JP7739769B2 - Organic-inorganic composite hydrogel precursor liquid, hydrogel modeled object, and method for manufacturing hydrogel modeled object - Google Patents

Description

The present invention relates to an organic-inorganic composite hydrogel precursor liquid, an organic-inorganic composite hydrogel, a hydrogel modeled object, and a method for manufacturing a hydrogel modeled object.

In recent years, advances in the development of medical devices have led to a shift away from traditional medical treatments that involve large incisions and removal to minimally invasive treatments that place less strain on patients, such as those using catheters, endoscopes, or robotic assistance. Surgical operations using these medical devices require highly advanced techniques and expertise, and the importance of surgical training using appropriate medical organ models is recognized from the perspective of preventing medical accidents. Furthermore, for difficult surgeries with few actual cases, if medical organ models that reproduce the details of the target area can be created in advance, it will be possible to perform detailed preoperative simulations.

Examples of such medical organ models include acrylic resin models or urethane resin models made with a three-dimensional (3D) printer, or silicone resin models made by a casting method using a mold. However, the resin medical organ models described above have the problem that they cannot be used for actual procedures such as suturing and incision using an electric energy device such as an electric scalpel because the resin is hard.
Furthermore, although hydrogels derived from natural foods such as agar and konjac can be cut with an electric scalpel, they are difficult to mold into any desired three-dimensional shape, and because they have very low strength, the sensation of cutting with an electric scalpel and the suturing operation cannot be accurately reproduced.

To solve these problems, a hydrogel modeling object containing, for example, an inorganic mineral, a phosphonic acid compound, and a polymer has been proposed (see, for example, Patent Document 1).

The present invention aims to provide an organic-inorganic composite hydrogel precursor liquid that has excellent compressive stress and breaking limit, and can be used to create hydrogel-modeled objects that can be sutured or cut using electrical energy devices such as electric scalpels.

The organic-inorganic composite hydrogel precursor liquid of the present invention, which serves as a means for solving the above problems, contains a metal oxide, a monomer, a salt, a chelating agent, and water.

The present invention provides an organic-inorganic composite hydrogel precursor liquid that has excellent compressive stress and breaking limit, and can be used to create hydrogel-modeled objects that can be sutured or cut using electrical energy devices such as electric scalpels.

FIG. 1 is a schematic diagram illustrating an example of a three-dimensional printer for producing a hydrogel modeled object. FIG. 2 is a schematic diagram showing an example of a hydrogel model produced using a three-dimensional printer being peeled off from a support material.

(Organic-inorganic composite hydrogel precursor liquid)
The organic-inorganic composite hydrogel liquid precursor of the present invention contains a metal oxide, a monomer, a salt, a chelating agent, and water, and may further contain other components as required.

Commonly used acrylic resin models or urethane resin models, as well as silicone resin models made by casting using a mold, have the problem of lacking electrical conductivity and being unable to be cut with energy devices such as electric scalpels. Furthermore, hydrogel objects made using a hydrogel precursor liquid containing monomers, water, minerals, and phosphonic acid have low electrical conductivity, and carbonized materials and other materials tend to adhere during cutting with energy devices such as electric scalpels, resulting in poor cuttability.

In the present invention, by using an organic-inorganic composite hydrogel precursor liquid containing a metal oxide, a monomer, a salt, a chelating agent, and water, it is possible to fabricate a hydrogel-modeled object that has excellent compressive stress and breaking limit and can be sutured or cut using an electrical energy device such as an electric scalpel. Furthermore, because the organic-inorganic composite hydrogel precursor liquid of the present invention can be prepared to have a low viscosity, it can be suitably used as a modeling liquid for various hydrogel-modeled objects.

<Monomer>
The monomer is preferably a polymerizable monomer. Examples of the polymerizable monomer include monofunctional monomers and polyfunctional monomers having two or more functional groups. The monomers contained in the hydrogel 3D modeling composition of the present invention may be used alone or in combination of two or more types.

- Monofunctional monomer -
Examples of monofunctional monomers include (meth)acrylamide derivatives such as acrylamide, methacrylamide, N-substituted acrylamide derivatives, N,N-disubstituted acrylamide derivatives, N-substituted methacrylamide derivatives, and N,N-disubstituted methacrylamide derivatives, as well as other monofunctional monomers. These may be used alone or in combination of two or more.
Examples of (meth)acrylamide derivatives include N,N-dimethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-methylol(meth)acrylamide, (meth)acryloylmorpholine, and methylenebis(meth)acrylamide. These may be used alone or in combination of two or more. Among these, N,N-dimethylacrylamide and methylenebisacrylamide are preferred.

Other monofunctional monomers include, for example, acrylate, alkyl acrylate, methacrylate, and alkyl methacrylate.
Examples of the acrylate include hydroxyethyl acrylate, hydroxypropyl acrylate, dimethylaminoethyl acrylate, dimethylaminopropyl acrylate, and alkyl acrylate.
Examples of alkyl acrylates include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and lauryl acrylate.
Examples of methacrylates include hydroxyethyl methacrylate, hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, and alkyl methacrylates.
Examples of alkyl methacrylates include methyl methacrylate, ethyl methacrylate, butyl methacrylate, lauryl methacrylate, stearyl methacrylate, and glycidyl methacrylate.
Further, other monofunctional monomers include, for example, 2-ethylhexyl (meth)acrylate (EHA), 2-hydroxyethyl (meth)acrylate (HEA), 2-hydroxypropyl (meth)acrylate (HPA), caprolactone-modified tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, lauryl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isodecyl (meth)acrylate, isooctyl (meth)acrylate, tridecyl (meth)acrylate, caprolactone (meth)acrylate, ethoxylated nonylphenol (meth)acrylate, etc. These may be used alone or in combination of two or more.

