JP6724303B2 - Method for manufacturing three-dimensional object - Google Patents

Description

The present invention relates to a method for manufacturing a three-dimensional object and a manufacturing apparatus therefor.

Conventionally, as a three-dimensional modeling method, a method has been proposed in which a liquid photo-curable resin is irradiated with laser light, particularly ultraviolet light, one layer at a time to produce a three-dimensional three-dimensional structure (for example, Patent Document 1). reference). However, in this proposed method, it is necessary to store a large amount of liquid photocurable resin, and it is necessary to upsize the device. In addition, there is a problem that it is necessary to control the temperature and the like in order to stabilize the quality of the liquid photocurable resin.
Further, in recent years, there has been disclosed an inkjet stereolithography method in which a liquid photo-curable resin is imaged on a required portion of the molded article by an inkjet method, and a three-dimensional molded article is formed by stacking the images. In such an inkjet stereolithography method, a method has been proposed in which a member support different from the three-dimensional object is formed at the same time to prevent the three-dimensional object from being deformed or dropped during the three-dimensional object (for example, Patent Document 2). And 3).
In addition, a method of performing a smoothing process for each layer formation when performing three-dimensional modeling has been proposed (see, for example, Patent Document 4).

Recently, there has been an increasing need for gel-like or soft three-dimensional objects with a three-dimensional and precise structure such as a scaffolding material for cells used for medical organs and regenerative medicine. A method for producing a three-dimensional object that can be reproduced from the data has not been provided yet.

It is an object of the present invention to provide a method for producing a three-dimensional object which allows simple and efficient production of a complicated and fine three-dimensional object represented by an organ model or the like.

The method for producing a three-dimensional structure of the present invention as a means for solving the above problems, water, and a first step of applying a first liquid containing at least a hydrogel precursor to form a film,
A second step of curing the film formed in the first step,
A third step of smoothing the film cured in the second step,
Repeat multiple times.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the three-dimensional molded object which can manufacture a complicated and fine three-dimensional molded object represented by an organ model etc. simply and efficiently can be provided.

FIG. 1 is a schematic diagram showing an example of a layered mineral and a state in which the layered mineral is dispersed in water. FIG. 2 is a schematic view showing an example of a manufacturing apparatus for a three-dimensional object according to the present invention. FIG. 3 is a schematic view showing another example of the apparatus for manufacturing a three-dimensional object according to the present invention. FIG. 4 is a schematic view showing still another example of the manufacturing apparatus for a three-dimensional molded object of the present invention. FIG. 5: is a figure which shows the state of the intermediate body (before support peeling) manufactured by the manufacturing method of a three-dimensional molded item. FIG. 6 is a diagram showing a state after peeling produced by the method for producing a three-dimensional molded item. FIG. 7 is a diagram for explaining measurement of an error in the vertical direction and an error in the horizontal direction of the molded body after peeling.

(Method for manufacturing three-dimensional object and apparatus for manufacturing three-dimensional object)
The method for producing a three-dimensional object according to the first aspect of the present invention includes a first step, a second step, and a third step, and further includes other steps as necessary.
An apparatus for manufacturing a three-dimensional object according to the first aspect of the present invention has a first means, a second means, and a third means, and further has other means as necessary. Become.

<First step and first means>
The first step is a step of applying a first liquid containing water and a hydrogel precursor to form a film, and can be performed by the first means.

The means for applying the first liquid as the first means is not particularly limited as long as it is a system in which droplets can be applied to a target place with appropriate accuracy, and can be appropriately selected according to the purpose. Examples of the method include a dispenser method, a spray method, and an inkjet method. A known device can be preferably used to implement these methods.
Among these, the dispenser method is excellent in the quantitativeness of droplets, but the coating area is narrow, and the spray method can easily form a fine discharge product, the coating area is wide, and the coating property is excellent, The quantitativeness of the droplets is poor and scattering due to the spray flow occurs. Therefore, the inkjet method is particularly preferable in the present invention. The ink-jet method is more advantageous than the spray method in that the droplet quantity is good, the coating area is wider than the dispenser method, and it is preferable in that a complicated three-dimensional shape can be formed accurately and efficiently. ..

In the case of the inkjet method, it has a nozzle capable of ejecting the first liquid. In addition, as the nozzle, a nozzle in a known inkjet printer can be preferably used, and as the inkjet nozzle, for example, GEN4 manufactured by Ricoh Industry Co., Ltd. can be preferably cited. This ink jet nozzle is preferable from the viewpoint that the amount of liquid that can be dropped from the head portion at one time is large and the coating area is wide, so that the coating speed can be increased.

<<First liquid>>
The first liquid contains water and a hydrogel precursor, and further contains other components as necessary. The first liquid is also referred to as a “liquid material for soft molded bodies”.

-Water-
As the water, for example, deionized water, ultrafiltered water, reverse osmosis water, pure water such as distilled water, or ultrapure water can be used.
Other components such as an organic solvent may be dissolved or dispersed in the water depending on the purpose of imparting moisturizing properties, imparting antibacterial properties, imparting conductivity, adjusting hardness, and the like.
The content of the water is not particularly limited and can be appropriately selected depending on the purpose.

-Hydrogel precursor-
The hydrogel precursor contains a water-dispersible mineral and a polymerizable monomer, and further contains other components as necessary.

--- Minerals dispersible in water ---
The mineral dispersible in water is appropriately selected depending on the intended purpose without any limitation, and examples thereof include layered minerals.
The layered mineral is preferably a layered mineral dispersed in water in a single layer state.
Here, as shown in the upper diagram of FIG. 1, the layered mineral has a state in which two-dimensional disk-shaped crystals having a unit cell in the crystal are stacked, and when the layered mineral is dispersed in water, As shown in the lower diagram of FIG. 1, each single layer is separated into a disc-shaped crystal.
The layered mineral is appropriately selected depending on the intended purpose without any limitation, and examples thereof include a water-swellable layered clay mineral.
Examples of the water-swellable layered clay mineral include water-swellable smectite and water-swellable mica. More specifically, water-swellable hectorite containing sodium as an interlayer ion, water-swellable montmorillonite, water-swellable saponite, water-swellable synthetic mica, etc. may be mentioned.
The water swelling property means that water molecules are inserted between layers of the layered mineral and dispersed in water as shown in FIG.
As the water-swellable layered clay mineral, the above-exemplified compounds may be used alone or in combination of two or more, or may be appropriately synthesized. It may be a commercially available product.
Examples of the commercially available product include synthetic hectorite (Laponite XLG, manufactured by Rockwood), SWN (manufactured by Coop Chemical Ltd.), and fluorinated hectorite SWF (manufactured by Coop Chemical Ltd.). Among these, synthetic hectorite is preferable.
The content of the layered mineral is preferably 1% by mass or more and 40% by mass or less, and more preferably 1% by mass or more and 15% by mass or less, based on the total amount of the first liquid. When the content is in the range of 1% by mass or more and 40% by mass or less, the viscosity of the first liquid is appropriate, and the ejection property with an inkjet nozzle and the hardness of the three-dimensional object become good.

---Polymerizable monomer---
Examples of the polymerizable monomer include acrylamide, N-substituted acrylamide derivatives, N,N-disubstituted acrylamide derivatives, N-substituted methacrylamide derivatives, N,N-disubstituted methacrylamide derivatives, and the like. Examples include acrylamide, N,N-dimethylacrylamide, N-isopropylacrylamide, N-acryloylmorpholine and the like. These may be used alone or in combination of two or more.
By polymerizing the polymerizable monomer, a polymer having an amide group, an amino group, a hydroxyl group, a tetramethylammonium group, a silanol group, an epoxy group or the like can be obtained.
The polymer having an amide group, an amino group, a hydroxyl group, a tetramethylammonium group, a silanol group, an epoxy group, etc. is an advantageous constituent component for maintaining the strength of the hydrogel.
The content of the polymerizable monomer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.5% by mass or more and 20% by mass or less with respect to the total amount of the first liquid.

