the voids 12 penetrate, the molded body 10 can be used for various purposes such as a cell culture substrate, a light scattering filter, a sound absorbing material, and a filtration filter. Can be done.

The close-packed structure includes both a state in which the pores 13 are arranged as a hexagonal close-packed structure and a state in which the pores 13 are arranged as a cubic close-packed structure (face-centered cubic lattice structure). The region of the hexagonal close-packed structure and the region of the cubic close-packed structure may coexist. As shown in FIG. 4, as an example, in a portion of the molded body 10, the pore portions 13 are arranged in three dimensions with a hexagonal close-packed structure. That is, the spherical pores 13 are arranged two-dimensionally in the first layer I shown by the broken line, and two-dimensionally in the second layer II shown by the two-point broken line so as to overlap the first layer I. They are arranged in a three-dimensional hexagonal close-packed structure by arranging them most densely and arranging them two-dimensionally in the third layer III so as to overlap each other. In the molded body 10, the partition wall 14 and the column 10d form a gap 12 and a hole portion 13.

The size distribution of the plurality of spherical pores 13 is preferably 5% or less. Here, the size of the hole portion 13 means a sphere circumscribing the hole portion 13 and the diameter of the sphere. Further, the size distribution of the pore portions 13 refers to the ratio of the standard deviation to the average value in the sizes of all the pore portions 13 of the molded body 10. Therefore, the volume fraction of the void 12 with respect to the entire molded body 10 is about 74% because the pore portion 13 has a close-packed structure. The volume fraction of the void can be 74% or more. For example, the volume fraction of the void becomes 74% or more by setting the size of the pore portion to two types, large and small. The upper limit of the volume fraction of the void is 90% or less for the reason of maintaining the strength as a structure.

The diameter D1 of the pore portion 13 is 400 μm, but is not limited to this example, and is preferably in the range of 1 μm or more and 1 mm or less. More preferably, it is in the range of 150 μm or more and 750 μm or less, and further preferably, it is in the range of 200 μm or more and 600 μm or less. The shape and size of the molded body are not limited, but as an example, the molded body 10 of this embodiment is a cylindrical body having a bottom surface of 10 mm in diameter and a height of 10 mm, as shown in FIG. The molded product having a thickness larger than that of the film and having a thickness of 1 mm or more is regarded as a molded product having a three-dimensional structure.

The molded body 10 is made of polyacrylamide as the above-mentioned hydrophilic material. Examples of other hydrophilic materials forming the molded body 10 include various water-soluble polymers, polysaccharides (for example, cellulose or chitosan), proteins (for example, collagen or fibroin, etc.), and among these. It may be a mixture of at least two kinds of. The molded product 10 made of a hydrophilic material can be used for various purposes such as a cell culture substrate, a light scattering prevention filter, a sound absorbing material, and a filtration filter.

The hydrophilicity means that the solubility in pure water is 0.2 g / ml or more, and the hydrophobicity means that the solubility in pure water is 0.01 g / ml or less. In this embodiment, the solubility in pure water is determined by the Test No. 1 described in OECD guidelines for the Testing of Chemicals. 105: Requested by Water Solubility (OECD is the Organization for Economic Co-operation and Development). When the molding material 20 described later contains a surfactant, the obtained molded product 10 may also contain the surfactant.

As described above, the modes of the molded body 10 in which the pores 13 are regularly and densely arranged are, for example, an image taken by a digital camera as shown in FIG. 6 and an image taken by an optical microscope as shown in FIG. And, as shown in FIG. 8, it is confirmed by X-ray CT (Computed Tomography) image. FIG. 6 is an image taken from the outside of the container by immersing the molded product 10 obtained by the method described later in the water inside the container. There is a white lid on the top of the container, and FIG. 6 is an image taken with the container supported by pinching the lid with human fingers. FIG. 7 is an image of the molded product 10 immersed in water in the container as in FIG. Further, the image of FIG. 8 is an image obtained by storing the molded product 10 obtained by the method described later in water, then taking it out of water, and freeze-drying it.