- Polyfunctional Monomer -
The polyfunctional monomer may be a difunctional monomer or a trifunctional or higher functional monomer.
Examples of bifunctional monomers include tripropylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol hydroxypivalic acid ester di(meth)acrylate (MANDA), hydroxypivalic acid neopentyl glycol ester di(meth)acrylate (HPNDA), 1,3-butanediol di(meth)acrylate (BGDA), 1,4-butanediol di(meth)acrylate (BUDA), and 1,6-hexanediol di(meth)acrylate. Examples of suitable di(meth)acrylates include diethylene glycol di(meth)acrylate (HDDA), 1,9-nonanediol di(meth)acrylate, diethylene glycol di(meth)acrylate (DEGDA), neopentyl glycol di(meth)acrylate (NPGDA), tripropylene glycol di(meth)acrylate (TPGDA), caprolactone-modified hydroxypivalic acid neopentyl glycol ester di(meth)acrylate, propoxylated dipentyl glycol di(meth)acrylate, ethoxy-modified bisphenol A di(meth)acrylate, polyethylene glycol 200 di(meth)acrylate, and polyethylene glycol 400 di(meth)acrylate. These may be used alone or in combination of two or more.

Examples of trifunctional or higher functional monomers include trimethylolpropane tri(meth)acrylate (TMPTA), pentaerythritol tri(meth)acrylate (PETA), dipentaerythritol hexa(meth)acrylate (DPHA), triallyl isocyanate, (meth)acrylate of ε-caprolactone-modified dipentaerythritol, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, propoxylated glyceryl tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol hydroxypenta(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, and penta(meth)acrylate esters. These may be used alone or in combination of two or more.

The content of the monomer is preferably 0.5% by mass to 50% by mass, more preferably 20% by mass to 40% by mass, based on the total amount of the organic-inorganic composite hydrogel precursor liquid. By setting the content to 5% by mass to 50% by mass, the dispersion stability of the mineral in the hydrogel 3D modeling composition is improved.
The monomer is preferably water-soluble. Water-soluble means that, for example, when 100 g of water at 30° C. and 1 g of the monomer are mixed and stirred, 90 mass % or more of the monomer is dissolved.
The monomer is preferably a compound having a photopolymerizable functional group. In the present invention, the term "polymerizable functional group" refers to a functional group that undergoes a polymerization reaction upon irradiation with active energy rays or the addition of heat, and the term "photopolymerizable functional group" particularly refers to a functional group that undergoes a polymerization reaction upon irradiation with active energy rays. Examples of the photopolymerizable functional group include, but are not limited to, groups having an ethylenically unsaturated bond such as a (meth)acryloyl group, a vinyl group, or an allyl group, and cyclic ether groups such as an epoxy group. Specific examples of compounds containing a group having an ethylenically unsaturated bond include compounds having a (meth)acrylamide group, (meth)acrylate compounds, compounds having a (meth)acryloyl group, compounds having a vinyl group, and compounds having an allyl group.

<Metal oxides>
The hydrogel liquid precursor may contain a water-dispersible metal oxide, which allows for the production of a hydrogel modeled object with excellent compressive stress and rupture limit, and mechanical properties closer to those of a real organ.
The water-dispersible metal oxide is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include metal oxide fine particles and layered minerals.
Examples of metal oxide fine particles include metal oxide fine particles such as SiO ₂ , TiO ₂ , ZnO, ZrO ₂ , CeO ₂ , and Co(OH) ₂ ; and composite metal oxide fine particles such as SiO ₂ —TiO ₂ , ZrO ₂ —CeO ₂ , Fe/MnO _x , Ni/MnO _x , Co/MnO _x , and Cu/NiO _x .
The volume average particle size of the metal oxide fine particles is preferably 1 nm or more and 1,000 nm or less, and more preferably 10 nm or more and 500 nm or less.

The layered mineral is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include water-swellable layered clay minerals.
Examples of water-swellable layered clay minerals include water-swellable smectite, water-swellable mica, etc. More specifically, water-swellable hectorite, water-swellable montmorillonite, water-swellable saponite, water-swellable synthetic mica, etc., which contain sodium as an interlayer ion.
The water swelling property means that water molecules are inserted between the layers of the layered mineral and the mineral is dispersed in water.
As the water-swellable layered clay mineral, the above-mentioned examples may be used alone or in combination of two or more kinds, and may be suitably synthesized or may be a commercially available product.
Examples of commercially available products include synthetic hectorite (Laponite XLG, manufactured by RockWood), synthetic hectorite (Laponite RD, manufactured by RockWood), SWN (manufactured by Coop Chemical Ltd.), and fluorinated hectorite SWF (manufactured by Coop Chemical Ltd.). Of these, synthetic hectorite is preferred.

The content of the metal oxide is preferably 10% by mass or less, more preferably 1% by mass to 10% by mass, and even more preferably 1% by mass to 5% by mass, based on the total amount of the organic-inorganic composite hydrogel precursor liquid.
When the metal oxide content is 10% by mass or less, it is possible to form a hydrogel-modeled object that has excellent compressive stress and rupture limit and can be sutured or cut with an electric energy device such as an electric scalpel.

<Salt>
The salt is not particularly limited as long as it is a compound that can impart electrical conductivity to a hydrogel object formed using the organic-inorganic composite hydrogel precursor liquid, and can be appropriately selected depending on the purpose. Examples of the salt include inorganic salts and organic salts.
Examples of inorganic salts include potassium nitrate (KNO ₃ ), potassium chloride (KCl), potassium sulfate (K ₂ SO ₄ ), sodium chloride (NaCl), and iron (III) chloride hexahydrate.
Examples of organic salts include sodium acetate, methylamine hydrochloride, and aniline hydrochloride.
The salt content is preferably 1% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 10% by mass or less, based on the total amount of the organic-inorganic composite hydrogel precursor liquid.
When the salt content is from 1% by mass to 20% by mass, it is possible to form a hydrogel-modeled object that has excellent compressive stress and rupture limit and can be sutured or cut with an electric energy device such as an electric scalpel.

<Water>
By including water, a hydrogel-modeled object can be formed using the organic-inorganic composite hydrogel precursor liquid.
The water is not particularly limited and can be appropriately selected depending on the purpose. Examples include pure water such as ion-exchanged water, ultrafiltered water, reverse osmosis water, and distilled water, and ultrapure water.
Other components such as organic solvents may be dissolved or dispersed in the water depending on the purpose, such as imparting moisture retention, antibacterial properties, electrical conductivity, or adjusting hardness.
The water content can be appropriately selected depending on the purpose, but is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50.0% by mass or more, based on the total amount of the organic-inorganic composite hydrogel precursor liquid, and is preferably 90% by mass or less, and more preferably 80% by mass or less.
In addition, other components such as organic solvents may be dissolved or dispersed in the water depending on the purpose, such as imparting moisture retention, antibacterial properties, electrical conductivity, or adjusting hardness.