-Other ingredients-
The other components are not particularly limited and can be appropriately selected depending on the purpose,
For example, surfactants, stabilizers, surface treatment agents, polymerization initiators, colorants, viscosity modifiers, adhesion promoters, antioxidants, antioxidants, cross-linking accelerators, UV absorbers, plasticizers, preservatives. Agents, organic solvents, dispersants and the like.

-Physical properties of the first liquid-
The surface tension of the first liquid is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 20 mN/m or more and 45 mN/m or less, and 25 mN/m or more and 34 mN/m or less. More preferable.
When the surface tension is 20 mN/m or more and 45 mN/m or less, excellent ejection of the first liquid can be performed during three-dimensional modeling.
The surface tension can be measured using, for example, a surface tensiometer (automatic contact angle meter DM-701, manufactured by Kyowa Interface Science Co., Ltd.).

The viscosity of the first liquid is appropriately selected depending on the intended purpose without any limitation, but it is preferably 3 mPa·s or more and 20 mPa·s or less at 25°C, and 6 mPa·s or more and 12 mPa·s or less. Is more preferable.
When the viscosity is 3 mPa·s or more and 20 mPa·s or less, excellent ejection of the first liquid can be performed during three-dimensional modeling.
The viscosity can be measured in a 25° C. environment using, for example, a rotational viscometer (VISCOMATE VM-150III, manufactured by Toki Sangyo Co., Ltd.).

<Second step and second means>
The second step is a step of curing the film formed in the first step, and can be performed by the second means.

Examples of means for curing the film as the second means include an ultraviolet (UV) irradiation lamp and an electron beam. The means for curing the film is preferably equipped with a mechanism for removing ozone.
Examples of the type of the ultraviolet (UV) irradiation lamp include a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide, and an ultraviolet light emitting diode (UV-LED).
The ultra-high pressure mercury lamp is a point light source, but the DeepUV type, which has a high light utilization efficiency in combination with an optical system, can irradiate in a short wavelength region.
Since the metal halide has a wide wavelength region, it is effective as a coloring matter, and halides of metals such as Pb, Sn, and Fe are used, and can be selected according to the absorption spectrum of the photopolymerization initiator. The lamp used for curing is not particularly limited and may be appropriately selected depending on the purpose. For example, commercially available lamps such as H lamp, D lamp or V lamp manufactured by Fusion System Co., Ltd. Can be used.
The emission wavelength of the ultraviolet light emitting diode is not particularly limited and can be appropriately selected depending on the purpose. Generally, there are 365 nm, 375 nm, 385 nm, 395 nm, and 405 nm, but there are three-dimensional molded objects. Considering the influence of color, short-wavelength light emission is more advantageous so that the absorption of the polymerization initiator is increased.
The ultraviolet light emitting diode (UV-LED) has a smaller thermal energy applied to the film at the time of curing as compared with a commonly used ultraviolet irradiation lamp (for example, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp), an electron beam, and the like. Thermal damage to the membrane is reduced.

The film after curing is an organic-inorganic composite hydrogel in which water and a component soluble in the water are contained in a three-dimensional network structure formed by combining a water-soluble organic polymer and a layered mineral. Is preferred.
The organic-inorganic composite hydrogel has improved extensibility and can be peeled as a unit without breaking, and the treatment after modeling is significantly simplified.

<Third step and third means>
The third step is a step of smoothing the film cured in the second step, and can be performed by the third means.
The third means is appropriately selected depending on the intended purpose without any limitation, and examples thereof include a roller and a blade.

-Roller-
The shape, structure, size, material, etc. of the roller are not particularly limited and may be appropriately selected depending on the purpose. Examples of the shape include a cylindrical solid body and a hollow interior. The structure may be a single-layer structure or a laminated structure, and the size may be appropriately selected according to the size of the three-dimensional model or the like. can do. Examples of the material include resin, rubber, metal, and combinations thereof.
As the roller, a rubber roller having a cored bar and a rubber layer on the cored bar, a rubber roller composed only of rubber without the cored bar, a core material, and a foam layer formed on the outer periphery of the core material. And a foaming roller, a metal roller, or the like.

-Blade-
The shape, structure, size, material, etc. of the blade are not particularly limited and may be appropriately selected according to the purpose. Examples of the shape include a flat plate shape, a strip shape, and a sheet shape. The structure may be a single-layer structure or a laminated structure, and the size can be appropriately selected according to the size of the three-dimensional model or the like. .. Examples of the material include metal, plastic, rubber, and combinations thereof.
Examples of the blade include a support member and an elastic member partially fixed to the support member and having a free end, an elastic member only, and a doctor blade.

The film formed in the first step and cured in the second step does not always have the target film thickness (layer thickness) in all regions. That is, in the case of the inkjet method, there may be ejection failure, and in both the inkjet method and the dispenser method, a step difference between dots may occur, which may be insufficient for forming a highly accurate three-dimensional object.
To compensate for this, for example, mechanical smoothing (leveling) immediately after forming a layer, mechanical scraping, detection of smoothness, and deposition of the next layer at the dot level It is conceivable to adjust it with.
The hydrogel used in the present invention has a relatively soft hardness because the target three-dimensional model is an organ model such as an internal organ. Therefore, in smoothing, a smoothing method of mechanically smoothing immediately after forming the layer can be effectively used.
Examples of the method of mechanically smoothing include a method of smoothing with a blade-shaped smoothing member and a method of smoothing with a roller-shaped smoothing member.
When the roller-shaped smoothing member is used, the smoothing effect is more effectively exhibited when the roller is rotated in the reverse direction with respect to the operation direction.
The blade-shaped smoothing member is more effective than the roller-shaped smoothing member in the case where the surface of the molded body is shaved and smoothed.

<Other steps and other means>
The other steps are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a peeling step, a step of polishing a shaped body, and a step of cleaning a shaped body. be able to.

In the method for producing a three-dimensional molded object of the first aspect, each of the above steps is repeated a plurality of times. The number of repetitions varies depending on the size, shape, structure, etc. of the three-dimensional object to be produced, and cannot be specified unconditionally. Since it is possible to perform modeling without doing so, it is necessary to repeatedly stack the three-dimensional modeled object to be manufactured by the height.

A method for manufacturing a three-dimensional object according to a second aspect of the present invention includes the first step, the fourth step, the fifth step, and the sixth step, and includes the seventh step. Preferably, it further comprises other steps, if necessary.
An apparatus for manufacturing a three-dimensional object according to a second aspect of the present invention includes the first means, the fourth means, the fifth means, and the sixth means, and the seventh means. It is preferable to have, and if necessary, other means.

<Fourth step and fourth means>
The fourth step is a step of applying a second liquid containing at least a curable material to a position different from that of the first liquid to form a film, and can be implemented by the fourth means.
The means for applying the second liquid as the fourth means is the same as the first means in the manufacturing apparatus for a three-dimensional structure according to the first embodiment, and therefore the description thereof will be omitted.

The “position different from the first liquid” means that the application position of the second liquid and the application position of the first liquid do not overlap, and the application position of the second liquid and the first position The liquid application position may be adjacent. Since the second liquid has a different composition from the first liquid and is difficult to mix, even when the second liquid and the first liquid are adjacent to each other, the boundary between the two becomes clear after curing.

<<Second liquid>>
The second liquid is a liquid that serves as a hard molded body for supporting a molded body made of a hydrogel (soft body) (also referred to as "liquid material for hard molded body").
The second liquid contains at least a curable material and, if necessary, further contains other components.

-Curable material-
The curable material is preferably a compound that causes a polymerization reaction to be cured by irradiation with active energy rays (ultraviolet rays, electron beams, etc.), heating, and the like, and examples thereof include active energy ray curable compounds and photopolymerizable prepolymers. , Emulsion type photocurable resins, thermosetting compounds and the like. Among these, materials that are liquid at room temperature are preferable from the viewpoint of preventing nozzle clogging.