As shown in FIG. 9, the molded body 10 is manufactured by having a molding material preparation step, a three-dimensionalization step, a continuous phase removing step, a curing step, a stripping step, a dispersed phase removing step, and a cleaning step. Manufactured by the method.

The molded body 10 is manufactured from the molding material 20 (see FIG. 12), and the molding material adjusting step is a step of manufacturing the molding material 20. The molding material 20 is an emulsion (emulsion, emulsion), and as shown in FIG. 10, the droplets which are the dispersed phase 21 are the oil phase, and the continuous phase 22 is the aqueous phase. The continuous phase 22 contains the raw material of the material constituting the molded product 10 as a curable compound. As described above, the curable compound of this example becomes a hydrophilic material after curing. The curable compound in this example is acrylamide. The continuous phase 22 may contain a solvent of a curable compound. The droplets that are the dispersed phase 21 function as a template for the pores 13 in the molded product 10, and include polydimethylsiloxane in this example.

The continuous phase 22 contains a curable compound as described above. In this example, the continuous phase 22 contains a curable compound and water as a solvent for the curable compound, but the curable compound is a liquid incompatible with the dispersed phase 21 which is a hydrophobic liquid. In some cases, the continuous phase 22 may not contain water. The fact that it is incompatible with the hydrophobic liquid means that the solubility in the hydrophobic liquid is 0.01 g / ml or less. Examples of the curable compound when the continuous phase 22 is an aqueous phase include a compound in which a hydrophilic monomer is modified with a curable functional group, and a handbook for organic synthesis (for example, a handbook for organic synthesis experiments (Synthetic Organic Chemistry Association)). )), Etc., can be obtained by modifying a functional group having energy ray curability (including photocurability) and / or thermosetting.

In this example, the curable compound is an ultraviolet curable compound that is cured by irradiation with ultraviolet rays, but the curable compound is not limited to this. As the curable compound, an energy ray-curable compound that is cured by irradiation with energy rays, a thermosetting compound that is cured by heating, and an ion-curable compound that is cured by an ionic reaction can be used. An example of an energy ray-curable compound that is cured by irradiation with energy rays is a photocurable compound that is cured by irradiation with light such as ultraviolet rays. Examples of the ion-curable compound include a system in which sodium alginate is reacted with a multivalent cation such as calcium (Ca) ion.

The curable compound is preferably biocompatible. As a result, a molded body 10 used as a cell culture substrate, a hemostatic material, an adhesion preventing material, and / or a wound covering material can be obtained. The biocompatibility means a property that does not have a harmful effect on the living body such as toxicity to the living body when it is placed in the living body (including the inside of the digestive tract) or when it is attached to the outside of the living body.

The molding material 20 may contain a cross-linking agent for curing the curable compound in the continuous phase 22, and in this example as well, N, N'-methylenebisacrylamide (manufactured by Tokyo Chemical Industry Co., Ltd.) is used as the cross-linking agent. Contains. Further, the continuous phase 22 may contain an initiator for initiating the curing of the curable compound, and in this example as well, IRUGACURE (registered trademark) 2959 (manufactured by BASF SE) is contained as an initiator. ..

The droplets of the dispersed phase 21 are preferably flexible and deformable, and this is also the case in this example. The diameter of the droplets of the dispersed phase 21 is preferably in the range of 20 μm or more and 1 mm or less. When it is 20 μm or more, coalescence of the droplets is less likely to occur as compared with the case where it is less than 20 μm, and the dispersed phase 51 of the deformable droplet is more reliably maintained. When it is 1 mm or less, the shape of the droplet can be more reliably held in a spherical shape in a left state as compared with the case where it is larger than 1 mm. The diameter of the dispersed phase 51 is more preferably in the range of 0.1 mm or more and 1 mm or less, and further preferably in the range of 0.2 mm or more and 0.6 mm or less.