<Chelating agent>
The chelating agent is not particularly limited as long as it is a compound having a chelating effect and can be appropriately selected depending on the purpose, and examples thereof include aminocarboxylic acid chelating agents, chelating metal salts, carboxylic acid chelating agents, etc. These may be used alone or in combination of two or more.

Examples of the aminocarboxylic acid chelating agent include ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA), triethylenetetraaminehexaacetic acid (TTHA), 1,2-diaminopropane-N,N,N',N'-tetraacetic acid (PDTA), N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), ethylenediamine-N,N'-disuccinic acid ( Examples include EDDS), dihydroxyethylglycine (DHEG), 1,3-diamino-2-propanol-N,N,N',N'-tetraacetic acid (DPTA-OH), hydroxyiminodiacetic acid (HIDA), ethylene glycol bis(β-aminoethyl ether)-N,N,N',N'-tetraacetic acid (GEDTA), dicarboxymethylglutamic acid (CMGA), N,N,N',N'-tetramethylethylenediamine, and phytic acid. These may be used alone or in combination of two or more.

Examples of the chelate metal salt include metal salts of ethylenediaminetetraacetic acid and metal salts of diethylenetriaminepentaacetic acid. These may be used alone or in combination of two or more.

Examples of the carboxylic acid-based chelating agent include gluconic acid, succinic acid, and citric acid. These may be used alone or in combination of two or more. The inclusion of a chelating agent stabilizes the dispersion of the metal oxide and inhibits gelation of the organic/inorganic hydrogel precursor liquid.

The content of the chelating agent is preferably 0.1% by mass or more and 5% by mass or less, and more preferably 0.1% by mass or more and 2% by mass or less, relative to the total amount of the organic-inorganic composite hydrogel precursor liquid.

<Other ingredients>
The other components are not particularly limited and can be appropriately selected depending on the purpose. Examples of the other components include stabilizers, surface treatment agents, polymerization initiators, colorants, viscosity modifiers, adhesion promoters, antioxidants, antiaging agents, crosslinking accelerators, ultraviolet absorbers, plasticizers, preservatives, dispersants, and pH adjusters.

-Stabilizer-
A stabilizer may be used as needed to stabilize the liquid properties, and examples of the stabilizer include high-concentration phosphates, glycols, and nonionic surfactants.

-Surface treatment agent-
Examples of the surface treatment agent include polyester resin, polyvinyl acetate resin, silicone resin, coumarone resin, fatty acid ester, glyceride, wax, and the like.

- Polymerization initiator -
Examples of the polymerization initiator include a thermal polymerization initiator, a photopolymerization initiator, etc. In the case of a stereolithography method, a photopolymerization initiator is used, and in the case of a mold molding method, both a thermal polymerization initiator and a photopolymerization initiator can be used.

As the photopolymerization initiator, any substance that generates radicals when irradiated with light, particularly ultraviolet light having a wavelength of 220 nm to 500 nm, can be used.
Examples of photopolymerization initiators include acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, benzophenone, 2-chlorobenzophenone, p,p'-dichlorobenzophenone, p,p-bisdiethylaminobenzophenone, Michler's ketone, benzil, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-propyl ether, benzoin isobutyl ether, benzoin-n-butyl ether, benzyl methyl ketal, thioxanthone, 2-chlorothioxanthone, 2-hydroxy-2-methyl-1-phenyl-1-one, 1-(4-isopropylphenyl)2-hydroxy-2-methylpropan-1-one, methylbenzoyl formate, 1-hydroxycyclohexyl phenyl ketone, azobisisobutyronitrile, benzoyl peroxide, and di-tert-butyl peroxide. These may be used alone or in combination of two or more.

There are no particular restrictions on the thermal polymerization initiator and it can be selected appropriately depending on the purpose. Examples include azo initiators, peroxide initiators, persulfate initiators, and redox (oxidation-reduction) initiators.

Commercially available azo initiators can be used, such as VA-044, VA-46B, V-50, VA-057, VA-061, VA-067, VA-086, 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (VAZO 33), 2,2'-azobis(2-amidinopropane) dihydrochloride (VAZO 50), 2,2'-azobis(2,4-dimethylvaleronitrile) (VAZO 52), 2,2'-azobis(isobutyronitrile) (VAZO 64), 2,2'-azobis-2-methylbutyronitrile (VAZO 67), and 1,1-azobis(1-cyclohexanecarbonitrile) (VAZO 88) (all available from DuPont). (Available from the Chemical Company of America; "VAZO" is a trademark.), 2,2'-azobis(2-cyclopropylpropionitrile), 2,2'-azobis(methyl isobutyrate) (V-601) (available from Wako Pure Chemical Industries, Ltd.), etc.

Examples of peroxide initiators include benzoyl peroxide, acetyl peroxide, lauroyl peroxide, decanoyl peroxide, dicetyl peroxydicarbonate, di(4-t-butylcyclohexyl)peroxydicarbonate (Perkadox 16S) (available from Akzo Nobel, where "Perkadox" is a trademark), di(2-ethylhexyl)peroxydicarbonate, t-butyl peroxypivalate (Lupersol 11) (available from Elf Atochem, where "Lupersol" is a trademark), t-butylperoxy-2-ethylhexanoate (Trigonox 21-C50) (available from Akzo Nobel, where "Trigonox" is a trademark), and dicumyl peroxide.

Examples of persulfate initiators include potassium persulfate, sodium persulfate, and ammonium persulfate.
Redox (oxidation-reduction) initiators include, for example, combinations of persulfate initiators with reducing agents such as sodium metabisulfite and sodium bisulfite, systems based on organic peroxides and tertiary amines, e.g., systems based on benzoyl peroxide and dimethylaniline, systems based on organic hydroperoxides and transition metals, and systems based on cumene hydroperoxide and cobalt naphthate.

- Coloring materials -
As the coloring material, for example, various pigments or dyes that impart black, white, magenta, cyan, yellow, green, orange, or glossy colors such as gold or silver can be used.
When used in the material jetting method, full-color objects can be produced by using inks of various colors such as black, cyan, magenta, yellow, and white.