The active energy ray-curable compound is a compound that undergoes radical polymerization or cationic polymerization upon irradiation with active energy rays.
Examples of the compound capable of radical polymerization include compounds having an ethylenically unsaturated group.
Examples of the compound that undergoes cationic polymerization include compounds having an alicyclic epoxy group or an oxetane ring.

The active energy ray-curable compound is a monomer having a relatively low viscosity having an unsaturated double bond capable of radical polymerization in the molecular structure, and for example, a monofunctional 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, tetrahydro Furfuryl (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, bifunctional tripropylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol hydroxypivalate 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), 1,6-hexanediol 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 pentyl glycol di(meth)acrylate, ethoxy modified bisphenol A di(meth)acrylate Polyethylene glycol 200 di(meth)acrylate, polyethylene glycol 400 di(meth)acrylate, polyfunctional trimethylolpropane tri(meth)acrylate (TMPTA), pentaerythritol tri(meth)acrylate (PETA), dipentaerythritol hexa (Meth)acrylate (DPHA), Realyl 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, Penta (meth) acrylate ester etc. are mentioned. These may be used alone or in combination of two or more.

Examples of commercially available active energy ray-curable compounds include KAYARAD TC-110S, KAYARAD R-128H, KAYARAD R-526, KAYARAD NPGDA, KAYARAD PEG400DA, KAYARAD MANDA, KAYARAD R-167, KAYARAD HAR-AD, HX-220. HX-620, KAYARAD R-551, KAYARAD R-712, KAYARAD R-604, KAYARAD R-684, KAYARAD GPO, KAYARAD TMPTA, KAYARAD THE-330, KAYAARAD TPA-320, KAYAPARK TARA-AYA, TPA-320, KAYAPARADA TAPAATAAD. KAYARADRP-1040, KAYARAD T-1420, KAYARAD DPHA, KAYARAD DPHA-2C, KAYARAD D-310, KAYARAD D-330, KAYARAD DPCA-20, KAYARAD DPCA-30, KAYARAD DPCA-60, KAYARAD DPCA-120, KAYARAD DN- 0075, KAYARAD DN-2475, KAYAMER PM-2, KAYAMER PM-21, KS series HDDA, TPGDA, TMPTA, SR series 256, 257, 285, 335, 339A, 395, 440, 495, 504, 111, 212, 213. , 230, 259, 268, 272, 344, 349, 601, 602, 610, 9003, 368, 415, 444, 454, 492, 499, 502, 9020, 9035, 295, 355, 399E494, 9041203, 208, 242. 313, 604, 205, 206, 209, 210, 214, 231E239, 248, 252, 297, 348, 365C, 480, 9036, 350 (manufactured by Nippon Kayaku Co., Ltd.), beam set 770 (Arakawa Chemical Industry Co., Ltd.) (Made by a corporation). These may be used alone or in combination of two or more.

As the photopolymerizable prepolymer, a photopolymerizable prepolymer used for producing an ultraviolet curable resin can be used. Examples of the photopolymerizable prepolymer include polyester resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, ether resins, and acrylates or methacrylates of polyhydric alcohols.

Examples of the emulsion-type photocurable resin include polyester (meth)acrylate, bisphenol-based epoxy (meth)acrylate, bisphenol A-based epoxy (meth)acrylate, propylene oxide-modified bisphenol A-based epoxy (meth)acrylate, and alkali Soluble epoxy (meth)acrylate, acrylic modified epoxy (meth)acrylate, phosphoric acid modified epoxy (meth)acrylate, polycarbonate urethane (meth)acrylate, polyester urethane (meth)acrylate, alicyclic urethane (meth)acrylate, fat Group urethane (meth)acrylate, polybutadiene (meth)acrylate, polystyryl (meth)acrylate and the like can be mentioned.

Examples of commercially available emulsion-type photocurable resins include, for example, Diamond Beam UK6105, Diamond Beam UK6038, Diamond Beam UK6055, Diamond Beam UK6063, Diamond Beam UK4203 (above, manufactured by Mitsubishi Rayon Co., Ltd.), Orestar Ra1574 (Mitsui). Chemical Co., Ltd.), KAYARAD UX series 2201, 2301, 3204, 3301, 4101, 6101, 7101, 8101, KAYARAD R&EX series, 011, 300, 130, 190, 2320, 205, 131, 146, 280, KAYARAD MAX series. 1100, 2100, 2101, 2102, 2203, 2104, 3100, 3101, 3510, 3661 (above, manufactured by Nippon Kayaku Co., Ltd.), beam sets 700, 710, 720, 750, 502H, 504H, 505A-6, 510. 550B, 551B, 575, 261, 265, 267, 259, 255, 271, 243, 101, 102, 115, 207TS, 575CB, AQ-7, AQ-9, AQ-11, EM-90, EM-92. (Above, manufactured by Arakawa Chemical Industry Co., Ltd.), 0304TB, 0401TA, 0403KA, 0404EA, 0404TB, 0502TI0502TC, 102A, 103A, 103B, 104A, 1312MA, 1403EA, 1422TM, 1428TA, 1438MG, 1551MB, IBR-305, 1FC-507. 1SM-012, 1AN-202, 1ST-307, 1AP-201, 1PA-202, 1XV-003, 1KW-430, 1KW-501, 4501TA, 4502MA, 4503MX, 4517MB, 4512MA, 4523TI, 4537MA, 4557MB, 6501MA. , 6508MG, 6513MG, 6416MA, 6421MA, 6560MA, 6614MA, 717-1, 856-5, QT701-45, 6522MA, 6479MA, 6519MB, 6535MA, 724-65A, 824-65, 6540MA, 6RI-350, 6TH-419. , 6HB-601, 6543MB, 6AZ-162, 6AZ-309, 6AZ-215, 6544MA, 6AT-203B, 6BF-203, 6AT-113, 6HY316, 6RL-505, 7408MA, 7501TE, 7511MA, 7505TC, 7529MA, MT408. -13, MT408-15, MT408-42, 7CJ-601, 7PN-302, 7541MB, 7RZ-011, 7613MA, 8DL-100, 8AZ-103, 5YD-420, 9504MNS, Akrit WEM-202U, 030U, 321U, 306U, 162, WBR-183U. , 601U, 401U, 3DR-057, 829, 828 (all manufactured by Taisei Kako Co., Ltd.) and the like.

The content of the curable material is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.001% by mass to 1% by mass with respect to the total amount of the second liquid.

-Other ingredients-
The other components are not particularly limited and may be appropriately selected depending on the purpose, for example, a polymerization initiator, a colorant, a water-soluble resin, water, a low boiling point alcohol, a surfactant, a viscosity modifier, Examples thereof include adhesion promoters, antioxidants, antioxidants, crosslinking accelerators, ultraviolet absorbers, plasticizers, preservatives and dispersants.

---Polymerization initiator---
Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator.

--- Thermal polymerization initiator ---
The thermal polymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include azo initiators, peroxide initiators, persulfate initiators and redox (redox) initiators. And so on.

--- Photopolymerization initiator ---
As the photopolymerization initiator, any substance that generates radicals upon irradiation with light (especially ultraviolet rays having a wavelength of 220 nm to 400 nm) can be used.
Examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, benzophenone, 2-chlorobenzophenone, p,p'-dichlorobenzophenone, p,p-bisdiethylaminobenzophenone, Michler's ketone. , Benzyl, 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, methylbenzoylformate, 1-hydroxycyclohexylphenylketone, azobisisobutyronitrile , Benzoyl peroxide, di-tert-butyl peroxide and the like. These may be used alone or in combination of two or more.

The content of the polymerization initiator is appropriately selected depending on the intended purpose without any limitation, but it is preferably 0.01% by mass or more and 3% by mass or less based on the total amount of the curable material.