It is preferable that there is a difference in specific gravity between the dispersed phase 21 and the continuous layer 22. When the specific gravity of the dispersed phase 21 is Y1 and the specific gravity of the continuous phase 22 is Y2, the specific gravity difference obtained by Y1-Y2 is preferably 0.001 or more, and is 0.080 in this example. When the specific gravity difference is 0.001 or more, it becomes easier for the dispersed phase 21 to be unevenly distributed in the vertical direction, that is, unevenly distributed downward in the molding material 20 as compared with the case where it is less than 0.001. In this way, since the dispersed phase 21 and the continuous phase 22 are more easily separated in the molding material 20 in the vertical direction, the molding material 20 is held in a state where the dispersed phases 21 are more reliably in contact with each other in the three-dimensional step. can do. Further, in the case of manufacturing the molded body 10, since the floating of the dispersed phase 21 is suppressed in the three-dimensional step and the curing step, the molded body 10 can be easily manufactured.

The difference in specific gravity is more preferably in the range of 0.001 or more and 0.200 or less. When it is 0.200 or less, the coalescence of the dispersed phases 21 which are droplets is suppressed more reliably and / or for a longer period of time than when it exceeds 0.200. For example, if the difference in specific gravity is too large, the dispersed phase 21 in a state of being unevenly distributed downward (precipitated state) may be crushed and the stable state as a droplet may be disturbed. The specific gravity difference is more preferably in the range of 0.030 or more and 0.150 or less, and particularly preferably in the range of 0.050 or more and 0.100 or less.

The specific gravity Y1 and the specific gravity Y2 are obtained on the basis of setting the specific gravity of water at 25 ° C. to 1. In the present embodiment, more specifically, the specific gravity of the first liquid 35 described later is Y1, the specific gravity of the second liquid 36 described later is Y2, and the specific gravity of the first liquid 35 is a volume V at 25 ° C. The first liquid 35 and the second liquid 36 are prepared respectively, and the mass W of each of the prepared first liquid 35 and the second liquid 36 is measured 10 times, and each measured value is calculated by the formula of W / V. Then, the average value of the calculated 10 calculated values is obtained as the specific gravities Y1 and Y2.

The molding material 20 has a volume ratio of the dispersed phase 21 in the range of 0.5 or more and 0.9 or less, and contains the dispersed phase 21 in such a high volume ratio. The volume ratio of the dispersed phase 21 is obtained by X1 / (X1 + X2) when the volume of the dispersed phase 21 is X1 and the volume of the continuous phase 22 is X2. Since the volume ratio of the dispersed phase 21 is 0.5 or more, the droplets of the dispersed phase 21 are arranged in contact with each other as compared with the case where the volume ratio is less than 0.5, and the arrangement is more regular. Become. When the volume ratio of the dispersed phase 21 is 0.9 or less, the coalescence of the dispersed phases 21 can be more reliably suppressed as compared with the case where the volume ratio exceeds 0.9. Therefore, it is easier to manufacture the molded body 10 in which the pores 13 having uniform sizes are regularly arranged.

The volume ratio of the dispersed phase 21 is more preferably 0.6 or more and 0.85 or less, and further preferably 0.7 or more and 0.8 or less. As a method of obtaining the volume ratio of the dispersed phase 21, for example, there is a method of obtaining from an image observed with a microscope. Specifically, the average size and the number density of the droplets of the dispersed phase 21 can be obtained from the observation image of the molding material 20, and the volume ratio of the dispersed phase 21 can be calculated from these average size and the number density. Further, when the volume ratio of the dispersed phase 21 of the molding material 20 and the volume ratio of the pores 13 of the obtained molded body 10 are the same, the average size and number of the pores 13 from the observation image of the molded body 10 By determining the density and the volume ratio of the pores 13 from these, this may be regarded as the volume ratio of the dispersed phase 21 in the molding material 20.

The molding material 20 may contain a surfactant, and in this example as well, it contains polyvinyl alcohol as a surfactant. Other examples of the surfactant include a surfactant having an HLB value of 11 or more and 16 or less, such as Adecator (registered trademark) LA and NIKKOL Hexaglin 1-M (hexaglyceryl monomyristate).