As the pigment, inorganic or organic pigments can be used.
Examples of inorganic pigments that can be used include carbon blacks (C.I. Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, iron oxide, and titanium oxide.
Examples of organic pigments include azo pigments such as insoluble azo pigments, condensed azo pigments, azo lakes, and chelate azo pigments; polycyclic pigments such as phthalocyanine pigments, perylene and perinone pigments, anthraquinone pigments, quinacridone pigments, dioxane pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments; dye chelates (e.g., basic dye chelates, acid dye chelates, etc.); dye lakes (e.g., basic dye lakes, acid dye lakes, etc.); nitro pigments, nitroso pigments, aniline black, and daylight fluorescent pigments.
Furthermore, in order to improve the dispersibility of the pigment, a dispersant may be further contained. The dispersant is not particularly limited, but examples thereof include dispersants commonly used in preparing pigment dispersions, such as polymer dispersants.

Dyes include, for example, acid dyes, direct dyes, reactive dyes, and basic dyes.

There are no particular restrictions on the amount of colorant contained, and it can be set appropriately taking into consideration the desired color density and dispersibility in the organic-inorganic composite hydrogel precursor liquid, but it is preferably 0.1% by mass or more and 20% by mass or less of the total amount of the organic-inorganic composite hydrogel precursor liquid.

The organic-inorganic composite hydrogel precursor liquid of the present invention can be prepared using a metal oxide, a monomer, a salt, water, a chelating agent, and, if necessary, other components. There are no particular restrictions on the preparation method or conditions, which can be selected appropriately depending on the purpose. For example, it can be prepared by adding the above components to a dispersing machine such as a ball mill, Kitty mill, disc mill, pin mill, or Dyno mill and mixing them.

The viscosity of the organic-inorganic composite hydrogel precursor liquid is not particularly limited and can be selected appropriately depending on the purpose. However, in the case of the material jetting method, the viscosity at 25°C is preferably 3 mPa·s or more and 40 mPa·s or less, and more preferably 5 mPa·s or more and 30 mPa·s or less. If the viscosity at 25°C is less than 3 mPa·s, the ejection may become unstable during modeling, such as the ejection direction changing or no ejection at all. If the viscosity exceeds 40 mPa·s, ejection may not occur. The viscosity of the contained organic-inorganic composite hydrogel precursor liquid may also be adjusted to these values by changing the temperature of the inkjet head.

In the case of stereolithography, from the viewpoint of stably maintaining the cured product in the modeling tank, the viscosity at 25°C is preferably 50 mPa·s or more, more preferably 100 mPa·s or more, and even more preferably 200 mPa·s or more, and from the viewpoint of handleability, the viscosity is preferably 20,000 mPa·s or less, more preferably 15,000 mPa·s or less, and even more preferably 12,000 mPa·s or less.
The viscosity of the contained organic-inorganic composite hydrogel precursor liquid may be adjusted to these values by changing the temperature of the modeling tank.

In the case of mold molding, the viscosity at 25°C is preferably 3 mPa·s or more and 1000 mPa·s or less, and more preferably 3 mPa·s or more and 100 mPa·s or less. If the viscosity at 25°C exceeds 1000 mPa·s, the high viscosity will reduce handling when pouring into a mold.

The viscosity can be measured at 25°C using, for example, a rotational viscometer (VISCOMATE VM-150III, manufactured by Toki Sangyo Co., Ltd.). The viscosity can be adjusted, for example, by mixing monomers, minerals dispersed in water, or solvents with different viscosities.

(organic-inorganic composite hydrogel)
The organic-inorganic composite hydrogel of the present invention contains a metal oxide, a polymer, a salt, a chelating agent, and water, and may further contain other components as required.
The polymer is a polymer obtained by polymerizing the monomer in the organic-inorganic composite hydrogel precursor liquid.
The metal oxide, salt, chelating agent, water, and other components may be the same as those in the organic-inorganic composite hydrogel precursor liquid.

In the present invention, the term "hydrogel" refers to a structure in which water is trapped within a three-dimensional network structure containing a polymer. When such a three-dimensional network structure is formed by combining a polymer and a mineral, it is particularly referred to as an "organic-inorganic composite hydrogel." Note that hydrogels contain water as their main component; specifically, the water content is preferably 30.0% by mass or more, more preferably 40.0% by mass or more, and even more preferably 50.0% by mass or more, of the total amount of the hydrogel.

(Method for manufacturing a hydrogel modeled object)
The method for producing a hydrogel modeled object of the present invention includes a liquid film formation step of forming a hydrogel precursor liquid film using the organic-inorganic composite hydrogel precursor liquid of the present invention, and a liquid film curing step of curing the hydrogel precursor liquid film to form a layer, and may further include other steps as necessary.
The liquid film forming step is preferably carried out by inkjet printing.

The method for producing a hydrogel modeled object of the present invention involves injecting the organic-inorganic composite hydrogel precursor liquid of the present invention into a mold, allowing the organic-inorganic composite hydrogel precursor liquid to harden, and then removing the mold to produce a hydrogel modeled object.

Specific examples of methods for producing a hydrogel modeled object using the organic-inorganic composite hydrogel precursor liquid of the present invention include the following first to third methods.

<Method for producing a hydrogel modeled object according to the first embodiment>
The first embodiment of the manufacturing method comprises repeating a liquid film formation step of forming an organic-inorganic composite hydrogel precursor liquid film and a liquid film curing step of curing the organic-inorganic composite hydrogel precursor liquid film to form a layer, and then laminating the layers to form a hydrogel-modeled object, and further includes other steps as necessary. The liquid film formation step is preferably performed by inkjet printing, which is generally referred to as a "material jetting method."
The first form of manufacturing method for a hydrogel model object can accommodate color modeling and hybrid modeling with resin-based components by increasing the number of heads, making it possible to simultaneously model colored inks and other resin-based materials.
In the first embodiment of the method for manufacturing a hydrogel model object, each of the steps is repeated multiple times. The number of repetitions cannot be generally determined as it varies depending on the size, shape, and structure of the hydrogel model object to be manufactured. However, it is preferable to repeat the steps multiple times to the height of the hydrogel model object to be manufactured, because a layer thickness in the range of 10 μm to 50 μm per layer allows for accurate manufacturing without peeling.

- Liquid film forming process and liquid film forming means -
The liquid film forming step is a step of applying the organic-inorganic composite hydrogel precursor liquid of the present invention to form an organic-inorganic composite hydrogel precursor liquid film, and is carried out by a liquid film forming means.