A sensitizer is used for the purpose of preventing a decrease in the curing speed due to the light (especially ultraviolet light) being absorbed or hidden by the pigment of the second liquid when irradiated with light (especially ultraviolet light). You can also do it.
Examples of the sensitizer include aliphatic amines, amines having an aromatic group, cyclic amine compounds such as piperidine; urea compounds such as o-tolylthiourea; sodium diethylthiophosphate and soluble salts of aromatic sulfinic acid. Sulfur compounds such as; N,N′-disubstituted-p-aminobenzonitriles and other nitrile compounds; Tri-n-butylphosphine, sodium diethyldithiophosfeed and other phosphorus compounds; Michler's ketone, N-nitrosohydroxylamine derivatives, oxazolidine Examples thereof include compounds, tetrahydro-1,3-oxazine compounds, formaldehyde, and nitrogen compounds such as condensates of acetaldehyde and diamine. These may be used alone or in combination of two or more.

--- Colorant ---
As the colorant, dyes and pigments that are dissolved or stably dispersed in the second liquid and have excellent thermal stability are suitable. Among these, a soluble dye (Solvent Dye) is preferable. Further, it is possible to mix two or more kinds of colorants in a timely manner for the purpose of adjusting color.

-Physical properties of the second liquid-
The surface tension of the second liquid is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 20 mN/m or more and 45 mN/m or less, and 25 mN/m or more and 34 mN/m or less. More preferable.
When the surface tension is 20 mN/m or more and 45 mN/m or less, excellent ejection of the second liquid can be performed during three-dimensional modeling.
The surface tension can be measured using, for example, a surface tensiometer (automatic contact angle meter DM-701, manufactured by Kyowa Interface Science Co., Ltd.).
The viscosity of the second liquid is appropriately selected depending on the intended purpose without any limitation, but it is preferably 3 mPa·s or more and 20 mPa·s or less at 25°C, and 6 mPa·s or more and 12 mPa·s or less. Is more preferable.
When the viscosity is 3 mPa·s or more and 20 mPa·s or less, the second liquid can be excellently ejected at the time of three-dimensional modeling.
The viscosity can be measured in a 25° C. environment using, for example, a rotational viscometer (VISCOMATE VM-150III, manufactured by Toki Sangyo Co., Ltd.).

<Fifth Step and Fifth Means>
The fifth step is a step of curing the films respectively formed in the first step and the fourth step, and can be implemented by the fifth means.
Since the fifth step and the fifth means are the same as the second step and the second means in the method for manufacturing a three-dimensional structure and the manufacturing apparatus therefor of the first embodiment, the description thereof will be omitted. Omit it.
The curing of the film formed in the first step and the curing of the film formed in the fourth step may be performed simultaneously or separately.
The film after curing is an organic-inorganic composite hydrogel in which water and a component soluble in the water are contained in a three-dimensional network structure formed by combining a water-soluble organic polymer and a layered mineral. That is, when the support is removed after modeling, it is preferably used for spontaneous peeling by simply shrinking the support by drying.
The organic-inorganic composite hydrogel has improved extensibility and can be peeled together without breakage, and the treatment after three-dimensional modeling is significantly simplified.

<Sixth step and sixth means>
The sixth step is a step of smoothing the film cured in the fifth step, and can be performed by the sixth means.
Since the sixth step and the sixth means are the same as the third step and the third means in the method for manufacturing a three-dimensional object and the manufacturing apparatus therefor of the first embodiment, the description thereof will be omitted. Omit it.

<Seventh step and seventh means>
The seventh step is a step of peeling off a portion made of the hydrogel formed of the hydrogel precursor and a portion made of the polymer formed of the curable material, and is performed by the seventh means. be able to.
The seventh means is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include various peeling devices.

The rubber hardness of the hydrogel portion is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 6 or more and 60 or less, and more preferably 8 or more and 20 or less.
When the rubber hardness is 6 or more and 60 or less, the shape is not deformed during the three-dimensional modeling, and the peeling after the three-dimensional modeling can be favorably performed.
The rubber hardness can be measured by a method conforming to ISO7691 (type A), and can be measured using, for example, a durometer (GS-718N manufactured by Teclock Co., Ltd.).
The portion made of the hydrogel and the portion made of the polymer can be peeled off by drying shrinkage.
The drying shrinkage can be performed by various methods such as a method of leaving it in an atmosphere of 50° C. and a method of reducing the pressure.

<Other steps and other means>
The other steps are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a discharge stabilization step, a molded body cleaning step, and a molded body polishing step. The cleaning can be performed by a cleaning means for the molded body, a polishing means for the molded body, or the like.

-Discharge stabilization process and discharge stabilization means-
When an inkjet head is used as a means for ejecting liquid, drying of the nozzles during non-ejection is a major issue for stable operation.
For this reason, the ejection stabilizing step and the ejection stabilizing means cover (1) the ejection port with a member having a shape that covers at least the tip of the head when continuous ejection from the inkjet head is not performed for a long time. To prevent the tip of the ejection port from drying, (2) to discharge the film formed by suctioning the film formed by the viscosity of the internal liquid near the ejection port increasing or the drying, (3) the ejection port, Alternatively, the ejection stable state can be maintained for a long time by wiping the ejection port and its periphery.
These are extremely important in the step of forming a three-dimensional object requiring continuous discharge for a long time of 24 hours or more, especially when a liquid containing a low boiling point solvent such as water is used in forming a soft material. is important.

---Capping process---
In the capping step, the inkjet head moves to the cap portion and comes into contact with the cap when a suction instruction is given after the discharging operation is completed. After the cap contact is completed, the pump starts the suction operation, and the liquid is discharged from all the discharge ports including the defective discharge portion. After the suction operation is completed, the inkjet head moves along the wiping member, and the capping process is completed.

---Discharge failure recovery process---
In the ejection failure recovery step, the inkjet head is then moved to the ejection position to restart the ejection operation. When the ejection is completed and the modeling is completed, the ejection defective recovery step is completed by moving to the cap contact position again.
When manufacturing a large three-dimensional object, it is necessary to perform continuous ejection for a long period of time, so it is preferable that the ejection failure recovery step be performed regularly.
The timing of recovery from ejection failure is not particularly limited and can be appropriately selected according to the purpose. However, from the viewpoint of recovery from ejection failure, it is preferable to periodically perform the operation every continuous operation within 2 hours. ..

In the method for manufacturing a three-dimensional molded object according to the second aspect, the above steps are repeated a plurality of times. The number of repetitions depends on the size, shape, structure, etc. of the three-dimensional object to be produced and cannot be specified in a general manner. However, if the thickness per layer is in the range of 10 μm to 50 μm, peeling is performed accurately. Since it is possible to form without a problem, it is necessary to repeat stacking for the height of the three-dimensional model to be manufactured.

In the method for producing a three-dimensional molded object according to the second aspect, in the case of manufacturing a soft molded body of a hydrogel formed from a hydrogel precursor, water as a liquid forming the soft molded body, and The first liquid containing at least the hydrogel precursor is used, and the second liquid containing at least the curable material is used as the liquid forming the support.
On the contrary, when it is desired to manufacture a rigid molded body, the second liquid containing at least a curable material is used as the liquid forming the three-dimensional molded body, and water and hydrogel are used as the liquid forming the support. A first liquid containing at least a precursor is used.
Therefore, in the method for manufacturing a three-dimensional molded object according to the second aspect, it is possible to make different models by simply changing the liquid to be applied depending on the hardness of the desired molded object. Further, in any case, it is possible to peel the film very easily due to the difference in hardness between the support and the shaped body.
Further, which of the first step and the third step may be performed first, it is preferable that the third step is performed first because the support can be formed first.