The molding material 20 preferably contains a specific gravity adjusting agent. In this example, a compound that increases the specific gravity of the dispersed phase 21 is used as the specific gravity adjusting agent, but the specific gravity adjusting agent adjusts (increases or decreases) the specific gravity of at least one of the dispersed phase 21 and the continuous phase 22. It should be. In this example, bromobenzene, which has a higher specific gravity than polydimethylsiloxane, is used as the specific gravity adjusting agent in order to increase the specific gravity of the dispersed phase 21. However, when the dispersed phase 21 is an oil phase, the specific gravity adjusting agent that increases the specific gravity of the dispersed phase 21 is not limited to this, and exists in a dissolved state in the dispersed phase 21 and is a component of the dispersed phase 21. Any compound having a higher specific gravity than (polydimethylsiloxane in this example) may be used. For example, chloroform and / or carbon tetrachloride can be used.

The specific gravity adjusting agent is preferably contained in the dispersed phase 21 as in this example. Further, the specific gravity adjusting agent is preferably contained in a mass ratio within the range of 1% or more and 30% or less with respect to the dispersed phase 21. This mass ratio is (M2 / M1) × when the mass of the dispersed phase 21 (including the mass of the specific gravity adjusting agent) is M1 and the mass of the specific gravity adjusting agent contained in the dispersed phase 21 is M2. It is a percentage calculated by 100.

The molding material 20 can be formed by the base generating section 25 shown in FIG. 10 and the adjusting section 26 shown in FIG. The base generation unit 25 produces an emulsion base 37 (see FIG. 11) in which the volume ratio of the dispersed phase 21 is smaller than that of the molding material 20. The base generating unit 25 includes a first pipe 31 and a second pipe 32 having a circular cross section. The first tube 31 supplies the first liquid 35 that becomes the dispersed phase 21. The second tube 32 sends the second liquid 36 which becomes the continuous phase 22. The first pipe 31 is fitted to the side surface of the second pipe 32 so that one end side is arranged in the hollow portion of the second pipe 32. The opening 31a on one end side of the first pipe 31 is arranged so as to face the flow direction of the second liquid 36 flowing in one direction through the hollow portion of the second pipe 32 (downstream side in the flow direction of the second liquid 32). ing. As a result, the first liquid 35 is discharged as droplets from the opening 31a in the flow direction of the second liquid 36. Further, the opening 31a is located substantially in the center of the circular cross section of the second pipe 32.

In the present embodiment, the first pipe 31 having an outer diameter within the range of 0.8 mm or more and 3.0 mm or less, the inner diameter being larger than the outer diameter of the first pipe 31, and the outer diameter being approximately 1. A second pipe 32 within a range of 4 mm or more and 4.0 mm or less is used. However, the first pipe 31 and the second pipe 32 are not limited to this example.

When the liquid feed flow rate of the first liquid 35 is V1 and the liquid feed flow rate of the second liquid 36 is V2, in the present embodiment, for example, V1 is set to 3 ml / hr and V2 is set to 4.5 ml / hr. By supplying the first liquid 35 and the second liquid 36 under the above conditions, the dispersed phase 21 is generated, whereby the emulsion base 37 having a uniform diameter of the dispersed phase 21 is produced. The base generating unit 25 is particularly effective when the diameter of the dispersed phase 21 is relatively large, within the range of 300 μm or more and 1 mm or less.

In this example, the specific gravity adjusting agent is contained in the first liquid 35. As a result, the dispersed phase 21 containing the specific gravity adjusting agent is produced. Further, the cross-linking agent, the initiator and the surfactant are contained in the second liquid 36. As a result, the continuous phase 22 containing the cross-linking agent and the initiator is generated, and the droplets of the dispersed phase 21 are maintained in a stable state in the continuous phase 22.

The obtained emulsion base 37 is sent to the container 38 of the adjusting unit 26 shown in FIG. As shown in FIG. 11, the adjusting unit 26 includes a container 38 containing the emulsion base 37 and a pump 39. The pump 39 sucks the second liquid 36 from the emulsion base 37 in the container 38, thereby increasing the volume ratio of the dispersed phase 21 in the emulsion base 37. As a result, the molding material 20 is obtained.