The liquid film forming means is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a dispenser method, a spray method, an inkjet method, etc. Note that known devices can be suitably used to implement these methods.
Among these, the dispenser method is excellent in droplet quantity but has a narrow coating area, while the spray method can easily form finely ejected material, has a wide coating area, and is excellent in coating ability but has poor droplet quantity and causes scattering due to the spray flow. For this reason, the inkjet method is particularly preferred in the present invention. The inkjet method has the advantages of better droplet quantity than the spray method, a wider coating area than the dispenser method, and is preferred in that it can form complex three-dimensional shapes with high precision and efficiency.

- Liquid film hardening process and liquid film hardening means -
The liquid film hardening step is a step of hardening the organic-inorganic composite hydrogel precursor liquid film to form a layer, and is carried out by a liquid film hardening means.
In the liquid film curing step, the organic-inorganic composite hydrogel precursor liquid film is cured by irradiating it with active energy rays.
As the active energy ray, light is preferred, and ultraviolet light with a wavelength of 220 nm or more and 400 nm or less is particularly preferred. In addition to ultraviolet light, electron beams, α-rays, β-rays, γ-rays, X-rays, and other light sources that can impart the energy necessary to promote the polymerization reaction of the polymerizable components in the composition are not particularly limited. When a particularly high-energy light source is used, the polymerization reaction can proceed without the use of a polymerization initiator. Furthermore, in the case of ultraviolet irradiation, mercury-free irradiation is strongly desired from the perspective of environmental protection, and replacement with GaN-based semiconductor ultraviolet light-emitting devices is extremely useful from both an industrial and environmental perspective. Furthermore, ultraviolet light-emitting diodes (UV-LEDs) and ultraviolet laser diodes (UV-LDs) are preferred as ultraviolet light sources due to their compact size, long life, high efficiency, and low cost.

Commercially available equipment can be used to manufacture three-dimensional objects using the "material jetting method." Examples of commercially available equipment for manufacturing three-dimensional objects using the material jetting method include the Agilista (manufactured by Keyence Corporation).

FIG. 1 shows a three-dimensional printer 10 that uses the "material jetting method." Using a head unit with an array of inkjet heads, an organic-inorganic composite hydrogel precursor liquid is sprayed from a liquid material-jetting head unit 11 for forming a model, and a liquid material for forming a support is sprayed from liquid material-jetting head units 12, 12 for forming a support. The organic-inorganic composite hydrogel precursor liquid and the liquid material for forming a support are layered while being cured by adjacent ultraviolet irradiators 13, 13. The three-dimensional printer 10 also includes a support substrate 14 for forming a model, and a smoothing member 16.
To maintain a constant gap between the liquid material jetting head units 11 and 12 and the ultraviolet irradiator 13 and the hydrogel model 17 and the support 18, the stage 15 is lowered according to the number of layers to be stacked.
In the three-dimensional printer 10, the ultraviolet irradiators 13, 13 are used when moving in either the direction of arrows A or B, and the heat generated by the ultraviolet irradiation smoothes the surface of the layered liquid material for forming the support, thereby improving the dimensional stability of the hydrogel object.
After the modeling was completed, the hydrogel model 17 and the support 18 were pulled horizontally to separate them, as shown in FIG. 2. The support 18 was separated as a single unit, and the hydrogel model 17 could be easily removed.

<Method for producing a hydrogel modeled object according to the second embodiment>
The second embodiment of the method for producing a hydrogel modeled object may be, for example, a stereolithography method.
The stereolithography method involves exposing an organic-inorganic composite hydrogel precursor liquid layer by layer, allowing it to cure and stack sequentially to form a hydrogel object.
Each layer of this laminate is obtained by irradiating the liquid surface of the organic-inorganic composite hydrogel precursor liquid with light. The liquid surface can be leveled using a recoater or the like. At this time, selective irradiation with light can produce a cured product (cross-sectional cured layer) with a cross-section of the desired pattern.
In the second embodiment of the method for producing a hydrogel-modeled object, the organic-inorganic composite hydrogel precursor liquid is irradiated with light to form a cured product (cross-sectional cured layer) of the organic-inorganic composite hydrogel precursor liquid, and then the organic-inorganic composite hydrogel precursor liquid is again supplied onto this cured product (cross-sectional cured layer) and irradiated with light to form a further cured product (cross-sectional cured layer) of the organic-inorganic composite hydrogel precursor liquid. By repeating this process, a hydrogel-modeled object is obtained in which a plurality of cured products (cross-sectional cured layers) are stacked and integrated.

The means for selectively irradiating the organic-inorganic composite hydrogel liquid precursor with light is not particularly limited, and various means can be employed, such as (a) a means for irradiating the organic-inorganic composite hydrogel liquid precursor with laser light or convergent light obtained using a lens, mirror, or the like while scanning the organic-inorganic composite hydrogel liquid precursor, (b) a means for using a mask having light-transmitting portions with a predetermined pattern and irradiating the organic-inorganic composite hydrogel liquid precursor with unconverged light through the mask, (c) a means for using a light-guiding member formed by bundling a large number of optical fibers and irradiating the organic-inorganic composite hydrogel liquid precursor with light through optical fibers corresponding to the predetermined pattern on the light-guiding member, and (d) a means for repeatedly performing batch exposure for each predetermined region.
In addition, in the means using a mask as described above in (b), a mask that electro-optically forms a mask image consisting of light-transmitting areas and light-non-transmitting areas according to a predetermined pattern can also be used, based on the same principle as a liquid crystal display device.

When the desired hydrogel object has minute features or requires high dimensional accuracy, it is preferable to employ a means for scanning with a laser beam having a small spot diameter as a means for selectively irradiating the organic-inorganic composite hydrogel precursor liquid with light.
When an organic-inorganic composite hydrogel liquid precursor is contained in a container, the surface to be irradiated with light (for example, the scanning plane of the convergent light) may be either the liquid surface of the organic-inorganic composite hydrogel liquid precursor or the surface in contact with the container wall of the light-transmitting container. When the liquid surface of the organic-inorganic composite hydrogel liquid precursor or the surface in contact with the container wall is used as the surface to be irradiated with light, the light can be irradiated directly from outside the container or through the container wall.