As described above, in the method for producing a three-dimensional object according to the present invention, the liquid is ejected from the pores such as the inkjet method and the dispenser method so that the image is formed layer by layer and cured. The first liquid and the second liquid are in an incompatible state in which the first liquid and the second liquid are intimately separated from each other and are immiscible.
In the conventional modeling method, the contact portion of the first liquid and the second liquid are compatible with each other, and the boundary becomes unclear during photocuring. As a result, fine irregularities remain on the surface of the molded body, but in the method for producing a three-dimensional molded article of the present invention, the first liquid and the second liquid are incompatible with each other. The boundary of becomes clear. Furthermore, due to the difference in hardness between the obtained shaped body and the support, the peelability is improved. Thereby, the surface smoothness of the molded body is improved, and the polishing step after three-dimensional modeling can be omitted or significantly reduced.

Hereinafter, specific embodiments of the method for producing a three-dimensional object and the apparatus for producing a three-dimensional object according to the present invention will be described.
A liquid material for a soft molded body was used as the first liquid, and a liquid material for a hard molded body was used as the second liquid to obtain a molded article of a soft hydrogel.
As described above, in order to obtain a soft three-dimensional molded object, the liquid material for the soft molded body is arranged in the molded body portion, and the liquid material for the hard molded body is arranged in the support body portion. In order to obtain a hard three-dimensional molded object, conversely, the liquid material for the hard molded body is arranged in the molded body portion and the liquid material for the soft molded body is arranged in the support portion.
As a method of applying the liquid, an inkjet method or a dispenser method can be applied as long as it can apply the liquid droplets to a desired place with appropriate accuracy. Since the embodiments are almost the same in all cases, the following description will focus on a mode using an inkjet method as a liquid applying method.

First, surface data or solid data of a three-dimensional shape designed by three-dimensional CAD or a three-dimensional shape captured by a three-dimensional scanner or a digitizer is converted into an STL format and input to a three-dimensional object manufacturing apparatus.

Based on the input data, the modeling direction of the three-dimensional shape to be modeled is determined. The molding direction is not particularly limited, but the direction in which the Z direction (height direction) is the lowest is usually selected.

After the modeling direction is determined, the projected area of the three-dimensional shape on the XY plane, the XZ plane, and the YZ plane is obtained. In order to reinforce the obtained block shape, each surface other than the upper surface of the XY plane is moved to an appropriate amount outside. The amount to be moved is not particularly limited and is about 1 mm to 10 mm, although it varies depending on the shape and size and the liquid material used. With this, the block shape that confine the shape to be formed (the upper surface is open) is specified.

This block shape is sliced in the Z direction with a single layer thickness. The thickness of the single layer differs depending on the material used and cannot be specified unconditionally, but is preferably 10 μm or more and 50 μm or less.
When there is only one three-dimensional object to be modeled, the block shape is arranged so as to come to the center of the Z stage (a table on which the model object descends by one layer for each layer model is placed). When a plurality of blocks are formed at the same time, the block shapes are arranged on the Z stage, but the block shapes can be stacked. The block shape, the sliced data (slice data: contour line data) and the arrangement on the Z stage can be automatically created by designating the liquid material to be used.

Next, a modeling step is performed. Soft molding by inner/outer judgment (determining whether to inject liquid material for soft molding or liquid material for hard molding at the position on the contour) based on the outermost contour of the sliced data The position where the body liquid material is ejected and the position where the hard molded body liquid material is ejected are controlled.

As for the order of injection, the liquid material for the hard molded body that forms the support layer is ejected, and then the liquid material for the soft molded body that forms the shaped body layer is ejected.

When sprayed in this order, the support forms a reservoir such as a groove or weir first, and the liquid material for the soft molded body is sprayed into the reservoir, so that the liquid material for the soft molded body is ejected at room temperature. Even if a liquid material is used, there is no fear of "dripping", and photocurable resins, thermosetting resins, etc. can be widely used.

Further, in order to further shorten the molding time, it is preferable to jet and laminate the liquid material for the soft molded body and the liquid material for the hard molded body in each of the forward path and the return path of the integrated inkjet head.

Furthermore, high-speed modeling is possible by placing an active energy ray irradiator adjacent to an inkjet head that ejects the liquid material for a soft compact.
Further, in order to smooth the three-dimensionally formed layer, the smoothing treatment is performed immediately after the curing treatment.
The smoothing treatment is to smooth the surface of the cured film by using a smoothing member such as a roller or a blade. As a result, the accuracy of each layer is improved, and the entire three-dimensional object can be accurately manufactured.
At this time, in order to shorten the stacking time and improve the smoothness of the layers, it is preferable to dispose the smoothing member adjacent to the ultraviolet irradiator.

FIG. 2 is a schematic diagram showing an example of a process for producing a three-dimensional object in the method for producing a three-dimensional object of the present invention using the apparatus for producing a three-dimensional object of the present invention.
The manufacturing apparatus 10 for a three-dimensional object uses a head unit in which inkjet heads are arranged to supply liquid material for a soft molded body from the liquid material ejecting head unit 11 for a molded body and liquid material ejecting head units for a support body 12 and 13. The liquid material for the hard molded body is jetted, and the liquid material for the soft molded body is laminated while being cured by the adjacent UV irradiators 14 and 15.
That is, a liquid material for a hard molded body is jetted from an inkjet head (liquid material jetting head units 12, 13 for a support) and solidified to form a first support layer having a reservoir, and the first support body is formed. A liquid material for a soft molded body is jetted from an inkjet head (a liquid material jetting head unit 11 for a molded body) to the reservoir portion of the layer, and the liquid material for a soft molded body is irradiated with active energy rays to be cured, and then cured. The film is subjected to a smoothing treatment using a smoothing member (rollers 20, 21) to form a first shaped body layer.
Next, a molten liquid material for a hard molded body is jetted and solidified on the first support layer to laminate a second support layer having a reservoir, and the reservoir of the second support layer is laminated. The liquid material for a soft molded body is jetted onto the surface of the molded body, and the liquid material for a soft molded body is irradiated with an active energy ray to laminate the second molded body layer on the first molded body layer, and further smoothing treatment is performed. Then, the three-dimensional three-dimensional object 19 is manufactured.

When the multi-head unit moves in the direction of the arrow A, basically, the support material 18 and the modeling object are formed using the liquid material ejecting head unit 12 for the supporting body, the liquid material ejecting head unit 11 for the modeling object, and the ultraviolet irradiator 15. 19 is formed on the molded body supporting substrate 16. At the same time, the roller-shaped smoothing member 21 smoothes the support 18 and the shaped body 19. The liquid material jetting head unit 13 for the support and the ultraviolet irradiator 14 may be used supplementarily.
When a roller-shaped smoothing member is used, the smoothing effect is more effectively exhibited when the roller is rotated in the direction in which the roller is reversed with respect to the operation direction.

When the multi-head unit moves in the direction of the arrow B, the support 18, the liquid material jetting head unit 13 for the support body, the liquid material jetting head unit 11 for the modeling body, and the ultraviolet irradiator 14 are basically used. The molded body 19 is formed on the molded body supporting substrate 16. At the same time, the roller-shaped smoothing member 20 smoothes the support 18 and the shaped body 19. The liquid material ejecting head unit 12 for the support and the ultraviolet irradiator 15 may be used supplementarily.

Further, in order to keep the gap between the liquid material ejecting head units 11, 12, 13 and the ultraviolet irradiation devices 14, 15 and the shaped body 19 and the support 18 constant, the stage 17 is lowered and laminated according to the number of lamination. ..

FIG. 3 is a schematic diagram showing another example of a process for producing a three-dimensional object in the method for producing a three-dimensional object according to the present invention using the apparatus for producing a three-dimensional object according to the present invention. Specifically, the roller-shaped smoothing members 20 and 21 of FIG. 2 are changed to blade-shaped smoothing members 22 and 23. The blade-shaped smoothing member of FIG. 3 can be more effectively used when the surface of the molded body is shaved and smoothed than the roller-shaped smoothing member used in FIG.