As shown in FIG. 12, the three-dimensional step is a step of accommodating the molding material 20 in a container 41 having a size including the entire molded body 10. In this example, a container 41 having an inner wall which is the outer shape (shape and size) of the molded body 10 is used, and the container 41 is made of glass through which light from the light source 40 is transmitted. Since the molded product 10 after curing is formed of a hydrophilic material, a container 41 made of a hydrophobic material may be used from the viewpoint of easy separation between the container 41 and the molded product 10. If the dispersed phases 21 are in contact with each other at the time of accommodation, they may be immediately subjected to the curing step. Further, if a region where the dispersed phases 21 are separated from each other is recognized in the molding material 20 at the time of accommodating, a process such as standing still or gently vibrating and / or shaking until the dispersed phases 21 are in contact with each other is observed. It is advisable to perform the curing process after performing.

In the continuous layer removing step, after the dispersed phases 21 are in contact with each other, when the arrangement of the dispersed phases 21 is almost nonexistent in the upper part of the container 41, that is, when only the substantially continuous phase 22 is present, this continuous layer removal step is performed. This is a step of removing the phase 22. A pump 39 can be used to remove the continuous phase 22.

As shown in FIG. 12, the curing step after the continuous layer removing step is a step of curing the curable compound contained in the continuous phase 22 of the molding material 20. Since acrylamide, which is the curable compound of this example, is a photocurable compound, a light source 40 is used in the curing step, for example, as shown in FIG. In the curing step, the container 41 is placed under the above-mentioned light source 40, and the curable compound in the molding material 20 is cured. Since the molding material 20 may be irradiated with light, the positional relationship between the light source 40 and the container 41 is not particularly limited. Further, a plurality of light sources 40 may be arranged around the container 41, and light may be emitted toward the container 41 from different directions. The light source 40 is arranged above the glass container 41 containing the molding material 20. In this state, by emitting light for curing the curable compound from the light source 40, the molding material 20 is irradiated with light through the transparent container 41, and the curing compound is cured by this irradiation, and the molding material 20 is cured. The solidified body 42 is obtained by solidifying the continuous phase. The light source 40 in this example irradiates ultraviolet rays as light.

The curing apparatus for the curing step is not limited to the light source 40, and is determined according to the curing method. For example, when the curable compound is a thermosetting compound that is cured by heating, various heating devices such as a heating oven (heating constant temperature bath) or an infrared heater are used in the curing step. When the curable compound is an ionic curable compound that is cured by an ionic reaction, for example, a liquid tank containing an ionic solution is used as a curing device. As a specific method, the ion solution of this liquid tank (for example, a liquid containing calcium ions) is placed in a container 41 containing the molding material 20 little by little so as not to disturb the arrangement of the dispersed phase 21 of the molding material 20. By injecting, an ion curable compound (eg, sodium alginate) is cured.

The stripping step is a step of separating the solidified body 42 obtained by this curing from the container 41. Any method can be adopted for the separation, which may be performed by heat or may be physically peeled off. When it is performed by heat, the container 41 can be alternately immersed in cold water and hot water. In this example, the solidified body 42 is stripped from the container 41 by immersing the container 41 containing the solidified body 42 in the water of a bathtub containing water at 25 ° C. Further, the container 41 containing the solidified body 42 may be alternately and repeatedly immersed in different first bathtubs (not shown) and second bathtubs (not shown). In this case, the temperature difference between the first bathtub and the second bathtub is sufficient. Further, in the case of physically peeling off, the solidified body 42 can be separated by partially scraping the surface. The solidified body 42 exfoliated from the container is subjected to a dispersion phase removing step, and the dispersed phase 21 is removed to obtain a molded body 10.