As described above, the hydrogel-shaped object of the present invention can be produced by a photolithography method such as photo-assisted fabrication. In photolithography, a specific portion of an organic-inorganic composite hydrogel precursor liquid is cured, and then the light irradiation position (irradiation surface) is moved continuously or stepwise from the cured portion to the uncured portion, thereby laminating the cured portions to form a desired three-dimensional shape. The irradiation position can be moved by various methods, such as moving the light source, the container containing the organic-inorganic composite hydrogel precursor liquid, or the cured portion of the organic-inorganic composite hydrogel precursor liquid, or adding additional organic-inorganic composite hydrogel precursor liquid to the container.
A commercially available stereolithography modeling apparatus can be used, such as Form2 (manufactured by Formlabs).

<Method for producing a hydrogel modeled object according to the third embodiment>
The third embodiment of the method for producing a hydrogel modeled object is a casting method using a mold.
This method involves fabricating a mold that serves as a template. The mold can be fabricated using a 3D printer, material jetting, stereolithography, binder jetting, FDM, or other methods. Alternatively, CNC cutting can be used.
The hollow interior of the mold thus prepared is then filled with the organic-inorganic composite hydrogel precursor liquid. If the mold is made of a transparent resin, the organic-inorganic composite hydrogel precursor liquid can be made UV-curable with a photopolymerization initiator, allowing the organic-inorganic composite hydrogel precursor liquid to be easily cured using a UV lamp.
When the mold is made of an impermeable resin, the organic-inorganic composite hydrogel precursor liquid can be hardened by thermal energy by making the organic-inorganic composite hydrogel precursor liquid a thermosetting type using a thermal polymerization initiator.
After the organic-inorganic composite hydrogel liquid precursor is hardened by these methods, the template can be removed by peeling or crushing, and the hydrogel modeled object can be taken out.

Examples of the present invention are described below, but the present invention is not limited to these examples in any way.

Example 1
<Preparation of organic-inorganic composite hydrogel precursor liquid>
First, 1.4 parts by mass of synthetic hectorite (Laponite RD, manufactured by Rockwood) having a composition of [ _{Mg5.34Li0.66Si8O20} (OH) ₄ ]Na ^- _0.66 as a metal oxide was _gradually added to 74.5 parts by mass _of pure water while stirring, _and then 0.1 parts by mass of etidronic acid (1-hydroxyethane-1,1-diphosphonic acid, manufactured by Tokyo Chemical Industry Co., Ltd.) was added and stirred to prepare a dispersion.
Next, 22.4 parts by mass of N,N-dimethylacrylamide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and 0.2 parts by mass of methylenebisacrylamide (manufactured by Tokyo Chemical Industry Co., Ltd.), which had been passed through an activated alumina column to remove the polymerization inhibitor, were added as polymerizable monomers to the obtained dispersion.
Next, 0.1 parts by mass of N,N,N',N'-tetramethylethylenediamine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a chelating agent.
Next, 0.3 parts by mass of a 10% by mass aqueous solution of ammonium persulfate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a polymerization initiator, and the mixture was stirred.
Next, 1 part by mass of NaCl (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a salt and stirred to prepare an organic-inorganic composite hydrogel precursor liquid of Example 1.

Next, using the obtained organic-inorganic composite hydrogel precursor liquid, breaking limit test pieces, compressive stress test pieces, and medical organ models were prepared as described below, and breaking limit tests, compressive stress tests, incision tests, and suture tests were conducted as described below. The results are shown in Table 1.

<Breaking limit test>
- Preparation of fracture limit test pieces (mold making) -
A test pattern (dumbbell-shaped No. 3, based on JIS K6251) was cut into a polytetrafluoroethylene (PTFE) block to a depth of 5 mm. This mold was filled with an organic-inorganic composite hydrogel precursor liquid and allowed to harden for 24 hours under a nitrogen atmosphere to prepare a fracture limit test piece. The fracture limit of the prepared fracture limit test piece was measured using the method described below.

- Measurement of breaking limit -
The prepared fracture limit test pieces were subjected to a test at a tensile speed of 500 mm/min using a tensile tester (AG-10kNX, manufactured by Shimadzu Corporation) in accordance with JIS K 6251. During the tensile test, the elongation (%) was calculated from the change in the gauge length, and this was used to evaluate the fracture limit.
When used as a medical organ model material, a breaking limit of 300% or more is preferable in order to exhibit flexibility similar to that of an organ. Note that in this tensile testing machine, specimens that show no deformation and exceed the measurement limit of 10 kN, resulting in an error, are considered outside the measurement range.

<Compression stress test>
-Preparation of compressive stress test specimens (mold making)-
A test pattern (30 mm x 30 mm x 10 mm) was formed in a polytetrafluoroethylene (PTFE) block by cutting. This mold was filled with an organic-inorganic composite hydrogel precursor liquid and allowed to harden at room temperature under a nitrogen atmosphere for 24 hours, producing a 30 mm x 30 mm x 10 mm compressive stress test piece. The compressive stress and Young's modulus were evaluated using this test piece according to the following method.

- Measurement of compressive stress and Young's modulus -
The compression tester and measurement method used for evaluating the compressive stress are as follows.
A universal testing machine (Shimadzu Corporation, AG-I), a 1 kN load cell, and a 1 kN compression jig were installed, and the compressive stress test models for each of the above examples and comparative examples were placed in the machine. The stress against the compression applied to the load cell was recorded in a computer, and the stress against the displacement was plotted to evaluate the compressive stress at 60% compression. In addition, Young's modulus, which serves as an index of organ texture, was measured from the slope of the initial displacement.
When used as a medical organ model material, in order to exhibit flexibility similar to that of an organ, it is preferable that the compressive stress be in the range of 0.1 MPa to 1.5 MPa and the Young's modulus be in the range of 0.05 MPa to 1 MPa. Note that compressive stresses that do not cause deformation of the sample in this testing machine and exceed the measurement limit of 1 kN, resulting in an error, are considered outside the measurement range.

<Incision test and suture test>
- Creation of medical organ models for incision and suture tests (mold making) -
A casting mold simulating the kidney parenchyma was fabricated using a stereolithography modeling device (Form2, manufactured by Formlabs). An organic-inorganic composite hydrogel precursor liquid was poured into this mold and allowed to harden for 24 hours under a nitrogen atmosphere. The mold was then removed to obtain a medical organ model simulating the kidney. Using this, an incision test and a suture test were performed according to the methods described below.