FIG. 4 is a schematic view showing another example of a three-dimensional structure manufacturing process having a configuration capable of improving the smoothness of each layer as compared with FIG. The basic process is the same as that of FIG. 2, except that the ultraviolet irradiators 14 and 15 are arranged between the liquid material ejecting head 11 for modeling body and the liquid material ejecting heads 12 and 13 for support. ..
Further, in the three-dimensional object manufacturing apparatus 10 of the present system, the ultraviolet irradiators 14 and 15 are used when moving in any of the directions of arrows A and B, and the heat generated by the irradiation of the ultraviolet rays causes the laminated hard molding. The surface of the body liquid material is smoothed, and as a result, the dimensional stability of the shaped body is improved.

In addition, a liquid recovery mechanism, a recycling mechanism, or the like can be added to the three-dimensional model device 10. A blade for removing the liquid material adhering to the nozzle surface or a non-ejection nozzle detection mechanism may be provided. Furthermore, it is also preferable to control the environmental temperature in the manufacturing apparatus of the three-dimensional molded object at the time of three-dimensional molding.

<Liquid set for 3D modeling>
The three-dimensional modeling liquid set used in the present invention contains the first liquid and the second liquid, and further contains other components as necessary.
The liquid set for three-dimensional modeling can be suitably used for manufacturing various three-dimensional molded objects, and in particular, can be preferably used for manufacturing complicated and fine three-dimensional molded objects represented by organ models and the like.

<Three-dimensional object>
The three-dimensional molded article used in the present invention comprises a hydrogel formed from a hydrogel precursor, and the rubber hardness of the hydrogel is 6 or more and 60 or less, preferably 8 or more and 20 or less.
When the rubber hardness is 6 or more and 60 or less, elasticity and strength required for an organ model can be obtained.
The rubber hardness can be measured, for example, by a method based on ISO7691 (type A).

The hydrogel is preferably a hydrogel in which water is contained in a three-dimensional network structure formed by combining a water-soluble organic polymer and a single layer dispersion of a layered mineral.
Examples of the water-soluble organic polymer include organic polymers having an amide group, an amino group, a hydroxyl group, a tetramethylammonium group, a silanol group, an epoxy group and the like.
The water-soluble organic polymer is an advantageous component for maintaining the strength of an aqueous gel.
The organic polymer may be a homopolymer (homopolymer), a heteropolymer (copolymer), or may be modified, as long as it exhibits water solubility. The functional group (1) may be introduced, or the salt may be in the form of a salt, but a homopolymer is preferable.
The water-solubility of the water-soluble organic polymer means, for example, when 100 g of water at 30° C. is mixed with 1 g of the organic polymer and stirred, 90% by mass or more thereof is dissolved.
The three-dimensional model is preferably used as an organ model. The above-mentioned organ model is particularly suitable as an organ model for practicing procedures, because the touch and sharpness of the organ are very close to those of the desired organ, and incision is possible with a surgical knife.

Examples of the present invention will be described below, but the present invention is not limited to these examples.
Specific examples of three-dimensional modeling in which the liquid material for the soft molded body as the first liquid and the liquid material for the hard molded body as the second liquid are laminated one by one will be described below.

(Example 1)
-Preparation of Second Liquid (Liquid Material for Hard Molding)-
10 parts by mass of urethane acrylate (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Diabeam UK6038) as a curable material, neopentyl glycol hydroxypivalate ester di(meth)acrylate as a curable material (manufactured by Nippon Kayaku Co., Ltd., trade name: 90 parts by mass of KAYARAD MANDA, 3 parts by mass of a photopolymerization initiator (manufactured by BASF, trade name: Irgacure 184), and 2 parts by mass of a blue pigment (manufactured by Toyo Ink Co., Ltd., trade name: Lionol Blue 7400G) as a colorant. A total of 300 g was dispersed using a homogenizer (HG30 manufactured by Hitachi Koki Co., Ltd.) at a rotation speed of 2,000 rpm until a homogeneous mixture was obtained. Subsequently, filtration was performed to remove impurities and the like, and finally vacuum deaeration was performed for 10 minutes to obtain a uniform liquid material for a hard molded body.
The surface tension and the viscosity of the obtained liquid material for a hard molded body were measured as follows. The surface tension was 27.1 mN/m, and the viscosity was 10.1 mPa·s at 25°C.

[Measurement of surface tension]
The surface tension of the obtained liquid material for a hard compact was measured by a hanging drop method using a surface tension meter (automatic contact angle meter DM-701, manufactured by Kyowa Interface Science Co., Ltd.).

[Measurement of viscosity]
The obtained liquid material for a hard molded body was measured with a rotational viscometer (VISCOMATE VM-150III, manufactured by Toki Sangyo Co., Ltd.) in an environment of 25.0°C.

<Manufacture of first liquid (liquid material for soft molded body)>
Ion-exchanged water that had been degassed under reduced pressure for 10 minutes was used as pure water.

-Preparation of initiator liquid-
(A) As the initiator liquid 1, 2 parts by mass of a photopolymerization initiator (Irgacure 184, manufactured by BASF) was dissolved in 98 parts by mass of methanol to prepare a solution.

(B) As the initiator liquid 2, 2 parts by mass of sodium peroxodisulfate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 98 parts by mass of pure water to prepare an aqueous solution.

-Preparation of liquid material for soft compact-
First, while stirring the pure water 195 parts by mass, as a water-swellable layered clay mineral _{[Mg 5.34 Li 0.66 Si 8 O} 20 (OH) 4] Na - 0.66 synthetic hectorite having a composition of ( 8 parts by mass of Laponite XLG (manufactured by Rockwood) was added little by little and stirred to prepare a dispersion liquid.
Next, 20 parts by mass of N,N-dimethylacrylamide (DMA, manufactured by Wako Pure Chemical Industries, Ltd.) from which a polymerization inhibitor was removed by passing through a column of activated alumina was added to the obtained dispersion as a polymerizable monomer. .. Further, 0.2 part by mass of sodium dodecyl sulfate (manufactured by Wako Pure Chemical Industries, Ltd.) as a surfactant was added and mixed.
Next, while cooling in an ice bath, 0.5 parts by mass of the (A) initiator liquid 1 and 5 parts by mass of the (B) initiator liquid 2 were added, and after stirring and mixing, deaeration under reduced pressure was performed. It was carried out for 10 minutes. Then, filtration was performed to remove impurities and the like, and a homogeneous liquid material for a soft molded body was obtained.
The surface tension of the obtained liquid material for a soft molded body measured in the same manner as the liquid material for a hard molded body is 34.4 mN/m, and the viscosity measured in the same manner as the liquid material for a hard molded body is It was 10.1 mPa·s at 25.0°C.

<3D modeling>
The liquid material for the hard molded body and the liquid material for the soft molded body are filled in two tanks leading to an ink jet head (GEN4, manufactured by Ricoh Industry Co., Ltd.) of the manufacturing apparatus 10 for a three-dimensional structure illustrated in FIG. The liquid material for the hard molded body and the liquid material for the soft molded body were respectively ejected from the inkjet head to form a film. The liquid material for the hard molded body and the liquid material for the soft molded body were ejected at different positions.
Next, after irradiating the film with a light amount of 350 mJ/cm ² by an ultraviolet irradiation device (SPOT CURE SP5-250DB, manufactured by Ushio Inc.) 14, 15 to cure the film, the cured film is applied. The rollers 20 and 21 were subjected to smoothing treatment to form a three-dimensional molded object and a support.
As the roller, a metal roller made of an aluminum alloy having a diameter of 25 mm, the surface of which was anodized, was used.

Next, various characteristics of the obtained three-dimensional molded item were evaluated as follows. The results are shown in Table 3.