As shown in FIG. 13, the dispersed phase removing step is a step of removing the dispersed phase 21 from the solidified body 42 obtained by the stripping step. In this example, the liquid 45 is soluble in the dispersed phase 21 in the solidified body 42 and insoluble in the continuous phase (the product produced by curing the curable compound) in the solidified body 42. The dispersed phase 21 is removed from the solidified body 42 by immersing the solidified body 42. The liquid used in this example is acetone, but is not limited to acetone. The liquid 45 used is not limited to the meaning that the insolubility in the continuous phase in the solidified body 42 is completely insoluble, and the solubility of the continuous phase in the liquid to be used after curing is 0.01 g / ml or less. It may be considered insoluble. However, as described above, when the solvent of the curable compound remains in the continuous phase, the product produced by curing the curable compound even if the solubility of the continuous phase is larger than 0.01 g / ml. If the solubility is 0.01 g / ml or less, it may be regarded as insoluble. Since the dispersed phases 21 are in contact with each other in the solidified body 42, the dispersed phase 21 is easily removed, and the dispersed phase 21 is also removed by a method other than drying such as immersion in this example. Therefore, there is a degree of freedom in selecting the material to be used as the dispersed phase 21. As described above, since the degree of freedom of the material used as the dispersed phase 21 is high, the degree of freedom in selecting the material of the continuous phase 22 to be used together with the dispersed phase 21 is also high, and as a result, the molded product 10 of various materials can be obtained.

In the washing step, after the dispersed phase removing step, the molded body 10 is washed by immersing the molded body 10 in water and / or a solvent. When the molded product 10 is used for an application that dislikes impurities, it is preferable to perform a cleaning step.

The operation of this embodiment will be described. The molded body 10 is obtained from the molding material 20 as described above. The molding material 20 includes a dispersed phase 21 and a continuous phase 22, and the droplets, which are the freely deformable dispersed phase 21, function as a template for the pores in the molded body 10. Since the dispersed phase 21 is included in the above-mentioned volume ratio, the droplets of the dispersed phase 21 are arranged in contact with each other, and the arrangement becomes more regular. Further, since the dispersed phases 21 are arranged in contact with each other, the dispersed phases are easily removed in the dispersed phase removing step, and as a result, a molded body 10 in which the pores 13 communicate with each other can be obtained. In this way, the continuous phase 22 and the dispersed phase 21 are separated from each other, and the dispersed phase 21 is flexible and deformable. Therefore, due to gravity, the molding material 20 is put into a container which is a mold when the molded body 10 is manufactured. The dispersed phase 21 is self-organized and arranged in a three-dimensional close-packed structure just by inserting. Even when a molding material having a relatively small difference in specific gravity between the continuous phase 22 and the dispersed phase 21 is used, the dispersed phase 21 is three-dimensionally self-organized by putting the molding material 20 in a container and leaving it to stand. Arrange in a close-packed structure. Further, since the droplets of the dispersed phase 21 are deformable, in the three-dimensional step, the dispersed phase 21 contained in the dense state forms a regular arrangement more reliably, and a gap is formed downward due to gravity. If you move there. Therefore, the molded body 10 is arranged in a state in which the dispersed phases 21 are more reliably distributed in a regular arrangement and the dispersed phases 21 are more reliably in contact with each other. Further, the dispersed phase 22 can be rearranged even if it is self-organized and has a highly regular sequence. Further, since the shape of the porous molded product follows the shape of the container, various shapes of the porous molded product can be easily obtained.