-Incision test-
The obtained medical organ model was subjected to an incision test using a high-frequency electric scalpel as an energy device.
The cutting test was carried out using an electric scalpel PROG (DS3M, manufactured by Morita Corporation) with a C-1 tip (blade) set in CUT mode. The cutting test was divided into the following initial cutting ability and continuous cutting ability.

--Evaluation of initial cutting ability--
The initial cutting ability was evaluated to confirm whether the medical organ model was conductive and compatible with an electric scalpel. When the electric scalpel was held at a 45-degree angle and the blade was pushed in 10 mm, whether the blade sank while burning through the medical organ model was evaluated according to the following criteria.
[Evaluation criteria]
〇: When the blade can be inserted 10 mm after being burned off △: When the conductivity is insufficient and smoke comes out but the blade cannot be cut, or when the blade stops cutting halfway through ×: When the blade cannot be cut at all

--Evaluation of continuous cutting ability--
The continuous cutting ability was evaluated as an evaluation of operability, assessing whether the medical organ model could be cut smoothly and continuously. Following the initial cutting ability, a linear cut of 10 mm depth was made over a length of 50 mm from a state where the blade was inserted 10 mm, and the continuous cutting ability was evaluated according to the following criteria.
[Evaluation criteria]
〇: When the medical organ model was burned without any problems and a cut was made. △: When soot adhered to the electric scalpel blade during the process, making it difficult to cut, but it was able to cut 50 mm. ×: When it was not possible to cut at all (no reaction or the electric scalpel blade did not go in).

-Suture test-
In the suture test, a 30 mm long and 10 mm deep incision was made in the medical organ model with a cutter knife, and then an LTR-1 training needle suture (manufactured by Fujimori Sangyo Co., Ltd.) was used as the surgical needle thread, and the thread was passed through the needle three times in a zigzag pattern across the incision. After that, both ends of the thread were pinched, and it was confirmed whether or not the medical organ model could be lifted, and the test was evaluated according to the following criteria.
[Evaluation criteria]
〇: The organ model was sutured without any problems and could be lifted up. △: The organ model was sutured, but it broke when lifted up. ×: The organ model broke when the needle was passed through, or the organ model was too hard to pass the needle through.

Example 2
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel liquid precursor of Example 2 was prepared in the same manner as in Example 1, except that the amount of pure water was changed to 75.4 parts by mass and the amount of NaCl was changed to 0.1 parts by mass.
Next, using the obtained organic-inorganic composite hydrogel precursor liquid, a breaking limit test piece, a compressive stress test piece, and a medical organ model were prepared in the same manner as in Example 1, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 1.

Example 3
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel precursor liquid of Example 3 was prepared in the same manner as in Example 1, except that the amount of pure water in Example 1 was changed to 68.5 parts by mass, the amount of Laponite RD to 1.2 parts by mass, the amount of N,N-dimethylacrylamide to 19.4 parts by mass, the amount of N,N,N',N'-tetramethylethylenediamine to 0.3 parts by mass, and the amount of NaCl to 10 parts by mass.
Next, using the obtained organic-inorganic composite hydrogel precursor liquid, a breaking limit test piece, a compressive stress test piece, and a medical organ model were prepared in the same manner as in Example 1, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 1.

Example 4
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel liquid precursor of Example 4 was prepared in the same manner as in Example 1, except that the amount of Laponite RD was changed to 4.2 parts by mass and the amount of N,N-dimethylacrylamide was changed to 19.6 parts by mass.
Next, using the obtained organic-inorganic composite hydrogel precursor liquid, a breaking limit test piece, a compressive stress test piece, and a medical organ model were prepared in the same manner as in Example 1, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 1.

Example 5
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel precursor liquid of Example 5 was prepared in the same manner as in Example 1, except that NaCl in Example 1 was replaced with iron (III) chloride hexahydrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).
Next, using the obtained organic-inorganic composite hydrogel precursor liquid, a breaking limit test piece, a compressive stress test piece, and a medical organ model were prepared in the same manner as in Example 1, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 1.

Example 6
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel liquid precursor of Example 6 was prepared in the same manner as in Example 1, except that ammonium persulfate in Example 1 was replaced with 1-hydroxycyclohexyl phenyl ketone (trade name: Irgacure 184, manufactured by BASF Corporation).
Next, the obtained organic-inorganic composite hydrogel precursor liquid was used to prepare a breaking limit test piece, a compressive stress test piece, and a medical organ model similar to those in Example 1 by the following material jetting method, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 2.

-Modeling using the Material Jetting (MJ) method-
The organic-inorganic composite hydrogel precursor liquid was used as a modeling agent in a MaterialART-3DU1 (manufactured by Microjet Co., Ltd.) 3D printer using the material jetting (MJ) method, and a breaking limit test piece, a compressive stress test piece, and a medical organ model similar to those in Example 1 were directly modeled.

Example 7
Using the organic-inorganic composite hydrogel precursor liquid of Example 6, a breaking limit test piece, a compressive stress test piece, and a medical organ model similar to those in Example 1 were prepared by the following stereolithography method, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 2.

-Modeling using the stereolithography (SLA) method-
Using a Form2 (manufactured by Formlabs) as a 3D printer by the stereolithography (SLA) method and using the organic-inorganic composite hydrogel precursor liquid of Example 6 as the modeling ink, a breaking limit test piece, a compressive stress test piece, and a medical organ model similar to those of Example 1 were directly modeled.

(Comparative Example 1)
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel liquid precursor of Comparative Example 1 was prepared in the same manner as in Example 1, except that NaCl was not added and the amount of pure water was changed to 75.5 parts by mass.
Next, using the obtained organic-inorganic composite hydrogel precursor liquid, a breaking limit test piece, a compressive stress test piece, and a medical organ model were prepared in the same manner as in Example 1, and a breaking limit test, a compressive stress test, an incision test, and a suture test were carried out in the same manner as in Example 1. The results are shown in Table 2.

(Comparative Example 2)
Using a commercially available 3D printer, Agilista (manufactured by Keyence Corporation), and model agent AR-M2 (manufactured by Keyence Corporation), the same fracture limit test pieces, compressive stress test pieces, and medical organ models as in Example 1 were directly modeled, and fracture limit tests, compressive stress tests, incision tests, and suture tests were performed in the same manner as in Example 1. The results are shown in Table 2.