<Formability of 3D objects>
As shown in FIG. 5, the staircase-shaped molded body 30 and the supports 31 and 32 covering the staircase-shaped molded body 30 were three-dimensionally modeled using the three-dimensional modeled object manufacturing apparatus shown in FIG. The moldability of the three-dimensional molded item at this time was evaluated based on the following criteria.
[Evaluation criteria]
○: Targeted modeling was possible (good)
×: The target modeling could not be performed (defective)

<Measurement of “horizontal error” and “vertical error” of model>
Regarding the “horizontal error” and “vertical error” of the obtained model 30, as shown in FIG. 7, the horizontal and vertical dimensions of the model 30 were measured at each of 10 points with a caliper. Variations at 10 points were determined as follows and evaluated according to the following criteria.
-10 variations
The lengths in the horizontal direction and the vertical direction of the modeled body 30 shown in FIG. 7 are measured with a caliper at 10 points, and the obtained measured values at 10 points and the input signal for modeling (the target length in the horizontal direction or the vertical direction). The maximum value and the minimum value of the error from the target length) were obtained. The larger of the absolute values is selected from the maximum value and the minimum value of the obtained errors, and the absolute value of the selected errors is divided by the input signal (horizontal target length or vertical target length). Then, the ratio (%) multiplied by 100 was obtained, and the variation was set at 10 points.
[Evaluation criteria]
⊚: Variation at 10 locations is less than 2% (good)
◯: Variation at 10 points is 2% or more and less than 5% (normal)
X: Variation in 10 locations is 5% or more (defective)

<Peeling off>
Immediately after modeling the three-dimensional model, the support 31 was pulled in the horizontal direction as shown in FIG. 6 and peeled off to obtain a model 30. The tensile peeling was evaluated based on the following criteria.
[Evaluation criteria]
⊚: The support was peeled off as a unit, and a shaped body was obtained without the need for subsequent treatment (good).
◯: Most of the support could be peeled off, and the part of the support that remained partially could be completely peeled off by simply rubbing with a brush (normal)
X: The support cannot be peeled off (defective)

<Peeling after drying>
After performing the tensile peeling test on one of the supports 31 shown in FIG. 6, the other support 32 is left at room temperature (25° C.) for 5 hours, and then a test of peeling the support 32 is performed. The peeling after drying was evaluated based on the standard.
[Evaluation criteria]
⊚: After peeling, the molded body and the support that had been dried and shrunk were completely separated, and the support could be peeled as a unit (good)
◯: Most of the support could be peeled off, and the part of the support that remained partially could be completely peeled off by simply rubbing with a brush (normal)
X: The support cannot be peeled off (defective)

<Surface property of the molded body after peeling>
The surface of the shaped body (interface with the support) 33 after the tensile peeling test was observed, and the surface property of the shaped body after peeling was evaluated based on the following criteria.
[Evaluation criteria]
◯: A smooth surface was obtained without any minute support remaining on the surface of the molded body (good).
X: The support remains, and a smooth surface cannot be obtained (defective)

<Rubber hardness of model>
Separately, the liquid material for a soft molded body is poured into a mold, and a lid is covered with glass to make a closed state, and a light amount of 350 mJ/cm ² with an ultraviolet irradiator (USHIO INC., SPOT CURE SP5-250DB) 14, 15 is used. Was irradiated and cured to prepare a cylindrical pellet-shaped sample piece (hydrogel, shaped body) having a diameter of 20 mm and a thickness of 4 mm.
The obtained sample piece was pressed with a durometer (GS-718N, manufactured by Teclock Co., Ltd.) into the center of the surface having a diameter of 20 mm, and the rubber hardness after 15 seconds was measured by a method according to ISO7691 (type A). The rubber hardness was 16.

(Example 2)
In the same manner as in Example 1 except that the content of the synthetic hectorite (Laponite XLG, manufactured by Nippon Silica Co., Ltd.) in the liquid material for a soft molded body was changed to 4 parts by mass to prepare a dispersion liquid. Then, a liquid material for a soft molded body was produced, and three-dimensional modeling was performed in the same manner as in Example 1.
With respect to the obtained liquid material for a soft molded body, the viscosity measured in the same manner as the liquid material for a hard molded body of Example 1 above was 6.8 mPa·s at 25.0° C., and the surface tension was the same as in Example 1. It was 0.4 mN/m.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Example 3)
Same as Example 1 except that the content of the synthetic hectorite (Laponite XLG, manufactured by Nippon Silica Co., Ltd.) in the liquid material for a flexible molded body was changed to 12 parts by mass to prepare a dispersion liquid. In the same manner as in Example 1, a liquid material for a soft molded body was produced, and three-dimensional modeling was performed.
With respect to the obtained liquid material for a soft molded body, the viscosity measured in the same manner as the liquid material for a hard molded body of Example 1 above was 17.6 mPa·s at 25.0° C., and the surface tension was the same as in Example 1. It was 0.4 mN/m.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Example 4)
In Example 1, except that the polymerizable monomer in the liquid material for a soft molded body was changed to N-isopropylacrylamide (IPMA manufactured by Wako Pure Chemical Industries, Ltd.), the liquid for a soft molded body was obtained. A material was produced and three-dimensional modeling was performed in the same manner as in Example 1.
With respect to the obtained liquid material for a soft molded body, the viscosity measured in the same manner as the liquid material for a hard molded body of Example 1 above was 10.3 mPa·s at 25.0° C., and the surface tension was the same as in Example 1. It was 0.4 mN/m.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Example 5)
Using the same liquid material for soft molding and liquid material for hard molding as in Example 1, three-dimensional modeling was performed in the same manner as in Example 1.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.
In Example 5, the peeling after drying was carried out by heating and drying at 50° C. for 2 hours to peel off, and the support was completely peeled off in about 10 minutes, which was good.

(Comparative Example 1)
In the same manner as in Example 1, except that a liquid material for a soft molded body was added with an equal amount of N,N′-methylenebisacrylamide (manufactured by Wako Pure Chemical Industries, Ltd.) instead of the synthetic hectorite. Then, a liquid material for a soft molded body was produced, and three-dimensional modeling was performed in the same manner as in Example 1. In Comparative Example 1, no hydrogel precursor was obtained and no hydrogel was obtained.
With respect to the obtained liquid material for a soft molded body, the viscosity measured in the same manner as the liquid material for a hard molded body of Example 1 was 8.0 mPa·s at 25.0° C., and the surface tension was the same as in Example 1. It was 0.4 mN/m.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.
In Comparative Example 1, it was found that a part of the molded body could not bear the weight of the support and was crushed during the three-dimensional molding, and the target molded body could not be obtained.

(Comparative example 2)
Three-dimensional modeling was performed in the same manner as in Example 1 except that smoothing treatment was not performed.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Example 6)
In Example 1, three-dimensional modeling was performed in the same manner as in Example 1 except that the manufacturing apparatus for the three-dimensional model shown in FIG. 3 was used during three-dimensional modeling.
A urethane resin blade (JIS-A hardness: 60 degrees) having a thickness of 2 mm was used as the blade.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.

(Example 7)
In Example 1, three-dimensional modeling was performed in the same manner as in Example 1 except that the three-dimensional model manufacturing apparatus shown in FIG.
As the roller, a metal roller made of an aluminum alloy having a diameter of 25 mm, the surface of which was anodized, was used.
Next, various properties of the obtained three-dimensional molded item were evaluated in the same manner as in Example 1. The results are shown in Table 3.

Next, details of the liquid material for the soft molded body and the liquid material for the hard molded body are summarized in Tables 1 and 2.