The molded body 10 has a void 12 that opens on the surface, and the void 12 is formed by communicating a plurality of spherical pores 13 arranged in a close-packed structure with each other. Further, the molded body 10 is a molded body 10 made of a hydrophilic material, in which the pores 13 in which the dispersed phase 21 serves as a mold are regularly and densely arranged regardless of the surface or the inside. is there. It should be noted that "any part" does not mean strictness, and most parts of the molded body 10 are highly regularly arranged, and some parts such as corners and edges are arranged. It means that there may be a disordered part. In the manufacturing process of the molded body 10, the dispersed phase 21 has a close-packed structure and is highly regularly arranged along the container 10 by a step of removing the continuous phase 22 or the like. The openings 12a on the surface of 13 are also highly regularly arranged in a close-packed structure. Similarly, inside the molded body 10, since the dispersed phase 21 has a close-packed structure and is highly regularly arranged, the pores 13 are also highly regularly arranged in the close-packed structure. Further, when a container having a curved surface is used, the surface of the molded body has a curved surface similar to that of the container, and the openings are highly regular along the curved surface, for example, like a dent of a golf ball. It is possible to obtain a molded body arranged in a uniform manner. Therefore, in the molded body 10, the pores having a uniform size are arranged highly regularly in a close-packed structure, and these open to the communicating surface, and the openings are also arranged highly regularly. It is suitable for applications in which it is preferable to have uniform pores, applications in which it is preferable to densely fill the pores with a substance or the like, and applications in which a large surface area is preferable. Further, since the same raw material can be used as a light molded product, it is also suitable for applications in which light weight is preferable. Further, by adjusting the diameter of the pore portion 13 to the diameter of the dispersed phase 21, a porous molded body having a wide range of diameters of 1 μm or more and 1 mm or less or a molded body having a porous surface can be easily obtained. Therefore, the size distribution of the pores is small, the size of the pores can be specified, and a molded product adjusted to a specific porosity can be easily obtained. Therefore, it is used for sieving, filters, etc. It is also suitable for.

Since the close-packed structure is a hexagonal close-packed structure and / or a cubic close-packed structure, and the pores 13 are molded bodies 10 that are densely arranged along the packed structure with regularity, the holes are formed. It is suitable for applications in which it is preferable that 13 are arranged regularly. Further, since the volume fraction of the void 12 with respect to the entire porous molded body can be as high as 74% or more, it is suitable for applications in which a large void 12 is preferable. Further, since the distance D2 between the centers of the vacant holes 13 in contact is smaller than the diameter D1 of the vacant holes 13, the vacant holes 13 communicate with each other more reliably. Therefore, it is suitable for applications in which it is preferable that the void 12 of the molded body 10 penetrates. Further, since the size distribution of the plurality of spherical pores 13 is as small as 5% or less, it is preferable that the sizes of the pores 13 are the same and the sizes of the pores 13 are the same. It is suitable. Further, since the hydrophilic material has biocompatibility, it is suitable when the molded product 10 is used for biological-related applications. Further, since the hydrophilic material is selected from collagen, polyglycolic acid, chitosan and hydroxyapatite and derivatives or mixtures of collagen, polyglycolic acid, chitosan and hydroxyapatite, for example, the molded product 10 is used for the human body. Suitable for applications. Further, since the hydrophilic material has biodegradability, it is suitable because it has a small burden on the environment.

Further, when there is a difference in specific gravity between the dispersed phase 21 and the continuous phase 22, the contact area between the dispersed phases 21 is further increased due to the difference in specific gravity. Therefore, a larger communication port 12b is formed in the obtained molded body 10. It is effective that the communication port 12b is formed larger in this way, for example, when the molded product 10 is used as a cell culture base material, an interaction route between the cultured cells is secured.

[Second Embodiment]
As shown in FIG. 14, the molded body 50 of the second embodiment has a structure in which pore portions 51 different from the pore portions 13 are regularly embedded in the gaps of the hexagonal close-packed structure of the pore portions 13. ing. Therefore, on the surface 50a of the molded body 50, the openings 13a of the pores 13 and the openings 51a of the holes 51 are regularly arranged. The plurality of openings 13a have the same diameter, and the plurality of openings 51a have the same diameter. Further, the hole portion 13 and the hole portion 51 communicate with each other at a contact portion. The gap 52 composed of the hole portion 13 and the hole portion 51 penetrates the molded body 50.

The molded body 50 is the same as that of the first embodiment except that two types of dispersed phases having different droplet diameters are used as the dispersed phase. An emulsion base material containing a dispersed phase 1 using a dispersed phase having a large droplet diameter (hereinafter referred to as dispersed phase 1) and a dispersed phase having a smaller droplet diameter (hereinafter referred to as dispersed phase 2). And the emulsion base material containing the dispersed phase 2 are separately produced, and then both are mixed in the preparation unit 26. Other steps are the same as those in the first embodiment.