(Comparative Example 3)
Using a commercially available stereolithography (SLA) 3D printer, Form2 (manufactured by Formlabs Co., Ltd.), and clear resin (manufactured by Formlabs Co., Ltd.), fracture limit test pieces, compressive stress test pieces, and medical organ models similar to those in Example 1 were directly modeled, and fracture limit tests, compressive stress tests, incision tests, and suture tests were performed in the same manner as in Example 1. The results are shown in Table 2.

(Comparative Example 4)
- Preparation of organic-inorganic composite hydrogel precursor liquid -
An organic-inorganic composite hydrogel precursor liquid of Comparative Example 4 was prepared in the same manner as in Example 1, except that N,N,N',N'-tetramethylethylenediamine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was not added as a chelating agent.
In this case, 1 part by mass of NaCl (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a salt and stirred, resulting in an increase in viscosity of the entire liquid and a loss of fluidity, making it unsuitable as a modeling ink and making modeling impossible. The results are shown in Table 2.

The results in Tables 1 and 2 show that, compared with Comparative Examples 1 to 3, Examples 1 to 7 can be incised using an electric scalpel.
Example 2, in which the amount of salt added was small, had lower electrical conductivity than the other examples, and therefore the cutting ability was slightly reduced.
The shaped object of Comparative Example 1 was not able to be treated with an electric scalpel because no salt was added.
The shaped articles of Comparative Examples 2 and 3 were very hard and unsuitable for use as medical organ models.

The present invention includes, for example, the following aspects.
<1> A metal oxide,
A monomer,
Salt and
A chelating agent;
Water and
The organic-inorganic composite hydrogel precursor liquid is characterized by comprising:
<2> The organic-inorganic composite hydrogel liquid precursor according to <1>, wherein the salt is an inorganic salt.
<3> The organic-inorganic composite hydrogel liquid precursor according to any one of <1> and <2>, wherein the content of the salt is 0.1 mass % or more and 20 mass % or less relative to the total amount of the organic-inorganic composite hydrogel liquid precursor.
<4> The organic-inorganic composite hydrogel liquid precursor according to any one of <1> to <3>, wherein the content of the chelating agent is 0.1% by mass or more and 5% by mass or less relative to the total amount of the organic-inorganic composite hydrogel liquid precursor.
<5> The organic-inorganic composite hydrogel liquid precursor according to any one of <1> to <4>, wherein the metal oxide is any one of metal oxide fine particles, composite metal oxide fine particles, and layered mineral.
<6> The organic-inorganic composite hydrogel liquid precursor according to any one of <1> to <5>, wherein the content of the metal oxide is 10 mass % or less.
<7> A hydrogel modeled object obtained by using the organic-inorganic composite hydrogel liquid precursor according to any one of <1> to <6>.
<8> A liquid film forming step of forming a hydrogel precursor liquid film using the organic-inorganic composite hydrogel precursor liquid according to any one of <1> to <6>;
a liquid film curing step of curing the hydrogel precursor liquid film to form a layer;
The method for producing a hydrogel modeled object is characterized by comprising the steps of:
<9> An organic-inorganic composite hydrogel comprising a metal oxide, a polymer, a salt, a chelating agent, and water.

The organic-inorganic composite hydrogel precursor liquid described in any one of <1> to <6>, the hydrogel modeled object described in <7>, the method for producing a hydrogel modeled object described in <8>, and the organic-inorganic composite hydrogel described in <9> can solve various problems encountered in the past and achieve the object of the present invention.

10. Three-dimensional printer 17. Hydrogel modeling

JP 2016-176006 A (Patent No. 6520266 A)

Claims (8)

Layered minerals;
a monomer having a radical polymerizable functional group;
a water-soluble inorganic salt;
A chelating agent;
Water and
a radical polymerization initiator different from the water-soluble inorganic salt;
Including,
the number of the radical polymerizable functional group in the monomer having a radical polymerizable functional group is one, and the radical polymerizable functional group is an acrylamide group;
the water-soluble inorganic salt is at least one selected from the group consisting of potassium nitrate, potassium chloride, potassium sulfate, sodium chloride, and iron (III) chloride hexahydrate;
the chelating agent is N,N,N',N'-tetramethylethylenediamine;
the content of the layered mineral is 1% by mass or more and 10% by mass or less with respect to the total amount of the organic-inorganic composite hydrogel precursor liquid,
the content of the monomer having a radically polymerizable functional group is 0.5% by mass or more and 40 % by mass or less with respect to the total amount of the organic-inorganic composite hydrogel precursor liquid,
the content of the water-soluble inorganic salt is 0.1% by mass or more and 20% by mass or less with respect to the total amount of the organic-inorganic composite hydrogel precursor liquid,
the content of the chelating agent is 0.1% by mass or more and 5% by mass or less with respect to the total amount of the organic-inorganic composite hydrogel precursor liquid,
The organic-inorganic composite hydrogel liquid precursor is characterized in that the content of water is 50.0 mass % or more based on the total amount of the organic-inorganic composite hydrogel liquid precursor. The organic-inorganic composite hydrogel precursor liquid according to claim 1, wherein the layered mineral is a water-swellable layered clay mineral. 3. The organic-inorganic hybrid hydrogel liquid precursor according to claim 1, wherein the monomer having a radically polymerizable functional group is N,N-dimethylacrylamide . The organic-inorganic composite hydrogel precursor liquid according to any one of claims 1 to 3, wherein the water-soluble inorganic salt is at least one of sodium chloride and iron (III) chloride hexahydrate. A hydrogel modeled object obtained by using the organic-inorganic composite hydrogel liquid precursor according to claim 1 . a liquid film forming step of forming a hydrogel precursor liquid film using the organic-inorganic composite hydrogel precursor liquid according to any one of claims 1 to 4;
a liquid film curing step of curing the hydrogel precursor liquid film to form a layer;
A method for producing a hydrogel modeled object, comprising: The method for producing a hydrogel modeled object according to claim 6 , wherein the liquid film forming step is performed by inkjet printing. 5. A method for producing a hydrogel modeled object, comprising: injecting the organic-inorganic composite hydrogel precursor liquid according to claim 1 into a mold; curing the organic-inorganic composite hydrogel precursor liquid; and removing the mold to produce a hydrogel modeled object.