The details of the liquid material for soft moldings and the liquid material for hard moldings shown in Table 1 and Table 2 are as follows.
*Layered mineral XLG: [Mg _5.34 Li _0.66 Si ₈ O ₂₀ (OH) ₄ ]Na ^- _0.66 synthetic hectorite (Laponite XLG, manufactured by Rockwood).
*Polymerizable monomer DMA: N,N-dimethylacrylamide (manufactured by Wako Pure Chemical Industries, Ltd.)
*Polymerizable monomer IPAM: N-isopropylacrylamide (manufactured by Wako Pure Chemical Industries, Ltd.)
*Curable material UK6038: Urethane acrylate (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Diamond Beam UK6038)
*Curable material MANDA: neopentyl glycol hydroxypivalic acid ester di(meth)acrylate (manufactured by Nippon Kayaku Co., Ltd., trade name: KAYARAD MANDA)
*Photopolymerization initiator (BASF, Irgacure 184)
*Blue pigment: manufactured by Toyo Ink Co., Ltd., trade name: Lionol Blue 7400G

表３の結果から、実施例１から７は、比較例１に比べて造形体の成型性に優れ、比較例１及び２に比べて造形体の「水平方向の誤差」及び「垂直方向の誤差」のバラツキが小さいことがわかった。

From the results of Table 3, Examples 1 to 7 are excellent in moldability of the molded body as compared with Comparative Example 1, and have “horizontal error” and “vertical error” of the molded body as compared with Comparative Examples 1 and 2. It was found that there was little variation.

Aspects of the present invention are as follows, for example.
<1> A first step of applying a first liquid containing at least water and a hydrogel precursor to form a film,
A second step of curing the film formed in the first step,
A third step of smoothing the film cured in the second step,
This is a method for producing a three-dimensional molded item, which is characterized in that
<2> A first step of applying a first liquid containing at least water and a hydrogel precursor to form a film,
A fourth step of forming a film by applying a second liquid containing at least a curable material to a position different from the first liquid,
A fifth step of curing the films respectively formed in the first step and the fourth step,
A sixth step of smoothing the film cured in the fifth step,
This is a method for producing a three-dimensional molded item, which is characterized in that
<3> The method for producing a three-dimensional object according to any one of <1> to <2>, wherein the hydrogel precursor contains a water-dispersible mineral and a polymerizable monomer.
<4> The method for producing a three-dimensional object according to <3>, wherein the water-dispersible mineral is a layered mineral dispersed in water in a single layer state.
<5> The method for producing a three-dimensional object according to <4>, wherein the layered mineral is a synthetic hectorite.
<6> The polymerizable monomer according to any one of <3> to <5>, wherein the polymerizable monomer is at least one selected from acrylamide, N,N-dimethylacrylamide, N-isopropylacrylamide, and N-acryloylmorpholine. Is a method for manufacturing a three-dimensional molded article.
<7> In any one of <2> to <6>, including a seventh step of peeling a portion made of the hydrogel formed from the hydrogel precursor and a portion made of a polymer formed of a curable material. It is a manufacturing method of the described three-dimensional molded item.
<8> The method for producing a three-dimensional molded article according to <7>, wherein the rubber hardness of the hydrogel portion is 6 or more and 60 or less.
<9> The method for producing a three-dimensional object according to any one of <7> to <8>, in which the portion made of the hydrogel and the portion made of the polymer are separated by drying shrinkage.
<10> First means for applying a first liquid containing at least water and a hydrogel precursor to form a film,
Second means for curing the film formed in the first step,
Third means for smoothing the film cured by the second member,
An apparatus for manufacturing a three-dimensional object, comprising:
<11> First means for applying a first liquid containing at least water and a hydrogel precursor to form a film,
Fourth means for applying a second liquid containing at least a curable material to a position different from the first liquid to form a film,
Fifth means for curing the film respectively formed by the first means and the fourth means,
Sixth means for smoothing the film cured by the fifth means,
An apparatus for manufacturing a three-dimensional object, comprising:
<12> The hydrogel precursor is an apparatus for producing a three-dimensional object according to any one of <10> to <11>, which contains a water-dispersible mineral and a polymerizable monomer.
<13> The apparatus for producing a three-dimensional object according to <12>, wherein the water-dispersible mineral is a layered mineral dispersed in water in a single layer state.
<14> The layered mineral is the apparatus for producing a three-dimensional object according to <13>, which is a synthetic hectorite.
<15> The polymerizable monomer according to any one of <12> to <14>, which is at least one selected from acrylamide, N,N-dimethylacrylamide, N-isopropylacrylamide, and N-acryloylmorpholine. Is a manufacturing apparatus for a three-dimensional molded object.
<16> The means for smoothing the cured film is the apparatus for producing a three-dimensional object according to any one of <10> to <15>, which is either a roller or a blade.
<17> The device for applying a liquid to form a film is the apparatus for manufacturing a three-dimensional object according to any one of <10> to <16>, which is either an inkjet head or a dispenser.
<18> The device for curing the film is the apparatus for manufacturing a three-dimensional object according to any one of <10> to <17>, which is a member for irradiating ultraviolet light.
<19> In any one of the above <11> to <18>, which has a seventh means for separating a portion made of a hydrogel formed from the hydrogel precursor and a portion made of a polymer formed of a curable material It is a manufacturing apparatus of the described three-dimensional molded item.
<20> The apparatus for producing a three-dimensional molded article according to <19>, wherein the rubber hardness of the portion made of the hydrogel is 6 or more and 60 or less.
<21> The apparatus for producing a three-dimensional object according to any one of <19> to <20>, in which a portion made of the hydrogel and a portion made of the polymer are separated by drying and shrinking.

The method for manufacturing a three-dimensional object according to any one of the items <1> to <9> and the apparatus for manufacturing a three-dimensional object according to any one of the items <10> to <21> have the conventional problems described above. The problem is to solve it and achieve the following objectives. That is, the method for producing a three-dimensional object, and the apparatus for producing a three-dimensional object provide a method for producing a three-dimensional object and a three-dimensional object capable of easily and efficiently producing a complicated and fine three-dimensional object represented by an organ model or the like. It is an object of the present invention to provide an apparatus for manufacturing a molded article.

Japanese Patent Publication No. 2009-915143 Japanese Patent No. 4366538 Japanese Patent No. 4908679 Japanese Patent No. 3839479

DESCRIPTION OF SYMBOLS 10 Three-dimensional molded object manufacturing apparatus 11 Liquid material jetting head unit for modeling bodies 12, 13 Liquid material jetting head unit for supports 14, 15 Ultraviolet irradiation machine 16 Modeling body support substrate 17 Stage 18 Supporting body 19 Modeling bodies 20, 21, 22, 23 Smoothing member 30 Modeled body 31, 32 Support body 33 Modeled body surface (interface with support body)

Claims (7)

Water, and a first step of applying a first liquid containing at least a hydrogel precursor to form a film,
A second step of curing the film formed in the first step,
A third step of smoothing the film cured in the second step,
The method for producing a three-dimensional object is characterized in that a three-dimensional object comprising a hydrogel formed from the hydrogel precursor is produced by repeating the above step. Water, and a first step of applying a first liquid containing at least a hydrogel precursor to form a film,
A fourth step of applying a second liquid containing at least a curable material to a position different from the first liquid to form a film,
A fifth step of curing the films respectively formed in the first step and the fourth step,
A sixth step of smoothing the film cured in the fifth step,
The method for producing a three-dimensional object is characterized in that a three-dimensional object comprising a hydrogel formed from the hydrogel precursor is produced by repeating the above step. The method for producing a three-dimensional molded object according to claim 2, further comprising a seventh step of peeling off a portion formed of the hydrogel formed of the hydrogel precursor and a portion formed of a polymer formed of the curable material. The method for producing a three-dimensional molded object according to claim 3, wherein the rubber hardness of the portion made of the hydrogel is 6 or more and 60 or less. The method for producing a three-dimensional molded object according to claim 3, wherein the portion made of the hydrogel and the portion made of the polymer are peeled off by drying shrinkage. The method for producing a three-dimensional object according to any one of claims 1 to 5, wherein the hydrogel precursor contains a water-dispersible mineral and a polymerizable monomer. The method for producing a three-dimensional structure according to claim 6, wherein the water-dispersible mineral is a layered mineral dispersed in water in a single layer state.

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