As described above, by using dispersed phases having different diameters of droplets, a molded product having a higher porosity can be obtained. Therefore, it is suitable for applications in which it is preferable to fill the pores with a substance or the like more precisely, and applications in which a larger surface area is preferable. Further, by variously adjusting the dispersed phases having different diameters of the droplets, the size of the pores can be made into a plurality of sizes in one molded body, and in some cases, the positions thereof can be adjusted. It is possible. For example, a dispersed phase having a large droplet diameter is placed at the bottom of the container, a dispersed phase having a slightly smaller droplet diameter is placed in the middle of the container, and a dispersed phase having a smaller droplet diameter is placed. By arranging it in the upper part of the container, it is possible to obtain a porous molded body in which the arrangement of the pores is changed stepwise. Therefore, in the same molded product, it is suitable for applications where it is preferable to have different functions for each part of the region. By adjusting the continuous phase and the dispersed phase in this way, a molded product having controlled pores can be easily obtained.

[Third Embodiment]
As shown in FIG. 15, the molded body 60 of the third embodiment has a curved surface 60a on a part of the molded body 60. In FIG. 12, one layer of the pore portion 61 forming the surface 60a is shown, and the others are omitted. Even on the surface 60a, the diameter D3 of the opening 62 is substantially the same.

The molded body 60 is manufactured in the same manner as in the first embodiment except that a container having a curved surface is used. Since the dispersed phase 21 is deformable and the dispersed phases are arranged following the curved surface, as shown in FIG. 15, the obtained molded body 60 has the surface of the opening 62 having the diameter D3 even on the curved surface. It is almost the same in all the openings 62 that open to.

As described above, regardless of the shape of the molded body, by having openings having substantially the same diameter arranged regularly on the surface, it is possible to obtain a surface shape suitable for applications such as a cell culture substrate and a sieve.

10 Molded body 10c Cross section 10d Pillar 10B Bottom surface 10S Surface 12 Void 12a Opening 12b Communication port 13 Pore 14 Partition 20 Molding material 21 Dispersed phase 22 Continuous phase 25 Base material generating part 26 Adjusting part 31 First pipe 31a Opening 32 2 tubes 35 1st liquid 36 2nd liquid 37 Emulsion base 38 Container 39 Pump 40 Light source 41 Container 42 Solidified body 45 Liquid 50 Molded body 51 Pore part 60 Molded body 60a Surface D1 Pore part 13 diameter D2 Pore part Distance between the centers of the pores 13 in contact with 13 D3 Diameter of the opening 62 D10 Diameter H10 Height I Close-packed structure of a plurality of holes 13 First layer II Close-packed structure of a plurality of holes 13 Layer III Close-packed structure of multiple pores 13 Third layer

Claims (11)

A porous molded body formed of a hydrophilic material and having voids that open on the surface, and the voids are formed by communicating a plurality of spherical pores arranged in a close-packed structure with each other. The porous molded product according to claim 1, wherein the diameter of the pore portion is within the range of 1 μm or more and 1 mm or less. The porous molded product according to claim 1 or 2, wherein the openings are regularly arranged on the surface. The porous molded product according to claim 3, wherein the openings have the same diameter. The porous molded product according to any one of claims 1 to 4, wherein the close-packed structure is a hexagonal close-packed structure and / or a cubic close-packed structure. The porous molded product according to any one of claims 1 to 5, wherein the volume fraction of the voids with respect to the entire porous molded product is 74% or more. The porous molded product according to any one of claims 1 to 6, wherein the distance between the centers of the pores in contact with each other is smaller than the diameter of the pores. The porous molded product according to any one of claims 1 to 7, wherein the size distribution of the plurality of pores is 5% or less. The porous molded product according to any one of claims 1 to 8, wherein the hydrophilic material has biocompatibility. The porous molded body according to claim 8, wherein the hydrophilic material is selected from the group consisting of collagen, polyglycolic acid, chitosan and hydroxyapatite and derivatives or mixtures of collagen, polyglycolic acid, chitosan and hydroxyapatite. The porous molded product according to any one of claims 1 to 10, wherein the hydrophilic material has biodegradability.

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